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Hyphomycetes from sediments of Marion Lake, British Columbia Chang, Yola Chiou-Yueh 1975

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HYPHOMYCETES FROM SEDIMENTS OF MARION LAKE, BRITISH COLUMBIA by YOLA CHIOU-YUEH CHANG B.Sc, National Taiwan U n i v e r s i t y A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY in the Department of Botany We accept t h i s thesis as conforming to the THE UNIVERSITY OF BRITISH COLUMBIA February, 1975 In presenting th i s thes is in par t i a l fu l f i lment of the requirements for an advanced degree at the Univers i ty of B r i t i s h Columbia, I agree that the L ibrary sha l l make it f ree ly ava i lab le for reference and study. I fur ther agree that permission for extensive copying of th i s thes is for scho lar ly purposes may be granted by the Head of my Department or by his representat ives. It is understood that copying or pub l i ca t ion of th i s thesis f o r f inanc ia l gain sha l l not be allowed without my wr i t ten permission. Depa rtment The Univers i ty of B r i t i s h Columbia Vancouver 8, Canada D ate 7 9 A a ) / i i ABSTRACT Geofungi, mainly Hyphomycetes, are important members of aerobic aquatic habitats. The occurrence, distribution and seasonal v a r i -ation of Hyphomycetes in Marion Lake sediments were studied, using a modi-, fied dilution plate method. The maximum number of viable fungi occurred during the winter. The highest fungal count as well as the largest number of fungal species was found in the deeper-water muds. The pattern of spatial and seasonal variations of fungi i s interpreted as the result of . the combined action of many factors, such as, temperature, pH and organic matter content of the muds, r a i n - f a l l and other microorganisms, a l l of which affected the pattern to different degrees and at different times. This study shows that there is a sizable and diverse population of Hyphomycetes in Marion Lake sediments. Seventy-three species and species groups, excluding Penicillium species, belonging to 39 genera were isolated and identified. ' The taxonomy, morphology, ecology and physiology of some of these Hyphomycetes are briefly reviewed. (?)Humicola sp., Penicillium, Trichoderma and hyaline and dark Mycelia S t e r i l i a were the most common fungi. As determined by the agar-diffusion method, 32 of the 36 species and varieties of Hyphomycetes tested exhibited cellulolyfcic ability-. Trichoderma was the strongest cellulose decomposer. Fungal activity in situ also was investigated, being based on observations of cellophane decomposition in the lake muds. In the process of cellophane breakdown, as determined by direct microscopy, cultural isolation and scanning electron microscopy, there was an indication that fungi are more important decomposers than either b a c t e r i a or actinomycetes The Hyphomycetes i s o l a t e d from buried cellophane were the same species recorded as dominant fungi when the modified d i l u t i o n p l a t e method was use fo r i s o l a t i o n . Thus, i t i s implied that these Hyphomycetes are s i g n i f i -cantly responsible f o r the decomposition of c e l l u l o s e i n Marion Lake muds. iv TABLE OF CONTENTS Page PART I Occurrence, Distribution and Seasonal Variations of Hyphomycetes from Marion Lake Sediments . . . 1 Introduction 1 Materials and Methods 7 Study Area 7 Sediment Sampling 7 Isolation: Modified Dilution Plate Method 10 Dry Weight and St a t i s t i c a l Expression 12 Organic Matter Content 13 Temperature and pH 13 Comparison of Incubation Temperatures 13 Identification of Fungi 13 Results 15 Annotated List of Hyphomycetes from Marion Lake sediments . . 15 Environmental Factors 76 Organic Matter 76 pH 76 Temperature 82 Isolation Medium 82 Comparison of Incubation Temperatures: 5°C and 25°C for Isolation of Fungi 85 Seasonal and Spatial Variations 87 Seasonal Variation 87 Spatial Occurrence and Distribution 110 Discussion 123 PART II Cellulolytic Ability of Fungi Isolated from Marion Lake Sediments as Determined by the Agar-Diffusion Method . . . . 136 Introduction 136 Materials and Methods 138 Preparation of Acid-Swollen Cellulose in Cold Room at 4°C . . 138 Assay Medium 138 Stat i s t i c a l Test 139 V TABLE OF CONTENTS —Continued Page Results and Discussion 140 PART I I I Preliminary Study of Fungal A c t i v i t y i n s i t u Based on the Observation of Decomposition of Buried Cellophane i n Marion Lake Muds 151 Hughes-Chang Sampling Column and Technique 151 Microscopical Examination 152 I s o l a t i o n of Microorganisms on Buried Cellophane Films 154 Scanning Electron Microscopy . 156 Conclusion 156 LITERATURE CITED 159 APPENDICES 177 v i LIST OF TABLES Table Page I. Sediment characteristics and numbers of fungi per gram of dry sediment at each of six Marion Lake sampling stations, June, 1970, to April, 1971 77 II. Fungi and their numbers of isolates on Czapek solution agar and/or 2% malt agar isolated from Marion Lake sediments • • 83 III. Numbers of isolates recorded at 5°C (6 weeks) and 25 C (6 days) from Marion Lake sediments, Station 3 . . . . 86 IV. Seasonal distribution of Hyphomycetes from Marion Lake sediments 93 V. Spatial distribution of Hyphomycetes from . Marion Lake sediments . I l l VI. A summary of the numbers of isolates, species and species groups of Hyphomycetes recorded from Marion Lake sediments 114 VII. Spatial and seasonal distribution of Hyphomycetes isolated from Marion Lake sediments 119 VIII. Depth of clearing of acid-swollen cellulose column by Hyphomycetes from Marion Lake sediments 143 IX. Depth of clearing of acid-swollen cellulose column by Hyphomycetes from Marion Lake sediments at 5°C, 15°C and 25°C 148 X. Microorganisms isolated from buried cellophane films plated on Czapek solution agar, 2% malt agar and potato dextrose agar, April, to October, 1972 155 v i i LIST OF ILLUSTRATIONS Figure Page 1. Marion Lake, showing depth contours in meters and location of the 6 sampling stations used in this study . . 9 2. Seasonal variation in organic matter content(%), Marion Lake surface sediments (Section I) 79 3. Seasonal variation in organic matter content(%), Marion Lake lower sediments (Section II) 81 4. Seasonal variation of viable fungal propagules per gram of dry surface sediment (Section I) from Marion Lake stations (log scale) and mean number of species and species groups per station 89 5. Seasonal variation of viable fungal propagules per gram of dry lower sediment (Section II) from Marion Lake stations (log scale) 91 6-11. Seasonal variation - number of isolates from Marion Lake sediments 97-107 12. Seasonal variation - percentage absolute density of the seven most common Hyphomycetes from Marion Lake sediments 109 13. Percentage absolute station density of more common Hyphomycetes from Marion Lake sediments 116 Plate I 21 II 27 III 34 IV 49 V 51 VI 57 VII . 66 VIII 71 v i i i LIST OF ILLUSTRATIONS —Continued Plate Page IX 74 X 147 XI 150 ix LIST OF APPENDICES Appendix Page I. Organic matter(%), pH and temperature of Marion Lake sediments and numbers of viable propagules per gram of dry sediment 178 II. Species name and number 181 III. Computer printout of seasonal distribution, absolute season densities and actual numbers of isolates (in parentheses) of fungi isolated from Marion Lake sediments 183 IV. Computer printout of spatial distribution, absolute station densities and actual numbers of isolates (in parentheses) of fungi isolated from Marion Lake sediments 184 X ACKNOWLEDGMENTS I am h e a r t i l y g r a t e f u l to my supervisor, Dr. G i l b e r t C. Hughes for h i s d i r e c t i o n , advice and encouragement throughout t h i s study and for his patient and c r i t i c a l reading of t h i s manuscript. I am much indebted to the members of my research committee, Dr. R. J . Bandoni, J. R. Stein, W. B. Schofield and R. F. Scagel f o r o f f e r i n g h e l p f u l suggestions during the committee meetings, f o r making the f a c i l i t i e s of t h e i r l a b o r a t o r i e s a v a i l a b l e and for reviewing t h i s t h e s i s . I am also much obliged to Dr. K. Pirozynski, Ottawa and Dr. C. J . K. Wang, New York f o r t h e i r assistance i n i d e n t i f i c a t i o n of some troublesome fungi i s o l a t e d during t h i s i n v e s t i g a t i o n and Dr. T. Booth, Univ e r s i t y of Manitoba f o r i d e n t i f i c a t i o n of ch y t r i d s . Special thanks are due to Mr. K. Tsumura, Department of Zoology, UBC and Mr. Gordon Neish, Department of Botany, UBC for t h e i r f i e l d assistance; Mr. M. T. Higham, Department of Botany, UBC for h i s operation of Scanning Electron Microscope; Mrs. Lauriente f o r her computer program-ming and Mrs. C l a r i c e H a i l l e y f o r her patience i n typing t h i s manuscript. F i n a l l y , my thanks are due to the National Research Council of Canada for f i n a n c i a l support. 