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UBC Theses and Dissertations

A monograph of the genus H̲y̲g̲r̲o̲h̲y̲p̲n̲u̲m̲ Lindb.(musci) Jamieson, David William 1976

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A MONOGRAPH OF THE GENUS HYGROHYPNUM LINDB. (MUSCI) b y DAVID WILLIAM JAMIESON B... A. Humboldt State University, 1966 M.. A. Humboldt State University, 1969 A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY i n the Department of BOTANY We accept t h i s thesis as conforming to the required standard THE UNIVERSITY OF BRITISH COLUMBIA August, 1976 (c) David William Jamieson In p r e s e n t i n g t h i s t h e s i s in p a r t i a l f u l f i l m e n t o f the r e q u i r e m e n t s f o r an advanced degree at the U n i v e r s i t y o f B r i t i s h C o l u m b i a , I a g r e e that the L i b r a r y s h a l l make i t f r e e l y a v a i l a b l e f o r r e f e r e n c e and s t u d y . I f u r t h e r agree t h a t p e r m i s s i o n f o r e x t e n s i v e c o p y i n g o f t h i s t h e s i s f o r s c h o l a r l y p u r p o s e s may be g r a n t e d by the Head o f my Department o r by h i s r e p r e s e n t a t i v e s . It i s u n d e r s t o o d tha t c o p y i n g o r p u b l i c a t i o n o f t h i s t h e s i s f o r f i n a n c i a l g a i n s h a l l not be a l l o w e d w i t h o u t my w r i t t e n p e r m i s s i o n . Department o f ]?oT^2/rtt^  The U n i v e r s i t y o f B r i t i s h C o l u m b i a 2075 Wesbrook Place Vancouver, Canada V6T 1W5 Date 12 XL \CJX1L Chairman: Professor W. B. S c h o f i e l d ABSTRACT The genus Hygrohypnum Lindb. (Musci) i s monographed f o r the world f o r the f i r s t time. T h i r t y - n i n e species and a large number of s u b s p e c i f i c taxa recognised at the inception of t h i s study were in v e s t i g a t e d using t r a d i t i o n a l t ools of herbarium taxonomy, extensive f i e l d work throughout North America and the experimental c u l t i v a t i o n of ten North American species i n a uniform environment. These studies show that Hygrohypnum i s a Northern Hemisphere genus, i n which the important taxonomic characters are: stem anatomy, shape of the l e a f and i t s apex, l e a f concavity, costa s t r u c t u r e , a l a r c e l l d i f f e r -e n t i a t i o n , length of the marginal l e a f c e l l s , s e x u a l i t y , s tructure of the p e r i c h a e t i a l leaves and the annulus. Based on these characters the f o l -lowing 16 species are recognised: H_. alpinum (Lindb.) Loesk. , H_. durius- culum (De Not.) nov. comb., H. s m i t h i i (Sw. i n L i l j . ) Broth., _. b e s t i i (Ren. et Card.) Holz. , H_. c o c h l e a r i folium (Vent, i n De Not.) Broth., H. norvegicum (Schimp.) Amann, H_. mo l i e (Hedw.) Loesk., H. styriacum (Limpr.) Broth., H. luriduirt (Hedw.) Jenn. , H. a l p e s t r e (Hedw.) Loesk., H. polare (Lindb.) Loesk., _. ochraceum (Wils. ex Turn.) Loesk., H. eugyrium (Schmip.) Broth., H_. subeugyrium (Ren. et Card.) Grout, H. montanum (Lindb.) Broth., and H. c l o s t e r i (Aust.) Grout. Hygrohypnum  alpinum and H_. styriacum are new i n Western North America and H_. b e s t i i , known previously as a Western North American endemic, i s now shown to be on the Upper Peninsula of Michigan and around the Gulf of St. Lawrence. The taxonomic treatment presents a generic d e s c r i p t i o n and keys to the species and provides each species with a d e s c r i p t i o n , a discussion of i i i v a r i a b i l i t y and taxonomic matters, i l l u s t r a t i o n s and a d i s t r i b u t i o n map. The status of each ..excluded taxon i s discussed. The generic concept and the possible r e l a t i o n s h i p s among the recog-nised species are examined by comparing the author's opinion with i n f o r -mation derived from an ordination and two c l u s t e r analyses. TABLE OF CONTENTS ABSTRACT LIST OF FIGURES LIST OF TABLES ACKNOWLE DGMENTS INTRODUCTION THE TAXONOMIC HISTORY OF THE GENUS METHODS OF THE MORPHOLOGICAL ANALYSIS METHODS OF CULTIVATION METHODS OF PREPARATION OF MATERIAL FOR MICROSCOPE EXAMINATION RESULTS OF THE MORPHOLOGICAL ANALYSIS Stem Anatomy-Leaf Shape and Symmetry Leaf Apex Costa Leaf Concavity Median Leaf C e l l s A l a r C e l l s Response to Drying Sexuality P e r i c h a e t i a l Leaves Sporophyte TAXONOMIC TREATMENT Generic Synonomy Generic Description of Hygrohypnum Key to the Species of Hygrohypnum V Hygrohypnum alpinum 98 Hygrohypnum duriusculum 113 Hygrohypnum s m i t h i i 136 Hygrohypnum b e s t i i 150 Hygrohypnum cochleari folium ...169 Hygrohypnum norvegicum 184 Hygrohypnum molle 193 Hygrohypnum styriacum 211 Hygrohypnum luridum 224 Hygrohypnum alpestre 270 Hygrohypnum polare 282 Hygrohypnum ochraceum 299 Hygrohypnum eugyrium 329 Hygrohypnum subeugyrium 347 Hygrohypnum montanum 36 3 Hygrohypnum c l o s t e r i 375 EXCLUDED SPECIES AND SPECIES OF QUESTIONABLE AFFINITIES 387 DISCUSSION 398 LITERATURE CITED 418 v i LIST OF FIGURES FIG. 1 V a r i a t i o n i n stem anatomy 23 FIG. 2 Terminology of le a f shape 28 FIG. 3 Comparison of l e a f shape v a r i a t i o n within and between species 30 FIG. 4 Comparison of l e a f shape v a r i a t i o n within and between species 32 FIG. 5 Comparison of l e a f shape v a r i a t i o n within and ~ between species 34 FIG. 6 Comparison of l e a f shape v a r i a i t o n within and between species 36 FIG. 7 Comparison of l e a f shape n a t u r a l l y growing plants and t h e i r response to a r t i f i c i a l culture 38 FIG. 8 Comparison of l e a f shape i n n a t u r a l l y growing plants and t h e i r response to a r t i f i c i a l culture 40 FIG. 9 Comparison of l e a f shape i n n a t u r a l l y growing plants and t h e i r response to a r t i f i c i a l culture 42 FIG. 10 Descriptive terminology f o r the shape of the l e a f apex 46 FIG. 11 V a r i a t i o n i n the shape of the l e a f apex 48 FIG. 12 V a r i a t i o n i n the shape of the l e a f apex 50 FIG. 13 The nature of l e a f concavity 54 FIG. 14 V a r i a t i o n i n marginal l e a f c e l l s 57 FIG. 15 V a r i a t i o n i n marginal l e a f c e l l s 59 FIG. 16 V a r i a t i o n i n a l a r c e l l d i f f e r e n t i a t i o n 64 FIG. 17 V a r i a t i o n i n a l a r c e l l d i f f e r e n t i a t i o n 66 FIG. 18 V a r i a t i o n i n a l a r c e l l d i f f e r e n t i a t i o n 68 FIG. 19 V a r i a t i o n i n a l a r c e l l d i f f e r e n t i a t i o n 70 FIG. 20 V a r i a t i o n i n the a l t e r a t i o n i n habit from wet to dry conditions i n morphologically d i f f e r e n t shoots 74 VI1 FIG. 21 Variation i n alteration in habit from wet to dry conditions in morphologically different shoots 76 FIG. 22 The pseudo-paroicous inflorescence of Hygrohypnum styriacum 79 FIG. 23 Variation i n the perichaetial leaf apex 83 FIG. 24 Variation in the perichaetial leaves 85 FIG. 25 Variation i n the perichaetial leaves 87 FIG. 26 Variation i n the leaf shape and the habit of the shoots of Hygrohypnum alpinum 107 FIG. 27 Cellular detail of the perichaetial and foliage leaves of Hygrohypnum alpinum 109 FIG. 28 Distribution.map of Hygrohypnum alpinum 110 FIG. 29 Variation i'n_the habit of leaf shoots of Hygrohypnum duriusculum and comparisons . between the wet and dry conditions in the shoots of Hygrohypnum duriusculum 124 FIG. 30 Variation i n the leaf shape, length of marginal leaf cells and the habit of leafy shoots of Hygrohypnum duriusculum 126 FIG. 31 Variation i n the apices and the cellular detail of the leaves of Hygrohypnum duriusculum 128 FIG. 32 Distribution map of Hygrohypnum duriusculum 129 FIG. 33 Variation in the leaf shape and the habit of leafy shoots of Hygrohypnum smithii 143 FIG. 34 Cellular details of the perichaetial and foliage leaves of Hygrohypnum smithii 145 FIG. 35 Distribution map of Hygrohypnum smithii 146 FIG. 36 Variation in the habit of the .shoots of. ,J Hygrohypnum besti i and a comparison of individual shoots i n the wet and dry conditions 159 FIG. 37 Variation in the leaf shape of Hygrohypnum bestii 161 FIG. 38 Cellular detail of the foliage leaves, of Hygrohypnum besti i 16 3 FIG. 39 Distribution map of Hygrohypnum be s t i i 164 v i i i FIG. 40 V a r i a t i o n i n the l e a f shape and the habit of the moist shoots of Hygrohypnum cochlearifolium 178 FIG. 41 C e l l u l a r d e t a i l of the leaves of Hygrohypnum cochlearifolium 180 FIG. 42 D i s t r i b u t i o n map of Hygrohypnum cochlearifolium 181 FIG. 43 V a r i a t i o n i n the l e a f shape, the c e l l u l a r d e t a i l of the f o l i a g e leaves and the habit of the shoots of Hygrohypnum norvegicum 190 FIG. 44 D i s t r i b u t i o n map of Hygrohypnum norvegicum 191 FIG. 45 V a r i a t i o n i n the le a f shape and the habit of the shoots of Hygrohypnum molie 204 FIG. 46 C e l l u l a r d e t a i l of the f o l i a g e and p e r i c h a e t i a l leaves of Hygrohypnum molie 206 FIG. 47 D i s t r i b u t i o n map of Hygrohypnum molie 207 FIG. 48 V a r i a t i o n i n l e a f shape and shoot habit of Hygrohypnum styriacum 218 FIG. 49 C e l l u l a r d e t a i l of the f o l i a g e leaves of Hygrohypnum styriacum 220 FIG. 50 D i s t r i b u t i o n map of Hygrohypnum styriacum 221 FIG. 51 V a r i a t i o n i n the habit of the moist shoots of Hygrohypnum luridum 249 FIG. 52 V a r i a t i o n i n the le a f shape of Hygrohypnum luridum 251 FIG. 53 V a r i a t i o n i n the l e a f shape of Hygrohypnum luridum 253 FIG. 54 V a r i a t i o n i n the c e l l u l a r d e t a i l of the fo l i a g e leaves of Hygrohypnum luridum 255 FIG. 55 V a r i a t i o n i n a l a r c e l l d i f f e r e n t i a t i o n of Hygrohypnum luridum 257 FIG. 56 D i s t r i b u t i o n map of Hygrohypnum luridum, 258 FIG. 57 V a r i a t i o n i n the l e a f shape and the habit of the shoot of Hygrohypnum alpestre 2 76 FIG. 58 C e l l u l a r d e t a i l of the f o l i a g e leaves of Hygrohypnum alpestre 278 FIG. 59 D i s t r i b u t i o n map of Hygrohypnum alpestre 279 X X FIG. 60 V a r i a t i o n i n the l e a f shape and the habit of the shoots of Hygrohypnum polare 292 FIG. 61 C e l l u l a r d e t a i l s of the f o l i a g e leaves and the stem of Hygrohypnum polare 294 FIG. 62 D i s t r i b u t i o n map of Hygrohypnum polare 295 FIG. 63 Variation:'-in the habit of l e a f y shots of Hygrohypnum ochraceum and comparisons between the wet and dry conditions i n the shoots 313 FIG. 64 V a r i a t i o n i n the le a f shape of Hygrohypnum ochraceum 315 FIG. 65 C e l l u l a r d e t a i l of the f o l i a g e leaves of Hygrohypnum ochraceum 317 FIG. 66 The stem anatomy and the v a r i a t i o n i n the a l a r c e l l s of Hygrohypnum ochraceum 319 FIG. 67 D i s t r i b u t i o n map of Hygrohypnum ochraceum 320 FIG. 68 V a r i a t i o n i n the habit of the shoot and the l e a f shape of Hygrohypnum eugyrium 339 FIG. 69 C e l l u l a r d e t a i l of the leaves and the stem of Hygrohypnum eugyrium 341 FIG. 70 D i s t r i b u t i o n map of Hygrohypnum eugyrium 342 FIG. 71 V a r i a t i o n i n the l e a f shape and the habit of the shoot of Hygrohypnum subeugyrium i n Europe and North America 357 FIG. 72 V a r i a t i o n i n the le a f shape and the habit of the shoot of Hygrohypnum subeugyrium i n Japan 359 FIG. 73 C e l l u l a r d e t a i l of the f o l i a g e leaves of Hygrohypnum subeugyrium 361 FIG. 74 D i s t r i b u t i o n map of Hygrohypnum subeugyrium 362 FIG. 75 The habit of,the shoot and v a r i a t i o n i n l e a f shape of Hygrohypnum montanum 370 FIG. 76 C e l l u l a r d e t a i l of the f o l i a g e leaves of Hygrohypnum montanum 372 FIG. 77 D i s t r i b u t i o n map of Hygrohypnum montanum 373 X FIG. 78 The habit of the shoot and the v a r i a t i o n i n , le a f shape of Hygrohypnum c l o s t e r i 382 FIG. 79 C e l l u l a r d e t a i l of the f o l i a g e leaves of Hygrohypnum c l o s t e r i 384 FIG. 80 D i s t r i b u t i o n map of Hygrohypnum c l o s t e r i 385 FIG. 81 Possible r e l a t i o n s h i p s among the species of Hygrohypnum 400 FIG. 82 Weighted p a i r group c l u s t e r analysis 411 FIG. 83 Unweighted p a i r group c l u s t e r analysis 412 FIG. 84 Ordination analysis of Hygrohypnum 413 x i LIST OF TABLES TABLE 1 Morphological features subject to analysis 18 TABLE 2 A comparison of the species of Hygrohypnum and the taxonomically important features within the genus 406-418 TABLE 3 S i m i l a r i t y matrix 410 x i i ACKNOWLEDGMENTS I would l i k e to express sincere thanks to Dr. W i l f r e d B. S c h o f i e l d for h i s friendship and h i s patient support and encourage-ment throughout t h i s study. Thanks...are also due the National Research Council of Canada f o r f i n a n c i a l support through grant A1217 to Dr. S c h o f i e l d and the University of B r i t i s h Columbia Research Committee. The cooperation of the curators of the following herbaria i s g r a t e f u l l y acknowledged (abbreviations according to Holmgren and Kueken, 1974) : ALTA, B, BM, BP, BRNM, C, CAL, CANM, COLO, DUKE, F, FB, FH, FLAS, G, GRO, H, H-BR, H-SOL, HSC, JE, KRAK, LD, LE, MAK, MICH, MIN, MO, MNA, NFLD.', ... NICH, NSPM, NY, 2NYS, OTT, P, S-PA, TENN, TRTC, UAC, UBC, UC, US, UWO, WTU. My .thanks are also extended to Dr. W. D. Margadant of Utrecht f o r advice on nomenclatural matters. For much of the success i n my f i e l d work, I am most g r a t e f u l to Dr. F. J . Hermann of Fort C o l l i n s , Colorado, as the extremely accurate c o l l e c t i n g data on his widely d i s t r i -buted specimens allowed me to relocate many c r u c i a l species. I,..would l i k e to thank my committee for t h e i r p atient e f f o r t s i n reading the thesis and t h e i r constructive c r i t i c i s m of i t . I would also l i k e to o f f e r a most sincere thank you to Drs. Jack R. Maze and Janet R. Stein. Many unorthodox and provocative discussions with Dr. Maze allowed me r e i n f o r c e many of my ideas while f o r c i n g me to rethink others. Dr. S t e i n graciously typed the corrections during the proofing of the f i n a l manuscript and was a much appreciated source of encouragement during the f i n a l months of work. L a s t l y , I acknowledge the encouragement I have received from the many friends I have made during my long tenure at The University of B r i t i s h Columbia. 1 INTRODUCTION Hygrohypnum i s a genus of semi-aquatic pleurocarpous mosses that i s c u r r e n t l y treated i n the family Amblystegiaceae, i t s e l f a group of taxa of predominantly aquatic or otherwise damp environments. Certain taxa presently treated within the genus can be traced to Hedwig's (1801) Species Muscorum, but the o r i g i n a l concept of the genus dates from Schimper (1853) i n Bryologia Europaea. Schimper named the genus Limnobium Schimp. and distinguished i t from Hypnum on the basis of the bdtoadly ovate-lanceolate to almost o r b i c u l a r leaves and the nature of the a l a r c e l l s which were sa i d to be hardly d i f f e r e n t i a t e d from other basal l e a f c e l l s and l i t t l e or not at a l l i n f l a t e d or excavated. Of the habitat i n which the genus grew, Schimper noted only that the name, Limnobium, r e f l e c t e d the habitat of the f i v e o r i g i n a l species. The manifold systematic problems i n the genus Hygrohypnum have t h e i r o r i g i n i n the habitat i n which £he genus occurs and the absence of a sound, modern generic concept. Hygrohypnum normally occurs on rocks or stones between the high and low water l e v e l s ; or, i n or beside small, cold, s w i f t l y running mountain streams. Like other plants of s i m i l a r environments various r e a l and alleged species of Hygrohypnum have responded to the f l u c t u a t i n g water l e v e l s by assuming a myriad of forms which have blurred species l i m i t s . I t i s to be expected then, that the species concepts held by many workers have been badly confused and that among the most v a r i a b l e species numerous: subsp e c i f i c taxa have been recognized. Renauld (1883) revised the European species and presented a more precise generic circumscription and Brotherus (1909 and 1925) provided keys to the species or c e r t a i n groups of species known to those times. The genus has been 2 treated i n numerous regional f l o r a s (Braithwaite, 1898; Limpricht 1904; Roth, 1905; Dixon, 1896 and 1924; Brotherus, 1923? Monkemeyer, 1927; Grout, 1931; Nyholm, 1965 and others), but i t has never been revised on a world wide basi s . As a r e s u l t of t h i s neglect many taxa have been des-cribed under d i f f e r e n t names, while others of diverse and questionable a f f i n i t i e s have been included within the genus, apparently for the sole reason that the plants occured on rocks i n streams. This generic hetero-geneity prompted Loeske (1910) to r e f e r to Hygrohypnum as a "biologische Mischgattung." The objectives of t h i s monograph have been to: 1. assess a l l of the described species to circumscribe a more natural genus, 2. discern stable morphological characters with which to d i s t i n g u i s h species, 3. provide keys to and de s c r i p t i o n s , i l l u s t r a t i o n s and maps of a l l the recognized species and 4. put into usuable d e s c r i p t i v e form an assessment of the v a r i a t i o n that may be encountered i n each species. To accomplish these goals Hygrohypnum has been investigated i n three ways. l : F i e l d work was conducted throughout North America i n order to assess the e c o l o g i c a l amplitude of the genus and to gain f i e l d experience to assess natural v a r i a b i l i t y i n the recognized taxa. 2. Ten species from diverse l o c a l i t i e s from throughout North America were grown under uniform environment to determine the s t a b i l i t y o f c e r t a i n morphological characters. 3. More than 2,200 herbarium speciments were dissected and made int o microscope s l i d e preparations f o r c r i t i c a l study. Subsequently more than 13,000 specimens were examined and annotated. 2a . ' Many D a r w i n i a n s y s t e m a t i s t s h a v e e x p r e s s e d t h e v i e w t h a t a c l a s s i - ' f i c a t i o n s y s t e m s h o u l d r e f l e c t p h y l o g e n y . T h i s i s a v e r y d e s i r a b l e g o a l , b u t u n f o r t u n a t e l y an u n d e r s t a n d i n g o f p h y l o g e n y depends on t h e e x i s t e n c e o f a f o s s i l r e c o r d , w h i c h a l l t oo o f t e n i s f r a g m e n t a r y a t b e s t . I n t h e a b s e n c e o f a f o s s i l r e c o r d t h e r e l a t i o n s h i p s among e x -t a n t s p e c i e s may be i n f e r r e d o r o c c a s i o n a l l y e s t a b l i s h e d f r o m d a t a on k a r y o l o g y , b r e e d i n g s y s t e m s , d e v e l o p m e n t , c h e m i s t r y , e c o l o g y and p h y t o g e o g r a p h y . H o w e v e r , when t h e o n l y a v a i l a b l e d a t a a r e d e r i v e d f r o m e x t e r n a l , a d u l t m o r p h o l o g y i t i s v e r y d i f f i c u l t , i f n o t i m p o s s i b l e t o t r u l y u n d e r s t a n d t h e b i o l o g i c a l r e l a t i o n s s h i p s among a g roup o f s p e c i e s . As a c o n s e q u e n c e I h a v e n o t s p e c u l a t e d on t h e p h y l o g e n y o f Hygrohypnum. The s e q u e n c e i n w h i c h t he s p e c i e s o f Hygrohypnum a r e p r e s e n t e d i n t h i s wo rk r e p r e s e n t s a s e r i e s o f o v e r l a p p i n g p a t t e r n s o f m o r p h o l o g i c a l v a r i a t i o n . The d e s i g n o f t h i s s e q u e n c e s e r v e s o n l y t o e l u c i d a t e t r e n d s i n a d u l t m o r p h o l o g y . The s e q u e n c e o f s p e c i e s i s g r a p h i c a l l y r e p r e s e n t e d i n f i g . 81 on page 4 0 0 . The most i m p o r t a n t m o r p h o l o g i c a l t r e n d s a r e as f o l l o w s ; 1 . L e a v e s v e r y b r o a d t o n a r r o w . 2 . L e a v e s e x c l u s i v e l y s t r a i g h t t o s t r a i g h t a n d / o r f a l c a t e . 3 . A l a r c e l l s m o s t l y u n d i f f e r e n t i a t e d t o v a r i o u s l y d i f f e r e n t i a t e d . 4 . S tem anatomy e x h i b i t i n g a c o r t e x o f s m a l l , t h i e k - w a l l e d ~ c e l l s , a m e d u l l a o f l a r g e r , t h i n n e r - w a l l e d c e l l s and a c e n t r a l s t r a n d t o a more v a r i a b l e p a t t e r n ..of d i f f e r e n t i a t i o n . 5 . P l a n t s m o s t l y a u t o i c o u s t o p l a n t s w i t h a more v a r i a b l e s e x u a l i t y . 3 THE TAXONOMIC HISTORY OF HYGROHYPNUM Progress i n the study of mosses has been dependent upon technical advances i n microscopy. The i n a b i l i t y to observe microscopic features caused e a r l y workers to employ very broad generic concepts. As a con-sequence, pleurocarpous mosses, exclusive of F o n t i n a l i s , were o r i g i n a l l y treated i n the a l l i n c l u s i v e genus Hypnum. Hedwig (1801) was the f i r s t to use microscopic features i n c l a s s i f y i n g mosses and with h i s work com-menced the gradual subdivision of the genus Hypnum sensu l a t u i n t o many smaller, more natural genera. In the following discussion the taxonomic h i s t o r y of Hygrohypnum i s traced to three Hedwigian species and i s then followed through the des-c r i p t i o n of a d d i t i o n a l species and t h e i r subsequent treatment i n various s e c t i o n a l and subgeneric groupings of Hypnum or i n such segregate genera as Limnobium, Stereodon, Amblystegium, C a l l i e r g o n and ul t i m a t e l y Hygro- hypnum . In the following discussion i t should be understood that the c l a s s i f i c a t i o n s ascribed to each c i t e d author have been edited ao as to deal only with those taxa that are considered to be modern species of Hygrohypnum or a synonym * thereof. The o r i g i n s of the genus can be traced to three species treated by Hedwig within the broadly conceived genus Hypnum Hedw. In h i s Species  Muscorum Hedwig (1801) subdivided Hypnum into eight numbered groups to which he gave neither formal nor h i e r a r c h i c a l ranking. As c r i t e r i a for d e l i m i t i n g h i s eight groups Hedwig emphasized l e a f symmetry and the various attitudes the leaves exhibited along the stems. Branching patterns were also used, but were subordinate to l e a f characters. By modern standards, the taxa included i n these e a r l y groupings are of diverse r e l a t i o n s h i p s . However, i n terms of the characters used, Hedwig's groups were reasonably 4 sound, Hedwig:1 (recognized and c l a s s i f i e d Hypnum alpestre, H. molle and H. luridum as follows: Group I I I , F o l i i s r e c t i s , a e qualiter et arete i m b r i c a t i s , (ramis t e r e t i b u s ) . Hypnum alpestre Sw. ex Hedw. Group IV, F o l i i s r e c t i s , a e qualiter e t laxe incumbentibus, ramis p i n n a t i s . Hypnum molle Dicks. Hedw. Group VIII, F o l i i s secundis, i n c u r v i s . Hypnum luridum Hedw. B r i d e l (1801) recognized Hypnum palustre Huds, ex Br i d . , and H. molle Dicks., but d i d not t r e a t H, alpestre Sw. Like Hedwig, B r i d e l subdivided Hypnum in t o eiijht groups, but he applied to them formal names apparently of sec t i o n a l rank. In d i r e c t contrast to Hedwig, B r i d e l placed greater weight on branching pattern i n d e l i m i t i n g h i s groups and relegated l e a f form and o r i e n t a t i o n upon the stems to subordinate r o l e s . B r i d e l ' s c l a s s i f i c a t i o n of Currently recognized species of Hygrohypnum i s as follows: Group V, section Scuiroidea, Surculo confertim ramoso. subgroup 2, f o l i i s secundis r e f l e x i s contorsive. Hypnum palustre Huds. ex Br i d , Group VIII, section Polymorpha, Surculo vage ramoso„ f o l i i s d i r e c t i o n ^ ; aequali. subgroup 4, Amphibia Hypnum molle, Dicks. B r i d e l (1812) modified h i s e a r l i e r c l a s s i f i c a t i o n system along the l i n e s of Hedwig's and subdivided Hypnum into nine groups. Ihese groups and a number of t h e i r subdivisions were given formal names at se c t i o n a l rank. Through a typographical error the number 2 was used twice i n denoting the groups and consequently the nine groups nufabered only eight. In the new system B r i d e l placed greater value on l e a f characters and relegated branch-5 ing features to a l e s s e r r o l e . B r i d e l ' s c l a s s i f i c a t i o n as applied to Hygrohypnum i s given below: 1 Group 2 Section I l l e c e b r a , f o l i i s i m b r i c a t i s appressa v e l appresso patentiusculus, ramis p i n n a t i s v e l subpinnatis, ramulis teretibus obtusis. Hypnum alpestre Sw. and Hypnum molle Dicks. Section Cuspidata, f o l i i s i m b r i c a t i s appressa v e l appresso patentiusculus, ramis p i n n a t i s v e l subpinnato, ramulis compressisculus a c u t i s . Hypnum negleetum B r i d . Group 7, f o l i i s secundis c i r c i n n a t o - f a l c a t i s Section Lurida, caulibus con€ertim ramosus. Hypnum luridum Hedw. and Hypnum subsphaericarpon B r i d . I t seems apparent here that B r i d e l recognized the s i m i l a r i t i e s of Hedwig*s treatment of Hypnum alpestre Sw. and Hedwig's and h i s own tr e a t ment of Hypnum molle f o r he included them both i n section I l l e c e b r a . The c l a s s i f i c a t i o n presented by B r i d e l (1827) was e s s e n t i a l l y unchanged from the system of 1812. He did correc t the erro r i n the group numberings and he excluded Hypnum negleetum B r i d . The most s i g n i f i c a n t change occurced i n the d i v i s i o n of Hypnum into two subgenera based on endostomial characters. Subgenus Hypnum, peristome i n t e r i o r i s c i l i i s p e r f o r a t i s . Subgenus Stereodon, peristome i n t e r i o r i s c i l i i s imperforatis. Hypnum molle, H. alpestre, H. p a l u s t r i s and H. subsphaericarpon were a l l included i n the subgenus Stereodon. 1 Indicates the second and erroneously numbered group 2 6 Sprengel (1827) subdivided Hypnum into three groups, each of which was subdivided into a number of smaller groups. Like Hedwig and B r i d e l , Sprengel used l e a f symmetry and l e a f a t t i t u d e upon the stem as characters of primary importance. However, he appears to have been the f i r s t to employ costa structure, smoothness or p a p i l l o s i t y of the l e a f c e l l s and toothing of the l e a f margin as c l a s s i f a c t o r y c r i t e r i a . Using these features, Sprengel divided Hypnum into three numbered groups of unspecified rank. Group 2, F o l i i s secundis, * n e r v o f f i s . Hypnum spfaaericarpon Spreng. ** F o l i i s secundis enervis. Hypnum palustre (no authority designated) Group 3, F o l i i s d i r e c t i o n e varius * F o l i i s d i r e c t i o n e v a r i i s e r e c t o - p a l u l i s , Nervo evanido, F o l i i s integerrimus, F o l i i s fetisque laevibus. Hypnum molle Dicks, and Hypnum neglectum B r i d . Hypnum sphaericarpon was an obvious m i s s p e l l i n g of Hypnum subsphaeri- carpon B r i d . I t i s worth noting that where B r i d e l recognized s u f f i c i e n t s i m i l a r i t y between Hypnum molle Dicks, and H. alpestre Sw. to include them within the same grouping, Sprengel united the two under H. molle Dicks. Hiibner ^1833) divided Hypnum into several sections, f o r which he provided elaborate d e s c r i p t i o n s . His treatment i s unique f o r within section A l p e s t r i a he included only taxa that have since been included within Hygro- hypnum . His treatment i s as follows: Section A l p e s t r i a Caule f a s c i c u l a t i m ramoso, ramis c o n f e r t i s e r e c t i s simplicibus turgido-teretibus, f o l i i s dense imbricatis basinervibus, s e t i s laevibus. Hypnum molle Dicks. Hypnum alpestre Sw., Hypnum palustre Linn. Hypnum sphaericarpon Spreng. Hampe (1837) divided Hypnum into two apparent subgenera which he c a l l e d Isothecium B r i d , and Stereodon et Hypnum Br i d . These two groups were subdivided further, but Hampe d i d not indic a t e the c r i t e r i a he used. His treatment i s unique f o r he treated Hypnum luridum Hedw. and H. sphaeri- carpon B r i d . as v a r i e t i e s of Hypnum palustre Linn, and placed Hypnum alpestre Sw, as a v a r i e t y of molle Dicks. De Notaris (1838) provided a treatment s i m i l a r to that of Hiibner, In hi s Hypnum sect. P a l u s t r i a De Notaris c l e a r l y included taxa that have a l l become recognized species of Hygrohypnum or synonyms of recognized species, De,Notaris" system i s given below: Hypnum sect. P a l u s t r i a De Not. Caule repentes confertim ramosi, f o l i a imbricata plerumque secunda, subfalcative concaviscula, tenuieve seta l a e v i . Hypnum palustre B r i d . Hypnum subsphaericarpon B r i d . Hypnum molle Dicks. Schimper (1853, i n Bruch, Schimper and Gumbel) presented the f i r s t con-ceptual synthesis of the modern genus Hygrohypnum. Schimper extracted Hypnum  luridum Hedw,, H. molle Hedw, and H_. alpestre Hedw. from Hypnum and placed them i n the new genus Limnobium Schimp. Hypnum subsphaericarpon B r i d . and H. negleetum B r i d . were shown to be variants of H. luridum Hedw. and united 8 with i t . Simultaneously, he described Limnobium norvegicum Schimp. and L. arcticum Schimp. Schimper (1855) added Limnobium eugyrium Schimp, and L. ochraceum (Turn, ex Wils.) Schimp. In so doing, Schimper brought to -gether a group of species e x h i b i t i n g such a d i v e r s i t y of form as to have widely spaced to crowded branches, s t r a i g h t , l o o s l y appressed to spreading or falcate-secund leaves, pointed or obtuse branch t i p s and short and double or s i n g l e costae. However, Schimper determined that these taxa shared a s i m i l a r a r e o l a t i o n , a Seldom excavated region of poorly defined a l a r c e l l s , a broadly ovate-lanceolate or o r b i c u l a r l e a f shape and a common habit a t i n and around streams. Wilson (1855) retained a more conservative view and treated present day species of Hygrohypnum as Hypnum. He divided Hypnum into three groups based upon l e a f symmetry and l e a f a t t i t u d e upon the stem. He treated various species of Hypnum as follows: Section I, leaves + spreading i n everyway. Section A l p e s t r i a A. Stems creeping, i r r e g u l a r l y branched; or o c c a s i o n a l l y arched pinnate, *** Leaves roundish, rather obtuse, e n t i r e , two nerved, nerveless. Hypnum molle Dicks. Hypnum palustre D i l l . , Linn. Hypnum arcticum Sommerf. SSction I I , leaves secund. Section Cuppressiformia B. Stem procumbent, + e n t i r e , f r u c t i f i c a t i o n s near the base; leave falcate-secund, e n t i r e or s e r r u l a t e , nerveless or two nerved at the base, * Leaves acpuminate. 9 Hypnum ochraceum Turn. Commencing with S u l l i v a n t (1856) the genus Limnobium Schimp. was subjected to a v a r i e t y of i n t e r p r e t a t i o n s . S u l l i v a n t (1856) and Schimper (1860 and 1876) interpreted the taxon as a subgenus of Hypnum. Renauld (1883), Boulay (1884), Husnot (1894) and Dixon (1896 and 1924) treated Limnobium as a section of Hypnum. Mitten (1864) d i f f e r e d s l i g h t l y t r e a t -ing Section Limnobium within Stereodon B r i d . Renauld (1883) c r i t i c a l l y revised the European species as Hypnum section Limnobium. In so doing he of f e r e d some s i g n i f i c a n t i n s i g h t into the s e c t i o n . He observed that the section could be subdivided into two groups based on l e a f morphology. He characterized the groups as follows: Group 1, Les f e u i l l e s sont e l a r g i e s ovales ou suborBiculaire, souvent contractees k l a base, arrondes ou sommet ou brieviment et obtusement apiculees. Hypnum dilatatum Wis. Hypnum molle Dicks. Hypnum alpinum Sch. 5* arcticum Sommerf, H. g o u l a r d i i Sch. H. obtusifolium Hook. Group 2, Les f e u i l l e s sont oblongues ou oblongues-lanceolees, plus ou moms retrecies-acummees. Hypnum palustre L. H. polare Lindb, H, alpestre Sw. H. eugyrium B.S.G. H. lusitanicum Sch. 10 H. micans Wils. H. ochraceum Turn. De Bat (1885) presented a r e c l a s s i f i c a t i o n of the genus Hypnum within which modern species of Hygrohypnum were treated i n two sections. His systems para l l e l e d that of Renauld (1883) emphasizing groups of species exhibiting straight, orbicular leaves which he c a l l e d section Eu-Limnobium and those species bearing straight or falcate, more or less lanceolate leaves, which he placed i n section Hetero-Limnobium. De Bat's system i s as follows: Eu-Hypnum a. R e c t i f o l i a re 1 Section, a ramification i r r e g u l i e r e (correspond aux simplicia) SECTION Eu-LiMhobia A. F e u i l l e s c i r c u l a i r e s ou ovales-circulaires ou avec obtus (corres-pondent aux o b t u s i f o l i a ) H. alpinum H. go u l a r d i i H. alpestre H. dilatatum H. molle H. norvegicum H. deflexifolium (= Scorpiurium) B. F e u i l l e s ovales-acuminees peu ou appeine homotropes H. lusitanicum H. polare H. micans 11 B. C u r v i f o l i a - F e u i l l e s ovales-oblongues ou ovales lanceolees, nettement homotropes ou incurvees. SECTION Hetero-Limnobia H. ochraceum H. subenerve H. eugyrium H. palustre L i n d b e r g h 187 2) observed that Limnobium Schimp, was a l a t e r homonym of Limnobium Rich., a genus of the Hydrocharitaceae. As a substitute f o r Limnobium Schimp, Lindberg coined the name Hygrohypnum Lindb. Later, Lindberg (1879) reduced Hygrohypnum Lindb. to subgeneric status under Amblystegium Schimp, Braithwaite (1898) treated Hygroftfrpnum Lindb. as a section of Amblystegium and Limpricht (1904) placed Hygrohypnum Lindb. as subgenus i n Hypnum. Kindberg (1894) continued to use Limnobium f o r c e r t a i n c u r r e n t l y recognized species of Hygrohypnum and at the same time elevated Hypnum subg. C a l l i e r g o n S u l l . to genus. In C a l l i e r g o n Kindberg treated species now r e f e r r e d to C a l l i e r g o n and Hygrohypnum. Kindberg (1897) elaborated h i s concept of C a l l i e r g o n and described a number of subgenera and sections which included species of modern C a l l i e r g o n , Drepanocladus, Scorpidium, Sematophyllum and Hygrohypnum. Modern species of Hygrohypnum were d i s -t r i b u t e d i n Kindberg's treatment^of C a l l i e r g o n as follows: C a l l i e r g o n subg. Limnobium A. Capsule not annulate, Leaves e n t i r e , I I . Leaves of stem not f a l c a t e , those of the branches f a l c a t e , a l a r ^ c e l l s not large, costa abreviate sometimes double or i n d i s t i n c t . Pedicel of capsule s h o r t i s h . Stems creeping or pinnate. 12 C a l l i e r g o n palustre (L.) Kindb. C a l l i e r g o n subg. Pseudo-Limnobium Kindb. B. ..Capsule annulate, Leaves sometimes denticulate, b. stems not pinnate, sometimes radiculose, a l a r c e l l s generally d i s t i n c t . Section Badiiformia Kindb. Leaves not decurrent, those of branches often f a l c a t e . Dioicous and very r . f r u i t i n g . rCalliergon"polare -(Lindb.)' Kindb. Section Ochraceiformra Kindb. bb. Costa generally short and i n d i s t i n c t , 2 . Leaves i .....entire or nearly so, decurrent and d i s t a n t , those of branches often f a l c a t e , stems eradiculose, dioicous r a r e l y f r u i t i n g . C a l l i e r g o n ochraceum (Turn, ex Wils.) Kindb. C.- t o r r e n t i s Kindb. C. g o u l a r d i i (Schimp.) Kindb. Section M o l l i f o r m i a Kindb. bb. Costa generally short and i n d i s t i n c t , 3...Leaves not or i n d i s t i n c t l y decurrent, sometimes denticulate, generally crowded and not f a l c a t e , Stem not creeping vs. radiculose. Often monoicous. C a l l i e r g o n eugyrium (B.S.G.)"Kindb. C_. arcticum (Sommerf.) Kindb. C_. molle (Dicks.) Kindb. C_. alpestre (Sw.) Kindb. C. columbico-palustre CM. §_t Kindb. 13 C_. c i r c u l i f o l i u m CM. ert, Kindb. C. submolle Kindb. Section Montaniforme Kindb. Leaves small, sometimes decurrent, usually denticulate, those of the branches often f a l c a t e . Stems creeping vs. monoecious. C a l l i e r g o n pseudo-arcticum Kindb. C_. montanum (Lindb.) Kindb. C_. pseudo-montanum Kindb. C. viridulum (Hartm.) Kindb. Paris (1905) and Roth (1905) used Limnobium Schimp. i n t h e i r p u b l i -cations.- Loeske (1903) recognized^: the p r i o r i t y of Hygrohypnum Lindb., but i t was not u n t i l Brotherus (1909) published volume 1 of Die Naturlichen  Pflanzenfamilien that Hygrohypnum came in t o general usage. Brotherus also determined that the a f f i n i t i e s of Hygrohypnum were not with Hypnum, but with h i s new hypnaceous subfamily, the Amblystegiae. Brotherus (1923) elevated the subfamily to the rank of family. Grout (1931) also used the subfamily Amblystegiae. More importantly, he determined that Hygrohypnum could be subdivided i n t o four groups. These groups were given formal names, but no taxonomic rank. His groups were distinguished as follows: Group I, Palustreformes Leaves more than twice as long as broad, very concave with the upper margins i n f o l d e d , e n t i r e or s l i g h t l y serrulate above, a l a r c e l l s numerous. Group I I , A r c t i c i Leaves less than twice as long as wide, often nearly c i r c u l a r i n o u t l i n e , more or less concave, e n t i r e or s l i g h t l y s e r rulate at apex, margins usually plane. 14 Group I I I , Montani Stems without a c e n t r a l strand, leaves acuminate to apiculate, d i s t i n c t l y s e r r u l a t e above, s l i g h t l y decurrent, lower margins r e f l e x e d . Group IV, Ochracei An outer layer of stem c e l l s enlarged and hyaline, form-ing a hyaline sheath. Wijk, Margadant and Florschutz (1962) presented a l i s t of a l l publ-ished species and the sub s p e c i f i c taxa of Hygrohypnum. Wijk e t a l . (1969) emended that l i s t as follows: Hygrohypnum alpestre (Hedw.)_Loesk. H. alpinum (Lindb.) Loesk. var. v i r i s c e n s Amann var. tsurugizanicum (Card.) Nog. H. aureum Herz. H. b r a s i l i a n s e HBEZ. H_. caussequi (Ren. et-Gard.) Card. H. circinatum Herz. H. c l o s t e r i (Aust.) Grout H. cordifolium Okam. H_. coreanum Card. H. dilatatum (Wils.) Loesk. var. callineurum Amann var. duriusculum (Limpr.) Amann H. d o i i Sak. var. simplex Sak. H. e l l i p t i c u m Ther. H. entodontoides (Broth, e t Par.) Broth. 15 H_. eugyrium (Schimp.) Broth. ssp. subeugyrium (Ren. et Card.) Grout var. mackayi (Schimp.). Broth. var. miquelonense (Ren. et Card.) Grout var. nervosum (Roell) Podp. var. occidentale (Card. et. Ther.) Grout H. fontinaloides Chen H. glaciale Warnst. H. hedbergii P. Vard. H. liukiuense Sak. H. luridium (Hedw.) Jenn. ssp. pseudomontanum (Kindb.) Wijk et Marg. var. crassinervium(Baur.).Podp. var. ehlei (Am.) Wijk et Marg. var. malacocaulon (Herz.) Podp. var. obtusatum Podp. * nom. nud. var. pseudochraceum (Roth) Podp. var. subsphaericarpon (Brid.) C. Jans, in Podp. var. tenellum (Schimp.) Podp. H. lusitanicum (Schimp.) Corb. H. mizushimae Sak. H. molendinarium (Lam. etCand.) Wijk et Marg. H. molle (Hedw.) Losek. ssp. b e s t i i (Ren. et Card.) Grout var. b e s t i i (Ren. et. Card.) Hab. var. japonicurn Sak. var. pyrenaicum (Ren.) Podp. var. schimperianum (Lor.) Loesk. H. montanum (Lindb.) Broth. H. nichol s i i Grout H. norvegicum (Schimp.) Amann H. novae-caesarae (Aust.) Grout H. ochraceum (Wils.) Loesk. 16 H. pelichuense Williams H. peruviense Williams H. poecilophyllum Dix. H. polare (Lindb.) Loesk. var. pseudostramineum (Lindb.) Podp. H. purpurascens Broth. H. s m i t h i i (Sw. i n L i l j . ) Broth. var. goulardii-;:(;S chimp.) - Wijk et Marg. H. styriacum (Limpr.) Broth. H. s z a f e r i Szaf. H. tenquendamense Herz. H. validum Herz. Bartram (1965) added the most recently described species, a South American p l a n t which he c a l l e d Hygrohypnum f a l c i f o l i u m Bart. 17 METHODS OF THE MORPHOLOGICAL ANALYSIS The apparent inadequacy of those characters t r a d i t i o n a l l y employed i s d i s t i n g u i s h i n g species of Hygrohypnum indicated the need f o r a complete reassessment of a l l p o t e n t i a l morphological characters. Table 1 presents a l i s t o f eig h t y - s i x morphological characters which were examined during t h i s study. The assessment of the taxonomic value of these features was conducted by 1. the t r a d i t i o n a l examination of herbarium specimens and by 2. c u l t i v a t i n g l i v i n g specimens under conditions of uniform environ-ment. In those cases where material c o l l e c t e d i n the f i e l d bore mature sporophytes or where c u l t i v a t e d material produced sporophytes, the spores so derived were germinated and allowed to produce l e a f y gametophores. Thus, i n some cases i t was possible to compare gametophores grown from spores, gametophores derived from new vegetative growth from adult plants and the con t r o l herbarium specimens. 18 T a b l e 1 MORFHOLOGICAfc FEATORE8 HUBJ8CT TO RE* LYSIS Habit-. Color Stem Length Branching pattern Cross-section Cortical c e l l color Fseudcpavaphyllia Orientation to the substrate phizoids Position Color Call wail detail Frequency Abundance Leaves Shape Siie Symmetry Concavity Apex Curvature Toothing Decurrency Attitude upon the stem Changes in appearance between the wet and dry condition Arcolaticr. C e l l shape C e l l size Ce l l wall thickening' Cel l well discoloration C e l l v a i l p i t t i n g Papiilosity Regional variation Apical Median Marginal Basal Alar Sexuality Autoicous, dioicous, pseudo-parolccus Perichaetial leaves Outer, middle and inner leaves General features Si":ape Si-^e Attitude Apex Margins Curvature Toothing Coeta PericbaetlEl leaves con't. plication Areolation Papillosity Peiigonial leaves Shape Size Concavity Costa Margins Areolation Sporophyte Seta Length Color Cross-section Twisting Surface texture Capsule Shape Size Color Exothecial c e l l s Shape Size Wall thic-iriess Apophysal differentiation Constriction below the nouth Stomates Numbers Position Struct'ire Operculum Annulus • Peristome Exostome Color Segment length and width Striations Papillosity Endostcme Color Basal membrane height Segment length anc width Segment s p l i t t i n g Papillosity C i l i a Development Numbers Diameter Color VWll morphology 19 METHODS OF CULTIVATION A l l cultured plants, except those grown from spores, were maintained i n a r e f r i g e r a t e d growth room held between 6° and 9° C. A l l plants were grown on 4 layers of paper towel disks and moistened with a 50% so l u t i o n of Hoagland's culture medium (Hoagland and Arnold, 1938). Most plants were grown i n 90 mm X 19 mm p l a s t i c p e t r i dishes, while c e r t a i n larger specimens were grown i n 155 mm X 65 mm covered p l a s t i c dishes. The c u l -tures were illuminated by 6 banks of 60 inch long cool white fluorescent bulbs. Each bank bore 4 bulbs held at 38 inches above the plants. Addi-t i o n a l i l l u m i n a t i o n was provided by twelve 60 watt incandescent bulbs placed equidistant among the banks of fluorescent l i g h t s . The t o t a l i l l u m i n a t i o n was 530 foot-candles i n a 16/8 photoperiod. Cultures grown on paper toweling were frequently contaminated by u n i c e l l u l a r green algae and/or O s c i l l a t o r i a . Such contamination was con-t r o l l e d by p e r i o d i c a l l y washing the plants with tap water and gently scrub-bing them with a s t i f f a r t i s t ' s brush. When necessary several washed stems were transferred to new cult u r e dishes. Experimental plants grown from spores were maintained i n 90 mm X 20 mm glass p e t r i dishes i n 50% Hoagland's medium i n 2% Difco Bacto-Agar. They were maintained i n a growth room at 10° C on a 12/12 photoperiod. METHODS OF PREPARATION OF MATERIAL FOR MICROSCOPE EXAMINATION A l l materials were examined u t i l i z i n g microscope s l i d e preparations employing Hoyer's mounting medium. The Hoyer's was modified from Anderson (1954) so as to use 50 cc of gum arabic. 20 RESULTS OF THE MORPHOLOGICAL ANALYSIS Stem Anatomy The structure of the stem, as seen i n cross-^section, i s extremely important i n assessing both s i m i l a r i t i e s and d i f f e r e n c e s among the various species. The stem i s usually d i f f e r e n t i a t e d into three h i s t o l o g i c a l regions, but there may only, be two or as many as four. Usually the epidermal c e l l s and several concentric rows of c e l l s i n s i d e the epidermis are small, t h i c k -walled and yellow to red-brown i n c o l o r . This zone of c e l l s i s c a l l e d the cortex (Fig. 1 a - b). Inside the cortex there i s a broad region of large, thin-walled, usually hyaline c e l l s c a l l e d the medulla (Fig. 1 a - f ) . This medullary region may d i s c o l o r with age. At the very centre of the stem cross-section a group of small c e l l s may be abruptly d i f f e r e n t i a t e d from the medulla. These c e l l s are c a l l e d the c e n t r a l strand (Fig. 1 a - f) and i t i s r e g u l a r l y present i n most species. Hygrohypnum b e s t i i and H. subeugyrium are unusual for i n them the c e n t r a l strand i s only weakly de-o r veloped are. absent. Hygrohypnum montanum i s remarkable because i t lacks a centEal strand e n t i r e l y . In Hygrohypnum ochraceum, H. polare and H. eugyrium the epidermis of the stem i s d i f f e r e n t i a t e d from the adjacent cortex and i s c a l l e d a hyalo-dermis. In H. ochraceum the hyalodermis i s abruptly enlarged and t h i n -walled (Fig. 1 c ) . In older plants the t h i n outer wall i s u s u a l l y worn away leaving only the c a v i t y created by the inner tangential wall and the r a d i a l walls of each c e l l . The hyalodermis of H, polare i s s i m i l a r to that of H. ochraceum, but the enlarged c e l l s u s u a l l y do not completely encompass the stem (Fig. 1 d & e), i n which case the hyalodermis i s referred to as incomplete. A hyalodermis i s most poorly d i f f e r e n t i a t e d i n H. eugyrium 2 1 and is evident only because the outer tangential wall of the epidermis is slightly thinner and less pigmented than the radial and inner tangen-t i a l c e l l s walls (Fig. lne). 22 Fig. 1 a - f. V a r i a t i o n i n stem anatomy. a. K. duriusculum b. H. luridum c. H. ochraceum d. and e. H. polare f . H. eugyrium Scale: I lOOum i 2 4 Leaf Shape and Symmetry Leaf shape i s a very important character i n d i s t i n g u i s h i n g species of Hygrohypnum. In the past, the use of l e a f shape as a taxonomic c r i t -e r ion has been beset with two serious problems. In some species l e a f shape and l e a f symmetry are v a r i a b l e . A natural consequence of that var-i a b i l i t y i s that the v a r i a b i l i t y i n l e a f shape and symmetry of one species can overlap with that of another. I t i s understandable, then, that many people have confused many species by p l a c i n g too much r e l i a n c e on t h i s s i n g l e character. A second problem i s the employment of l e a f shape as a taxonomic c r i t e r i o n derives from the frequently ambiguous a p p l i c a t i o n of the terms used to'describe l e a f shape. The various attempts to standardize and quantify the d e s c r i p t i o n of l e a f shape seem to have yielded l i t t l e agreement among botanists. Much of the problem seems to involve the extent to which the nature of the l e a f apex a f f e c t s the l e a f shape. No attempt has been made here to resolve t h i s problem. For the purposes of t h i s study, Figig 2 i l l u s t r a t e s the usage of the various d e s c r i p t i v e terms as applied to l e a f shape i n Hygrohypnum. The examination of numerous herbarium specimens has shown that l e a f shape within a species v a r i e s within broadly definable l i m i t s . I t i s very s i g n i f i c a n t that those species that have been a v a i l a b l e for experimental study e x h i b i t the same basic v a r i a t i o n i n l e a f shape when grown i n c u l t u r e as they do under natural conditions. Based on data from herbarium material, Figures 3 - 6 d i r e c t l y compare the v a r i a b i l i t y i n l e a f shape of several frequently confused species. As a s t e r i s k at the base of a l e a f indicates the most or one of the most frequently encountered l e a f shapes f o r a given species. The leaves of species grown under natural and experimental condi-tions are compared i n Figures 7 - 9 . Lodge (1959, 1960) showed that i n Drepanocladus l e a f f a l c a t i o n was environmentally induced. Zales (1973) also established the var-i a b i l i t y of l e a f curvature i n P h i l o n o t i s . S i m i l a r l y , c u l t u r e studies on Hygrohypnum have shown l e a f f a l c a t i o n to be highly v a r i a b l e and i n -v a l i d as a taxonomic c r i t e r i o n . However, those species frequently pro-ducing f a l c a t e leaves e x h i b i t v a r i a b l e responses to experimental c u l t u r e . Under natural conditions Hygrohypnum eugyrium may produce s t r a i g h t or f a l c a t e leaves on the same stem or on d i f f e r e n t , but contiguous stems. Hygrohypnum montanum produces s t r a i g h t and f a l c a t e leaves on the same stem, but i n very s p e c i f i c l o c a t i o n s , In;culture, both H. eugyrium and H. montanum produce e x c l u s i v e l y s t r a i g h t leaves. Under both natural and experimental conditions Hygrohypnum styriacum produces both s t r a i g h t and f a l c a t e leaves. Certain specimens of Hygrohypnum ochraceum which produce e x c l u s i v e l y c i r c i n a t e - c a n i c u l a t e leaves i n nature, respond to experimental conditions by producing both c i r c i n a t e - c a n i c u l a t e leaves and s t r a i g h t and plane ones. Herbarium specimens reveal that Hygrohypnum  luridum can produce specimens with s t r a i g h t and/or f a l c a t e leaves on d i f f e r e n t plants, on d i f f e r e n t but contiguous stems or i n a l t e r n a t i n g sequences along the same stem. Experimental data on H. luridum are l e s s c l e a r because there i s l i m i t e d material a v a i l a b l e for study. I t has been shown that i n one c o l l e c t i o n non-contiguous stems, which bore s t r a i g h t or f a l c a t e leaves i n nature uniformly produced s t r a i g h t leaves i n c u l t u r e . The v a r i a b i l i t y i n l e a f shape and the obscuring e f f e c t of f a l c a t i o n upon l e a f shape d i c t a t e c e r t a i n procedures for evaluating l e a f shape. In a l l cases the leaves should be observed under a c o v e r s l i p with t h e i r adaxial side down. The l e a f shape exhibited by a p a r t i c u l a r specimen must be a r r i v e d at through the subjective assessment of at l e a s t twenty-26 f i v e leaves dissected from healthy stems. The l e a f shape i n plants bearing f a l c a t e leaves may be assessed i n several ways. Frequently, the leaves borne d o r s a l l y or v e n t r a l l y on prostrate stems are s t r a i g h t or l e s s f a l c a t e than those l a t e r a l l y placed. When only f a l c a t e leaves are a v a i l a b l e one must attempt to place the f a l c a t e l e a f adaxial side down under a c o v e r s l i p and extrapolate the t h e o r e t i c a l shape from the l e s s asymmetrical side of the l e a f . 27 Figv 2 a - g. Terminology of Leaf Shape a. Orbicular b. D b l o n g - E l l i p t i c Ci. Broadly ovate d. Ovate e. Oblong f. Oblong-lanceolate g. Lanceolate 28 9 V 29 F i g . 3 a - v. Comparison of leaf-shape v a r i a t i o n within and between species. a - e. K. alpinum f - i . H. duriusculum j - n. H. s m i t h i i o - r . H. b e s t i i s - v. H. molle Scale: a - j , S - V J I 1mm I ° " R'' I 2mm I , 30 31 Pig. 4 a - x. Comparison of leaf-shape v a r i a t i o n within and between species. a - c. H. norvegicum d - f . H. c o c h l e a r i f o l i u m g - j . H. styriacum k - s. H. luridum t - x. H. alpestre Scale: a c; I 0.5mm d j , t - x; k s; 1mm 33 F i g . 5 a - u. Comparison of leaf-shape v a r i a t i o n within and between species. a - d. H. polare e - 1. H. ochraceum in - u. H. eugyrium f Scale: I 1 m m I 34 35 F i g . 6 a - n. Comparison of leaf-shape v a r i a t i o n within and between species. a - c. H, subeugyrium from North America and Europe, d - f . H. subeugyrium from Japan, g - i . H. c l o s t e r i j - n. H. montanum Scale: 37 F i g . 7 a - t . Comparison of leaf-shape i n n a t u r a l l y growing plants of Hygrohypnum and t h e i r response to a r t i f i c i a l c u l t u r e . H. alpinum a - b. Natural plants; c - d. C u l t i v a t e d plants H. duriusculum e - f and i - j . Natural plants g - h and k - 1. C u l t i v a t e d plants H. molle m - ri. Natural plants o - p. C u l t i v a t e d plants H. b e s t i i q - r . Natural plants s - t . C u l t i v a t e d plants Scale: I 1mm I 38 39 F i g . 8 a - t . Comparison o f leaf-shape i n n a t u r a l l y growing plants of Hygrohypnum and t h e i r response to a r t i f i c i a l c u l t u r e . H. s m i t h i i a - b. Natural plants o - e. C u l t i v a t e d plants H. styriacum f - g. Natural plants h - j . C u l t i v a t e d plants H. luridum k - m. Natural plants n - p. C u l t i v a t e d plants H. luridum q. Natural plants r . Leaf derived from growth of vegetative plants. s - t . Leaves derived from gametophores grown from spores. Scale: 1 1mm 41 P i g . 9 a - t . Comparison of leaf-shape i n n a t u r a l l y growing plants Hygrohypnum and t h e i r response to a r t i f i c i a l c u l t u r e . H. ochraceum a - f. Natural plants g - j . C u l t i v a t e d plants H. eugyrium k - m. Natural plants n - p. C u l t i v a t e d plants H. montanum q - r . Natural plants s - t . C u l t i v a t e d plants Scale: a - p,- I ,—imm_ q - t ; 1 0.5mm 43 Leaf Apex The shape of the leaf apex, like that of the complete leaf, i s quite variable in some species and less so in others. In some species the shape of the leaf apex often overlaps with the shape exhibited by other species. However, toothing and curvature of the margin and concavity modify the character of the leaf apex so that i f often can be used as an effective character. The description of the shape of the leaf apex has been subjected to the same terminological ambiguity as has leaf shape. For the purposes of this study Fig. 1 0 illustrates the application to Hygrohypnum of the terms describing the shape of the leaf apex. Figure 1 1 b illustrates the abruptly acuminate leaf apex of Hygro- hypnum styriacum. Both Hygrohypnum luridum.and H. eugyrium have acute leaf apices whose margins are often inrolled imparting a weakly apicula.te appearance. The fine teeth at the leaf tips of H. eugyrium (Fig. 1 1 c & d) d i f f e r from the habitually entire leaf tips of H. luridum (Fig. 1 1 a). Hygrohypnum norvegicum and H. cochlearifolium have long been confused with each other. The sharply acute leaf apex of H. norvegicum differs from the rounded, obtuse apex of H. cochlearifolium (Fig. 1 2 a & b). The deep concavity of the leaf apex and i t s tiny squarrose apiculus make Hygrohypnum alpestre unique in the genus (Big. 1 2 f ) . The acute, but blunt and denticulate leaf apices which are regularly observed in H* subeugyrium are also unique to this species (Fig. 1 1 e s f ) , Hygrohypnum molle has been confused regularly with H. duriusculum. The leaf apex of the former is usually gradually tapered and acute with a slightly blunted point (Fig. 1 2 c). The apex of-H. duriusculum is rarely acute, but normally i t is rounded obtuse or rounded obtuse and 44 sometimes s l i g h t l y , but b l u n t l y apiculate (Fig. 12 d>. Hygrohypnum styriacum and H. luridum are often confused with each other. The abruptly acuminate apex of the former (Fig. 11 b) d i f f e r s from the acute apex of the l a t t e r (Fig. 11 a). 4 5 F i g . 10 a - h. Descriptive terminology f o r the shape of the l e a f apex, a - b. Rounded c. Obtuse d. Broadly acute e. Acute f. Acuminate g - h. Apiculate 46 47 Fig. 11 a - f . V a r i a t i o n i n the shape o f the l e a f apex. a. H. luridum b. H. styriacum c - d. H. eugyrium e - f . H. subeugyrium Scale: * I 100um I V 48 49 Fig. 12 a - f. V a r i a t i o n i n the shape of the l e a f apex. a. H. norvegicum b. H. c o c h l e a r i f o l i u m c. H. molle d. H. duriusculum e. H. montanum f. H. a l p e s t r e Scale: a - e; ' I 100um I  f ; I 0.5mm I 50 51-Costa The costa of Hygrohypnum i s v a r i a b l e and thus of l i m i t e d taxonomic value. The costa i s usually short and double, but may also be long and double or short and/or long and s i n g l e or sin g l e and forked. Each species, at some time, e x h i b i t s a sin g l e costa. However, the frequency of occurrence of a s i n g l e costa i s so low i n such species as Hygrohypnum eugyrium, H. montanum and H. molle that the costa can be considered as only short and double. Hygrohypnum polare i s unique i n the genus since i t s costa i s e x c l u s i v e l y s i n g l e , stout and percurrent or ending j u s t a few c e l l s below the apex. A short, double costa predominates i n Hygrohypnum duriusculum, but a slender, s i n g l e costa occurs r e g u l a r l y i n a few leaves. The costa of Hygrohypnum s m i t h i i i s always stout and although i t i s both short and double or s i n g l e , a s i n g l e costa predominates. Hygrohypnum luridum i s equally unique f or within the species the costa v a r i e s continuously through-out i t s complete range of v a r i a t i o n as exhibited i n the e n t i r e genus. Leaf Concavity Leaf concavity i s r e a d i l y apparent i n almost a l l species of Hygro-hypnum and i s one of the several features which unify the genus. However, i t i s useful i n d i s t i n g u i s h i n g species only i n cases where i t can be described as deeply concave. Deep concavity i s defined here not i n quan-t i t a t i v e terms, but i n terms of what can be seen i n a microscope s l i d e preparation when the l e a f has been placed adaxial side f a c i n g downward. If the concavity i s such that the weight of the c o v e r s l i p w i l l impart a curved f o l d that i s nearly p a r a l l e l to the; l e a f margin, as i n F i g . 