1 PART I OCCURRENCE, DISTRIBUTION AND SEASONAL VARIATIONS OF HYPHOMYCETES FROM MARION LAKE SEDIMENTS INTRODUCTION Since the f i r s t isolation of fungi from s o i l by Adametz in 1886, numerous studies on s o i l fungi have been carried out throughout the world. Of a l l the compilations concerning s o i l fungi, Gilman's Manual (1957) is the most comprehensive. In this manual, Gilman supplied not only the des-criptions of the representative fungi isolated from s o i l and keys for iden-tifying them but also brought together the distributional information from Europe, North America, Australia, Asia, Egypt, Brazil and Russia, up to 1956. His bibliography also indicates most of the earlier works dealing with taxonomic and morphologic aspects. Just as in other fields of study, i t is only after this fundamental information is accumulated that investi-gators begin to take ecological problems into consideration. The most eminent ecological studies are those of Warcup (1951), Sewell (1959a), Dick and Newby (1961), Dick (1963), Williams and Parkinson (1964), Balassoriya and Parkinson (1967) and Parkinson and Balassoriya (1967, 1969) in England; Saksena (1955), Mishra (1965, 1966a, 1966b), Dayal and Gupta (1967) and Mehrotra and Kakkar (1972) in India; Borut (1960) in Israel; Tresner et a l . (1954), Miller et a l . (1957), Christensen et a l . (1962) and Gochenaur and Whittingham (1967) in United States; Chou and Stephen (1968) in Hong Kong. Garrett (1951) attempted to classify s o i l fungi into five ecologi-cal groups, on the basis of substrate relationships, viz., saprophytic sugar fungi, root-inhabiting fungi, lignin-decomposing fungi, coprophilous fungi and predaceous fungi. Recently, Domsch and Gams (1972) published an 2 extensive account of agricultural s o i l fungi. The existing data on the ecology and physiology of a number of selected fungi were gathered most comprehensively in their work. The pioneer work on Canadian s o i l fungi was conducted by Bisby et a l . (1933, 1935) and Timonin (1935) in cultivated and forest soils of Manitoba. They concluded that the surface horizons had the greatest total numbers of organisms; certain species of fungi might be characteristic of certain types or horizons of s o i l ; and s o i l temperature and moisture played a part in the fluctuations of fungal numbers in the s o i l . In studying the distribution of microorganisms in Quebec s o i l , Gray and Taylor (1935) showed that the biological activity was dependent upon the organic-matter of the horizons. A comprehensive l i s t i n g of s o i l fungi from Saskatchewan and Manitoba was published subsequently by Bisby (1938), a l i s t that was supplemented recently by Sutton (1973). The mycoflora of Ontario cedar forest soils was investigated extensively by Bhatt (1965, 1970). He observed a quantitative and qualitative decrease in s o i l fungi with increase in s o i l depth and higher fungal counts in the winter than at any other season. There are, of course, several individual taxonomic treat-ments of Canadian s o i l fungi. The most notable is that of Barron (1968), concerning the s o i l Hyphomycetes. Up to the present, knowledge of s o i l fungi in British Columbia is scanty although marine fungi have been inves-tigated by Hughes (1969) and Booth (1969). As noted by Sparrow (1968), "... the ecology of freshwater fungi has not attained the degree of prominence and sophistication reached, for example, by the ecology of s o i l fungi". Moreover, most studies of lake microbiology have concentrated on bacteria, actinomycetes, and yeasts (Henrici, 1939; Umbreit and McCoy, 1941; Waksman, 1941; Taylor, 1948; 3. Hedrick and Soyugenc, 1967; Hedrlck et a l . , 1968; Harrison et a l . , 1971). Aquatic Phycomycetes have been studied also by a number of workers, notably Willoughby (1961a, 1961b, 1962, 1965), Collins and Willoughby (1962), Roberts (1963), Willoughby and Collins (1966) and Dick (1966) in English lakes; Suzuki (1960a, 1960b, 1961a, 1961b) in Japanese lakes; Paterson (1967) and Sparrow (1968) in Michigan lakes; and Rooney and McKnight (1972) in L i l y Lake, Utah. These studies concluded that: (a) marginal zones of lakes have richer and more diverse chytrid populations than the f i e l d above or the permanently submerged muds below; (b) the unit volume viable spore content of the lake surface mud is often much higher than that of the water above; (c) Saprolegniales are not recorded commonly from muds by plating methods, indicating that surface mud is not a major reservoir for these fungi; (d) seasonal changes in the distribution of aquatic Phycomycetes, particularly oomycetous fungi, can be detected but patterns differ with the type of lake; (e) the distribution of aquatic fungi shows a close correlation with the amount of dissolved oxygen in the water; (f) aquatic Phycomycetes are more abundant in neutral lakes than in acidic lakes; and (g) presence or absence of natural substrata, such as l i l y pads or algae, might account for the presence or absence of some species of aquatic Phycomycetes at certain periods. Since Ingold's study on aquatic Hyphomycetes in 1942, considerable attention has been devoted to this group of fungi, e.g., Ingold (1949, 1956, 1958) in Switzerland, Nigeria, Uganda and Rhodesia; Nilsson (1958, 1962, 1964) in Sweden; Suzuki and Nimura (1960) and Tubaki (1957, 1958, 1960) in Japan; Ranzoni (1953), Hudson and Ingold (1960), Ingold (1960), Petersen (1962, 1963a, 1963b) and Anastasiou (1964) in North America. In a l l of the above mentioned works, i t is obvious that 4 Phycomycetes, either parasites or saprobes, and aquatic Hyphomycetes have attracted the greatest attention in studies of fresh water mycobiota. However, Cooke (1961) stressed that "... certain more prosaic types of fungi also occur in the aquatic habitat". Based on the habitat, Cooke grouped the fungi in freshwater into "hydrofungi", those species whose l i f e cycle i s adjusted to be completed in water, including water present only as a film sufficiently thick to permit the swimming of the zoo-spores or gametes; and "geofungi", those species familiarly known as the s o i l fungi, which are not especially adapted to an aquatic existence but whose l i f e cycle may be completed under water because of an adequate supply of nutrients. Subsequently, Cooke (1961) demonstrated a vast number of geofungi (approximately 128 species) isolated from water and sediments of Lytle Creek, Cincinnati. Recently, Park (1972) in the study of fungi in organic detritus in freshwater of Northern Ireland also isolated a high number of fungi which are recognized usually as s o i l fungi and are con-sidered as more closely associated with decomposing organic matter in terrestrial environments, for example, Mucor hiemalis Wehmer, Cephalosporium spp., Trichoderma koningii Oud., Fusarium spp., Gliomastix  murorum (Corda) Hughes var. felina (Marchal) Hughes, Trichocladium opacum (Corda) Hughes and Penicillium spp.. Thus, i t has been suggested that these geofungi, mostly Hyphomycetes are permanent members of the aerobic aquatic population and that they may have biological significance in relation to the decomposition of organic materials in this environment (Cooke, 1961; Kaushik and Hynes, 1971 and Park, 1972). Sparrow (1968) also noted that bottoms of lakes support a limited but diversified fungous flora, primarily of chytrids and Fungi Imperfeeti. As compared to the studies of chytrids, only three attempts (Potter and 5 Baker, 1956, 1961 and Sugiyama eit a l . , 1967) have been made to investigate Fungi Imperfect! in this habitat. Potter and Baker's microbiological study of Montana lakes indicated: (a) there is a persistent fungus popu-lation in the lake bottom muds; (b) inlet areas have the highest microbial counts; (c) fungal counts and the number of species of the bottom muds are in excess of that of the water; and (d) species of Penicillium and Fusarium, Geotrichum candidum Link ex Persoon, Cladosporium hordei (Bruhne) Link ex Gray (syn. Hormodendron hordei Bruhne) and Cladosporium  herbarum (Pers.) Link ex Gray are common in the lake bottom muds. Sugiyama jst al_. (1967) studied the mycoflora of ice-free Vanda Lake, Antarctica and concluded: (a) there is a gradual increase in the number of fungi from lake-water to lake bottom sediments (in agreement with the findings of Potter and Baker, 1956, 1961); (b) more numerous fungal strains are isolated from the bottom sediments of the lake when incubated at 25°C than at 10°C; and (c) species of Aspergillus, Penicillium and Trichoderma are predominant. Collins and Willoughby (1962) also reported the isolation of Cladosporium herbarum, Mucor sp., and Penicillium sp. from the surface muds of Blelham Tarn, England. No detailed qualitative or quantitative analyses were made by any of these investigators. Marion Lake (or Jacobs Lake), British Columbia was selected by the Canadian International Biological Programme for extensive ecological study, the main objective being to determine energy flow in such an aquatic ecosystem (Efford, 1970). An ecological study of the Saprolegniaceae in Marion Lake was carried out by Dick (1970, 1971) but other fungi have not been studied there previously. Dick concluded that (a) most Saprolegniaceae are primarily restricted to the emergent l i t t o r a l and l e n t i c / l i t t o r a l interface; (b) species of Saprolegniaceae associated with insect exuviae 6 are more obviously involved i n the energy flow than others since there may be an energy transfer from c h i t i n , protein, l i p i d and/or moulting f l u i d s glucan polymers (oomycete wall material) and plant l i p i d s (oomycete protoplasmic reserve globules); and (c) there are d i f f e r e n t pathways i n the contribution to the energy flow of the lake ecosystem by fungi, f o r example, d i r e c t conversion of energy v i a fungus feeders or omnivores; and d i r e c t or i n d i r e c t conversion of energy v i a plants, b a c t e r i a or d e t r i t u s feeders. The present study was designed with the following objectives: (a) to provide general information on the d i s t r i b u t i o n and occurrence of fungi i n Marion Lake sediments, with p a r t i c u l a r emphasis on Hyphomycetes; (b) to determine the seasonal v a r i a t i o n of these fungi through bimonthly c o l l e c t i o n s ; (c) to assess the extent of c o r r e l a t i o n between fungus occurrence and d i s t r i b u t i o n and the seasonal changes i n environmental parameters- pH, temperature and organic matter content of the muds; and (d) to provide data which might serve as a basis f o r subsequent studies on the r o l e of sediment fungi i n a lake ecosystem. 7 MATERIALS AND METHODS STUDY AREA Marion Lake (49°18'30"N, 122°32'48"W) is located in the granitic coastal mountains in southwestern British Columbia, 50 km east of Vancouver, and 10 km north-northeast of Haney. It is a small shallow lake, approximately 13.33 ha in area, about 800 m long and 200 m across at the widest point. The mean depth is approximately 2.4m, and the maximum depth is 7 m. The lake bottom is covered by deep silt-ooze except near the inlet and the outlet, where sand and gravel are exposed. Efford (1967) and Mathews (1973.) have presented more detailed descriptions of Marion Lake and i t s geological history. SEDIMENT SAMPLING Sediment samples were collected bimonthly from June, 1970 to April, 1971 from five Stations, 1 (margin), 2, 3 (deeper-water), 5 (inlet), and 6 (outlet) (Fig. 1). These stations were along two transects with water depths ranging from 0.5 m to 4.0 m, one from near the margin to the deepest area in the lake, the other from the inlet to the outlet, with Station 3 as a crosspoint. In August, 1970, one additional station was set up near the other side of the lake margin, Station 4 (Fig. 1). Intact sediment cores were taken with a modified Kajak corer. In the f i e l d , the sediment cores were l e f t to stand for some moments to allow complete sedimentation. Water on the surface of the sediment was then decanted gradually. The top two 1.5 cm sediment sections, Sections\I and.II (i.e. total of top three centimeters of the core) were collected into two sterile 8-oz wide-mouth bottles. At each station, a composite sediment FIGURE 1 Marion Lake, showing depth contours i n meters and l o c a t i o n of the 6 sampling stations used i n t h i s study. Dir e c t i o n of water flow indicated by arrows. V e r t i c a l exaggeration of depth p r o f i l e s ; X _Q. 10 sample was obtained from three to four separate cores to give a total weight of approximately 30 g sediment. ISOLATION: MODIFIED DILUTION PLATE METHOD Isolation Technique The variety of the methods used for studying s o i l micro-organisms has. been outlined in Parkinson et a l . (1971) and Johnson and Curl (1972). It i s well-known (Warcup, 1960; Burges and Nicholas, 1961; Garrett, 1963; Pugh, 1969; Bhatt, 1970) that no single method can give a complete spectrum of the s o i l microflora. Furthermore, each technique must be modified through thorough preliminary testing to suit the particular s o i l under study (Parkinson et a l . , 1971). Of the more or less "standard" methods, the dilution plate method (Waksman, 1932) is most commonly used. The general criticism (Chesters, 1949; Warcup, 1957, 1960) of the method is that i t f a i l s to differentiate dormant spores and actively growing mycelia. Besides this imperfection, the dilution plate method has several other shortcomings: (a) Skinner, Jones, and Mollison (1952) pointed out that the plate count method may underestimate the numbers of organisms because clumps of cells may remain attached to s o i l particles which may have been settled down and not been drawn by plating or cells may be aggregated together in the suspen-sion; (b) It is well-known that in the dilution plate method as well as in the s o i l plate method (Warcup, 1950), the fast-growing fungi spread quickly and mask the slow-growing fungi, thus making i t d i f f i c u l t to record and isolate the latter; (c) Usually only one isolation medium is employed in the dilution plate method while i t is equally well-known that no single medium can support growth of a l l the fungi in soils; (d) Some workers (Tresner et a l . , 1954; Gochenaur and Whittingham, 1967) only study a pre-determined number of randomly selected colonies from each plate. This also 11 may result in the failure of recovering the slow-growing species. Modified Dilution Plate Method To compensate as much as possible for the disadvantages mentioned previously, a modified dilution plate method was used in the present study. It is outlined below: 1. Upon return to the laboratory, 10 g aliquots of sediment were placed in s t e r i l e 250 ml beakers containing 90 ml st e r i l e d i s t i l l e d water and a Teflon s t e r i l e stirring bar. Beakers were covered with aluminium f o i l . 2. The beaker was then put on a magnetic stirrer where the sediment suspension was dispersed for three minutes at moderate speed. 3. The speed of the magnetic stirrer was then reduced three-fold and while s t i l l s tirring, 10 ml of the suspension were transferred with a sterile wide-mouth pipette into another 90 ml of st e r i l e d i s t i l l e d water. 4. Step 2 was then repeated. 5. From this 1/100 sediment dilution, 1 ml aliquots were pipetted into each of six st e r i l e petri dishes (9.0 cm in diameter). 6. Two kinds of agar media were used in the dilution plates: Bacto Czapek Solution Agar, CZA (Difco Laboratories; Saccharose, 30 g; Sodium nitrate, 2 g; Dipotassium phosphate, 1 g; Magnesium sulfate, 0.5 g; Potassium chloride, 0.5 g; Ferrous sulfate, 0.01 g; Bacto-agar, 15 g in one l i t e r d i s t i l l e d water), and 2% Malt Agar, MA (Malt Extract, Difco, 20 g; Bacto-agar, 15 g in one l i t e r d i s t i l l e d water). Both media contained rose bengal at a concentration of 1:100,000 as a bacteriostatic agent, with pH adjusted to 6.5 before autoclaving. Approximately 18 ml of s t e r i l e , melted, and cooled (45°C) agar medium were poured into each petri, dish. Particles were dispersed evenly by rotating the petri dish gently on the table. The 12 dilution plates were prepared in tr i p l i c a t e with each of the agar media. 7. After solidifying, the plates were inverted and incubated at 23+1. 0°C. 8. Plates were, examined daily for six days. The examination was carried out by scanning the reversed plates with a dissecting microscope at 12.5X magnification. A l l the fungal colonies were circled by wax pencil along the hyphal margin as soon as they were recognized. Counts were made on each plate. Randomly, one plate from each t r i p l i c a t e agar medium group was selected for the isolation of fungi. After counting, a l l the fungal colonies which developed on the two selected plates (one from CZA group, one from 2% MA group) were transferred to Potato Dextrose Agar plates, PDA (Potato, 200 g; Bacto Dextrose, 20 g; Bacto-agar, 15 g; Di s t i l l e d water, 1 l i t e r ) for further study and identification. For the April, 1971 samples the fungal count was made as usual but isolation and identification were carried out only on the Station 3 sample. DRY WEIGHT AND STATISTICAL EXPRESSION For determination of dry weight of the sediments, 10 g aliquots of the sediment sample were dried at 105°C for 24 hours. The total viable propagules per gram of dried sediment was then expressed on a dry weight basis. Absolute density, expressed as the percentage of the total isolates; percentage frequency of spatial occurrence, as percentage of total stations showing positive recordings; and percentage frequency of seasonal occur-rence, as percentage of total seasonal collections showing positive record-ings, were calculated for each species or species group. 13 ORGANIC MATTER CONTENT The oven-dried sediment samples were used to determine the total organic carbon contents by using the LECO Carbon Analyzer 572-200 (Laboratory Equipment Corporation, Saint Joseph, Michigan), the results being expressed as percentage of organic matter. TEMPERATURE AND pH Using a thermometer, temperature of the sediment was recorded as soon as the sediment core was brought above the surface. pH was determined as " s o i l pH measured in water", according to the method of Black et a l . (1965). COMPARISON OF INCUBATION TEMPERATURES Besides the routine preparation and incubation of the plates at 23±1.0°C, six additional replicates, three on CZA and three on 2% MA were prepared from each sediment sample collected from Station 3 in Apr i l , 1971. These plates were incubated at 5°C for six weeks. 