13 b s d, or such that a s e r i e s of i r r e g u l a r or l i n e a r f o l d s form throughout the l e a f , as i n F i g . 13 d, then the l e a f i s interpreted as deeply concave. Figures 13 a & c i l l u s t r a t e the normal configuration of these same leaves. The asymmetrical curvature of f a l c a t e leaves imparts a channelled or caniculate concavity to the leaves. The differences shown i n such concav-i t y among falcate-leaved species i s not s i g n i f i c a n t . 53 F i g . 13 a - d. The nature of l e a f concavity. H. alpestre a. A l e a f as seen with a d i s s e c t i n g microscope. b. The same l e a f as seen i n a microscope s l i d e preparation. H. coc h l e a r i f o l i u m c. A l e a f as seen with a d i s s e c t i n g microscope. d. The same l e a f as seen i n a microscope s l i d e preparation. 55 Median Leaf C e l l s The broad v a r i a t i o n i n the dimensions of the median l e a f c e l l s within i n d i v i d u a l species and between d i f f e r e n t species renders these c e l l s of l i t t l e taxonomic usefulness. In most cases the extremes of median l e a f c e l l length vary independent of l e a f s i z e i n a given species. Only r a r e l y w i l l a comparison o f the average c e l l lengths of two species be h e l p f u l i n d i s t i n g u i s h i n g them from each other. A l l l e a f c e l l dimen-sions were measured from middle lamella to middle lamella. Marginal Leaf Cells The length of the median marginal leaf cells i s extremely useful in one case. Hygrohypnum be s t i i has often been mistaken for H. molle or H. duriusculum. The median marginal leaf cells of H_. best i i vary from 60 to 250 um long, while those of H. molle or H. duriusculum are rarely more than 55 um. Equally rarely one or two marginal cells in H. eugyrium and H. subeugyrium are from 65 to 70 um. The marginal cells of H. ochraceum are very plastic, ranging from 45 to 250 um. The marginal leaf cells of a l l other species are under 50 um. Figures 14 and 15 i l l u s t r a t e some variation observed in the marginal leaf c e l l s . 56 F i g . 14 a - g. V a r i a t i o n i n marginal l e a f c e l l s , a - b, H. alpinum c - d. H. duriusculum e - f . Jl. b e s t i i g - h. H. molle Scale: L_ 50 um J 58 F i g . 15 a - f . V a r i a t i o n i n marginal l e a f c e l l s , a - b. H. ochraceum c - d. H. eugyrium e - f . H. subeugyrium Scale: 1"' 50^tm | 60 Alar C e l l s The a l a r c e l l s are one of the most important taxonomic c r i t e r i a i n the genus. Yet, many of the problems within the genus can be traced to the f a c t that the a l a r c e l l s have not been c a r e f u l l y examined. This may be due, i n part, to the comments of Schimper (1853). He ®aid that the a l a r c e l l s are "wenig oder gar n i c h t ausgeholt und' das Z e l l h e t z deselben kaum von der ubrigen B l a t t b a s i s verschieden." His observation may have r e s u l t e d from the frequent occlusion of the a l a r c e l l lumens by dark cytoplasmic contents which obscure any observable d i f f e r e n t i a t i o n . I t i s true that the a l a r c e l l s of Hygrohypnum are not as dramatically d i s t i n c t as those of some species of C a l l i e r g o n or Hypnum. However, i t i s a lso true that there i s s u f f i c i e n t a l a r d i f f e r e n t i a t i o n i n some species of Hygrohypnum, such that when they are cleared, these c e l l s reveal several r e a d i l y observable patterns of d i f f e r e n t i a t i o n . Two p r e r e q u i s i t e s are absolutely e s s e n t i a l for the e f f e c t i v e assess-ment of the a l a r c e l l s . F i r s t , ten to twenty-five clean leaves must be c a r e f u l l y removed from a mature stem or primary branch segment. Secondly, the leaves should be placed adaxial side downward i n a drop of c l e a r i n g agent such as Hoyer's, lacto-phenol or KOH. Several d i f f e r e n t expressions of a l a r d i f f e r e n t i a t i o n are evident i n the genus. Each expression i s the r e s u l t of a combination of 1. c e l l shape, 2. c e l l s i z e , 3. r e l a t i v e numbers of c e l l s , 4. w a l l thickness, 5. excavation and 6. d i s c o l o r a t i o n . Quadrate, short rectangular or i r r e g u l a r shapes are those most f r e -quently encountered among the a l a r c e l l s of Hygrohypnum. C e l l s of such shapes d i f f e r markedly from the rhomboid, fusiform or l i n e a r flexuose shapes of median l e a f c e l l s . However, the recognition of a d i s c e r n i b l e group of a l a r c e l l s depends upon the r e l a t i v e numbers of quadrate or short rectangular c e l l s and a subjective assessment of how abruptly they d i f f e r from surrounding c e l l s . A few i s o l a t e d quadrate to short rectang-u l a r c e l l s may occur i n Hygrohypnum molle (Fig. 16 a), but the bulk of the c e l l s are s i m i l a r to the l i n e a r or long rectangular basal or lower median l e a f c e l l s . Such a condition i s interpreted here as e x h i b i t i n g no a l a r d i f f e r e n t i a t i o n . Figures 16 b, c & d i l l u s t r a t e r e s p e c t i v e l y the a l a r regions of H. cochlearifolium, H. norvegicum and H. c l o s t e r i . In these species there are several quadrate to short rectangular c e l l s i n the a l a r region. However, the t r a n s i t i o n from the surrounding l i n e a r or fusiform c e l l s i s so gradual that a d i s t i n c t group of c e l l s i s not apparent. This condition d i f f e r s markedly from that of H. molle, but a l l of these taxa are interpreted as lacking any a l a r d i f f e r e n t i a t i o n . In addi t i o n , Hygrohypnum b e s t i i , H. s m i t h i i , H_. styriacum and H. montanum are s i m i l a r l y interpreted as e x h i b i t i n g no a l a r d i f f e r e n t i a t i o n , A c l e a r l y d i s c e r n i b l e group of numerous quadrate tea short rectangu-l a r a l a r c e l l s occurs i n Hygrohypnum polare (Fig. 17 a) and H, luridum (Fig, 17 c ) . Figure 18 a i l l u s t r a t e s a s i m i l a r s i t u a t i o n i n H, duriusculum, which d i f f e r s i n the more frequent occurrence of i r r e g u l a r c e l l s and thicker walls. The a l a r c e l l s of H. polare are very constant, but those of H, luridum and H. duriusculum are v a r i a b l e . While H. luridum v a r i e s l i t t l e i n the r e l a t i v e numbers of a l a r c e l l s , H. duriusculum may e x h i b i t as few as 3 v e r t i c a l , p a r a l l e l rows of a l a r c e l l s , i ncluding the l e a f margins (Fig. 18 b). This contrasts with the s i t u a t i o n seen i n F i g . 18 a. In Hygrohypnum duriusculum t h i s v a r i a t i o n occurs i n both robust and depauperate plants, p a r t i c u l a r l y those from Western North America. I t i s t h i s v a r i a -b i l i t y that has no doubt contributed to the confusion between H, duriusculum 62 and H. molle and emphasizes the need to observe numerous leaves before making a judgement. The a l a r c e l l s of H. luridum and H. duriusculum vary further i n c e l l wall thickness, excavation (Pig. 17 d s 18 c) and c e l l wall d i s c o l o r a t i o n . Abrupt c e l l enlargement or i n f l a t i o n i s another frequently encount-ered mode of a l a r d i f f e r e n t i a t i o n . An abrupt increase i n c e l l s i z e i s interpreted here to mean at l e a s t a two f o l d increase i n length and/or width r e l a t i v e to the adjacent c e l l s . This condition i s apparent i n Hygrohypnum eugyrium (Fig. 19 a) and H. alpinum (Fig. 19 b). In rare instances a recognizable group of a l a r c e l l s may occur as a gradual t r a n s i t i o n i n c e l l shape and s i z e from the surrounding median and basal c e l l s . Figure 19 d i l l u s t r a t e s a small group of such c e l l s , while Figure 19 c i l l u s t r a t e s a l a r g e r group. These two states pepresent opposite ends of the spectrum of a l a r d i f f e r e n t i a t i o n i n Hygrohypnum  ochraceum. Another expression of a l a r d i f f e r e n t i a t i o n may not be conveniently r e f e r r e d to a geneasal pattern, fiigure 18 d i l l u s t r a t e s a s i t u a t i o n i n which 1 or 2 rows of enlarged, incrassate, d i s c o l o r e d c e l l s extend across the l e a f base at the l i n e of i n s e r t i o n . Just above t h i s basal row and along the l o a f margin i s a v a r i a b l e number of quadrate or i r c e g u l a r c e l l s . This a l a r c e l l configuration i s t y p i c a l of Hygrohypnum subeugyrium. 63 Fig. 16 a » d. V a r i a t i o n i n a l a r c e l l d i f f e r e n t i a t i o n . a. H. molle b. H. c o c h l e a r i f o l i u m c. H. norvegicum d. H. c l o s t e r i Scale: 1 1 0 0 u m i v A 64 65 F i g . 17 a - d. V a r i a t i o n i n a l a r c e l l d i f f e r e n t i a t i o n , a - b. H. polare c - d. H. luridum 66 67 F i g . 18 a - d. V a r i a t i o n i n a l a r c e l l d i f f e r e n t i a t i o n , a - c. H. duriusculum d. H. subeugyrium Scale: I 100 um 68 69 F i g , 19 a - d. V a r i a t i o n i n a l a r c e l l d i f f e r e n t i a t i o n . a. H. eugyrium J b. H. alpinum C o - d. H. ochraceum Scale: 1 um | 70 71 Response to Drying Upon drying the leaves of most species e x h i b i t l i t t l e change i n o v e r a l l appearance or i n t h e i r a t t i t u d e upon the stem. A few, however, undergo very dramatic changes, which when used with other characters can be useful i n d i s t i n g u i s h i n g c e r t a i n taxa. Figures 20 & 21 compares the moist and dry conditions i n some of these plants. Shrinkage i n l e a f width i s the most common response to drying and r e s u l t s i n several recognizable patterns of l e a f convolution. Figure 20 b i l l u s t r a t e s two such patterns. One pattern where the l e a f margins i n r o l l can be seen i n a l e a f near the middle of the f i g u r e * The second pattern can be seen i n the upper h a l f of the same f i g u r e . Here the leaves have responded by twisting about t h e i r midline. A s i m i l a r configuration i s observable i n F i g . 20 d. A t h i r d pattern can be seen i n the upper h a l f of F i g . 20 d. In t h i s case the margins i n the lower h a l f of the l e a f be-come squarrose. These drying responses characterize Hygrohypnum duriusculum. Figures 21 b & 21 e i l l u s t r a t e the drying response of Hygrohypnum  b e s t i i . Here severe l e a f contortion does not accompany shrinkage. Instead, the leaves remain nearly plane or are s l i g h t l y twisted. In such cases the reduction i n apparent l e a f surface area i s more evident. Hygrohypnum molle has long been confused with H. duriusculum and H. b e s t i i . However, H. molle undergoes very l i t t l e change i n appearance upon drying (Fig, 21 c ) , A s l i g h t amount of shrinkage and t w i s t i n g i s evident, but the leaves tend to r e t a i n t h e i r imbricate to s l i g h t l y spreading a t t i t u d e . For a l l i t s remarkable polymorphism, Hygrohypnum luridum shows l i t t l e change i n appearance upon drying. An e n t i r e l y d i f f e r e n t response to drying i s seen i n F i g . 62 e. Here the leaves are f a l c a t e and folded along t h e i r midline into a caniculate channel. Shrinkage i n l e a f width i s n e g l i g i b l e , but the l e a f apex undergoes a c h a r a c t e r i s t i c t w i s t i n g to resemble a f i l i f o r m l e a f t i p . This i s a common response i n Hygrohypnum ochraceum. The leaves of Hygrohypnum c l o s t e r i are widely spaced along t h e i r stems. In the moist condition the leaves are spreading (Fig. 76 d). Upon drying the leaves shrink and twist and accentuate the d i s t a n t spacing by becoming almost squarrose (Fig. 76 c ) . 73 Fig. 20 a - h. Variation i n a l t e r a t i o n i n habit from wet to dry conditions i n morphologically d i f f e r e n t shoots, H. duriusculum a. Moist; b. Dry c. Moist? d. Dry e. Moist; f. Dry g. Moist; h. Dry 74 75 F i g . 21 a - e. V a r i a t i o n i n a l t e r a t i o n i n habit from wet to dry donditions i n morphologically d i f f e r e n t shoots. H, b e s t i i a. Moist; b. Dry d. Moist; e. Dry H. molle c. Moist; unchanged i n the dry condition. 77 Sexuality The problems imposed on bryophyte taxonomy by the infrequency of sexual plants i s well known. However, i n Hygrohypnum, the sexual con-d i t i o n provides c l e a r d i s c o n t i n u i t i e s between c e r t a i n species or corres l a t e s with d i s c o n t i n u i t i e s evident from other characters. A l l but four species of Hygrohypnum are autoicous. Hygrohypnum  b e s t i i , H. ochraceum and H. polare are dioicous. The male and female plants of H. b e s t i i and H, polare are s i m i l a r i n appearance. The male plants of H, ochraceum are more slender and t h e i r leaves.more widely spaced than i n the females. Hygrohypnum styriacum e x h i b i t s the most unusual sexual condition i n the genus. This species has a si n g l e perigonium subtended by 2 to 3 p e r i c h a e t i a which i n turn are subtended by 1 to 3 small, scale l i k e bracts (Fig. 13 a & b). This complete c l u s t e r of sexual inflorescences i s jfeorne i n the a x i l of a f o l i a g e l e a f . The perigonium may have as many as four leaves or as few as one. When only one p e r i g o n i a l l e a f i s present the antheridia d i r e c t l y abut the outer p e r i c h a e t i a l l e a f immediately adjacent. In those cases where the antheridia are enclosed by 2 to 4 pe r i g o n i a l leaves the o v e r a l l d i s p o s i t i o n o f the sexual inflorescences d i f f e r s from t y p i c a l autoiecy only i n immediate proximity to one another. When only 1 p e r i g o n i a l l e a f i s present, however, the s i t u a t i o n i s remin-escent of paroicy. The term pseudo-paroicy i s offe r e d to describe t h i s s i t u a t i o n . 78 F i g . 22 a - b. The pseudo-paroicous inflorescence of Hygrohjypnum  styriacum. a. The inflorescence as i t appears n a t u r a l l y . b. A diagrammatic representation of the inflorescence. 79 80 P e r i c h a e t i a l Leaves The p e r i c h a e t i a l leaves e x h i b i t a number of useful characters that strengthen the d i s c o n t i n u i t i e s between c e r t a i n taxa. Hygrohypnum alpinum and H. molle stand apart from other species by the p a p i l l a e they e x h i b i t on the abaxial surface of some a p i c a l c e l l s of the inner p e r i c h a e t i a l leaves (Fig, 23 a & b). These p a p i l l a e are formed by the o v e r r i d i n g of the d i s t a l end walls. Occasionally one or two p a p i l l a e have been observed i n the same p o s i t i o n of the inner p e r i c h a e t i a l leaves of H. cochleaeifolium. A l l other species of Hygrohypnum have smooth inner p e r i c h a e t i a l l e a f c e l l s . Hygrohypnum c l o s t e r i and H. montanum s i m i l a r l y stand apart from the bulk of the genus. Their inner p e r i c h a e t i a l leaves are e i t h e r plane or very weakly p l i c a t e . The p e r i c h a e t i a l leaves of a l l other species have 2 to 4 strong p l i c a e . (See F i g . 25 f, g & h) A plane inner p e r i c h a e t i a l l e a f margin i s the general condition i n the genus. Hygrohypnum coc h l e a r i f o l i u m and H. s m i t h i i d i f f e r dramatically from t h i s i n the e x h i b i t i o n of strongly recurved margins (Fig. 24 d, e & f ) . The costa i s v a r i a b l e i n the inner p e r i c h a e t a i l leaves of most species °f Hygrohypnum. However, the inner p e r i c h a e t i a l leaves of H. polare, l i k e the vegetative leaves, e x h i b i t a strong, s i n g l e percurrent costa (Fig. 25 c ) , The vegetative leaves of H. closfeeri are usually s i n g l y costate, but a few short and double costae do occur. I t s inner p e r i c h a e t i a l leaves are unusual f o r the costa i s e x c l u s i v e l y s i n g l e (Fig. 25 h). The shape of the apex of the inner p e e i c h a e t i a l l e a f apex i s v a r i a b l e . However, i t may be of some value i n c e r t a i n cases. The most common shape of the inner p e r i c h a e t i a l l e a f apex i s acute. The acuteness v a r i e s from abrupt i n Hygrohypnum alpinum and H. c o c h l e a r i f o l i u m (Fig. 24 a & f) to 81 gradually so i n most species. Hygrohypnum s m i t h i i d i f f e r s by being rounded or obtuse (Fig. 23 c & 24 d ) . R e f l e c t i n g the shape of the apex of i t s vegetative leaves, H. styriacum has a s l i g h t l y aeuminate -inner-p e r i c h a e t i a l l e a f apex (Fig. 25 d). The inner p e r i c h a e t i a l leaves of H * c l o s t e r i are also s l i g h t l y accuminate (Fig. 25 h), a s t r i k i n g de-parture from the acute, but blunt apex i n the vegetative leaves. The toothing along the margin and i n the apex of the inner p e r i -c h a e t i a l leaves tends to r e f l e c t the s i t u a t i o n i n the vegetative leaves, but i s generally too v a r i a b l e to be u s e f u l . 82 F i g . 23 a - c. V a r i a t i o n i n the p e r i c h a e t i a l l e a f apex. a. H. molle b. H. alpinum c. H. s m i t h i i Scale: L 100um \ 8 4 F i g . 24 a - f. V a r i a t i o n i n the p e r i c h a e t i a l leaves. a. H. alpinum b. H. duriusculum c. H. molle d. H. s m i t h i i e - f. H. cochlearifolium 86 F i g . 25 a - g. V a r i a t i o n i n the p e r i c h a e t i a l leaves, a - b. H. luridum c. H. polare d - e. H. styriacum f - g. H. montanum h. H. c l o s t e r i Sporophyte The sporophyte o f f e r s few characters that are of value i n d i s t i n -guishing species of Hygrohypnum. The sporophytes are not uniform, but the di f f e r e n c e s they e x h i b i t are i n such v a r i a b l e features as capsule and seta length or c o l o r . However, the annulus and the endostomial c i l i a are useful i n c e r t a i n cases. A l l Hygrohypnum species except H. luridum have a well developed annulus. The absence of the annulus i n H. luridum provides a sharp contrast with H- styriacum, a species with which H. luridum i s often confused. Hygrohypnum duriusculum has 1 to 3 well developed c i l i a between adjacent endostomial segments, while i n H. alpinum and H. molle the c i l i a are rudimentary or wanting. Hygrohypnum cochlearifolium also d i f f e r s from H. molle by i t s 2 to 3 well developed c i l i a , which unfortunately f a l l away very ea r l y . 89 TAXONOMIC TREATMENT Hygrohypnum Lindb., Act. Soc. Sc. Fenn. 10:277. 1872 Hypnum Hedw. sect. A l p e s t r i a Hub., Muse. Ger, 629. 1833. Hypnum Hedw. Sect. P a l u s t r i a De Not., S y l , Muse. 45. 1838. Limnobium Schimp., Bryol. Eur. 6:65. 1853, hom. i l l e g . Hypnum Hedw. subg. Limnobium (B.S. & G.) S u l l , i n Gray, Man. Bot. N. U. S. ed. 2:677. 1856. Stereodon B r i d . sect. Limnobium (B.S. & G.) Mitt., J . Linn. Soc. Bot. 8:42, 1864. Amblystegium B.S, & G, subg. Hygrohypnum (Lindb.) Lindb., Musci Scand. 33. 1879. Hypnum Hedw. sect. Limnobium (B.S. & G,) Ren., Rev. Bryol. 10(3): 41. 1883. Hypnum Hedw. subg. Hypnum Boul. sect. Limnobium (B.S, & G.) Boul., Muse. France. 1884. Hypnum Hedw. sect. Eu-Limnobia Du Bat, B u l l . Trim. Soc. Bot. Lyon 3:54. 1885. Hypnum Hedw. sect. Hetero-Limnobia Du Bat, B u l l . Trim. Soc. Bot. Lyon 3:55. 1885. Ca l l i e r g o n (Sull.) Kindb. i n part, Canad. Rec. S c i . 6(2):72. 1894. Amblystegium B.S. & G. sect. Hygrohypnum (Lindb.) Braithw., B r i t . Moss F I . 3:17. 1898. Ca l l i e r g o n (Sull.) Kindb. sugb. Limnobion Kindb., Eur. N. Am. Bryin. 1:79. 1897. C a l l i e r g o n (Sull.) Kindb. subg, Pseudo-Limnobion Kindb., Eur. N. Am. Bryin. 1:80, 1897. 9 0 C a l l i e r g o n (Sull.) Kindb. subg. Pseudo-Limnobion Kindb. sect. Badiaformia Kindb. i n part., Eur. N. Am. Bryin. 1:80. 1897. Ca l l i e r g o n (Sull.) Kindb. subg. Pseudo-Limnobion Kindb. sect. Ochraceiformia Kindb., Eur. N. Am. Bryin. 1:80. 1897. Ca l l i e r g o n (Sull.) Kindb. subg. Pseudo-Limnobion Kindb. sect. Molliformia Kindb., Eur, N. Am, Bryin. 1:80, 1897. Ca l l i e r g o n (Sull.) Kindb-. subg. Pseudo-Limnobion Kindb. sect. Montaniformia Kindb., Eur. N. Am. Bryin. 1:80, 1897. Names treated as synonyms elsewhere, but for which the l i t e r a t u r e was unavailable for assessment during t h i s study. Hypnum Hedw. subsect. Palustr&a (fie NotJ Rabenh,, Deutsch, Krypt. PI. 2(3);270. 1848. Hypnum Hedw. subg. Hygrohypnum (Lindb.) S c h i f f n . , Lotos Prag, 55:211. 1907. Hypnum Hedw. sect. Hygrohypnum (Lindb.) Par., Ind. Bryol. 589. 1896, A Generic Description of Hygrohypnum Plants usually growing on i r r i g a t e d rock and stones i n and beside small, c o l d , s w i f t l y running mountain streams or r i v u l e t s , sometimes i n large r i v e r s , r a r e l y at low elevations i n temperate zones, r a r e l y on wood, or submerged i n s t i l l water or on damp, shaded c l i f f ledges? plants var-i o u s l y forming loo s e l y to very t i g h t l y woven, appressed mats or ascending patches, mats or r a r e l y t u r f s ; c o l o r v a r i a b l e , dirty-yellow, yellow-brown, yellow-green, b r i g h t or dark, dull-green, olivaceous-green, blackish-green, most species e x h i b i t i n g a rusty mottling or variegation, r a r e l y one ox two species e x h i b i t a b r i g h t m e t a l l i c red or bronze pigmentation, a l l species be-coming yellow-brown, brown, reddish-brown or blackish-brown with age; stems usually 1 to 15 cm long, r a r e l y to 20 cm, procumbent or ascending at the t i p s , l e a f y throughout or becoming denuded i n the o l d e s t extremities; branching i r r e g u l a r , a r i s i n g from the a x i l s of l a t e r a l or v e n t r a l leaves, procumbent, ascending, r a r e l y erect or f a s t i g a t e ; Stem cross-sections u s u a l l y revealing 2 to 4, sometimes 5 rows of small, thick-walled, yellow-ish-brown, brown or reddish-brown c o r t i c a l c e l l s , r a r e l y e x h i b i t i n g an i n -completely d i f f e r e n t i a t e d or well ^ .developed row'' of s l i g h t l y l e s s thick or i n f l a t e d , thin-walled outer c o r t i c a l c e l l s , medullary c e l l s l arger, u s u a l l y hyaline and thinner walled, often becoming discolored and thicker walled with age? c e n t r a l strand poorly to well developed, r a r e l y e n t i r e l y absent; r h i z o i d s reddish-brown, a r i s i n g from the base of v e n t r a l stem leaves or the v e n t r a l side of the p e r i c h a e t i a . Leaves v a r i a b l e , usually o r b i c u l a r , broadly e l l i p t i c , broadly ovate or ovate, ovate-lanceolate, oblong or oblong-lanceolate, r a r e l y lanceolate; usually s t r a i g h t , often f a l c a t e and/or secund, sometimes squarrose recurved; apex broadly rounded or obtuse to acute, r a r e l y s l i g h t l y acuminate or broadly rounded and/or obtuse with an apiculus, a p i c a l margins usually e n t i r e or f i n e l y denticulate, sometimes s e r r u l a t e , r a r e l y a few f i n e teeth at the apex or r a r e l y coarsely denticulate, a p i c a l margins usually plane, sometimes i n r o l l e d ao as to appear apiculate, r a r e l y recurved or reflexed as an apiculus; margins of the lamina usually e n t i r e or f i n e l y and i r r e g u l a r l y denticulate, :< r a r e l y s e r r u l a t e throughout, usually plane, sometimes infolded as wing along one or both sides of the l e a f , r a r e l y narrowly recurved; concavity v a r i a b l e , usually shallow to deeply so, r a r e l y almost plane; costa v a r i a b l e , usually short and double with one or both arms ending below midleaf, sometimes long and double with one or both arms extending beyond midleaf, or s i n g l e , slender or stout, usually ending between 1/2 to 3/4 of the l e a f length, r a r e l y pre-9 2 current, sometimes forked one or twice, nearly a l l the c o s t a l v a r i a t i o n may be observed within a s i n g l e plant; leaves abruptly narrowed at the i n s e r t i o n , sometimes clasping the stem when the a l a r c e l l s are excavated; leaves crowded to distant; a t t i t u d e upon the stem when wet v a r i a b l e , usually appressed imbricate or tumid julaceous, or spreading or r a r e l y wide spreading, upon drying the leaves may change l i t t l e i n a t t i t u d e or undergo varying degrees of l a t e r a l shrinkage and contortion. Aceolation v a r i a b l e , a l l c e l l s smooth, median l e a f c e l l s short rhom-b i c or fusiform to long, l i n e a r - f l e x u o s e , u s u a l l y l i n e a r flexuose, c e l l s u s ually or uniform width; sometimes unusually wide c e l l s are i r r e g u l a r l y interspersed, walls usually t h i n , r a r e l y thickened; toward the l e a f apex the c e l l s generally become shorter, fusiform rhombic or oval, sometimes changing l i t t l e from the median c e l l s ; marginal l e a f c e l l s u s ually l e s s than 60 urn long, r a r e l y exceeding 60 urn, but when doing so often r e g u l a r l y ex-ceeding 100 urn; basal c e l l s v a r i a b l e , becoming gradually wider, longer or shorter than the median c e l l s or changing l i t t l e , becoming thicker walled or changing l i t t l e , p i t t e d or unpitted, hyaline or v a r i o u s l y pigmented par-t i c u l a r l y when thick-walled, yellow-brown, reddish-yellow, brown or reddish-brown; a l a r c e l l s v a r i a b l e , u n d i f f e r e n t i a t e d or v a r i o u s l y forming small and i r r e g u l a r to large groups of quadrate, short rectangular or i r r e g u l a r c e l l s or v a r i a b l e groups or enlarged and thin-walled to i n f l a t e d c e l l s , plane or excavated, hyaline or yellow^brown, brown, reddish-brown, r a r e l y b r i g h t red. Plants autoicous, dioicous or pseudo-paroicous; p e r i g o n i a l leaves ovate, laminal c e l l s smooth, ecostate, margins e n t i r e or weakly s e r r u l a t e , concave-imbricate enclosing 4 to 10 oblong-^elliptic antthfe'tii&dia and several hyaline, u n i s e r i a t e periphyses; outer and middle p e r i c h a e t i a l leaves var-93 i a b l e , ovate to ovate-lanceolate, costa absent, short and double or si n g l e to midleaf, squarrose-reflexed i n the upper h a l f , laminal c e l l s smooth; inner p e r i c h a e t i a l leaves erect, broadly, long l i n e a r or t r i -angular lanceolate, usually 2 to 4 deep p l i c a e , r a r e l y plane or nearly so, costa v a r i a b l e , absent, short and double, long and double or s i n g l e and/or forked, f a i n t or stout, margins usually plane, r a r e l y recurved, e n t i r e or f i n e l y to coarsely s e r r u l a t e , e s p e c i a l l y i n the apex, apex obtusely acute to long tapering acute, laminal c e l l s smooth, r a r e l y a few c e l l s i n the l e a f apex are p a p i l l o s e on the abaxial l e a f surface by means of d i s t a l l y overlapping endwalls. Seta 6 to 31 mm long,, usually 10 to 20 mm, erect or s l i g h t l y i n c l i n e d when moist, smooth, color v a r i a b l e , yellowish-orange, yellowish-red, reddish-brown, dark b r i g h t red; cross sections revealing 2 to several rows of small, thick-walled c e l l s , medullary c e l l s s l i g h t l y l a r g e r , thin-walled, becoming thi c k e r walled with age; c e n t r a l strand broad, well developed; upon drying the seta twists i n various d i r e c t i o n s . Capsules 1 to 3 mm long, ovoid to o b l o n g - c y l i n d r i c a l , erect and symmetri-c a l or i n c l i n e d and s l i g h t l y to strongly arcuate; color v a r i a b l e , yellow-brown, brown, or reddish-brown; exothecial c e l l s v a r i a b l e , rounded, quadrate, short rectangular, i r r e g u l a r , thick or t h i n walled; d i f f e r e n t i a t e d neck present or absent,, stomates s u p e r f i c i a l on the neck and lower capsule, v a r i a b l e i n number, 7 to 30; annulus usually of 2 to 3 rows of c e l l s , some-times 4, r a r e l y absent; operculum conic or conic apiculate; c a l y p t r a -cu c u l l a t e ; capsule response to drying v a r i a b l e , generally shrinking, remain-ing erect or becoming strongly arcuate c y l i n d r i c , the neck when d i f f e r e n t i a t e d becoming wrinkled upon drying, capsule strongly contracted beneath the mouth or sometimes hardly at a l l . Peristome double, exostome of 16 teeth, pale yellow, yellow-brown, or 94 l i g h t reddish-brown below, hyaline i n the upper h a l f , each segment i s h o r i z o n t a l l y s t r i a t e i n the lower 1/2 to 1/3, f i n e l y p a p i l l o s e i n the upper 1/3 to 1/2; endostome o f 16 hyaline to pale yellow teeth, f i n e l y p a p i l l o s e to almost smooth, frequently cracked along the keel, e s p e c i a l l y i n the lower h a l f ; 1 to 3 radimentary to well developed c i l i a between adjacent segments, basal membrane 2 to 4 t i e r s i n height. Spores usually dusky yellow or yellow-green, f i n e l y p a p i l l o s e . 95 Key to the species of Hygrohypnum 1. Stem cross-section revealing an epidermis of small thick-walled c e l l s which are s i m i l a r to the subadjacent c o r t i c a l c e l l s . . 4 1. Stem cross-section revealing an epidermis i n which some or a l l of the c e l l s are enlarged and thin-walled r e l a t i v e to the sub-adjacent c o r t i c a l c e l l s or some c e l l s have a s l i g h t l y thinner and less pigmented outer tangential c e l l wall compared with the other epidermal c e l l s walls and the subadjacent c o r t i c a l c e l l s 2 2. Costa uniformly strong and s i n g l e , percurrent H. polare 2. Costa short and double, double to midleaf or i f s i n g l e and/or forking, then ending well before the apex 3 3. A l a r c e l l s i n f l a t e d , forming a d i s t i n c t group of c e l l s , often be-coming red or reddish-brown with age; l e a f apex acute...H. eugyrium 3. A l a r c e l l s wider and shorter than adjacent c e l l s , but neither i n -f l a t e d nor abruptly d i f f e r e n t from them, marginal a l a r c e l l s i n -creasing i n length d i s t a l l y from the point of i n s e r t i o n , hyaline or yellowish? never red; l e a f apex blunt H. ochraceum 4. Leaves a l l s t r a i g h t ; sometimes secund. 5 4. Leaves f a l c a t e or some leaves on the same or d i f f e r e n t stems with-i n the same specimen f a l c a t e and/or s t r a i g h t .....18 5. Leaves broadly ovate to o r b i c u l a r 6 5. Leaves ovate to oblong-ovate or ovate-lanceolate ...11 6. Median marginal l e a f c e l l s 60 um or longer H. b e s t i i 6. Median marginal l e a f c e l l s r a r e l y longer than 55 um .....7 7. Ala r c e l l s c l e a r l y d i f f e r e n t i a t e d , e i t h e r thin-walled or incrassate 8 7. A l a r c e l l s u n d i f f e r e n t i a t e d or a few quadrate or short rectangular c e l l s which are incrassate or thin-walled 9 8. A l a r c e l l s thin-walled, u s u a l l y hyaline, enlarged, rounded rectan-gular, forming a rectangular group whose long axis p a r a l l e l s the le a f margins; ineer p e r i c h a e t i a l leaves p a p i l l o s e on the .\baxial surface near the apex. „H. alpinum 8. A l a r c e l l s incrassate, c l e a r l y pigmented i n older leaves, quadrate, short rectangular or i r r e g u l a r , forming an i r r e g u l a r group; inner p e r i c h a e t i a l leaves smooth , H. duriusculum 96 9. Costa usually single, stout, to midleaf or slightly beyond, sometimes forked and/or stout, short and double; plants very coarse and r i g i d H. smithii 9. Costa almost exclusively short and double, i f single, then the costa i s slender and the plants are soft 10 10. Leaves deeply concave to cochleariform, usually 0.8 to 1.2 mm long, apex obtuse or broadly rounded, inner perichaetial leaf margins entire and recurved; endostomal c i l i a 2 to 3. H. cochlearifolium 10. Leaves concave, but never cochleariform, usually 1.0 to 1.7 mm long, apex tapering to an acute, but blunt point; inner peri-chaetial leaf margins coarsely denticulate and plane; endostomal c i l i a rudimentary or wanting H. molle 11. Alar c e l l s clearly differentiated, either inflated and mostly thin-walled or smaller, incrassate and quadrate to short rectangular.... 12 11. Alar cells undifferentiated or with but a few quadrate to short rec-tangular cells which do not form a recognizable group 14 12. Leaf apex narrowly recurved along the margin and reflexed as a small apiculus, especially in leaves at or near stem or branch tips; leaves deeply concave, especially near the apex H. alpestre 12. Margins of leaf apices plane or variously inrolled, never recurved./ apex never forming a reflexed apiculus.... 13 13. Leaf apices always acute and entire H. luridum 13. Someileaf apices with a few fine teeth or obtuse and distinctly denticulate , .H. subeugyrium 14. Leaf, apex abruptly acuminate, tapering to a slender tip; plants pseudo-paroicous. H. styriacum 14. Leaf apex obtuse or acute, with or without a blunt tip 15 15. Costa predominantly single to midleaf or beyond, sometimes short and double.... 16 15. Costa usually short and double, rarely single to midleaf 17 16. Leaf apex obtuse; plants coarse; inner perichaetial leaves plicate, margins recurved H. smithii 16. Leaf apex acute with a blunt tip; plants coarse; inner perichaetial leaves never plicate, margins plane H. closteri 17. Leaf apex entire; leaves usually 0.5 to 0.8 mm long...H, norvegicum 97 17. Margin of the l e a f apex uneven to denticulate; leaves usually 1.0 to 1.7 iron long H_. molle 18. Leaves e x c l u s i v e l y f a l c a t e 19 18. Falcate and s t r a i g h t leaves occurring simultaneously on the same stem or on d i f f e r e n t stems within the same specimen*, 23 19. A l a r c e l l s u n d i f f e r e n t i a t e d from adjacent c e l l s 20 19. Alar c e l l s well developed; small, numerous, quadrate to short-rec-tangular, incrassate or i n f l a t e d ; plane or excavated 21 20. Leaf margin f i n e l y to coarsely s e r r u l a t e , e s p e c i a l l y i n the apex, and narrowly recurved, p a r t i c u l a r l y i n the lower h a l f ..of the l e a f H. montanum 20. Leaf margin always e n t i r e and plane H_. styriacum 21. A l a r c e l l s i n f l a t e d H. eugyrium 21. Alar c e l l s small, quadrate to short rectangular, incrassate 22 22. Leaf apex always acute, the margin e n t i r e H. luridum 22. Some l e a f apices.; obtuse and d i s t i n c t l y denticulate or acute with a few f i n e teeth H_. subeugyrium 23. Leaf apex always e n t i r e 24 23. Leaf apices- bearing a few f i n e teeth ...25 24. Leaf apex acute; a l a r c e l l s numerous, quadrate to short rectangular; annulus absent; plants autoicous , H. luridum 24. Leaf apex abruptly acuminate; a l a r c e l l s u n d i f f e r e n t i a t e d or j u s t a few quadrate c e l l s ; annulus present; plants pseudo-paroicous H. styriacum 25. A l a r c e l l s i n f l a t e d , thin-walled, l e a f apex always acute; stem epidermis d i f f e r e n t i a t e d as an i l l - d e f i n e d hyalodermis..H. eugyrium 25. A l a r c e l l s quadrate to s l i g h t l y enlarged, incrassate; some l e a f a p i c i e s obtuse and denticulate; stem epidermis s i m i l a r to c o r t i c a l stem c e l l s , , H, subeugyrium 98 Hygrohypnum alpinum (Lindb.) Loesk., Hedwigia 43:194. 1904. Neotype: Norway, Gudbrandsdalenj B l y t t as Hypnum molle. (S-PA). Hypnum alpinum Schimp., Syn. ed. 2:777. 1876. hom. i l l e g . Amblystegium molle var. alpinum Lindb., Musci Scand, 33. 1879. Hypnum dilatatum var. alpinum (Lindb.) Ren., Rev. Bryol. 10:51, 1883. Hypnum molle var. alpinum (Lindb.) Boul., Muscin. Prance 24. 1884. Limnobium molle var. alpinum c (Lindb.) Vent, at Bott., A t t i . Soc. C r i t t . I t a l . ser. 2. fasc. 3:166. 1884. Hypnum dilatatum var. a-tpinum (Lindb.) Husn., Muse. G a l l . 413, 1894. Limnobium alpinum (Lindb.) Roth. Eur. Laubm. 2:642. 57f, 8. 1905. Pla£yphyllum alpinum (Lindb.) Loeske. Hedwigia 50:243. 1911. Names of taxa for which study material was unavailable and a v a i l a b l e l i t e r a t u r e was inadequate f o r evaluating the taxon. Hygrohypnum alpinum var. virescens Amann. F l . Mouss. Suisse 2:359. 1912. Names of taxa f o r which the l i t e r a t u r e was unavailable f or t h i s study, Amblystegium dilatatum var. alpinum (Lindb.) Adlerz. Bot. Not, 1883:7. 1883. Plants usually s o f t and p l i a b l e when moist or dry, le s s often somewhat s t i f f and b r i t t l e when dry, e s p e c i a l l y i n North American material, generally forming small loo s e l y woven patches or l e s s often l a r g e r more t i g h t l y woven mats, both of which e a s i l y fragment. Color v a r i a b l e , pale yellow, s i l t y yellow-brown, brownish-yellow-green or b r i g h t yellow-green, sometimes ex-h i b i t i n g a translucent sheen. Stems to about 5 cm long, l e a f y throughout? stems and stem leaves generally obscured within the mat or patch. Branching v a r i a b l e * , branches 1 - 2 (3.5) cm long, c h a r a c t e r i s t i c a l l y ascending to erect 99 i n one plane. Stem cross-section exposing 2 to 3 (4) rows of small, thick-walled, yellow or organe-^rown c o r t i c a l c e l l s ; medullary c e l l s l a r g e r , thin-walled, hyaline with l i t t l e evidence of wall thickening and d i s c o l o r a t i o n with age; c e n t r a l strand present, hyaline or brown-i s h . Rhizoids abundant, dark reddish-brown, smooJbh walled, a r i s i n g at the base of v e n t r a l stem leaves. Leaves v a r i a b l e ; c l o s e l y spaced or d i s t a n t , d i f f e r i n g l i t t l e from the wet to dry condition, though l e a f shrinkage i s r e a d i l y evident upon drying; c l o s e l y spaced leaves are l o o s e l y appressed-imbricate and e i t h e r e s s e n t i a l l y plane or ruffled-contorted; d i s t a n t leaves are spreading to erect-spreading and v a r i o u s l y contorted by marginal i n r o l l i n g or r u f f l i n g . Leaves (1) 1.3 - 1.7 (2) mm long X (0.9) 1.2 *•,].. 6 (1.7) mm wide; shape v a r i a b l e , usually oblong e l l i p t i c to o r b i c u l a r , but varying from ovate to transverse; margins usually e n t i r e , l e s s often f i n e l y serrate to s e r r u l a t e , e s p e c i a l l y i n the apex, varying among leaves on the same stem, us u a l l y plane throughout, o c c a s i o n a l l y s l i g h t l y recurved at the base. Leaves v a r i o u s l y plane or r u f f l e d or l e s s o f t e n weakly concave. Leaf base narrowly decurrent or transverse. Costa u s u a l l y double with slender arms, often very f a i n t , one or both arms may reach midleaf, r a r e l y slender and s i n g l e and/or forked with the main axis reaching s l i g h t l y above midleaf. Areolation v a r i a b l e ; median l e a f c e l l s short fusiform to l i n e a r f l e x -uose, moderately thin-walled, (25) 35 - 55 (75) um long X (4) 6 - 7 (9) um wide; a p i c a l c e l l s shortening gradually, v a r i o u s l y o v a l , quadrate or short fusiform; marginal l e a f c e l l s i n the upper h a l f of the l e a f l i t t l e d i f f e r e n t from the median c e l l s , u s ually 25 to 50 um long, r a r e l y longer; toward the l e a f base c e l l s v a r i o u s l y become longer or shorter i n length or s l i g h t l y wider or changing very l i t t l e from the median c e l l s ; basal c e l l s thicker 100 walled, hyaline or sometimes becoming yellowish or brown with age, p i t s few to none; a l a r c e l l s usually forming a well defined rectangular group of thin-walled, sometimes s l i g h t l y i n f l a t e d and/or excavated, i r r e g u l a r to rectangular c e l l s , normally hyaline, sometimes becoming brownish with age. Plants autoicous; p e r i g o n i a l leaves ovate, 0.5 to 0.8 mm long, eco-state, e n t i r e , except f o r 2 to 4 teeth at the sharply acute apex; outer p e r i c h a e t i a l leaves ovate to ovate lanceolate, ecostate, squarrose i n the upper h a l f ; inner p e r i c h a e t i a l leaves l i n e a r to l i n e a r - l a n c e o l a t e , up to 4 mm long, ecostate or f a i n t l y s i n g l e or double ecostate, 0, 2. or 4 deep p l i c a e ; margins of the middle and inner p e r i c h a e t i a l leaves charac-t e r i s t i c a l l y coarsely serrate at the apex with c e r t a i n c e l l s i n the apex coarsely p a p i l l o s e on the abaxial l e a f surface by ov e r r i d i n g d i s t a l endwalls. Seta 8 to 20 mm long, u s u a l l y 9 to 16 mm, color v a r i o u s l y yellowish-red, orangish-red or red, smooth, s t r a i g h t when wet, va r i o u s l y twisted when dry; capsule as per the genus. Outer peristome t y p i c a l f o r the genus; inner peristome teeth f i n e l y p a p i l l o s e , c i l i a absent or very rudimentary; spores dusky yellow or smoky grey, f i n e l y to coarsely p a p i l l o s e , 13 to 22 um i n diameter, usually 14 to 18 um. Hygrohypnum alpinum i s a well defined species and can be recognized r e a d i l y by i t s broadly ovate to o r b i c u l a r leaves which e x h i b i t a group of thin-walled, usually hyaline and ireegular to rectangular a l a r c e l l s . The long axis of the rectangular group of a l a r c e l l s i s p a r a l l e l to the l e a f margin (Pig. 27 g & h). Certain c e l l s i n the apex of the inner p e r i c h a e t i a l leaves are p a p i l l o s e on the abaxial surface by means of o v e r r i d i n g d i s t a l 101 endwalls (Pig. 27 a). This useful feature was f i r s t observed by Amann and Meylan (1912), but seems to have gone unnoticed since then. The species concepts of Hygrohypnum alpinum and H. dilatatum (Wils. 2 ex Schimp;) Loesk. have been intimately involved with a number of mis-conceptions of H. molle (Hedw.) Loesk. and H. alpestre (Hedw.) Loesk. Hedwig (1801) described Hypnum molle and H. alpestre based on the e a r l i e r concepts of Dickson (1790) and Swartz (1799) r e s p e c t i v e l y . Except f o r B r i d e l (1812, 1827), several subsequent workers treated Hypnum alpestre Sw. as synonymous with Hypnum molle Dicks. (Sprengel, 1827; De Notaris, 1838) or relegated Hypnum alpestre Sw, to v a r i e t a l status with Hypnum molle Dicks, (Hampe, 1837). Schimper (1853) p a r t i a l l y c l a r i f i e d the s i t u a t i o n , but a broad and somewhat mistaken concept of c e r t a i n species served only to cloud the issue. Like Hedwig, Schimper based h i s concept of Limnobium molle on that of Dickson. Schimper also observed that although Swartz (1799) accurately described Hypnum alpe s t r e , he represented the species with an i l l u s t r a t i o n that Schimper f e l t to be Hypnum molle sensu Dickson. This i s emphasized i n Schimper's treatment of Limnobium alpestre where he l i s t e d Hypnum alpestre as the basionym, but s p e c i f i c a l l y excluded Swartz* i l l u s -t r a t i o n , Tab. VI, r e f e r r i n g i t to Limnobium molle. Obviously, Schimper noted that Hypnum Stereddon a l p e s t r i s B r i d , from Bryolbgia Universa II i s synonymous with Hypnum molle Dicks, and s i m i l a r l y Hypnum Stereodon m o l l i s B r i d . was synonymous with Hypnum alpestre Sw. However, B r i d e l (1827) c l e a r l y 2 Evidence to be presented l a t e r has established that the name Hypnum duriu-sculum De Not, has p r i o r i t y over Hypnum dilatatum Wils. i n Schimp, However, for the sake of c l a r i t y Hypnum dilatatum w i l l be employed i n the present d i s -cussion. 102 indicated that H. S_. a l p e s t r i s was based on Hypnum alpestre Sw, and H. S_. m o l l i s was based on Hypnum molle Dicks. The concept of Limnobium molle Schimp* seems to have been a very broad one, Schimper (1853) i l l u s t r a t e d the species with two plat e s : Tab. I l l , F i g . 1 - 14, pg. 576 and Tab. IV, F i g . 2 - 6 , pg. 577. Schimper (1860) extracted and described Hypnum alpinum Schimp. and H, dilatatum Wils. i n Schimp. from the 1853 concept of Limnobium molle. To i l l u s t r a t e these two new taxa Schimper c i t e d Tab. I l l , F i g . 1 - 14. pg. 576 to represent Hypnum  alpinum and Tab, IV, F i g . 2 - 6, pg. 577 to represent Hypnum dilatatum. Fufclfcher, Sfchimper (1860) c i t e d no i l l u s t r a t i o n f o r h i s more r e s t r i c t e d treatment of Hypnum molle, but c l e a r l y based i t on Dickson's concept. An examination o f the few a v a i l a b l e Schimper specimens in d i c a t e s that he held a sound concept of Hypnum molle, H. dilatatum, H, alpinum and H. alpe s t r e . I t i s , therefore, remarkable that: 1. the i l l u s t r a t i o n c i t e d to represent Limnobium alpestre i n Bryologia Europaea and redesignated i n Syn, ed I i s c l e a r l y Hygrohypnum molle (Hedw.) Loesk. and, 2. that i n Syn. ed. I, he c l e a r l y ascribes the Swactz i l l u s t r a t i o n of Hypnum alpestre to Hypnum  alpinum Schimp. As presently understood Hygrohypnum molle (Hedw.) Loesk., H. dilatatum (Wils. i n Schimp.) Loesk., H. alpinum (Lindb.) Loesk, and H. alpestre (Hedw,) Loesk. are very c l e a r l y defined species. Of the i l l u s t r a t i o n s i n Bryologia  Europaea, Tab. I I I . F i g . 1 - 14, pg. 576 ace r e f e r a b l e to Hygrohypnum alpinum, Tab. IV. F i g . 2 - 6 , pg, 577 are r e f e r a b l e to H, dilatatum and Tab. IV, F i g , 1, l b and 7 - 21, pg. 577 are r e f e r a b l e to H, molle. I t i s worth noting that Hedwig's (1801) Tab. LXIV. F i g . 2 for Hypnum  alpestre i s misleading. I t erroneously shows a s i n g l e costa i n the leaves. The costa of Hygrohypnum alpestre i s usually short and double or long and 103 double. S i m i l a r l y , Tab. IV, P i g . 7, pg. 577 from Bryologia Europaea shows a f a l c a t e l e a f with a s i n g l e costa, a character combination that i s unknown i n Hygrohypnum molle. As l a t e i s 1927 Monkemeyer erroneously represented Hygrohypnum d i l a - tatum with an i l l u s t r a t i o n obviously of H. molle (Fig. 168 b). The sim-i l a r i t y of H. alpinum and H. dilatatum l e d Lawton (1971) to employ a l e a f of H. alpinum to represent H. dilatatum ^Plate 156, F i g . 1). As there has been considerable confusion over several taxa i n the ^Hygrohypnum molle complex", so too has there been confusion concerning the nomenclatorial status of Hygrohypnum alpinum. Schimper (1876) described Hypnum alpinum Schimp. as a segregate from Limnobium molle Schimp. Unfor-tunately, Hypnum alpinum Schimp. i s a l a t e r homojiym of Hypnum alpinum (With.) Web. et Mohr. The f i r s t name to be v a l i d l y and l e g a l l y applied to Schimper's taxon was Amblystegium molle var. alpinum i n Lindberg (1879). Lindberg c l e a r l y i ndicated that the v a r i e t y was based on Schimper's o r i g i n a l concept. Schimp-er (1876) based the species on 5 c i t e d specimens, but designated no holotype. Of the f i v e specimens two are important. Schimper c i t e d a B l y t t specimen from the Norwegian Dovrefjeld and a specimen c o l l e c t e d by Thedenius from Nedalen i n the Harjedalem region of Sweden. That Nedalen i s now a part of NSrway i s of l i t t l e import. These two specimens have hot been seen. However, a B l y t t specimen c a l l e d Hypnum molle from Gudbrandsdalen, Norway, a s i t e not f a r from the Dovrefjeld, and a Thedenius specimen c a l l e d Hypnum  dilatatum from Tannas i n the Harjedalen d i s t r i c t of Sweden and again a s i t e not f a r from Hedalen, are present at S-PA. Both of these specimens are v a l i d examples of Hygrohypnum alpinum. The B l y t t specimen i s i n the better condition of the two. In the absence of any proven Schimper material of Hygrohypnum  alpinum, the B l y t t specimen i s selected as the neotype. 104 Hygrohypnum alpinum e x h i b i t s some v a r i a t i o n i n l e a f shape, costa structure, the nature of the l e a f margin and the a t t i t u d e of the leaves upon the stem. Leaf shape va r i e s from broadly ovate to o r b i c u l a r (Fig. 26 a - e ) . The l e a f apex may be broadly acute or rounded with a small, abrupt apiculus (Fig. 26 a s~e), The costa i s usually slender and double, but r a r e l y one may encounter a slender, si n g l e and/or forked costa reaching mid-leaf (Fig. 26 a - e). Schimper's (1876) d e s c r i p t i o n noted the f i n e l y s e r r u l a t e margin at the l e a f apex. The present study has shown the margin to the l e a f apex to vary from e n t i r e to f i n e l y s e r r u l a t e between leaves on the same or d i f f e r e n t plants. One of the most remarkable features of H. alpinum i s the d i s p o s i t i o n of i t s leaves along the stems. V i r t u a l l y a l l the leaves of North American specimens and a s i g n i f i c a n t number of European specimens e x h i b i t leaves that are convolute or r u f f l e d p a r a l l e l to t h e i r l o n g i t u d i n a l axis (Fig. 26 f, g & h). Other European specimens e x h i b i t leaves that are e s s e n t i a l l y plane or s l i g h t l y concave (Fig, 26 Hygrohypnum alpinum i s most e a s i l y confused with H. duriusculum. The following table of characters w i l l help to separate them. i & j ) . H. alpinum H. duriusculum Ala r c e l l s thin-walled, more or l e s s rectangular, and hyaline. A l a r c e l l s thick-walled, quadrate to i r r e g u l a r , usually discolored. A p i c a l p e r i c h a e t i a l l e a f c e l l s p a p i l l o s e by a n t e r i o r l y over-r i d i n g end walls. P e r i c h a e t i a l l e a f c e l l s smooth. Endostomial c i l i a absent or very rudimentary. One or two well to poorly developed c i l i a between the endostomial teeth. Stem branches usually l e s s than 2 cm long, more or l e s s ascends ing to erect. Stem branches of v a r i a b l e length, us u a l l y prostrate or ascending. 105 -Older stems generally r e t a i n - Older stems generally denuded ing t h e i r leaves. of leaves. In Europe Hygrohypnum alpinum and H. duriusculum can be f a i r l y e a s i l y separated by f i e l d observable characters. Hygrohypnum alpinum normally forms s o f t , e a s i l y fragmenting patches of t i g h t l y woven, s t o l -oniferous stems, from which a r i s e numerous short, ascending to erect branches. The stoloniferous stems are generally f o l i o s e throughout and densely clothed i n r h i z o i d s v e n t r a l l y . Hygrohypnum duriusculum i s r i g i d to the touch and the prostrate, i r r e g u l a r l y branched stems are r e g u l a r l y denuded i n the older extremities. Rhizoids are sparse or absent. Branches of i r r e g u l a r p o s i t i o n and v a r i a b l e length usually l i e p a r a l l e l to the stem and are prostrate to s l i g h t l y ascending at the t i p s . The patches or t u f t s do not fragment e a s i l y . In western North America one must i n i t i a l l y r e l y ap microscopic characters to separate H. alpinum and H. duriusculum. In t h i s region H. duriusculum often assumes a habit s i m i l a r to that of H. alpinum, i . e . densely f o l i o s e , and densely r h i z o i d a l s t oloniferous stems which bear numerous short, erect or ascending branches. With increased f i e l d ex-perience one can employ the r u f f l e d appearance of the leaves H. alpinum (Fig. 26 g & h) to separate i t from H, duriusculum whose leaves are generally l e s s crowded and more symmetrical, plano-concave-(Fig. 29 c ) , My own f i e l d experience with Hygrohypnumalpinum i n Western North America has been confined to southern B r i t i s h Columbia. In that region the species occurs e x c l u s i v e l y on large boulders on the banks of or i n the middle of small, s w i f t l y running mountain streams. The only time that t h i s species occurs i n a submerged s i t u a t i o n f o r any length of time i s during spring runoff. Otherwise, i t occurs on emergent rocks that are subjected to spray from turbulent water. 106 F i g . 26 a - j . V a r i a t i o n i n the l e a f shape and the habit of the shoots of Hygrohypnum alpinum. a - e. V a r i a t i o n i n f o l i a g e leaves. J f . A moist shoot of a specimen with r u f f l e d leaves from Western North America. g - h. Comparison between the moist (g) and dry ; (h) shoot of a r u f f l e d leafed specimen from western North America. i - j . Comparison between the moist (i) and dry (j) shoot of a plane to concave leafed specimen from Europe and North America. Scale: a - e? I 1mm I f - j ; Each stem i s approximately 1 cm long. 107 1 0 8 F i g . 27 a - h . C e l l u l a r d e t a i l of the p e r i c h a e t i a l and f o l i a g e leaves of Hygrohypnum alpinum. a. P e r i c h a e t i a l l e a f apex, b - c. Foliage l e a f a p i c i e s . d. Median c e l l s of f o l i a g e leaves, e - f . Marginal c e l l s of f o l i a g e leaves, g - h . A l a r c e l l s of f o l i a g e leaves. Scale: a j 1 100 um I b - c, g - h ; . I , 100"m I d - f . I -• 100um I —-110 F i g . 28. Hygrohypnum alpinum I l l E x s i c c a t i Examined Macoun, Canadian Musci # 357 as H, dilatatum. (TRTC) # 396 as !H. alpestre, but i n part H. luridum. (USA, NY, MO) # 900 as H, dilatatum. (USA) Canidian Mosses, # 490 as H. dilatatum. (USA, NY) Grout, North American Musci Pleurocarpi, # 427 as H. dilatatum. (MIN, MO, NY, TENN, UC, USA) Bauer, Musci europ. et amer. a x s i c c a t i , # 2089. (BRNM, NY S-PA) Rabenhorst, Bryotheca europaea, # 1348. (NY, S-PA) Husnot, Musci G a l l i a e , # 593 as H. palustre var. julaceum. (S-PA) Verdoorn, Musci S e l e c t i et C r i t i c i , s e r i e s VI, # 270. (MICH, NY, LE, TENN) Selected Specimens Examined Canada B r i t i s h Columbia G a r i b a l d i P r o v i n c i a l Park, Sentinel G l a c i e r Area? Schofield 32953 as H. al p e s t r e . (CAMN, DUKE, TENN)-• North Vancouver, Lynn Canyon; Schofield 35292 as H. dilatatum. (HBP) <i?C* Caribou D i s t r i c t , end of Long Lake; Boas 688 as H. dilatatum. (CAN, UBC) G l a c i e r ; Macoun as H. dilatatum IN Canadian Musci # 900 (USA) Kamloops Lake D i s t r i c t , Skuian Creek; Brinkman 259 as H. d i i a - . , tatum. (CAN, MICH) Lake Lindeman; Williams 6 May 1896 as H. dilatatum. (NY) Salmo, Sheep Creek; Jamieson 5551. (UBC) United States Alaska St. ?acrous Bay; Howell 18 Aug 1895 as H. dilatatum i n • Howell's Alaska P a c i f i c Coast Plants # 1818. (NY) Short Bay; Howell 8 Aug 1895 as H. molle. (MIN) Washington Cascades Mtns, Copper Creek; A l l e n , June 1905 as H. dilatatum i n North American Musci Pleurocarpi # 427. (MICH, NY, TENN, WTU, MO, UC, USA) Snohomish Co., Monte C r i s t o ; S c h o f i e l d 20085 as H. dilatatum . (CAN, S-PA) Clallam Co, Olympic National Park, Olympic Hotsprings; S v i l h a 758 as H. dilatatum, (WTU; F) Mount Rainier Region, Paradise V a l l e y ; Frye 11 Aug 1904 as H. dilatatum. (WTU) Chelan Co., Transen Creek; Sharp 2112. (TENN) Idaho Bonner Co., P r e i s t Lake; Ireland 8565 as H. dilatatum. (ALTA, UBC) Lemhi Indian Reservation, M i l l Creek; Henderson 3979 as H. dilatatum. (USA) V Montana G l a c i e r National Park, Lake MacDonald; Standley 18388 as H. alpinum. (USA) 112 Missoula Co. Rattlesnake Campground; Sharp & Clebsch M-16. (TENN) B e l t Mountains; Williams 19 Sept 1891 as H. arcticum, admixture of H. b e s t i i and H. dilatatum. (MIN) C a l i f o r n i a Siskiyou Co., Duck Lake Creek; Norris 23300 as H. dilatatum. (HSC) France Dep. de I'Isere, V a l l o n des Etages; Culmann 2 Sept 1927 i n Musci europ. et amer. e x s i c c a t i # 2089. (S-PA, TENN, NY, BRNM) Haute Savoie, Mt. Blanc; Payot, i n Musci G a l l i a e # 593. (S-PA) Switzerland V a l a i s , Mattmark; Nicholson & Dixon 7 J u l y 1913. (BM) Berner, Oberlander, Handegg; Culmann Sept 1911 i n Musci S e l e c t ! et C r i t i c i , s e r i e s VI, # 270. (MICH, NY, TENN) Tessin, T i c i n o , Compolungopass; Traumann 8 June 1908, (S-PA) U r i , A l p e t t i ; Culmann 7 Aug 1882. (S-PA) Au s t r i a T i r o l , Otzaler Alpen; Berner J u l y 1931. (S-PA) Vorarlberg, Arlberg; Eggler. (S-PA),; Salzburg, Kresmuler; Loeske 2 Aug 1903. (S-PA) Karnten, Malta; B r e i d l e r 1885. (S-PA) I t a l y Macuguaga, Val Anyasca; Nicholson & Dixon 10 J u l y 1913. (BM) Iceland N. V, Dynjauvi; Hesselbo 26 June 1912. (NY) Norway Opdal, Driva; Kaurin Okt 1881. (S-PA) Gausta; JMderholm J u l y 1895. (S-PA) Hordaland, Hardanger; K o t i l a i n e n 2 Sept 1931. (S-PA) Gudbrandsdalen; B l y t t as H. molle. NEOTYPE, (S-PA) tEroms, Lyngen, Kjosen; T. Ulsinen 20 Sept 1968. (LE) Sweden Harjedalen, Storsjo; Thedenius J u l y 1842. (S-PA) Jamtland, Frostvikens; Nyman 6 Aug 1947. (S-PA) Asele Lappmark, M a r s f j a l l e t , J i l k e l m i n i a r Hulphers 14 June 1943. (S-PA) Lycksele Lappmark, S t o r f j a l l e t back v i d V a l l i n t j a k k o ; Normann 15 Aug 1945. (S-PA) P i t e Lappmark, Arjeplogs; Moller 30 J u l y 1918. (S-PA) Lule Lappmark, Kamajokk; NymanaAug 1893. (S-PA) Torne Lappmark, Karevaggejokk; Nicholson & Dixon 26 Aug 1907. (BM) 113 Hygrohypnum duriusculum (De Not.) Jamieson nov. comb. Lectotype: Erbar. C r i t t o g . I t a l , ser. I I , no. 204. (<§) Limnobium duriusculum De Not., Erbar. C r i t t . I t a l . ser. I I , no. 204. 1869. Hypnum dilatatum Wils. i n Schimp. Syn. Ed. 2. 776. 1876. ( Amblystegium dilatatum (Wils.) Lindb. Musci Scand. 33. 1879. Limnobium dilatatum (Wils. i n Schimp.) Vent, et Bott., A t t i . Soc. C r i t t . I t a l , ser. 2, 3:166. 1884. Hypnum molle var. dilatatum (Wils. i n Schimp.) Boul. Muscin. France. 24. 1884. Hypnum pseudo-arcticum Kindb., B u l l . Torrey Bot. Club 17(11):280. 1890 Hypnum c i r c u l i f o l i u m Cs»: M. & Kindb. i n Macoun, Cat. Canad. PI. 6:242. 1892. C a l l i e r g o n dilatatum (Wils. i n Schimp.) Kindb,, Canad. Rec. S c i . 6:72. 1894. Ca l l i e r g o n c i r c u l i f o l i u m (C. M. & Kindb, i n Macoun) Kindb., Canad, Rec. S c i . 6:72. 1894. Limnobium pseudo-arcticum (Kindb.) Kindb., Canad, Rec. S c i . 6:74. 1894. Hypnum molle ssp. dilatatum (Wils. i n Schimp.) Dix., Stud. Handb. B r i t . Mosses. 483. 1896. Ca l l i e r g o n pseudo-arcticum (Kindb.) Kindb., Eur. N, Am, Bryin, 1:85. 1897. Hypnum eugyrium var. dilatatum (Wils. i n Schimp.) Grout, Mosses Handls. Mies. 345, 1903. Hypnum dilatatum var. duriusculum (De Not.) Limpr., Laubm. Deutsch. 3:353. 1904. 11.4 Limnobium dilatatum var. duriusculum (De Not.) Roth, Eur. Laub. 2:645. 1905, Hygrohypnum pseudo-arcticum (Kindb.) Broth,, Nat. P f l . 1(3):1040, 1909. Hygrohypnum c i r c u l i f o l i u m (C, M. & Kindb. i n Macoun) Broth,, Nat. P f l . 1(3):1039. 1909. Hygrohypnum dilatatum var. duriusculum (De Not.) Amann, F l . Mouss. Suisse 2:361. 1912. Hygrohypnum cordifolium Okam., J , C o l l . Imp. Univ. Tokyo 36:30. 14. 1915. Names of taxa for which neither the appropriate l i t e r a t u r e nor any specimens were a v a i l a b l e during t h i s study. Hygrohypnum dilatatum var. callineurum-Amann, Bui. Soc. Vaudoise Sc. Nat. 53:123. 1920. Plants usually coarse and s t i f f to the touch, r a r e l y s o f t and f l e x i b l e , forming lo o s e l y to t i g h t l y woven mats or patches, r a r e l y deep cushions or t u f t s . Color v a r i a b l e , b r i g h t yellow-green with rusty mottling, d u l l o l i v e -green with rusty mottling, d i r t y yellow to yellow-brown with or without rusty mottling, a l l colors grading i n t o one another at various times. Stems (1) 2 - 7 (9) cm long, f o l i o s e throughout or denuded from the base to more than h a l f the length of the stem. Branching i r r e g u l a r , u sually ascending from procumbent stems; often the only l e a f y part of the plant, but sometimes denuded at the base. Stem cross-sections revealing 3 to 4 rows of small, thick-walled yellowish to reddish-brown c o r t i c a l c e l l s ; medullary c e l l s l a rger, thin-walled, sometimes becoming thi c k e r walled and discolored with age; c e n t r a l strand well developed, often d i s c o l o r e d . Rhizoids v a r i a b l e , infrequent or densely c l o t h i n g the v e n t r a l surface of prostrate stems, a r i s i n g 115 from the bases of v e n t r a l stem or branch leaves. Leaves v a r i a b l e , c l o s e l y spaced to widely d i s t i n c t , d i f f e r i n g i n appearance within and between the wet and dry conditions! Wet condition, leaves appressed imbricate or spreading and somewhat contorted, some c l o s e l y spaced appressed imbricate leaves are often secund, other c l o s e l y spaced leaves are spreading to erect spreading and v a r i o u s l y contorted, while s t i l l other c l o s e l y spaced leaves simply appressed imbricate; widely spaced leaves when wet, v a r i o u s l y l o o s e l y appressed imbricate or spreading: Upon drying, a l l leaves whether loosely spaced or d i s t a n t , appressed-imbricate, secund or spreading, undergo varying degrees of shrinkage i n width, spreading and contortion; the contortion may involve twisting, u s u a l l y toward the stem and to the l e f t or i n r o l l i n g on the margins with concomitant twisting., Leaves may vary from c l o s e l y to widely spaced from one region of the stem to another; Leaves s t r a i g h t when wet, contorted when dry, sometimes appearing f a l c a t e from the shrinkage, never t r u l y f a l c a t e when moist. Leaves (0.7) 1.25 - 1.8 (2.3) mm long X (0.6) 1.0 - 1 . 4 (1.8) mm wide; shape usually o b l o n g - e l l i p t i c to broadly ovate, l e s s often o r b i c u l a r or ovate; margins usually e n t i r e , often uneven or undulating, r a r e l y c l e a r l y s e r r u l a t e , often narrowly reflexed i n the a l a r region; plane or shallowly concave; apex va r i o u s l y acute, obtuse, obtuse with a^ small apiculus or rounded; l e a f base often narrdwly decurrent at the point of i n s e r t i o n and sometimes c l a s p i n g the stem with a narrow c o l l a r ; costa v a r i a b l e , usually short and double with slender forks reaching to midleaf, often short and double and very f a i n t , short and s i n g l e , or s i n g l e and/or b i - or t r i f u r c a t e reaching well above the middle. Areolatiqn exteemely v a r i a b l e ; Median l e a f c e l l s short fusiform to long l i n e a r flexuose, r a r e l y long rhombic, v a r i o u s l y t h i n to moderately t h i c k -116 walled? (26) 45 - 70 (104) um long X (3) 5 - 6 (8) um wide, c e l l dimen-sions v a r i a b l e between leaves on the same stem and often d i f f e r i n g from one side to the other of the same leaf? c e l l s shortening gradually toward the apex, a p i c a l c e l l s shape v a r i a b l e , fusiform, short rhombic, rounded rectangular to rounded quadrate? marginal c e l l s usually shorter than adja-cent laminal c e l l s , 25 to 50 um long, a few i s o l a t e d c e l l s may r a r e l y ex-ceed 60 um, e s p e c i a l l y i n large European specimens; c e l l s u s u a l l y increasing i n length, widfeh and w a l l thickness toward the l e a f base, shape d i f f e r i n g l i t t l e from median c e l l s ? basal c e l l s thick-walled, p i t s few to none, be-coming dis c o l o r e d with age, yellowish to reddish-brown d i s c o l o r a t i o n sometimes creat i n g a weak sunburst e f f e c t across the base? a l a r c e l l s forming a well defined group of thick-walled, quadrate to short rectangular c e l l s , or i r r e g u l a r , plane to deeply excasrated, reaching 3 to 5 rows from the margin and 4 to 5 c e l l s up the margin from the l e a f base. Plants autoicous? p e r i g o n i a l leaves ovate lanceolate, 0.6 to 0,75 mm long, ecostate, e n t i r e or s l i g h t l y serrate at the apex, deeply concave; outer p e r i c h a e t i a l leaves ovate lanceolate, weakly eostate to ecostate, squarrose from above the middle? inner p e r i c h a e t i a l leaves l i n e a r lanceolate, up to 3 mm long, ecostate or with a very f a i n t , long s i n g l e or forked costa reach-ing to 3/4 of the l e a f length, 2 to 4 long p l i c a e , margins e n t i r e or sometimes s l i g h t l y serrate i n the apex, l e a f c e l l s a l l smooth. Seta 9 to 27 mm long, usually 12 to 20, co l o r v a r i o u s l y yellowish-red, red or maroon, smooth, s t r a i g h t when wet, v a r i o u s l y twisted when dry. Capsule t y p i c a l f o r the genus, annulus o f 2 to 3 rows of deciduous c e l l s . Peristome c h a r a c t e r i s t i c of the genus; endostome usually with J to 3 well defined c i l i a , sometimes rudimentary; spores smoky brown, f i n e l y p a p i l l o s e , (11) 15 - 19 (23) um i n diameter.^ 117 Hygrohypnum duriusculum i s a highly v a r i a b l e species and i s only s l i g h t l y l e s s complex than H. luraldum. Under the microscope, the species can be recognized best by i t s u s u a l l y o b l o n g - e l l i p t i c to broadly ovate leaves (Fig. 30 a - c) and the well defined group of thick-walled, u s u a l l y d i s c o l o r e d , quadrate, short rectangular c*r s l i g h t l y i r r e g u l a r a l a r c e l l s (Fig. 31 c, e - h). Coarseness and r i g i d i t y of habit and d e f o l i a t i o n of the older parts of the stems have long been used as f i e l d c r i t e r i a c h a r a c t e r i z i n g H. dur-iusculum. Though useful characters, they should be used with d i s c r e t i o n . C ertain specimens from the Austrian and Swiss Alps and the Norwegian mountains are very s o f t to the touch and could be confused with H. molle. In North America H. duriusculum, H. b e s t i i and H, s m i t h i i are coarse, s t i f f and have d e f o l i a t e d older stems. Furthermore, H_. duriusculum i s sometimes f o l i o s e throughout. The a t t i t u d e of the leaves on the stems allows one to recognize several growth forms, which often intergrade. These forms can be roughly correlated geographically. Hygrohypnum duriusculum most commonly forms low appressed mats or patches on rocks i n streams. In Europe and Eastern North America i t i s common f o r the leaves to be rather d i s t a n t along the stems (Fig. 29 a - d). When dry, the leaves of European specimens are conspicuously shrunken (Fig. 29 f ) , In the shrunken condition the leaves become v a r i o u s l y contorted, twisting i n various d i r e c t i o n s or spreading-squarrose. There appears to be no r e g u l a r i t y i n the contortion or spreading of the leaves. Leaf shrinkage upon drying sometimes give the suggestion of f a l c a t i o n , but t h i s i s l o s t upon rewetting. Leaf shrinkage i s l e s s pronounced i n Eastern North American material with d i s t a n t leaves. The pattern of contortion i s more regular. The dry leaves of specimens from Eastern North America are predominantly widely to erect -118 spreading, sometimes almost squarrose (Fig. 29 d). The leaves are furthe r contorted; e i t h e r twisted upon themselves or with t h e i r margins i n r o l l e d to form a channel and then twisted. Plants of t h i s form are most common i n the New England States, New York, the northern Appalachian mountains, Quebec and the Maritime provinces. Some specimens from Europe and Eastern North America bearing d i s t a n t leaves have the leaves l o o s e l y appressed imbricated. Their leaves are not so obviously shrunken. Another form common to Europe and Eastern North America, which may also reach into Western North America bears i t s .leaves rather close to-gether (Fig. 30 h). The leaves are not as conspicuously Shrunken and are loo s e l y apressed imbricate. Though t h i i form and the previous ones are sometimes remarkable d i s t i n c t , they do intergrade. This would imply that the forms are responses to some environmental phenomenon. Certain specimens can be found i n both Europe and North America which bear d i s t i n c t , more or le s s spreading leaves i n the lower part of the stem and more or l e s s c l o s e l y spaced appressed imbricate leaves at or near the stem apex or v i c e versa. A v a r i a t i o n of these plants with c l o s e l y spaced, loo s e l y appressed imbricate leaves, occurring e r r a t i c a l l y throughout the e n t i r e range of the species, i s one i n which the appressed imbricate leaves are often swept to one side of the stem cre a t i n g a secund appearance (Fig. 29 g S h). Certain European material of t h i s type has leaves that are s l i g h t l y more shrunken than those from Scandinavia or North America. This form, too, grades imperceptibly into other forms. In Western North America habit v a r i a t i o n e xhibits another pattern. The plants tend to form low, prostrate, densely woven mats of denuded or f o l i o s e stems bearing numerous ascending to erect, densely f o l i a t e d braches, which seldom exceed 1.5 cm i n length. Leaves i n t h i s form are usually d i s t a n t , 119 though they may vary from spreading contorted or secund. Growth forms i n Europe and North America that have widely spaced leaves u s u a l l y form loosely woven mats. In these plants i t i s often d i f f i c u l t to d i s t i n g u i s h branches from stems as both may be l e a f y . More impofctant i s the f a c t that the stems or branches are usually much longer than the 1.5 cm long branches of Western North American material. I f herbarium material can be taken as a measure of the habit d i v e r s i t y and the q u a l i t y of growth reached i n d i f f e r e n t l o c a l i t i e s and under d i f f e r e n t environmental conditions, then i t can be said that Hygrohypnum duriusculum reaches i t s most favorable growth p o t e n t i a l i n the high Alps of Austri a , Switzerland and adjacent I t a l y , Numerous specimens c o l l e c t e d by B r e i d l e r , Glowacki, Ganders et a l , i n the l a s t century show that, i n the aforementioned areas H. duriusculum forms large, thick cushions or almost t u r f - l i k e mats. Only r a r e l y does material from other areas approach the s i z e attained i n the high Alps. In North America and extra-alpine areas of Europe, Hygrohypnum duriusculum occurs more frequently as the well known, e a s i l y fragmenting mat or patch of s t i f f , naked stems bearing many fewer l e a f y branches. Certain depauperate or otherwise anomalous specimens from Eastern North America have been confused with other taxa or are puzzling. Three specimens c o l l e c t e d by A, J . Sharp from Laurel F a l l s and Roaring Fork i n the Great Smokey Mountains National Park of Tennessee have been c i t e d i n the past as evidence for the presence of H. cochlearifolium i n eastern North America. One of these specimens was i s s u e d as Hygrohypnum coc h l e a r i f o l i u m by A. J . Grout i n # 59 of North American Musci Pleurcarpi Supplement, Comparison of these specimens with H, duriusculum have shown them to be depauperate forms o f duriusculum . Ovate e l l i p t i c to o r b i c u l a r leaves are borne appressed-120 imbricate on erect branches a r i s i n g from fragmented, denuded stems. This compares favorably with s i m i l a r , though more robust specimens from f a r t h e r north. The a l a r : c e l l s , though very poorly d i f f e r e n t i a t e d , are those of Ii. duriusculum. Another A. J . Sharp specimen from Mica Bay i n the Algoma d i s t r i c t , Northern Ontario i s also remarkable. I t s crowded, o r b i c u l a r , almost plane leaves borne on short stems and branches bear a s t r i k i n g resem-blance to Hygrohypnum alpinum. However, the presence of well d i f f e r e n -t i a t e d quadrate, short rectangular, thick-walled a l a r c e l l s reveals i t to be H. duriusculum. C r i t i c a l study of approximately 300 specimens reveals that an oblong-e l l i p t i c to o r b i c u l a r l e a f i s the usual case. S t i l l , some v a r i a t i o n occurs between leaves on the same plant. In broadly ovate leaves the greatest width i s reached at a point somewhere between the lower quarter and the lower t h i r d of the l e a f . As the l e a f shape approaches o r b i c u l a r the widest point r i s e s to the middle of the l e a f . The notable v a r i a t i o n occurs when the widest part r i s e s above the middle of the l e a f to produce a s l i g h t l y obovate condition (Fig. 30 e). Leaves of such shape are not common. Ovate or o v a t e - e l l i p t i c l e a f shapes do occur r a r e l y i n plants that are otherwise depauperate. The shape of the apex r e a d i l y v a r i e s from broadly acute , obtuse, rounded or obtuse or rounded with a small apiculus. V i r t u a l l y a l l published descriptions of Hygrohypnum duriusculum make reference to the weak s e r r u l a t i o n of the a p i c a l l e a f margin. Tab, I I I , 576 from Bryol. eur. was c l e a r l y r e f e r r e d to Hypnum alpinum by Schimper (1876). However, t h i s plate has been frequently and erroneously re f e r r e d 12-1 to H. duriusculum. Figure 4 a of Tab. I l l no doubt has been responsible f o r the notion that H. duriusculum has a s e r r u l a t e apex. Study of more than 200 European specimens of v a l i d H. duriusculum has shown that a se r r u l a t e margin i s of infrequent occurrence. Quite often, however, the outer wall of the marginal c e l l s seems p a r t i a l l y resorbed, thus g i v i n g the i l l u s i o n of teeth. The are o l a t i o n of Hygrohypnum duriusculum i s highly v a r i a b l e . The lengths of median l e a f c e l l s vary from 25 to 100 um. A few European spec-imens have large leaves with median l e a f c e l l s uniformly i n the 60 to 100 um range. There i s no c o r r e l a t i o n between l e a f s i z e and median l e a f c e l l length. Median l e a f c e l l s may vary i n length from one side of the l e a f to the other. Zdenk Pilous erected the name Hygrohypnum dilatatum f a bulbosa and d i s -t r i b u t e d two specimens of t h i s form as numbers 429 and 485 of h i s musci cecho-s l o v e n i c i e x s i c c a t i . He based the form on the presence of small bulbs found at the a p i c i e s of various stems and branches. The plants are l i t t l e more than entagled, denuded stems. Examination of the bulbs has shown them to be c l u s t e r s of c l o s e l y spaced, t i g h t l y imbricated leaves that have enveloped the stem or branch: a p i c i e s . The bulbs, l i k e the stems, are dark brown i n c o l o r . The bulbs are probably the r e s u l t of a p i c a l growth under severe environmental conditions and, as such, are of no taxonomic value. Kindberg described Hypnum pseudo-arcticum i n Macoun (1890) and d i s -tinguished i t from H. arcticum by i t s crenulate l e a f margin and the short double costa. Grout (1930), however, stated that the plant had abruptly acuminate apex and treated the plant as synonymous with Hygrohypnum luridum. An examination of the holotype XS-PA) reveals that Grout evaluated an admixed fragment of Hygrohypnum luridum while Kindberg, himself, described a small fragment of what i s rather t y p i c a l Hygrohypnum duriusculum from Western North 122 America. An examination of the holotype (NICH) of Hygrohypnum cordifolium Okara. reveals that i t i s i d e n t i c a l with Hygrohypnum duriusculum (De Not,) Jamieson. The Okamura specimen agrees with H, duriusculum i n terms of l e a f shape, a l a r d i f f e r e n t i a t i o n and o v e r a l l appearance. In 1869 De Notaris d i s t r i b u t e d Limnobium duriusculum as the exsiccatum Erbar. Crittogam, I t a l . ser. I I , no. 204. The l a b e l of t h i s exsiccatum bears a complete L a t i n d e s c r i p t i o n and a reference to Lago Maggiore., I t a l y as the type l o c a l i t y . Two specimens (at G and UC) of t h i s important e x s i -c c a t i have been a v a i l a b l e f o r study. Index Muscorum, volume 5 (1969) indicated that the De Notaris name i s a nomen nudum. A r t i c l e 31 of the Seatt l e e d i t i o n o f the Rules of Nomenclature implies that names with accom-panying descriptions borne on exsiccata l a b e l s before 1 January 1953 are va published. Consequently, Limnobium duriiusculum De Not, i s a v a l i d name. The s i g n i f i c a n c e of t h i s name i s c r u c i a l f o r Limnobium duriusculum De Not. i s unquestionably the same organism as Hypnum dilatatum Schimp. Hypnum  dilatatum was described by Schimper (1876) based on a manuscript submitted to him by William Wilson. Therefore, Limnobium duriusculum has p r i o r i t y o v e r Hyp""1" dilatatum and beetaues the l e g a l basionym of Hygrohypnum duriu-sculum (De Not.) Jamieson. The specimen of the De Notaris exsiccatum at G i s designated as the lectotype. 123 F i g . 29 a - h. V a r i a t i o n i n the habit of l e a f y shoots of Hygrohypnum  duriusculum and comparisons between the wet and dry conditions i n the shoots. Each p a i r of fi g u r e s , a - b , c - d , e - f , and g - h represents the comparison between the wet and dry condition i n four d i f f e r e n t shoots. Figures a, c, e, and g i l l u s t r a t e the moist condition i n each ehoot. Scale: Each shoot i s approximately 1 cm long. 124 125 P i g . 30 a - h. V a r i a t i o n i n f o l i a g e l e a f shape, length of marginal leaf c e l l s and the habit of l e a f y shoots of Hygrohypnum duriusculum. a - e. Foliage leaves f - g. Marginal l e a f c e l l s h. Leafy shoot Scale: a - e. I 1mm | f - g. I • 100um | h. this shoot i s approximately 1 cm long 126 127 Pig. 31 a - h. V a r i a t i o n i n the apices and c e l l u l a r d e t a i l of the leaves of Hygrohypnum duriusculum. a - b. -Leaf a p i c i e s c, e - h. A l a r c e l l s d. Median l e a f c e l l s Scale: , a - c, e - h. I l M u m _ J d. I ' 100um I \ 128 129 F i g . 32. Hygrohypnum duriusculum 130 E x s i c c a t i Examined Austin, Musci Appalachian! # 436 as JL molle. (MICH, NY, USA) Grout, Hand-lens Mosses # 72. (MIN, NY) North American Musci P e r f e c t i # 62. (MICH, NY, TENN, UC, USA) # 62a (UBC) # 290 as Hy molle. (MICH, MIN, NY, TENN, UC, USA) North American Musci Pieurocarpi # 260 as H. molle. (MIN, MO, NY, TENN, UC) # 442 as H. molle. (COLO, MIN, MO, NY, TENN, USA) # 446 as H. molle. (MIN, MO, NY, TENN, USA) North American Musci Pleurocarpd Supplement # 59 as H. cochlearifolium. (MIN, TENN, UC) Macoun, Canadian Cryptogams # 794 as H. pseudo-arcticum. (TRTC) Canadian Mosses # 394 as H. arcticum. (USA) # 490, i n part. (CANM, MICH, USA) Canadian Musci # 357. (CANM, NY, UC.) # 358 as H. arcticum. (CANM, MIN, NY i n part) S u l l i v a n t & Lesquereux, Musci Boreali-Americani # 304. (MICH, NY, USA.) # 451 as H, pseudo-arcticum. (MICH, NY, UC., USA) Bauer Musci europaei et amer. e x s i c c a t i # 1789. (BRNM, G, MO, NY) Musci europaea e x s i c c a t i # 1278 a. iG, NY) # 1278b. (BRNM, G, NY) # 1279 as H. molle. (BRNM, G, NY) # 1663 as H. molle var. schimperianum. (BRNM, NY) # 1664 (BRNM, CANM~,G, NY) Brotherus Musci t u r k e s t a n i c i # 120. (G, H, NY) # 121. (G, S-PA) De Notaris, Erbar. C r i t t . I t a l . Ser. II # 204 as L. duriusculum. (G, UC) Lectotype at G • # 404. (G, UC) ~ r r _ . -Dismier, Bryotheca G a l l i a e # 19. (NY) Familer, Ffcora exsiccata Bavarica; Bryophyta # 381B. (S-PA) Husnot, Musci G a l l i a e # 293 as H. molle. (G, NY) # 495 as H, alpe s t r e . (G, NY) # 692. (G) Kerner, F l o r a Exsiccata Austro-Huijgarica # 1922. (BP, BRNM, G, LE, MIN, MO, NY) Levier, Bryotheca Levier # 711. (S-PA) Limpricht, Bryotheca S i l e s i a n a # 90. (B, BP, LE, NY) 131 Lisowski, Bryotheca Polonica Fasc. IX. # 265 as H. alpinum. (LE, S-PA) Fasc. X, # 297. (BP, CAN, LE) Fasc. XI. # 319. (BP, CAN) Fasc. XXII. # 593 as H. palustre. (CAN) Fasc. XXV. # 668. (BP, CAN) Fasc. XLIX. # 1266. (BP. LE) Mougeot, Nestler & Schimper, Stirpes Criptogamae Kogeso-Rhenanae # 730 as H. molle. (G, UBC) Museo H i s t . Natur. Vindobonensi, Cryptogamae exsiccatae # 4260 as H. molle. (NY, t h i s p a r t i c u l a r specimen i s an admixture of H. molle and H. dilatatum) Noguchi & H a t t o r i , Musci Japonica Ser. 8. # 372 as H_. tsurugizanicum, (MICH, TENN, UC) Pi l o u s , Musci cechoslovenici e x s i c c a t i # 412. (G) #466. (G) # 487. (G) i # 798. (G) # 1177 as H. molle. (C, G) Rabenhorst, Bryotheca europaea # 899. (G, NY) Wilson, Musci B r i t a n n i c i # 384. (G, NY) Verdoorn, Musci S e l e c t i et C r i t i c i Ser. XI, # 272. (MICH, MO, NY, TENN, UC) Zetterstedt, Zett. Muse. pyr. # 251 as H. molle. (CAN, NY) ? Krytogamae e x s i c c a t i # 400. (NY) Selected Specimens Examined Canada B r i t i s h Columbia New.Denver, Slocan Lake; McFadden. ^UBC) Osoyoos Lake; Macoun 29 May 1895 as C. arcticum. (CAN) Macleod's Lake, 55°N; Macoun 2396 as H. s m i t h i i . (NY) Beaton, S e l k i r k Mtns., Sable Creek; Tusco Oct. 1962. (UBC) Coffee Creek, 4 miles S. of Ainsworth; Jamieson 20 Sept 1975 (UBC) Alberta L i t t l e Slave Lake; Mrs. Roy as H. s m i t h i i . (USA) Kananaska Co.; Macoun 3 Aug 1880. (TENN) Ontario Algoma d i s t r i e t , near Mica Bay; Sharp CM-636. (TENN, UBC) Thunder Bay d i s t r i c t , Kakabeka F a l l s ; Macoun 14 J u l y 1869. (CANM, NY) Algonquin Park, Petawana River; Macoun 24 J u l y 1900. (CAN) Ottawa d i s t r i c t ; Macoun 8 Aug 1905. (CAN) Lake Nipogon; Moser 1 J u l y 1884. Quebec Gaspe Co., Mt, Albert; A l l e n 30 J u l y 1881. (NY) St. Paul, Montmagmy; Gagnon & Masson 11206, (NY) Mont St. H i l a i r e ; Dupret 7 Sept 1907. (CAN) Pare du Mont Tremblant, R i v i e r e La Diablej Herman 16664. (CAN) Mont Shefford, cte de Sheffond; Le Blanc 2530 (NY) 132 Table Top Mtn.j A l l e n 10 Aug 1881. (NY) New Brunswick Grand F a l l s , Fish hatchery, Feirane Falls? Habeeb 355, (NY) Queens Co., Cannaan Forks; Macoun 1899. (CAN) Albert Co., Fundy National Park, t r a i l to Third Vault F a l l s 5 Ireland 11470. (UBC) Nova Scotia Cape Breton I s . , Cape Dauphin; Nichols July-Aug 1914.(NY) Cape Breton I s . , Indian Brook; Nichols 9 Aug 1909. (NY) Labrador Caribou River; Wickes 25 July 1938. (USA) Chu r c h i l l F a l l s , Bridge Camp area; Brassard 5330. (NFLD) Newfoundland Squires National Park, N. of Deer Lake, Humber R,; Norris 4085, (HSC) Birchy Cove; Waghorne 21 Aug 1895. (MIN, NY) United States Alaska Kodiak Group, Raspberry I. Raspberry Straight, Port V i t a ; Eyerdam 880. (TENNJ S - P A ) Washington Clallam Co., Olympic National Park, OlymptceHotsprings; Svilha 793. (WTU) C a l i f o r n i a Inyo Co., Inyo National Forest, along t r a i l on S. side of Lake Sabrina; Jamieson 5389. (UBC) Idaho" Idaho Co., Nez Perce National Forest, Red River D i s t r i c t ; Lems M60 as H. molle, (MICH) Nevada White Pine Co., Snake Mtns,, Nevada National Forest; Lawton 2810 as H. molle. (USA) Arizona Santa Cruz Co., Santa Rita Mtns.; Bartram 156. (MY, USA) Apache Co., White Mtns., W, fork of L i t t l e Colorado R.s Dybdall R 264. (Museum of N. Arizona) Montana Glacier Co., Glacier National Park, Reynolds Creek; Hermann 20433. (Personal herbarium of F. J. Hermann) Missoula Co., Rattlesnake Campground; Sharp M-41. (TENN) Belt Mountains; Williams 19 Sept 1891 as H. arcticum. (MIN) Wyoming Carbon Co., M i l l Creek; Porter 27 June 1934 as H. molle. i n North American Musci P e r f e c t i # 290. (TENN, USA, MIN, MO, NY, UC) Johnson Co., Buffalo Tensleep Rd., Porter 1638. (TENN) Park Co., E. of Beartooth Lake; Conard 21 Aug 1953. (UBC) Medicine Bow Mtns., E. of Saratoga; Sharp 550. (TENN) Colorado Larimer Co., Rocky Mountain National Park, Larkspur Creek; Hermann 25989a. (Personal herbarium of F. J. Hermann) Mineral Co., F a l l s Creek, NE of Pagosa Springs; Hermann 23343. (COLO) 133 La Plata Co., Above V a l l e c i t o ; Knowlton 85 as H. alpinum. (USA) Boulder Co., NW of Eldora, Middle Branch Creek; Hermann 24311. (WTU) Outlet of Corona Lake; Grout 20 July 1914 as H. dilatatum i n North American Musci Pleurocarpi # 446. (TENN, MIN, MO, NY* USA) New Mexico Rio Arriba Co., Brazos Canyon; Stanley & Bollman 10794. (NY, USA) Santa Fe Canyon; Arsene 20335, (USA) Utah Duchesne Co,, Uinta Mtns,, Ottoson Basin; Flowers 9141, (WTU) Minnesota Cook Co., Grand Marais; Holzinger 19 July 1902 i n North American Musci Pleurocarpi # 260. (NY, TENN, MIN, MO, UC) New York Greene Co., C a t s k i l l Mtns,, Haines F a l l s ; Hermannl4338 1/2, (MICH) Essex Co., St, Huberts; Ketchledge 723. (UBC) Vermont Windam Co., Stratton; Grout 28 June 1926 i n North American Musci P e r f e c t i 62, (TENN) Bennington Co., Manchester; Grout 28 June 1931 i n North American Musci P e r f e c t i 62. (UBC) New Hampshire Belknap Co., Mt. Belknap, G i l f o r d ; Carter 5 Sept 1904, (USA) Warren, Baker's River; Faxon 10 July 1886. (NY) Mt, Washington, Great Gulf; Faxon 29 July 1886. (NY) Maine Mt, Desert Island, Witches Hole; Patterson 208. (NY) Massachusetts Berkshire Co., P i t t s f i e l d , Lulu Brook; Rice 4 June 1942. (NY, as H. dilatatum; TENN, as H, molle) Connecticutt Ansonia; Allen 29 Oct 1880. (NY) q V i r g i n i a Madison Co., Shenandoah National Park; Patterson 1195, (NY) Tennessee Sevier Co., Great Smokey Mountain National Park, Laurel F a l l s ; Sharp 15 Sept 1935 as•- H. cochlearifo 1 ium i n North American Musci Pleurocarpi Supplement 59. (TENN, MIN, UC) Sevier Co., Roaring Fork; Sharp 36211. (TENN) North Carolina Yancey Co., Blue Ridge Parkway, Crabtree F a l l s ; Jamieson 4875. (UBC) Jackson Co., Soco F a l l s near Junaluska Lake; Welch 2860.(TENN) Greenland Nugssuag Pen., Nugssuag; Holmen 15582- (LE, S-PA, UBC) , -Disco Fjord, Kuanit; P o r s i l d 969. (S-PA) Faroes Fugelefjord Bygd; Jensen 19 May 1896. (CAN, NY) 134 Great B r i t a i n Scotland Clova; Fergusson July 1876. Schottland; Schimper 1868. (S-PA) Glen Coe, Rievers Glen, Binstead & Dixon 16 July 1898. (NY) Wales North Wales, Aber; Hunt 16 May 1868. (S-PA) Norway Gausta; Jaederholm July 1895. (S-PA) Opdal; Kaurin Aug. 1881, (S-PA) Lomsaggerej Bryhn July 1879. (S-PA) Nordland, Salten, Nyman 28 July 1893. (S-PA) Finmarken, Kaafjord; Zetterstedt 13 July 1868. (NY) Sweden Smaland, Hults Hesslas dam; Larsson 11 Sept. 1941. (S-PA) Bahusia, Kristendal; Arven 3 July 1913. (S-PA) Upland, A t l y l n Sundstra; Lindberg June 1855. (S-PA) Vestmanland, Kingsor Runnakvarn; Ahrling 23 Aug 1880. (S-PA) Varmland, Ostmarks sn pa Ranneberget; Larsson 24 Aug, 1936. (S-PA) Dalarna, Norrbarki; Hakelier 4 July 1965. (S-PA) Halsingland, Bergsjo, Elfasen- Collinder 3 July 1877. (S-PA) Harjedalen, Lyingdaleri Storsjo; Thedenius fiug 1842. (S-PA) Jamtland, B o r g a f j a l l t , Rankanlet, Frostvikens; Nyman 1 Aug. 1947. (S-PA) Angermanland, Sabra Klochersbacen; A r n e l l 26 Aug. 1874, (S-BA) Asele Lappmark, Vilheinimia; Moller 22 July 1914. (S-PA) Lycksele Lappmark, Tama; Stenholm 12 July 1924{. (S-PA) Lapponia Lulensis, Sarjekensis, Kotikjokk; Jens;eh & Ar n e l l 24 July 1902, (S-PA) Tornea Lappmark, Jukkasjarvi, Abisko National Park; Persson & Gjaerevoll 15 Aug. 1944. (S-PA) Finland Lapponia pomojensis, Bakalda; Brotherus 18 July 1872. (NY) Soviet Union. S i b e r i a , A l t a i Mtns., Belokurikka; Bardunov 5 June 1966. , ( N I C H ) Siberia, Akmolinsk. D i s t r . Atbalarky Ulu-tau; Ganeschin 1717, (H-BR) Bryotheca Caucasia, Ossetia; Brotherus 26 May 1887. (H-BR) Siberia, Jenesei, Antis ferova; A r n e l l 27 June 1876. (S-PA) Turkestan, Thian Schan, in^ywalle f l . Narinkol.; Brotherus 27 July 1896. (S-PA) Lapponia lmandra; A. Kohlman 24 July 1887 (C, as Amblystegium  molle var. alpinum) France Chamonix; Bernet J u l l i e t 1868, (G) Switzerland V a l a i s , Grand St, Bernard; Jaquet 18 Aug. 1926. (S-PA) Val a i s , Mattmark; Micholson & Dixon 13. (BM) Tessin, Lago Campoluigo; Conti Aout 1894. (G) Austria Steiermark, Schladming; Breidler Aug 1871, (G) T i r o l , Innervillgarten; Ganders 15 Sept 1881. (BP) Salzburg, Lungau, Lessachthal; Breidler 16 June 1885. (BP) Vorarlberg, St. Gallenkirsch; Hooch 26 Oct. 1928. ( s - P A ) Karnten, Tandelapha bei Malta; Breidler 4 Aug. 1880. ( s - P A ) 135. I t a l y Prov. Comensis, Valle de Darengo; A r t a r i a 15 Aug. 1898. (S-PA, LE) Campello-Monte, Porv. Noraro Pedemonti, Bei Dannai; Levier 5 Aug. 1904 i n Bryotheca I t a l i c a 102. (S-PA) Macuguaga, Val Anyasca; Nicholson & Dixon 10 July 1913. (BM) Czechoslovakia Slovenia, Vysoke Tatry; Smarda 13 July 1937. (Moravian) Moravia, Hruly Jesenik; Smarda July 1947. (Moravian) Riesengebirges (= Krkonse), Kleiner Teich; Schiffner 13 June 1886, (S-PA) Poland Montes T a t r i Occ; Lisowski 17 Aug 1956, i n Bryotheca Polonica Fasc. X. # 297. (BP) Roumania Carpat, merid., Montes Fogarasi; Vajada 13 Aug. 1966. (BP) Carpat. merid., Montes Ret y l z l a t ; Vajada 3 Aug. 1969. (BP) Bulgaria R i l a Planina, c i r c a Gam Koruje; Podpera 7 Aug. 1908. (S-PA) Borovec; Kovacs 29 Oct. 1956. (BP) Balkan, Trojanskapt, Katoferskap; Kuc 30 Aug 1960. (BP) Vitosa planima, Stara R e l l a ; Podpera 17 July 1908. (G) Asia Kungei Altau, Brotherus Aug. 1896 i n Musci Turkestani # 120. (H-BR, NY) Kashmir, Gulmarg? Duthie 3 June 1892. (H-^ BR) China' Chensi (=Shensi) Prov., Sinn t s a i ; Licent 209. (BM) Japan Mutsu PVW.r Towada? Uemotsu 14 Aug, 1910. (H-BR) Shinano Prov., Mt., Shirouma; Tishiba 17 Aug. 1909. (H-BR) Kukuoka Prov., Kyushu, Seburi Mtns.; Amakawa 610. (NICH) - ! Nigano Co,, Okura, Minami-saku; Shimiju Aug. 1952 as H, tsurug-zanicum i n Musdi Japonica # 372. (TENN) "~ Mt. Hokkoda; Uemtsu July 1910. (NY) 136 Hygrohypnum sm i t h i i (Sw. i n L i l j . ) Broth, Nat. Pf, 1(3):1039. 1909. Ledtotype: Sweden, Harjedalen, Funnasdalen? Thedenius. (S-PA) Lesikea s m i t h i i Sw. i n L i l j . , Svensk. F l . ed. 3:549. 1816. Hypnum arcticum Somm. i n Wahlenb., F l . Lapp. Suppl. 65.2. 1826. Hypnum molle var. arcticum (Somm.) Aongstr. i n F r i e s . , Summ, Beg. Skand. 1:83. 1846. Limnobium arcticum (Somm.) Schimp., Bryol. Eur. 6:70, 578. 1853. Stereodon arcticus (Somm.) Mi t t , , Journ. Limn. Soc. 8:42. 1864. Hypnum sm i t h i i (Sw.) Lindb,, Act. Soc. Sc. Fennica 10:277. 1872, Amblystegium s m i t h i i (Sw.) Lindb., Musci Scand. 33. 1879. Hypnum tor r e n t i s C. Muell. et Kindb. i n Macoun, Cat. Canad, PI. 6:243. 1892. Calliergon arcticum (Somm.) Kindb., Canad. Rec. Sc. 6(2):72. 1894. Hygrohypnum arcticum (Somm.) Loesk., Verh, Bot. Ver. Brandenburg 46:198. 1905. Hygrohypnum crassinervium Warnst. ex Bauer. Hedwigia 54:152 - 153. f. 22. 1913. Names of taxa for which the appropriate l i t e r a t u r e was not available during t h i s study. Amblystegium s m i t h i i (Sw.) Lindb. i n Hartm., Handb. Skand. F l . ed, 10. 2:6. 1871. Plants forming very s t i f f , coarse, loosely to t i g h t l y woven tuf t s or mats. Color variable, d u l l dark green, oMvaceous-green, blackish-green or black, often modified by golden-green or golden-brown mottling, es p e c i a l l y i n the stem or branch t i p s . Stems 1 to 8 cm long, prostrate or ascending at the t i p s . Branching variable, nearly unbranched or frequently and i r r e g -u l a r l y branched, branches remaining prostrate and attaining dimensions simi l a r to the stems, or branches short and ascending to erect? older extremities of both stems and branches becoming denuded or remaining clothed i n persistent, but shredded leaf bases. Stems normally eradicu-lose but those plants which bear many short, erect or ascending branches may be densely radiculose. Stem cross-sectionarevealing 3 to 4 rows of small, thick-walled, brownish c o r t i c a l cells? medullary c e l l s becoming larger and thinner walled toward the middle, becoming brown with age; cen-t r a l strand well developed. Leaves variable? (0.6) 0.8 - 1,2 (1.5) mm long X (0.4) 0.6 - 1.2 (1,4) mm wide? shape ovate, broadly ovate to orbicular, sometimes transverse ovate; apex obtuse or rounded, sometimes almost acute or abruptly tapering to an obtuse point; margins entire or weakly denticulate, plane throughout or s l i g h t l y recurved near the base; leaves plane or broadly and shallowly concave; costa variable; usually coarse, single to 3/4, often variously forked, occasionally short and double; leaves sometimes rather s t i f f l y decurrent at the base. When wet the leaves are s t i f f l y , but loosely imbricated to erect spreading, upon drying the leaves shrink l a t e r a l l y s l i g h t l y and twist. Areolation variable: Median leaf c e l l s rhomboid, fusiform, baciliform or fusiform to l i n e a r flexuose; 22 - 48 (64) mm long X (4) 5 - 7 (10) mm wide; apical c e l l s oval rhombic or rounded; Margins often, but not always, bordered by an i l l - d e f i n e d row of short c e l l s ; c e l l s generally becoming longer, wider and more incrassate toward the base, i n older leaves the basal c e l l s are often shiny yellow i n color, p i t s few to none; alar c e l l s s i m i l a r l y incrassate and yellow, variously quadrate or rectangular, but not forming a c l e a r l y recognizable group. Plants monoicous. Perigonia ovate, perigonial leaves ovate, to 0.6 mm 138 long, concave imbricate, ecostate, entire. Outer and middle p e r i -chaetial leaves ovate, ovate-lanceolate or sometimes s l i g h t l y elongate-ttianguiar? costa single to midleaf, short and double or almost absent? margins entire, plane or recurved at the base; apex obtuse, variously entire or denticulate, leaf lamina plane or p l i c a t e . Inner perichaetial leaves up to 5 mm long, usually 2.5 to 4 mm long, costa single and strong, 2 - 4 p l i c a e , margins entire and recurved, apex obtuse. Seta 8 - 17 mm long, straight or s l i g h t l y curved, red or reddish-brown, smooth; Capsule t y p i c a l for the genus. Peristome as i n the genus? annulus of two rows of cells? endostome with 1 to 3 poorly to well developed c i l i a . Spores yellow to brown, 13 to 21 um i n diameter, usually 16 to 19 um. Hygrohypnum sm i t h i i may be recognized by i t s coarse, r i g i d habit and the usually broadly ovate to or b i c u l a r , loosely imbricated to spreading leaves and the stout, generally single costa (Fig. 33 a - e). Of these features, the r i g i d habit i s constant, while the others may vary. In spite of t h i s v a r i a t i o n , these characters i n combination are diagnostic for the species. A number of features held by e a r l i e r authors as useful i n recognizing the species have been shown to be unreliable by the present study. Husnot (1894) and Lawton (1971) respectively described the stem as ranging from 3 - 5 cm and 1 - 4 cm long. The present studies have revealed continuous v a r i a t i o n i n stem length from 1 - 8 cm. North American plants are often shorter than European ones, but the differences do not appear s i g n i f i c a n t . Schimper (1853, 1860, 1876), Braithwaite 11898), Dixon (1896, 1924), Grout (1931) and Lawton (1971) commented upon the slender nature of the 139 species. I f the thickness of a stem i s correctly interpreted here to mean the distance between the t i p of one leaf to that of another leaf on the opposite side of a moist stem, then the feature i s too variable and too subjective a feature to be useful. The leaves of Hygrohypnum s m i t h i i are generally described as broadly ovate to orbicular. I t i s not unusual to observe leaves that may be ovate, oblong ovate or almost triangular (Pig. 33 c, d, & e). Further, the leaves are often described as being 1 mm or less i n length. In natural populations, leaves attaining lengths of 1.5 mm are not unusual. Plants grown i n culture have born leaves up to 2.0 mm long. The margin i n the upper half of the leaf i s frequently described as having an i l l - d e f i n e d border of short c e l l s (Fig. 34 c ) . Such i s not always the case as can be seen i n Fig. 34 e. The median leaf c e l l s are generally quite uniform. Occasionally the median areolation exhibits very wide c e l l s interspersed among c e l l s of more t y p i c a l dimensions (Fig. 34 f ) . The alar c e l l s are undifferentiated (Fig. 34 g) or they form a small, i l l - d e f i n e d girottp of small, quadrate, incrassate c e l l s (Fig. 34 h). Occasionally Hygrohypnum s m i t h i i has been confused with H, b e s t i i and M* dilatatum. I t i s s i g n i f i c a n t that a l l three are t y p i c a l l y very coarse to the touch. Hygrohypnum s m i t h i i i s most readily distinguished from H. b e s t i i by the marginal leaf c e l l s . Compare F i g . 34 c & e with F i g . 37 e & f. In Western North America very small specimens of H. s m i t h i i and H. duriusculum may be confused. Both species may assume a habit i n which prostrate stems bear numerous short, ascending to erect branches. They may be d i f f e r e n t i a t e d best on the basis of th e i r costae. Further, H.- duriusculum loses considerable of i t s r i d l d i t y upon moistening, whereas H_. s m i t h i i does not. The median leaf c e l l s of H. s m i t h i i are usually 22 to 48 um long, whereas those of H, duriu-140 sculum are usually 45 to 70 um long. The alar c e l l s of H. duriusculum t y p i c a l l y exhibit more conspicuous d i f f e r e n t i a t i o n than those of H. s m i t h i i . Personal f i e l d experience with Hygrohypnum s m i t h i i has been confined to Southern B r i t i s h Columbia. In t h i s area the species has been observed under a variety of conditions. In Kokanee Creek and at Whistler Mtn. H. sm i t h i i was observed growing on i r r i g a t e d rocks. Both l o c a l i t i e s were at elevations i n excess of 4000 feet. At Stagleap Pass H. smi t h i i was collected from a very sluggish and seepy stream. The plants were heavily encased by dark, humic s o i l . This feature i s most unusual, for species of Hygrohypnum normally occur i n clean water. At Kokanee Lake, H, sm i t h i i was observed i n another equally unusual s i t u a t i o n . Only very rarel y have I seen any species of Hygrohypnum growing completely submerged. At the outlet of Kokanee Lake H. sm i t h i i was seen growing i n extensive mats on large boulders whose tops were just a few inches below the lake surface. The mats of H. smi t h i i covered a surface area of approximately 30 square feet. Hygrohypnum smithi i was o r i g i n a l l y described as Leskea sm i t h i i by Swartz i n L i l j e b l a d ' s (1816) Svensk Flora. Schimper (1853) described Limnobium arcticum and based the taxon on Hypnum arcticum Sommerfeld, which was i t s e l f described i n Wahlenberg (1826) . In l i t e r a t u r e not seen LMdberg (Lindberg i n Hartman, 1871) evidently recognized the cons p e c i f i c i t y of the Swartz and Sommerfeldtitaxa and the p r i o r i t y of the Swartz name for he recognized Amblystegium s m i t h i i (Sw.) Lindb. Although Lindberg's (1872, 1879) opinion of the generic position of the plant varied from that of 1871 i t i s clear that he s t i l l held the Swartz and Sommerfeldt taxa as conspecific. Neither Swartz nor Sommerfeldt designated any specimens, although they specified geo-graphical areas. Swartz indicated Norrige and Sommerfeldt designated Saltdalen, 141 Nordlandiae. Schimper (1853) ci t e d several specimens, of which the following are pertinent: Saltdalen, Nordlandiae, Sommerfeldt; Christiana, Norvige, B l y t t , Schimper; Harjedalen prope Funnasdalen, Thedenius; Kleiner Teich, Sendtner. Apparent duplicates of the B l y t t , Thedenius and Sendtner specimens are at S-PA. In the Schimper herbarium at BM i s a specimen from Christiana, Norvige for which a c o l l e c t o r i s not designated. I t may well be Schimper's own c o l l e c t i o n ; t h i s cannot be conclusively proven. These specimens are pertinent for they seem to establish the con s p e c i f i c i t y of the Sommerfeldt and Schimper concepts of Hypnum arcticum and Limnobium arc- ticum. Then, i f one can assume that Lindberg (1871, i n Hartmann) accurately recognized the conspecificity of Leskea s m i t h i i Sw. and Limnobium arcticum Schimp,, then a neotype can be selected from the specimens cited by Schimper, With t h i s rationale a Thedenius specimen at S-PA i s designated as the lec t o -type for Hygrohypnum s m i t h i i (Sw. i n L i l j . ) Broth. 142 P i g . 33 a - h. V a r i a t i o n i n l e a f shape and the habit of l e a f y shoots of Hygrohypnum s m i t h i i . a - e. Fo l i a g e leaves. f - h. Leafy shoots i n the moist co n d i t i o n . Scales a - e. ; I 1mm I f - h. shoots are approximately 0.75 cm long 143 144 Pig. 34 a - h. C e l l u l a r d e t a i l s of the perichaetial and foliage leaves of Hygrohypnum s m i t h i i . a. Foliage leaf apex. b. Perich a e t i a l leaf apex. c and e. Marginal c e l l s of foliage leaves d and f . Median leaf c e l l s of foliage leaves g - h. A l a r c e l l s of foliage leaves Scale: a, c - f . I 100um I b, g - h. I 100um I 145 146 4-Fig. 3 5 . Hygrohypnum sm i t h i i 147 Exs i c c a t i Examined Bauer, Musci europaei et americani e x s i c c a t i # 2289. (BRMN) De Notaris, Erbar, C r i t t . I t a l , # 306 as H. arcticum. (NY, UBC) Levier, Bryotheca I t a l i c a # 512 as L. molle. (S-PA) Limpricht, Bryotheca S i l e s i a c a # 292 as Hypnum arcticum. (BP, LE) Lisowski, Bryotheca Pblonica Fasc. X # 295. (BP, LE) Fasc. XXIV # 639. (BP, LE) Macoun, Canadian Musci # 358 as arcticum. (NY, TENN, UC) # 503 as H. g o u l a r d i i . (MICH, MIN, TRTC, USA) Rabenhorst, Bfeyotheca europaea # 1142 as L. arcticum. (LE) Su l l i v a h t and Lesquereux, Musci Boreali Americani # 194 as H. molle. (MICH, NY, TENN) Selected Specimens Examined Canada B r i t i s h Columbia Vancouver Island, Strathcona Provincial Park, Golden Hind? Boas 356. (UBC) Bulkley Range; Boas 714. (UBC) Lake of the Hanging Glaciers; MacFadden 1096. (UBC) Skeena R., south of Harrison L., Schofield and Boas 21269. (UBC) Haines Highway, 54 mi. NW of Haines? Hermann 21794. (CAN, MICH, NY, USA) Kokanee Glacier Provincial Park, Kokanee L.? Jamieson 5614. (UBC) Garibaldi Provincial Park, whistler Mtn,? Schofield and Jamieson. (UBC) Alberta Jasper National Park, Tonquin Valley? MacFadden 27 July 1926. (UBC) Quebec Gaspe, St, Anne R,; Macoun 29 Aug. 1890. (CAN) An t i c o s t i I., Bececii R., Macoun Aug. 1890. (CAN) Nova Scotia Cape Breton I. , Valley of Barrasois; Nichols 1948. (NY) Newfoundland Humber R. D i s t r i c t , E. of Blow-Me-Down- Mtn., Williams 1601. (CAMN$ HSC, MICH) Sops Arm, Approx. 5 mi. S., Norris 4198. (HSC) Trout River, approx. 4 mi. E. Norris 4655. (HSC) United States Alaska Prince William Sound, Krii/fcrfat I., Thrum Bay; Eyerdam 589 (MICH) Washington Olympic National Park, Solduc Hotsprings, Dear Lake Trail? Schofield, Ireland s Boas 19473. (UBC) Snohomish Co., Monte Csisto, T s a i l to Glacier Basin? Schofield 20123. (UBC) 148 C a l i f o r n i a Mono Co. Harvey Monroe Hal l Natural Area, Cabin Creek; Catchenda 4788. (CAN, MICH, TENN) T r i n i t y Co., i n r i v u l e t below E. Weaver L,; Norris 9415 (HSC) Montana Flathead Co., Glacier National Park, Hidden Lake T r a i l S. of Logan Pass; Hermann 18315, (CAN, USA) Lincoln Co., Cabinet Mtns., Leigh Lake T r a i l ; Schofield 11978. (CAN, HSC, NY) Colorado Boulder Co., NW of Eldora, Diamond Lake T r a i l ; Hermann 26660. (Herbarium of F. J . Hermann, Dupl. - UBC) Greenland Nigerdleg; Holmen 63-146. (NY, UBC) Ilimaussag Peninsula, Dyrnaes; Holmen & Steere 62-584. (NY, UBC) Tunagdliarfik Fjord, Narassarssuag; Holmen & Steere 62-607. (NY, UBC) Iceland N. W. Iceland, Strandasyala, Reyhyavik; Johannson 3 Sept 1967. (UBC) Faroes Bordo, Graverdal, Jansen 17 May 1896. (NY, UAC, UBC) Sweden Harjedalen, Tannas, Funnasdalen; Thedenius 1842, (S-PA, Lectotype) Jamtland, Frostviken; Hulphers 1 Sept 1934. (S-PA) Asele Lappmark, Vilhelmina; Moller 20 July 1914. (S-PA) Lycksele Lappmark, Tama; Angstrom. (S-PA) Lapponia Tornensis, Mellan, J i k k a s j a r v i ; Jaderhoto 29 July 1914, (S-PA) Norway C h r i s t i a n i a , Bogstadaas; Zetterstedt & Wickbom 16 June 1870, (S-PA) Kongsvold, Dovre; Kindberg 1885. (NY, S-PA) Nordland, Helgeland, Lerskaradalen Stopefjeld; B l y t t & A r n e l l 20 Aug. 1870. (S-PA) Finnmarken, Hammersfest; Jorgensen 15 Oct. 1888. (S-PA) Finland Lapponia imandrae, Urupjok, Haarakoski; Kihlman 3 July 1892, (S-PA) Lps. Salmijarvi, Kuotsjarvi; Roivainen July 1927. (NY) Soviet Union Peninsula Kolaensis, Montes Chiciny; Schljakov 20 Aug. 1947 as Hep aticae et Musci URSS Exs i c c a t i 9 49. (CAN) Austria T i r o l Ferwell; Lorentz Sept 1866. (BP) Steiermark, Sturzbach am Ostablang des Kn a l l s t e i n i n der Solk; Breidler 4 Aug. 1877. (BP) Vorarlberg, Gampadelthal i n der Rhatikonkette bei Schruns; Breidler 19 July 1882. (BP) Karnteri, "Klein Eland" im Maltathal; Breidler 25 Aug. 1880. (BE) Switzerland Bern Canton, Oberlager am Faulhorn; Culmann 10 Aug. 1908. as Musci europaei e x s i c c a t i # 650. (S-PA) Scotland Aberdeen, Head of Glen C a l l a t e r ; C r o a l l 11 Aug 1853. (CAN) 149 Ben Lawers; Gardner 1838. (CAN) Ben Mhur; Schimper 1869. (BP, S-PA) Canlochan Glen, Forfar; Hunt 13 July 1868. (BP) Clova; ex dons E, G. Br i t t o n 1868 ?? (NY) France Pyrenees centrales, Crabioules et Tousse de Maupas; Zetter-stedt 18 Sept 1856 as Zett. Musci pyr, # 252. (CAN, S-PA) I t a l y Monte Adamello, Schneebach an der Mondronhutte; Kern 27 Aug 1901. (BP) Poland Montes T a t r i A l t i ; Lisowski 29 Aug. 1956 as Bryoth, Pol. Fasc. XXIV # 639. (CAMN) C zecko slovak i a Kleiner Teich; Herausgeber 6 Aug 1868 as Bryo. S i l e s . # 292, (BP, NY) 150 Hygrohypnum b e s t i i (Ren. et Bryhn) Holz., Bryologist 4:12, 22. 1901. Lectotype; Montana, v i c i n i t y of Lake McDonald, Avalanche Basin. Leg: J. M. Holzinger and J. B. Blake 29 July 1898. (NY) Hypnum molle ssp. b e s t i i Ren. et Bryhn, B u l l . d. L'Acad. Int. d. Geog. Bot. 10:7. 1901. Hypnum b e s t i i .(Ren, et Bryhn) Ren. et Bryhn, Rev. Bryol. 28: 8. 1901. Limnobium b e s t i i (Ren. et Bryhn) Holz., Bryol. 4:22. 1901. Hygrohypnum molle ssp. b e s t i i (Ren. et Bryhn) Broth., Nat. P f l . Ed. 1, 2:1040. 1909. Hygrohypnum molle var. b e s t i i (Ren. et Bryhn) Hab., Rhodora 54:156. 1952. Plants very s t i f f and coarse, rarely soft, i n loosely woven mats or t u f t s . Color usually d i r t y olive-green, often dirty-yellow, often d u l l yellowish-green with golden mottling, especially near stem and branch apices, rarely bright-green. Stems(1) 3 - 7 (12) cm long, denuded i n older extremities i n s t i f f forms, f o l i o s e throughout i n some soft forms; r i g i d leaf bases and decurrent wings c h a r a c t e r i s t i c a l l y persistent on the other-wise denuded posterior extremities of stems i n s t i f f , coarse forms. Stem cross-sections revealing 2 to 4 rows of small, thick-walled c o r t i c a l c e l l s , yellow-brown to reddish-brown i n color; medullary c e l l s larger, usually thinner-walled, occasionally becoming incrassate with age i n s t i f f , r i g i d stems; central strand absent or very weak. Branching irregular; i n very s t i f f forms branches ascending or erect from prostrate, interwoven, denuded stems; i n softer forms leafy stems and branches intertwine i n loosely woven t u f t s . Eradiculose. 1 5 1 * Leaves variable. Somewhat d i s t a n t l y spaced. Attitude on the stem variable from the wet to dry condition; when wet leaves weakly appressed, spreading or erect, sometimes s l i g h t l y secund; variously contorted when dry, often twisting to the l e f t i n the upper half. Leaves (1) 1.5 - 2.5 (3) mm long X 1 - 1.5 (2.0) mm wide; shape ovate to broadly ovate, some-times s l i g h t l y asymmetrical; margins entire, becoming somewhat uneven i n the apex, rarely weakly denticulate; apex obtuse or somewhat acute; leaves plane to broadly and shallowly concave; strongly decurrent to scarecely so, leaves often removed with d i f f i c u l t y from the stem because of the strong bond between the incrassate basal le a f c e l l s and the incrassate c o r t i c a l stem c e l l s ; costa variable, usually strong and double from a massive base, one or both branches reaching midleaf or beyond, or very strong and single reaching well beyond midleaf, often bearing $., 2 or rarely 3 l a t e r a l forks, less commonly weak and double, especially i n very young leaves and small branches, costa yellow-green or yellow, becoming brownish with age. Areolation variable; median leaf c e l l s l i n e a r flexuose to broadly rhombic flexuose, (40) 60 - 120 (170) am long X (2) 6 - 10 (12) um wide, median leaf c e l l s may exhibit a fa±£iy uniform width or very wide c e l l s (10 - 12 um) may be i r r e g u l a r l y interspersed among much narrower c e l l s , such va r i a t i o n occurring between leaves on the same stem and from one side to the other i n individual leaves; apical c e l l s usually rounded quadrate or rhombic, although lin e a r flexuose c e l l s up to 100 um long are not uncommon; marginal leaf c e l l s between the lower 1/3 and the upper 1/4 of the leaf vary from 60 to 250 um long; t r a n s i t i o n from median to basal c e l l s variable, l i t t l e changed or not at a l l , becoming thicker or thinner-walled, mostly becoming s l i g h t l y wider, basal c e l l s usually strongly incrassate and yellowish, turn-ing yellow-brown with age, the pigmentation often creating a radiating sun-152 burst e f f e c t , or sometimes l i t t l e or not at a l l incrassate? P i t s few to none; Alar c e l l s variable, hardly d i f f e r e n t i a t e d to an imprecisely d i f f e r -entiated group of quadrate to short rectangular, moderately incrassate c e l l s . Plants apparently dioicous, male and female plants similar.- Perigonia borne i n the a x i l s of stem leaves and large branch leaves, inner perigonial leaves ovate, 0.75 to 0.9 mm long, deeply concave, margins at Ifehe apex s l i g h t l y i r r e g u l a r to weakly denticulate, ecostatej Outer and middle p e r i -chaetial leaves ovate to ovate-lanceolate, ecostate, reflexed squarrose i n the upper half, inner perichaetial leaves long l i n e a r lanceolate, up to 2 mm,, long, costa variable, short and double, single to midleaf or absent, leaves multistratose through the middle with bistratose blades, apical margin uneven w with 1 to 4 coarse teeth. Seta 15 to 25 mm long usually 18 to 22 mm; red to dark maroon-red i n color; smooth, straight when wet, variously twisted when dry. Capsule as i n the genus, Annulus of 2 to 3 or 4 rows of deciduous c e l l s . Peristome as i n the genus, Endostome with 1 to 3 f i n e l y papillose, weakly appendiculate c i l i a between each tooth; spores pale yellow, f i n e l y papillose, 13 to 21 um i n diameter, usually 17 to 19 um. Of the broad-leafed species Hygrohypnum b e s t i i i s best recognized by 1. the very long marginal leaf c e l l s , which range from 60 to 250 um, 2. the large leaves which reach 3 mm long X 2 mm wide, and 3. the dioicous sexuality. In many cases discoloration i n the basal leaf c e l l s imparts the appearance of a radiating '^sunburst" i n the leaf base which i s t y p i c a l of the species. Hygrohypnum b e s t i i i s a very d i s t i n c t i v e species. However, certain of 153 i t s c h aracteristics are s u f f i c i e n t l y variable to overlap with other species or are simply shared with other species. The broadly ovate leaf shape which i s t y p i c a l of H. b e s t i i (Fig. 38 a, b), i s also shared by H_. molle (Fig. 44 a - e) . The leaves of H. b e s t i i are usually 1.5 to 2,5 mm long and as such are much larger than the t y p i c a l lengths of 0.9 to 1.3 mm attained by the leaves of H. molle i n Western North America. However, small plants of H. b e s t i i with tiny leaves are not i n f r e -quent and may eas i l y be confused with H_. molle. The id e n t i t y of such plants can be established only by noting of the very long marginal leaf c e l l s i n H_. b e s t i i . Both Hygrohypnum b e s t i i and H_. duriusculum are described as coarse to the touch or r i g i d and s t i f f when dry. Further, the leaves of H, b e s t i i may approach an orbicular shape that i s more t y p i c a l of H. duriusculum (Fig. 37 c ) . Again, these two species may be readily distinguished by thei r marginal leaf c e l l s , where those of H_. b e s t i i are by far the longer (Compare F i g . 38 e & f with F i g . 30 f & g). As ijtust discussed, H. b e s t i i i s generally very coarse or s t i f f to the touch when dry. Certain specimens may be r i g i d even when wet. However, i t i s not unusual to fi n d specimens that are soft and f l e x i b l e i n both the wet and dry state. Therefore, t h i s feature should be employed i n the f i e l d with some dis c r e t i o n . One unique feature of H. b e s t i i , which seems to be of uncertain taxonomic value has to do with the d i f f i c u l t y with which leaves may be removed from the stem during dissection. The bond at the point of insertion between the leaf and the stem i s exceedingly tenacious and i s reflected i n the shredded and persistent leaf bases on the older extremities of both stems and branches. The leaves w i l l invariably shred during dissection. A good deal of c o r t i c a l 154 stem tissue remains attached to the leaves.when they are removed from the stem. The attitude of the leaves upon the stems may vary s l i g h t l y between and within the wet and dry conditions. When moist the leaves are generally rather distant and loosely imbricated to s l i g h t l y spreading. In some plants, however, the leaves may be gently folded around the stem so as to be s l i g h t l y secund (Fig. 36 c ) . Upon drying the leaves normally exhibit some l a t e r a l shrinkage and concomitant twisting. Sometimes the leaves may be very s l i g h t l y f a l c a t e , but normally the leaves are quite straight. The alar c e l l s i n H. b e s t i i vary from v i r t u a l l y undifferentiated (Fig. 3 8 1 h) to an i l l - d e f i n e d group of short rectangular c e l l s (Fig. 3 8 g). Such va r i a t i o n can lead to confusion with either H. molle or H_. duriusculum. The very long marginal leaf c e l l s i n H_, b e s t i i w i l l c l e a r l y distinguish i t from these two species. The median leaf c e l l s also exhibit some rather peculiar v a r i a t i o n . In most cases the median areolation i s uniform. However, i n some plants very wide c e l l s may be i r r e g u l a r l y interspersed among c e l l s of more t y p i c a l widths; Curiously a similar s i t u a t i o n occurs i n H. s m i t h i i , which i s i t s e l f a rather coarse plant. In leaves of H_. sm i t h i i there i s l a t e r a l shrinkage and lo n g i -tudinal twisting that i s reminescent of H_. b e s t i i . This i s more a function of the r i g i d i t y of the plants than a fundamental relationship. Hygrohypnum b e s t i i was described o r i g i n a l l y from s t e r i l e material. Due to the confusion of H. b e s t i i with H. duriusculum and H. molle the dioicous nature and the existence of sporophytes i n H. b e s t i i remained Unclear u n t i l Lawton's (1966) report. Of 128 specimens examined i n d e t a i l 11 were female, 4 were male and 8 were female and bore sporophytes, Lawton (1966) pointed out that the multistratose inner perichaetial leaves contrasted the uni s t r a t -155 ose condition i n H. molle. The papillose apical c e l l s i n the perichaetial leaves of H. molle d i f f e r from the smooth c e l l s i n those of JI. b e s t i i , Hygrohypnum b e s t i i has one unusual form that occurs at f i v e widely spaced l o c a l i t i e s along the P a c i f i c Coast of North America. The plant s u p e r f i c i a l l y resembles H. ochraceum, but d i f f e r s i n the absence of the i n f l a t e d , hyaline c o r t i c a l c e l l s . Like t y p i c a l H, b e s t i i the leaves usually exceed 2 mm long, but d i f f e r through a more oblong-lanceolate leaf shape (Fig. 37 f - i ) . The costa i s stout and variously double and/or single and forked. The marginal leaf c e l l s are very long as i s t y p i c a l for H, b e s t i i . The form also d i f f e r s i n i t s complete lack of alar d i f f e r e n t i a t i o n (Fig. 38 i ) and a tendency for more regular pinnate branching. This form seems to be a lowland plant occurring from sea l e v e l to about 2000 f t , whereas H. b e s t i i i s from much higher elevations. The s t e r i l i t y of t h i s form may indicate one of two situations. One, that the plant i s dioicous, or two that the f i v e known populations represent s t e r i l e o u t l i e r s of an otherwise f e r t i l e mountain species that cannot reproduce at low elevations. That H, b e s t i i i s dioicous i s no doubt s i g n i f i c a n t . Hygrohypnum b e s t i i has long been viewed as a Western North American endemic;(Lawton, 1971; Schofield, 1969). That Habeeb (1952) reported the species from Albert and V i c t o r i a counties New Brunswick seems to have gone en t i r e l y unnoticed. The present study has discovered other l o c a l i t i e s for H. b e s t i i i n Eastern North America, extending from the upper peninsula of Michigan to the Gaspe Peninsula, Quebec and Cape Breton Highlands, Nova Scotia. In Index Muscorum Vol. 5 Wijk et a l . (1969) reported H. b e s t i i from Europe. I t i s possible that the species might be discovered i n Scandanavia, but as yet I have seen no material to support t h i s assertion. 