5°C was the approximate in situ temperature of the mud surface at the time of collection. Counts were made as usual. Eight plates, two from each of the t r i p l i c a t e sets were selected randomly for isolation of a l l the fungi vthat developed on them. Fungi were transferred onto PDA plates for further identification. IDENTIFICATION OF FUNGI If possible, fungi isolated were identified to species after growth on PDA. Some isolates were lost as they failed to grow on PDA or they were contaminated after transfer. No effort was made to culture those non-sporulating isolates on various other media for identification. They were grouped as hyaline and dark Mycelia S t e r i l i a . The following publications were especially useful for identification of the fungi isolated in this study: 'A Manual of Soil Fungi' (Gilman, 1957); 'The Genera of Hyphomycetes from Soil' (Barron, 1968); 'Dematiaceous Hyphomycetes' ( E l l i s , 1971); 'Hyphomycetes- An Account of Indian Species, except Cercosporae' (Subramanian, 1971); 'Illustrated Genera of Imperfect Fungi' (Barnett and Hunter, 1972); and individual monographic works, such as 'The Genus Cylindrocarpon' (Booth, 1966); 'Monophialidic Species of Paecilomyces' (Onions and Barron, 1967); 'The Genus Gliomastlx Gueguen' (Dickinson, 1968); and 'A Revision of the Genus Trichoderma' (Rifai, 1969). 15 RESULTS ANNOTATED LIST OF HYPHOMYCETES FROM MARION LAKE SEDIMENTS Acrogenospora E l l i s (?)Acrogenospora state of Farlowiella carmichaeliana (Berk.) Sacc., Sy l l . Fung., 9_: 1101, 1891. Colonies on PDA black, shiny, moist, with black gray aerial mycelium at the center. Conidiophores 120-300 u long, 8-10 u thick at the base, narrower at the apex, 4-6 u, dark brown, mostly simple, straight bearing a single conidium terminally (PI. I, f i g . 1) or rarely with short branches (PI. I, f i g . 2). Conidiogenous ce l l s percurrent or sympodial. Conidia solitary, broadly ellipsoidal to obovoid, (20-)25-27 X (24-)30-33(-35) u, with truncate base and conspicuous scar (PI. I, f i g . 2, arrow), dark brown, smooth, thick-walled, 0-septate. (?)Hyphopodia (PI. I, fi g . 3) globose to ovoid in chains, light brown, (12-)14-17(-22) X 11-14 y. Dr. K. Pirozynski (1973, personal communication) kindly examined a subculture sent to him and identified i t as Acrogenospora sp., probably conidial state of Farlowiella carmichaeliana. A precise determination of the species is d i f f i c u l t in view of the considerable v a r i a b i l i t y and atypical growth of members of Acrogenospora in a r t i f i c i a l culture (Mason, 1941; Hammill, 1972). One interesting feature of the fungus, the calyci-form conidiogenous c e l l s , was noticed, especially on young cultures of my isolate. This is a character shared with Eridophragmia and Endophragmibpsis. E l l i s (1966) described i t as follows: "Frequently when a conidium is shed a section of the wall of the lower part 16 >of the conidium remains attached to the top of the conidiophore forming a cup ..." (PI. I, f i g . 2). In Endophragmia, the conidiophore proliferates straight through the cup; while in Endophragmiopsis, the conidiophore sometimes proliferates straight through the cup forming another conidium at a higher level (PI. I, f i g . 4) but often grows out laterally to one side (PI. I, figs. 5, 6, arrow). The presence of hyphopodia in Endophragmiopsis also distinguishes i t from Endophragmia. These cups form in my material of Acrogenospora in the same manner as in Endophragmiopsis. The cup collapses very easily which may explain why i t s formation in Acrogenospora has not been previously emphasized, although i t was shown in Tubaki's i l l u s t r a t i o n (1969, PI. 2, A) of Acrogenospora sphaerocephala (Berk. & Br.) E l l i s (syn. Monotosporella  sphaerocephala (Berk. & Br.) Hughes). The non-septate conidia of this fungus differentiate i t from Endophragmia and Endophragmiopsis both of which have one-to five-septate and five-septate conidia. I believe that there is a very close relationship among these three genera but until more comparative studies have been carried out, i t is d i f f i c u l t to draw any further conclusions. Occurrence in Marion Lake: Isolated only once from Station 5; October, 1970. Alternaria Nees ex Wallr. Alternaria alternata (Fr.) Keissler, Beih. Bot. Zbl. , 2_9: 434, 1912. Colonies on PDA cottony, grayish-black to black, with white aerial mycelium at the center and submerged black mycelium towards the margin. Hyphae dark brown, 2-3 y thick. Conidiophores brownish, mostly simple, (10-)20-40 X 3-5 y. Conidia in chain, dark brown, muriform, ovate to obpyriform, rough with cylindrical or conical beak of 5-8 X 3~5 y, stouter 17 and shorter than that (2-3 y in diameter and up to 25 y in length) described by Simmons (1967), distinct basal pore at the end of the beak, conidial main body (excluding beak), (18-)22-27(-30) X (7-)ll-13 y. Occurrence in Marion Lake: Isolated once from Station 5, lower layer muds; October, 1970. A. alternata has a world-wide distribution. Its ecological and physiological characteristics have been summarized well by Domsch and Gams (1972). In Canada, i t has been recorded from soils of Ontario (Bhatt, 1970), Manitoba and Saskatchewan (Bisby, 1938; Sutton, 1973). Arthrinium Kunze ex Fr. Arthrinium sacchari (Speg.) E l l i s , Mycol. pap., C.M.I., 103: 11-12, f i g . 6, 1965. This genus has been treated well by E l l i s (1965) who included a key to the species. Later, two new species, A. f u c k e l i i Gjaerum and A. kamtschaticum Tranz. & Woronich. from Norway were added in his book, Dematiaceous Hyphomycetes ( E l l i s , 1971). Most members of the genus are found on dead leaves of Carex, Scirpus, Juncus, sugar cane or other grasses; few have been isolated from s o i l . Bhatt (1970) reported A. phaeospermum (Corda) E l l i s from Ontario white cedar forest s o i l . A. sacchari has been recorded only on sugar cane and other grasses. The present isolate agrees well with the description of A. sacchari ( E l l i s , 1965). It can be recognized easily by i t s lenticular conidia: dark brown, black in mass, with distinct hyaline germ s l i t (PI. I, f i g . 8, arrow), 6-80-9) y in face view and 4-5 y thick. Occurrence in Marion Lake: A. sacchari was isolated once from Station 5; February, 1971. 18 Aureobasldium Viala and Boyer Aureobasidium bolleyi (Sprague) von Arx, Verk. K. Nederl. Akad. Wetensch. Afd. Naturk. Tweede Reeks, 51: 47, 1957. Colonies on PDA moist, carrot-red, with aerial pinkish yellow hyphal ropes. Conidia borne on short conidiophores of 4-8(-10) X 1-3 y, hyaline, variable in shape, ovoid, 5-6 X 2-3 y or sausage, 3-5(-6) X 0.8-1.5 y. Domsch and Gams (1972) pointed out that the rarity of records is due to the d i f f i c u l t i e s of identification. Gams and Domsch (1969) \ found i t dominant in wheat soils. Occurrence in Marion Lake: A. bolleyi was isolated from a l l the stations except Station 1, and was found throughout the year. It was recorded more frequently in the summer and late winter. Aureobasidium pullulans (de Bary) Arnaud, Les Asterinees (in Ann. Ec. Agric. Montpellier, N. S. 16_: 39 (footnote), 1918. Colonies on PDA moist, dark brown to black. Hyphae hyaline, 3-4 y thick; or dark brown, thick-walled, up to 15 y thick, with slimy sheath around when aged. Conidia (PI. 1, f i g . 9) borne directly on denticles from hyphae, ovoid to ellipsoidal, hyaline, 6-9(-14) X 3-4 y. Occurrence in Marion Lake: Infrequent. A. pullulans may be recorded under i t s synonym Pullularia pullulans (de Bary) Berkhout in many l i s t s of s o i l fungi. It i s known as a cosmo-politan species, found on dead plants, wood, pulp and paper or isolated from a i r , fresh water, and s o i l . A. pullulans is considered also to be an " i n i t i a l colonizer" on freshly fallen leaves (Kendrick and Burges, 1962; Pugh and Mulder, 1971). 19 Beauveria V u i l l . Beauveria basslana (Bals. -Criv.) V u i l l . , B u l l . Soc. bot. Fr. , 59_: 40, 1912. Colonies on PDA powdery, white to pale yellow, i n dense r i n g s . Conidiogenous c e l l s i n groups flask-shaped with very long filaments, 7-9(-ll) X 2-3 u. Conidia borne on the long filament i n acropetal succes-sion, hyaline, globose to ovoid, 1.5-2.5 X 1-2 \i (PI. 1, f i g . 7). The conidium-bearing long filament was described by Barron (1968) as "long, r a c h i s - l i k e , sometimes bent or tortuous I agree with Benham and Miranda (1953) that a pronounced zigzag filament i s d i f f i c u l t to recognize. The taxonomy and morphology of the species of the genus Beauveria have been investigated by Benham and Miranda (1953), MacLeod (1954) and de Hoog (1972). Occurrence in Marion Lake: B. bassiana was w e l l d i s t r i b u t e d throughout the lake and equally abundant i n surface and lower layers of muds. I t occurred a l l year round, although more i s o l a t e s were recorded i n the winter. B_. bassiana has been well-known as an entomogenous fungus causing white muscardine. I t i s r a r e l y recorded from s o i l except from Ontario by Barron (1968) and Bhatt (1970) and from Wisconsin by Gochenaur and Whittingham (1967). Wang (1965) found i t twice during her study of pulp and paper fungi. B o t r y t i s Pers. ex Fr. B o t r y t i s cinerea Pers. ex. Fr., Syst. Mycol., j3: 396, 1832. PI. I, f i g s . 