156 Although H. b e s t i i i s common throughout Western North America, my own f i e l d experience has been limited to f i v e l o c a l i t i e s i n south-ern B r i t i s h Columbia and three i n northern C a l i f o r n i a . In these areas 3* b e s t i i has been observed i n a variety of habitats. The elevational range, as I know i t , extends from sea l e v e l to 6500 feet. In .'some cases the species grown on submerged rocks i n clear, cold mountain streams. In other cases, i t grows on rocks i n small, s i l t - : a i l d sand-ladened, apparently seasonal r i v u l e t s . In such r i v u l e t s the water tumbles over the rocks i n small cascades or slowly seeps over them. Frequently considerable humic s i l t i s present. Organic or inorganic s i l t and sand accumulate i n the plants under such conditions. At sea l e v e l the form resembling H_, ochraceum has been observed growing on sandstone i n a seepy roadside d i t c h . I t has also been seen i n a clear, s i l t - f r e e stream at an elevation of about 300 feet. I have been unable to draw any correlation between the coarseness or softness of H_. b e s t i i and v a r i a t i o n i n habitat. Renauld (1901) described Hypnum (Limnobium) molle Dicks, ssp.bestii Ren .et Bryhn based on a J. M. Holzinger c o l l e c t i o n of 29 July 1898 from Avalanche Basin, Montana at an elevation of 1500 m. Renauld (1901a) pub-lished a very similar and somewhat redundant paper redescribing the plant as Hypnum (Limnobium) b e s t i i Ren et Bryhn. I t would seem that he wished to elevate the plant to the rank of species. However, within the text he remarks, "je cr o i s que l e H. b e s t i i R. et B. sera mieux a sa place comme sous-espece subordonnee au H. molle Dicks, (sensu s t r i c t o ) . " Here again, he places the plant as subordinate to H_. molle. Wijk et a l . (1964) credited Brotherus (1909) with the authorship of Hygrohypnum b e s t i i . An examination of Brotherus* treatment reveals two important points. One the presentation of H. b e s t i i was preceded by that of 157 Hygrohypnum molle (Dicks.) Secondly, the name H. b e s t i i , i t s e l f , was immediately preceded by an asterisk, which denoted subspecific status. For some reason Wijk et a l . overlooked the asterisk. I t seems clear that Brotherus wished to treat H. b e s t i i as a subspecies and not as a species. Brotherus (1925) presented a simi l a r treatment. John Holzinger (1901) published a note commenting on Hypnum (Limnobium  b e s t i i Ren et Rryhn. In that paper he noted that Limnobium Schimp. was an i l l e g a l homonym of Limnobium Rich. In that paper he attempted to transfer Hypnum b e s t i i Ren. et Bryhn to Hygrohypnum, but an e d i t o r i a l error prevented the transfer. In a footnote, Holzinger (1901a) stated "By typographical error i n the January issue, page 12 l a s t l i n e , Hygrohypnum b e s t i i (Ren. et Bryhn) Holz. was printed Hygrohypnum b e s t i i Ren. et Bryhn. The editor alone i s res-ponsible for t h i s . " Therefore, as noted by Lawton (1966) Holzinger should be given r i g h t f u l c r e d i t for the transfer. Hygrohypnum b e s t i i (Ren. et^ Bryhn) Holz. was described by Renauld £.1901) based on a Holzinger specimen from Avalanche Basin, Montana. The Renauld herbarium i s at PC. A search of the PC material has f a i l e d to produce any Holzinger specimens. At NY there i s a specimen bearing a l l the data indicated by Holzinger and ci t e d by Renauld. This specimen has been appropriately i d e n t i f i e d and i s designated as the lectotype. 158 Fig. 36 a - e. Variation i n the habit of the shoots of Hygrohypnum  b e s t i i and a comparison of individual shoots i n the moist and • iV'V- dry conditions. a. Moist; b. Dry c. A moist shoot with secund leaves d. Moist; e. Dry Scale: Each shoot i s approximately 2 cm long. 159 160 Fig. 37 a - i . V a r i a t i o n i n t h e l e a f s h a p e o f H y g r o h y p n u m b e s t i i . a - e. T h e t y p i c a l l e a f s h a p e . f - i . T h e l e a f s h a p e o f t h e l o w l a n d f o r m f r o m t h e P a c i f i c C o a s t of N o r t h A m e r i c a . S c a l e : I 2 m m I 161 162 Fi g . 38 a - i . C e l l u l a r d e t a i l of the foliage leaves of Hygrohypnum  b e s t i i . a - c. Leaf apices d. Median leaf c e l l s e - f. Marginal leaf c e l l s g - h. Alar c e l l s i . A l ar c e l l s from the lowland form from P a c i f i c Coastal North America. Scale: a - c, g - i : I 100um *" l d - f. | ' 100um l 164 Eig. 39. Hygrohypnum b e s t i i 165 Exs i c c a t i Examined Allen,. Mosses of the Cascade Mountains # 141 as H. dilatatum. (MICH, MIN, NY, USA) # 139a as H. ochraceum. (TENN, MIN) Grout, North American Musci Pleurocarpi # 251. (MIN, MO, NY, TENN, UC, USA) # 382 as H. molle. (MIN, MO, NY, TENN, UC, USA) Macoun, Canadian Mosses # 398 as H. arcticum. (MICH, MO, USA) Canadian Musci # 357 as H. dilatatum. (NY, USA) # 358 as H. arcticum. (MICH, MO, USA) # 360 as H. ochraceum. (MO) # 483 as Hypnum turgescens. (MICH, NY) Holzinger, Mosses of Nferth Western Montana # 56. (USA) # 62. (NY) Selected Specimens Examined Canada B r i t i s h Columbia Queen Charlotte Islands, Graham I., Mamin R. , Schofield 30054. (C, CAN, UBC) Queen Charlotte Islands, Moresby I., Takakia L.; Schofield 24991. (UBC) Manning Provincial Park, Windy Joe Mountain; Williams 329. (UBC) A t l i n , McKee Creek; Szczawinski 70/62. (USA) Garibaldi P r ovincial Park, Whistler Mountain s k i bowl: ' Jamieson 5480. (UBC) Bulkley Range: Boas 629. (UBC) New Denver, Denver Glacier; MacPadden 13 Sept 1925. (UBC) Roger's Pass, Selkirk Mountains; Macoun 2 Aug 1890. (UBC) Vancouver Island, Burmah L.; Boas 254. (UBC) Pasulko Lake, N. of Lyttoh; .Schofield 17936. (UBC) Prince Rupert, Slopes of Hays Mountain; Schofield & Sharp 11 Sept 1964. (TENN) Vancouver, Poiftt Grey; Schofield 13198. (CANM, UBC as Hygro-hypnum ochraceum. Lowland form.) West Vancouver, Lynn Canyon; Schofield 13347. (CAN, UBC) Vancouver I., Bear Creek, San Juan R,; Boas 25. (CAN, UBC) Saltspring I; Weston L.; Boas 424. (CAN, UBC) Alberta Kicking Horse Pass, Kicking Horse L.; Macoun Aug. 1890 as Canadian Musci # 483. (NY) Waterton Lakes National Park, divide on E. side of Cameron L.; Bird 6353. (NY) Oldman River Watershed, Race Horse Creek; Bird and Lakusta 18227. (CAN, UACA) Quebec Gaspe Sud, Gaspe Bay near Peno^ille; Crum and Williams 10798. (UBC) Gaspe Nord, Ruisseau-a-Rebours; Crum & Williams 10747 as H. dilatatum. (UBC) 166 Gaspe Co., St. Joachim de l a Tourelle; V i c t o r i n et a l . (MICH) New Brunswick Albert Co., Alma; Habeeb 1640 as H. molle v a r . b e s t i i . (NY) V i c t o r i a Co., Grand F a l l s ; Habeeb 918. (In the l i t e r a t u r e Habeeb 1952) Nova Scotia Cape Breton Highlands National Park, Beulach Ban F a l l s j Ireland 11845 as H. dilatatum. (UBC) Cape Breton Highlands National Park, Aspy R.; Schofield 4890 as H. dilatatum. (CANM) United States Alaska. Denali Highway, NW of Paxson, Hermann 21225. (CANM,MICH) kodiak Is. Group, Raspberry I,, Port V i t a ; Eyerdam 880 as H. molle. (TENN) Aleutian I s . , Attu I s . , Massacre Bay; Howard 51 as H, i. dilatatum. (TENN) Skagway; Williams 27 Aug 1899 as H. b e s t i i (NY) Anchorage, F i r e Lake; Lepage 22312 „ (S-PA) Aleutian I s . , Amchitka I s . , W. of Banjo Pt.; Shacklette 7621 t (MICH) Unalaska ; Setchell 28, (UC) Washington Olympic Mountains; Piper Oct. 1890 as L. dilatatum. (NY) Mt. Ranier, Goat Mountain; A l l e n 24 Sept 1898 as H. dilatatum (UBC) Scenic; Frye 3222. (NY) King Co., 2 mi. N, of Cedar F a l l s ; Ireland 5817 (WTU as Hygro-hypnum dilatatum. Lowland form.) Oregon Hood R, Co., Mt, Hood, Timberline Lodge; Hale 21576 as H, molle. (UBC) Klamath Co., Crater Lake National Park, Kerr Notch; Hermann 22873 as H. b e s t i i . (CSNM) Multnomah Co., Cloud Cap Inn; Schofield 19668 as H. dilatatum. (CANM) Region of the Alsea (a r i v e r ) ; Van Wert May 1923 as H. dilatatum. (MIN) Benton Co., Oak Creek Lab Oregon St. Univ., Hughes. (UBC, lowland form) C a l i f o r n i a Tehama Co., Bridge 8 - 69 on Deer Creek, Highway 32; Kowalski 4 May 1970 as H. molle. (CANM) Plumas Co., Indian F a l l s on fhdtan Creek, Route 89; Lawton 3136 as H. molle. (UBC) Fresno Co., Sequoia National Park, Stoney Creek; MacFadden 8 July 1959 as H. molle. (C§NM) Del Norte Co. G r i f f i n g Creek at Smith River, Highway 199; Norris 8849. (HSC) Siskiyou Co., Salmon R. near Big Bar; Norris 9280. (HSC) Modoc Co., Soup Creek Campground E, of Likel y ; Norris 9451. (HSC) 167 Calavaras Co., Bolander (USA) Shasta Co. Lassen National Park, Dersch Meadows? Mueller 6739. (UC) San Bernadino Co., Parrish 3884. as IH. pseudo-arcticum. (NY, UBC) Marin Co., Muir Woods National Mon,; Hermann 17477 (USA, lowland form) Humboldt Co., Praire Creek, Redwoods State Park; Jamieson 0099. (HSC, lowland form) Idaho Elmore Co. Boise National Forest, Hwy between Atlanta and Queen*sVR.; MacFadden 18706 as H. molle. (UBC) Idaho Co., 80 mi. ENE of Kooskis along route 12; Hermann 20210. (UBC) Lake Pend d'Orielle, Creek near Blueslide; Leiberg 1891. (NY) Montana Flathead Co., V i c i n i t y of Lake McDonald, Avalanche Basinj Holzinger & Blake 28 - 29 July 1898 as Hypnum turgescens i n Mosses of North Western Montana # 62. (NY) Carbon Co., Red Lodge, Bench Creek Picnic Area; Conard 27 Aug. 1953 as H. b e s t i i . (NY) Lake Co. Flathead Lake, Station Creek; Schofield 12189 as H. dilatatum. (UBC) WVoming Yellowstone National Park, Black Sand Basin; Lawton 1871 as H. molle. (CANM) Teton Co., Cascade Canyon; Conard 14 Aug. 1953 as H. b e s t i i . (CANM) Fremont Co., To-Gwo-Tee Pass; Porter 1619 as H. molle. (TENN) Albany Co., Centennial H i l l s ; Nelson 2804, as H. s m i t h i i (TENN) Colorado P i t k i n Co., S. of Redstone, route 133, Crystal R.-Hays C; Hermann 25635 as H. molle. (UBC) Boulder Co., Left Hand Creek; Prettyman 25 Feb 1960. (COLO) Mineral Co. San Juan Mtns., NE of Pagosa Springs; Hermann 23340. (COLO) Jackson Co., Mt. Z i r k e l Wilderness, Lone Pine Creek T r a i l ; Hermann 26740. as H. b e s t i i . (UBC) Grand Co., 1/2 mi S. of Rolling Pass; Hermann 25660. (WTU) Larimer Co., Rocky Mountain National Park, M i l l Creek; Hermann 25996. (WTU) Garfield Co., 31 mi. S. of G&enwood Springs, SW of Trappers Lake; Hermann 24258. (WTU) Clear Creek Co., 6 mi. SW of S i l v e r Plume, Quale Creek; Hermann 24918. (WTU) New Mexico Rio Arriba Co., V i c i n i t y of Brazos Canyon; Stanley S Bollman 10712 as H. dilatatum. (USA) South Dakota Lawrence Co. Eleven miles SW of Lead; Hermann 25360. (WTU) Michigan Keweenaw Co., Hebard Park; Steere Sept 1936 as H, molle (MICH) Ontonagon Co., Shores of Lake Superior? Nichols & Steeee 20 - 27 Aug. 1935 as H. molle. (MICH) 168 Utah Brookbark, C i t y Creek; Flowers 7165 as H. ochraceum. (DUKE) 169 Hygrohypnum cochlearifolium (Vent, in De Not.) Broth., Nat. P f l . ,1(3): 1 0 3 9 . 1909. Lectotype: Erbar. C r i t t . I t a l . , ser. 2, fasc. 10, n. 453. (NY) • Limnobium cochlearifolium Vent, in De.Not., Erbar. C r i t t . I t a l . , ser. 2, fasc. 10, n 453. 1871. (Lectotype NY) Limnobium cochlearifolium Vent, in De Not. & Bagl., Erbar. C r i t t . I t a l . , ser. 2, fasc. 9 - 11., no. 401 - 550. Genoa. 1871. Hedwigia (5):70 - 73. 1872. Hypnum goulardii Schimp., Syn 2:778. 1876. (Holotype BM) also in Rev. Bryol. 3(1):25 - 26. 1876. Hypnum cochlearifolium (Vent.) Vent., Rev. Bryol. 6(4):62. 1879: Hypnum arcticum ssp. goulardii (Schimp.) Ren., Rev. Bryol. 10:51. 1883. Hypnum arcticum var. goulardii (Schimp.) Husn., Muse. Gall. 414. 1894.. Calliergon goulardii (Schimp.) Kindb., Canad. Rec. Sci. 1894. 72. 1894. Limnobium goulardii (Schimp.) Roth, Die.Eur. Laubm. 2:640. 1905. Hygrohypnum goulardii (Schimp.) Loesk., Verh. Bot. Ver. Prov. 46: 198. 1905. Hygrohypnum smithii var. cochlearifolium (Vent.) Monk., Laubm. Eur. 741. 168b. 1927. Hygrohypnum smithii var. goulardii (Schimp.) Wijk et Marg. Ind. Muse. 5:577. 1969. Names of dubious or otherwise unclear status Hypnum cochlearifolium Vent., Known only from Index Muse. 3:39. 1964. "Limnobium cochlearifolium Vent.", Known only from the above source. 170 Names treated as synonyms i n other p u b l i c a t i o n s , but whose o r i g i n a l l i t e r a t u r e was unavailable during t h i s study. Amblystegium cochlearifolium (Vent. et_Bott.) Linb, i n Bomanss et Broth., Herb. Mus. Genn. ed. 2, 2:66. 1894. Amblystegium g o u l a r d i i (Schimp.) C. Jenns., Medd. Groenland. 15:433. 1898. Plants very s o f t , forming loosely woven, e a s i l y fragmenting, often mud-clogged patches or small, t i g h t l y woven patches. Color v a r i a b l e , d u l l , d i r t y green to yellow, usually yellow to yellow-green with conspicuous rusty mottling. Stems (1) 2 - 3 (5) cm long. Mostly unbranched or i n f r e -quently and i r r e g u l a r l y branched, branches e i t h e r large and of s i m i l a r s i z e to the stems and a r i s i n g from near the stem bases, or branches slender and short, seldom exceeding 1 cm, a r i s i n g i r r e g u l a r l y along the stems, a l l branches e i t h e r prostrate or ascending. Stem cross sections with 1 to 2 rows (sometimes a t h i r d more or l e s s incomplete row) of small, thick-walled, brownish c o r t i c a l c e l l s ; medullary c e l l s l a r ger and mostly thinner walled, hyaline or becoming brownish with age; c e n t r a l strand small, poorly d i f f e r -entiated. Plants eradiculose. Leaves v a r i a b l e , Crowded to very d i s t a n t . Leaf a t t i t u d e upon the stem varying from the wet to dry condition; when moist the leaves may be loosely imbricated to spreading and tumid; a t t i t u d e more variable upon drying, e i t h e r changing l i t t l e from the wet condition or v i s i b l y shrinking, leaves near the stem t i p s of very large plants frequently e x h i b i t considerable l a t e r a l shrink-age, though l i t t l e other c r i s p i n g , i n smaller plants the leaves r e t a i n t h e i r concavity upon drying. Leaves (0.5) 0.8 - 1.2 (1.5) mm long X (0.3) 0.6 - 1.0 (1.3) mm wide; shape usually oblong or o b l o n g - e l l i p t i c , sometimes o r b i c u l a r ; apex usually obtuse or rounded, occasionally acute, r e g u l a r l y cucullate; margins e n t i r e , variously recurved, p a r t i c u l a r l y i n the smaller leaves, or plane, e s p e c i a l l y i n larger leaves; concavity c l e a r l y evident throughout the species, very deep to cochleariform, p l i c a e present throughout, i r r e g u l a r in.inumber and arrangement; costa v a r i a b l e , usually short and double with one arm sometimes reaching midleaf, less often short and s i n g l e , s i n g l e to midleaf or absent, i n a l l cases the costa i s slender; leaves sometimes narrowly decurrent at the point of i n s e r t i o n . A r e o l a t i o n v a r i a b l e ; median l e a f c e l l s short fusiform, short l i n e a r flexose or rhombic, 26 - 48 (55) um long X (4) 5 - 6 (8) um wide; c e l l s becoming s l i g h t l y shorter and more rhombic toward the apex; changing l i t t l e toward the margin; marginal l e a f c e l l s short, l e s s than 50 um; basal c e l l s v a r i a b l e , gradually becoming s l i g h t l y longer and wider or changing l i t t l e ; p i t s few to none; a l a r c e l l s t h i n walled, undifferentiated or of a few quadrate or short rectangular c e l l s , never forming a c l e a r l y defined group. Sexuality poorly understood, plants usually s t e r i l e , P e r i g o n i a l d e t a i l unknown. Outer and middle p e r i c h a e t i a l leaves t r i a n g u l a r lanceolate, costa short and s i n g l e , margins recurved, s l i g h t l y squarrose reflexed i n the upper h a l f . Inner p e r i c h a e t i a l leaves oblong lanceolate, up to 2.5 mm long, erect apex mostly acute, e i t h e r e n t i r e or f a i n t l y denticulate, a few p a p i l l a e on the abaxial l e a f surface, margins recurved; Costa s i n g l e , fading above midle Seta yellowish to reddish-brown; 12 to 16 mm long, smooth; Capsule as i n the genus; Spores immature, unmeasurable. Peristome as i n the genus, annulus present, of two c e l l rows, endostome with 2 to 3 c i l i a . This p l a n t exhibits several features which, i n combination, may serve to d i s t i n g u i s h the taxon. The leaves are broadly ovate, oblong-ovate or or b i c u l a r . No other taxon i n the genus has such deeply concave leaves. In 172 some specimens the concavity may be as deep as 3/4 of the length of the l e a f . The species i s exceedingly s o f t . There i s no r i g i d i t y whatever to the moist stems. I t i s rare that patches of these plants do not e x h i b i t conspicuous rusty mottling or variegation over a p r i m a r i l y yellow or yellow-green c o l o r a t i o n . Certain characters within t h i s taxon e x h i b i t v a r i a t i o n that warrants discussion. The v a r i e t y varies i n o v e r a l l s i z e , l e a f shape, shape of the apex, recurvature of the l e a f margin, a t t i t u d e of the leaves upon the stem or branches, and the spacing of the leaves along the stem. In smalleriplants i . e . those with short stems, the small leaves are crowded and c l o s e l y appressed-imbricated. The concavity of the leaves imparts a julaceous aspect to the stems. The leaves are r e g u l a r l y recurved along the margin. In l a r g e r plants, i . e . , those whose stems vary from 3 to 4 cm long, the leaves are more d i s -t a n t l y spaced, often exceedingly concave and more or less erect-spreading to sometimes almost erect when moist. In these large plants the leaves i n the older portions of the stems w i l l be crowded and rather julaceous, whereas younger leaves, though of equal s i z e , w i l l be d i s t a n t and more spreading. Both Venturi i n De Notaris :(1871, 1872) and Schimper (1876) noted the narrowly recurved l e a f margins. Nyholm (1965) also remarked upon t h i s char-acter i n d i s t i n g u i s h i n g the v a r i e t y from Hygrohypnum norvegicum. This feature i s v a r i a b l e . Among small plants the margin i s r e g u l a r l y and conspicuously recurved (Fig. 40 h - k). In larger plants the margin i s recurved (Fig. 40 a - e) or plane (Fig. 40 f ) . In those leaves with plane margins the l e a f looks v i r t u a l l y l i k e a spoon. These plants vary considerably i n the placement of the leaves along the stems and branches. In some specimens they may be crowded, while i n others they are so widely spaced as to barely overlap. 173 The leaves of Hygrohypnum cochlearifolium are often irregularly plicate. However these plicae are not a clearly integral part of the leaves as are the plicae of the perichaetial leaves. Instead, they appear to be a function of the extremely flaccid nature of the leaves and their corresponding inability to resist the various physical pressures of water or the s o i l and sand particles that accumulate in the leaf concavity. The plicae are generally more frequent among the larger leaves, perhaps as a result of more exposed surface area. Generally leaves that have been thoroughly cleaned during examination have few i f any plicae. The sexual condition of Hygrohypnum cochlearifolium is unclear. Most authors have described i t as monoicous. Only Kindberg (1897) has said i t i s dioicous. The species is most frequently s t e r i l e . Only one plant bearing perigonia has been examined. The plants may be monoicous and very infre-quently sexual or i t may be clearly dioicous. This matter has yet to be resolved. The nomenclature of Hygrohypnum cochlearifolium (Vent.; in De Not.) Broth, is highly confused. This species was originally described very clearly by Venturi as Limnobium cochlearifolium in De Notaris' Erbar. Cirittog. I t a l . Ser. II n. 453 in 1871. The label of this exsiccatum bears a complete description and a reference to a collecting site. The only specimen of this important exsiccati available to me is at NY, where i t is f i l e d with Hygrohypnum smithii. The rules of nomenclature indicate that on or after 1 January 1953 only descriptive material distributed independent of an exsiccati may effect valid publication. The 1871 date of issue is well within the limit. Further, De Notaris and Baglietto (1872) published the label of the exsiccati. Index Muscorum, vol 3 cites the name Hygrohypnum cochlearifolium De Not., 174 Erbar. C r i t t . I t a l . ser. 2, 10:n. 453. 1871 as nom. nud. i n synon. Index Muscorum further indicates t h i s name to be synonomous with "Liimobium  cochlearifolium Vent.", an obvious miss p e l l i n g , which i s i n turn held as synonympjUS with Hygrohypnum s m i t h i i (Sw.) Broth, var. g o u l a r d i i (Schimp.) Wijk et Marg. I t i s obvious that Limnobium cochlearifolium Vent, i n De Not. and Hypnum cochlearifolium De Not. are based on the same e x s i c c a t i . A ca r e f u l examination of the l a b e l borne on t h i s e x s i c c a t i c l e a r l y shows only the name Limnobium cochlearifolium. Nowhere on the l a b e l i s there an i n d i -cation of the use or the preference for the use of Hypnum instead of Limno- bium. Further confusion i s added by the f a c t that the basionym f o r Weymouthia  c o c h l e a r i f o l i a (Schweagr.) Dix. i s Hypnum cochlearfolium Schweagr., Spec. Muse. Suppl. 1(2):221. 88. 1816. Were the name Hypnum cochlearifolium De Not. a r e a l i t y , i t would s t i l l be a l a t t e r homonym of the e a r l i e r Schweag-richen name. Schimper (1876) described Hypnum g o u l a r d i i from material c o l l e c t e d by Goulard i n the Pyrenees. An examination of the Schimper type at BM reveals that i t unquestionably the same organism as Limnobium cochlearifolium Vent Venturi "(1879) clouded the issue, himself, by c i t i n g Hypnum c o c h l e a r i -forme as a synonym of "Hypnum gounodii Schimp." an obvious m i s s p e l l i n g of Hypnum g o u l a r d i i Schimp. This would seem to imply that Venturi looked upon his own plant as i d e n t i c a l to Schimper's l a t t e r named plant. I f i n t h i s act Venturi transferred h i s Limnobium cochlearifolium to Hypnum cochlearifolium as a new combination and a synonym of Hypnum g o u l a r d i i Schimp., then the new combination becomes an i l l e g a l homonym of Hypnum cochlearifolium Schwaegr. In 1884 Venturi and B o t t i n i reported Limnobium cochlearifolium for I t a l y . An unfortunate misinterpretation of the Venturi report by Van der Wijk and 175 Margadant (1969) treated Venturi and Bottini as the parenthetical authors of Hygrohypnum cochlearifolium as cited by Brotherus '(1909) and H_. smithii var. cochlearifolium of Monkemeyer (1927). Brotherus (1909) clearly referred his name to Limnobium cochlearifolium in Venturi's exsiccati. Monkemeyer (1927) also referred his name to Venturi. However, Monkemeyer curiously cited Venturi' s use of Hypnum. I- have not been able to trace Venturi's apparent use of the name Hypnum of his species. Confusing though this situation i s , Limnobium cochlearifolium Vent, in De Not. is the basionym for Hygrohypnum cochlearifolium (Vent, in De Not.) Broth. Various authors have treated Hygrohypnum cochlearifolium as a variety. (Husnot, 1894- Monkemeyer, 1927) or a subspecies (Renauld, 1883) of H_. smithii. However, neither these authors nor Boulay (1884) adequately c l a r i f i e d the similarities between the two taxa. Several features indicate that Hygrohypnum  cochlearifolium is a species clearly distinct from H. smithii. Hygrohypnum  cochlearifolium is exceedingly soft. No other taxon in the genus is as soft. Hygrohypnum smithii i s exceedingly s t i f f and ri g i d . Neither taxon exhibits any reciprocal tendency towards softness or r i g i d i t y . Both Hygrohypnum smithii and Hygrohypnum cochlearifolium have concave leaves. However, the leaf concav-ity of Hygrohypnum smithii is simply not comparable to the cochleariform.-con-cavity of H_. cochlearifolium The overall areolation of the two taxa is different. Associated with the rigi d nature of Hygrohypnum smithii is the incrassate nature of the leaf c e l l s . On the contrary, the leaves of Hygrohypnum cochlearifolium are very flaccid and correspondingly thin-walled. The basal cells of H. smithii are also incrassate and yellowish in color. The basal leaf cells of H. coch- learifolium are thinner-walled, sometimes lax and either hyaline or slightly brown in color. The costa of H_. smithii is usually thick, yellowish, single 176 and/or forked, although short and double costae are not infrequent. The stout nature of the costa imparts considerable r i g i d i t y to the leaves. On the other hand, the costa of Hygrohypnum cochlearifolium i s usually slender, f a i n t , short and double. The slender and f a i n t q u a l i t y of the costa no doubt influences the f l a c c i d nature of the leaves, The l e a f margins of Hygrohypnum s m i t h i i are always plane whereas those of H_. coch- l e a r i f o l i u m may be plane or recurved. Although the inner p e r i c h a e t i a l leaves of both species have recurved margins, the' apex of the inner p e r i c h a e t i a l leaves i s rounded, whereas that of H. cochlearifolium i s acute. For a comparison between Hygrohypnum cochlearifolium and H. norvegicum see the discussion under the l a t t e r species. 177 F i g . 40 a - m. V a r i a t i o n i n the l e a f shape and the habit of the moist shoots of Hygrohypnum coc h l e a r i f o l i u m . a - c , e - f , h - k . V a r i a t i o n i n l e a f shape. d. Leaf "c" as seen i n cross-section. Note the reflexed margins, g. Leaf " f " as seen i n cross-section. Note the plane margin. 1 - m. V a r i a t i o n i n the habit of the shoots. Scale: a - k; I 1 m m 1 1 - m; Both shoots are approximately 0.6 cm long. 178 179 F i g . 41 a - e. C e l l u l a r d e t a i l of the foliage leaves of Hygrohypnum  cochlearifolium. a. Leaf apex, b - c. Median leaf c e l l s , d - e. Alar c e l l s . Scale: a - c; I ' IQOum | d - e; I 100um ) \ 181 4 - • -Fig. 42. Hygrohypnum cochlearifolium 182 E x s i c c a t i Examined De Notaris, Erbar. C r i t t . I t a l . ser. 2, fasc. 10, n. 453 as Limnobium cochlearifolium. (NY, Lectotype) Institutium Botanicum nomine V. L. Komarovii Academiae Scientiarum URSS, Hepaticae et Musci URSS E x s i c c a t i # 48 as Hygrohypnum cochlearifolium. (CAN, LE, UBC) Lisowski, Bryotheca Polonica. Fasc. X, # 296. (BP, LE) Fasc. XXV, # 667. (BP. CAN) Fasc. XXIV, # 637 as H. viridulum (BP, CAN, LE) Fasc. XXIV # 638 (BP, CAN) Fasc. XV, # 418. (LE) Museo H i s t . Hatur. Vindoboneasi, Cryptggame e x s i c c a t i # 2895. (BP, UC, F) Selected Specimens Examined Canada Yukon, Haines Highway, Mile 100; Crum and Schofield 9637 as H. norvegicum. (CAN, MICH) Northwest T e r r i t o r i e s , B a f f i n Is., Cape Searle; Hale 17 - 18 Aug 1950 as H_. s m i t h i i var. g o u l a r d i i . (UBC) United States Alaska Brooks Range, Endicott Mtns; Steere 18115a as H_. cochlearifolium. (NY) Mt. McKinley National Park, Mt. E i e l s o n ; Weber & Vierck 10301 as H_. cochlearifolium. (CAN, NY,), DUKE) Montana E l e c t r i c Peak; Rydberg & Bessey 18 Aug. 1897 as L . . g o u l a r d i i . (NY) . Colorado Clear Creek Co., Mt. Evans; Vaarama & Evans 11 Oct. 1963. .((COLO) Greenland • Godhavn; Berggren 1870 as H. norvegicum. (NY, S-PA, P) Disco Is. Diskofjord, Kuanit; P o r s i l d 954 as H. cochlearifolium. (CANM) Svartenhuk Penn. Simiutap kua; Holmen 12350 as H_. cochlearifolium. (CAN) Scoresbyland, Mestevig; Holmen 18043 as H. cochlearifolium. (CANM) Nugssuag Penn., ,Nugssuag; Holmen 15577. (S-PA, LE) Martlek; Beggren 1870.- (S-PA) Hurry I n l e t ; Dusen 7 Aug. 1899. (H) Spitzbergen Advent Bay; Ber^gr.eri 1868 as H_. molle. (S-PA) Robbe Bay; Berggren 1868 as H. molle. (S^ -PA) Norway Tromso amt, Nordreisen Galslsovare; A r n e l l 23 Aug. 1893. as H_. g o u l a r d i i . (S-PA) F i l e j e l d ; Bryhn Aug. 1887 as H. g o u l a r d i i . (S-PA) Dovre rensis Foksjriko,* Bryhn Aug. 1906 as H. cochlearifolium. (S-PA) 183 Finmarken, T a l i r k , Jorgensen 27 July 1890 as H_. g o u l a r d i i . (S-PA, H, NY) Sweden Harjedalen, Storsrjo, Smith 10 Aug. 1914 as H. cochlearifolium. (S-PA) Lule Lappmark, Tarrekaisse, Nilsson 12 Aug. 1897 as H_. norvegicum. (S-PA) Lule Lappmark, Sarjekensis, Rapsdalen, Jensen & A r n e l l 31 July 1902 as A. cochlearifolium (S-PA, H) Torne Lappmark, Fsasirujaka J u k a j a r v i , Hulphers 18 July 1944 as H_. cochlearifolium (S-PA) Finland Karesuando, Smith & A r n e l l 14 Aug. 1939. (S-PA) Finska Lapm. Euontelis, K o t i l a i n e n 10 July 1920 as A. viridulum. (S-PA) • Prov. Le., Par O-Kahpeusvarri, Roivainen 352 as H. viridulum. (S-PA, UAC) Soviet Union Kola Pen., montes Chibiny, Schljakov 24 Aug. 1947. (UBC, CANM) J e n i s e i , Nischznje Tauguska, A r n e l l 13 July 1876 as A. viridulum. (S-PA) Switzerland V a l a i s , St. Bernard, Amann 19 July 1932 as H. cochlearifolium. (S-PA) V a l a i s , Mt. Mora, Culmann Aug. 1886 as H. g o u l a r d i i . (S-PA) Bern, Faulhorn, Culmann 16 Aug. 1885 as H. g o u l a r d i i . '(H) Au s t r i a T i r o l , Glungezer Nordseite, S c h i f f n e r 4 Sept. 1903. (S-PA) Karnten, F o l l a c h , B r e i d l e r 6 Aug. 1861 as H. g o u l a r d i i (S-PA, H) Steiermark, Schladming, B r e i d l e r 20 Aug. 1882 as H. cochlearifolium. (H) Salzburg, Sulzbachthal, B r e i d l e r 13 Aug. 1890 as K. g o u l a r d i i . (H) I t a l y T i r o l I t a l i a n o , Saent, Venturi, Erbar, C r i t t , I t a l . ser. 2 n. 453 as L. cochlearifolium. (NY) Spain G a l l i a merid. Maladetta, Goulard 187 3 as H_. g o u l a r d i i . (BM) Poland Montes T a t r i , Lisowski 1 Sept 1957 as H_. cochlearifolium and Bryotheca Polonica # 638. (CAN) Czechoslovakia Vysoke Tatry, Mlynica, Pilous 263 as H. cochlearifolium. (CAN) 184 Hygrohypnum norvegicum (Schimp.) Amann, FI. Mouss. Suisse 1:188 et -2: 358. 1912. Hypnum viridulum Hartm., Handb. F l . ed. 5:324. 1849. horn, i l l e g . (Holotype, S-PA) Limnobium norvegicum Schimp., B r y o l . Eur. 6:70. 576. 1853. Hypnum norvegicum (Schimp.) Schimp., Syn. 637. 1860. Amblystegium viridulum Lindb., Musci Scand. 33. 1879. Limnobium viridulum (Lindb.) Kindb., Canad. Rec. Sc. 6(2):74. 1894. C a l l i e r g o n viridulum (Lindb.) Kindb., Eur. N. Am. Bryin. 1:86. 1897. Hygrohypnum viridulum (Hartm.) Broth., Nat. P f l . 1(3):1039. 1909. Plants forming small, s o f t , loosely to t i g h t l y woven t u f t s or patches. Color usually shiny, pale yellow-green, occasionally becoming a l i g h t brown with age. Stems 1 to 3 cm long, usually less than 1.5 cm, prostrate or with the t i p s s l i g h t l y ascending.- Branching i r r e g u l a r , branches 1.0-1.2 (1.5) cm long, ascending. Stem cross-sections revealing 2 to 3 rows of small, t h i c k -walled, brownish c o r t i c a l c e l l s ; medullary c e l l s larger and thinner-walled; c e n t r a l strand present, often discolored. Rhizoids v a r i a b l e , red-brown, sparse, a r i s i n g from the base of ventral stem leaves. Leaves ovate, r a r e l y broadly ovate; (0.4) 0.5 - 0.8 (0.9') mm long X (0.2) 0.4 - 0.5 (0.6) mm wide; apex usually acute, occasionally obtuse i n the more broadly ovate leaves; sometimes the apex may be s l i g h t l y squarrose; margins e n t i r e , v a r i o u s l y plane or r a r e l y very narrowly recurved, recurvature v a r i a b l e , but never encluding the l e a f apex, recurvature may be confined to the lower 1/4 of the l e a f or may occur throughout the margin exclusive of the apex; leaves plane to shallowly, but c l e a r l y , concave; costa short'and double, one arm often reaching midleaf, very r a r e l y slender and si n g l e to j u s t above mid-185 l e a f . Leaf attitude upon the stem varying from the wet to dry conditions,-when wet the leaves are s t r a i g h t and loosely imbricated to loosely spreading, very r a r e l y they may be s l i g h t l y f a l c a t e ; when dry the leaves tend to become crisped, usually shrinking l a t e r a l l y and concomitantly i n r o l l i n g or twis t i n g . Areolation v a r i a b l e ; median l e a f c e l l s short rhombic, b a c i l l i f o r m , f u s i -form or l i n e a r flexuose, (16) 20 - 30 (48) mm long X 5 - 6 mm wide; c e l l s decreasing s l i g h t l y i n length toward the apex; marginal l e a f c e l l s always less than "50 um; basal c e l l s v a r i a b l e , gradually elongating and widening from the median c e l l s , or widening s l i g h t l y , but changing l i t t l e i n length, or changing l i t t l e i n length or width, hyaline or becoming s l i g h t l y golden-brown with age; p i t s few to none; a l a r c e l l s u n d i f f e r e n t i a t e d or forming a small i r r e g u l a r group of a few, quadrate to short rectangular, s l i g h t l y incrassate c e l l s , hyaline or becoming brown with age. Plants monoicous, Perigonia ovate; p e r i g o n i a l leaves ovate, 0.2 to 0.6 mm long, deeply concave imbricated, ecostate, margins e n t i r e . Outer and middle p e r i c h a e t i a l leaves ovate to ovate lanceolate, squarrose-reflexed i n the apex, ecostate to short single or short and double, margine e n t i r e . Inner p e r i c h a e t i a l leaves lanceolate, erect, up to 1.8 mm long, apex gradually tapering to a point or acute, costa v a r i a b l e s i n g l e and slender or double, reaching midleaf, 2 to 4 p l i c a e , c e l l s from the base to midleaf p i t t e d , margins en t i r e to very f i n e l y and i r r e g u l a r l y toothed. Seta 6 to 10 mm long, yellow to reddish-brown, smooth-walled, s t r a i g h t or s l i g h t l y curved when wet, variously twisting and contorting upon drying. Capsule as i n the genus. Peristome as i n the genus. Annulus of two c e l l rows. Spores dark, dusky-yellow, 9 to 17 um i n diameter. Endostome with 2 to 3 well developed c i l i a , often f a l l i n g away. 186 In s p i t e of a monographic study, Hygrohypnum norvegicum remains a poorly understood species. There, are j u s t too few specimens of t h i s taxon from which to generate a sound concept of i t s v a r i a b i l i t y . In combination, four characters may serve to d i s t i n g u i s h Hygrohypnum  norvegicum. These characters are the very t i n y l e a f s i z e , the ovate l e a f shape, the acute l e a f apex and the loosely spreading nature of the moist leaves. In h i s o r i g i n a l d e s c r i p t i o n Schimper (1853) remarked upon the s i m i l a r -i t i e s and differences between L. norvegicum and what i s now known as Hygro- hypnum luridum. Later, he (Schimper, 1876) noted the s i m i l a r i t y of H. norveg- icum and H^ molle, as did Limpricht (1904) . From the present studies i t seems e n t i r e l y u n l i k e l y that H_. norvegicum could be confused with e i t h e r H_. luridum or H. molle. The following chart: may serve to c l a r i f y the s i t u a t i o n . H. norvegicum H. molle H_. luridum Leaf Length 0.4 to 0.9 mm 0.9 to 2.0 mil 0.9 to 2.5 mm Leaf Apex Acute Acute and blunt Gradually taper-ing to a point. Leaf Apex Margin E n t i r e Denticulate or E n t i r e e n t i r e Leaf Margins Plane to variously Plane Plane to i n r o l l i n g recurved i n the upper 1/2.' A l a r c e l l s U n differentiated or Undifferentiated Well-developed small group of quad- group of quadrate rate to short rec- to; short rectan-tangular c e l l s . u l a r c e l l s . The very smallest leaves of H^ luridum may overlap i n si z e with the very l a r g e s t leaves of H_. norvegicum. However, the differences mentioned above w i l l c l e a r l y separate them. ' 187 In Europe and North America l e a f length may be used as a general c r i t e r i o n f o r d i s t i n g u i s h i n g Hygrohypnum molle from H. norvegicum. In Europe the average l e a f length f or H_. molle i s 1.2 to 1.7 mm and very few leaves have ever been observed e x h i b i t i n g shorter lengths. In Western North America the average l e a f length for H_. molle i s 0.9 to 1.3 mm and i t i s , therefore, understandable that various reports of H_. norvegicum from south of 60°N. have been based upon misdeterminations of H_. molle. The specimen of H_. norvegicum, which e f f e c t s the remarkable d i s j u n c t i o n of the species from Alaska into southern B r i t i s h Columbia, c l e a r l y d i f f e r s from H. molle by i t s e n t i r e , recurved l e a f margins and i t s very short leaves (0.7' mm) . The s p e c i f i c l i m i t s between Hygrohypnum norvegicum and H_. cochlearifolium are weak. Both taxa tend to merge as a consequence of s i m i l a r patterns of v a r i a t i o n i n l e a f dimensions, l e a f concavity, l e a f marginal recurvature and the nature of the l e a f apex. The following chart w i l l point out the general d i f f e r -ences . Leaf Length Leaf Shape Leaf Apex Leaf concavity Leaf margins H_. norvegicum 0.4 to 0.9 mm Ovate Acute Plane to Shallow Plane to recurved H_. cochlearifolium 0.8 to 1.5 mm Broadly ovate to almost o r b i c u l a r Obtuse Deeply concave to coch-leariform Recurved to plane The leaves of H_. norvegicum are generally loosely imbricated to s l i g h t l y spreading. The leaves of H. cochlearifolium may also be loosely imbricated, but i n very small specimens, which are most r e a d i l y confused with H. norvegicum, 188 the deep l e a f concavity imparts a d i s t i n c t l y tumid appearance to the plants. The l e a f apices of H_. norvegicum are almost always acute. The l e a f apices of H_. cochlearifolium are generally obtuse, but.in small spec-imens c e r t a i n l e a f apices may be acute. Schimper (1853) described Limnobium norvegicum based on a B l y t t specimen from Gulbrandsdalen, Norway. Nyholm (1965) off e r e d two sets of i l l u s t r a -tions of H. norvegicum, one of which was ascribed to the B l y t t type. In personal communications Nyholm remembered that the B l y t t specimen was i n the Schimper c o l l e c t i o n at BM. A thorough search of the BM material has not yielded the B l y t t specimen. Hartmann (1849) described Hypnum viridulum. Hartmann's species i s the same taxon as Limnobium norvegicum, however, i t i s a l a t e r homonym of Hypnum viridulum B r i d . The Hartmann type, at S-PA i s a Holmgren specimen from Sarkevare, Lule Lappmark, Sweden. The second set of i l l u s t r a t i o n s c i t e d by Nyholm (1965) for Hygrohypnum norvegicum was based on the Hartmann type. A c a r e f u l study of a l l the a v a i l a b l e descriptions and specimens has shown that I completely agree with Nyholm's treatment of the Scandanavian material. Based on my agreement with her work, I can only assume that she accurately assessed the c o n s p e c i f i c i t y of the Schimper and Hartmann types. I have accordingly based my concept of Hygrohypnum norvegicum on the Hartmann type. 189 F i g . 43 a - j . V a r i a t i o n i n the l e a f shape, the c e l l u l a r d e t a i l of the f o l i a g e leaves and the habit of the shoots of Hygrohypnum norvegicum. a - d. Leaf shape e - f. The habit of the moist shoots. g - h. Leaf a p i c i e s i . A lar c e l l s j . Median l e a f c e l l s Scale: a - e ; I 0.5mm 1 e - f; Both shoots are approximately 0.5 cm long. a _ I ' 100um I 1 9 0 191 -I-F i g . 44- Hygrohypnum norvegicum 192 Selected Specimens Examined Canada B r i t i s h Columbia Salmo area, Porcupine Greek; Jamieson # 5598. (UBC) United States Alaska Mt. McKinley National Park, t r a i l above Riley Creek; Croasdale B-23. (USA) Greenland Scoresby Sund, Rypefjord; Holmen 18767 as Hygrohypnum viridulum. (NY) Norway L i l l e E l v e d a l , Teadfaler laca Gronne Grotto; Kaurin Aug. 1892 as Hypnum viridulum. (S-PA)-L i l l e E l v e d a l , prope F l a d f a t e r , "Gronne Grotto"; Kaurin Aug. 1888 as Hypnum viridulum. (S-PA) Dovre, Knudshoe; Bryhn Aug. 1887. (S-PA) Dovre, Zetterstedt 11 July 1854. (C, S-PA)-L i l l e Elevedal, Gronne Grotto; Kaurin Aug. 1887. (S-PA) Sweden Norbotten, Overtornea; Lonnqvist 22 Aug. 1963 as Hygrohypnum nor- vegicum. (S-PA) Jamtland, Undersakers s;n Sylarna; Krusenstjerna 12 July 1938 as Hypnum viridulum. (S-PA) P i t e Lappmark, Arjeplog sn, L u l . Istjakk; Wistrand 2 July 1936 as Hypnum viridulum. (S-PA) Lulea Lappmark, Sarkavaare; Holmgren June 1848, c i t e d as Amblysteg- ium viridulum.- (Holotype f or Hypnum viridulum, S-PA) Lulea Lappmark, St. S j o f a l l e t ; Holmgren 9 July 1867. (S-PA) Lapponia Lulensis, Sareks; Jensen & A r n e l l 3 Aug. 1902 as Ambly- stegium viridulum. (C, S-PA) Finland Lapp. ov., In alpe Schelesnaja prope pagu Kantalaks; Brotherus 29 July 1872. (H-SOL) Au s t r i a Steiermark, Schladming; B r e i d l e r 27 Aug. 1869 as Limnobium sp. (BP) 193 Hygrohypnum molle (Hedw.) Loesk., Moosfl. Harz. 320. 1903.. Neotype: Scotland, Ben Mac Dhui, by streamlets from perpetual snow: G.-.-Ei Hunt, July 1871. (S-PA) Hypnum molle Hedw., .Spec. Muse. 273. • 70f. 7 - 1 0 . 1801. Hypnum rupestre Schleich. ex Spreng. Mant. Prim. FI. Halens. 56. 1807. Hypnum molle var. rigidulum Hartm., Handb. Skand. FI. ed. 5:324. 1849. nom. i l l e g . i n c l . type spec. Limnobium molle Schimp., Bryol. eur. 6:69. 576. 577. 1853. Hypnum molle var. giganteum Lor., Verh. Zoo. Bot. Ges. Wien 13: 1331. 1863.- nom. nud. Hypnum Schimpefianum Lor., Moostud. 123. 5c. 1864. (Holotype, G) Hypnum taurense Mol. i n Lor., Moostud. 123. 1864. nom. nud. i n synon. Hypnum alpestre var. turgescens Lor., Moostud. 123. 1864. nom. nud. i n synon. Hypnum molle var. schimperianum (Lor.) Schimp., Syn. ed. 2:775. 1876. Hypnum molle var. schimperi Lindb., Bot. Not., 1877:30. 1877. Amblystegium molle (Hedw.) Lindb., Musci Skand. 33. 1879. Amblystegium molle var. schimperianum (Lor.) Lindb., Musci Skand.-33. 1879. Hypnum dilatatum ssp. molle (Hedw.) Ren., Rev. Bryol. 10:51. 1883. Hypnum molle var. maximum Boul., Muscin. France 24. 1884. Limnobium submolle Kindb., Rev. Bryol. 22:87. 1895. Ca l l i e r g o n submolle (Kindb.)Kindb.,' Bot. Not. 1896:132. 1896. Ca l l i e r g o n molle (Hedw.) Kindb., Eur. N. Am. Bryin. 1:84. 1897. Hypnum molle var. pyreniacum Ren., B u l l . Act..Int. Ge©gr. Bot. 10:8. 1901. 194 Hypnum b e s t i i var. pyreniacum (Ren.) Ren., Rev. B r y o l . 28:8. 1901. Hygrohypnum molle var. schimperianum (Lor.) Loesk., Hedwigia 49:52. 1909.-Hygrohypnum molle var. pyreniacum (Ren.) Podp., Consp. 576. 1954. Plants s o f t , i n loosely to t i g h t l y woven mats or patches. Color v a r i a b l e , b r i g h t yellow-green, olive-green, yellow-green or golden v a r i e -gated yellow-green above, yellow-brown, golden-brown or brown below, usually yellowish-green, olive-green, occasionally bright-green throughout; stems (1) 3 - 7 (10) cm long, procumbent. Branches i r r e g u l a r , very widely spaced, often a t t a i n i n g the length of the main stem, e s p e c i a l l y within r a d i a l l y symmetrical patches, or branches short and ascending from prostrate stems. Stems usually l e a f y throughout, infrequently the lower 1 or 2 cm of o l d stems may be denuded. Stem cross-sections with 2 to 3 rows, occasionally and i n -complete fourth rows, of yellow to reddish-brown, small, thick-walled c o r t i c a l c e l l s ; medullary c e l l s l arger, thinner-walled though sometimes becoming in c r a s s -ate and d i s c o l o r e d with age; c e n t r a l strand weakly to strongly d i f f e r e n t i a t e d , often d i s c o l o r e d . Rhizoids red to reddish-brown, a r i s i n g from the base of v e n t r a l stem leaves, but of i r r e g u l a r occurrence. Leaves v a r i a b l e ; c l o s e l y spaced to d i s t a n t , e s p e c i a l l y on young branch-t i p s . Attitude on the stem l i t t l e d i f f e r e n t from the wet to the dry condition; loosely imbricate or s l i g h t l y spreading., Leaves s t r a i g h t , r a r e l y s l i g h t l y secund, young branch leaves sometimes s l i g h t e d twisted at the apex when dry. Leaves broadly ovate, r a r e l y ovate or almost o r b i c u l a r , generally tapering gradually to an acute, but blunt apex, (0.8) 1.0 - 1.75 (2.0) mm long X (0.6) -.75 - 1.2 (1.25) mm wide; margin v a r i a b l e , e n t i r e , undulate or f i n e l y 195 denticulate i n the upper h a l f , e s p e c i a l l y i n the apex, margins sometimes s l i g h t l y recurved at the i n s e r t i o n point; shallowly to deeply concave; narrowly or hardly at a l l decurrent; costa v a r i a b l e , usually short and double with slender arms, the longest arm reaching midleaf or s l i g h t l y beyond, or double with both arms reaching midleaf, r a r e l y single to midleaf and/or forked. Areolation rather uniform; Median l e a f c e l l s rhomboid to l i n e a r fusiform flexuose, thin-walled, (24) 32 - 52 (74) mm long X (3) 5 - 6 (8) mm wide, i t i s not uncommon for unusually long or short c e l l s to occur i n leaves with an otherwise long or short areolation; usually l i t t l e change from the median to the a p i c a l c e l l s , but i n some leaves the a p i c a l c e l l s become short rhombic, to short fusiform; marginal c e l l s i n the upper h a l f of the l e a f 15 to 60 um long, usually 30 to 50 um. c e l l s reaching 60 um are rare; basal c e l l s becom-ing longer or shorter, s l i g h t l y wider, s l i g h t l y more incrassate, p i t s few to none, discolored or not at a l l ; a l a r c e l l s u n d i f f e r e n t i a t e d or a few s l i g h t l y incrassate, unpitted quadrate to short rectangular c e l l s , hardly d i f f e r e n t from surrounding c e l l s , r a r e l y d i s c o l o r e d . Plants autoicous; p e r i g o n i a l leaves ovate with an-apiculate apex, deeply concave and ecostate; outer p e r i c h a e t i a l leaves ovate, tapering to an acute apex, up to 1.1 mm long, weakly short double costate; inner p e r i c h a e t i a l leaves l i n e a r lanceolate, 2.0 to 3.5 mm long, 2 to 4 long p l i c a e , costa absent, f a i n t and double, or s i n g l e to midleaf; apex acute or obtuse, c e r t a i n c e l l s on the abaxial surface of the l e a f apex bearing a few p a p i l l a e formed by o v e r r i d i n g d i s t a l endwalls. Seta 6 to 15 mm long, usually 7 to 11 mm, orangish-red, reddish-brown to deep maroon, smooth, s t r a i g h t when wet v a r i o u s l y , twisted when dry; Capsule as i n the genus; Annulus of 2 to 3 rows of deciduous c e l l s . 196 Peristome as i n the genus; Endostomal c i l i a rudimentary or wanting; Spores smoky brown, f i n e l y p a p i l l o s e , 12.5 to 18.7 um i n diameter, usually 14.6 to 16.6 um. Hygrohypnum molle can be distinguished from other species i n the genus by 1. the broadly ovate, concave leaves (Fig. 45 a & b), which generally taper into an acute, but blunt, and often denticulate apex (Fig. 46 a & b), 2. the u n d i f f e r e n t i a t e d a l a r c e l l s (Fig. 46 f & h) and 3. the inner p e r i -c h a e t i a l leaves i n which the c e l l s on the abaxial surface of the l e a f apex are p a p i l l o s e by means of overriding d i s t a l endwalls (Fig. 46 d). Hygrohypnum molle does e x h i b i t some v a r i a t i o n with respect to growth habit, l e a f shape and s i z e , toothing of the l e a f apex and l e a f concavity. Throughout Europe and i n some specimens from North America Hygrohypnum  molle forms loosely woven t u f t s or patches i n which the stems branch at i r r e g u l a r i n t e r v a l s and the branches quickly grow to lengths close to the lengths of the stems. On the other hand, most North American'specimens, e s p e c i a l l y those from Southern B r i t i s h Columbia and adjacent Washington, form t i g h t l y woven, but s o f t patches or mats i n which branching i s i r r e g u l a r and both branches and stems are short and more or less ascending. Leaf shape i s generally broadly ovate (Fig. 4 5 a & b). Certain specimens may e x h i b i t ovate (Fig. 45 c) or almost o r b i c u l a r leaves (Fig. 45 d & e). Leaf concavity i s usually more evident i n the more o r b i c u l a r leaves. Throughout the en t i r e range of Hygrohypnum molle the l e a f length varies more or less continuously from 0.8 to 2.0 mm. Lawton (1971) noted that leaves of North American plants were s l i g h t l y smaller than those of European specimens. The present study has borne out those observations. In Europe the average le a f length varies from 1.2 to 1.7 mm, whereas i n North America, and e s p e c i a l l y i n B r i t i s h Columbia and Washington, the average length i s 0.9 to 1.3 mm. The 197 very largest leaves from North American plants have not been observed to exceed 1.5 mm. The leaf apex is generally described as acute, but blunt and finely denticulate (Fig. 46 a)• However, i t may vary from acute to obtuse and coarsely denticulate to entire. Concavity seems to vary somewhat, relative to leaf shape. There is a tendency for large ovate leaves to be shallowly or not at a l l concave, whereas broadly ovate leaves are deeply concave. However, the correlation is not absolute. The costa i s generally short and double, however, i t may vary from double with one arm reaching midleaf or beyond, double with both arms reaching midleaf or beyond or single and/or forked to midleaf or beyond. The early works of Bridel ( 1 8 1 2 , 1 8 2 7 ) , Sprengel (1827) and Hampe (1837) noted a similarity between Hygrohypnum molle and H. alpestre. Further, Schimper.. (1853) illustrated H_. alpestre with a drawing of H. molle. Both of these species have straight, concave leaves that are loosely imbricated or with the shoots sometimes julaceous. At the apex of some stems and branches the young leaves are so crowded that the stem or branch apex appears obtuse. Though these characters reflect a common bond within the genus, they mask very fundamental differences at the species level. The following chart w i l l i l l u s t r a t e the important differences. 198 H. molle H. alpestre Leaf shape Leaf apex Concavity Alar cells Median leaf cells Inner perichae-t i a l leaves Broadly ovate Acute but blunt, plane Shallowly to deeply so Essentially undiffer-entiated. Usually 32 to' 52 um long Apex coarsely denticu-late and papillose Oblong or oblong lanceo-late . Apiculate and reflexed Deeply so, often quite boat shaped in the apex. Large group of quadrate cells Usually 65 to 90 um long Apex long tapering, entire, smooth. I l l founded concepts of Hygrohypnum molle and H_. duriusculum have long caused confusion between these two clear-cut taxa. The following chart w i l l perhaps clarify, the differences. Leaf Shape Alar cells Stem cross section Inner perichae-t i a l leaves H_. molle Broadly ovate, gradually tapering to an acute but blunt t i p . Undifferentiated 2 to 3 rows of small incrassate cortical cells Apical cells- papillose by distally overriding endwalls. H-. duriusculum Oblong-elliptic to broadly ovate, more abruptly tapered to an obtuse, broadly acute or apiculate apex. Well developed groups of quadrate, incrassate, discolored c e l l s . 3 to 4 rows of small, incrass-ate cortical c e l l s . Apical cells smooth Inner peristome Endostome smooth, c i l i a rudimentary. Endostome finely papillose with well developed c i l i a . 199 Hygrohypnum molle and H. cochlearifolium have a number of common features. Both plants are quite soft, although H. cochlearifolium is the softer of the two. The leaves of both are generally loosely imbricate to slightly spreading (Fig. 45 f & g with Fig. 40 1). The leaves of H. molle are generally broadly ovate and shallowly concave, but certain spec-imens may exhibit broader leaves with a deeper concavity (Fig. 45 d & e) that are more comparable with H_. cochlearifolium (Fig. 13 d) . Both taxa frequently exhibit .a similar pattern of golden-brown mottled coloration. The costa morphology is similar and has already been pointed out in the discussion of H. cochlearifolium. The two taxa may be distinguished from one another by the following features: H. molle Leaf Shape Leaf Length Leaf Margins Leaf Apex Leaf Concavity Alar Cells Endostome Perichaetial Broadly ovate 0.8 to 2.0 mm Plane; denticulate to entire Gradually tapering to an acute but blunt point Shallow Undifferentiated H_. cochlearifolium Mostly oblong-elliptic to almost orbicular 0.5 to 1.5 mm Usually recurved, sometimes plane; entire or weakly crenulate Apex broadly rounded obtuse Very deep to cochleariform Undifferentiated or a few quadrate cells C i l i a 2 to 3 C i l i a rudimentary or wanting Apex coarsely denti- Apex entire; margins recurved; culate; margins plane; apical cells smooth, rarely apical cells papillose 1 or 2 papillae 200 As an autoicous species the presence of antheridia and archegonia on the same individual would theoretically enable H. molle to freely re-produce sexually. If the number of herbarium specimens bearing sporophytes is a reasonable measure of a species fecundity, then i t appears that Hygro-hypnum molle reproduces sexually very infrequently. Barely ten percent of the several hundred specimens studied bear sporophytes and the majority of f e r t i l e specimens are from Western North America. At the inception of this study four subspecific taxa were recognized for Hygrohypnum molle (Wijk et a l . , 1962). Hygrohypnum molle ssp. best i i (Reri. et Bryhn) Broth, is treated here as a species. Sakurai (1932) des-cribed H_. molle var. japonicum. Examination of the holotype from the Makino Herbarium has revealed that the plant i s only a form of Hygrohypnum ochraceum. Hygrohypnum molle var. pyreniacum (Ren.) Podp. was described by Renauld in two slightly varying descriptions in the Academe de Geographie Botanique Bulletin Vol. 10 and Revue Bryolbgique Vol. 28 in 1901. Renauld remarked upon.the similarity of the plant to Hypnum b e s t i i . A specimen whose label bears the data given by Renauld for the type specimen is at NY. It seems likely that this specimen is a duplicate of the type that Renauld may have sent to J. M. Holzinger. Examination of the plant reveals that i t is a mod-erately large specimen of H_. molle. It does not have the very long marginal leaf cells that would otherwise align i t with H. b e s t i i . Lorentz (1864) described Hypnum molle var. schimperianum. At G (Sheet 3079/247) there is a specimen agreeing with the collecting information indi-cated by Lorentz. A careful examination of this specimen reveals that i t is not sufficiently different from other specimens of Hygrohypnum molle to warrant taxonomic recognition. Although the principle of priority credits Hedwig.with the authorship of 201 Hygrohypnum molle (Hedw.) Loesk., i t is clear that he based his concept on Hypnum molle Dicks. Similarly, Schimper (1853) based his concept of Limnobium molle, in part, on Dickson's concept. The type locality as given by Hedwig (1801) is "ad rivulorum ripas in alpibus Scotius." Schimper (1876) narrowed the earlier heterogeneous concept of L. molle Schimp. by extracting Hypnum dilatatum and H_. alpinum. The more restrictive concept was again equated with that of Hypnum molle Dicks, and several specimens were cited as the basis for the concept. Among the specimens was one collected by G. E. Hunt from Ben Mac Dhui in Scotland. At S-PA there are two specimens bearing these data and both specimens are equally representative of the concept of Hygrohypnum molle as perceived in the present study. One problem in the typification of Hygrohypnum molle lies in the fact that the only specimen bearing the name Hypnum1; mo Me Dicks, in the Hedwig^ Schwaegrichen herbarium at G. is a mixture of Hygrohypnum luridum (Hedw.) Jenn. and H. duriusculum (De Not.) Jamieson. That a specimen is in the 'Hedr-wig herbarium does not necessarily mean that Hedwig ever saw i t . A comparison of the broadly ovate leaves of the troublesome specimen with Hedwig's type description of the leaves of Hypnum molle as " f o l i a ovato-lanceolata" and an examination of Tab. LXX clearly reveals a lack of agreement. Therefore, this anomalous specimen.from the Hedwig herbarium is rejected as representative of Hygrohypnum molle. In the absence of any Dickson material or appropriate Hedwig material and based on a'careful study of several hundred specimens bearing the names Hypnum  molle and H_. duriusculum I select the following specimen, to serve as the neo-type of Hygrohypnum molle (Hedw.) Loesk.: Scotland, Ben Mac Dhui, by streamlets from perpetual snow. Leg. G. E. Hunt, July 1871 202 ex herb. G. Stabler & ex herbario S. O. Lindberg. At S-PA. 203 Fig . 