10, 11. Occurrence i n Marion Lake: More often i s o l a t e d i n the winter and confined to surface muds of Stations 1, 2 and 3. PLATE I FIGS. 1-6. (?)Acrogenospora state of Farlowiella carmichaeliana. Fig. 1. Conidiophore bearing single conidium terminally, X400. Fig. 2. Conidiophores, showing short branch; 'cup' at the tip of the conidiophore; and conidia scar (arrow), X400. Fig. 3. (?)Hyphopodia, X400. Fig. 4. Conidiophore proliferates straight through the cup, X1000. Fig. 5. Conidiophore, showing lateral growth, X1000. Fig. 6. Same as Fig, 5, but focus on cup (arrow), X1000. FIG. 7. Beauveria bassiana. Flask-shaped conidiogenous cells with long filaments and conidia, X1500. FIG. 8. Arthrinium sacchari. Lenticular conidia, showing germ s l i t (arrow), X1000. FIG. 9. Aureobasidium pullulans. Conidia borne on short denticles from hypha, X1000. FIGS. 10, 11. Botrytis cinerea. Fig. 10. Dichotomously branched conidiophores, X100. Fig. 11. Mature ampullae covered with conidia, X400. 22 Cephalosporium Corda The genus Cephalosporium Corda is one of the fungi easiest to identify to genus and one of the most d i f f i c u l t in which to make species determinations (Barron, 1968). Due to the great variations of the strains and inadequate knowledge of the genus, the possibility of meaningful specific identifications i s doubtful. Sukapure and Thirumalachar (1963, 1965, 1966a, 1966b) have investigated Indian species of Cephalosporium extensively. Based mainly on the cultural coloration, they divided the genus into four major groups: Cephalosporium acremonium group, pink, pale rose to red; Cephalosporium curtipes group, white or colorless; Cephalosporium asperum group, white, then ashy-gray to tan; Cephalosporium chrysogenum group, white to subhyaline then yellow. Keys to the species of each group were proposed in their most recent work (1966a). Gams (1970) defined the genus Acremonium broadly to accommodate those species previously belonged to Cephalosporium, Acremonium, and Gliomastix. I found that Cephalosporium isolates from Marion Lake could be identified rarely using Sukapure and Thirumalachar's key. Cephalosporium acremonium Corda, Icon. Fung., _3: 11, f i g . 29, 1839. Colonies on PDA dull pink, dense, moist, occasionally with white floccose or rarely funiculose aerial mycelium. Conidiophores straight, hyaline, simple, non-septate, slightly tapering towards the tip (PI. II, f i g . 12), 4-6(-12) X l-2(-3) u. Conidia forming slimy head at the tip of conidiophores (PI. II, f i g . 13), hyaline, e l l i p t i c a l to oval, sometimes slightly curved, 4-6(-12) X 1-2 y (PI. II, f i g . 14). Occurrence in Marion Lake: fj. acremonium was one of the species distributed throughout the lake, with higher density at Station 3. It occurred in a l l 23 seasons although more abundant in f a l l and winter. fj. acremonium is the most common species of this genus. It has been found usually in soils (Waksman, 1916; Bisby at al., 1933; Bisby, 1938; Subramanian, 1952; Miller et a l . , 1957; Hodges, 1962; Tubaki, 1965; Gochenaur and Whittingham, 1967; Sutton, 1973). Tubaki (1954) recorded this species from dung and Pugh (1962) isolated i t from salt marsh s o i l where i t was one of the most frequently isolated fungi in the new marsh. Cephalosporium incarnatum Sukap. & Thirum. , Mycologia, 55_: 566, figs. 11-15, 1963. Colonies on PDA not moist, reddish l i v i d purple with pale grayish rose, slightly funiculose aerial mycelium (PI. II, f i g . 15); reverse of the colony, dark reddish purple. Conidiophores simple, straight, non-septate, hyaline, 7-15 X 1-2(-3) y. Conidia forming conidial head at the tip of the conidiophore, hyaline, oval to e l l i p t i c a l , occasionally slightly curved, 4-5(-6) X l-1.5(-2) y (PI. II, f i g . 16). Occurrence in Marion Lake: A total of seven isolates represented this species. Three isolates were collected in October, 1970, and one each from June, August, December, 1970 and February, 1971. It was not recorded from Stations 3 and 6. This species was isolated originally from s o i l samples of Kolhapur, Poona by Sukapure and Thirumalachar (1963). Since then, I am not aware of any other record of this fungus. Cephalosporium incarnatum Sukap. & Thirum. var. macrosporum Sukap. & Thirum., Mycologia, 55: 568, figs. 16-20, 1963. Colonies on PDA hazel to brownish black in rings, reaching 4.5 to 5 cm in 20 days at 25°C. Hyphae 1.5-2 y thick, with no tendency of forming 24 ropes (PI. II, f i g . 17). Conidiophores (PI. II, f i g . 18) hyaline, simple or rarely branched, straight, sometimes slightly bending to one side, tapering towards the tip , 0.5 ji at the tip and 1-2 y broad at the widest part, (7-)13-17(-21) y long. Conidia in slimy heads (PI. II, f i g . 17) at the tip of conidiophores, hyaline, oblong to cylindrical, smooth, often with two o i l globules (PI. II, f i g . 18). Chlamydospores (PI. II, f i g . 19), dark brown, abundantly on the aged culture, spherical, subglobose or ovoid, intercalary, single or in chain, 6-8(-11) X 5-6 y. My material differs slightly from Sukapure and Thirumalachar's description in that the conidiophores are longer, 20-40 y and no chlamydospores were reported in their material. Occurrence in Marion Lake: This is probably the f i r s t record of C_. incarnatum var. macrosporum from Canadian s o i l . It was found commonly in Marion Lake. A seasonal fluctuation was shown, with maximum occurrence in August and October, 1970. It was collected more often from Station 2 and was never isolated from Station 5. Cephalosporium incoloratum Sukap. & Thirum. , Sydowia, 19_: 171, 1965. Colonial characters agree with Sukapure and Thirumalachar's description (1965). Conidiophores (PI. II, f i g . 20) straight, non-septate, simple, occasionally branched, tapering gradually to the tip, 23-40(-50) X 1-2.5 y. Conidia forming slimy balls at the tip of conidio-phores, hyaline,.elliptical, smooth, 2-4 X 1.5-2 y, slightly smaller than that of the type being 3-5 X 1.2-1.5 y. Occurrence in Marion Lake: This is possibly the f i r s t report of this species since i t was described. The only two isolates recorded were one from Station 2, surface muds, December1970, and one from Station 1, lower layer muds, February, 1971. 25 Cephalosporium khandalense Thirum. & Sukap., Mycologia, _58_: 359, f i g . 1, 1966. PI. II, f i g . 21. Occurrence in Marion Lake: More frequently collected from Station 2 and absent at Stations 1 and 5; appeared from October, 1970 to February, 1971. Chloridium Link Chi or id ium chlamydosporis (van Beyma) Hughes, Can. J. Bot. , 3_6: 748, 1958. Colonies on PDA slow growing, grayish black to black, tough with thin white to whitish gray margin. Conidiophores (PI. II, f i g . 22) brown, simple, straight, septate; proliferation frequent, 60-150 X 2.5-3.0 p. Conidia (PI. II, f i g . 22) hyaline, ovoid, forming slimy balls, 3.5-5 X 2.5-3 p. Chlamydospores (PI. II, f i g . 23): brown globose to ovoid, single and terminal, 4-5(-6) p in diameter. Occurrence in Marion Lake: C_. chlamydosporis was isolated throughout the year and occurred in a l l the stations except Station 6. Besides one isolate from lower layer muds of Station 2, the rest of the. isolates were from surface muds only. C_. chlamydosporis seems to have worldwide distribution and i s recorded mostly from forest soils (Domsch and Gams, 1972). Barron (1968) stated that i t i s the most commonly isolated species of the genus and is found frequently in soils high in organic matter. Its isolation from Marion Lake with an organic matter content of approximately 25-30% i s not therefore surprising. Aside from this report of C_. chlamydosporis from Canadian s o i l , i t has been reported also from Ontario (Bhatt, 1970) and Manitoba (Sutton, 1973). PLATE II FIGS. 12-14 Cephalosporium acremonium. Fig. 12. Simple conidiophores, X1000. Fig. 13. Conidial heads at the tips of conidiophores, X100. Fig. 14. Conidia, X1000. , FIGS. 15-16. CJ. incarnatum. Fig. 15. Funiculose aerial mycelium, X400. Fig. 16. Conidiophores and conidia, X1000. FIGS. 17-19. C_. incarnatum var. macrosporum. Fig. 17. General appearance of hyphae, conidiophores, and conidial heads, X100. Fig. 18. Simple conidiophores and conidia, X1000. Fig. 19. Chlamydospores, X400. FIG. 20. jC. incoloratum. Simple conidiophores and conidia, X1000. FIG. 21. C. khandalense. - Conidiophores and conidia, X400. FIGS. 22, 23. Chloridium chlamydosporis. Fig. 22. Conidiophores, showing the proliferating phialides and collarettes and conidia, X1000. Fig. 23. Chlamydospores, X1500. 28 Chrysosporium Corda Carmichael (1962) revised the genus Chrysosporium and proposed a key to the 13 species he recognized, including two new species, C_. asperatum Carmichael, and fJ. tropicum Carmichael, and one new name, -C. inops Carmichael. Pitt (1966) described two new species, jC. fast id ium Pitt and >C. xerophilum Pitt from Australian prunes, both xerophilic. However, the rather broad generic concept of Carmichael and the relation-ships between Chrysosporium, Sporothrix and Sporotrichum are s t i l l the subject of much discussion (Mueller, 1964a, 1964b, 1965; Barron, 1968; Taylor, 1970). Chrysosporium pannorum (Link) Hughes, Can. J. Bot., _36_: 749,. 1958. Colonies on PDA buff to hazel, more or less powdery with white to grayish white aerial mycelium, marginal zonation shown in age; reverse brown. Carmichael (1962), Tubaki and Asano (1965), Dickinson and Dooley (1969) noted the great colour variation of this species. The constant microscopic characters described below related this fungus to fJ. pannorum. Conidiophores erect, v e r t i c i l l a t e or irregularly.branched. Conidia (PI. I l l , f i g . 24). hyaline, pyriform with characteristic truncate base, terminal or lateral, single or in chain, thick-walled, smooth or roughened, (2.5-)3-4(-5) X 2-3.5 y, slightly smaller as compared with 4-8 X 3-6 y (mostly 5-6 X 4-5 y) of the type described by Carmichael but similar to that, 2-5 X 2-3.5(-4) y reported by Tubaki and Asano (1965). Occurrence in Marion Lake: C. pannorum was isolated only once from Station 1; October, 1971. C. pannorum is probably ubiquitous. Barron (1968) and Bhatt (1970) found i t to be one of the most frequently isolated fungi from Ontario s o i l when the dilution plate method was applied. 29 Cladosporlum Link ex Fr. Cladosporium cladosporioides (Fresen.) de Vries, Contribution to the knowledge of the Genus Cladosporium Link ex Fr., :57, 1952. Colonies on PDA olivaceous black; reverse greenish black to black. Conidiophores 2-6 y thick, up to 300 y long, dark brown, septate. Ramo-conidia, 0-septate, rarely 1-septate, smooth or finely roughened, 10-20(-30) X 4-5 y. Conidia pale brown, oval to ellipsoidal in long chains, 0-septate, smooth or roughened, 4.5-8 X 2.5-3.5 u; both ramo-conidia and conidia with one or more prominent scars ('hila') at the ends. Occurrence in Marion Lake: C_. cladosporioides was one of the species dis-tributed throughout the lake, but was isolated mainly from surface muds. A striking seasonal variation was observed. It was recorded only in winter samples. fj. cladosporioides can be found under Hormodendron cladosporioides (Fres.) Sacc. in older reports (Jensen, 1931; Chou and Stephen, 1968). However, Hormodendron Bonorden is now generally treated as a synonym of Cladosporium. It also may not be different from fj. herbarum. Wang (1965) considered those isolates with smooth conidia she formerly assigned as C_. cladosporioides as a strain of C_. herbarum. For ecological and physiological data of C_. cladosporioides and Cj. herbarum, Domsch and Gams' work (1972) should be referred to. Cladosporium herbarum (Pers.) Link ex S. F. Gray, Nat. Arr. Br. PI., 1: 556, 1821. Colonies on PDA olivaceous black; reverse greenish black. Conidiophores brown, septate, 5-76-10) y thick, up to 250 y long. Ramo-conidia 0-1 septate, 15-25(-34) X 5-6 y. Conidia ovoid to broad e l l i p t i c a l in long chains, 8-10 X 4-5 y (PI. I l l , f i g . 25). Ramo-conidia 30 and conidia conspicuously verrucose, with distinct scars at the ends (PI. I l l , f i g . 26). Larger and verrucose conidia together with thicker and geniculate conidiophores are based to assign this fungus. Occurrence in Marion Lake: As in the case of C. cladosporioides, fJ. herbarum was distributed a l l over the lake. Furthermore, i t was con-fined s t r i c t l y to the surface muds. It also showed the highest density in December, 197.0, and was not found in the June and August, 1970 samples. This finding contradicts that of Bhatt (1965) who did not find C. herbarum in his winter samples from Ontario cedar forest soils. Consequently, he attributed the absence of C_. herbarum to low temperature sensitivity. Mishra (1965, 1966b, 1972), Mishra and Srivastava (1970) and Moubasher and El-Dohlob (1970) in studying the seasonal fluctuation of s o i l and air fungi from India and Egypt reported the presence of fJ. herbarum in winter and spring and complete absence during high-temperature months. However, i t should be noted that the temperature of winter and spring in these areas is rather high. It ranged from 19 to 35°C for Egyptian s o i l (Moubasher and El-Dohlob, 1970) and from 15 to 30°C in India (Mishra, 1972). The absence of fJ. herbarum in summer may be attributed not only to the high temperature but also the dry s o i l . fJ. herbarum is isolated frequently from either functional or dead plant material and is considered as "primary colonizer" (Hogg and Hudson, 1966; Pugh and Mulder, 1971; Tubaki and Yokoyama, 1973). Potter and Baker (1961) found i t commonly in the bottom muds of Roger Lake, Montana. This coincides with i t s occurrence in Marion Lake. C_. cladosporio ides and. fJ. herbarum are very common cosmopolitan species. References reporting this fungus are numerous. It seems certain that one can expect to find C_. herbarum, the most common species in the genus, from soils a l l over the world and on a great variety of substrata. 31 Cladosporium macrocarpum Preuss, in Sturm's Deut. FI., 3_: 27, 1848. Colonies on PDA grayish black, fast growing comparing to that of C_. cladosporioides and fj. herbarum, reaching 7 cm in diameter in 20 days at 25°C, with white to gray aerial mycelium at the center and irregularly hyphal outgrowths at the margin, especially when aged; reverse black. Conidiophores (PI. I l l , figs. 27, 28) dark brown to light brown at the t i p , unbranched, septate, strongly nodose and geniculate at the upper part, 4-5(-7) y wide, up to 10 y at nodose, and variable in length, up to 350 y long; mostly 100-250 y, with distinct, large scars (PI. I l l , f i g . 28, arrow). Conidia (PI. I l l , f i g . 29) in chains, usually more than two chains on each conidiophore, oval, el l i p s o i d a l , cylindrical, usually 0-1 septate, with or without constrictions at the middle part or at the septum; when constrictions present, conidia appear peanut-shaped, scars not distinct, pale to dark brown, densely verrucose, (5-)7-18(-21) X (3-)6-8(-10) y. This isolate differed slightly from those described by E l l i s (1971) and Subramanian (1971) in that 2-3 septate conidia are seen only in a few occasions as compared with "frequently 2- and 3-septate conidia". Occurrence in Marion Lake: fj. macrocarpum was represented by a single isolate from Station 1 in December, 1970. This substantiates the state-ment by Domsch and Gams (1972) that on the whole i t is recorded more rarely than fj. herbarum and fJ. cladosporioides. fJ. macrocarpum also has been found in Manitoba and Saskatchewan (Sutton, 1973). Cladosporium musae Mason, apud Martyn in Mycol. pap., C.M.I., 13: 2-3, 1945. Occurrence in Marion Lake: Occurred once from Station 3, surface muds; August, 1970. 32 Cordana Preuss Cordana pauciseptata Preuss, in Linnaea, 2A_: 129, 1851. Colonies on PDA shiny black with grayish black center. Hyphae pale to dark brown, smooth or roughened, 2-3.5 y thick. Conidiophores (PI. I l l , f i g . 30) pale brown to dark brown, simple, straight, septate, 4.5-6 wide at the base and tapering towards the tip to 3-4 y; then terminating with hyaline, swollen conidium-bearing apex; 5-7 y in diameter, variable in length, (50-)90-150(-190) y. Conidia (PI. I l l , figs. 31, 32) forming clusters at the tip of conidiophores, borne on denticles of swollen apex (conidiogenous c e l l ) , ovoid to broadly ellipsoidal, brown, 1-septate, with dark brown to black band of 0.8-1.2 y thick at the septum, distinct (?)germ pores at the ends which attached to the swollen apex, 8-10(-16) X 5-6 y. Chlamydospores, pale to dark brown, borne singly on short, simple, lateral branches (PI. I l l , f i g . 33) or rarely in groups on differentiated branches (PI. I l l , f i g . 34) from vegetative hyphae, ovoid, 7-9(-11) X 5-6 y. Hughes (1955) reviewed the genus Cordana and redescribed the type species C_. pauciseptata. My isolate agrees generally with his description and i l l u s t r a t i o n of that species. Contrary to his statement that "... on potato-dextrose agar abundant conidiophores develop almost to the margin of the colonies my material showed that on PDA, chlamydospores were abundant but conidiophores were observed rarely and on 2% MA, conidiophores, conidia and chlamydospores were found to be equally abundant. However, E l l i s (1971) and Subramanian (1971) did not mention chlamydospores in their descriptions. Proliferation of the conidiophore was not observed in my collections either. Occurrence in Marion Lake: This fungus was collected twice from Station 3: in December, 1970 and April, 1971. PLATE III FIG. 24. Chrysosporium pannorum. Conidia, X1000. FIGS. 25, 26. Cladosporium herbarum. Fig. 25. Conidia in chains, X400. Fig. 26. Ramo-conidia and conidia, showing scars and verrucose walls, X1000. FIGS. 27-29. fJ. macrocarpum. Figs. 27, 28. Nodose and geniculate conidiophores, showing scar (arrow), and conidia, Fig. 27, X600. Fig. 28, X1500. Fig. 29. Conidia, X1000. FIGS. 30-34. Cordana pauciseptata. Fig. 30. Conidiophore and conidia, X1000. Fig. 31. Conidial clusters at the tips of conidiophores, X600. Fig. 32. Conidia, X1500. Figs. 33, 34. Chlamydospores, X1000. 34 PLATE III 35 fj. pauciseptata is found commonly on wood, bark or leaves. It has been reported from Canada, Europe, France, United States (Hughes, 1955), Australia (Tubaki, 1965). Besides the present report of Cj. pauciseptata from Marion Lake muds, the other two reports from soils are those of Routien (1957) from New York and Barron (1968) from Ontario. Cylindrocarpon Wollen. Cylindrocarpon destructans (Zins.) Scholten, Neth. J. Plant Path., 70: (suppl. 2): 9, 1964. (conidial state of Nectria radicicola Gerlach & Nilsson, Phytopath. Z., 48: 251-257, 1963.) Colonies on PDA brown to chestnut with aerial mycelium more or less floccose, beige to grayish brown. Conidiophores (PI. IV, f i g . 35) terminating with phialides, 18-30 X 2.5-4 y. Microconidia oval to e l l i p -t i c a l , hyaline, 5-7.5 X 2.5-3.5 y. Macroconidia (PI. IV. f i g . 