45 a - g. Variation i n the leaf shape and the habit of the shoots of Hygrohypnum molle. a - e. Foliage leaves, f - g. The habit of moist shoots. Scale: a - e; I 1mm I f; The shoot i s approximately 0.6 cm long g; The shoot i s approximately 2 cm long \ 204 46 a - h. C e l l u l a r d e t a i l of the foliage and p e r i c h a e t i a l leaves of Hygrohypnum molle. a - b. Foliage leaf apices c & e. Marginal leaf c e l l s d. P e r i c h a e t i a l leaf apex f S h. Alar c e l l s g. Median leaf c e l l s Scale: a - b; I 100um I c, e and g,- 1 • 100um I d, f and h; I 100um \ 206 207 4-Fig. 47 . Hygrohypnum molle 208 E x s i c c a t i Examined A l l e n , Mosses of the Cascade Mtns., Washington. # 142 as H. arcticum. (MIN, NY, TENN, USA, DUKE) Macoun, Canadian Mosses # 393 as H. pseudo-arcticum. (CANM) # 394 as H_. arcticum. (USA) # 398 as Hypnum arcticum. (LE) Bauer, 'Musci europaei e x s i c c a t i # 649 as Hygrohypnum schimperianum. (S-PA, BRNM) # 1663 as H_. molle var. schimperianum. (CANM, S-PA) Kerner, F l o r a Exsiccata Austro Hungarica # 1923 as Hypnum schimperianum. (BRNM, MIN, S-PA) # 1924. (BRNM, G, LE, MIN, MO, NY, UC, BP':, C) Lisowski, Bryotheca Pblonica Fasc. XV # 418 as H. viridulum. (CANM) Fasc. XV # 419. (CANM, LE) Fasc. XXV # 669. (CANM) Fasc. XXV # 668. (LE) Fasc. XXXI # 824. (CANM, NICH) Museo Hi s t Natur Vindobonensi, Cryptogamae e x s i c c a t i # 4260 as'H. molle. (G, LE, NY) # 4362 as H. molle. (G, LE) Museum Botanicum U n i v e r s i t a t i s C l u j , F l o r a Romaniae E x s i c c a t i # 1411 as H_. molle var. schimperianum. (MO, S-PA) Zmuda, Bryotheca Polonica # 150. (S-PA) Selected Specimens Examined Canada B r i t i s h Columbia st Mt. Seymour P r o v i n c i a l Park, 1 Punp Peak; Schofield 15968 as H. alpestre. (CANM) Ga r i b a l d i P r o v i n c i a l Park, Whistler Ski Bowl; Jamieson 5486. (UBC) Vancouver Island, Strathcona P r o v i n c i a l Park, Burman Lake; Boas 254. (UBC) Gold Ranges, Macoun 10 Aug. 1889 as H. pseudo-arcticum i n . Canadian Mosses # 393. (CANM) Rocky Mountains, Hector; Macoun 8 Aug. 1904 as H. arcticum i n Canadian Mosses # 398. (CANM) Eagle Pass Mtns., near Revelstoke; Taylor 21 Aug. 1921 as H. dilatatum. (MICH, USA) United States Washington Mt. Ranier National Park, Mt. Ranier; A l l e n 119^as H_. arcticum i n Mosses of the Cascade; Mtns., Washington # 142. (NY, TENN, USA, MIN) Oregon' Hood River Co., Cloud Capp Inn; Frye 29 Aug. 1907. (WTU) Mt. Hood; Roell 1140 & 1411. (NY) 209 C a l i f o r n i a Mono Co., H. M. H a l l Natural Area, Sp u l l e r Lake; Catchende 47138. (MICH) Eldorado Co., Echo Lake; Conard 5 Sept. 1947. (MICH) Montana Flathead Co., Sperry G l a c i e r T r a i l , Akaiyan F a l l s ; Hermann 20757. (NY, WTU) Colorado Larimer Co., Rocky Mountain National Park, Longs Peak: Kiener 4113. (CANM, MICH) Alaska Juneau I c e f i e l d , Taku Anunatak; Ward 8-27-49-28 as H. subeugyrium. (MIN) Great B r i t a i n Scotland Ben Mac Dhui; Fergusson July 1873. (S-PA) Ben Nevis; Boner 1870. (NY) Ben Nevis; i n the Red Burn; Dixon 11 July 1898. (NY) Norway Jotuukjeldene supra hosptium Gjendeboden; Kaurin Aug. 1891. (S'-PA) Finnmarken, aunt Tanen Burkelium; Kaurin July 1895. (s-PA) Norefjeld; Bryhn July 1900. (S-PA) Knudshoe; Bryhn Aug. 1885. (S-PA) Ef f e s vagen Vidasoeter G r o s l l i ; Jensen 1 July 1937. (S-PA) Opdal, i n monte Snehetta;. Olsson 31 July 1885. (LE, NY) Sweden Harkedalen, par Tannas; Einander 3 - 4 Aug. 1891. (S-PA) Jamtland, K a i l s sn L i l l a n j e s k u t a n ; Hakelier 13 July 1966. (S-PA) Brahnkyika; C l i v e 1857. (S-PA) Finland Lapp, r o s s i t . , Kipina; Angstrom. (S-PA) Lapponia imandrau, Umptek; Kihlman 30 July 1892. (S-PA) Kemi Lapp. K o l a r i ; K o t i l a i n e n 11 Aug. 1927. (S-PA) Lapponia murr., L i t s a ; Brotherus 3 June 1887. (NY) Soviet Union Lapponia murmanica, S i t s a , Kola; Brotherus Aug. 1887. (C, S-PA) Germany Matrei, Algau, Siegerlandhusse; Leg. ? 8 Aug. 1929. (BRNM, accesion number 08719) France Chamoix; Payot.1854. (G, 3079/210) Mt. Blanc; Leg. ?. (G, 3079/208). V a l l e de Barbarine, sur les Roches Seliceuses a Fontanabran; Bernet 13 Aout 1903. (G, 3079/259) Switzerland La F i b b i a , St. Gotthard; Weber 7 Aug. 1881. (G, 3079/228) Va l a i s , Grand St. Bernard, Combe 'des Morts; Rhodes 1705 as H. molle. (NY) ' A u s t r i a 1720/89 T i r o l , I n n e r v i l l g a r t e n ; Ganders 15 Sept. 1881. (B, —1972""^ 210 Sa l i s b u r g i a , Montes Lanschitzbar prope Lessach; B r e i d l e r as F l o r a Exsiccata Austro-Hungarica # 1924. (G, 3079/205) Steiermarkj^S,jngsdorfer; B r e i d l e r 25 July 1887. B ' . 1972 I t a l y Genoa, rupes Fonalis; Lorentz 12 Aug. 1864. (S-PA) Czechoslovakia Vysoke Tatry, Furkota; Smarda 3 July 1957. (BRNM) ' Poland Montes A l t i , v a l l e Dolina; Lisowski 27 Aug. 1956 as Bryotheca Polonica # 419. (CANM) Romania Transylvania, d i s t r . Hunedosra, In montes Retezal; P e t e r f i 24 July 1914 i n F l o r a Romaniae E x s i c c a t i # 1411. (S-PA). 211 Hygrohypnum styriacum (Limpr.) Loesk., Nat. P f l . 1(3):1039. 1909. Hypnum (Limnobium) styriacum Limp., Flo r a (Jena) 65:201. 1882. Eurhynchium (Pseudo-Rhyncostegium) styriacum (Limpr.) Kindb. Cad. Rec. S c i . 6:22. 1894. Limnobium styriacum (Limpr.) Roth, Eur. Laubm. 2:638. 56 f. 2. 1905. Names from the l i t e r a t u r e but not a v a i l a b l e for assessment. Hypnum stiriacum Limpr. ex. Par., Ind. B r y o l . Suppl. 213. 1900. nom, i l l e g . orthogr. pro H_. styriacum. Plants variously s o f t to s l i g h t l y r i g i d , i n loosely to t i g h t l y woven patches or mats. Color usually d u l l yellow-green with a rusty mottling, less often a d i r t y brownish yellow-green or a uniform d u l l green. Stems 1 - 4 (6) cm long; variously f o l i o s e , e i t h e r f o l i o s e throughout or denuded i n the lower portions, e s p e c i a l l y i n the very long stems; stems mostly pros-t r a t e , sometimes somewhat ascending. Branching i r r e g u l a r . Sparsely radicu-lose. Stem cross-sections revealing 2 to 3 rows of small, thick-walled cor-t i c a l c e l l s ; medullary c e l l s gradually becoming larger toward the middle, often becoming thicker-walled and d i s c o l o r e d with age; c e n t r a l strand well developed. Leaves v a r i o u s l y disposed along the stem, decidely d i s t a n t to s l i g h t l y crowded, crowding often more evident near the stem and branches a p i c i e s . Attitude variable from the wet to dry condition; when wet the leaves are spreading a l l around the stem, les s often s l i g h t l y f a l c a t e ; lipon drying the leaves shrink l a t e r a l l y to a marked degree, often concomitantly twisting i n various a t t i t u d e s , e i t h e r spreading, e s p e c i a l l y so i n smaller branches, spreading, weakly imbricated, p a r t i c u l a r l y near stem and branch apici e s or 212 f a l c a t e ; Leaf shape quite uniform, ovate with an abruptly or gradually acuminate apex, usually s t r a i g h t , or s l i g h t l y f a l c a t e , i n which case the apex usually tapers gradually; apex i s sometimes sharply reflexed; Leaves (0.7) 1.0 - 1.75 (2.0) mm long X (0.3) 0.5 - 1.0 )1.1) mm wide;,.margins e n t i r e ; conspicuously broadly concave when wet; very weakly decurrent or • not at a l l ; c o r t i c a l stem c e l l s often adhere to the l e a f base; costa strong and thick, short'and double, si n g l e and/or forked, or infrequently s i n g l e to above the middle. Areolation quite uniform, median c e l l s generally short, variously rhombic, short fusiform or b a c i l l i f o r m ; thick-walled (18) 28 - 40 (50) um long X (4) 5 - 7 (9) um wide; l i t t l e changed toward the apex; c e l l s varying toward the base, those c e l l s nearer the costa becoming longer and narrower toward the base, those c e l l s near the margin becoming shorter and broader, these tendencies are general, however a l l c e l l s become thicker-walled toward and within the l e a f base; a l a r c e l l s v a r i a b l e , but never sharply delimited, u n d i f f e r e n t i a t e d or recognizable as a small group of quadrate or short rectan-gular c e l l s grading imperceptable into other basal or lower median c e l l s . Plants pseudo-paroicous; perigonia and p e r i c h a e t i a clustered into aggreg-ations and subtended by common bracts; a single perigonium i s situated immed-i a t e l y beside a s i n g l e perichaetium or between 2 to 4 p e r i c h a e t i a , i n a l l cases the p e r i g o n i a l - p e r i c h a e t i a l complex i s enclosed within 2 to 3 small bracts; the e n t i r e complex i s borne i n the a x i l of a vegetative l e a f ; common bracts are broadly-ovate with a rounded or 1 to 3 lobed apex; p e r i g o n i a l leaves are ovate to ovate-lanceolate, the apex i s often abruptly acuminate l i k e the f o l i a g e leaves, ecostate, a r e o l a t i o n becoming rather incrassate and d i s t o r t e d , margins e n t i r e or very f i n e l y s e r r u l a t e , 0.4 to 0.6 mm long; outer and inner perichae-t i a l leaves d i f f e r i n g i n l i t t l e but s i z e , l i n e a r - l a n c e o l a t e , variously ecostate 213 or f a i n t l y single costae, deeply p l i c a t e - s u l c a t e , margins e n t i r e or very i r r e g u l a r l y toothed, leaves up to 2 mm long. Seta 9 - to 21 mm long, variously red to reddish-yellow, smooth, s t r a i g h t or s l i g h t l y i n c l i n e d when wet, twisting to the l e f t and becoming v a r i o u s l y contorted upon drying. Annulus deciduous, of 1 or 2 rows of c e l l s . Capsule as i n the genus. Peristome double; as per the genus; Endostome with 2 to 3 c i l i a , which are sometimes poorly developed. Spores smoky yellow, f i n e l y p a p i l l o s e , 12 to 23 um i n diameter. As noted by Limpricht (1882) the most unique feature exhibited by H. styriacum i s the pseudo-paroicous sexuality. In the absence of sexual r e -productive structures the species may be recognized by a combination of characters which include l e a f shape, the nature of the l e a f apex, the a l a r d i f f e r e n t i a t i o n and the structure of the costa. The leaves are b a s i c a l l y ovate, but the apex i s normally abruptly tapered to an acuminate point (Fig. 48 a - h). The alar c e l l s are u n d i f f e r e n t i a t e d or e x i s t as a few short rectangular c e l l s (Fig. 49 f.& g). The costa i s short and double or s i n g l e to s l i g h t l y beyond midleaf. In leaves of compar-able si z e the costa of H_, styriacum i s stouter than those of H_. luridum. Although Hygrohypnum styriacum (Limpr.) Broth, is- a d i s t i n c t i v e species, i t i s r e g u l a r l y confused with H. luridum and i n P a c i f i c Coastal North America i t often i s mistaken for H_. norvegicum. Grout (1931) remarked that "H_. styriacum (Limpr.) Broth, i s regarded by Limpricht himself as a subspecies of H . palustre and I have been unable to d i f f e r e n t i a t e American plants r e f e r r e d to i t from forms of palustre." I t i s obvious that Grout could not d i s t i n g u i s h the two taxa. However, I have seen ho l i t e r a t u r e corroborating the assertion ascribed to Limpricht. 214 When sex organs are av a i l a b l e for examination the unique p e r i g o n i a l -p e r i c h a e t i a l complex of Hygrohypnum styriacum i s c l e a r l y d i f f e r e n t from the autoicous condition present i n H. luridum. Further, c a r e f u l d i s s e c t i o n of operculate capsules of H_. styriacum w i l l r eveal an annulus at the base of the peristome. Hygrohypnum luridum does not possess an annulus. In the absence of sex organs and sporophytes Hygrohypnum styriacum and H. luridum may be distinguished through the contrasting gametophytic char-acters presented i n the following chart. Leaf Shape Alar C e l l s Median Leaf C e l l s Costa H_. styriacum Ovate with an abruptly tapered acumen. L i t t l e d i f f e r e n t from other basal c e l l s or a few quadrate or short rectangular c e l l s . Usually 28 - 40 um Stout H_. luridum Usually lanceolate or oblong lanceolate with a s l i g h t apiculus. Well defined group of quadrate to short rectangular c e l l s . Usually 30 - 55 um. Slender The abruptly narrowed acumen i n H_. styriacum varies i n a number of ways. In some cases i t ' i s squarrose (Fig. 48 j ) , i n others i t may.be s t r a i g h t (Fig. 48 i) , or i t maybe decidedly tur.ned to one side imparting a s l i g h t l y f a l c a t e appearance to the leaves (Fig. 48 j & k ) . In some cases'the apex i s more gradually tapered and such leaves are usually decidedly f a l c a t e . In general, however, the leaves are usually s t r a i g h t . Upon drying, the apex tends to r o l l up and twist, thus acquiring a f i l i f o r m appearance (Fig. 48 i) . Specimens of Hygrohypnum styriacum e x h i b i t i n g s l i g h t l y or decidedly f a l -cate leaves may be confused with the f a l c a t e forms of H. luridum. In f a l c a t e forms of H. luridum the a l a r c e l l s are frequently excavated, a condition never observed i n H. styriacum. 215 Hygrohypnum norvegicum i s best distinguished from H. styriacum on the basis of i t s ovate leaves, which have acute a p i c i e s . The a t t i t u d e of the leaves upon the stem and the length of the i n t e r -nodes may vary. In general, moist leaves are more or less s t r a i g h t and loosely imbricate (Fig. 48 i) . In the imbricated condition the leaves are close together. Often the internodes are long i n specimens'with spreading leaves. Those specimens with f a l c a t e leaves are also generally imbricate (Fig. 48 j & k ) . A number of e a r l i e r authors reported observations on c e r t a i n features of Hygrohypnum styriacum for which t h i s study has revealed greater v a r i a b i l -i t y than previously known or that or are d i f f e r e n t from present observations. Limpricht (1904) noted that the common bracts subtending the p e r i g o n i a l - p e r i -c h a e t i a l complex were 2 to 3 lobed. I have found them to vary from e n t i r e to 3 lobed. Limpricht (1904) also noted that the inner p e r i c h a e t i a l leaves were broadly costate. Roth (1905), on the other hand, said they were ecostate. Nyholm (1965) showed i n an i l l u s t r a t i o n ( f i g . 302) that they were strongly and broadly costate. This study has revealed that p e r i g o n i a l leaves and outer p e r i c h a e t i a l leaves are ecostate, whereas middle and inner p e r i c h a e t i a l leaves may be ecostate or weakly to strongly single costate. Limpricht (1904) described the stems of H. styriacum as f i l i f o r m . I have found the species to be no more slender than other Hygrohypna. Limpricht (1904) and Roth (1905) described the inner peristome teeth as not being cracked along the midline. I have found them to be i r r e g u l a r l y cracked. Monkemeyer' (1927) described the spores as smooth walled, when, i n f a c t , they are very densely p a p i l l o s e . In the o r i g i n a l d e s c r i p t i o n Limpricht (1882) c i t e d four specimens c o l l e c t e d by B r e i d l e r as the basis for the species. However, he d i d not designate a holo-type'from among these specimens. I have seen a l l of the c i t e d specimens and a number of t h e i r d u plicates. Of these specimens I have selected the following 216 specimen from the Limpricht herbarium at BP as being most representative of the species and designate i t as the lectotypeJLeg. J . B r e i d l e r 1 Sept 1880, Abhang am Schiedek die Patzenalm b e i Schladming ca 2800 m. There i s a s l i g h t discrepancy between the c i t a t i o n of t h i s specimen i n the o r i g i n a l d e s c r i p t i o n and the data borne on the l a b e l . The c i t a t i o n i n the d e s c r i p t i o n says "Nordabhand des.'......" and makes no mention of the proximity to Schladming. 217 Fig. 48 a - k. Variation i n leaf shape and shoot habit of Hygrohypnum  styriacum. a• r h. Variation i n leaf shape. i - k. Variation i n the habit of the shoot i n the moist condition. Scale: a T h; I 1mm | i - k; Each shoot i s approximately 1 cm long 218 219 c ' i F i g . 49 a - g. C e l l u l a r d e t a i l of the foliage leaves of Hygrohypnum  styriacum. a. Leaf apex. b and d. Median leaf c e l l s , c and e. Marginal leaf c e l l s , f and g. Alar c e l l s . Scale: a, f and g; | 100um I 220 2 2 1 222 E x s i c c a t i Examined Bauer, Musci europ. et amer. e x s i c c a t i # 1790. (BRNM, S-PA) Lisowski, Bryotheca Polonica Fasc. XXIV, # 636. (BP, CANM, S-PA, LE, NIGH) Fasc. XXV, # 666. (BP, CANM, S-PA, LE) Fasc. XXXI, # 823. (BP, CANM, S-PA, LE, NI<C-H) Selected Specimens Examined Canada B r i t i s h Columbia Ga r i b a l d i P r o v i n c i a l Park, Sentinal G l a c i e r at the E. end of G a r i b a l d i L; W. B. Sch o f i e l d 32918. as Hygrohypnum. luridum. (UBC) Gar i b a l d i P r o v i n c i a l Park, Whistler Mtn. Ski Area; D. W. Jamieson # 5472. (UBC) Vancouver Is., Strathcona P r o v i n c i a l Park, Golden Hinde; Boas 297 as Hygrohypnum luridum. (UBC) Sel k i r k Mtns., Zincton, Rambler Mine; F. A. MacFadden 3880 as Hygrohypnum palustre (UBC) Kitchener Krag; Boas 1960 as Hygrohypnum palustre. (UBC) Zincton, Lucky Jim Mine; F. A. MacFadden 3864 as Hygrohypnum pal u s t r e . (UBC) Wilmer, near Windemere, Paradise Mine; F. A. MacFadden 3878 as Hygrohypnum pa l u s t r e . (UBC) Sandon D i s t r i c t , Rambler Mine; F. A MacFadden 11 Sept... 1927 as Hygrohypnum pa l u s t r e . (MO, TENN) Eastern P a c i f i c Coast D i s t r i c t , Skagway (Alaska Quadrangle) Along the Haines Hwy, 83 miles NNW of Haines; F. J . Hermann 21843 As H_. norvegicum. (USA) Paradise Mine; F. A MacFadden 1 Aug. 1928 as Hygrohypnum palustre (MO, UC) Alberta Jasper National Park, Tonquin Valley; F. A. MacFadden 3875 as Hygrohypnum palustre (UBC) Bow River Watershed, S. t r i b u t a r y of Three I s l e Creek. W. of Upper Kamanaskis L.; B i r d & Glenn 13826 as Hygrohypnum luridum. (UAC & UBC) Jasper National Park, Wilcox F a l l s ; E. Whitehouse 25745 as Hygrohypnum pa l u s t r e . (USA) Jasper National Park, N. of Sunwapta Pass Campsite; O. D. Bird 5232. as Hygrohypnum luridum (UAC) United States C a l i f o r n i a ?; Ke l l o g . (USA) Water courses near Summit; H. Bolanderi 1864 - 1880. as Hypnum  styriacum (NY) T r i n i t y Co., Bullard's Basin; D. H. Norris 9287. as Hygrohypnum  luridum (HSC) Idaho Custer Co., Adair Creek; F. A. MacFadden 7 Aug. 1941. as Hypnum palustre (CANM, MICH, NY, TENN, TRTC) Lemhi Co., 8 miles N. of ghost town of Gibbonsville; T. C. Frye 1 Sept. 1929 as Hygrohypnum ochraceum (WTU) 223 Montana Gl a c i e r National Park, Hidden L. overlook-Logan Pass; F. J . Hermann 18094 as Hygrohypnum luridum (TENN) G l a c i e r National Park, Hanging Valley-Logan Pass; F. J . Hermann 18088 as Hygrohypnum luridum (NY) Between forks of Cut Bank Creek; R. S. Williams 26 July 1897 as Hypnum styriacum (C, MO, NY) Utah On stream above S a l t Lake; P. A. Evans 15 Aug. 1924 as Hygrohypnum palustre (NY) Wyoming Battle Lake Mth.; A. Nelson 4202. (NY) Norway Sorfolden; M. K o t i l a i n e n 25 July 1922 as Hygrohypnum styriacum (C, S-PA) Sweden Lule Lappmark, Roveguaare, Kvikkjokk; Hulphers 12 July 1937 as Hygrohypnum viridulum (S-PA) A u s t r i a T i r o l , Zunig b e i Windisch-Matrei oberhalb ?; J . Baumgartner 16 Sept 1905 as Musci europ. etamer. e x s i c c a t i # 1790. (BRNM, S-PA) Steiermark, Abhang am Schiedek d i ^ Patzenalm b e i Schladming, ca. 2000 m; J . B r e i d l e r 1 Sept 1880. LECTOTYPE. (BP) Poland Montes T a t r i A l t i , v a l l i s Dolina; Lisowski 27 Aug. 1956 as Bryotheca Polonica Fasc' XXIV, # 636. (BP, CANM, S-PA) 224 Hygrohypnum luridum (Hedw.) Jenn., Man. Moss. West. Pennsyl. 287. 1913. Neotype: "In Suecia ad trabes molendinica"; Swartz (G, sheet 3079/156) Hypnum luridum Hedw., Spec. Muse. 291. 1801. (Lectotype at G, sheet 3079/156) Hypnum palustre Huds. ex B r i d . , Musci Rec. 2(2):117. 1801. Hypnum molendinarium Lam et Cand., F l . Franc. Ed 2, 2:358. 1805.(Lectotype at G) Hypnum luridum var. ferrugineum B r i d . , Muse, Rec. Supp. 2:231. 1812. Hypnum neglectum B r i d . , Muse. Rec. Supp. 2:120. 1812. Hypnum subsphaericarpon Schleich. ex Br i d . , Muse. Rec. Supp. 2: 232. 1812. Hypnum aquatile Mart., F l . Crypt. E r l . , 19. I f . 2 A - K. 1817. Hypnum sphaericarpon Spreng., Syst. Veg. 4(1):201. 1827. Hypnum palustre var. a q u a t i l i s (Mart.) B r i d . , B r y o l . Univ. 2: 640. 1827. Hypnum palustre var. ferrugineus (Brid.) B r i d . , Bryol. Univ. ••• 2:641. 1827. Hypnum palustre var. luridum (Hedw.) Hamp., F l o r a (Jena) 20:274. 1837, Hypnum palustre var. subsphaericarpon Schwaegr. i n Hamp., Fl o r a (Jena) 20:274. 1837. Limnobium palustre. Schimp., Bryol. Eur. 6:66. 574. 1853. Amblystegium subenerve Schimp., Bryol. Eur. 6:52. 563. 1853. (Type at S-PA) Limnobium palustre var. subsphaericarpon (Brid.) Schimp. Bryol. Eur. 6:67. 575§- 1853. 225 Limnobium palustre var. hamulosum Schimp., Bryol. Eur. 6:67. 575/3 1853. Limnobium palustre var. julaceum Schimp., Bryol. Eur. 6:67. 5756 1853. Limnobium palustre var. laxum Schimp., B r y o l i Eur. 6:67. 575Y 1853. Hypnum roesei Schimp., C o r o l l . 131. 1856. Hypnum palustre var. tenellum Schimp., Syn. 634. 1860. Hypnum subeverve (Schimp.) Schimp., Syn. 634. 1860. Hypnum palustre var. hamulosum (Schimp.) Schimp., Syn. 634. 1860. Hypnum palustre var. julaceum (Schimp.) Schimp., Syn. 635. 1860. Hypnum palustre var. laxum (Schimp.) Schimp., Syn. 634. 1860. Hypnum palustre ssp. subsphaericarpon (Schleich. ex-Brid.) Lindb., Medd. Soc. F. FI. Fenn. 3:192. 1878. Amblystegium palustre (Brid.) Lindb., Musci Scand. 33. 1879. Hypnum k r a u s e i i C. Mull., F l o r a (Jena) 70:219. 1887. (Holotype at S-PA) Hypnum columbico-palustre C. Muell. et Kindb. i n Macoun, Cat. Canad. PI. 6:241. 1892. Scleropodium krausei (C. Muell.) Macoun et Kindb. i n Macoun, Cat. Canad. PI. 6:203. 1892. Hypnum pseudo-montanum Kindb. i n Macoun, Cat'. Canad. PI. 6:243. 1892. Limnobium pseudomontanum (Kindb.) Kindb., Canad. Rec. S c i . 6(1): 74. 1894. Ca l l i e r g o n palustre (Brid.) Kindb., Bot. Not. 1896:132. 1896. 226 Brachythecium krausei (C. Muell.) Par., Ind. Bryol. 136. 1894. Limnobium pachycarpulum. C. Muell., Nuov. Giorn. Bot. I t a l . n. ser. 3:116. 1896. Ca l l i e r g o n pseudomontanum (Kindb.) Kindb., Eur. N. Am. Bryin. 1:86. 1897. Amblystegium palustre var. hamulosum(B.S.G.) Braithw., B r i t . Moss. 3:60. 1898. Hypnum palustre var. roesei (Schimp.) Roth, Hedwigia 38:265. 1899. Hypnum pachycarpulum (C. Muell.) Par., Ind. Bryol. Supp. 206. 1900. Hypnum subeugyrium var. occidentale Card, et Ther. Proc., Wash. Ac. Sc. 4:342. 1902. Hygrohypnum palustre (Hedw.) Loesk., Mossfl. Harz. 319. 1903. Hygrohypnum palustre var. subsphaericarpon (Schleich. ex Brid.) Loesk., Moosfl. Harz. 320. 1903. Hygrohypnum palustre var. julaceum (B.S.G.) Loesk., Moosfl. Harz. 320. 1903. Hygrohypnum palustre var. laxum (B.S.G.) Loesk., Moosfl. Harz. 320. 1903. Limnobium sphaericarpon De Not. ex Par., Ind. Bryol. ed. 2, 3:194. 1905. Nom. i n v a l . i n synon. e r r , pre. L. subsphaericarpon (Brid.) De Not. Limnobium palustre var. tenellum (Schimp.) Roth, Eur. Laubm. 2:637. 1905. ' Hygrohypnum subsphaericarpon (Brid.) Loesk., Verh. Bot. Ver Brand-enburg. 49:198. 1905. Hygrohypnum subenerve (B.S.G.) Loesk., Verh. Bot. Ver. Brandenburg. 49:198. 1905. 227 Limnobium subenerve (B.S.G.) Roth, Eur. Lauta." 2:637. 56f4. 1905. Hygrohypnum palustre var. tenBllum (Schimp.) Warnst., Krypt. FI. Brandenburg 2:1060. 1906. Hygrohypnum palustre var. roesei (Schimp.) Roth ex Warnst., Krypt. FI. Brandenburg 2:1060. 1906. Nom. i n v a l . i n synon. e r r . pro. Hypnum palustre var. roesei (Schimp.) Roth. Hygrohypnum palustre var. tenuissimum Warnst., Krypt. F l . Branden-burg 2:1060. 1906. Hygrohypnum subsphaericarpon var. cataractum Loesk., A l l g . Bot. Zeit s c h r . 13:120. 1907.' Hygrohypnum krausei (C. Muell.) Par., C o l l . 16. 1909. Hygrohypnum subenerve var. hamulosum Glow., Carnolia n. ser. 4: 143. 1913. Hygrohypnum palustre fo. vu l g a r i s Moenk., Susswassfl. 151. f52a. 1914. Hygrohypnum palustre fo. hamulosa (B.S.G.)' Moenk., Susswassfl. 151. f52f. 1914. Hygrohypnum palustre var. subsphaericarpa (Schleich.) B.S.G. i n Moenk., Susswassfl. 151. f52c. 1914. Hygrohypnum palustre var. subsphaericarpa fo. julacea (B.S.G.) Moenk., Susswassfl. 151. f52d. 1914. Hygrohypnum palustre var, tsnella. (B.S.G.) Mosnk., Susswassfl. 151. 1914. Hygrohypnum palustre var. t e n e l l a fo. subenervis (Schimp.) Moenk., Susswassfl. 151. f52e. only. 1914. Hygrohypnum palustre var. subenervis (Schimp.) Moenk., Susswassfl. 151. 1914. Limnobium pseudochraceum Amann ex Roth, Hedwigia 57:139. 4f. 6. 228 1915. Hygrohypnum'palustre var. neglectum (Brid.) R o e l l , Hedwigia 56:267. 1915. Hygrohypnum palustre ssp. subenerve (B.S.G.) Amann, F l . Mouss. Suisse 2:358. 1919. Hygrohypnum palustre var. alpinum Amann, F l . Mouss. Suisse 2: 358. 1919. Hygrohypnum palustre var. eu-palustre fo. hamulosa (B.S.G.) Moenk., Laubm. Eur. 736. 1927. Hygrohypnum palustre var. eu-palustre f o . l l a x a (B.S.G.) Moenk., V -Laubm...Eur. 736. 1927. Hygrohypnum palustre var. tenellum fo. julacea (B.S.G.) Moenk., Laubm. Eur. 736. 1927. Hygrohypnum subenerve var. plumulosum Amann, Mem. Soc. Vaudoise H i s t . Nat. 3:63. 1928. Hygrohypnum pseudomontanum (Kindb.) Grout, Ch e c k l i s t Pleuroc. Moss. N. Am. 17. 1929. Hygrohypnum eugyrium var. occidentale (Card, et Ther.) Grout, Check-l i s t Pleuro. Moss. N. Am. 16. 1929. Hygrohypnum eugyrium ssp. subeugyrium var. occidentale (Card, et Ther.) Grout, Ch e c k l i s t Pleuroc Moss. N. Am. 16. 1929. Hygrohypnum palustre'ssp. pseudomontanum (Kindb.) Grout, Moss F l . N. Am. 3:89. 1931. Hygrohypnum luridum fo. hamulosum (B.S.G.) C. Jens., Skad. Bladmf1. 465. 1939. Hygrohypnum luridum fo. julaceum (B.S.G.) C. Jens., Skad. Bladmf1. 465. 1939. 229 Hygrohypnum luridum fo. laxum (B.S.G.) C. Jens., Skand. Bladmfl. 465. 1939. Hygrohypnum luridum fo. subenerve (Schimp.) C. Jens., Skand. Bladmfl. 465. 1939. Hygrohypnum luridum var. subsphaericarpon (Schleich.) C. Jens., Skand. Bladmfl. 465. 1939. Hygrohyphum palustre var. malacocaulon Herz., Hedwigia 82:87. 14. 1944. Hygrohypnum nervosissimum Parr., Rev. Bryol. Lichen. 21:17. 15f. 1 - 8 . 1952. Hygrohypnum luridum var. eu-luridum fo. vulgare (Moenk.) Podp. Consp. 571. 1954. Hygrohypnum luridum var. eu-luridum fo. hamulosum (B.S.G.) Podp., Consp. 571. 1954. Hygrohypnum luridum var. eu-luridum fo. laxum (B.S.G.) Podp., Consp. 571. 1954. Hygrohypnum luridum var. tenellum (Schimp.) Podp., Consp. 571. 1954. Hygrohypnum luridum var. tenellum fo. subenerve (Schimp.) Podp., Consp. 571. 1954. Hygrohypnum luridum var. tenellum f o . plumulosum (Amann) Podp., Consp. 571. 1954. Hygrohypnum luridum var. tenellum fo. hamulosum (Glow.) Podp., Consp. 571. 1954. Hygrohypnum luridum var. tenellum fo. tenuissimum (Warnst.) Podp Consp. 571. 1954. Hygrohypnum luridum var. malacocaulon (Herz.) Podp., Consp. 572. 2 30 Hygrohypnum luridum var. julaceum (B.S.G.) Podp., Consp. 572. 1954. Hygrohypnum luridum var. subsphaericarpon fo. cataractum (Loesk.) Podp., Gonsp. 572. 1954. Hygrohypnum luridum var. pseudochraceum (Amann) Podp., Consp. 572. 1954. Hygrohypnum luridum var. pseudochraceum fo. alpinum (Amann) Podp., Consp. 572. 1954. Nomina Nuda Hygrohypnum luridum var. eu-luridum fo. complanata (Roell) Podp., Consp. 571. 1954. Hygrohypnum luridum var. obtusatum (Loesk. et S t o l l e i n Roell) Podp., Consp. 572. 1954. Hygrohypnum palustre var. complanatum Ro e l l , Hedwigia 38:265. 1899. Hygrohypnum palustre var. obtusatum Loesk. e_t S t o l l e i n Ro e l l , Hedwigia 56:267. 1915. Hypnum palustre var. auronitens Progel i n Mol., Jahresber. Naturh. Ver. Passau 10:2'68. 1875. Hypnum palustre var. pachyneuron Glow., Verh. Zool. Bot. Ges. Wien 57:22. 1907. Hypnum -palustre var. orthocarpon Saut., M i t t h e i l . Ges. Salzb. Landesk. 10:69. 1871. Hypnum palustre var. p f e f f e r i Lor, i n Limpr.,. "Krypt. F l . Schles. 1:63. 1876. Hypnum palustre var. stabianum Bott., A t t i Soc. Toscana Sc. Nat. 92:190. 1913. 231 Nomena Nuda not seen Hypnum dolichoneuron Ingl. et Rhodes Ann. Rep. Moss Each. Club. 21:145 - 167. 1916. Hypnum palustre var. g r a c i l u s Ren. i n Holzinger, Bry o l o g i s t . 13:53. 1913. Names treated as synonyms elsewhere, but for. which the l i t e r a t u r e was unavailable f o r assessment during t h i s study. Hygrohypnum luridum fo. intextum C. Muell., Syn. 2:142. 1851. Hypnum intextum V o i t , i n Sturn. F l . Deutsch. 2:11 i c . 1811. Hypnum pseudo-plumosum var. subsphaericarpon (Brid.) Spruce, Ann, Mag. Nat. H i s t . ser. 2. 3:281. 1849, Limnobium ambiguum De Not., Cronac. B r i o l . I t a l . 2:27. 1867. Limnobium reptileforme De Not., Cronac. B r i o l . I t a l . 2:27. 1867. Limnobium subsphaericarpon (Brid.) Lindb., Medd. Soc. F. F l . Fenn. Names of c e r t a i n taxa and t h e i r alleged synonyms for which the l i t e r a t u r e was examined, but found inadequate f o r e f f e c t i v e assessment of the taxon i n the absence of the type specimens. Hypnum ruderale var. intricastum B r i d . , Bryol. Univ. 2:584. 1827. Hygrohypnum luridum fo. intricastum (Brid.) C. Jens. Skand. Bladmfl. 465. 1939. Hypnum palustre var. prolixum Mat., Hedwigia 44:44. 1905. Hygrohypnum palustre var. prolixum (Mat.) Warnst., Krypt. F l . Brandenburg 2:1060. 1906. Hygrohypnum luridum fo. prolixum Podp., Consp. 571. 1954. Names of taxa not present at the designated s i t e s i n the l i t e r a t u r e . Hygrohypnum luridum fo. ambiguum c f . Jens., Skand. Bladmfl. 465. 1939. f i d e Index Muscorum. 232 Hygrohypnum luridum fo. intricastum C. Jens., Skand. Bladmf1. 465. 1939. f i d e Index Muscorum. Hygrohypnum luridum fo. reptileforme (De Not.) c f . C. Jens., Skand. Bladmf1. 465. 1939. f i d e Index Muscorum. Hygrohypnum luridum+var. tenellum fo. subenerve C. Jens., Skand. Bladmf1. 465. 1939. fi d e Pddper'a inrConsp. 233 Plants slender to robust, forming loosely to t i g h t l y woven patches or t u f t s , often forming extensive mats; when loosely woven the patches or t u f t s e a s i l y fragment; plants frequently clogged with s i l t to varying degrees. Color v a r i a b l e , yellow-green to yellow-green with rusty mottling, le s s often yellow-brown, b r i g h t green, blackish-green or brownish-black, at times a l l color v a r i a t i o n s may grade from one to another within the same plant. Stems (1) 3 - 5 (6) cm long; mainly prostrate and creeping, but ascending at the apex; stems sometimes hooked at the apex; usually f o l i o s e throughout, i n some o l d specimens the leaves near the stem base may be badly abraded, but seldom are the stems c l e a r l y denuded. Branching i r r e g u l a r , branches 1 - 2 (3) cm long, generally ascending, sometimes erect, stem cross-sections revealing 3 to 4 rows of small, yellowish or brownish, thick-walled c o r t i c a l c e l l s ; medullary c e l l s thinner-walled, increasing i n s i z e toward the middle; c e n t r a l strand well developed, of numerous small c e l l s ; medullary c e l l s and the c e n t r a l strand generally becoming more darkly pigmented with age; r h i z o i d s of v a r i a b l e frequency, reddish-brown, a r i s i n g at the base of ventral stem leaves. Leaves v a r i a b l e , but changing l i t t l e from the wet to dry condition; (0.5) 1.0 - 1.5 (2.5) mm long X (0.25) 0.4 - 0.75 (1.1) mm wide; shape v a r i -able, lanceolate, oblong-lanceolate, ovate and o c c a s i o n a l l y broadly ovate; leaves s t r a i g h t for f a l c a t e , r a r e l y almost c i r c i n a t e ; apex i n lanceolate or severely f a l c a t e leaves usually tapering gradually to an acute point; i n oblong-lanceolate, ovate or l e s s severely f a l c a t e leaves the apex usually tapering i n t o a small abruptly d i f f e r e n t i a t e d apiculus; margins e n t i r e , i n r o l l i n g v a riously, frequently i n r o l l i n g on one side of the l e a f creating i n f o l d e d wings; i n oblong-lanceolate or ovate leaves margins frequently i n r o l l on both sides of the l e a f i n upper quarter accentuating the abruptly tapered apiculus. Leaves 234 va r i o u s l y d i s t a n t to crowded; a t t i t u d e upon stem v a r i a b l e , spreading, loosely to t i g h t l y imbricated, almost j.ulaceous or any v a r i a t i o n of f a l c a t e from s l i g h t l y curved to almost c i r c i n a t e ; two or more of these v a r i a t i o n s may occur as a.gradient along a given length of stem or branch, the most frequent v a r i a t i o n combination being imbricate-falcate or vice versa; frequently a degree of c o r r e l a t i o n e x i s t s between l e a f shape or degree of f a l c a t i o n and l e a f p o s i t i o n upon the stem—lanceolate leaves seem to e x h i b i t a greater frequency i n the spreading a t t i t u d e ; among f a l c a t e leaves there i s an occasional tendency for leaves positioned d o r s a l l y on prostrate 'stems to be strongly f a l c a t e with decidedly i n r o l l e d margins while leaves positioned on the flanks of such prostrate stems are often rather ovate, gently f a l c a t e with the d o r s a l l y proximal margin infolded as a wing, and the v e n t r a l l y placed leaves may e i t h e r be squarrose-caniculate or v a r i o u s l y f a l c a t e i n the upper h a l f . Leaves almost plane, shallowly con-cave or caniculate, e s p e c i a l l y when f a l c a t e . Costa varies continuously throughout the species and within i n d i v i d u a l leaves of the same plant; single and short to percurrent, short and double or absent. Areolation extremely v a r i a b l e ; median l e a f c e l l s variously short rhombic to long, l i n e a r flexuose, (28) 30 - 55 (95) um long X (4) 5 - 7 (12) um wide; the average dimensions of median l e a f c e l l s may vary from one l e a f to another on the same stem; a p i c a l l e a f c e l l s generally shortening gradually or changing l i t t l e from the median c e l l s ; basal l e a f c e l l s become shorter and wider than median l e a f c e l l s or only s l i g h t l y wider: i n e i t h e r case the basal c e l l s may be weakly to strongly p i t t e d i f at a l l ; a l a r c e l l s v a r i a b l e , present as a w e l l -defined group of quadrate, short rectangular or i r r e g u l a r l y shaped c e l l s ; varying from t h i n and hyaline to incrassate and discolored yellow-brown or reddish-brown; plane or excavated, excavated c e l l s sometimes be i n f l a t e d to 235 varying degrees. Plants autoicous; perigonia ovate; p e r i g o n i a l leaves ovate to ovate-lanceolate 0.3 - 0.7 mm long, deeply concave imbricate, e n t i r e , ecostate, enclosing several antheridia and numerous paraphyses'; Outer and middle p e r i -c h a e t i a l leaves ovate lanceolate or lanceolate, squarrose recurved i n the upper h a l f , costa single or absent; inner p e r i c h a e t i a l leaves long tapering lanceolate, to 3.5 mm long, erect, e n t i r e , costa strong and s i n g l e or long and double or almost absent, stout or slender. Seta 8 - 2 4 mm long, smooth walled, erect or arching when moist, var-iously twisting upon drying. Capsule 1 - 3 mm long; when wet usually i n c l i n e d arcuate, less often erect c y l i n d r i c a l ; upon drying the capsule may or may not c o n s t r i c t below the mouth, when cons t r i c t e d below the mouth the lower h a l f of the capsule i s rather bulbous. Capsule wall c e l l s incrassate, yellow or reddish-brown, oval, quadrate, rectangular or i r r e g u l a r . Capsules with tap-ering neck bearing 8 - 3 0 s u p e r f i c i a l stomata. Peristome t y p i c a l for the genus; annulus absent, endostome with 1 - 3 poorly to well defined c i l i a . Spores dusky yellow, p a p i l l o s e , 10 - 26 um i n diameter. Hygrohypnum luridum (Hedw.) Jenn. i s an extremely variable species. A measure of t h i s v a r i a b i l i t y i s seen i n the 115 names ascribed at the s p e c i f i c and subspecific l e v e l s . However, t h i s study shows that H. luridum must be viewed as a s i n g l e , exceedingly polymorphic species that cannot be e f f e c t i v e l y subdivided into morphologically consistent taxa. The species varies v i r t u a l l y continuously i n nine or ten features, which have been used singly or i n various combinations as c r i t e r i a for the recognition of numerous subspecific taxa. These are o v e r a l l plant s i z e , l e a f shape, attitu d e of the leaves on the stem, degree of f a l c a t i o n , degree of i n r o l l i n g of the l e a f margin, internode length, 236 c o s t a l structure, degree of l e a f concavity, a l a r d i f f e r e n t i a t i o n and the degree to which the alar c e l l s are excavated. The s i z e or o v e r a l l robustness of t h i s species varies widely. This v a r i a t i o n i s d i f f i c u l t to measure and i s dealt with i n q u a l i t a t i v e terms, which unfortunately are vague and imprecise. Hygrohypnum luridum can form small patches or t u f t s a few centimeters square a l l the way to extensive mats several decimeters across. These may beryeryoloosely woven and e a s i l y fragmented or t i g h t l y woven with l i t t l e fragmentation. These patches or mats may be t h i n due to the p r o s t r a t i o n of t h e i r component branches or they may be thick and almost t u r f l i k e as a consequence of the ascending branches and stem t i p s . Stems can be slender, that i s less than 1 mm i n diameter, or thicker,' ca. 2.5 mm. (Thickness i s the distance i n moist plants from l e a f t i p to l e a f t i p from one side of the stem to the other.) V a r i a t i o n i n stature i s a frequent environmental response among plants, thus i t seems reasonable to assume that v a r i a t i o n of t h i s sort i s such a response. The leaves are exceedingly v a r i a b l e . Certain features vary and these v a r i a t i o n s i n turn influence the v a r i a t i o n of other l e a f features. Conse-quently, the variable l e a f characters are d i f f i c u l t to t r e a t i n d i v i d u a l l y . Basic l e a f shape varies from narrowly lanceolate (Fig. 51 m) to ovate (Fig. 51 b). The most common shape i s ovate lanceolate or oblong-lanceolate (Fig. 51 f, g, i , o, p, q e t c ) . Leaves e x h i b i t i n g such shapes often occur on the same plants and i n rare instances they may occur immediately adjacent' one another with out leaves t r a n s i t i o n a l shapes between them. The l e a f apex may gradually taper to a sharp point (Fig. 51 j & m), but i n most instances appears to taper abruptly to an apiculate point (Fig. 51 f, p, e t c ) . This i s most evident i n oblong ovate or oblong lanceolate leaves. 237 In r e a l i t y the apices gradually taper to an acute point (Fig. 53 a & b) but appear apiculate r e s u l t i n g from the i n r o l l i n g of the l e a f margin just below the apex. This accentuates the taper and a r t i f i c i a l l y d i f f e r e n t i a t e s the apiculus. As continuous as the v a r i a b i l i t y of le a f shape i s with i t s attendent modifying features, c e r t a i n features show a c o r r e l a t i o n with l e a f shapes. Narrowly lanceolate to ovate lanceolate leaves are frequently variously f a l c a t e . Such leaves vary from s l i g h t l y f a l c a t e (Fig. 51 n) to almost c i r c i n a t e (Fig. 52 v ) A n ent i r e l e a f may be f a l c a t e (Fig. 52 u) or only the upper h a l f (Fig. 52 p). The asymmetry of a l e a f as a consequence of the f a l c a t i o n may also be more evident on one side of the l e a f (Fig. 51 e). Very commonly the degree of f a l c a t i o n may depend on the dorsal, l a t e r a l or v entral i n s e r t i o n of the leaves upon the prostrate stem. Dorsally placed leaves may be severely f a l c a t e to almost c i r c i n a t e and deeply tubulose. Such leaves arch high above t h e i r point of i n s e r t i o n , curving abruptly toward the substrate and occasionally the t i p s curve completely beneath the stem (Fig. 50 d). In other instances the dorsal leaves simply curve gradually toward the substrate. Sometimes i n the more ovate lanceolate leaves the expression of f a l c a t i o n i s confined to the upper h a l f of the l e a f , or i s at l e a s t more con-spicuous there. In these the f a l c a t e upper h a l f i s severely curved and deeply tubulose (Fig. 51 1). Leaves inserted l a t e r a l l y on the prostrate stem may ei t h e r be severely f a l c a t e as those d o r s a l l y inserted or may be fa l c a t e by means of an i n r o l l e d l e a f margin. In th i s l a t t e r s i t u a t i o n the l e a f nearer the dorsal side of the stem i s i n r o l l e d toward the l e a f midline. Such a l e a f may be gradually or•abruptly f a l c a t e . The more ovate lanceolate leaves in s e r t e d l a t e r a l l y generally are more gradually f a l c a t e than narrower leaves. Less f a l c a t e ovate lanceolate leaves are placed adaxial side down on a micro-2 3 8 scope s l i d e and covered with a cover s l i p , they are seen to lose t h e i r f a l c a t e appearance. Thus the i n r o l l e d wing opens when the le a f i s placed adaxial side down. The pressure of the cover s l i p f l a t t e n s the l e a f , making i t appear more t r u l y ovate lanceolate. This, however, i s a variable phenomenon. Leaves situated v e n t r a l l y on a prostrate stem are also v a r i a b l y f a l c a t e . Sometimes•these are not so much f a l c a t e as they are squarrose tub-ulose i n the upper h a l f (Fig. 51 c) and occasionally, the squarrose tubulose upper h a l f i s deflected to one side by the substrate. On-some plants with p r i m a r i l y f a l c a t e the ve n t r a l leaves are p e r f e c t l y ovate lanceolate with no hi n t of f a l c a t i o n . In these, the ve n t r a l leaves are imbricated among them-selves . Narrowly lanceolate or ovate leaves may vary s t i l l f urther. Generally the leaves are quite crowded along the stem or they may be quite d i s t a n t . There di s t a n t leaves may.occur i n two regions; on slender branches, or i n post e r i o r portions of older stems. I f often appears that concavity varies d i r e c t l y with f a l c a t i o n . The more pronounced the f a l c a t i o n , the more pro-nounced the l e a f concavity or ca n i c u l a t i o n . Frequently, the narrowly lanceolate or ovate lanceolate leaves are s t r a i g h t , e x h i b i t i n g no f a l c a t i o n . In these instances, there i s v a r i a t i o n i n the attitude of the leaves upon the stem, spacing of the leaves along the stem, the l e a f concavity and the i n r o l l i n g of the margin. These leaves vary from t i g h t l y imbricated to very widely spreading.and they vary from crowded to di s t a n t . In some cases, those leaves that are widely spreading and d i s t a n t are also crisped when dry and ex h i b i t considerable l a t e r a l shrinkage coupled with some twisting. Not infrequently, those axes bearing crisped, widely spaced, spreading leaves are rather spindly secondary branches. In s t r a i g h t , narrowly lanceolate to ovate lanceolate leaves concavity when present i s more 2 3 9 evident than i n f a l c a t e leaves which often p a r t i c u l a r l y evident when the leaves are imbricated. Sometimes i n very long, old stems the narrowly lanceo-l a t e to ovate leaves are widely spaced and grade from very small si z e to normal from the stem base to the apex. This phenomenon appears to be the r e s u l t of maturation from juvenile to adult leaves. In a s i g n i f i c a n t l y large number of specimens leaves occur i n such shapes as; ovate, but narrowing to an acuminate t i p ; oblong to oblong ovate with acute t i p ; and broadly ovate or broadly lanceolate. These basic shapes grade imperceptibly from one to another, v a r y i n g 5 i n a number of minor feat-ures. Most importantly, leaves of•, these shapes are most t y p i c a l l y s t r a i g h t . Beyond t h i s , these leaves may vary i n t h e i r attitude upon the stems, t h e i r spacing along the stem, t h e i r concavity and the degree of i n r o l l i n g of the l e a f margins. A frequent modification among these leaves has to do with the i n r o l l i n g of the l e a f margin and the d e l i m i t a t i o n of a small apiculus. In a l l of these l e a f shapes i t i s common for the margin to i n r o l l s l i g h t l y from near midleaf to shortly below the apex. As a r e s u l t of the i n r o l l i n g , the taper of the l e a f near the apex i s abruptly changed such that an a p i c a l apiculus i s evident. ~The spacing of these variously shaped leaves on the stem varies from very widely spaced to very crowded. They may further vary from spreading to imbri-cated. Sometimes they are concave or weakly tumid. At other times they are v i r t u a l l y plane.- Frequently, much of t h i s v a r i a t i o n may be evident along a gradient from p o s t e r i o r of the stem to the stem apex. In such cases the leaves at the p o s t e r i o r stem extremities are widely spaced and spreading to almost erect spreading. Toward the stem apex the leaves become gradually more crowded and conspicuously imbricated. The concavity of these leaves varies qiite widely and i n isome cases the leaves are almost cuculate, whereas, i n others, the concavity i s very shallow. A consequence of the pronounced concavity i n 240 some leaves the stems are julaceous. T y p i c a l l y Hygrohypnum luridum has a well defined group of quadrate to short rectangular or occasionally i r r e g u l a r l y shaped a l a r c e l l s (Fig. 54 a & b). T y p i c a l l y the c e l l s are incrassate, but they may be somewhat th i n walled. They may be hyaline or strongly discolored yellow to red-brown and may vary from plane to decidedly excavated (Fig. 54 d - f ) . Each of these variables may occur on the same plant and i n the same l e a f . There does seem to be a greater frequency for excavated a l a r c e l l s i n f a l c a t e leaves than i n s t r a i g h t ' l e a v e s . Alar c e l l s of Hygrohypnum luridum have never been described as i n f l a t e d . However, a few a l a r c e l l s i n f a l c a t e leaves with excavated.'alar zones may be quite i n f l a t e d (Fig. 54 f ) . Among st r a i g h t , almost broadly ovate leaves there i s also a greater frequency of thin-walled, hyaline or only s l i g h t l y d iscolored a l a r c e l l s . The costa of Hygrohypnum luridum i s exceedingly v a r i a b l e and i s so independent of any other l e a f character. The costa varies from strong, si n g l e and percurrent to short and double to v i r t u a l l y absent. Among the very smallest'leaves the costa i s more frequently absent, but t h i s does not mean that larger leaves have more well developed costae. In f a c t , they too may completely lack a costa. As with other l e a f features i t i s not un-common for the e n t i r e range of v a r i a t i o n to occur within one plant. In the o r i g i n a l d e s c r i p t i o n of Hypnum luridum Hedwig (1801) did not designate a type specimen. Hedwig did give habitat and geographical date i n d i c a t i n g that the plant was c o l l e c t e d from decaying matter i n Sweden and Germany. Thorough study of the species has revealed that only two specimens that are a t t r i b u t a b l e to Hedwig and/or his herbarium are i n existance. Both specimens are at G. One specimen bearing no c o l l e c t i n g date i s named Hypnum  subsphaericarpon. I t bears the G accession number 3079/184. The second 241 specimen i s e n t i r e l y representative of the f a l c a t e forms of the species, i t comes from an acceptable geographical area and at l e a s t o f f e r s the p o s s i b i l i t y of having been seen by Hedwig. Therefore, I designate G sheet number 3079/156 as the neotype- for Hygrohypnum luridum (Hedw.) Jenn. From out of the mass of character v a r i a t i o n that i s Hygrohypnum luridum numerous past workers have perceived and described as assortment of sub-s p e c i f i c taxa. The non-existence of the type specimens for many of these taxa or at l e a s t t h e i r u n a v a i l a b i l i t y for the purposes of t h i s study and the ambiguity of many of t h e i r type descriptions has made d i f f i c u l t an assessment of t h e i r r e a l i t y . Careful study of the a v a i l a b l e type descriptions, other c r i t i c a l l i t e r a t u r e and a d e t a i l e d analysis of over 500 specimens of the species from throughout i t s range has permitted an assessment of the species and i t : alleged s u b s p e c i f i c taxa as recognized by Index Muscorum (1959 - 1969). I t i s the author's opinion that there are no morphologically consistent en-t i t i e s within the species. A l l <nf the subspecific taxa have been based on var-i a b l e features or have been erroneously placed within the species.' Hygrohypnum luridum var. subsphaericarpon (Brid.) C. Jens., Hygrohypnum  luridum fo. alpinum (Amann) Podp. and Hygrohypnum luridum fo. nervosissimum (Parr.) Podp. have been based p r i m a r i l y on the strength of t h e i r costae. Of Hypnum subsphaericarpon, B r i d e l (1812) noted "nervo fubexcurrente" and went on to say "supreme tantum falcato-fecundo nervo c r a f f o ferrugineo-fusco ad apicem producto f p e c i f i c diftinctum." Amann (1912) characterized the leaves of H. luridum var. alpinum as having conspicuously i n r o l l e d margins near the apex and a strong costa prolonged to j u s t beneath the apex. P a r r i a t (1952) noted that Hygrohypnum nervosissimum had apiculate leaves with the margin i n r o l l e d and a si n g l e costa disappearing just below the apex, sometimes with a c o s t a l 242 branch reaching midleaf. That these plants are c l e a r l y recognizable i s indisputable. However, as discussed e a r l i e r the costa varies continuously throughout the species. I t i s easy to f i n d plants resembling each of these taxa i n a l l respects, but possessing a short double costa or a v a r i a b l e mix-ture of strong single and short and double costae. Each of these taxa simply represent that end of the spectrum of c o s t a l v a r i a t i o n i n which the costae are a l l , or almost a l l , strong and s i n g l e . Consequently, these taxa do not warrant taxonomic recognition. Hygrohypnum luridum fo. laxum (B.S.G.) Podp., Hygrohypnum luridum fo. tenuissimum (Warnst.) Podp.,.Hygrohypnum luridum var. tenellum (Schimp.) Podp. and Hygrohypnum luridum fo. subenerve (Schimp.) C. Jens, are a l l based on s i m i l a r features. In general they are characterized as slender or small plants. Schimper (1853) described var. laxum as " g r a c i l o r e s , partim denud-atue. F o l i a remotiuscula, undique patentia, ovato-lanceolata." Schimper (1876) further characterized Limnobium palustre var. tenellum as "minus, formis majoribus H_. i n c u r v a t i s i m i l i , f o l i s i l l i s var. (Laxum) sat s i m i l i b u s , subito acuminatis." Schimper (1853) described Amblystegium subenerve as "laxue cae-spitosum, rigidulum; caule d i v i s i o partim denudato vage pinnatim ramuloso; f o l i s acuminate-ovatis, valde concavis, semi-costatis, costa lutescente s i m p l i c i v e l b i f u r c a , i n t e r r i m i s " F i n a l l y , Warnstorf (1906) described H. palustre var. tenuissimum as stems very short, asending, , leaves moderately loosely spaced, mostly c l e a r l y secund, small lanceolate, 0.5 to 0.8 mm X 0.2 to 0.3 mm, ecostate or with a very short, very t h i n simple costa. Only the type of Ambly-*. stegium subenerve Schimp. (at S-PA) was available for study. However numerous specimens variously determined as one or the other of these taxa have been examined. In most cases, such plants are i n v a r i a b l y very poor and fragmented specimens, often consisting of only a few stems. These plants appear to have grown under less than optimal environmental conditions. I t i s l i k e l y , there-243 fore, that each of these alleged taxa are morphological abberations and not worthy of taxonomic recognition. O v e r a l l s i z e , l e a f f a l c a t i o n , and costalJmorphology, a l l v a r i a b l e characters, have been used to characterize Hygrohypnum luridum var. sub- sphaericarpon (Brid.) O. Jens., H_. luridum fo. hamulosum (B.S.G.) C. Jens., H. luridum ssp. pseudomontanum (Kindb.) Wijk et Marg., H_. luridum var. mal- ococaulon (Herz) Podp. and H_. luridum fo. tenuissimum (Warnst.) Podp. Various workers (B r i d e l , 1812; Schimper, 1853, 1876; Limpricht, 1904; Moehkemeyer, 1927; Nyholm, 1965; Grout, 1931; Lawton, 1971; Dixon, 1924; Braithwaite, 1898; Husnot, 1894; Roth, 1905; Jensen 1939; Milde, 1869; Sprengel, 1827) have a l l variously described H. luridum var. subsphaericarpon as a very robust plant with large, very f a l c a t e secund, concave leaves with a strong, slender costa reaching 3/4 of the l e a f length. S i m i l a r l y , many of these same authors (Schimper, 1853, 1876; Limpricht, 1904; Husnot, 1894; Braithwaite, 1898; Dixon, 1924; Nyholm, 1965; and Moenkemeyer, 1927) v a r i o u s l y described fo. hamu- losum as a small, slender p l a n t with falcatefeseeund leaves. However, only Schimper, Dixon, Braithwaite and Husnot remarked on the short and double nature of the costa. Kindberg (1897) observed the s i m i l a r i t y of ssp. pseudo-montanum with Hygrohypnum montanum on the basis of the variously incurved or recurved f a l c a t e leaves. He distinguished the subspecies on the basis of i t s longer more robust stems, the larger, thinner more loosely disposed, longer decurrent, less d i s t i n c t l y s e r rulate leaves, whose alar c e l l s were larger and whose costa was simple and prolonged to above the middle. Warnstorf (1906) characterized var. tenuissimum as having very short (1 cm), ascending stems, bearing rhizoids only near the base and whose leaves were rather loosely spaced, c l e a r l y secund, narrowly lanceolate, usually 0.5 to 0.6 mm long X 0.2 mm wide, ecostate to short costate and bearing a few quadrate to short rectangular alar* c e l l s . 2 4 4 Study of var. subsphaericarpon, fo. hamulosum and fo. tenuissimum have shown them to based on continuously v a r i a b l e o v e r a l l p l a n t s i z e , l e a f f a l c a t i o n and c o s t a l morphology. Very large, robust f a l c a t e leaved plants may have short and double or si n g l e costae or they may be ecostate. Sim-i l a r l y , small, slender f a l c a t e leaved plants may have strong single or short double costae. The ambiguous concepts of robust and small and slender have caused previous workers to c a l l plants of e s s e n t i a l l y the same s i z e both var. subsphaericarpon and fo. hamulosum regardless of the plant's r e a l l i n e a r dimensions. A more fundamental problem among these taxa i s the very frequent occurrence of s t r a i g h t leaves on stems bearing a majority of f a l c a t e leaves. I t i s not unusual to come upon stems that have segments of f a l c a t e leaves a l t e r n a t i n g at i r r e g u l a r i n t e r v a l s - w i t h segments bearing s t r a i g h t leaves. As a consequence, none of the characters serving as the basis f o r these taxa are s u f f i c i e n t l y consistent to serve as a sound taxonomic base. Therefore, I do not recognize these taxa. The p o s i t i o n of Hygrohypnum luridum ssp. pseudomontanum i n t h i s group i s somewhat ambiguous. As noted e a r l i e r , Kindberg (1931) treated the supposed subspecies as a species a l l i e d with Hygrohypnum montanum. The fa c t s are that the supposed subspecies i s not even remotely r e l a t e d to H_. montanum, but i s a vari a n t of H, luridum. Kindberg accurately noted the frequent s i m i l a r i t y of the v a r i a b l e incurvature and recurvature of the l e a f margins. He mistakenly noted the le s s d i s t i n c t l y s e r rulate l e a f margins. The alleged subspecies i s i n f a c t c l e a r l y e n t i r e . Kindberg c o r r e c t l y observed that the leaves of the so c a l l e d subspecies were larger than those of H.^montanum. However, the l e a f s i z e of ssp. pseudomontanum should be compared with the slender, f a l c a t e leaved forms of H. luridum that have been a t t r i b u t e d to fo. hamulosum. The subspecies was o r i g i n a l l y described from Owen Sound, Ontario. Plants from t h i s area and the adjacent Great Lakes area are often s l i g h t l y l a r g e r than the 245 traditional fo. hamulosum. Grout (1931) accurately noted the slightly blunter leaf apices which often occur in ssp. pseudomontanum. However, the character merges imperceptibly with other small falcate leaved var-iants of H. luridum in the Great Lakes area. Grout (1931) accurately noted the simultaneous occurrence of straight and falcate leaves in ssp. pseudomontanum, but did not attach any significance to the fact. Hygro- hypnum luridum ssp. pseudomontanum is not worthy of formal recognition. Plants bearing straight, julaceous or loosely imbricated, oblong ovate to broadly lanceolate leaves with more or less abruptly acuminate apicies and having strong single costae have long been treated as the variety or form julaceum of Hygrohypnum luridum. These plants have been so treated by Schimper (1853, 1876), Limpricht (1904), Grout (1931), Dixon (1924), Husnot (1894) and Roth (1905) . As noted previously the costa varies more or less continuously throughout the species. Much weight has been placed on straight and falcate leaves in the recognition of subspecific taxa in Hygrohypnum luridum. Leaves of both shapes are frequently observed on the same stems in the species and thus invalidate the characters as use-ful in this species. Muller (1887) described Hypnum krausei from Takhim Valley, Alaska. Grout (1931) treated the plant as synonymous with Hygrohypnum alpestre. Examination of a duplicate of the type at N Y reveals that the plant is the common western North American form ;of Hygrohypnum luridum. Hygrohypnum luridum var. crassinervium (Baur.) Podp. is a depauperate form of Hygrohypnum smithii (Sw. in L i l j . ) Broth. Hygrohypnum luridum var. ehlei (Arn.) Wijk et Marg. is a falcate leaved form of U. polare (Lindb.) Loesk. For a complete discussion of the Arnell plant see the treatment of H. polare. 