35) cylindrical, with round ends; one end 5-7.5 y wide and slightly narrowing, 4.5-6.5 y towards the other.end, straight or slightly curved, 1-3 septate, mostly 3-septate, (20-)30-40(-50) y long. Chlamydospores globose or oval, light or dark brown, terminal or intercalary, single or in chain, smooth or rarely roughened, 5.5-6.5(-9) y in diameter. Occurrence in Marion Lake: Although with low density (0.7%), this fungus was found from a l l six stations in Marion Lake. It was isolated more frequently from the surface muds, in contrast with the general finding that C. destructans, increased in density in deeper soils (Bisby et a l . , 1935; Matturi and Stenton, 1964). It appeared in Marion Lake f i r s t in August, 1970, and increased gradually to reach i t s highest density in February, 1971. 36 The occurrence of C. destructans in Marion Lake was expected since i t s distribution is world-wide, with particular frequency from forest soils. It is often associated with plant roots (Booth, 1966; Barron, 1968; Domsch and Gams, 1972). Cylindrocarpon didymum (Hartig) Wollen., Fus. 'autogr. del., ed. 2, 650, 1926. Colonies on PDA reddish brown to chestnut with light brown to hazel, floccose aerial mycelium. Conidiophores simple, occasionally once-branched, septate, (60-)80-100(-110) X 3-4 y, with terminal phialides; 5-25 X 2.5-3.5 y. Microconidia (PI. IV. f i g . 36) oval, hyaline, 5-6.5 X 3-3.5 y. Macroconidia (PI. IV, f i g . 36) e l l i p t i c a l to cylindrical, straight or slightly constricted at the middle or septum, 0-1 septate; 0-septate conidia 10-15 X 3.5-4.5 y; 1-septate conidia 15-25 X 4-5 y. There are some 0-septate conidia with intermediate size, 7-9 X 3-3.5 V, longer than 0-septate microconidia but narrower than 1-septate macro-conidia. Chlamydospores (PI. IV, f i g . 37) globose to broadly cylindrical, dark brown, mostly in chains, with numerous o i l globules, 10-20 X 8-12 y. Occurrence in Marion Lake: C_. didymum was found only from surface sedi-ments of Stations 2, 3 and 4. A total of five isolates: three from October, 1970, and two from December 1970, were recorded. C_. didymum has been reported from s o i l and on plant roots (Domsch and Gams, 1972). Cylindrocarpon (?)lucidum Booth, Mycol. pap., C.M.I., 104: 21, 1966. Occurrence in Marion Lake: C_. (?)lucidum occurred twice in February, 1971 sample: once from Station 1 and once from Station 6. Epicoccum Link Epicoccum purpurascens Ehrenb. ex Schlecht., Synop. PI. crypt.: 136, 1824. Colonies on PDA white, beige to reddish orange becoming black in age due to mature dark conidia, floccose. Sporodochia abundant, black. Conidiophores (P.l. IV, f i g . 38) usually grouped together tightly, simple or rarely branched, septate, hyaline to light brown, short and plump, 6-15 X 3-3.5(-5.5) p. Conidia single, terminal, dark brown, muriform, pyriform to lobed-like subglobose, scaly roughened wall, with ring-shaped basal c e l l (PI. IV, f i g . 39, arrow r) and large scar (PI. IV, f i g . 39, arrow s), 15-21 X 13-18 p. The characteristic scaly muriform conidia made identification of this material easy. Occurrence in Marion Lake: Jf. purpurascens was isolated only once in this study from Station 3 in April, 1971. This cosmopolitan fungus has been reported frequently from various plants and soils (Schol-Schwarz, 1959; E l l i s , 1971; Subramanian, 1971; Domsch and Gams, 1972). It was found not uncommonly from Ontario soils (Barron, 1968; Bhatt, 1970), and from Manitoba and Saskatchewan on twigs, bark stems or roots (Bisby, 1938; Sutton, 1973). Geniculosporium Chesters and Greenhalgh Geniculosporium serpens Chesters & Greenhalgh, Trans. Brit. Mycol. Soc, 47: 400, 1964. (Geniculosporium state of Hypoxylon serpens (Pers. ex Fr.) Kickx, Flore Crypt. Louvain: 115, 1835.) Occurrence in Marion Lake: Infrequent. 38 Geotrichum Link Geotrichum candidum Link ex Persoon, Mycol. Eur op. , 1_: 26, 1822. This fungus is assigned to G_. candidum on the basis of i t s white, thin, cottony to powdery colony and characteristic cylindrical to barrel-shaped, hyaline arthroconidia (PI. IV, f i g . 40) in long chains formed by fragmentation of the vegetative hyphae. The size of conidia in this isolate is. 4-7 X 2-3.5 u . Carmichael (1957) amended G. candidum and appended 55 synonyms. He doubted the perfect stage, Endomyces la c t i s (Fres.) Windisch proposed by Windisch (1951) because asci and ascospores were found only in one strain on one occasion and were never seen again. More recently Butler and Petersen (1972) described Endomyces geotrichum Butler & Petersen from Puerto Rico soils as the perfect state of G. candidum, however, they concluded that "... the relationship of E_. geotrichum to the complex of asexual fungi now referred to G. cand idum remains to be determined". Occurrence in Marion Lake: -G. candidum was one of the most widely d i s t r i -buted fungi in Marion Lake muds. This finding agrees with the results obtained by Potter and Baker (1961) who reported that the species was common in the bottom mud of a l l four stations in Rogers Lake and two stations (total of four stations) in Flathead Lake, Montana. Although with relatively low density, 1.34%, i t was equally abundant in surface and lower layer muds except at Station 3 where a l l the isolates of G_. cand idum were from surface muds. It was completely absent in June, 1970, and appeared during the rest of the year. This world-wide species i s isolated frequently from s o i l (Carmichael, 1957;; Gilman, 1957; Barron, 1968; Subramanian, 1971). 3 9 Gliocladlum Corda Gliocladium cateriulatum Gilman & Abbott, Iowa State C o l l . Jour. S c i . , 1: 303, f i g . 37, 1927. Occurrence i n Marion Lake: Four out of the s i x i s o l a t e s assigned to G. catenulatum were from Station 3 and one each from Stations 1 and 2. Generally i t was found on surface muds, and was i s o l a t e d only i n October, 1970. Gliocladium roseum Bainier, B u l l . Soc. Mycol. Fr. , >23: 111-112, PI. 15, f i g s . 1-6, 1907. Colonies on PDA at f i r s t white becoming pale pink to salmon, sometimes with yellow pigments d i f f u s e d into agar, floccose to s l i g h t l y funiculose, with powdery f r u i t i n g area; reverse pale pink to pinkish yellow. Conidiophores (PI. IV, f i g . 41) long, slender, septate, branching at t i p , terminating with compactly aggregated p h i a l i d e s . Conidia forming large slimy b a l l s (PI. IV, f i g . 42), hyaline or pink i n mass, e l l i p t i c a l , smooth, 4-6(-7.5) X (2-)3-4 p. Occurrence in Marion Lake: In the present study, although with r e l a t i v e l y low density (0.63%), G_. roseum was one of the most widely d i s t r i b u t e d fungi, e s p e c i a l l y i n the surface muds. I t occurred throughout the year. There i s a s l i g h t i n d i c a t i o n that i t i s more abundant in winter, i n agreement with Gochenaur's (1964) report of a maximum i n January and a minimum in autumn in Wisconsin s o i l s , although Bhatt (1965) concluded that the highest f r e -quency was i n summer and the lowest frequency i n spring and winter i n Ontario s o i l s . Studies of _G. roseum in a l l respects - taxonomy, ecology, physi-ology and culture have been summarized well by Pugh and Dickinson (1965) and 40 and Domsch and Gams (1972). Gliocladium virens M i l l . , Gidd. & Fost., Mycologia, 49: 792, 1957. PI. IV, f i g . 43. Other.than the slightly larger conidia, 6-7(-8) X 3.5-4(-5) u , this material showed no difference from the original description of the type from cultivated s o i l in Georgia. Occurrence in Marion Lake: This species was collected mostly in summer samples and distributed throughout the lake when i t was recorded. However, i t was less common than Trichoderma viride Pers. ex Gray aggr. R i f a i . Hodges (1962) in his survey of forest s o i l fungi from 10 southern states recorded (5. virens from Alabama, Arkansas, Florida, Mississippi and South Carolina. Since then, to my knowledge, i t has never been included in any l i s t of s o i l fungi. Nevertheless, von Arx (1970) con-sidered G. virens together with G. roseum as common species of the genus. The rarity of reports of this species may be attributed to i t s great simi-l a r i t y to T. viride and the resulting misidentifications. In fact, in their study of antibiotics, Webster and Lomas (1964) discovered that Weindling's and Brian's gliotoxin- and viridin-producing isolates of T_. viride were actually G. virens, and concluded that many, perhaps most, of the reports of antagonism by Trichoderma actually relate to G. virens. Gliomastix Gueguen Gliomastix murorum (Corda) Hughes, Can. J. Bot., _36: 769, 1958. Colonies on PDA at f i r s t white to pink, quickly becoming grayish black to black with conidia formation, effuse floccose with radiating grayish aerial mycelium; reverse dark brick black. Phialides arising 41 directly from hyphal ropes (PI. V, f i g . 48), simple or rarely branched, straight or slightly sinuous with one basal septum, hyaline and smooth turning roughened with dark deposits at the d i s t a l end,. 2-3 y wide at the basal part, tapering towards the apex, 0.8-1.2 y thick, . (18-)25-30(-35) y long. Conidia subglobose to oval, at f i r s t forming large black slimy balls on those hyphae close to the agar surface, later produced in simple, long-chain with separators (?black deposits) between the conidia on the aerial hyphal ropes intermingling with slimy conidia heads (PI. V, figs. 49, 50), occasionally conidial chains sliming down from the apex (PI. V, f i g . 