246 Roell (1899) used the epithet complanatum for what he viewed as new var i e t y of H_. luridum. The name was used i n the absence of a formal L a t i n d e s c r i p t i o n nor was a specimen c i t e d . The name i s a nomen nudum. Later Roell (1915) published the name Hygrohypnum palustre var. ob-tusatum which he credited to Loeske. The name was accompanied neither by a L a t i n d e s c r i p t i o n nor a c i t e d specimen and i s therefore a nomen nudum. Wijk et a l . (1964) c r e d i t De Notaris f o r authoring the names Limnobium  r e p t i l i f o r m e and L_. ambiguum. Neither descriptions nor specimens of such plants have been a v a i l a b l e for study. Further, Wijk et a l , (1962) noted that Jensen (1939) reduced the two De Notaris taxa to forms of Hygrohypnum luridum. The Wijk reference to Jensen's work i s mistaken for Jensen c l e a r l y makes no mention of the De Notaris taxa i n that work. Consequently, the status of these two taxa i s unclear. Wijk et a l . (1962) noted that Jensen (1939) recognized Hypnum intextum V o i t . i n Sturm and Hypnum ruderale var. intricastum B r i d . as forms of Hygro- hypnum luridum. Again, the reference to Jensen's work i s mistaken, for i f Jensen did discuss these taxa i t was c l e a r l y not i n his Skandinavien Bladmoss-f l o r a . B r i d e l (1827) described Hypnum ruderale var. intricastum. In the absence of the type, the d e s c r i p t i o n i s inadequate to c l e a r l y deal with the name. Simi'l-arly, the de s c r i p t i o n of Hypnum intextum V o i t has been unavailable f o r study and the taxon cannot be e f f e c t i v e l y dealt with. The v a l i d i t y of the taxon i s at best'doubtful. Hygrohypnum luridum var. pseudoehraceum (Roth) Podp. was described as Limnobium pseudochraceum by Amann i n Roth (1915). Amann characterized the taxon as being very s i m i l a r to Limnobium ochraceum and noted i n p a r t i c u l a r the 'exceedingly strong and wide costa. - The plant vaguely resembles Hygro-hypnum ochraceum and seems only to be a coarse variant of H. luridum. The type was examined from S-PA; Amann (1928) described Hygrohypnum subenerve (B.S.G.) Loesk. var. plumulosum. None of the specimens c i t e d by Amann have been a v a i l a b l e f o r study and the de s c r i p t i o n does not allow f o r cl e a r recognition. One feature noted by Amann which i s most unusual f o r a species of Hygrohypnum i s the b i s e r i a t e nature of the leaves. The status of the taxon,is, as yet, unclear. Podpera (1954) however, did reduce i t to a form of Hygrohypnum luridum. 2 4 8 Fig.551 a - j . V a r i a t i o n i n the habit of moist shoots of Hygrohypnum luridum. Scale: 249 250 Fi g . 52 a - q. Variation i n the leaf shape of Hygrohypnum luridum. 251 252 Fi g . 53 a- v. Variation i n leaf shape of Hygrohypnum luridum. Scale: I 1mm I \ \ F i g . 54 - h. Variation i n the c e l l u l a r d e t a i l of the foliage leaves of Hygrohypnum luridum. a - b. Leaf apices c, f - h. Median leaf c e l l s d, e. Marginal leaf c e l l s Scale: a, b; \ 100um l 255 .256 Fig . 55 a- f. Variation i n the alar c e l l s of Hygrohypnum luridum. Scale: I 100"™ I 2 5 7 2 5 8 -t-Fig. 5 6 . Hygrohypnum luridum 259 Exsiccati Examined Allen, Mosses of the Cascade Mountains, Washington # 140 as Hypnum palustre. (MICH, MIN, .NY, USA, TENN) Austin, Musci Appalachiani # 435 as Hypnum palustre. (MICH, NY, UBC, USA) Bauer, Musci europ. etameri. exsiccati. # 2090 as Hygrohypnum palustre. (NY) # 2091 as Hygrohypnum subenerve. (BRNM, NY) Musci eur. exsiccati # 1285a as Hygrohypnum palustre. (BRNM, NY','NICH) # 1285bLas Hygrohypnum palustre. (NY) Brotherus, Musci Turkestanici # 129. (H-BR, LE, MIN as Amblystegium  palustre var. subsphaericarpon) Musci Turkestanici # 256 as Amblystegium palustre var. sub- sphaericarpon (H-BR) Musci Turkestanici # 257 as Amblystegium palustre var. sub- sphaericarpon (H-BR) Bryotheca Fennica # 286 as Hygrohypnum palustre (B, LE) De Notaris, Erbar. Crittogam. I t a l . #906 as Limnobium palustre. (B, NY) Ser. II. # 3 as Limnobium subsphaericarpon. I(UC,- BM) Delogne, Les Mousses de l;Ardenne # 95 as Hypnum palustre. (C) Desmazieres, Plantes Cryptogams de France # 443 as Hypnum palustre. (G) Drummond, Musci Americani # 195 as Hypnum palustre. (CANM, MICH, NY) • Fejfoldy, Flora Hungarica # 423 as Hygrohypnum palustre. (B) Fleischer & Warnstorf Bryotheca Europ. meridion cent III # 298 as-Hygrohypnum palustre var. laxum. (C) Gravet, Bryotheca Belgica # 349 as Hypnum palustre. (G, NY) Grout, North American Musci Perfecti # 118 as Hygrohypnum palustre. (MICH, LE, NY, TENN, USA,-.F) North American Musci Pleurocarpi # 362 as Hygrohypnum palustre. (MICH, MIN, MO, NY, TENN, UC, USA) Hesselbo, Bryophyta Danica Exsiccata # 333 (BP, LE; NICH, CANM) Husnot, Musci Galliae # 494 as Hypnum palustre var. subsphaericarpon. (NY; BM) # 292 as Hypnum palustre. (NY, BM) Jack, Leiner & Stizenberger, Kryptogamen Badens # 96 as Limnobium palustre. (G, NY,BM, BP) Kerner, Flora Exsiccati Austro-Hungarica # 1515 as Limnobium palustre. (G, LE, MO, UC, BP, C) Kopsch, Bryotheca Saxonica # 284 as Hygrohypnum palustre. (MICH) Limpricht, Bryotheca Silesiana # 249 as Hypnum palustre. (B, LE, NY) Lisowski, Bryotheca Polonica Fasc. IX # 266 as Hygrohypnum palustre. (CANM) Fasc. XV # 420 as Hygrohypnum palustre var. hamulosum. (B) Fasc. XXII # 593 as Hygrohypnum palustre (BP, -LE,-»'NICH) Fasc. XXXI # 819 as Hygrohypnum palustre var. tatricum. (B, LE) Fasc. XXXI # 820 as Hygrohypnum palustre var. julaceum. (B, BP, LE., NICH). -Fasc. LXVIII '# 1746'as Hygrohypnum var. julaceum. (LE," NICK) Macoun, Canadian Mosses # 398 as Hypnum palustre. (MICH, MO, USA, C) Canadian Musci # 341 as Limnobium palustre. (CANM) 260 # 356 as Hypnum palustre (MIN, MO, NY, TRTC, UC USA, C) # 357 as Hypnum eugyrium. (MIN) # 493 as Hypnum columbico-palustre. (MICH, MIN, NY, TRTC)• # 527 as Hypnum pseudomontanum. (TRTC) • # 535 as Hypnum dilatatum. (MO) • F l o r a Canadensis # 760 as Hypnum palustre. (TRTC)• Matouschek, Kryptogamen e x s i c c a t i # 2195 as Hypnum palustre. (B, LE, C,. NY) # 1587 as Hypnum palustre var. sub-sphaericarpon (LE, C) Migula, Cryptogamae Germaniae, Austriae, Helvetiae e x s i c c a t i # 272 as Hypnum pal u s t r e . (B, MICH, NY, UBC, C) G. Muller, Westfalien Laubmoose # 123 as Hypnum palustre (BP) Mougeot, Nestler & Schimper, Stirpes Cryptogamae Bogeso-Rhennanae # 521 as Hypnum palustre (G, NY) Petrak, F l o r a Behomica et Moraviae exsiccata II Series L fg.# 1. # 48 as Hypnum palustre var. hamulosum (LE) Pilous, Musci cechoslovenici e x s i c c a t i # 74 as Hygrohypnum palustre. (B) # 117 as Hygrohypnum subenerve. (G) # 237 as Hygrohypnum palustre fo. julaceum. (B) # 279 as Hygrohypnum palustre var. julaceum. (B) #7 33 as Hygrohypnum palustre.(B) # 819 as Limnobium palustre var. tenellum fo. subenerve. (B,C) Rabenhorst, Bryotheca europaea # 294 as Limnobium palustre. (NY, BM, C) # 393 as Hypnum palustre. (NY) _ # 550 as Hypnum palustre var. subenerve. (G,- NY, BM C) # 1347 as Hypnum pal u s t r e . (NY) # 1347b as Hypnum pal u s t r e . (NY) Regensberg, botanischen Gesellachaft, F l o r a e x s i c c a t i Bavarica Bryophyta # 381 as Hypnum pal u s t r e . (B) # 384 as Hypnum subenerve. (B) Schultz, herbarium mormale Cent 12, # 1183 as Hypnum palustre (C) # 1183 b i s as Hypnum palustre (C) Societe dauphinose # 3137 as Hypnum palustre. (G) Wartmen & Schenk, Schweizerische Kryptogamen # 395 as Hypnum palustre. (G, NY) Williams, North American Mosses - Yukon Region # 767 as Hypnum pal u s t r e . (USA) Wilson, Musci B r i t a n i c i # 383 as Hypnum palustre var. subsphaericarpon (G, NY) Zmuda, F l o r a G a l i c i a e # 96 as Hygrohypnum subsphaericarpon (G) Selected Specimens Examined Canada B r i t i s h Columbia Koothey National Park, V e r m i l l i o n R. near V e r m i l l i o n Crossing; Crum ana Sch o f i e l d 5490. (UBC) Vancouver Island: Halbert 6187 261 N. of Fort Nelson along the Alaska Hwy, 58 40 N, 124 42 W; C o r r e l l 12051 as Hygrohypnum palustre. (UBC) Lytton, 8 miles S.; S c h o f i e l d & Boas 17815. (UBC) Armstrong; Wilson, March 1904. (UBC) Bowron R., 25 N. of Bowron Lake; Boas 547. (UBC) Kamloops D i s t r i c t , Kamloops, Jamison Creek; MacFadden 3870. (TENN) Roger's Pass; Macoun 21 July 1890 i n Canadian Musci # 341 (CANM) Spence's Bridge; Macoun 21 May 1889 as Hypnum palustre. (CANM) Yoho Vall e y ; Macoun 478 as H. alpestre. (CANM) Mt. Queest, Cinnemosun Narrows, Shuswap L.; Macoun 27 July 1889 as Hypnum palustre. (CANM) ' K'oe-.tenay National Park, Kimpton Creek below S i n c l a i r Pass; Crum C-65. (CANM) MacLeod's Lake; Macoun 26 June 1875. as Hypnum palustre var. subjulaceum. (NY) P a v i l l i o n Lake; Boas 1960. (UBC) Queen Charlotte Islands, Moresby Is., Kaisoun; Schofield 31112. (UBC) Queen Charlotte Islands, Graham Is., Van I n l e t ; S chofield 32088. (UBC) F r u i t v a l e , Kelley Creek; Jamieson 5580. (UBC) Michel Creek, B.C. Hwy 3 near Sparwood; Jamieson 6065. (UBC) Ten Mile Creek, Slocan Lake; MacFadden 10 June 1926. (UBC) Inver Creek, between Skeena R. and snow patches E. of Prince Rupert; Schofield & Sharp 9/10-118a. (TENN) Wilmer, Lake of Hanging Gl a c i e r ; MacFadden 4376 as Hygrohypnum palustre. (TENN) Ga r i b a l d i P r o v i n c i a l Park, Whistler Mtn Ski Area;<Schofield & Jamieson. (UBC) Alberta' Lundbreck F a l l s , Cbleman-Kananaskis Road; Jamieson 6118. (UBC) : Bearspaw Dam, S, side of Bow R. west"of Calgary; B i r d • 9039. (NY, UBC) Jasper National Park, Miette Hotsprings; Crum & Schofield 4703 (MICH, UAC, UBC) Bow River Watershed, Elpoca Creek along Coleman-Kananaskis Road; Bird's Glenn 13494. (UBC) Waterton National Park, above Anderson Lake; Crum & Sc h o f i e l d 5939. (UBC) Banff National Park, Louise Creek; Jamieson 6190. (UBC) Jasper National Park, Sunwapta Pass Campground; Bird 5232. (ALTA) Manitoba The Rock, on the Hays River; Scoggan 75. (UBC) C h u r c h i l l , Eskimo Point; Crum & Sc h o f i e l d 7155. (MICH) Lower Hays River, York Factory Region, Hudson Bay Lowlands; R i t c h i e 4130. (CANM) Herb Lake V i l l a g e , Wekusko Lake, N. E. of the Pas; Scoggan 102. (CANM) Hansen's Creek, E. of Rennie on Hwy 44; B i r d 3286. (CANM) 262 Saskatchewan Swift Current; Macoun 6 Sept 1880 as Hypnum pal u s t r e . (CANM) Ontario Grey Co., Indi an F a l l s near Balmy Beach; Crum 11352. (TRTC) Bruce Co., Sauble F a l l s ; Moxley 24 May 1936. (5ERTC) Peel Co., Cr e d i t Forks; Cain 1413. (TRTC) Kenora D i s t r i c t , Cedar Lake, N. of V e r n i l l i o n Bay; Cain 4914. (TRTC) Owen Sound; Macoun 28 July 1871 i n F l o r a Canadensis as Hypnum palustre. (TRTC) Thunder Bay D i s t r i c t , lake shore N. End of Simpson Is; Garton 6280. (CANM) Algoma D i s t r i c t , N. end of Bachawana Bay; Sharp CM-631. (UBC) E l o r a , Grand River; Moxley 7 June 1933. (TENN) Manitoulin Island, shores of Manitou Lake: Hermann 16044. (USA) Quebec A n t i c o s t i Island, J u p i t e r River; Macoun 20 Aug. 1883. (UBC) James Bay, Rupert House; Lepage 18969. (USA) Bonaventure Co., Nouvelle River, St. Jean 1 1Evangeliste Colins & Fernauld 3313-AB. (MICH) Lake M i s t a s s i h i , New Quebec; Lepage 4328. (TRTC) St. Rimon Rimouski; Lepage 2828. (TRTC) Pare de l a Gaspesii, S. of St. Anne-des-Monts; Ireland 11170. (CANM) Montmorency River, F a i r y Creek; Macoun 30 June 1905. (CANM) New Brunswick V i c t o r i a Co., Grand F a l l s ; Habeeb 1 July 1943. (UBC, F;) A l b e r t Co., Fundy National Park; Ireland 11565. (UBC) Queens Co., Moser 1889. (CANM) Newfoundland Bay of Islands, Brichy Cove; Waghorne 23. (MO). Lomond R. at i t s i n t e r s e c t i o n with P r o v i n c i a l highway 44. Norris 4584. (HSC) Cataracts P r o v i n c i a l Park, 7 km NW of Colinet; Weber 534 (NFLD) Labrador C h u r c h i l l F a l l s , Bridge Camp Area; Brassard 5178. (NFLD) L'Anse au C l a i r ; Waghorne 8 Sept 1894.. (NY) Yukon Lake LeBarge; Williams 765. (MO) Rancheria River, 60°10'N, 130°08'W.; C o r e l l 12160. (MICH) Dawson C i t y D i s t r i c t , Hunker Creek; Macoun 22 July 1902. (CANM) Haines Highway, 83 miles NW of Haines, Alaska; Hermann 21848. (CANM) Francis Lake, on Money Creek; Jamieson 1976. (UBC) North West T e r r i t o r i e s . Ellesmere Island, Head of Tanquary Fjord; Brassard 1614. (CANM) V i c t o r i a Island, Kaskyak River, Minto I n l e t ; Wynne 18860. (NY) Great Bear Lake, E. end of McTavish Arm, v i c i n i t y of Eldorado Mine; Steere 10070a (NY) Campbell Lake, Scotter 9742 (C, as Hygrohypnum alpestre.) United States Alaska Skagway, Williams 27 Aug. 1899 i n North American Mosses-Mukon Region # 767. (USA) 263 Mount McKinley Region, Garner, Bragstad Creek; Sherrard C-18. (USA) Anchorage-Seward Highway, McHugh Creek Campground; Sharp 14 June 1971. )TENN) Brooks Range, Sik-Sik-Puk River, Gorgeous Gorge, 30 miles-W. of Anaktuvik Pass; Spatzman 15 Aug. 1951. (NY) Takhin Valley; Krause 20 July 1882. (NY, as Hypnum krausei; isotype ) Brooks Range, S. of Cape Thompson, Ogotoruk Creek; Steere 63-652. (NY) Brooke Range, Endicott Mountains, SW of Chandler Lake; Steere 18333. (NY) Brooks Range, Fr a n k l i n Mountains, . Schrader L. Peters L. area; Steere 18926a. (NY) Washington King Co., Green River Gorge, E. of Black Diamond; Ireland 9606. . (CANM) Upper Va l l e y of the Neaqually; A l l e n 28 June 1898 i n Mosses of the Cascade Mountains, Washington # 140. (USA, CANM) Olympic Peninsula, Mouth of Sekim River; S v i h l a 703. (MICH) C a l i f o r n i a Sequoia National Park, Halstead T r a i l ; Degener & P e i l e r 16914. (MO) New Mexico Hermit's Peak; Arsene 18479. (USA) Cumber's Pass; Vreeland 31 Aug. 1900. (NY) San Miguel Co., Pecos V a l l e y Holy Ghost Creek; Studhalter & Man 3089 (COLO) Taos Co., Angosturo Creek, Tres Ritos; Studhalter & Man 3258 (COLO) Arizona Coconine Co., West Fork of Oak Creek Canyon; Dunn 417. (?) Idaho Custer Co., Sawtooth Wilderness Area, Forks of Baron Creek; Morton 8537. (USA) Kootenai Co., Lake Pend d ' O r e i l l e ; Leiberg June 1889. (NY) Utah S a l t Lake Co., Brighton; Darker 5897. (MICH.) Marysvale, F a l l s above B u l l i o n Creek; Jones 5899. (MO, UC) Montana Linco l n Co., Kootenai River, Kootenai F a l l s Overlook, 7 miles E. of Troy; Hermann 22481. (TENN) Flathead National Forest, Echo Lake; Kaufman July 1928. (TENN) Park Co., S i l v e r Gate, Wyoming Creek; Conard 25 Aug. 1953. (CANM, TRTC) Columbia F a l l s ; Williams 24 July 1895. (C, MO) St. Ignatius, near Mary's Lake; Frye 2137. (CANM) Gl a c i e r National Park, SW shore of Bowman Lake; Hermann 18017. (CANM) Carbon Co., SW of Red Lodge, T r a i l to F a l l s of Basin Creek; Lawton 2156. (CANM) Wyoming Carbon Co., Elk Mtn,; Gooding 21 Aug." 1901. (MIN, USA) 264 Big.Horn Mountains, Granite CrEek; Whitehouse 25916. (USA) Albany Co., Libby Creek; Porter 1536. (TENN)' Park Bo., Absaroka Range; Kiener 4047. (MICH) Yellowstone River; Knowlton 10 Aug. 1888. (USA)-Albany Co., Medicine Bow Mountains, 9 miles W. of Centinal Hermann 17692. (CANM) Beartooth Mountains; shores of Beartooth Lake; Welch 16600. (CANM) Colorado N La P l a t a River; Baker, Earle & Tacey 20. (USA) Manitou, Ruxton Creek; Jewett 18 July 1910. (USA) • Col l e c t e d mostly within 100 miles of Canon Ci t y ; Brandegee ' 1874 - 1878. (USA) Gunnison Co., v i c i n i t y of Gothic, East River Valley; Welch 9096. Larimer Co., Rochy Mountain National Park, 7 miles SE Chambers Lake; Hermann 26783. (UBC) Minnesota Cook Co., v i c i n i t y of Grand Marais; Holzinger 16 July - 7 Aug. 1902. (MIN) Cook Co., Schroeder, Cross River Gorge; Olson 761. (CANM) Michigan Ontanogon Co., Porcupine Mountains State Park, T r a i l to Buck-shot Cabin; Ireland 5214. (USA) Keweenaw Co., G r a t i o t R., 2 miles W. of C l i f f ; Hermann 16389 :<USA) Alger Co., Miner's F a l l s ; Sharp 22 July 1955. (USA) I s l e Royale National Park, S c o v i l l e Point; Van Dyk Aug. 1955. (USA) Cheboygan Co., M i l l Creek; V i t t 304. (ALTA) Marquette Go.,.Huron Mountains, C l i f f River, Nichols Aug. 1934. (NY) Wisconsin B a y f i e l d Co., Near Herbster on Lake Superior; Cheney 6913. (TRTC) Ohio Ottawa Co., South Bass Island; Schnooberger 3586. (USA) New York Watkins; Austin 17 July 1874 (NY) Herkimer Co., Newville; Austin 1868. (NY) Cayuga Lake Basin, Foot of Island F a l l , F a l l Creek; Dudley 25 Nov. 1882. (NY) New Jersey. Sussex Co., West Vernon; Austin Sept 1867. (NY) Vermont Caledonia Co., Peacham; Blanchard 5 Nov. 1885. (USA) New Hampshire Bekknap Co., G i l f o r d , Mt. Belknap;. Carter 5 Sept 1904. (USA) West V i r g i n i a Mingo; Gray M-1408. (TENN) Uffington; Herrod 20 June 1930. (USA) Guatamala Dept. of Huehuetenango, Taquia; Vogel B-9009. (NY, TENN) 265 Greenland Qroge Peninsula, Inukavsait Fjord, Sagdliaruseq; Holmen 17054. (NY) Scoresby Land, Mestersvig, Blyminen; Holmen 18045. (NY) Great B r i t a i n Scotland Sutherland Co., near Inchnadamph; Crundwell 12 June 1951.(G) Wales Black Mountain, Brechnoch, N slopes of Darenlwyd; L i f l i n 18 May 1959. (FLAS) Northern Ireland B e l f a s t ; Stewart 12 May 18-7. (NY) Faroes StjzimjzJ, Gjoven at Vestmannahavn; Jensen 9 June 1896. (NY) Iceland S . - I c e l . , Rangarvallasjsta, Drangshlid; Johannson 14 July 1965. (FLAS) Denmark Jutland, bei Bjornsholm; Jensen i n Bryotheca europaea # 393. (NY) Zealand, Lake Fureso; Hesselbo 8 July 1903 i n Bryophyta Danica ' E x s i c c a t i # 333. (S-PA) Bornholm, Bobea; Jensen 2-4-1882. (H) Netherlands. W. E. plas; Wasschen 29 June 1956. (GRO) Dordrecht; van der Sande Lacoste. (GRO) Belgium Dinant (Namur); Gravet i n Bryotheca Be l g i c a # 349. (G) France Chambery Sabaudiae, Cascade de Coux; Paris 10 July 1861 as Hypnum  palu s t r e . i n Bryotheca europaea # 550. (G) V i l l a r e de.Lans, Isere; Ravaud IN Societe dauphinose # 3137. as Hypnum pal u s t r e . (G) Haute Savoie, Foret de l a g l a c i e r e au Mont Brezon; Bernet 29 July 1883. (G, S-PA) Blanche, au Mont Blanc; l e g . ?. (B, accession # 7720/345) 7972 Haute Garonne, Devesoir du Lac Vert pres Luchon; Husnot as Musci G a l l i a e # 592. (S-PA) Montauban; Lange 7 Sept 1857. (S-PA) Germany Allgau, Hindelang, Wildbachtabel b e i Oberdorf; Bornmuller 26 Aug. 1922. (B) Krahenberg; Winter A p r i l 1902. (B) Fichtelgebebirge, b e i der Ruine Waldstein; Familer & Schwab Aug 1903 as F l o r a E x s i c c a t i Bavarica; Bryophyta # 384. (B) Mark Brandenburg, Potsdam; Benkert Nov. 1960. (B) Ruisse, Walkenreid; Loeske 1/6/1903. (B) Ruhland; Moenkemeyer J u l i 1910. (NY) Waren b e i Mwritz; Struck. (S-PA) Bayern, Partenkirchen; Suse March 1916. (S-PA) Wurtemburg, Alpirsbach; Walde 1897. (S-PA) Rheinland, Merzig a. d. Saar; Winter. (S-PA) Rheinland, Bensberg (near Koln); Schlueger. (S-PA) 266 Hessin, Eberstadt; l e g . ?. (S-PA) Baden, Heidleberg; Arschoug Mai 1861 (S-PA) Thuringer, Jena; Roell 27 July 1871. (S-PA) Au s t r i a Neider Oestereich, Schrattenstein, S t i x t e n s t e i n ; Redinger 28 June 1931. • . Neider Oestereich, Schneeberg, A l p e l l e i t e n zwischen Baumgartnerhaus-Lackerboden; Redinger 19 July 1931. (B) Dachsteingebeites; Morton 1923. (B) T i r o l i a c e n t r a l i s , i n v a l l e Gschnitzel; Kerner i n F l o r a E x s i c c a t i Austro-Hungarica' # 1515. Voralberg, Walscatal Aufsberg zwei Fleu; Bornmuller 30 July 1936. (B). Neider Oestereich, Obersee b e i Lunz; Redinger 16 June 1930. (B) Switzerland S i l v e r e t t a Gruppe; Bornmuller 26 July 193 2. (B) In den Arve bei Genf; Bernet J u l i 1863 i n Schweizerische Krypto-gamen # 395. (G) Via.Mala; Reuter Aug. 1854. (G) Neuchatel; Bruch. (S-PA) Zurich, Huntwangen; Frymann Feb 1893. (S-PA) Zermatt; Husnot i n Musci G a l l i a e # 292 (S-PA)-Gemhi Pass; Renisch. (S-EA) Lugano, Monte Are; Kindberg 27 June 1892. (S-PA) I t a l y C a r r a v e l l a (Ganzeglio); F l e i s c h e r 23 July 1895. (B) D i n t o r i S e r r a v i l l e a l i a S c r i v i a ; F e r r a r i 1862. i n Erbar, Crittogam. I t a l . # 906. (B) Lig u r i e n , im Bogo b e i Rapallo auf kalk; F l e i s c h e r Aug. 1896. i n Bryotheca Europ. meridion Cent. I l l # 298. (B) T a r v i s i n a , ad flumen, Plavino; Saccardo. (S-PA) Lago d'Como; Leg. ?. (S-PA) Czechoslovakia Moravia, Mariental ad therman T e p l i t z pr. Mahr-Weisskirchen; Matouschek i n Kryptogamen e x s i c c a t i # 2195. (B) Slovakia, Mont Mala Fatra, prope Krasnany; Pilous May 1935. i n -Musci cechoslovenici e x s i c c a t i # 74. (B) Bohemia, Trutnov, prope Volanov; Pilous June 1949 i n Musci cechoslovenici e x s i c c a t i # 819. (B) Slovakia, Montes Belske Tatry, prope Zdearska V i d i a ; Pilous Aug. 1947. i n Musci cechoslovenici e x s i c c a t i # 279. (B) Marienbad (=Marianske Lazne); Suse 11/9/1915. (S-PA) Poland Tatry Zachonie, Montes Tatra O c c , v a l l i s Dolina; Lisowski 8 May 1956 i n Bryotheca Polonica Fasc. XXXI # 820. (B) Mons P i l s k o , (Beskidi A l t i ) , t o r r e n t i s Cebula; Lisowski 5 May 1957. i n Bryotheca Polonica.'Fasc. XXII # 593. (S-PA) Gleiwitz i n Oberbflnfinu (? s p e l l i n g ) ; Kabbatk. (S-PA) Elbing, Vogelsanger Wald, Kalmuss 1895. (S-PA) Hungary Comit. Borsod., v a l l i s Garadna-volgy supra Omassa; Boros 16 Oct. 1959. (B) Comit. Zala, lacus Balton ad Tihany; Boros 4 A p r i l 1957. (B) 267 Comit. Esztergom, v a l l i s Ramszaka dek prope Domos; Boros 7 Aug. 19^49. (BP) Comit Veszprem, v a l l i s Zurokvolgy prope pag Bakouykuti; Vajda 30 May 1954. (BP) Comit, Psst., montes Nagyszensas prope pag Nagykovasci; Vajda 16 Oct. 1955. (BP) Comit. Heves, montes Tasko prope pag Parad; Vajda 27 May 1952. (BP) Rumania Carpat, merid., Comit, Csih, v a l l i s Uzvolgy prope pag Csikszent-mahtom; Vajda 28 Aug. 1970. (BP) Carpat, merid., v a l l i s Radesului prope Gura Api, montes Retyezat; Vajda 12 July 1968. (BP) Banat., r i v i Csernapatak, ad Hetforras prope pag B a i l e Herculane; Vajda 7 Aug. 1967. (BP) Turkey Prov. Rise, D i s t r i c t Hemsin, Ortakoy-Cat; Davis 21311. (C) Norway Nordland, Sorfolden; Nyman 19 Aug. 1899. (S-PA) • Troms, f j l k e Tronso; A r n e l l 11 J u l u 1891. (S-PA) . Sor-Trondlag, Trondherim; A r n e l l Juni 1869. (S-PA). Trondfjeldet; Kindberg 22 July 1897. (S-PA) . Gudbrandsdalen; Zetterstedt'25 June 1858. (S-PA) Dovre; Hartman 1872. (S-PA) Hordaland, Hardangervidda stras o om Dyrskar v i d vagen mellan Oslo och Haugesund; S t r i d v a l l 4 Aug. 1970. (S-PA) Sweden Skane, V i n s l o f sn i baken N v i d landvagen 2 km USV on Lommarp; -Johansson 10/7/1916. (S-PA) Bleckinge, Sisseback, f r a steu; Medelius 4/9/1922. (S-PA) Halland, G Karujis kyrka; F l o r i n 15 June 1923. (S-PA) Smaland, Jonkoping Torpa; Arven 15 Sept 1896. (S-PA) Gotland, Lummalunda; Jaederholm 1 July 1923. (S-PA) Ostergotland, Omberg; Mosen 12 Sept 1871. (S-PA) Vastergotland, Skovde, Havstena, Tomtangen; Hulphers J u l i 1930. (S-PA) , Bohuslan, Fishebackskil ogavdun; Hulphers Aug. 1927. (S-PA) -Salsland; Bergstrom 16 Sept 1913. (S-PA) Narke, Karlsluund;.Weldheim 26 May 1923. (S-PA) Sodermanland, Vardinge sn Sjunda; F l o r i n 4/9/1927. (S-PA) Uppland, Upsala, Krasnbo; Jaederholm' 1888. (S-PA) Vastmanland, Grythytte Skatviken; Stenholm 6/8/1925. (S-PA) Varmland, Persberg; Larsson 9/6/1914. (S-PA) Dalarne,.par Boda, Osmundsberg, A r n e l l 17 Aug. 1896. (S-PA) Gastrikland, Valbo; Hartman June 1858. (S-PA) Medepad, Torp sn Johannisberg; Huss 1882. (S-PA) Harjedalen, paroec Tannas Ljusnedal; Ostmann 19 June 1905. (S-PA) Jamtland, Offerdals sn Hallberget; F l o r i n 25 June 1944. (S-PA) Lycksele Lappmark, Tarna; Hulphers 15 July-1940. (S-PA) Angermanland, par Tasjo Tasjoberget; A r n e l l 14 July 1894. (S-PA) Lule Lappmark, Jikkmokk; Nyman Aug. 1893. (S-PA) Laponia Tornesnis, Roukoajokk (Jukkasjarvi); Jaederholm 27 July 1912. (S-PA) Lapponia Tornensis, Abiskojokk; Jaederholm 12 July 1917. (S-PA) 268 Soviet Union Caucasus, in f l . Rion pr. Eltsevi; Brotherus 10 July 1877. (NY) Alt a i Mountains, Katung pr. Techeposch; Grano. (H-BR) Siberia, Yamarovka; Mikkvo 24 June 1904. (H-BR) Tomsk District, Tomsk Junge; Matoejeff 12 July 1912. (H-BR) Siberia, Jenesei, Hantai; Sahlberg 1876. (H-BR) Siberia, Jenesei, Tostoinis; Arnell. (H-BR) Siberia, Lena, Kamachsur.; Nilsson-Ehle 6 Aug 1898. (C,S-PA) Sib eria, Lena, Balagnach; Nilsson-Ehle 15 July 1898. (C, LE) Siberia, Jenesei, Plachino; Arnell 22 July 1876. (C, S-PA) Karelia ladogensis, Par Svistamo, Kaaherjoki Laynavaara; Kotilainen 22 Sept 1926. (H, S-PA) Prov. Uchta, Archangelsk; Liskendrath June 1885. (H) Prov. Perm; Keller. (H) Rossia Bor. porp Vologda; Dohle 1/7 1907'. (H) Irkutsk Di s t r i c t , Verzholensk in valle f l . Tachikan; Kusenezou Jenesei District, Turuchansch Chantaish; Kusnezow at Rever-datto 7 July 1914. (H-BR) Pamir in angustatis Chargusti; Paulson 4/9/ 1898. (H-BR) Al t a i Tschemal; Verestchagin. (H-BR) Al t a i , ad f l . Mena; Krylow. (H-BR) Amur, Tukuringra an Ufer des Saja; Kuseneva 9/7/ 1915. (H-BR) Jakutsk, Jenkovshi spitze; Kusenova. (H-BR) Semiryelschensk, Almatinka minor props Vjernoyi; Regal 20/3/ 1876. (H-BR) Terskei Alatau, f l . Dschuka; Brotherus 5 Aug 1896 in Musci Turkenstanici #130. (H-BR) Kungei Alatau, as fontes f l . Koissu; Brotherus Aug 1896 i n Musci Turkenstanici # 256. (H-BR) Thian Schan (=Tien Shan) Mtns., ad. f l . Narinhol (=Naryn) R.; Brotherus 25 July 1896. (H-BR) Siberia, Ust ' Kut, in valle flum Lena; Nilsson-Ehle 4 June 1898. (S-PA) Jenesei, Nischnaja Tunguska; Arnell 14 July 1876. (S-PA) Kashmir Karakorum Range, upper end of the Hushe Valley, Atosar Valley; Webster & Nasir 6090. (TENN) Lind Valley near Sonamarg; Duthie 17 Aug 1893. (H-NR) Balliston, by water course W. of Dras; Duthie 24 Aug 1893. (H-BR) Gulmarg; Duthie 8 Jan 1892. (H-BR) Indian Uttar Pradesh, Kimaun, Kulti Valley; Duthie 7 Sept 1894. (H-BR) Tibet Kargall, Darass Valley; Khan 26 June 1901. (H-BR) Finland Kuusamo, rivulo Kulmakkapuro; Hallstrom 18 July 1911 in Bryotheca Fennica # 286. (B, LE) China Interior provincia, Schen-si sept, in medio monte Kuan-tou; Giraldi 1894. (G) Yunnan Prov., head waters of the Mekong R.; Handel-Mazetti #1565. (H-BR) Setchwan Prov,, In montium Daliang-schan (t e r r i t o r i Lolo), ad orientum urbis Ningyuen regione calide temperata ad rivulum prope vicum Sikwai; Handel-Mazetti # 391. (H-BR) Japan Tshihau Prov. Yubari Mtn; Yasuda 518. (H-BR) Spitsbergen, King's By D i s t r i c t ; A r n e l l & Mortensson 26 July 1956 270 Hygrophypnum alpestre (Hedw) Loesk., Verh. Bot. Ver. Brandenburg 46: 198. 1905. Neotype: "nolle"; from Swartz herbarium: annotated by Nyholm (S-PA). . ' Hypnum r i v u l a r e Sw., Disp. syst. muse. Suec. 1799 - not seen - c i t e d from Hedw. 1801 & Broth, 1924 nom.; i l l e g . horn. Hypnum alpestre Hedw., Spec. Muse. 247. 64f. 1-4. 1801 Hypnum molle var. alpestre (Hedw.) Hamp., Flora 20:274. 1837. Limnobium alpestre (Hedw.) Schimp., Bryol. Eur. 6:68. 1853. Figure 577 not included. Amblystegium r i v u l a r e (Sw.) Lindb, Musci Scand. 33. 1879. nom. i l l e g . Calliergon alpestre (Hedw.) Kindb., Canad. Rec. Sc. 6(2): 72. 1894. Hygrophypnum r i v u l a r e (Sw.) Broth., Laubm. Fennosk. 500. 1923. nom. i l l e g . Plants usually s o f t , rarely somewhat s t i f f , usually forming loosely woven patches or t u f t s , often e a s i l y fragmenting. Color variable, yellow or yellow-green with or without rusty mottling above, older extremities d i r t y brown, reddish-brown or reddish-black, rarely green or yellow-green throughout. Stems (1) 2-4 (9) cm long, prostrate or ascending near the apex; stems f o l i o s e throughout or denuded toward the base or clothed i n persistent leaf bases, frequently clogged with s i l t . Branching i r r e g u l a r , branches usually ascending. Stem cross sections revealing 2-3 concentric rows of brownish, thick-walled c o r t i c a l c e l l s ; medullary c e l l s larger, thinner walled, hyaline, becoming discolored and sometimes incrassate with age; central strand well developed. Rhizoids infrequent, 2 7 1 a r i s i n g on young stem or branch segments from the bases of ventral leaves, generally absent or obscured i n the older extremities. Leaves variable, closely spaced and julaceous, sometimes spreading, especially i n some young stem or branch t i p s , spreading leaves sometimes shrinking l a t e r a l l y and twisting s l i g h t l y upon drying, otherwise changing l i t t l e from the wet to the dry condition; leaves oblong to oblong lanceo-l a t e ; straight, never fa l c a t e ; (0.9) 1.4-1.6 (1.9) mm long x (0.4) 0.6-0.7 (0.9) mm wide; deeply concave, almost boat shaped i n the apex, generally tumid julaceous; apex acute to s l i g h t l y obtuse, becoming reflexed as a squarrose apiculus, apiculus generally worn away i n older leaves; margins entire or uneven i n the apex, narrowly recurved, especially i n the upper 1/3 and the apex; shortly and narrowly decurrent at the point of insertion costa variable, usually long and double with one arm reaching midleaf, less frequently single to beyond midleaf or short and double, i n a l l cases slender and f a i n t . Aerolation uniform, median leaf c e l l s long l i n e a r flexuose (55) 65-90 (105) um long x 5-6 um wide, apical c e l l s vary with the shape of the apex, usually longer i n acute apices c e l l s toward the base becoming shorter, somewhat wider and more incrassate; p i t s variable, few to none; alar c e l l s s l i g h t l y enlarged, rounded quadrate or short rectangular, thick-walled c e l l s , becoming discolored with age, sometimes excavated. Plants autoicous; perigonial leaves ovate with a small t i p , concave imbricate, ecostate; outer and middle per i c h a e t i c a l leaves ovate to ovate lanceolate, ecostate, squarrose i n the upper half ; inner p e r i -chaetial leaves l i n e a r lanceolate to lanceolate, to 2. mm long, str a i g h t , p l i c a t e , margins entire or sometimes toothed i n the apex; costa f a i n t and slender, double to midleaf, single to midleaf or absent. 272 Seta 7 to 16 nun long, smooth, reddish brown; capsule t y p i c a l f o r the genus. Peristome t y p i c a l f o r the genus; annulus composed of two rows of c e l l s ; inner peristome with 3, sometimes 2, f i n e l y p a p i l l o s e , s l i g h t l y appendiculate c i l i a between adjacent segments; spores 10 to 18 um., usually 12 to 16, f i n e l y p a p i l l o s e , dusky: yellow. Among the species of Hygrohypnum, H. alpestre i s most e a s i l y diag-nosed by i t s narrowly recurved, squarrose l e a f apex (Fig. '57h). Tough obscured i n s l i d e preparations f o r the compound microscope, the squarrose apex i s e a s i l y seen with a d i s s e c t i n g microscope or a hand lens. One must examine young stem or branch leaves f o r the squarrose apex for the apex i s frequently worn away i n older leaves. Other useful characters are the boat shaped concavity of the leaves, the oblong to oblong lanceolate leaves (Fig. 57 a - g,..i -;.k) the normally slender and long double costae, the uniformly long median le a f c e l l s (Fig. 58 c and d) and the rounded quadrate a l a r c e l l s (Fig. 58 f - h ) . The l e a f concavity i s very deep, but does not extend a l l the way to the apex. Instead, the concavity ends shortly below the apex, thus deliminting a planar zone j u s t below the squarrose apiculus (Fig. 57e). The upper 1/3 to 1/2 of the le a f thus appears boat shaped. Normally the stems of H_. alpestre are strongly tumid-julaceous (Fig. 57h) . Occasionally the leaves are loosely spreading. Of a l l the Hygrohypjia, H_. alpestre remarkable e x h i b i t s a very uniform median le a f a r e o l a t i o n . The median l e a f c e l l s do not have unusually short or unusually long c e l l s scattered through an otherwise uniform median a r e l a t i o n as do some species. In the past, Hygrohypnum alpestre has been confused with H_. molle, 2 7 3 H. luridum and H. eugryium. For a comparison of H. alpestre and H. molle, see the discussion under the l a t t e r species. The following chart w i l l point out the pertinent di f f e r e n c e s between the remaining three species. Leaf shape H. alpestre Oblong to oblong lanceo-l a t e . H_. luridum Lanceolate to oblong lanceo-l a t e . H_. eugyrium Lanceolate to oblong lanceolate Leaf apex Acute, with a squarrose, r e -curved apiculus. Acute, s t r a i g h t , secondarily apiculate by i n r o l l e d margins. Acute, s t r a i g h t , one or both margins i n r o l l e d . Leaf symmetry Straight. S t r a i g h t or f a l c a t e . Falcate or s t r a i g h t . Concavity Deeply concave, boat shaped i n the apex. Plane to shal-lowly concave. Concave. Leaf a t t i t u d e Tumid-jula-ceous through-out. Julaceous to spreading. Imbricate to spreading. Costa Usually slender, long and double. Strong and s i n g l e or short and double, of equal frequency. Usually short and double f a i n t . Alar c e l l s Quadrate to s l i g h t l y enlarged. Quadrate short, rectangular, r a r e l y enlarged or i n f l a t e d . Quadrate to short rectangular, i n f l a t e d . The only forms of Hygrohypnum luridum with which H. alpestre can be e a s i l y confused are the s t r i g h t leaved, julaceous ones. Here, the two taxa can be r e a d i l y separated by the squarrose l e a f apex of H. alp e s t r e . 274 On rare occasions a few workers have confused E. eugryrium with H. alpestre. These two taxa may be separated most ea s i l y by the squar-rose leaf apex of II. alpestre. I t i s also worth noting that the known di s t r i b u t i o n s of the two taxa are not sympatric. In the type description Hedwig (1801) based Hypnum alpestre on a Swartz specimen from alpine Norway. At the present time there are no spec-imens of Hypnum alpestre i n the Hewwig herbarium. At S-PA there are two specimens of Hygrohypnum alpestre i n the Swartz herbarium, both of which are equally representative of the species as understood here. One specimen bears no other data other than the penciled name "molle" and a Nyholm annontation l a b e l c a l l i n g the plant H. alpestre. The second specimen i s mounted on a very fibrous paper and bears a few notes concerning other l i t e r a t u r e c i t a t i o n s . This second specimen i s selected as the neotype. Warnstorf (1915) described Hygrohypnum alpestre var. scorpioides. The type of t h i s variety has not been available for examination. The description points out three characters that are unusual for the species, i f i n fact the variety i s H_. alpestre. The leaves of the variety are described as being up to 2.5 mm. long. This c l e a r l y exceeds the leaf size for the species as determined by the present study. The leaves of the variety are further described as being "secundo-imbricata." The leaves of the species have never been observed to be secund. In other species, that leaves be str a i g h t , secund or falcate has been shown to be v a r i b e l . The stem and branch t i p s are always s t r a i g h t , though they may be " c a t k i n - l i k e " or hakenformig. The status of the variety i s unclear and certain reservations are j u s t i f i e d . 275 Fig . 57 a - k. Variation i n the leaf shape and the habit of the shoot of Hygrohypnum alpestre. a - g , i - k . Variation i n leaf shape, h. The habit of a moist shoot. Scale: a - g, i - k; I 1mm 1-h; The shoot i s approximately 1 cm long 276 277 Fig. 58 a - h. C e l l u l a r d e t a i l of the foliage leaves of Hygrohypnum  alpestre. a, Leaf apex. b, e. Marginal leaf c e l l s . ' c, d. Median leaf c e l l s , f - h. Alar c e l l s . Scale: a - e; I ' 100um I f - h; I I 100um | 279 4-F i g . 59. Hygrohypnum alpestre 2 8 0 E x s i c c a t i Examined Bauer, Musci europ. exs. # 643. (BRNM, NY) # 1 2 7 7 . (BRNM) Husnot, Musci G a l l i a e # 750 as Hypnum alpinum. (S-PA) Rabenhorst, Bryotheca europaea #913. (NY) Selected Specimens Examined Canada B r i t i s h Columbia Lake Lindeman; Williams 27 May 1898 as Hypnum al p e s t r e . (NY) Manitoba Seal River, W. of Great Island; Ritchie 1946. (CANM) Ontario Thunder Bay D i s t r i c t , Oskondaga River NNE of Shabaqua Station, Goldie Township; Garton 10685 as Drepano- cladus revolvens. (CANM) Thunder Bay; Macoun July 1869 as Hypnum molle. (MO, NY) Current River; Macoun 19 July 1869. (MO) Labrador C h u r c h i l l F a l l s , Bridge Camp Area; Brassard 5523. (NFLD) North West T e r r i t o r i e s Great Bear Lake, Port Radium, v i c i n i t y of the Eldorado Mine; Steere 10246. (CANM) Campbell Lake, 68° 08' N, 133° 27' W; Scotter 9742. (C) Hudson's Bay, Belcher Islands, Tukarak Is., near Long Lake; Dontt #355. (MICH, NY) Queen E l i s a b e t h Islands B a f f i n Island, Head of Clyde I n l e t , Falcon River, Wynne-Edwards 9285. (CANM, NY) United States Alaska Brooks Range, Endicotte Mountains, SW end of Chandler Lake; Steere 18252a. (NY) Brooks Range, northern slope of the DeLong Mountains, v i c i n i t y of Noluck Lake; Steere 63-380. (NY) Greenland Godhavn; Berggren 1870. (NY, S-PA) Martlek; Berggren 1870. (S-PA) Jacobshaven; Berggren 1870. (S-PA) Ritenbenk; Berggren 1870. (S-PA) Svartenhuk Peninsula, Umiarfik Fjord, Amitsoq; Holmen 12002. (CANM, LE, NY) Christianhalb; Holmen 12066. (NY) Scoresby Sund, Sydlap; Holmen 18461. (NY) Geographical Society Islands; Holmen 18634. (NY) Renland, Rypefjord; Holmen 19166. (CANM, NY) Iceland E. I c e l . , E g i l s s t a o i r , Eyvindara; Johannsson 12 Aug. 1967. (FLAS) 281 Bear Island Mt. Misery; Berggren 1868. (S-PA) Spitzbergen Kobbe Bay; Berggren 1868. (MICH, S-PA) Sweden Halsingland, Abra, Hofsatter; Collinder 17 July 1878. (S-PA) Harjedalen, Storsjo, Lyungdalsforsen; Florin 10 July 1931. (S-PA) Jamtland, Frostvikens; Florin 13 Aug 1925. (S-PA) Nordbotten, Kiruna Katterjaure; Hulphers 14 July 1944. (S-PA) Asele Lappmark, Vilhelmina; Moller 20 July 1914. (S-PA) Lycksele Lappmark, Tama, N. Storsf j a l l e t ; Stenholm 16 July 1924. (S-PA) 1 ^ Pite Lappmark, Arjepluog; Moller 12 July 1918. (S-PA) Lule Lappmark, regio Sarjekensis; Jensen & Arnell 3 Aug. 1902. (S-PA) Torne Lappmark, Abisko; Hulphers 21 July 1941. (S-PA) Norway Kongswold; Kindberg July 1885. (S-PA) Lomseggere; Bryhn July 1879. (S-PA) Finmarken, mellan Nergaan ob f j e l l e t Aglappen; Maalseludalen; Holmgren 28 July 1868. (S-PA) Norlands, am Salten Bejeeren; Hagen 3 Aug 1894. (S-PA) Tromso, amt Nordreisen; Arnell 29 Aug 1891. (S-PA) Gausta; Jaederholm, July 1895. (S-PA) Finland N. E. Le Poroeno, Vallinkorva; L. & H. Roivainen 1 Aug 1961. (BP, UAC) Soviet Union Siberia, Yakutia, Lowlands of the Lena River, Buchta Tiksi; Kildjushebski 12 Aug 1955. (LE) Kola Peninsula, Khibiny Mnt.; Shelyakov 1768a. (LE) Tilajak, Konjakovsk Serebryank Mountaints, Headwaters of the Iova River; Gorchakovski 9 June 1953. (LE) Middle Urals, Denezhkin Kamen; Teklemushev 10 July 1928. (LE) Novaya Zemlya, Guba Krestova; Brotherus 9-10 Aug 1901. (LE) Turukhansk District,, Jenesei Inlet, Dudinka River, Matvjev 253. (LE) Siberia, Jenesei, Duninka; Arnell 7 Aug 1876. (C,NY) Lapponia ponojensis; Ponoj; M. Brenner 17 July 1863. (LE) 282 Hygrchypnum polare (Lindb.) Loeske, Verh. Bot, Ver. Brandenburg 46: 198. 1905. Lectotype: Insulae Spetsbergensis, Wahlenbergs Bay. Leg: A.J. Malmberg. 1861. (S-PA) Hypnum polare Lindb., Oefv. K. Vet. Ak. Foerh. 23:540. 1867 Hypum polare var. pseudostramineum Lindb., Osfv. K. Vet. Ak. Foerh. 23:540. 1867. Holotype: H-SOL, Spitzbergen, ad Kobbe Bay. Leg. A.J. Malmberg, 1861. Amblystegium polare (Lindb.) Lindb., Musci Scand. 33. 1879. Hypnum polare var. laete-virens Ekstr., Bot. Not. 1880:198. 1880. nom. nud. Hypnum palu s t r e var. polare (Lindb.) Husn., Muse. G a l l . 411 1894. C a l l i e r g o n polare (Lindb.) Kindb., Eur. N. Am. Bryin. 1:82. 1897. Hypnum polare var. falcatum Bryhn, Nyt. Naturvid. 40:24. 1902. Hygrohypnum polare (Lindb.) Broth., Nat. P f l . 1(3):1041. 190 . Amblystegium e h l e i Am., Ark. Bot. 13 (2): 74-75 f.3. 1913. Lectotype: S i b e r i a , Lena, Kumashsur, 70° 30' N; Nilsson-Ehle 1898. (S-PA) Hygrohypnum ehleL (Am.) Broth., Trav. Mus. Bot. Ac. Sc. Petrograd. 16:42. 1916. Hygrohypnum polare var. falcatum (Bryhn) Broth., Laubm. Fennosk, 499. 1923. Hygrohypnum palustre var. polare (Lindb.) Moenk., Laub, Eur. 737. 1927. Hygrohypnum palustre var.. e h l e i (Am".)- Grout, Moss F l . N . Am. 3:88. 1931. Hygrohypnum polare fo. falcatum (Bryhn) Jen., Skand. Bldmfl. 464. 19 39. 2 8 3 Hygrohypnum polare var. pseudostramineum (Lindb.) Podp., Consp. 573. 1954. Hydrohypnum luridum var. e h l e i (Arn.) Wijk et Marg., Taxon 7:289. 1958. Names treated elsewhere as synonyms, but for which the l i t e r a t u r e was unavailable f o r assessment during t h i s study. Hypnum polare var. hamatum Kindb., Bib. K. Svensk. Vet. Ak. Handb. 7(9):183. 1883. Limnobium polare (Lindb.) C. Jens., Medd. Groenland 3:333. 1887. Amblystegium polare var. falcatum (Bryhn) Moell., Bot. Not. 1907: 144. 1907. Amblystegium polare var. pseudostramineum (Lindb.) Hess. Medd. Groenland 43 :179. 1911. A i Plants v a r i a b l e , forming densely woven, appressed t u r f s or l o o s e l y woven patches. Color golden-yellow to yellowish-green, r a r e l y bright-green. Stems (1) 2-6 (13) cm. long, p r o s t r a t e , ascending or erect. Unbranched or i f branched, then u s u a l l y from near the base or the main stem, l e s s commonly from above, i n a l l cases the branches tend to become f a s t i g a t e . Stem cross section revealing an incomplete, outer row of t h i n walled, i n f l a t e d c o r t i c a l c e l l s , beneath which l i e s 2 to 3 rows of small, brownish, incrassate c o r t i c a l c e l l s , which i n turn enclose a broad med-u l l a r y zone of large, thin-walled and hyaline c e l l s ; c e n t r a l strand well developed, becoming dis c o l o r e d with age, i n older stems the i n f l a t e d outer c o r t i c a l c e l l s are collapsed and evident only through the thickened, concave inner walls. Rhizoids few, dark brown, a r i s i n g from the base of v e n t r a l stem leaves, smooth walled. 284 Leaves variable, closely spaced to distant; attitude of the leaves upon the stem d i f f e r i n g l i t t l e from the wet to dry condition,usually loosely appressed imbricate to loosely spreading; shape variable, ovate-lanceolate, oblong-lanceolate, e l l i p t i c or broadly e l l i p t i c ; (0.9) 1.1-1.6 (-2.1) mm long x CO.6) 0.75 - 1.0 (1.1) mm wide; straight to f a l c a t e ; shallowly to deeply concave, rare l y almost plane, p l i c a t e or not plicate,-apex highly variable, almost plane, shallowly concave and gradually tapering to an acute or apiculate point or deeply concave-cucullate with an o f t recurved apiculus, sometimes so deeply concave that the apiculus i s directed toward the adaxial leaf base; margins plane, entire except for a s l i g h t l y crenulate apiculus, sometimes s l i g h t l y i n r o l l e d near the apex, margin i n falcate leaves sometimes i n r o l l e d making the leaf tubulose i n the upper hal f ; costa very stout, single, percurrent i n the apiculus or ending shortly below the apex, rarel y forked, never short and double. Aerolation variable; median leaf c e l l s fusiform to long l i n e a r flexuose; (33) 40-50 (65) urn.long x 5-6 (8) um wide; c e l l s becoming shorter toward the apex, usually rhomboid, sometimes oval; basal c e l l s becoming shorter and wider, somewhat incrassate, becoming yellow with age, p i t s few to many; alar c e l l s numerous, quadrate to short rectangular, usually thin-walled and hyaline, forming a well defined group, rare l y becoming brownish with age. Plants dioicous; male and female plants s i m i l a r , perigonia and perichaetia poorly known; Perigonial leaves variable; outer periogonial leaves rounded obtuse, to 0.4 mm. long, ecostate; inner perigonial leaves ovate-lanceolate, occasionally abruptly acuminate, f i n e l y ser-rulate at the t i p , convave imbricate, ecostate or with a f a i n t single 285 costa reaching s l i g h t l y over h the l e a f length. Outer and middle p e r i -c h a e t i a l leaves broadly ovate, tapering to ah obtuse t i p , ecostate; inner p e r i c h a e t i a l leaves long lanceolate, to 3.0 mm. long, gradually tapering to an acuminate apex, apex becoming frayed with age, 2 to 4 deep p l i c a e ; costa s i n g l e , strong,e ending sh o r t l y below the apex. Sporophyte incompletely known; seta 10 to 12 mm, long, smooth, gradually tapering into the 1.0 to 1.6 mm. long capsule; capsules not c o n s t r i c t e d below the mouth; peristome unknown; spores 15 to 29 um., f i n e l y p a p i l l o s e , l i g h t yellowish green. Hygrohypnum polare may be distinguished by the stout, percurrent costa i n a s s o c i a t i o n with the outermost, incomplete row of i n f l a t e d , t h i n -walled c o r t i c a l "stem c e l l s (Fig. 6!Lh) . No other species of Hygrohypnum e x h i b i t s t h i s character combination. Though easy to recognize, Hygrohypnum polare v a r i e s i n the expres-sion of l e a f shape, l e a f symmetry, l e a f concavity, the nature of the l e a f apex and internode length. Leaf shape v a r i e s from ovate-lanceolate (Fig. 60a) , to oblong-lanceolate (Fig. 60d)i or e l l i p t i c (Fig. 60j) and broadly e l l i p t i c (Fig. 60b). Rarely, small leaves may be ovate. Leaf symmetry va r i e s from s t r a i g h t to strongly f a l c a t e (Fig. 60g). F a l c a t i o n has r a r e l y been seen in; leaves of shapes; other than ovate^lanceolate!'., As i n Hygrohypnum  luridum, f a l c a t e leaves have no taxonomic value, f o r s t r a i g h t and f a l -cate leaves do occur i n a l t e r n a t i n g groups on the same stem. The l e a f apex r e g u l a r l y terminates i n a small, obtuse, sometimes crenulate apiculus. The degree to which the l e a f apex tapers and the amount of concavity exhibited by the l e a f v a r i e s widely. Ovate lanceo-l a t e leaves u s u a l l y taper gradually to an acute apex with the apiculus at the extreme t i p (Figs. 60a & c ) . These leaves vary from almost plane 286 to deeply concave, such that the apex appears l i k e the bow of a boat. In oblongr-lanc-eolate to e l l i p t i c a l leaves the concavity i s frequently so severe that the apex i s rounded cucullateand the apiculus i s directed j toward the adaxial leaf base (Fig. 57j & Fig. 6-1'b) . Leaf attitude varies l i t t l e between the wet and dry conditions. Falcate leaves excepted, leaves are usually loosely imbricated to s l i g h t l y spreading. Imbricated leaves which are also deeply concave are, i n e f f e c t , julaceous (Fig. 60 h) .' Internode length varies within ind i v i d u a l stems and between d i f f e r -ent stems. As a consequence leaves may be crowded to widely spaced. Lindberg (1867) described Hygrohypnum polare var. pseudostramineum. This taxon was characterized by elongated, sparcely branched stems and distant leaves whose apices are weakly secund. The holotype (H-SOL) collected by Malmberg has sidely spaced, broadly e l l i p t i c , cucullate leaves and a vague resemblance to Calliergon stramineum. The variety i s rejected for many specimens of the species are as sparcely branched and have as crowded or as distant leaves as the supposed variety. Further, with crowded, distant, falcate and straight leaves can be seen i n the type specimen of the variety. Hygrohypnum luridum var. e h l e i (Arn.) Wijk et Marg. was o r i g i n a l l y described as Amblystegium e h l e i . This study has shown that the A r n e l l taxon i s a peculiar variant of Hygrohypnum polare. The alleged variety cannot be a l l i e d with H. luridum for the stem cross section reveals an incomplete hyalodermis of i n f l a t e d , t h i n walled c e l l s . Such stem c e l l s occur only i n 13. polare and H. ochraceum. Hygrohypnum ochraceum cannot be considered for as A r n e l l (1913) correctly noted the leaves of his tax-on possessed a=:strong single costa which ended i n the leaf apex, a 287 character not present i n H, ochraceum. A r n e l l (1913) a l s o noted t h a t the stem leaves of h i s v a r i e t y were "haud secunda", while the branch leaves were " a p i c a l i a curvata-falcata". Present observations show that the leaves are more lanceolate and more severely f a l c a t e - c i r c i n a t e than the species as a whole. As i n other species, s t r a i g h t and f a l c a t e leaves do occur on the same stems. The s t r a i g h t stem leaves noted by A r n e l l d i f f e r from the leaves of t y p i c a l K. polare only i n t h e i r l e s s apparent concavity, but the apex i s as crenulate as i n the species i t s e l f . The a l a r c e l l s of both stem and branch leaves are s l i g h t l y l e s s d i s t i n c t than i n the species as a whole. I t i s i n t e r e s t i n g to note that a l l the s p e c i -mens that could be interpreted as the so c a l l e d v a r i e t y come from the Lena River drainage i n S i b e r i a . None i s as yet known from the Jenesei or Ob r i v e r areas or from comparable areas i n Scandinavia or North America. Further,- the s e v e r e l y - f a l c a t e leaves of-these.plants.bear an•interesting resemblance to some species of Drapanocladus. The t y p i f i c a t i o n of the v a r i e t y i s ambiguous. A r n e l l (1913) c i t e d two l o c a l i t i e s as the sources of the specimens on which he based h i s taxon. The l o c a l i t i e s are: S i b e r i a , i n v a l l e flum. Lena, Kumachsur, 70° 30' l a t . sept., N i l s s o n -Ehle 1898 and S i b e r i a , i n v a l l e flum. Lena, Bulun, 70° 43' l a t . sept., Nilsson-Ehle 1898. At S-PA there are 4 specimens agreeing with the data f o r the Kumachsur l o c a t i o n and one at H-BR. The lone specimen from H-BR and 3 of the 4 S-PA specimens bear the c o l l e c t i n g date of 19 July 1898, whereas the remaining S-PA specimen i s dated 26 July 1898. A s i n g l e specimen from the Bulun c i t e dated 19 Sept. 1898 i s at S-PA. None of the Kumachsur specimens appear to be c l e a r duplicate of one another yet they are unquestionably the same v a r i a t i o n of II. polare. A si n g l e specimen from Kumachsur at S-PA has been appropriately designated as the lectotype. 288 In l i t e r a t u r e not a v a i l a b l e f o r t h i s study, Bryhn (1902) described Hygrohypnum polare var. falcatum. At HnBR there i s a specimen bearing t h i s name that was c o l l e c t e d by G. Simmons i n 1898 from Faulkefjord i n N. V. Gronland and i d e n t i f i e d by N. Bryhn. Other specimens bearing t h i s v a r i e t a l e p i t h e t have been located, but none have borne a Bryhn determina-t i o n nor have any but the above mentioned specimen and another Simmons c o l l e c t i o n from Ellesmere Is. borne c o l l e c t i n g dates p r i o r to 1902. I t seems reasonable to assume that the specimen from N. V. Gronland i s the one on which Bryhn based h i s v a r i e t y . Upon t h i s assumption the v a r i e t y i s judged to be a f a l c a t e leaved v a r i a n t of H_. polare and not worthy of taxonomic rank. Numerous workers (Lindberg, 1867; Schimper, 1876; Limpricht, 1904; Roth, 1905; Brotherus, 1923; Moenkemeyer, 1927; Grout, 1931 and Martens-son, 1956) have remarked that the sporophyte of H. polare was v i r t u a l l y unknown. De t a i l s of the capsule and peristome are unknown, however, i t seems to have been overlooked that Limpricht (1904) noted that E. Nyman c o l l e c t e d f e r t i l e material i n Sweden's Lule Lappmark d i s t r i c t on 27 July 1891. As Limpricht noted the sporophytes are old and p a r t i a l l y decayed. However, i t i s more important to know that the species i s not completely s t e r i l e . I t i s hoped that Scandinavian workers w i l l endeavor to locate f e r t i l e m a terial. A measure of the elusiveness of these structures can be measured by t h e i r apparent absence from the adjacent and i n t e n s i v e l y studied Tornetrask. The questionable occurence of Hygrohypnum polare i n continental Europe and North America and i t s confusion with strong, single costate forms of H. luridum i s w e l l known i n the l i t e r a t u r e (Boulay, 1872; Ren-auld, 1883, Husnot, 1894; Amman, 1912 and P a r r i a t , 1952). Husnot's 2 8 9 troublesome e x s i c c a t i Musci G a l l i a e #592 has played a c e n t r a l r o l e i n the problem. Collected i n the Pyrennes from the o u t l e t of Lac Vert near Luchon, the exsiccata was d i s t r i b u t e d as Hypnum palustre var. laxum. The only specimen of t h i s exsiccata a v a i l a b l e f o r study i s at S-PA. The specimen i s unquestionably Hygrohypnum polare. However, c e r t a i n stems bear leaves that are r e a d i l y mistaken f o r H_. luridum, f o r they are not cucull-ate i n the apex and the costa tapers to a slender p o i n t that ends we l l below the apex. The various names and comments that have been applied to t h i s exsiccata by Boulay, Husnot, Amann and P a r r i a t are e a s i l y a t t r i b u t a b l e to the t y p i c a l and abberant leaves on the specimen. Growth i n t h i s southern most s t a t i o n of an otherwise northern species no doubt accounts f o r the somewhat abberant form. The presence of Hygrohypnum  polare i n continental Europe i s c l e a r l y established by Lisowski 1s Bryotheca Polonica numbers 298, 670, 671 and 818 from the Tatras. S i m i l a r l y , H. polare i s widely scattered i n a r c t i c North America and recent report (Brassard, 1975) places the species i n c e n t r a l Labrador. The only species of Hygrohypnum with which H. polare may be confused i s H. luridum. The confusion i s confined only to those strong, s i n g l e costate forms of H. luridum. The most important d i f f e r e n c e resides i n the presence of the i n f l a t e d c o r t i c a l stem c e l l s of E. polare. Lindberg (1867) c i t e d two specimens c o l l e c t e d on Spitzbergen by Malmgren i n 1861 as the basis for Hypnum polare, the basionym f o r Hygro- hypnum polare. One specimen was c i t e d from "Kobbe Bay 6", and another from "Wahlenbergs bay i n t e r Bryum ventricosum". Lindberg d i d not spec i f y a holotype and inconsistent c i t a t i o n on specimen l a b e l s has further complicated t y p i f i c a t i o n . Three c o l l e c t i o n s , two of which e x i s t as p a i r s of duplicates, f o r a t o t a l of f i v e specimens at e i t h e r S-PA or 290 H-SOL, can be a t t r i b u t e d to Malmgren, One c o l l e c t i o n , duplicated at S-PA and H n S O L , bears handwritten l a b e l s w r i t t e n by the same hand and bear the name "Robbe bay".. " The name i s quite contrary to the name i n Lindberg's d e s c r i p t i o n of Hypnum polare. The specimen has f a l c a t e leaves. The only known specimen from Wahlenbergs bay i s at S-PA. The specimen bears a p r i n t e d l a b e l bearing Malmgren's name, the date 1861 and Insulae Spitzbergensis, Written by a hand d i f f e r e n t from that on the "Robbe bay" specimen i s the phrase "Wahlenbergs bay". Though Bryum ventricosum i s present i n the packet, i t s presence there i s not noted on the packet as in d i c a t e d i n Lindberg"s d e s c r i p t i o n . The specimen i s a good representative of Hygrohypnum polare with- s t r a i g h t leaves. A t h i r d Malmgren c o l l e c t i o n from Spitzbergen and dated 1861 i s dup-l i c a t e d at S'fPA and H-SOL. These duplicates bear l a b e l s written i n the same hand as occurs on the "Robbe bay". Of s i g n i f i c a n c e i s the s t a t e -ment on each packet; "Augusta bay i n t e r Bryum ventricosum". The phrase " i n t e r Bryum ventricosum" corresponds to Lindberg's reference to the Wah-lenbergs bay specimen, whose act u a l l a b e l does not carry the remark. Remarkably, the Augusta bay specimen contains no Bryum of any s o r t . Morphologically, the Wahlenbergs bay and Augusta bay specimens are s i m i l a r . Although both s t r a i g h t and f a l c a t e leaves occur i n Hygrohypnum  polare, most specimens have s t r a i g h t leaves. The Wahlenbergs bay c o l l e c -t i o n at S-PA with i t s s t r a i g h t leaves best represents the most frequent form i n the species and i s thus chosen as the lectotype f or H_. polare. 291 Fig. 60a - k. Variation i n the leaf shape and the habit of the shoots of Hygrohypnum polare. a - g, j - k. V a r i t a t i o n i n leaf shape. h - i . V ariation i n the habit of the shoots. Scale: a - g, j - k; I 1mm | h - i ; . The shoot i s approximately 1 cm long 292 293 Fig. 61 a - h. C e l l u l a r d e t a i l s of the foliage leaves and the stem of Hygrohypnum polare. a,,b. Leaf apices, c, d. Median leaf c e l l s . e. Marginal leaf c e l l s f, g. Alar c e l l s . h. Stem cross section. Scale: a , f - h; I ' 100um I b - e; I 100um l : 295 Fig . 62. Hygrohypnum polare 296 E x s i c c a t i Examined Bauer, Musci Europaei e x s i c c a t i #648 as Hygrohypnum polare (BRNM, UCA, H) Husnot, Musci G a l l i a e #592 as Hypnum palustre var, laxum. (S-PA) Lisowski, Bryotheca Polonica Fasc. X, #298, CS<-PA„ H, CANM,BP, LE) Fasc.XXV, #670. (S-PA; H, CANM,BP,LE) Fasc. XXXI, #818. (S-PA, H, CANM,BP, LE) Fasc. XXV, #671 as Hygrohypnum polare var. f a l c a t a (CANM, BP,LE) Selected Specimens Examined Canada B r i t i s h Columbia Lake Lindeman; Williams 17 May 1898 as Hypnum polare. (NY) Labrador C h u r c h i l l F a l l s , Bridge Camp area; Brassard 5178. (NFLD) Yukon T e r r i t o r y Southern O g i l v i e Mtns., One Eighty Lake; Horton 2816 Northwesl^Territories Ellesmere Island B e i t s t a d f j o r d ; Simmons 10 June 1899 as Hypnum polare, (H-BR) Bedford Pen. Is., Cape Sabine; Simmons 17 Aug. 1898 as Hypnum polare. (H-BR) Cape Rutherford; Simmons 21 Aug. 1893 as Hypnum polare. (H-BR) Craig Harbour; D u t i l l y 1232 as Hygrohypnum polare. (MICH; NY) Head of Tanquary Fjord; Brassard 1536. (UAC, NY, MICH) B a f f i n Island Cape Searle; Steere 33. (USA) Head of Clyde Inl e t ; Wynne-Edwards 9264. (NY) ""1 " S l i d r e F j o r d ; Troeslen 14 July 1952 (DUKE) United States Alaska Mt. McKinley National Park, Deep Canyon; Murie 8 July 1951. (NY) Brooks Range, Fr a n k l i n Mountains, Schrader Lake-Peters Lake area j u s t N. of Mt. Chamberlain; Steere 18926. (NY) Greenland N. V. Gronland, Faulkefjord; Simmons Aug. 1899. (H-BR) Hurry Inl e t ; Dusen 7 Aug. 1899 as Amblystegium polare. (H-BR,NY) Godhavn; Holmen 14400. (S-PA,NY) Svartenhuk Peninsula, Simiutap kua; Holmen 17103. (NY, S-PA) Martlek; Berggren 1870 as Hypnum polare. (S-PA) Head of f j o r d south of Marmorlik; Holmen 16087. (S-PA) Thule; F r i s t r i p Sept. 1954. (NY,S-PA) Noth^st Land, T-S0; Hodmen 19181. (S-PA,NY) 297 Arsuk; Lagulaury, (SnPA) Disco Land, Hammersdal; P o r s i l d 340, CSi-PA) Peary Land, S , coast of Independence Fjord; Holmen 7158, CS-PA) Scoresby sund, Charcots Land; Holmen 18891. (S-PA,NY) Spitzbergen Kobbe Bay; Malmberg 1861 as Hypnum polare. (H-SOL) , Augusta Bay Malmberg 1861 as Hypnum polare. (H-SOL) Wahlenbergs Bay; Malmberg 1861 as Hypnum polare. (S-PA, LECTOTYPE) Murchison Bay, Celsa bug; Wulff 28 Aug. 1899 as Amblystegium polare. (S-PA,NY) Kap Foster, Baslandet; Wulff 20 July 1899 as Amblystegium polare. (S-PA) Kung Karl's Land, Johnsensberg; Anderson & Hesselman 17 Aug. 1898 as Amblystegium polare. (S-PA) Prince Charles Foreland; Beggren 1868 as Hypnum polare. (NY) Norway N. Cpdal, i n Drivan; Lindberg 1 Aug. 1882 as Amblystegium  polare. (H-SOL) Sweden Lule Lappmark, Jokkmokk; Nyman Aug. 1893 as Amblystegium  polare. (S-PA) Torne Lappmark, Karesuando; Martensson 27 July 1949. (NY,S-PA) Torne Lappmark, Abiskojokk; Jaederholm 15 July 1917 as Limnobium polare. (S-PA) Finland Lapponia ov., Dolgaga guba prope Svjaetoi; Brotherus July 1872. (NY) Poland Montes T a t r i A l t i i n v a l l e Kociot Mieguszowiecki, Lisowski 28 Aug. 1956 as Bryotheca. polonica #29.8 as Hygrohypnum  polare France Haute Garrone, Lac Vat pres Luchon; Husnot, i n Musci Galliae 592 as Hypnum palustre var. laxum. (S-PA) Soviet' Union S i b e r i a , Jenesei, Plachino; A r n e l l 23 July 1876 as Amblystegium polare. (H-SOL) S i b e r i a , Jenesei, T o l s t o i ; A r n e l l 1 Sept. 1867 as Amblystegium polare. (H-SOL) S i b e r i a , Ural Mountains, Tobolsk; Sukatschew 30 June 1909. (H) S i b e r i a , Vostoczhye Sajany, the upper part of the Uda R.; Bardunov 11 Aug. 1961. (S-PA) Novaya Zemlya, Matoschkin Schar; Ekstram 1905. (S-PA) Novaya Zemlya, Karmakul Bay; Ekstram Aug. 1895 as Amblystegium polare. ('S-PA?-" NY)-; as Hypnum polare Rossia A r c t i c a , Terra Franz Josef, i n s u l a Aagaard; Savicz 657, (S-PA) Rossia a r c t i c a , Insulae Vise; Savicz 1500. (S-PA) 298 Asia, a r c t i c a , Kap Tschelpuschin; Kjellman 19>-20 Aug. 1878 as Amblystegium polare. CS^PA) Kola Peninsula, Lap. murmania, f l u s Harfofka; Brotherus July 1877 as Amblystegium polare. (H-SOL) Great B r i t a i n Scotland West Ross, north side of Beinn Dearg; Wallace 1 August 1952. ( c i t e d from Wallace 1972) 299 Hygrohypnum ochraceum (Turn, ex Wils.1 Loesk,, Moosfl. Harz, 321. 1903. Synonymy Hypnum ochraceum Turn, ex Wils,, B r y o l . B r i t , 400. 58. 1855. Hypnum simpliciusculum Mohr ex Wils., Bryol. B r i t . 400. 1855. nom. nud, i n syn. Limnobium ochraeeum (Wils.) Schimp., Bryol. Eur. 6:75. 575. 1855. Hypnum ochraceum var. complanatum Milde, B r y o l . S i l e s . 376. 1869. Hypnum ochraceum var. flaccidum Milde, Bryol. S i l e s . 376. 1869 Hypnum ochraceum var. uncinatum Milde, Bryol. S i l e s . 376. 1869 Amblystegium ochraceum (Turn, ex Wils.) Lindb., Musci Scand. 33. 1879. Amblystegium simplicinerve Lindb., A. Soc. F. F l f Fennica 3(1): 99. 1886. Ca l l i e r g o n ochraceum (Wils.) Kindb., Eur. N. Am. Bryin. 1:82. 1897. Amblystegium ochraceum var. flaccidum (Mild.) Braithw., B r i t . Moss. F l . 3:59. 1898. Hypnum ochraceum var. ovaturn Kaal., Nyt. Mag. Naturvid. 40:263. 1902. Hygrohypnum ochraceum var. complanatum (Mild.) Loesk., Moosfl. Harz'. 321. 1903, Hygrohypnum ochraceum var. uncinatum (Mild.) Loesk., Mossfl. Harz. 321. 1903. Hypnum simplicinerve (Lindb.) Limpr,, Laub, Deutsch. 3:545. 1904. 300 Limnobium ochraceum var. complanatum (Mild.) Roth, Eur. Laubm. 2:650. 1905. Limnobium ochraceum var. filiforme (Limpr.) Roth, Euro. Laubm. 2:651. 1905. Limnobium ochraceum var. flaccidum (Mildl) Roth, Eur. Laubm. 2:650. 1905. Limnobium simplicinerve (Lindb.) Roth, Eur, Laubm. 2:651. 39f.6. 1905. Limnobium ochraceum var. uncinatum (Mild.) Roth, Eur. Laubm. 2:650. 1905. Limnobium ochraceum var. nivale Zett. in Roth, Eur. Laubm. 2:651. 1905. Limnobium ochraceum var. falcatum Mild, ex Roth, Hedwigia 46:206. 1907, Hygrohypnum simplicinerve (Lindb.) Broth., Nat. P f l . 1(3): 1041. 1909. Drepanocaldus furcatus Roth et Bock, Hedwigia 48:176. 6f.7. 1909. Limnobium ochraceum var. theresianum Roth, Hedwigia 48:214. 1909. Breidleria ochracea (Web.) Loesk., Studien 172. 1910. Stereodon crassicostatus Kindb, , Rev,, Bryol, 37": 14. 1910. (Type at S-PA) Hygrohypnum ochraceum var. filescens Loesk. in Bauer, Musci Eur. Exs. ser 13n. #645. 1910. Hygrohypnum ochraceum var. obtusifolium Spindl. Hedwigia 50:182. 6. 1911. 301 Hygrohypnum ochraceum var. simplicinerve (Lindb.) Spindl. 50:3.84. 6. 1911. Ca l l i e r g o n perdecurrens Okam., Bot. Mag. Tokyo 25:140. 1911. Hygrohypnum dilatatum f o . t r i s t e Podp., Vysledky VI. 47. 1912. Hygrohypnum ochraceum var. f i i i f o r m e (Limpr.) Amann. F l . Mousse. Suisse 2:361. 1912. Hygrohypnum orchaceum var. flaccidum (Mild.) Amann, F l . Mouss. Suisse. 2:361. 1912. Hygrohypnum ochraceum f o . t r i s t e (Podp.) Podp., Cas. Moravsk. Mus. Zemsk. Brno. 13:225. 1913. Hygrohypnum ochraceum fo. complanatum (Mild.) Moenk., Susswasserf1. 154. 1914. Hygrohypnum ochraceum fo. f i l i f o r m e (Limpr.) Moenk., Suss-wasserfl. 154. 1914. Hygrohypnum ochraceum fo. obtusifolium (Spindl.) Moenk., Susswasserf1. 154. 1914. Hygrohypnum ochraceum f o . uncinatum (Mild.) Moenk., Suss-wasserf 1. , 154. 1914. Hypnum pseudolycopodoides Kindb. ex Nichols, B r y o l o g i s t 19:40. 1916. (Type at S-PA) Hygrohypnum ochraceum var. trieste.(Podp.) Podp., Skom.. Kuub. P r i r , Brno, 5:21. 1923. Hygrohypnum ochraceum fo. simplicinerve (Lindb.) Moenk., Laubm. Eur. 740. 1927. Hypnum crassicostatum (Kindb.) Grout, Bryo l o g i s t . 33:71. 1935. nom. i n v a l i d , i n synon. Hygrohypnum ochraceum f o . ovatum (Kaal.) C. Jens., Skand. Bladmfl. 464. 1939. 302 Hygrohypnum ochraceum f o . f i l e s c e n s (Loesk. i n Bauer) Podp., Consp. 575. 1954. Hygrohypnum ochraceum f o . theresianum (Roth) Podp., Consp. 575. 1954. Nomen nuda Hygrohypnum ochraceum f o . brevifolium (C. Jens, i n Grout) Podp., Consp. 575. 1954. Hypnum ochraceum var. brevifolium C. Jens, i n Grout, Bot. Tidskk. 20:113. 1896. Hygrohypnum ochraceum var. brevifolium Arn. et. C. Jens, i n Moenk., Laubm. Eur. 740. 1927. Names of nomen nuda f o r which the l i t e r a t u r e has been unavailable f o r v e r i f i c a t i o n . Hygrohypnum- ochraceum var. tenue Boul. i n Grev., Rev. Bryol. 10:39. 1883. Hygrohypnum ochraceum var. tenuis Meyran, Ann. Soc. Bot. Lyon 39:141. 1915. Names of taxa ,.,of which the l i t e r a t u r e has been unavailable-- f o r assess-ment. Amblystegium ochraceum var. complanatum (Mild.) Moell., Bot. Not. 190-7. 144. 1907. Amblystegium ochraceum var. complanatum Moell., Fort. sk. vaxt 2 Moss 41. 1907. Amblystegium ochraceum var. f i l i f o r m e (Limpr.) Moell., Bot. Not. 1907. 144, 1907. Amblystegium ochraceum var. flaccidum Moell., Fort, sk vast 2 Moss. 41. 1907. Amblystegium ochraceum var. ovatum (Kaal.) Moell., Bot. Not. 1907, 144. 1907. 303 C a l l i e r g o n perdecurrens Broth, ex. Okam., Bot. Mag. Tokyo 25:140. 1911. ^ Hygrohypnum dilatatum fo. t r i e s t e (Podp.) Podp., Vysledky VI. 47. 1912. Hygrohypnum ochraceum var. ovatum K a i l , ex Moell., Bot. Not. 1907. 144. 1907. Hygrohypnum ochraceum f o . t r i e s t e (Podp.) Podp., Cas. Moravsk. Mus. Brno 13:225. 1913. Hygrohypnum ochraceum var. t r i e s t e (Podp.) Podp., Skom. Klub. P r i r . Brno 5:21. 1923. Hygnumcdchraceum var. f i l i f o r m e Limpr., Krypt. F l . Schles 1:63. 1876. Hypnum ochraceum var. ovatum Kaal., Nyt. Mag. Naturvid. 40:263. 1902, Plants v a r i a b l e ; s o f t or coarse, forming small t u f t s or extensive 2 mats or swollen t u f f s as much as 10 to 15 cm , t i g h t l y woven or loosely entangled and e a s i l y fragmenting; color b r i g h t shiny yellow green, d u l l yellow-green, b r i g h t or dull-green, d u l l olivaceous-green with or without ru s t y mottling, d i r t y brown, r a r e l y b l a c k i s h or blackish-green. Stems 2-15 (20) cm long, v a r i o u s l y prostrate and creeping or ascending near the apex; stem t i p s s t r a i g h t or hooked; stems generally f o l i o s e throughout, leaves i n older extremities of long stems frequently shredded or absent. Branching i r r e g u l a r , u sually widely spaced, i n short stems branches are sometimes crowded, long stems are sometimes almost completely unbranched, on other occasions long stems are almost pinnately branched. Stem cross sections revealing 2 to 3 rows of small, thick-walled, yellowish to reddish-brown c o r t i c a l c e l l s , enclosed by a s i n g l e outer row of hyaline, 304 t h i n walled and often i n f l a t e d epidermal c e l l s ; medullary c e l l s larger, hyaline and think walled, sometimes becoming thicker walled and discolored with age; central strand w e l l developed. Rhizoids of variable occurrence, apparently humidity dependent, reddish-brown, a r i s i n g from the base of ventral stem leaves. Leaves variable among d i f f e r e n t plants or within i n d i v i d u a l stems or branches, usually ovate lanceolate or lanceolate, infrequently ovate, rarel y broadly ovate; (0.7) 1.0 - 1.8 (2.5). mm long x (0.2) 0.5 - 0.8 (1.2) mm wide; attitude upon the stem variable, crowded or distant, loosely imbricate to spreading, straight or f a l c a t e , falcate leaves may have one margin infolded along one side as a wing, or the leaf may be sharply folded along the midline i n the upper half of the leaf whereupon the folded portion i s then sharply turned to one side or the other, at other times falcate leaves may be concave caniculate, especially i n the upper h a l f , straight leaves are shallowly concave to plane; upon drying leaves may become somewhat crisped or not at a l l , i n those leaves that are folded through the midline i n the upper half the folded portion tends to c u r l through several turns upon drying, i n leaves that attain'larger--dimensions there, i s a tendency for them to undergo shrinkage upon drying, which i s accompanied by a tendency to wrinkle and a suggestion of p l i c a t i o n ; leaf margins entire, except where minutely denticulate or serrulate i n the apex; apex acute to long tapering accuminate, obtuse or bluntish; leaves concave to plane; sometimes appearing decurrent by virtue of the persistent c o r t i c a l stem c e l l s ; costa variable, almost absent, short and double, usually long and double with one or both arms reaching midleaf or beyond, or single to midleaf or beyond or single with 1 to 3 l a t e r a l forks, generally coarse throughout. Aerolation variable; median' leaf c e l l s fusiform to long lin e a r 305 flexuose;(30) 37-83 (120) um long x (4) 5-6 (8) um wide; c e l l s generally shorter toward the apex; marginal leaf c e l l s becoming shorter toward the apex; toward the base becoming longer or shorter and wider, throughout the middle of the leaf the marginal leaf c e l l s may become shorter, but l i t t l e wider or longer and narrower than the adjacent median leaf c e l l s ; c e l l s toward the leaf base variable generally becoming wider, but variously becoming longer, shorter or changing l i t t l e i n length; basal c e l l s incrassate, p i t s few to none; alar c e l l s variable, quadrate, rectangular, sometimes l i n e a r , t h i n walled or incrassate, hyaline, almost never discolored, forming an i r r e g u l a r l y defined group of c e l l s which occur as 2 to 3 rows of c e l l s which l i e along the margin, the row of c e l l s on the margin grades from quadrate at the point of insertion to rectangular to li n e a r at a distance of 4 or 5 c e l l s above the point of in s e r t i o n , the second and t h i r d rows of c e l l s are more vairable and often tend to grade into the adjacent c e l l s . Plants dioicous; male and female plants similar though the males are more slender; perigonia ovoid; outer perigonial leaves scale l i k e , ecostate, entire; middle and inner perigonial leaves ovate with an abruptly acuminate apex, to 0.9 mm long, e n t i r e , ecostate, concave-imbricate, squarrose recurved i n the upper half; outer and middle p e r i c h a e t i a l leaves ovate and gradually to abruptly acuminate i n the apex, squarrose i n the upper h a l f , concave below, margins entire except minutely serrulate i n the apex, costa variable, short and double, absent; inner p e r i c h a e t i a l leaves long tapering lanceolate, to 3.5 mm long, erect, entire except sometimes minutely serrulate i n the apex, p l i c a t e , costa variable, single, long and double or absent. Seta 16 to 31 mm long reddish-brown, smooth, erect or s l i g h t l y arched; 306 capsule t y p i c a l f o r the genus; annulus present, of 2 to 3 rows of c e l l s , deciduous. Preistome t y p i c a l f o r the genus; endostome with 1 to 3 c i l i a between adjacent segments; spores, Hygrohypnum ochraceum i s a polymorphic, yet very d i s t i n c t i v e species, which may be distinguished from other species i n the genus by the d i o -icous sexuality, the outer layer of i n f l a t e d c o r t i c a l stem c e l l s (Fig. 66a) the v a r i a b l e costa (Fig. 64 a-1) and the nature of the a l a r c e l l s (Fig. 66 b-e) . The study of herbarium specimens and l i v i n g cultures have shown that Hygrohypnum ochraceum va r i e s i n l e a f shape and s i z e , the nature of the l e a f apex, c o s t a l structure, the marginal l e a f c e l l s , l e a f symmetry, internode length and habit. The l e a f shape us u a l l y v a r i e s from ovate-lanceolate (Fig. 64a) to lanceolate (Fig. 64k). Ovate leaves (Fig. 6,4j) frequently occur and do so broadly ovate leaves (Fig. 64i), but the l a t t e r are rare. The l e a f apex i s acute. However, the t i p may be sharp (Fig. 65) or blunt (Fig. '65c). The margin of the l e a f apex adds further d i v e r s i t y to the l e a f by varying from e n t i r e to minutely denticulate to serrulate (Figs. 65a and c ) . A l l of these v a r i a t i o n s may occur among the leaves on a sin g l e stem. Through d i f f e r i n g i n d e t a i l , the costa of Hygrohypnum ochraceum i s as v a r i a b l e as that of _H. luridum. The costa i s usually double with one or both arms reaching midleaf or s l i g h t l y beyond. However, i t may also be short and double, short and s i n g l e , s i n g l e to midleaf or beyond, sin g l e with 1 to 3 l a t e r a l forks or sometimes almost absent. A l l of these v a r i a t i o n s may occur frequently among the leaves of a s i n g l e stem. 307 The marginal leaf c e l l s occurring through the middle of the leaf exhibit a remarkable v a r i a t i o n . They may be longer, shorter or l i t t l e d i f f e r e n t from the adjacent median leaf c e l l s . In some cases the long marginal leaf c e l l s are reminiscent1 of Hygrohypnum b e s t i i (Fig. 64d)• The alar region i s generally di f f e r e n t i a t e d as a group of quadrate to l i n e a r c e l l s forming 2 to 3 rows of c e l l s extending along the margin of the leaf for a distance of 4 to 6 cell^lengths above the point of leaf o insertion (Fig, 66 b-e). The marginal row of alar c e l l s c h a r a c t e r i s t i c a l l y varies acropetally from quadrate through short rectangular to rectangular or even l i n e a r (Figs. 66 b-d). The inner rows of di f f e r e n t i a t e d alar c e l l s are less regular i n their form. In some cases the basal c e l l s become enlarged and thin walled. In such cases the basal c e l l s and ala r c e l l s merge with l i t t l e d i f f e r e n t i a t i o n between them, save for the row of marginal c e l l s (Fig. 66e). Leaf symmetry and s i z e , internode length, and o v e r a l l appearance have played important roles i n the recognition of apparent subspecific taxa. Each of these characters i s variable and each may influence the other. The leaves of Hygrohypnum ochraceum vary from straight to falcate ^uncinate. As i n the case of E. luridum and H_. polare, the v a r i a t i o n between straight and curved leaves may occur between d i f f e r e n t plants or within i n d i v i d u a l plants. Within ind i v i d u a l plants stem segments bearing straight leaves have been observed giving way to falcate or c i r c i n a t e leaves or vice versa (Fig. 63 c) . In other cases stems have been observed bearing straight leaves, while branches bore falcate leaves. The falcate nature of the leaves of Hygrohypnum ochraceum varies. In some specimens with small leaves the leaves are concave-caniculate and the f a l c a t i o n i s evident throughout the leaf (Fig. 63' b S d). Such 308 leaves are firm and r e t a i n t h e i r appearance whether wet or dry. In other cases the lower h a l f of the l e a f i s more or l e s s ovate-concave and s t r a i g h t . The upper h a l f of the l e a f i s i n f o l d e d along i t s midline and then decidely f a l c a t e (Fig. 64g). The f o l d i n g i n the upper h a l f imparts a caniculate appearance to the leaves. Upon drying such leaves may twist through several turns of t h i s folded upper h a l f (Fig. 63e). In other f a l c a t e leaves one side of the l e a f may be infolded as a wing and the l e a f i s then curved away from the side of the f o l d (Fig. 64d). S t r a i g h t leaves vary i n two ways. They may e i t h e r be l o o s e l y imbricate-spreading (Fig. 63c), or they may be somewhat complanate (Fig. 63a)-. Leaves that occur along a gradient of increasing length and width also e x h i b i t an increased f l a c c i d i t y . A measure of t h i s softness i s the conspicuous side to side or l a t e r a l shrinkage that accompanies d e s s i c a t i o n i n larger leaves. The shrinkage r e s u l t s i n c r i s p i n g or wrinkling. In those large f a l c a t e leaves which become folded and twisted i n the upper . h a l f , the twisting becomes e s p e c i a l l y pronounced (Fig. 63e). The internode length v a r i e s from short, such that the leaves are crowded imbricate (Fig. 63c) to long, such that the stem i s c l e a r l y v i s i b l e between adjacent leaves (Fig. 63a). Plants that have been grown i n culture have uniformly responded by increasing the internode length beyond that attained under natural conditions. The r e c r i p r o c a l r e a c t i o n of internode shortening was not observed. Among the plants bearing f a l c a t e leaves l e a f s i z e , internode length and l e a f shrinkage and c r i s p i n g upon drying may looked upon as increasing p a r a l l e l to one another. Among many specimens almost con-tinuous v a r i a t i o n can be observed from small, firm, c l o s e l y spaced 309 f a l c a t e leaves to l a r g e r , f l a c c i d , widely spaced leaves which are markedly shrunken and crisped when dry. Remarkable, specimens from opposite ends of t h i s spectrum that have been studied i n c u l t u r e have responded by producing l e s s f a l c a t e to almost s t r a i g h t , complanate leaves, with long internodes. As number 645 of Bauer's Musci europaei e x s i c c a t i Loeske described Hygrohypnum ochraceum var. f i l e s c e n s as "forma f i l e s c e n s , foliorum apicibus valde brevibus." Limpricht's o r i g i n a l d e s c r i p t i o n of H. ochra- ceum var. f i l i f o r m e (Krypt. F l . Schles. 1:63. 1876) was unavailable f o r examination. However, Limpricht's (1904) r e c h a r a t e r i z a t i o n oi the p l a n t -stated "sehr lang fluthend, fadenformig, mit f a s t drehund beblattern, sehr dunnen, verlangerten Aesten. B l a t t e r kurz zugespitzt " The leaf apex has apready been shown to be a v a r i a b l e character. Very long stems or branches do not n e c e s s a r i l y have to have long internodes. Examination of two specimens of the Bauer exsiccata has shown that the very long stems also have v a r i o u s l y elongated internodes and s t r a i g h t or f a l c a t e leaves. This taxon i s rejected f o r i t i s based on v a r i a b l e features. Each of the c r i t e r i a employed by Milde (1969) to characterise and d i s t i n g u i s h Hypnum ochraceum var. flaccidum and H. ochraceum var. complanatum are based on v a r i a b l e features. The two taxa were seen to share "Stengel lang," and leaves " b r e i t - l a n z e t t l i c h " or " b r e i t - l a n z e t t f o r m i g " and "locker abstehend" or "locker beblattern." Variety flaccidum was described as " b l a t t e r u b e r a l l a l l s e i t i g abstehend, e i n f a r b i g braun, "whose leaves were "lang zugespitzt," whereas var. complantatum was described as " b l a t t e r f a s t zweireihig g e s t e l l t , locker stohend abstehand, nirgends einseitwedig, s a f t i g , grun, e i n f a r b i g , " with leaves "kurzer zugespitzt." Color v a r i e s widely within i n d i v i d u a l plants and throughout the species. A complanate and/or spreading a t t i t u d e on the leaves has been produced i n culture from 310 plants otherwise bearing f a l c a t e leaves. Since the two taxa based on v a r i a b l e characters they are r e j e c t e d . Milde (1869) also described Hypnum ochraceum var. uncinatum on the basis of the "stengel an der s p i t z e hakenformig einwartsgekrummt, B l a t t e r einseitwendig, l a n g l i c h , lanzugespitzt, stumplich, rot h und grun geschecht." Numerous specimens e x h i b i t v a r i a t i o n of t h i s basic form, but as was pointed out e a r l i e r , l e a f f a l c a t i o n i s a highly v a r i a b l e feature and cannot e f f e c t i v e l y be used d e l i m i t a taxon. Lindberg i n Hult (1886) placed much weight upon "nervo semper s i m p l i c i c r a s s i u s c u l o " i n h i s c h a r a c t e r i z a t i o n of Amblystegium simplicinerve. Collected by H j e l t & Hult from the Ounasjoki River near Rovaniemi i n Finland (at H-SOL) the holotype c l e a r l y exhibits as many leaves bearing short and double costae as i t does strong s i n g l e costae. The a t t i t u d e of the leaves also varies from f l a c a t e to s t r a i g h t and imbricate. The p l a n t i s an average example of Hygrohypnum ochraceum. Neither the type d e s c r i p t i o n nor any specimen of Hygrohypnum ochra- ceum fo. ovatum (Kaal.) C. Jens, have been a v a i l a b l e for examination during t h i s study. Jensen's (1939) b r i e f d e s c r i p t i o n c l e a r l y remarks on the ovate nature of the leaves and the short, broad l e a f apex. Both of these features are v a r i a b l e . Should the type of t h i s taxon become a v a i l a b l e i t i s l i k e l y that i t w i l l be shown that i t i s no more than a form of H. ochraceum. Spindler (1911) provided neither a formal d e s c r i p t i o n nor a c l e a r reference to a holotype f o r h i s Hygrohypnum ochraceum var. obtusifolium. However, a t H i s a Spindler specimen present at d u p l i c a t e s , which bear the name H. ochraceum nov. var. obtusifolium. The plants are usually dark and encrusted with s o i l and a l g a l p a r t i c u l e s . The leaves are broad and t h e i r apices • obtuse, but otherwise there i s nothing unusual about the p l a n t s . 311 The type d e s c r i p t i o n of Hygrohypnum dilatatum ver. t r i s t e Podp. has not been a v a i l a b l e for study. However, a lone Podpera c o l l e c t i o n bearing t h i s name dated 1909 from S-PA proved to be a f l a c c i d , f a l c a t e leaved form of Hygrohypnum ochraceum. The only ©ther•species of Hygrohypnum with which II. ochraceum could be confused i s H. luridum. Such confusion can occur only through t h e i r s u p e r f i c i a l s i m i l a r i t y f o r they are fundamentally very d i f f e r e n t . The following chart w i l l point out the important d i f f e r e n c e s . H. ochraceum H. luridum Sexuality Annulus Dioicous Present Autoicous Absent Stem cross section Outer c o r t i c a l layer i n -f l a t e d and t h i n walled. A l l c o r t i c a l c e l l s small, t h i c k walled. Alar c e l l s 2 to 3 v e r t i c a l rows of quadrate to rectangular or l i n e a r c e l l s increasing i n length acropetaly. Of-t h i n walled, seldom d i s -colored, never excavated. Generally many small, quad-rate to short rectangular c e l l s , u s ually incrassate and d i s c o l o r e d , sometimes excavated. Variously acute, acuminate, e n t i r e or denticulate or ser r u l a t e , sometimes obtuse. Always acute and e n t i r e , margins sometimes i n r o l l e d as to d i f f e r e n t i a t e a pseudoapiculus. 312 F i g . 63 a - e. V a r i a t i o n i n the habit of l e a f y shoots of Hygrohypnum ochraceum and comparisons between the wet and dry conditions i n the shoots a. A shoot with widely spaced, complanate leaves. b. The ve n t r a l view of a shoot with strongly f a l c a t e leaves. c. A shoot with f a l c a t e and s t r a i g h t , narrowly lanceolate leaves. d. e. A shoot with strongly f a l c a t e leaves as seen i n the moist (d) and dry (e) conditions. Scale: These shoots are approximately 1.2 cm long 314 Fig. 64 a - 1. Variation i n the leaf shape of Hygrohypnum ochraceum. Scale: I 1mm 315 316 Fig . 65 a - i . C e l l u l a r d e t a i l of the foliage leaves of Hygrohypnum  ochraceum. a - c, f. Leaf apices. d, e. Marginal leaf c e l l s . g . - i . Median leaf c e l l s . Scale: a - c, f; I 100um I d, e, g - i ; I •• 100um I ' 317 • I 318 F i g . 66a - e. The stem anatomy and the var i a t i o n i n the alar c e l l s of Hygrohypnum ochraceum. Scale: a; | 100um { b - e; I 100um \ 320 4-Fig. 67. Hygrohypnum ochraceum 321 E x s i c c a t i Examined A l l e n , Mosses of the Cascades Mountains, Washington 139b. (MICH, NY, MIN, USA, TENN) 140 as Hypnum pal u s t r e . (NY, H. ochraceum i n part) Austin, Musci Appalachiani #437 (NY) Bauer, Bryotheca Bohemica #69 as Hypnum ochraceum. (C, LE, S-PA)= #267 as Hypnum ochraceum. (C, H, LE, S-PA) Musci europ. et. amer. e x s i c c a t i #2186. (BRNM) Musci europaei e x s i c c a t i #644 as Hygrohypnum ochraceum var. complanatum f o . l a t i f o l i a Roth. (BNM, H) #645. (BRNM, H) #646. (BRNM, H) #647. (BRNM, H) #1283. (BRNM) #1284. (BRNM) Brotherus, Bryotheca Fennica #85 as Hygrohypnum ochraceum. (LE) Grout, North American Musci Pleurocarpi #111. (CANM, H-BR, MO, NY S-PA, UC, UBC) # l l l a . (H-BR, NY, USA, MICH, TENN, UC, MIN, MO) #240. (H-BR, NY, USA, MICH, TENN, UC, MIN, MO, WTU) #278. (S-PA: H-BR, NY, USA, MICH, UC, MIN, MO) #299. (H-BR, USA, MICH, TENN, UC, MIN, MO) #380. (H-BRf-NY, USA, TENN, UC, MIN, MO) #386. (H-BR, NY, USA, MIN, TENN) #467. (S-PA, NY, USA, MICH, TENN, UC, MIN, MO) North American Musci Pleurocarpi Supplement #62. (MIN, UC) Herausgegeben von der k g l . botanische Gess e l l s c h a f t i n Regensburg, Musci exsiccata Bavarica Bryophyta #380. (S-PA) Husnot, Musci Galliae. #496. (NY, S-PA) Kerner, F l o r a Exsiccata Austro-Hungarica #3511 as Hypnum ochraceum. (C, LE, S-PA, BP, H, NY) Limpricht, Bryotheca S i l e s i a c a #91. (BP, LE, S-PA) #348. (BP) #349. (BP, LE, NY, S-PA) Lisowski, Bryotheca Polenica Fasc. XI, #320, (BP, H, S-PA) #321. (H) #322. (BP, H) Fasc. XIV, #393. (BP, H, LE, S-PA) #394. (BP, H) Fasc. XX, #549. (BP, S-PA) Fasc. XXX, #792. (BP, S-PA) #793. (BP) Fasc. XXXI, #821. (BP, H, S-PA) #822. (S-PA) Macoun, Canadian Cryptogams #141 as Hypnum p a l u s t r e . (USA) Canadian Mosses #397. (CANM, H, MICH, MO, NY, LE, UBC) #490. (MO) Canadian Musci #360. (MICH, MIN, UC, USA, TRTC, S-PA) #396. as Hygrohypnum alp e s t r e . (C) #898. as Hypnum p a l u s t r e . (USA) 322 Matouschek, Kryptogamae exsiccatae #1287 as Hypnum ochraceum, CC, H, LE, S-PA)>'. #1288 as Hypnum ochraceum var, f i l i f o r m e . (H) Migula, Cryptogamae Germaniae, Austriae at Helvetiae exsiccatae #270 as Hypnum ochraceum. (C) #271 as Hyprium ochraceum var f i l i f o r m e . (C, MIN) #375 as Hypnum ochraceum. (C) Muller, Westfalien Laubmoose #244. (BP, S-PA) Noguchi and H a t t o r i , Musci Japonica #705. (S-PA) Petrak, F l o r a Bohemiae et Moraviae exsiccata Lfg. 4, Nr. 175 as Hypnum ochraceum var. uncinatum. (C) Pilo u s , Musci cechoslovenici e x s i c c a t i #84. (H) #111. (H) #142. (H) #168. (H) #239. CH) #428. (H) #690. (H) #705. (H) #707. (H) #757. (H) #1184. as Hygrohypnum ochraceum var. uncinatum. (C,H) Piper, Musci Occidentali-Americani #79 as Hypnum pa l u s t r e . (USA) Rabenhorst, Bryotheca europaea #693. (S-PA) #693b. (S-PA) #693c. (S-PA) #693e. (S-PA) #844 as Limnobium ochraceum. (C) Slezske museum v Opave-Museum S i l e s i a e , Sectio Botanica Gpava, Musci e t Hepaticae e x s i c c a t i #94 as Hygrohypnum ochraceum. CC, BP, S-PA) S u l l i v a n t and Lesquereux, Musci B o r e a l i Americani Ed. I, #305, (MICH, NY) Ed. I I , #452. (MICH, NY, NYS) Selected Specimens Examined Canada B r i t i s h Columbia Queen Charlotte Islands, Moresby Is., S. side of Takakia Lake; Schofield 25200. (UBC) Queen Charlotte Islands, Graham Is., head of Dawson I n l e t ; Schofield & Vaarama 24619. (UBC) Mt. Seymour P r o v i n c i a l Park; Sc h o f i e l d 19948. (UBC) Prince Rupert Area, Hays Mt., Kaien Is.; Schofield and Sharp 25840. (CANM, UBC) Vancouver Island, Port Renfrew, San Juan Point; Schofield 13730 (UBC, TENN, NY) Caribou D i s t r i c t , Mt. Ishpa; Boas 654. (CANM, UBC) Kokanee Glacier Prov. Park; MacFadden Aug. 1924. (UBC, TENN, USA) Vancouver Island, Burman Lake; Boas 218. (UBC) 323 British Columbia (continued) Revelstoke Area, Big Bend of the Columbia River, Selkirk Mtns.; MacFadden 3863. (CANM, UBC) Wells Gray Prov. Park, Battle Mtn., S. of Fight Meadows; L. and T. Ahti 14154. (H, UBC) Garibaldi Prov. Park, Sentinel Glacier Area; Schofield 32947. (CANM, UBC) Mt. Cheam; Macoun 12 Aug. 1901. (CANM) Gr i f f i n Lake; Macoun 10 Aug. 1889. (CANM) Rogers Pass; Macoun #370, 2 Aug. 1890. (CANM) Alberta Jasper Natl. Park, Tonquin Valley; MacFadden 3871. (CANM) L i t t l e Slave Lake; Macoun 1872. (CANM) Waterton Lakes Natl. Park, N. shore of Cameron Lake; Hermann 20560. (NY) Ontario Muskoka Dist., Muskoka R., High Falls; Hand 758. (CANM, TENN) Algoma Dist., Agawa Bay, Lake Superior Prov. Park; Ireland 4791. (CANM, USA) Thunder Bay Dist., S side of St. Ignace Is., Garton 7028. Algonquin Park, Brewer Lake; Cain 764. (TENN, TRTC) Sarnia; Macoun 11 Aug 1891. (NY) Bruce Peninsula, Sauble Falls; Moxley 24 May 1936. (NY) Haliburton Dist., Irondale; Cain 5000. (TRTC) Quebec NE of Luskville, Luskville Falls; Ireland & Ley 10018. (CANM) Pare du Mont Tremblant, E. of Lac Monroe; Hermann 16747. (CANM) Gaspe Bay, near Fort Prevel; Crum and Williams 10831. (CANM) Gracifield, near Blue Lake; Crum 8271a. (CANM) Mont St. Hilaire; Dupret 8 Sept 1906. (CANM) Montmorency River; Macoun 520. (CANM) Argenteuil Co., Lakefield near La Chutte; Cook 10. (CANM) Comte de Matane, Lac a' Foin; Boivin & Blaind 693. (MICH) Rimouski Co., Pointe au Pere; Lepage 13535. (USA) Beauceville; Anselme 15 July 1943. (TRTC) Nova Scotia Annapolis Co.Y Kejimkujik National Park, M i l l Falls of Mersey R., Ireland 12473. (ALTA, CANM) Inverness Co., Cape Breton Highlands Natl. Park, Buelach Ban Falls; Ireland 11848. (CANM) Colchester Co., Upper Brookside, NE of Truro; Smith 2 July 1931 (MICH) Antigonish Co., near James River Station, Glen Bard; Grout 6431. (MICH) Kings Co., White Rock Dam; Erskine 53c2462. (NSPM) New Brunswick Albert Co., Fundy Natl. Park, road to Marven L.; Ireland 11247. (ALTA, CANM) Queens Co., Caanan Forks; Moser 1889. (CANM) Madawaska Co., L i t t l e R., Habeeb 21 June 1944. (NY) Bass River; Fowler 30 May 1870. (NY) Newfoundland Waterford R. at Browning Park; Damman 6. (CANM) Broad Cove; Waghorne 1034. (CANM) Beechy Cove; Waghorne 20 Aug 1895. (NY) 324 Labrador Battle Harbour; Waghorne 410. CCANM) L'Anse au C l a i r ; Waghorne 31 July 1893. CNY) Yukon Territory Bonanza Creek; Williams 9 June 1899. (NY, USA) Hunker Creek; Macoun 26 July 1902. (S-PA United States Alaska Adak Is.; Jordal 2759. (USA, TENN) Yakutat; S t a i r 4928. (TENN) Amchitka I s . , near C y r i l Cove; Sjacklette 7178. (MICH) Attu I s l . , near Massacre Bay; Jordal and M i l l e r 2986. (MICH) Mt. McKinley Natl. Park, Eilson; Sherrard A22. (USA) Juneau, Montana Creek; Hermann 22087*5. (USA) Sitka; Macoun 26 Sept 1891. (NY) Anchorage, Fi r e Lake; Lepage 9-6-48. (NY) Cape Lisburne; Steere & Crum 20540. (NY) Washington Jefferson Co., Olympic Natl. Park, Mt. Olympus; Becking 5309992. (WTU) Grays Harbor Co., Westport; Foster Aug. 1909. (WTU) Mt. Rainier Natl. Park. Paradise Valley, Frye 27. (WTU) Yakima Co., Mt. Adams; Lawton 5176. (WTU) Chelan Co., Stevens Pass Area; Frye 3252. (WTU) Oregon Hood River Co., Mt. Hood Natl. Forest north of Bennett Pass; Lawton 3226. (WTU) Newport, at Stocker M i l l ; Daughtery 8 Aug. 1921. (WTU) Clackamas Co., SW slope of Mt. Hood; Hermann 18705. (WTU) Klamath Co., Crater L. Natl. Park; Mueller 6727. (HSC) Union Co., Wallawa Mtns., SE of Union; Hermann 18872. (USA) Wallawa Co., SE of Imnaha, Hat Point; Hermann 18932. (USA, NY) Ca l i f o r n i a T r i n i t y Co., Coffee Creek near South Fork; Norris 9361. (HSC) Siskiyou Co., Marble Mountain Wilderness Area; Spjut 1194. (HSC) Calaveras Co., Stanislaus Natl. Forest, S. of Alpine L.; Mueller 6699. (HSC) Eldorado Co., Echo Lake; Conard 5 Sept 1947. (MICH) Shasta Co., Lassen Natl. Park near Summit Lake; Koch 1923. (MICH) Mono Co., H.M. Hal l Natural Area; Catcheside 47120. (MICH) Plumas Co., Plumas Natl. Forest, N. f o r t of Feather R., Koch 1893. (NY) Mariposa Co., Big Tree Grove Idaho Boundary Co., Bonner's Ferry; Frye 9 Sept. 1928. (WTU) Lemhi Co., N. of Gibbonsville; Frye 1 Sept. 1939. (WTU) Kootenai Co., Hope; Sandberg Aug 1892. (NY, USA) Custer Co., Sawtooth Wilderness Area, Forks of Baron Creek; Morton 8584. (USA) Montana Mineral Co., Henderson; Frye 20 Aug 1925. (WTU) Glacier Natl. Park, Logan Pass; Hermann 20654. (WTU) Utah Above Sal t Lake; Evans 15 Aug. 1924. (NY) Wasatch Mtns. N. of Ogden R., Kelley 4 Aug. 1925. (NY) 325 Nevada Elko Co., Humboldt N a t l . Forest, SW of Mountain C i t y , Lawton 2710. (NY, TENN, UBC) Arizona Apache Co., Mt. Baldy; P h i l l i p s & Haring 9071. (MICH) Graham Co., Pinaleno Mtns., MT. Graham; Haring and Darrow 25 July 1943. Wyoming Fremont Co., W. of Dubois, Tworoger Pass; Frye 22 June 1931. (WTU) Carbon Co., Medicine Bow Mtns. SE of Morgan; Hermann 17809. (USA) Teton Co., Teton N a t l . Pk., Cascade Canyon; Cain 4547. (UAC, TRTC) Yellowstone National Park; Roell 2 Sept. 1888. (LE) Colorado Larimer Co., Rocky Mtn. N a t l . Park; Longs Peak; Kiener 7310. (MICH) G i l p i n Co. near Tolland; Grout, July 1914. (USA) Mount A x t e l l Area; Tidestrom 8 Aug. 1910. (USA, S-PA) San Juan Co., San Juan Mtns., SSW of S i l v e r t o n ; Hermann 23303. (NY) Michigan Keweenaw Co., near Horseshoe Harbor; Steere Sept. 1935. (MICH) Alger Co., Au Train Point; Steere 471. (MICH) Ontonagon Co., Porcupine Mtns., Steere and Nichols 20-27 Aug 1935 (MICH) Minnesota Cook Co., Grand Marais, Rosebush F a l l s ; Holzinger 28 July 1902. (NY,S-PA) Pennsylvania Cambria Co., near Summit; James Aug. 1859. (TENN) Monroe Co., Pocono Forks; James Nov. 1868. (TENN) Pike Co., Saw Creek near mouth of Big B u s h k i l l ; Glime 30 July 1965.(MICH) Chester Co., W. of Oxford; S t a i r 6/1/47. (MICH) Montgomery Co., Evansburg; Taylor 2501. (MICH) Bradford Co., Bennett Brook; Burnett 18 Aug 1895. (NY) New York Greene Co., E. of Haines F a l l s V i l l a g e ; Hermann 14440. (TENN, TRTC) Essex Co., Mt. Marcy T r a i l ; Smith 17 Aug 1934. Yonkers;-T-Howe. (MICH, S-PA) Lake George, Hulett's Landing; J e l l i f f e 21 June 1889. (NY) Sand Lake; "C.H.P." 1865. (NY) Penn Yan Saw M i l l ; Bumstead. (NY) Vermont Manchester Co., Downer's Glen; Thompson 2 Sept 1934. (MICH) New Hampshire Marlow, near Sand Pond; A l l e n & S t a i r 8/3/39. (MICH) White Mountains, near Mt. Madison; Taylor 2496. (MICH) Mt. Belknap, G i l f o r d ; Carter 5 Sept. 1904. (USA) Maine Mount Katahdin, c l i f f a t F a l l s above Camp Baxter; A l l a r d 5171 (MICH) Cumberland; C o l l i n s 2500. ( M I C H ) Acadia N a t l . Park, Mt. Desert; Taylor 3357. (MICH) Oxford Co., Canton Point; P a r l i n 11581. (NY) Massachusetts Berkshire Co., Plantain Pond B r i t t o n 13 Aug. k901. (NY) Essex Co., Amesbury; Huntington 4. (NY) Connecticut New Haven, Wintergreen F a l l s ; A l l e n 15 June 1878. (NY) Rhode Island Greystone; C o l l i n s 2138. (MICH) Maryland Garrett Co., NNW of Oakland, Swallow State F a l l s Forest, Hermann 14917. (USA) 326 New Jersey Rosemont; Best 1894. (NY) V i r g i n i a Giles Co., Mountain Lake; Sharp V267. (NY) West V i r g i n i a Blackwater F a l l s ; Smith 5 July 1878, (NY) Greenland Disco Island, Diskofjord Kuanit; P o r s i l d 949. (NY) Kvarak v i d Fredersksdal Marti; Vahl. (H-BR) Great B r i t a i n Cornwall, near Penzance; Curnow Sept. 1863. (S-PA) Lancaster, Todmorden; Schimper 1865. (S-PA) York, Hebden Bridge; Hunt May 1865. (H, S-PA) Wales North Aber; Wilson May 1863. (S-PA) Cum Idwal; Yong 1932. (S-PA) Scotland Braemar; Head of Far Easedale; Binstead Oct. 1924. (H) Ireland Killarney; Lindberg July 1873. (H) France Vogeses; Pierrot J u l i 1884, (S-PA) Haute Savoie, Bord du hac du Breveu; Guinet Auot 1888. (S-PA) Austria Salzburg, Gastein; Swanziger. (S-PA) T i r o l Achenseehof; Suse Aug. 1895. (S-PA) Steiermark, bei Schladming; Breidler 5/9/1884. (S-PA) West T i r o l , Moosbachthal bei St. Anton am Arlberge; Schiffner 7.8.1907. (BP, S-PA) Germany Thuringer, Overhof; Rose. (S-PA) Berchtesgaden; Suse 1 Sept. 1895. (S-PA) Bayerischen Wald (Hauptberg); Freiberg 25 Oct. 1955. (S-PA) Harz; Hespe 240. (S-PA) Belgium Bouillon; Cardot 10 J u l l i e t 1881. (H) Czechoslovakia Vysoke Tatry, v a l l i s Vel Studena; Vajda 13 July 1961. (BP) Tatra Minor, prope Luchy; Vajda 10 Oct. 1965. (BP) Poland S i l e s i a sepentia, Montes Jeseniky; Duda 30 July 1950. (BP) Sudety Mountains, as Bryotheca Polanica Fasc. XIV #393 (BP) Montes Carcontici, as Bryotheca Polonica #320. (BP) Hungary Carpath. Meridion, In rupibus i r r i g a t i s r i v i Riu mare Gura Zlata, montes Retyezat; Vajda 12 July 1968. (BP) Spain Hispanien centr. Sierra de Gredos; Levier 12 Aug. 1878. (NY, S-PA) Portugal Minho Prov., V-la Celova de Cerveira eutre Beuporta e campos vale v o l l a do a norte flutuando presa sos granitos nos cursos de qua aqua corrente; Leha 20078. (S-PA) Faroes Sydiro Traugesvaag; Jensen 12/8/1896. (H, S-PA) Bordo, Gravendal; Jensen 17 May 1896. (H, S-PA) 327 Iceland Lladara, Nord I s l . , Davidsson 30 June 1903, (S-PA) Tunga Fos; Feddersen 25 June 1886. (H) N. l i s . , Eyjafjorden; Davidsson 21 Aug. 1897. (H, S-PA) Bear Island Beeren Eiland, Nordhamnen; Bergren 1868. (C, H, S-PA) Norway Gudbrandsdalen; Berggren June 1865. (S-PA) Gausta; Jaederholm July 1895. (S-PA) Telemark, Bo L i f j e l l ; Stormer 30 Aug. 1937, (S-PA) Troms, Nordreisa, Nyholmen; Ar n e l l 22 Aug. 1891. (S-PA) Rogaland; Hakelier 20 June 1958. (S-PA) Hardanger; Greir 2 Aug. 1894. (S-PA) Nord Trondelag; Hulphers 1 Sept. 1934. (S-PA) Nordland; A r n e l l 20 July 1869. (S-PA) Finmarken; Zetterstedt 6 Aug. 1868. (S-PA) Sweden Skane; Gronvell J u l i 1887. (S-PA) Halland; Hjarne 14 May 1942. (S-PA) Oestergotland; Dusen 21 June 1889. (S-PA) Vastergotland; Hulphers J u l i 1930. (S-PA) Bohuslan; Thedenius Juni 1883. (S-PA) Dalsland; Larson 7 Sept. 1916. (S-PA) Narke; Waldheim 6 June 1931. (S-PA) Sodermanland; F l o r i n 25 Aug. 1929, (S-PA) Vastmanland; Tarnlund 14 Sept. 1944. (S-PA) Varmland; Johannsson 30 June 1928. (S-PA) Dalarna; Moller 13 July 1909. (S-PA) Halsingland; Collinder June 1878. (S-PA) Medelpad; Collinder 18 Sept. 1889. (S-PA) Harjedalen; Einander 9 Aug. 1892. (S-PA) Jamtland; Seth 21 July 1895. (S-PA) Angermanland; Ar n e l l 30 July 1906. (S-PA) Norrbotten; Moller 5/8/12. (S-PA) Asele Lappmark; Hulphers 15 July, 1943. (S-PA) Lycksele Lappmark; Hulphers July 1933. (S-PA) Lule Lappmark; Hulphers J u l i 1935. (S-PA) Torne Lappmark; Ekstrand 5 Aug. 1880. (S-PA) Finland, Helsingfors; Lindberg 30 June 1868. (S-PA) Tavastia australis;' C o l l i n July 1887. (S-PA) Osterbotten; Lackstrom 5 July 1873. (S-PA) Lapponia Keminsis; Hult 12 July 1877. (S-PA) Kuusamo; Brother 14 July 1883. (S-PA) Utsijokk; Hult 30 July 1870. (S-PA) Kemin Lappmark; Ulvinen 11 Aug. 1962. (S-PA) Karelia a u s t r a l i s ; Fagerstrom 25 Aug, 1964. (S-PA) Savonia borealis; Kotilainen June 1917. (LE) Spitsbergen Green Harbour; Berggren 1868. (H, S-PA) Soviet Union Cuba Vologda, d i s t r . Totemsk; Korezagin 29 July 1926. (S-PA) Siberia, Jenesei, Asinova; A r n e l l 4/7/1876. (H, H-BR, LE, NY, S-PA) Syd-Kamchatka; Hulten 10/9/1921. (S-PA) Siberia, i n v a l l e flum Lena, Kumachsur; Nilsson-Ehle 26 July, 1898. (LE, H, S-PA) 328 Soviet Union (Continued) Transbaikalia d i s t r . Taxhita, Yamarovka; Mikhno 20 July 1905 (H-BR) Amur Region, Zei i n jugo Tukuringz; Kuseneva 315, (H-BR) A l t a i d i s t r . , Birsk; Kursky 26 June 1909. (Hr-BR) Lapponia tulomensis, prope Alexandrovsk; Savicz, Savic & Nykolsky 28 (S-PA) J e n i s e i , Mjelnitsa; A r n e l l 12 July 1876. (S-PA) Jenesei, Plachino; A r n e l l 23 July 1876. (S-PA) Jenesei, Patagovskoye; A r n e l l 25 July 1876. (S-PA) Jenesei, Antisferova; A r n e l l 27 July 1876. (Sr-PA) Jenesei, Tolstoinos; A r n e l l 18 Aug. 1876. (S-PA) Jenesei, Alinskoye; A r n e l l 9 July 1876. (S-PA) Lapponia imandrae, i n alpp. Umtek; Kihlman 24 July 1892. (S-PA) Lapponica murmanica; Brotherus J u l i 1885. (S-PA) Lapponia varsugae, P j a l i t s a ; Kihlman 16 Aug. 1889. (S-PA) Lapp, or., Jokonga; Brotherus July 1872. (S-PA) K a r e l i a lodogensis, Svanlahte; Huuskonen 28 July 1937. (S-PA) Mongolia Orchon; Lewin 17 Aug. 1891. (H-NR) Japan Twashiro Prov., Mt. Bandai; Usmatsu May 1908. (H, MICH) Eniwa Prov., Mt. Tburi; Takewaki 2/11/1921. S-PA, H) Shinano Prov., Mt. Shirouma; Ishiba 17 Aug. 1909. (H-BR) 329 Hygrohypnum eugyrium (Schimp.) Loesk., Verh. Bot. Ver. Brandenburg 46: 198. 1905. Holotype: Germany, Geroldsau prope Baden-Baden; Schimper 1854. (BM) Limnobium eugyrium Schimp., Bryol. Eur. 6:73. 579. 1855. Hypnum eugyrium (B.S.G.) S u l l . ejt Lesq., Musci Bor. Am. 66. 1856. Limnobium rufescens Schimp. i n S u l l . i n Gray, Man. Bot. N. U. S. ed. 2:671. 1856. nom. nud. i n synon. Hypnum eugyrium (B.S.G.) Schimp., Syn. 639. 1860. hom. i l l e g . Hypnum eugyrium var. mackayi Schimp. Syn. ed. 2:782. 1876. Amblystegium eugyrium (B.S.G.) Lindb., Musci Scand. 33. 1879. Calliergon eugyrium (B.S.G.) Kindb,, Eur. N. Am. Bryin. 1:83. 1897. , ' Amblystegium. eugyrium var ..mackayi- iSchlmp..) Braithw., B r i t . -.::M©ss Fl.-r-3:62. 1898. Hygrohypnum mackayi (Schimp.) Loesk., Moosfl. Harz. 321. 1903. Limnobium mackayi (Schimp.) Roth, Eur. Laubm., 2:648. 56f.5. 1905. Hygrohypnum eugyrium var. mackayi (Schrimp.) Broth., Nat. P f l . 1(3): 1040. 1909. Names treated as synonyms elsewhere, but for which the l i t e r a t u r e was unavailable for assessment during t h i s study. Hypnum mackayi (Schimp.) B r e i d l . , M i t t i e l . Naturw. Ver. Steierm. 28:217. 1882. Hyggrohypnum engyum Broth, ex H i l l , Ann. Sc, Univ. Besacon . ser. 2 Bot, 3:167. 1954. Names of certain taxa for which the l i t e r a t u r e was examined, but 330-found inadequate for e f f e c t i v e assessment of the taxon i n the absence of the type specimen. Limnobium eugyrium var. nervosum R o e l l , Hedwigia 46:206. 1907. Plants forming loosely, often e a s i l y fragmenting patches or t u f t s , sometimes t i g h t l y woven, color variable, yellow-green, pale green, bright green, often exhibiting a golden-brown to deep metallic red mottling, plants frequently becoming a dark red, reddish-brown or brown with age, most plants exhibit a s t r i k i n g s a t i n - l i k e l u s t r e or sheen. Stems (1) 2-4 (6) cm long, prostrate or ascending near the t i p , older extremities may become denuded with age, stems i n i t i a l l y green or yellow-green, but becoming red or reddish-brown with age. Branching i r r e g u l a r , branches mostly ascending, sometimes almost erect; often the older, but s t i l l f o l i o s e portions of both the stems and branches become clogged with s i l t and sand. Stem cross sections revealing 3 to 5 rows of small, thick walled c o r t i c a l c e l l s , color varying with age, the epidermal c e l l s frequently s l i g h t l y less darkly pigmented than the adjacent c o r t i c a l c e l l s , further the outer tang-e n t i a l w a l l of the epidermal c e l l s i s often s l i g h t l y thinner walled; medullary c e l l s are i n i t i a l l y t h i n walled and hyaline, but become somewhat incrasate and discolored with age; central strand present. Rhizoids few to none, a r i s i n g from the bases of ventral stem or branch leaves. Leaves variable; ovate, oblong-lanceolate to lanceolate, straight or falc a t e ; (0.8) 1.1 - 1.8 (2.0) mm long x (0.3) 0.5-0.8 (1.2) mm wide; leaves generally crowded or among plants or stems with lanceolate-falcate leaves somewhat distant, variously appressed or loosely imbricate or loosely spreading; attitude changing l i t t l e from the wet to the dry condition; leaves generally quite concave though s l i g h t l y less so i n some 331 more lanceolate leaves; leaf base usually clasps the stem; margins variable, entire or a few small teeth on the apex, plane or variously folded or inrolled, one side may often be infolded as a wing, in which case that side of the leaf which exhibits the fold i s situated closest to the dorsal side of a more or less prostrate stem or branch or both margins may be inrolled in the upper half creating a tubulose condition which i s common among more lanceolate leaves; the overall leaf configuration i s decidely modified by the clasping leaf base; Apex variable, acute, abruptly or gradually long tapering, margins often inrolled slightly below apex giving the impression of an apiculus, entire, or with a few teeth in the extreme tip; costa usually short and double, frequently double with one or both arms reaching midleaf, rarely single to mid leaf or beyond and/or forked. Aerolation variable; median leaf cells fusiform-flexuose or linear flexuose; 30-80 um long X 4-6 um wide, separating into two groups geograph-i c a l l y , North American plants usually 45 to 75 um X 4 to 5 um., European plants usually 30 to 62 um. X 4 to 5 um.; cells becoming shorter or changing l i t t l e toward the apex; ce l l s toward the base variable, becoming shorter or longer, but increasing in width only slightly; basal cells generally strongly pitted; alar region composed of 6 to 12 enlarged or inflated, usually excavated, quadrate to rectangular c e l l s , which form a clearly defined group, the cells hyaline or become bright dark red or reddish-brown with age, the marginal alar c e l l s are always thin-walled while the inner alar cells are regularly incrassate and occasionally pitted, the pigmen-tation upon aging of the incrassate cells may become so intense as to obscure the c e l l lumina. Plants monoicous; perigonial leaves broadly ovate, up to 0.8 mm long, abruptly accuminate; inner perigonial leaves deeply concave-imbricate, margins entire or sometimes weakly serrulate in the apex, ecostate; outer 3 3 2 and middle p e r i c h a e t i a l leaves ovate to broadly ovate, generally tapering gradually to a long point, apex e n t i r e or frequently coarsely serrate, erect or s l i g h l y spreading, the upper h a l f twisting upon drying; inner p e r i c h a e t i a l leaves erect long l i n e a r lanceolate, tapering to an acute or accuminate, e n t i r e or coarsely serrulate apex, 2 to 4 weakly to strongly developed p l i c a e , costa v a r i a b l e , absent, short, double and f a i n t , double to midleaf, infrequently s i n g l e to midleaf. Seta 13 to 26 mm long, yellowish brown, to red, smooth, when wet erect to s l i g h l y arcing, twisting when dry. Capsule t y p i c a l f o r the genus. Peristome t y p i c a l f o r the genus, annulus large to 2 to 3 rows or c e l l s , dehiscent; spores 12 to 20 um; f i n e l y p a p i l losd; 2 to 3 slender, f i n e l y p a p i l l o s e - c i l i a . Hygrohypnum eugyrium i s a very c l e a r l y defined species. Several features are u s e f u l i n diagnosing the species, the most important of which i s the nature of the a l a r c e l l s . The a l a r c e l l s are c h a r a c t e r i s -t i c a l l y quadrate to rectangular and i n f l a t e d (Fig. 69 h - i ) . In no other species i s the genus are the a l a r c e l l s so r e g u l a r l y i n f l a t e d . In most cases the a l a r c e l l s are also conspicuously excavated. When young the a l a r c e l l s are hyaline, but age they acquire a very c h a r a c t e r i s t i c red or reddish brown c o l o r . The walls of the marginal a l a r c e l l s are t h i n (Fig. 6 9 b ) . However, the i n t e r i o r a l a r c e l l s r e g u l a r l y become incrassate with age and frequently p i t t e d (Fig. 69i) . Leaves selected f o r examin-ation of the a l a r c e l l s should be taken only from well developed stem or branch segments. The l u s t r e exhibited by H_. eugyrium i s frequently useful as a f i e l d or d i s s e c t i n g microscope character. The apparent nature of the c e l l w a l l 333 material on the leaf surface and the areolation pattern seem to impart an almost s a t i n - l i k e sheen to many plants. The stem cortex of most species i n the genus i s composed of several rows of small, thick walled, usually darkly pigmented c e l l s . Among those species with such stems, Hygrohypnum eugyrium varies s l i g h t l y . Often the outer most layer of c o r t i c a l stem c e l l s i s s l i g h t l y less p i g -mented than inner c o r t i c a l layers. Further, the outer tangential wall of the outer most row of c o r t i c a l c e l l s i s thinner than i t s inner tangential w a l l or either of i t s r a d i a l walls (Fig. 69g). Limpricht (1904), Roth (1905), Brotherus (1923) and Nyholm (1965) also noted t h i s phenomenon. The leaves of Hygrohypnum eugyrium, l i k e those of other spepies i n the genus, are variable. The leaf shape varies from ovate (Fig. 68g), oblong-lanceolate (Figs. 68, d & h) and lanceolate (Fig, 68f). The attitude of the leaves upon the stem varies from appressed or loosely imbricated (Figs. . ,68>e .) to spreading (Fig. 68e) . The leaf base may be plane or strongly clasp. Strongly clasping leaf bases are often accentuated i n strongly falcate leaves. The leaf margin i s entire except i n some weekly serrulate leaf apices". The margin may be variously plane, infolded along one side as a wing (Fig. 68 g ) or variously i n r o l l e d along both sides (Fig. 68 j ). The leaves may be plane or concave. The varying degrees of marginal i n f o l d i n g or i n r o l l i n g may accentuate the o v e r a l l concavity. The apex i s acute,varying from abruptly to gradually long tapering. The apex may be modified through the influence of the i n r o l l i n g of the leaf margin and the amount of leaf concavity. In cases where one or both margins are i n r o l l e d the apical acuity may appear sharper than i t r e a l l y i s (Fig, 68 f, g & j ) . In plants where both margins are i n r o l l e d the i n r o l l i n g often ceases just below the apex thus imparting an apiculate appearance to the leaf (Fig. 68 g & h). 3 3 4 The costa of Hygrohypnum eugyrium i s variable. Usually i t i s short and double. Occasionally i t may be double with one or both arms reaching midleaf or rarely single to s l i g h t l y beyond midleaf with one or two l a t e r a l forks. The median leaf c e l l s seem to indicate that the species may be responding to some disruptive selection pressure. The median leaf c e l l s range from 30 to 80 um long X 4 to 6 um wide over the world wide range of the species. North American plants vary from 32 to 80 um X 4 to 6 um but usually l i e between 45 to 75 u X 4 to 5 um. European plants, on the other hand, range from 30 to 75 um X 4 to 5 um usually occurring between 30 and 62 u. X 4 to 5 um. The lengths of the median leaf c e l l s c l e a r l y overlap, but the mean lengths seem to be off s e t from one another. Schimper (1855, 1876) and Grout (1931) attempted to relate ovate and oblong leaves to a stem pos i t i o n and lanceolate leaves to branches. The present study was unable to substantiate these observations. Both leaf forms have been observed along ind i v i d u a l stems and on d i f f e r e n t branches attached to a common stem. Schimper (1876) described Hypnum eugyrium var. mackayi based on a Mackay c o l l e c t i o n from Tork Waterfall near K i l l a r n e y , Ireland i n 1865. One specimen bearing these data i s at S-PA. In the Schimper herbarium at BM i s a second specimen bearing s l i g h t l y d i f f e r e n t data. The lab e l reads "Hypnum mackayanum," i n mollibus ad cataractum, Turk Waterfall prope Kil l a r n e y , leg i n i t i o J u l i 1865. No co l l e c t o r i s indicated. Also present i n the Schimper herbarium are Holmgren, Nowell and Lamy coll e c t i o n s as ci t e d i n Schimper"s description. The two small fragments comprising the Mackay c o l l e c t i o n are unusual for the plants aressmall i n terms of the many specimens examined i n the present study and the leaves are strongly falc a t e . Schimper characterized the variety as a robust plant, less soft 335 than the parent v a r i e t y and bearing broadly oblong, les s acuminate leaves. So too were the leaves described as secund or s l i g h t l y so or erect spreading, though s l i g h t l y d e flected l a t e r a l l y . The specimen at BM f o r which no c o l l e c t o r was c l e a r l y indicated agrees with the Schimper des-c r i p t i o n . The large leaves of the so c a l l e d "Hypnum mackayanum" are about 1.6 to 1.7 mm long, Such lengths are well short of the known 2.0 mm maximum. Other specimens bearing f a r smaller leaves agree i n a l l other characters recognized by Schimper. Therefore, Hygrohypnum eugyrium var. mackayi (Schimp.) Broth, i s not recognized by t h i s study. The specimen at BM bearing the nomen nudum "Hypnum mackayanum" i s designated as the lectotype of the v a r i e t y . This may be redundant, f o r the specimen may be the holotype, a f a c t that cannot be established c l e a r l y i n the absence of a c o l l e c t o r ' s name. The type d e s c r i p t i o n of Limnobium eugyrium var. nervosum R o e l l (1907) was examined. I t i s the basionym f o r Hygrohypnum eugyrium var. nervosum (Roell) Podp. The o r i g i n a l d e s c r i p t i o n makes no reference to a specimen and the d e s c r i p t i o n i s , i t s e l f , i n s u f f i c i e n t to e f f e c t i v e l y assess the taxon. Hygrohypnum eugyrium ssp. subeugyrium var. occidentale (Card, et Ther.) Grout i s a form of Hygrohypnum luridum. Examination of the apparent holotype a t NY c o l l e c t e d by Mm. Trelease from Muir G l a c i e r , Alaska reveals the specimen to be a julaceous, oblong-lanceolate leaved form of H. luridum. I t i s quite t y p i c a l of western North American H_. luridum and i s e a s i l y recognized by i t s numerous small, quadrate and incrassate a l a r c e l l s and the stronger, s i n g l e costa. Schimper (1855) described Limnobium eugyrium from h i s own c o l l e c t i o n taken i n 1854 at Geroldsau w a t e r f a l l i n Baden-Baden i n southwestern Germany. The specimen was reported to contain an admixture of Brachythecium 336 velutinum. Both S-PA and the Schimper herbarium at BM have specimens answering this description. A careful examination of them reveals that the specimen at S-PA i s a fragment from the one at BM. The d u p l i c i t y of the specimen is ' t fur-ther-* substantiated by thei r possession of sim i l a r admixtures of Plagi o c h i l a . The specimen i n the Schimper herbarium at BM i s redes-ignated the holotype and the one from S-PA i s treated as an isotype. Hygrohypnum eugyrium has been confused frequently with H. luridum and vegetative material of Sematophyllum marylandicum. Several features presented i n the following chart and discussion may c l a r i f y the differences among the three taxa. H. eugyrium Alar c e l l s Alar c e l l s quadrate to rectangular, regularly i n -H. luridum Alar c e l l s quadrate to short rectangular, sometimes exca-fl a t e d and excavated; often vated, rarely i n f l a t e d ; remain-becoming brown or metallic red with age. Leaf apex Sometimes bearing a few, small teeth. ing hyaline or becoming yellowish-brown with age, rarely becoming dark reddish brown. Always entire. Stem Cross Outer layer of c o r t i c a l section c e l l s less pigmented than inner ones. Outer tangen-t i a l wall of outer row of .< c o r t i c a l c e l l s thinner than inner tangential walls or adjacent r a d i a l walls. Pigmentation and wa l l thick-ness o.. c o r t i c a l c e l l s uni-form. Capsule Annulate. Exannulate. Various stem and leaf characters permit one to distinguish Hygro- hypnum eugyrium and Sematophyllum marylandicum. As pointed out i n the preceeding chart the outer layer of c o r t i c a l stem c e l l s of H. eugyrium i s d i f f e r e n t i a t e d from the inner c o r t i c a l c e l l s . The c o r t i c a l stem c e l l s of S_. marylandicum have uniform w a l l thickness and uniform p i g -mentation. Typically, the straight leaves of S_. marylandicum are lanceo-late and loosely imbricated to spreading upon the stems. The apex of the leaves of S_. marylandicum may taper abruptly or gradually to an acute, entire point. Pronounced leaf concavity i n the straight leaves of S_. marylandicum gives them a boat shaped configuration. In the leaves of H. eugyrium the frequency with which one leaf margin or another variously i n r o l l s gives an o v e r a l l impression of asymmetry to the leaves and as such a boat shaped concavity i s not apparent. The leaf a p i c e s of H_. eugyrium frequently exhibit a few small teeth. The alar c e l l s of the two species are often quite s i m i l a r , but i n young leaves of S_. marylandicum there i s a row of 2 or 3 i n f l a t e d c e l l s extending from the leaf margin across the base at the point of i n s e r t i o n . This feature seems less apparent i n older leaves. 338 F i g . 68a - j . Variation i n the habit of the shoot and leaf shape of Hygrohypnum eugyrium. a - c, e. The habit of the shoots i n the moist condition. d, f - j . Variation i n leaf shape. Scale: a - c, e; d, f - j ; I 1mm | 339 340 Fig . 69 a - i . C e l l u l a r d e t a i l of the foliage leaves and the stem of Hygrohypnum eugyrium. a - c. Leaf apices, d. Marginal lea f c e l l s e - f. Median leaf c e l l s . g. : Stem cross section. h, i . Alar c e l l s . Scale: a c 1 100um I d - f 100 um g - i IQOum I 341 342 F i g . 70. Hygrohypnum eugyrium 343 E x s i c c a t i Examined Austin, Musci Appalachiani #438 as Hypnum eugyrium. (CANM, MICH, USA, UBC) Bauer, Musci Europ. et Ameri. E x s i c c a t i #1885 as Hygrohypnum  eugyrium. (BRNM, NY) Musci Europ. E x s i c c a t i #643 as Hygrohypnum eugyrium. (BRNM) Farlow Herbarium, Reliquiae Farlowianae #586 as Hypnum eugyrium (MICH, UC, USA) Grout, North American Musci P e r f e c t i #55 as Hygrohypnum eugyrium var. mackayi. (C, CANM, MICH, UC, . USA, TENN,,F)- , . #295 (C, CANM, MICH, MIN, UC, USA, TENN, F) North American Musci Pleurocarpi #61 as Hygrohypnum eugyrium var. mackayi. (MICH, MO, UC, USA, TENN) #129 as Hygrohypnum eugyrium var. mackayi. (CANM, MO, UC USA, TENN) #323. (CANM, MICH, MIN, MO, UC, USA, TENN) Husnot, Musci G a l l i a e #693 as Hypnum eugyrium. (G) Lisowski, Bryotheca Polonica Fasc, VII #217 as Hygrohypnum eugyrium. (BP, CANM, S-PA, LE) Macoun, Canadian Mosses #496 as C a l l i e r g o n c i r c u l i f o l i u m . (USA) Canadian Musci #535 as Hypnum eugyrium. (MO, UC, USA) Museo His t . Natur. Vindobonensis, Kryptogamae exsiccatae #2600 as Hygrohypnum eugyrium var. mackayi. (BP, C, LE, NY, F) Rabenhorst, Bryotheca Europaea #650 as Limnolium eugyrium. (NY) S u l l i v a n t & Lesquereux, Musci Boreali-Americani Ed. I, #303 as Hypnum eugyrium. (MICH) Ed.II, #450 as Hypnum eugyrium. (MICH, NY, UC, F) Verdoorn, Bryophyta Arduennae Exsiccata, Nov. Belg. Indigena #17 as Hygrophyum eugyrium var. mackayi. (MO, NY, UC, F) Selected Specimens Examined Canada Quebec Gaspesian Park, Gaspe Nord, slopes of Mt. Albert; Crum & Williams, 10681. (CANM) Terrebonne Co., V i c i n i t y of Mt. Tremblant Lodge, Crum 9834. (CANM) New Brunswick V i c t o r i a Co., S. of Grand F a l l s ; Hand 55-011. (CANM) Albert Co., Fundy National Park, Dickson F a l l s ; Ireland 10735. (CANM) Grand Manan Is.; Dunham June 1914. (NY) Bass River; Fowler. (NY) Newfoundland Top S a i l Harbour; Waghorne 11 Oct 1890 as Hypnum eugyrium.(CBNJffl) Chance Cove & Greene Island; Waghorne 25 Sept. 1890 as Hypnum eugyrium. (CANM) Nova Scotia Cape Breton Island, Inverness Co,, Big Southwest Brook; Schofield & Crum 4884. (CANM) Kings Co., Black Hole; Schofield 10949. (CANM) 344 Nova Scotia (continued) V i c t o r i a Co., Cape Breton Highlands National Park, t r a i l to Framey Peak; Ireland 11726. (CANM) United States Georgia Walker Co., Cloudland Canyon, E. of Trenton; Anderson 12958 (DUKE) North Carolina Swain Co., Great Smokey Mountains National Park, Kanati Fork; Anderson S Robinson 8893. (CANM) Transylvania Co., Horsepasture Creek, Bohaynee Rd.; Anderson 13023. (CANM) Macon Co., White oak Bottoms. SE of Rainbow Springs; Robinson 12919. (CANM) Yancey Co., Middle Creek; Anderson & Robinson 9604. (CANM) Jackson Co., Upper F a l l s Whitewater River; Anderson 8697 (DUKE) Tennessee Sevier Co., Great Smokey Mountains National Park, Roaring Fork, Mt. Le Conte; Sharp 34509. (TENN) Blount Co., Great Smokey Mountains National Park, Cades Cove; Sharp 4056. (NY) Carter Co., Roan Mtn.; Sharp 5 May 1934. (TENN) V i r g i n i a Madison Co., Shenandoah National Park, near Limberfoot; Ireland 899. (CANM) Albemarle Co., Shenandoah National Park, Jones Run Creek; Ireland 2166. (CANM) Greyson Co., White Top Mountain; V a i l & B r i t t o n 29 May 1892 (MICH) Rockingham Co., Shenandoah National Park, Big Run T r a i l ; Schnooberger 3505. (MICH) West V i r g i n i a Greenback, Iron Bridge; Gray M-963. (TENN) Tibbs Run; Millspaugh 4 July 1892. (NY) Maryland Frederick Co., NW of Bethel, Catochin Mountain; Hermann 14286. (USA) Garrett Co., SW of New Germany, Whiskey Hollow; Hermann 17614. (USA) Pennysylvania Bradford, Headwaters of Bennett Brook; Burnett 26 Aug. 1894 (NY) Carbondale, Stoney Brook; Rau. (NY) Huntington Co., Masseyburg; Becking 57070142. (CANM) New York Hamilton Co., SW of Long Lake V i l l a g e ; Hermann 16886. (MICH) Marathon; Austin 1869. (NY) Essex Co., Olmsteadville, Bigby Pond; Beals 7-11 Oct. 1917 (NY) Renssalaer Co., Sand Lake; Peck 1866. (NY) Ulster Co., Phonoecia; Haring 29 June 1936. (NY) 345 Connecticut Near New Haven, Sargent's Brook; A l l e n 29 May 1880. (NY) Vermont Stratton; Grout 1 Aug. 1901. (TENN) New Hampshire J a f f r e y , Farlow; June 1903. (MICH) Maine Piscataquis Co., N. of Milo, N, end of Schoodic Lake, Hermann 19132. (USA) Camden; Crockett 18 June 1902. (USA) Oxford Co., Buckfield; P a r l i n 10027. (NY) Mt. Desert Island, Seal Harbor; White 1 July 1892. (NY) Ohio Hockings Co., Old Mans Cave, Benton Township, NE of South Bloomington; Crum 1 Sept. 1968. (MICH) Faroes Syders, near Famien; Jensen 8 May 1896 as Hypnum eugyrium var. mackayi. (CANM, LE) Great B r i t a i n Wales Merioneth; Rhodes 2060. (TENN) Bangor; Schimper. (S-PA) Carnarvonshire, Aber; Wilson 5 June 1861. (MICH) England Westmoreland, P o t t e r f e l l ; Waddell Dec. 1885i'as Hypnum eugyrium (CANM) Yorkshire, Cantley; Nowell 5 June 1861 as Hypnum eugyrium. (BM-Schimper, SjrPA) Cornwall; Schimper. (S-PA) Scotland Braemar; Richards July 1910 as Hypnum eugyrium. (S-PA) Ireland K i l l a r n e y , Turk Waterf a l l ; l e g . unspecified but presumed to be Mackey 1865. as "Hypnum mackayanum". Holotype of Hypnum  eugyrium var. mackayi. (BM-Schimper, Osotype at S-PA) Sweden Smaland, Bankeryd Alefors; Arven 2 June 1896. (BP, S-PA) Ostergotland, Motala j a Leweeuda pa straadklipps; Mosen 22 Sept 1871. (S-PA) Dalsland, Jerbo sn Hult v i d grainen v i d Svingen pra sten; Larsen 9 June 1919. (S-PA) Poland Plurium ad saxa arenacea i n r i v u l a Solinka i n t e r monter D i z i a t et Jawarnik; Lisowski 24 A p r i l 1956 i n Bryotheca Polonica Fasc. VII #217. (CANM, S-PA) Germany Baden Gerolsauer Wasserfall; Schimper 1854. as Limnobium eugyrium. (HOLOTYPE i n Schimper Herb, at BM; ISOTYPE a t S-PA) Harz, Tneseburg, i n Bovetal; Quelle 9 Sept 1900. (B) 346 Austria Steiermark, I. Keppeldorfer Bache bei Angare; Breidler 15 May 1890. (BP) Hungary Carpathian merid., In rupibus i r r i g a t i s r i v e Riu mare prope Zlata montes Retyezat; Vajada 12 July 1968. (BP) France Pierres souvant inoundres - Pres de Bouchot Gerbamont (Vesges); P i e r r a t June 1881 as Hypnum eugyrium i n Musci Galliae #693. (G) Haute Vienne, i n saxas humidis ad molendarium prope Saint-Priest-Taurion; Lamy. (BM-Schimper) Japan Honshu, Okayama Pref. Eita-gun, Usheroyama; I g i 514. (NICH) Honshu, Nigata Pref., Leg. ? 6 June 1951. (NICH, accession #112073) . 347 Hygrohypnum subeugyrium (Ren. & Card. ) Broth., Nat. P f l . 1(3):1039. 1909 Lectotype: Newfoundland, Exploits; Waghorne 16 Dec 1893. (NY) Hypnum eugyrium var. miquelonense Ren. & Card,, Rev. Bryol. 20:28. 1893. Hypnum subeugyrium Ren. & Card., Bot. Gaz. 22:52. 4f. 1896. Calliergon subeugyrium (Ren. & Card.) Kindb., Ottawa Natural. 14:80. 1900. Limnobium subeugyrium (Ren. & Card.) Roth, Eur. Laubm. 2:645. 1905. Hygrohypnum purpurascens Broth., Oefv, Finsk, Vet. Soc. Foerh. 62A(9):36. 1921. (Holotype, H-Br) Hygrohypnum eugyrium ssp. subeugyrium (Ren. & Card.) Grout, Check L i s t Pleuroc. Moss N. Am. 16. 1929, Hygrohypnum eugyrium var. miquelonense (Ren. & Card.) Grout, Check L i s t Pleuroc. Moss N. Am. 16. 1929. Plants r i g i d to soft, variously forming t i g h t l y woven, appressed mats or loosely woven patches or cushions. Color variable, stem or branch t i o s dark metallic red, bright green, yellow-green, becoming various shades of red with age, reddish-brown, maroon-red, reddish-black or brownish-black, sometimes the t r a n s i t i o n from older more darkly pigmented extremities i s quite abrupt. Stems (1) 2-5 (6) cm long, oldest extremities mostly denuded, save for a few persistent leaf bases, leaves progressively shredded toward the stem bases i n Japanese material; branching i r r e g u l a r , branches usually less than 2 cm long, f o l i o s e throughout. Stem cross section revealing 3 to 4, sometimes 5 rows of small thick-walled, yellowish to yellowish or reddish-brown c o r t i c a l c e l l s ; medullary c e l l s larger, remaining thin-walled or becoming incrassate with age; central strand 348 poorly developed or absent; rhizoids reddish, a r i s i n g from the bases of ventral stem leaves or sexual inflorescence.• Leaves variable; shape narrowly ovate to ovate or oblong to oblong-lanceolate, (0.9)1.0 -1.5 (2.0) mm long X (0.3) 0.5 - 0.7 (0.8) mm wide; fa l c a t e , secund or straight, symmetrical or sometimes asymmetrical i n the apex, i n strongly falcate leaves the upper half of the leaf folds along the midline and curves sharply and v e n t r a l l y beneath the stem, i n some cases one side of the leaf i s infolded as<$-a wing; concave, shallowly so i n broad leaves, deeply so i n more lanceolate leaves such that the apex appears boat shaped, more or less canaliculate i n falcate leaves; leaf apex variable, tapering gradually or abruptly to an acute or s l i g h t l y acuminate point, sometimes as a consequence of leaf concavity the leaf margin i n r o l l s j u s t below the apex thus accentuating a small apiculus on -, pi some accuminate apices , abruptly acute apices are regularly blunt and f i n e l y denticulate; margins entire save for a few teeth at the t i p of acuminate apices or the acute, but blunt and denticulate -apices ; costa usually short and double, sometimes weak or almost absent, rare l y single to midleaf; leaf attitude changing l i t t l e from the wet to dry condition, falcate-imbricate to strai g h t , loosely imbricate, sometimes s l i g h t l y complanate. Areolation variable; median leaf c e l l s long l i n e a r flexuose (40) 45 - 80 (114) um long X (4) 5 - 6 (7) um wide c e l l s becoming shorter toward the apex; c e l l s toward the base generally becoming shorter and wider, often strongly p i t t e d and exhibiting a yellowish pigmentation; alar c e l l s v ariable, forming an irre g u l a r group of quadrate, short rectangular or ir r e g u l a r , strongly incrassate, yellowish or reddish-brown c e l l s or a basal row of enlarged, incrassate c e l l s surrounded by a few quadrate or irre g u l a r c e l l s ; plane or frequently excavated. 349 Plants autoicous; middle and inner perigonial leaves ovate, to 0.8 mm long, acute to accuminate, sometimes s l i g h t l y squarrose, margins entire except for a few teeth i n the apex, ecostate, basal c e l l s sometimes p i t t e d ; outer and middle perichaetial leaves broadly ovate to ovate-lanceolate, squarrose i n the upper h a l f , ecostate, p l i c a t e ; inner p e r i -chaetial leaves ovate lanceolate to long l i n e r r triangular lanceolate, to 5.0 mm long, erect, margins entire save for a few fine teeth i n the apex, deeply p l i c a t e ; costa variable, ecostate, short and double, or single to midleaf. Seta yellowish-red to reddish-brown, 13 to 22 mm long, usually 17 to 20, smooth; capsule t y p i c a l for the genus. Peristome t y p i c a l for the genus; annulus present, endostome with 1 to 3 well developed c i l i a between adjacent segments; spores 11 to 19 um i n diameter, colorless to yellow green, f i n e l y p a p i l l o s e . Hygrohypnum subeugyrium i s most e a s i l y recognized by the regular occurrence of a few minutely denticulate to f i n e l y serrulate leaf apices among others that are entire (Fig. 73 a - c) i n association with the quadrate to rectangular, enlarged and incrassate and'.often excavated alar c e l l s (Fig. 73 d, g - i ) . Hygrohypnum subeugyrium varies i n leaf shape, the shape of the leaf apex, the symmetry of the leaves and t h e i r attitude upon the stem or branches, the leaf concavity and the development of the alar c e l l s . Leaf shape varies from narrowly-ovate (Fig. 71d) to oblong lanceolate (Fig. 71e.) . Ovate leaves are generally straight, but longer and narrower leaves are straight or f a l c a t e . Ovate leaves are usually broadly and shallowly concave, whereas the narrower leaves are sometimes quite deeply concave such that the leaf apex i s almost boat shaped (Fig. 71c)- Frequently, 3 5 0 one side of the l e a f i s i n r o l l e d as a wing (Figs. 71 a & b). The nature of the l e a f apex i s extremely important i n recognizing the species. However, the apex i s v a r i a b l e and d i s c r e t i o n must be used i n assessing i t . To insure that the necessary characters are seen the worker must examine the apices to ten to 25 leaves. The apex varies from gradually to abruptly acute or somewhat acuminate (Figs. 72 c & b) to abruptly acute with a blunt point (Fig. 72a). Those acute apices with the blunt point are r e g u l a r l y f i n e l y denticulate. The margins of other apices vary from e n t i r e to having few f i n e teeth at the very t i p of the apex (Fig. 73b). Among American and Scandinavian plants the whole spectrum of v a r i a t i o n r e g u l a r l y occurs i n i n d i v i d u a l plants. Among these plants the species i s diagnosed immediately by the acute, but blunt apex with the f i n e l y denticulate margins. The acute, but blunt and f i n e l y denticulate margins has not been observed, as yet, i n Japanese material. I d e n t i f i c a t i o n of Japanese material must r e l y upon the few f i n e teeth occurring d i r e c t l y i n the apex. The a l a r c e l l s are b a s i c a l l y quadrate to short rectangular and i n -crassate, but the group they form i s i r r e g u l a r i n form and extent. In some cases they form an i r r e g u l a r group of quadrate c e l l s (Fig. 73d), while i n others there may be a row of much enlarged c e l l s extending across the l e a f base s i m i l a r to some species of Semtophyllum (Figs. 73 g S h) . In the l a t t e r case the row of enlarged basal c e l l s i s surrounded by a few quadrate or i r r e g u l a r c e l l s (Figs. 73 g & h). Contrary to Renauld and Cardot's d e s c r i p t i o n , the a l a r c e l l s may be weakly excavated (Fig. 73i). Many of the inner a l a r c e l l s are quite p i t t e d . The a t t i t u d e of the leaves upon the stem i s also quite v a r i a b l e . In some cases, e s p e c i a l l y i n Scandinavian material, the leaves are somewhat 351 complanate (Fig. 71 g & h). In other cases, the leaves are decidedly falcate, (Fig. 71i) , particularly i n Japanese plants (Fig. 72 g & h). Rarely, the stem and branch tips may be hooked. Hygrohypnum purpurascens Broth, i s united here with H_. subeugyr- ium. On the assumption that these two taxa were different they were originally studied independently. Attempts to separate them in prelim-inary keys and a reexamination of tentative descriptions for each re-vealed that they agreed in almost every essential character. Agreement may be found in color, stem anatomy, leaf size and shape, median leaf c e l l size and shape, alar differentiation, seta color and length, endos-tomal c i l i a and spore size. Perhaps the most striking feature of Hygrohyphum purpurascens was the maroon red pigmentation evident in a l l specimens. However, numer-ous specimens of H. subeugyrium from eastern North America and Scandina-via exhibit very nearly the same color. Considering the var i a b i l i t y in color in other species, color does not appear sufficiently reliable to maintain the species. The nature of the leaf apex of Hygrohypnum subeugyrium and H. pur- purascens offers the only morphological feature with which the two could be separated. The acute, but blunt and finely denticulate apex has not been observed in Japanese material. In view of the greater similarity with respect to other characters the leaf apex does not seem sufficient to maintain them as separate. It i s worth noting that very few specimens bf H. purpurascens have been available for study and that as Deguchi (1973) noted,Japanese bryologists have tended to overlook this taxon. It seems reasonable to speculate that as additional speci-mens become available the acute, but blunt and finely denticulate apex may well be present, i n Japan. The holotype of Hygrohypnum purpurascens 352 Broth, i s at H-BR. In the original description Renauld and Cardot (1896) described Hygrohypjum subeugyrium i n terms of H. eugyrium and H. luridum. Although a l l the specimens of H. subeugyrium that have been examined during this study have come from material mistakenly determined as H. eugyrium, the relationship between the two taxa i s a remote one and the choice of subeugyrium as a specific epithet mistakenly implies a closer relationship. The following chart and discussion w i l l hopefully point out the important differences between H_. subeugyrium, H. eugyrium and H. luridum. E. subeugyrium H._eugyrium Leaf apex Acute, sharp or blunt, a l - Sharply acute, entire most entire or finely den- or sometimes with a few ticulate or serrulate. teeth. Alar cells Quadrate to short rectan- Quadrate to rectangular, gular, incrassate forming a regularly inflated and basal row surrounded by excavated, quadrate or irregular c e l l s . Cortical Cells uniformly small, Outer tangential wall of stem cells thick walled, evenly the outer most row of cor-pigmented. t i c a l cells slightly thinner walled and less pigmented than other walls and other c e l l s . Leaf Do not clasp the stem. Usually clasp the stem, insertion The median leaf cells of H. subeugyrium vary from 42 to 114 um long, but generally range from 60 to 75 um. However, a significant number of cells are between 80 and 95 um. This contrasts H. eugyrium i n which the median leaf cells range from 30 to 80 um with most cells lying between 40 and 62 um. In Europe most median leaf cells of H_. eugyrium occur be-tween 30 and 62 um, whereas those of H. subeugyrium are usually between 60 to 90 um. Although Renauld and Cardot (1896) compared Hygrohypnum subeugyrium 353 with E. luridum, the s i m i l a r i t y between the two taxa i s not great. The le a f apex of H_. luridum i s never toothed, or i s i t ever blunt. Renauld and Cardot (1896) described the capsule of Hypnum subeugyrium as exannu-l a t e , which would a l l y i t with H.. luridum. However, they were mistaken, f o r an annulus may be found i n young operculate capsules of Hygrohypnum =5? subseugyrium. The annulus i s evidently l o s t very soon a f t e r capsule dehiscence. The nomenclature of Hygorhypnum subeugyrium has been somewhat con-fused, f o r Renauld and Cardot described the species on two d i f f e r e n t occasions under two d i f f e r e n t names. Renauld and Cardot (1893)-originally described the p l a n t as Hypnum eugyrium var. miquelonense i n a footnote i n a l i s t of North American mosses. The type l o c a l i t y was given as Miquelon, but no specimen was c i t e d . The only known specimen bearing the v a r i e t a l name i s at NY. The specimen, c o l l e c t e d by Delamare, bears no c o l l e c t i n g date and only these b r i e f data: "Newfoundland, St. Pi e r r e Miquelon, Langlad." In the absence of a c l e a r reference to a specimen i t can only be speculated that the Delamare c o l l e c t i o n i s the holotype. However, i t i s s i g n i f i c a n t that the fragmentary specimen c l e a r l y agrees with the d e s c r i p t i o n and the assumption has been made that i f the specimen i s not the holotype, then i t i s at l e a s t representative of the v a r i e t y . Renauld and Cardot (1896) were apparently unaware that Hypnum  subeugyrium was the same as Hypnum eugyrium var. miquelonense. Their d e s c r i p t i o n of II. subeugyrium was based on a Waghorne c o l l e c t i o n of 1893 from E x p l o i t s , Newfoundland. The only known specimen agreeing with t h i s reference i s at NY. The c o l l e c t i n g date i s given as 16 Dec. 1893. The Waghorne and Delamare specimens are c l e a r l y one and the same taxon. Unfortunately, i t seems u n l i k e l y that the Waghorne specimen at NY i s the 354 holotype. Renauld and Cardot (1896) described the p l a n t as exannulate. However mistaken t h i s observation was, i t could not have been made from the NY specimen f o r i t i s completely s t e r i l e . U n t i l a bonafide holotype i s established the Waghorne specimen of 16 Dec. 1893 a t NY i s designated the lectotype. Selected Specimens Examined Canada Ontario N i p i s s i n g D i s t . , Lake Timagami, Paradise Bay; Cain 3121 as Hygrohypnum eugyrium. (CANM) Nipi s s i n g D i s t . , Lake Timagami, G u l l R.; Cain 3139 as Hygprhypnum eugyrium. (UAC, UBC) Ni p i s s i n g D i s t . , Lake Timagami, Gomphidius Bay as Hygrohypnum eugyrium. (NY) Quebec Terrebonne Co., N. of St. J o v i t e , near Mt. Tremblant Lodge; Hermann 15730 as Hygrohypnum eugyrium. (USA) Nova Scotia Cape Breton Island, v a l l e y of Barrasois; Nichols 1496 as Hypnum al p e s t r e . (NY) Newfoundland E x p l o i t s ; Waghorne 16 Dec. 1893. as Hypnum subeugyrium. (NY, l i k e l y holotype, tentative lectotype) St. P i e r r e Miquelon Leg.: D. Delamare as Hypnum eugyrium var.miquelonense. (NY, l i k e l y holotype, but t e n t a t i v e l y designated the lectotype) United States Tennessee Great Smokey Mountains National Park, Rainbow F a l l s , NE side of Mt. LeConte; Steere 10678 as Hygrohypnum eugyrium. (MICH) Cooke Co., Rich Butte Mtn.; Sharp 39177 as Hygrohypnum  eugyrium. (MICH, TENN) New York Hamilton Co., Raquette River, SW of Long Lake V i l l a g e -Hermann 16911 as Hygrohypnum eugyrium. (CANM) New Hampshire White Mountains; James July 1857 as Hypnum eugyrium. (UBC) Great B r i t a i n Scotland, A r g y l l Co., Loch Sumart, Morvern; Wallace & Crund-well 1/7/1954 as Hygrohypnum eugyrium. (CANM) Sweden Vastergotland Ostads sn. Alanda; Larsson 12 Sept. 1930 as Hygrohypnum  eugyrium. (S-PA) 355 Sweden (continued) Vastergotland Undenas, sn. Granvik, NV. om Hyttehamn; Hakelier 5 June 1966 as Hygrohypnum eugyrium. (S-PA) Bramhulte sn. Tosseryd; Soderberg 19 Aug. 1920 as Hygrohypnum eugyrium. (S-PA, UBC) Bohuslan Spekerods sn. Lundby; Larsson 6 June 1915 as Hygrohypnum eugyrium. (S-PA) Narke Hidings sn Svenskyttan; Hakelier 7 May 1959 as Hygrohypnum eugyrium. (S-PA) Halland Fjaros, Algarda; Stenholm 27 July 1922 as Hygrohypnum eugyrium. (S-PA) DaIsland Vassbrotau; Larsson 19 Oct. 1914 as Hygrohypnum eugyrium. (S-PA) Forsbacka; Larsson 20 June 1916 as Hygrohypnum eugyrium. (S-PA) Vassbotten; Larsson 27 July 1937 as Hygrohypnum eugyrium. (S-PA) Odeberg sn. Radenefors; Bergstrom 27 July 1920 as Hygrohypnum eugyrium. (S-PA) Japan Prov. Shinano, Mt. Shirouma; I i s h i b i a 17 Aug. 1949 as H_. purpurascens. (Holotype, H-BR) Prov. Tse, Mt. Kamogataka; Yasuda 8/6 1922 as H. purpurascens. H-BR) Hondo, Mt. Odaigahara; Takaki 3 Aug, 194 8 as H. purpurascens. (S-PA) Honshu, Nara Pref. Mt. Misen; Nakajima 24221 as H. purpur- ascens , (H) Shikiku, Ehime Pref., Omogo; Hattori 124 as H. purpurascens. (NICH) Aki Prov., Mt. Ege, Saeki-gun; Koyama 2059 as H. purpurascens. (NICH) Nara Pref., Odigahara, v a l l e y of Nagoya-dani; Mizutani 541 as H_. purpurascens. (NICH) Korea . - ' ^ Mt. Sokri; 870 m on wet rocks; Hong 2787, 21 Dec. 1960. (NICH) 356 F i g . 71 a - i . V a r i a tion i n leaf shape and the habit of the shoot of Hygrohypnum subeugyrium i n Europe and North America, a - f. Variation i n leaf shape. g - i . V a riation i n the habit of the moist shoots Scale: a - f; I 1mm I 9; The shoot i s approximately 1 cm long h - i ; Each shoot i s approximately 0.75 cm long 357 358 Fig . 72a - i . V ariation i n leaf shape and the habit of the shoot of Hygrohypnum subeugyrium i n Japan, a - f, i . Leaf shape, g, h. The habit of the moist shoots. Scale: a - f, i ; i l 1mm I : g, h; Each shoot i s approximately 1 cm long 360; Fi g . 73a - i . C e l l u l a r d e t a i l of the foliage leaves of Hygrohypnum  subeugyrium. a - c. Leaf apices. d. g - i . Alar c e l l s . e. Median leaf c e l l s . f. Marginal leaf c e l l s . Scale: a - c, d, g - i ; . I 100um | e, f; - I • 100um I \ 362 4-Fig. 7 4 . Hygrohypnum subeugyrium 363 Hygrohypnum montanum (Lindb.) Broth., Nat. P f l . 1(3):1039. 1909 Lectotype: Mt. A l b i s , N.H., Dr. James, 1853 (NY) Hypnum montanum Wils. i n James, Proc. Ac. Sc. Nat. P h i l a d e l -phia 7:447. 1855. horn, i l l e g . Amblystegium montanum Lindg., Musci Scand. 33. 1879. Limnobium montanum (Lindb.) Kindb., Canad. Rec. S c i . 6:74. 1894. Calliergon montanum (Lindb.) Kindb., Eur. N. Am. Bryin. I. 85. 1897. Limnobium montanum (Wils.) Roth. Eur. Laub. 646. 1905. nom. i l l e g . Hygrohypnum eumontanum Crum, Steere & Anderson, Bryologist 68(4):433. 1965. Plants s o f t , i n loosely to t i g h t l y woven patches or mats, either prostrate and t i g h t l y appressed to the substrate or stems and branches somewhat ascending, growing out of ever increasing amounts of accumulating deposits of sand and s i l t . Stems and branches c h a r a c t e r i s t i c a l l y short, rare l y exceeding 2 cm long, usually about 1 cm; branching i r r e g u l a r , the branches often equalling the length of the main stem, but not regularly fastigate. Stems and branches mostly f o l i o s e throughout, denuded only i n very old stems. Color variable, bright or d u l l green, yellow or yellow-green, or dark brown, only the youngest portions of the plants are green or yellow-green, lower or older portions of the stems or branches are dark brown. Stem cross sections revealing 2 to 3 rows of small, thick-walled, brownish or reddish-brown c o r t i c a l c e l l s ; medullary c e l l s larger; t h i n or thick-walled, hyaline or becoming discolored with age; central strand uniformly absent. Rhizoids sparse, a r i s i n g from the base of ventral stem leaves. 364 Leaves variable; closely spaced i n stem or branch a p i c e s , becoming s l i g h t l y more distant below; attitude varying l i t t l e from the wet to the dry condition, but varying greatly with location on the stem; leaves usually ovater-lanceolate, less often lanceolate, variously straight or falcate or squarrose-canaliculate i n the upper h a l f , leaves on the upper side of a prostrate or ascending stem or branch are st r a i g h t , those on the stem or branch flanks are fal c a t e , those on the side nearest the substrate are straight and ovate i n the lower half and squarrose-caniculate above, the o v e r a l l aspect of the leaves i s an erect spreading one, from the apex to the base of a stem or branch the straight dorsal leaves vary more or less continuously from somewhat appressed to erect spreading; upon drying the leaves shrink l a t e r a l l y , the margins often i n r o l l i n g , the entire leaf twisting variously, otherwise the over a l l aspect of spreading to squarrose leaves i s l i t t l e changed from the moist condition; leaves small (0.3) 0.5-0.9 (1.1) mm long X (0.25) 0.3-0.5 (0.9) mm wide; broadly concave i n the lower h a l f , often becoming canaliculate i n the upper half; margins coarsely serrulate over t h e i r entire length or almost en t i r e , often varying among leaves from the same plant, serrulation most conspicuous i n the leaf apex, margins decidedly recurved i n the lower half or plane; leaves occasionally weakly decurrent at the point of i n s e r t i o n ; apex acute to somewhat accuminate; costa slender, usually short and double with one arm reaching mid-leaf, rarely slender and single or short and t r i p l e . Areolation variable; median leaf c e l l s short fusiform to long lin e a r flexuose, rar e l y other than narrow, walls quite thick, varying from (17) 25-50 (69) um long X (3) 4-5 (6) um wide, but varying continously between leaves from in d i v i d u a l plants and not infrequently within one lea f ; leaf c e l l s generally becoming shorter toward the apex, short fusiform to 365 almost rhombic, rarel y some c e l l s i n the apex are papillose by overlapping d i s t a l end walls on the abaxial leaf surface; mostly fewer than 5 such c e l l s per leaf; leaf c e l l s variable toward the leaf base, gradually be-coming shorter and wider, or changing l i t t l e i n length and becoming s l i g h t l y wider i n both cases the walls become more incrassate and i r r e g u l a r -l y p i t t e d ; alar c e l l s variable, undifferentiated or forming a scarcely di f f e r e n t i a t e d group of short rectangular or i r r e g u l a r , incrassate, s l i g h t l y p i t t e d , sometimes yellowish c e l l s . Plants autoicous, Perigonial leaves 0.2-0.5 mm long, broadly ovate, sometimes with a small apiculus or very f i n e l y toothed, rounded apex, c e l l s incrassate, discolored yellow brown, ecostate or f a i n t l y single. Perichae-t i a l leaves radiculose; outer and middle p e r i c h a e t i a l leaves ovate-lanceo-l a t e , squarrose recurved i n the upper half ; inner p e r i c h a e t i a l leaves lanceolate, usually with a long tapering apex, sometimes somewhat squarrose, costa variable, single and slender or very broad and forking 1 to 3 times at i t s terminus, i n either case sending well above midleaf or slender and double reaching midleaf or sometimes absent, plane or very s l i g h t l y p l i c a t e ; margins of a l l p e r i c h a e t i a l leaves coarsely or f i n e l y serrulate i n the apex. Seta 10 to 17 mm long, color yellowish-red to red, smooth, variously twisted when dry, erect or s l i g h t l y arched when wet; capsule t y p i c a l for the genus; annulus of 2 to 3 irreg u l a r rows of c e l l s . Peristome t y p i c a l for the genus; Endostome with 2 to 3 c i l i a between adjacent segments; spores f i n e l y p a p i l l o s e , dusky, 10 to 13 um i n diameter. Hygrohypnum montanum i s a very d i s t i n c t i v e species. The characters that are most useful i n recognizing the species are s l i g h t l y variable and as such are best used i n combination with one another. Useful are the very small, ovate to ovate-lanceolate leaves, the rather prominent serrulation 366 of the l e a f margin (Figs. 76 a-d), the extensive recurvature of the le a f margin i n the lower h a l f of the l e a f (Figs. 75. a-e, h & i ) the absence of a c e n t r a l stand i n the stem and the p e c u l i a r squarrose recurvature of the v e n t r a l stem and branch leaves. Each of these features occur i n d i v i d u a l l y i n other hygrohypnum species, however only i n H. montanum do they come together i n such a unique combination. The s e r r u l a t i o n of the l e a f margin i s extremely u s e f u l i n the recog-n i t i o n of the species. However, the feature should be employed with some c . caution f o r i t does vary somewhat. The margin can be coarsely serrate or almost e n t i r e . I t may be ser r u l a t e only i n the l e a f apex or only i n the upper h a l f of the l e a f , but not i n the apex. The feature can vary among leaves from the same stem. Generally, the s e r r u l a t i o n i s best developed i n the l e a f apex (Figs. 76 a&b). Nyholm (1965) remarked that the le a f apex of H. montanum was s i m i l a r to that of U. molle. Such a s i m i l a r i t y i s at best s u p e r f i c i a l . The l e a f apex of H. molle i s normally blunt and the toothing i s more denticulate, whereas the apex of H_. montanum i s more acute and the toothing i s much sharper. Also, the leaves of H_. montanum are re g u l a r l y f a l c a t e , whereas those of H_. molle never are. L a s t l y , the l e a f margins i n H. montanum are recurved while those of H. molle are plane. The recurvature of the le a f margin i s also u s e f u l i n the recognition of the species, but l i k e the marginal s e r r a t i o n , i t t t o o i s somewhat v a r i a b l e . Most leaves are conspicuously recurved, some are l e s s so and others are v i r t u a l l y plane. P a p i l l a e occur on the p e r i c h a e t i a l leaves of some species, but only i n R. montanum have they ever been observed on vegetative leaves. In a few i s o l a t e d specimens a few c e l l s i n the l e a f apex have exhibited p a p i l l a e created by the ove r r i d i n g , anterior c e l l walls. The occurrence of these p a p i l l a e i s too infrequent to attach any fundamental s i g n i f i c a n c e . ,36.7 The p e c u l i a r c o r r e l a t i o n between leaf a t t i t u d e and p o s i t i o n on the stem should also be noted (Figs. 7 6 f&g). Grout (1931) commented that the stems of H_. montanum were mostly d e f o l i a t e . The observations made during t h i s study do not support t h i s . Grout further noted the presence of "leaf l i k e p a r a p h y l l i a " . I have ob-served pseudoparaphyllia around branch primordia but no p a r a p h y l l i a . Grout (1931) stated that the median l e a f c e l l s were about 5 um wide X 6-10:1. As pointed out e a r l i e r the c e l l s may be both longer and shorter than Grout noted. He also noted that the capsule was c o n s t r i c t e d beneath the mouth when o l d and empty. The capsule may or may not be so c o n s t r i c t e d . Nyholm (1965) observed that the spores of H_. montanum ranged from 14 to 16 um i n diameter. I have found them to vary from 8 to 14 um with most l y i n g between 10 and 12 um. Grout (1931) and Iwatsuki and Naguchi (1974) in d i c a t e that H. montanum occurs i n Japan. I have seen no specimens to support t h i s . Amblystegium montanum Lindb. i s the l e g a l basionym of Hygrohypnum  montanum (Lindb.) Broth. Lindberg (1879) c l e a r l y based h i s name of Hypnum  montanum Wils. i n James (1855), which was i n turn based on the Wilson des-c r i p t i o n of an apparent James c o l l e c t i o n from the White Mtns., New Hampshire. A r t i c l e 64 of the Seattle Code of the rules of nomenclature r e j e c t s the Wilson name as a l a t e r homonym of Hypnum montanum Lam i n B r i d e l (1801). P r i o r to 1879 there was no species of Amblystegium bearing the epithet montanum. I t i s not c l e a r whether Lindberg (1879) made the trans f e r f o r taxonomic or nomenclatural reasons. Regardless, Lindberg was the f i r s t one to transfer the epithet montanum to an acceptable genus. According to A r t i c l e 72 of the Seattle Code the author t r a n s f e r r i n g the epithet of an otherwise i l l e g a l homonym to a su i t a b l e genus should make no reference i n the new combination to the author of the homonym. Therefore, the c i t a t i o n 368 of the Lindberg name should be Amblystegium montanum Lindb. and not A. montanum (Wils.) Lindb. Wijk et a l . (1959) correctly noted t h i s . Broth-erus (1909) cited the i l l e g a l Wilson name as the basionym for his combina-ti o n Hygrohypnum montanum. This also contradicts A r t i c l e 72 of the Seattle Code. Wijk et_ al_ (1962) also noted t h i s and corrected the c i t a t i o n as to refer to Lindberg's A. montanum. Therefore the new name Hygrohypnum eumonta- num Crum, Steere & Anderson, though a commendable attempt to c l a r i f y the sit u a t i o n , i s unnecessary. I t i s evident from the l i t e r a t u r e that neither Wilson, James nor Lind-berg c l e a r l y designated types for t h e i r species. Two specimens are of im-portance i n t h i s regard. At H-SOL there i s a specimen with a handwritten la b e l stating "Hypnum montanum Wils., S.L. exs. n. 453. This specimen i s evidently a fragment of the Sul l i v a n t & Lesquereux Musci Boreali Americani #453. I t seems reasonable to assume that t h i s specimen served as the basis for Lindberg's concept of the species. At NY there i s a specimen also with a hand written l a b e l bearing the data "Hypnum montanum Wils. mss., Mts. A l b i s , N.Y., Dr. James, 1853.^ The c o l l e c t i o n date of the specimen predates the 1855 publication date of the homonym and the specimen was collected by James i n the type l o c a l i t y . Both specimens at H-SOL and NY are c l e a r l y Hygrohypnum montanum. However, the recurvature of the leaf margin of the specimen from H-SOL i s not as well developed as i n the specimen at NY. The James c o l l e c t i o n at NY i s therefore selected as the lectotype for the species. I t does not seem unlikely that the James specimen may well be the o r i g i n a l specimen. 369 Fi g . 75a - i . The habit of the shoot and v a r i a t i o n i n leaf shape of Hygrohypnum montanum. a - e, h, i . Variation i n leaf shape. f, g. The dorsal (f) and ventral (g) views of a t y p i c a l shoot i n the moist condition. Scale: a'-e, h, i; I 0.5mm M f, g; The shoot i s apporoximately 0.5 cm long '370 371 Fi g . 76a - h. C e l l u l a r d e t a i l of the foliage leaves of Hygrohypnum  montanum. a, b. Leaf apices. c, d. Marginal leaf c e l l s . e, g. Median leaf c e l l s . f, h. Alar c e l l s . Scale: a, b, f, h; 1 100um | c - e, g; I ' lOOum I 372 -373 Fig . 77. Hygrohypnum montanum 374 E x s i c c a t i Examined Austin, Musci Appalachiani Supply. I #546 as Hypnum montanum (NY, USA) Bauer, Musci Europaea Exsiccata #1280. (BRNM, NY, DUKE) Grout, North American Musci Pleurocarpi #397 (CANM, MIN, MO, NY, TENN, USA) #485 (MIN, MO, NY, TENN, UC, USA) S u l l i v a n t & Lesquereux, Musci Boreali-Americani Ed. I, #306 as Hypnum montanum. (NY) Ed. I I , #453 as Hypnum montanum. (CANM, NY, NYS) Selected Specimens Examined Canada Quebec Pare du Mont Tremblant, W. of Lac Poisson; Herman 16766. (CANM) New Brunswick Al b e r t Co., Fundy National Park, t r a i l to Laverty F a l l s ; Ireland 11602 (UBC, CANM, DUKE) >. Nova Scotia Cape Breton Island, V i c t o r i a Co., Cape Breton Highlands National Park, Mary Ann F a l l s ; Ireland 10520 (CANM) United States New York Hamilton Co., SE. of Long Lake V i l l a g e , E. of the Gables Cottages; Hermann 14723. (CANM, NYS) Mt. Marcy, Avalanche T r a i l ; E.G. B r i t t o n 2 Sept. 1892.(NY) Massachusetts Mt. Greylack; Andrews 1 Oct. 1908 Vermont Windham Co., along Rd. between Stratton and Ar l i n g t o n , 0.4 mi. E. Windham-Bennington county l i n e ; Jamieson 5284. (UBC) New Hampshire Mt. Washington, o u t l e t of Lake of Clouds; J.A. A l l e n , O.D. A l l e n & A.J. Grout 12 July 1880 as Hygrohypnum  montanum specimen A. i n North American Musci Pleurocarpi #397 (CANM) Norway Ringerike; Bryhn 28 July 1912 i n Musci Europaea E x s i c c a t i #1280 (NY) Sande, Jarlsberg; Kaurin 3 Sept. 1890. (S-PA) Sweden Varmland, Gasborns; Hakelier 23 Oct. 1965. (S-PA) 375 Hygrohypnum c l o s t e r i (Aust.) Grout, Bryologist 13: 14, 1910 Lectotype: Musci Appalachiani #439. 1870. (NY) Hypnum c l o s t e r i Aust., Musci Appalachiani #439. 1870. Amblystegium holzingeri Ren. & Car., Bot. Gaz. 19:240 21c. 1894. Amblystegium c l o s t e r i (Aust.) Card, i n Par., Ind. Bryol. 1:15. 1903. Hypnum malacocladum Card. 8 Ther. Bot. Gaz. 37:380 p i . 25. 1904. Hygrohypnum c l o s t e r i fo. seruulatum Grout, Moss F l . N. Am. 3(2):92. 1931. Plants s o f t , spindly, forming small loosely woven, ea s i l y fragmenting patches. Color d u l l , d i r t y green. Stems prostrate, short, seldom exceed-ing 1 to 1.5 cm i n length, frequently denuded, but for a few clusters of leaves near stem and branch apices:. Branching i r r e g u l a r , branches pros-trate to somewhat ascending, short usually no more than 0.5 cm long. Stems and branches regularly radiculose from the bases of ventral leaves, rhizoids red, smooth walled. Stem cross sections revealing 2 to 3 rows of small, thick walled, brownish c o r t i c a l c e l l s which enclose larger, thinner walled medullary c e l l s , medullary c e l l s usually hyaline, but frequently becoming discolored with age; central strand present, well developed. Leaves generally narrowly ovate or lanceolate, though not infrequent-l y ovate lanceolate or ovate; leaf apex acute, but blunt; leaves uniformly straight; (0.3) 0.6-0.9 (1.75) mm long X (0.2) 0.3-0.4 (0.75) mm wide; leaves plane or rare l y weakly concave; margins entire and plane; costa usually single reaching 1/2 to 3/4 of the leaf length, much less frequently short and double or single and forked, variously slender or stout; leaves varying i n attitude from the wet to the dry condition, when wet the leaves 376 are loosely patent, when dry they are very wide to crest spreading, shrunken markedly with the margins often somewhat i n r o l l e d , the leaves variously twisted. Areolation variable; median leaf c e l l s fusiform or rhombic, st r a i g h t or fleuose, sometimes line a r flexuose, varying from (23) 30-50 (63) um long X (4) 6-7 (13) um wide, generally varying continuously, the very widest c e l l s occurring only i n the largest stem leaves; a p i c a l leaf c e l l s becoming shorter, d i f f e r i n g l i t t l e i n shape; basal leaf c e l l s variable, becoming shorter, longer or wider or changing l i t t l e ; alar c e l l s variable, usually l i t t l e d i f f e r e n t from adjacent basal c e l l s , or as a few gradually widened, quadrate or rectangular c e l l s , generally exhibiting no color d i f f e r -e n t i a t i o n with age. Plants autoicous; perigonia and perichaetia occurring i n d i v i d u a l l y or i n uni- or bisexual p a i r s , conspicuously radiculose from the base; perigonia ovate; outer perigonial leaves small transverse ovate from a truncate base, ecostate, margins entire; inner periogonial leaves ovate with a s l i g h t l y tapering apex, exostate, margins e n t i r e , deeply concave imbricate; outer p e r i c h a e t i a l leaves triangular, sometimes s l i g h t l y reflexed at the t i p , margins entire and plane; inner p e r i c h a e t i a l leaves triangular lanceolate, reaching 1.5 to 2.0 mm long, straight erect, plane not p l i c a t e , a l l p e r i c h a e t i a l leaves strongly single costate. Seta erect to s l i g h t l y arched, 7-10 (20) mm long, yellowish or yellowish-red, smooth, s l i g h t l y twisted when dry; capsule t y p i c a l for the genus; operculum conic with a small terminal papillum, r a r e l y becoming s l i g h t l y rostrate. Peristome t y p i c a l for the genus; annulus deciduous, of one to two rows of c e l l s ; inner peristome with 1 to 3 wel l developed c i l i a between adjacent segments; spores dusky yellow, f i n e l y papallose, (12) 13-17 (20) 377 um i n diameter. This small, incompletely understood, but distinctive species, may be easily recognized by the small, spindly growth habit, the usually small, lanceolate leaves with their acute, but flunt apices and the strong, single costa reaching 1/2 to 3/4 of the leaf length (Fig. 78'a,b,e-g). Particularly unusual i s the very distant leaf spacking coupled with the spreading nature of the leaves. (Figs. 78 c&d). Certain infraspecific variation seems to correlate with geography. Throughout the species' range the seta length varies from 7 to 20 mm. The seta length of specimens from New England, New Jersey, New York, and Pennsyl-vania i s generally shorter, in the range of 7 to 11 mm. Only a single f e r t i l e specimen i s known from the southern range limits in North Carolina. In that specimen the seta length varies from 16 to 20 mm. It has also been observed that the median leaf cells of specimens from North Carolina are on the average slightly longer than those of northern specimens. However, i t must be noted that these apparent discontinuities may well be artifacts of collec-tion for there are only 12 known lo c a l i t i e s for the species and scarcely 50 specimens. These are far too few specimens from which to draw r i g i d generali-zation. In general, there i s no appreciable difference in the size of stem>and branch leaves. Occasionally the stem leaves in some of the more vigorous specimens may reach nearly twice the length of branch leaves, in the range of 1.5 to 1.8 mm long. The costa of these long leaves may frequently assume a reddish color. Grout (1931) described Hygrohypnum closteri fo. serrulata based on the apparent presence of a serrulate leaf marign. The holotype and the only 378 known specimen of the form was collected i n 1898 by Burnett from Bolivar Run, Pennsylvania, Examination of the holotype from DUKE reveals not the s l i g h t e s t suggestion of marginal toothing i n the leaves. No appreciable difference between the alleged form and other specimens of the species could be discerned. I t i s concluded that the form does not warrant taxonomic recognition. Renauld and Cardot (1894) described Amblystegium holzingeri on the basis of a Holzinger c o l l e c t i o n from Rock Creek on the banks of the Potomac River near Washington D.C. The holotype of t h i s species has not been available for study. However, careful study of the type description and the excellent i l l u s t r a t i o n c l e a r l y show that the Renauld taxa i s the same as Hygrohypnum c l o s t e r i . For want of adequate c o l l e c t i n g data i n the type description Grout (1931) excluded Hypnum malacocladum Card. & Ther. from his treatment of Hygrohypnum. The type description c i t e s a single specimen i n the Debat herbarium as the holotype. Examination of the i l l u s t r a t i o n accompanying the type description and a specimen from the Debat herbarium, now at S-PA, indicates that Hypnum malacocladon i s i d e n t i c a l to Hygrohypnum c l o s t e r i . The po s i t i o n of Hygrohypnum c l o s t e r i i n the genus i s unclear. The lanceolate to narrowly ovate leaves with the i r t y p i c a l l y strong, single costa would seem to a l l y H_. c l o s t e r i with H. luridum and more remotely with H. polare. However, the absence of any appreciable alar d i f f e r e n t i a t i o n i s H. c l o s t e r i reduces the l i k e l i h o o d of a r e a l a f f i n i t y between H. c l o s t e r i and H_. luridum and/or H. polare. The leaves of H_. c l o s t e r i regularly are spaced d i s t a n t l y along the stem and are spreading. Elongated internodes usually are associated with specimens having grown under less than optimum conditions, whereas i n H. c l o s t e r i the condition appears to 379 be the norm. Further, spreading leaves often occur i n other species throughout the genus, but the spreading leaf attitude i s one of a variety of leaf attitude that might be exhibited. In Hygrohypnum c l o s t e r i the normal condition i s one of spreading leaves. The absence of any appreciable leaf concavity also i s o l a t e s the species, for the species comprising the central core of the genus exhibit conspicuous concavity. The t y p i c a l concavity found within the genus i n conjunction with shorter internodes imparts a loosely imbricate to jucaceous appearance to the stems. This feature i s c l e a r l y absent i n H_. c l o s t e r i . The l i n e a r dimensions of the median leaf c e l l s of H_. c l o s t e r i l i e w e l l within the l i m i t s for the character i n most other species i n the genus. However, the general impression one receives from the areolation i s that of Amblystegium. The blunt, though acute leaf apex of Hygrohypnum c l o s t e r i i s unlike the more pointed leaf apices frequent among the a l l i e s of H_. luridum. Blunt or obtuse leaf apices are frequent i n the genus, but only among those species with much wider leaves than those of H_. c l o s t e r i . The inner p e r i c h a e t i a l leaves of H_. c l o s t e r i are straight and strongly single costate. Although they are shallowly concave, they do not exhibit the conspicuous p l i c a e evident i n the inner p e r i c h a e t i a l leaves of most other Hygrohypna. The habitually straight leaves of H. c l o s t e r i are unusual among H_. luridum and i t s a l l i e s for t h e i r leaves are usually falcate or straight. In 1870 Austin issued Hypnum c l o s t e r i as Musci Appalachiani #439. Grout (1931) designated t h i s exsiccata as the lectotype. In neither case did Austin or Grout select a single specimen as the type. As a r e s u l t of t h i s study a single specimen of t h i s exsiccata from NY has been appropriately designated as the lectotype. The specimen requires some comment. The 380 specimen consists of two fragments. One fragment c l e a r l y shows the d i s t a n t erect spreading leaves of the dry p l a n t s . The second fragment i s somewhat troublesome f o r there i s some v a r i a t i o n i n l e a f shape. Certain leaves are unusually ovate f o r the species and though the leaves are widely spaced they are rather appressed. As a consequence the fragment looks, i n p a r t , super-f i c i a l l y l i k e a spindly specimen of Hygrohypnum molle. However, the areo-l a t i o n , the shape of the l e a f apex and the e n t i r e l e a f margins c l e a r l y show i t to be Hygrohypnum c l o s t e r i , p a r t i c u l a r l y when such parts are contiguous with p e r f e c t l y normal appearing H. c l o s t e r i . Grout (1903) also noted the s u p e r f i c i a l s i m i l a r i t y with H. molle. 381 Fi g . 78a - g. The habit of the shoot and the va r i a t i o n i n leaf shape of Hygrohypnum c l o s t e r i . a, b, e - g. Variation i n leaf shape, c, d. A shoot i n the moist (d) and dry (c) condition. Scale: a, b, e - g; i 0.5mm 1 c, d; The shoot i s approximately 0.5 cm long 382 383 Fig. 79a - g. C e l l u l a r d e t a i l of the foliage leaves of Hygrohypnum  c l o s t e r i . a, b. Leaf apices. c, d. Median leaf c e l l s . e. Marginal leaf c e l l s . f, g. 'Alar'cells. 385 Fig . 80. Hygrohypnum c l o s t e r i 386 E x s i c c a t i Examined Austin, Musci Appalachiani #439 as Hypnum c l o s t e r i . (NY, UBC, USA) Selected Specimens Examined United States North Carolina Polk Co., Green River Gorge; Zander 3049 (DUKE) Swain Co., Great Smokey Mountain National Park, Kanati Fork, Newfound Gap; Schofield 8883 as Hygrohypnum  co c l e a r i f o l i u m . (DUKE) McDowell Co., L i n v i l l e River, Along North Fork River; Anderson & Felton 9568 as Leptodictyum riparium, (DUKE) D i s t r i c t of Columbia Rock Creek; Holzinger 11 June 1891 as Amblystegium  h o l i z i n g e r i Ren. S Card. (MIN) New Jersey Closter; Austin as Hypnum c l o s t e r i i n Musci Appalachiani #439. (NY-Lectotype, UBC, USA) Palisades; Austin 19 Sept. 1866 as Hypnum obtusifolium nom. nud. i n sched. (NY) New York Sam's Point; Austin Aug. 1867. (N) Palisades; Austin 15 July 1865 as Hypnum dimorphum B r i d . (NY) Nangles Brook ( s p e l l i n g ? ) ; Austin May, June 1872 as Hypnum c l o s t e r i . (NY) Pennsylvania Bol i v a r Run; Burnett 7 July 1897 as Hypnum c l o s t e r i . (NY) McKean Co., Boliv a r Run; Burnett 11 Sept. 1898 as Hypnum c l o s t e r i f . serrulatum. (DUKE-Holotype) Vermont Newfane; Grout 13 July 1900. (DUKE) Maine North Bridgeton; Wilson 14 July 1908 as Hypnum c l o s t e r i . (NY) 387 EXCLUDED SPECIES AND SPECIES OF QUESTIONABLE AFFINITIES Hygrohypnum aureum Herz., Biblioth. Bot. 87:145. 67. 1916. Careful examination of several isotypes (BM, H, JE, S-PA) indicates that the species i s best treated as Scorpidium turgescens (Th. Jens.) Loesk. Scorpidium turgescens and the Herzog plant agree in virtua l l y a l l c r i t i c a l characters; the yellow or rusty-yellow color, the ovate-oblong or broadly ovate leaves, which frequently exceed 3 mm in length, the leaf concavity, the irregular to quadrate or short rectangular, incrassate alar c e l l s , the short, double costa and the concave to cucullate apex bearing an abruptly differentiated, hooked apiculus. Hygrohypnum brasiliense Herz., Hedwigia 67:258. 1927. (Holotype at JE) The holotype and only known specimen of this species superficially resembles Hygrohypnum alpestre. The deeply concave, oblong leaves of both species are of nearly the same size (2.1 mm X 1.0 i n H. brasiliense versus 0.9 to 1.9 mm X 0.4 to 1.0 i n H. alpestre). Also similar are the leaf apices with their minutely reflexed apiculi. The abruptly inflated alar cells and the peculiar metallic green sheen of H. brasiliense are similar to H. eugryium. At the same time the metallic sheen i s very similar to the sheen observed i n the leaves of some species of Sematophyllum. Scrutiny of the hyaline alar^cells reveals the presence of an enlarged basal row of 4 to 5 rectangular to crescentic cells which are of regular occurrence throughout the Sematophyllaceae. The very weak, short, double costa and the absence of a central strand i n the stem cross-section are also features of the Sematophyllaceae. The plane, ovate-oblong inner perichaetial leaves are unlike the typically plicate perichaetial leaves of other Hygrohypna. 3 8 8 On the basis of the metallic sheen i n the leaves, the nature of the costa and alar c e l l s and the absence of a central strand i n the stem, i t i s suggested that the r e a l a f f i n i t i e s of Herzog's peculiar plant reside with the Sematophyllaceae. Hygrohypnum caussequei Ren, et Card., B u l l . Soc. R. Bot. Belg. 35(1): 325. 1897. (Holotype at PC) This plant does not belong to the genus Hygrohypnum. The plant exhibits a combination of characters that are unlike any recognized species of Hygrohypnum. The narrowly lanceolate leaves, which taper gradually into a sharply acute point, are minutely serrulate. The leaf i s attached to the stem across a truncate i n s e r t i o n l i n e . There i s none of the abrupt tapering of the leaf base at i t s insertion that i s so common i n Hygrohypnum. The leaf angles exhibit no alar d i f f e r e n t i a t i o n at a l l . The stem" cross sections reveal that a central strand i s absent and that the thick-walled medullary c e l l s are surrounded by only two layers of small thick walled c o r t i c a l c e l l s . The relationships of t h i s enigmatic l i t t l e plant have yet to be established. Hygrohypnum circinatum Herz. Mem. Soc. F. F l . Fern. 25:51-53. 5a-h. 1950. Examination of the holotype and the only known specimen of th i s Herzog species reveals that i t does not belong to Hygrohypnum. The holotype i s at JE. For a detailed discussion of th i s species see the discussion of Hygrohypnum pelichuense. Hygrohypnum coreanum Card., B u l l . Soc. Bot. Gen. Series 2,4:322. 1912, Neither the type nor any other specimen of t h i s species has been available for study. Comments accompanying the type description render 389 some room for speculation as to the r e a l nature of the taxon. The broadly ovate to suborbicular leaf shape with the broadly obtuse apex suggests either H. s m i t h i i or H. duriusculum. I f the apical c e l l s are, i n f a c t , ovate, then there i s a d i s t i n c t resemblance to H. s m i t h i i . That the costa i s always short and double i s more l i k e H. duriusculum. The lax, sub-quadrate to oblong alar c e l l s suggest some poorer forms of H. duriusculum as the alar c e l l s of H. s m i t h i i are always rather incrassate. The evaluation of the species w i l l have to await, the a v a i l a b i l i t y of the holotype. Hygrohypnum d o i i Sak. Bot. Mag. Tokyo 46:379. 1932. ~(holotypes at MAK) This Sakurai species and i t s variety simplex must be excluded from Hygrohypnum. Examination of the holotypes of both taxa reveal the presence of well developed p a p i l l a e on the abaxial surfaces of the leaves. These papilla e are formed by overlapping anterior end walls. Although such pa p i l l a e occur on the p e r i c h a e t i a l leaves of Hygrohypnum alpinum and H. molle, they are otherwise unknown i n the genus. Perhaps the a f f i n i t i e s of t h i s plant reside with the Sematophyllaceae. Hygrohypnum e l l i p t i c u m Ther., Rev. Bryol. ((1&2): 32-33. f.17. 1936. (Holotype at S-PA) Therio.t (1936) suggested a relationship between his species and Hygrohypnum s m i t h i i . I t i s true that both plants exhibit a strong single costa and an obtuse or rounded leaf apex. Further, the e l l i p t i c a l leaf shape noted by Theriot i s not too d i s s i m i l a r from the broadly ovate or orbicular leaf shape of H_. s m i t h i i . However, the rectangular shape of the median leaf c e l l s , c l e a r l y i l l u s t r a t e d i n his paper and v i s i b l e i n the plants, i n spite of a heavy incrustation of diatoms, i s fundamentally d i f f e r e n t from the rhombic to l i n e a r flexuose areolation of Hygrohypnum. 390 On this basis, the Theriot plant must be excluded from Hygrohypnum. The true relationships of t h i s taxon are unclear. A number of features seem to indicate a f f i n i t i e s with the Bryaceae. I t i s not en t i r e l y clear that Theriot's plant i s a pleurocarpous moss. Most of the leafy axes are unbranched, varying from 1 to 3.5 cm long. A few exhibit one or two broken, i r r e g u l a r l y placed branches near the base of the stems. Were i t not for the fact that those branches arise at an angle of 90° from the stem, one might interpret them as innovations of an acrocarpous moss. The widely spaced leaves seem to suggest growth under highly humid conditions. Curiously, the younger parts of the stem and the costae of younger leaves are reddish. Though obtuse, the leaves seem to resemble the Bryaceae. The margins are strongly recurved and the leaf base i s conspicously decurrent. Were the leaf apex acute or acuminate the s i m i l a r i t y with the Bryaceae would be a l l the more s t r i k i n g . An effective assessment of t h i s plant must await the discovery of f e r t i l e material. Hygrohypnum entodontoides Broth, et Par., B u l l . Herb. Boiss, ser. 2, 2:989. 1907. (Holotype at H-BR, isotype at PC) I f t h i s plant was known only