51), i n i t i a l l y smooth and hyaline; then some roughened and turning dark olivaceous brown to black in age due to black granular deposits on the wall, 3.5-5.5 X 2.5-3.5 y (PI. V, f i g . 48). In spite of Mason's (1941) doubt that G_. murorum var. felina is a separate taxon, Dickinson (1968), in his monographic treatment of the genus Gliomastix, retained this variety and distinguished i t from type species of the genus, G_. murorum in that the latter has subglobose to ovoid conidia in long chains. Dickinson found that the non-catenulate conidia of G_. murorum var. felina appeared to be constant under various conditions, and hence recognized i t at the varietal level. In this study of Marion Lake, four isolates represented G_. murorum. In examining the young cultures on PDA, they were originally assigned to G_. murorum var. felina on the basis of the slimy conidial heads. Later, i t was found that variable amounts of long-chain conidia formed on aerial hyphae too. The species seems to have as a general characteristic that conidia forming the slimy head are more elongate while those forming long chains are shorter to subglobose. However, some long-chain conidia are ovoid, or subglobose conidia may be mixed with ovoid conidia in a slimy head. 42 I would, therefore, question the val i d i t y of retaining CJ. murorum var. felina and have assigned the four isolates from Marion Lake to G. murorum. A comparative study of the single spore cultures would serve to c l a r i f y the true relationships of G. murorum and G. murorum var. felina. Occurrence in Marion Lake: During the distributional study, (3. murorum was isolated once each from Station 2, August, 1970; Station 4, December, 1970; and Station 1, February, 1971. A l l isolates were confined to surface muds. Humicola Traaen (?)Humicola sp. Colonies on PDA slow growing, grayish white, soon turning grayish black to black in the center, moist, occasionally with scarce whitish gray aerial hyphae; reverse black. Hyphae hyaline, 1.0-2.5 u thick. Conidia (PI. IV, f i g . 44), borne on sometimes slightly inflated tips of vegetative hyphae or on lateral branches, single, in pairs or in chains, light to dark brown, globose, oval or pyriform, (5-)7-10(-12) X 5.5-6.5(-7) y. Inter-calary chlamydospores abundant, especially on old culture, light to dark brown, mostly in long chains, greatly variable in shape and size, sub-globose, oval, or cylindrical, up to 14 X 8 y. Phialidic state present, (?)phialides, Cephalosporium-like, short, simple, hyaline, 6-12(-17) X 1.5-2.5 y. Phialoconidia forming slimy head at the tip of phialide, ellipsoidal to cylindrical, (4-)5-8(-10) X (15-)2-3 y (PI. IV, f i g . 45). The genus Humicola was erected by Traaen in 1914 and based on two species, H. fuscoatra Traaen (type) and H. grisea Traaen. White and Downing Filed under DAOM 139466, National Fungus Herbarium, Plant Research Institute, Ottawa, Ontario. 43 (1953) dealt with the various nomenclatural problems in the genus and dis-cussed in detail the geographic distribution, morphological and physio-logical characters of H. grisea. Since then, H. nigrescens Omvik (Omvik, 1955); H. brevis (Gilman & Abbott) Gilman (Gilman, 1957); H. allopallonella Meyers & Moore (Meyers and Moore, 1960) have been described. Fassatiova (1967) emended the genus to include those with coloured hyphae and also provided a key to the species, including H. bfuririea Fass. and H. minima Fass., newly described in her work. However, the vali d i t y of her taxonomic key was questioned by de Bertoldi e_t al. (1972) simply because the charac-ters used to separate species, e.g., colour of hyphae and conidia are subject to change depending on growth conditions. Instead, they suggested that a genetical taxonomy within this genus should be tried. Based on the presence of the dominant dark conidia, chlamydospores as well as phialoconidia state, my material seems to f i t into Humicola better than any of the related genera. However, i t could not be referred to any of the known species of Humicola. It resembles H. nigrescens in the morphology of dark conidia and intercalary chlamydospores but differs in having smaller conidia, chlamydospores and numerous phialoconidia. My fungus also bears some similarities with Phialophora mustea Neergaard. However, the size and arrangement of chlamydospores are different from those of the presumed type culture of P_. mustea and Wang's isolate of this species (personal communication, 1972). Furthermore, Dr. Wang has suggested the transfer of P. mustea to Humicola. I am inclined to accept Barron's (1968) conclusion that "the taxonomy of the genus Humicola is confused and a con-tribution elucidating the relationships and differentiating the described species on the basis of a comparative study would be welcome." Occurrence in Marion Lake: Despite i t s uncertain identity, (?)Humicola sp. 44 was the most widely distributed and most frequently isolated fungus in Marion Lake sediments. It showed no significant difference in ve r t i c a l distribution, although i t was more abundant on the surface muds. Seasonal variation was noted with maximum in summer and minimum in f a l l and winter. Mammaria Cesati Mammaria echinobotryoides Ces. , Bot. Ztg. , 12_: 190, 1854. Colonies on PDA in different shades of gray to olivaceous black, effuse, with distinct wavy, flower-like zonation, darker in the center and lighter towards the margin; reverse gray to black in more or less the same f l o r a l design. Hyphae subhyaline to pale brown, 2-3.5 u thick. Conidiophores not readily differentiated from the vegetative hyphae, erect or repent, septate with dark, thick septa. Conidia of three types: (1) dominant dark conidia, pale to dark brown, ovoid, flame-shaped or short club-shaped, borne sessile or on short pedicels, single or in clusters, truncate at the base, often with dark thick ring (PI. V, f i g . 52, arrow) around the basal part where conidium detaching off, longitudinal germ s l i t often easily observed (PI. V, f i g . 53, arrow), (8-)10-14(-20) X 5-6.5 y. (2) arthroconidia (PI. V, f i g . 55) pale to dark brown, cylindrical to club-shaped in simple chain of 2-6 cells long; mostly 4-celled, usually breaking off as a unit and individual cells separated eventually, 3.5-7.0 y wide and variable in length. (3) phialoconidia (PI. V, f i g . 54) hyaline, forming a cluster at the tip of phialide, napiform, 2-3.5 X 1.8-2.5 y. Phialides (PI. V, figs. 56, 57) borne singly or in'groups, bottle-shaped, 9-12 X 3-4(-5) y, with distinct flare collarette of 1-1.5 y deep and 1.5-2.5 y wide. Hughes (1957) resurrected and described the genus Mammaria, 45 although the phialidic state was not reported by Hennebert u n t i l 1968. The presence of the Phialophbra state of Mammaria undoubtedly distinguishes i t from Echiriobotryum and Wardomyces with Scopulafiopsis state. Phialophora type conidia were not observed in any of the three M. echinobotryoides strains Hennebert (1968) studied on potato-glucose agar or malt agar at 28°C. I agree with him in not being able to find the phialoconidia in isolates on PDA plates incubated at 23°C. Later, in May, 1973, while transferring the stock cultures, I was surprised to find the Phialophora state in two one-year old M. echinobotryoides cultures kept at 5°C. As mentioned by Park (1973), phialoconidia were not as abundant as the other two types of conidia. One possible explanation for the delayed formation of phialoconidia in my isolates may be that the low storage temperature induced their formation. Park (1973) in his study of germina-tion of M. echinobotryoides spores also observed that dark conidia ("aleuriospores") were produced at temperatures ranging from 13°C to 25°C, however, phialoconidia and arthroconidia were observed only from 13°C to 20°C and not seen at a l l at 25°C. This coincides with the lack of phialoconidia reported by Sugiyama (1969) who incubated the fungus at 28°C, and also my observations of isolates incubated at 23°C. Mammaria was proposed as a monotypic genus. Batista j|t_ a l . (1961) added a second species, M. nectandrae Batista & Maia isolated from leaves of Nectandra sp. in Paraiba, Brazil. However, Sugiyama (1969) doubted i t s identification since the types of conidiophore and conidium development were quite different from that of M. echinobotryoides but similar to that of Rhinotrichum. Occurrence in Marion Lake: In this study, although with relative low density, M. echinobotryoides was one of the most widely distributed fungi and was isolated in a l l seasons. However, no seasonal fluctuation was detected. M. echinobotryoides has a world-wide distribution. It has been isolated on wood or from soils of Africa, Germany, Canada, Belgium, Japan and Nepal (Barron, 1968; Hennebert, 1968; Sugiyama, 1969). Metarrhizium Sorok. Metarrhizium anisopliae (Metsch.) Sorokin, Plant Parasites of Man and Animals, 1} 268, 1882. . The yellowish-green colonies and long conidial chains closely compacted into skyscraper-like columns (PI. IV, f i g . 46) made the i d e n t i f i -cation of this fungus relatively easy. Conidia (PI. IV, f i g . 47) hyaline to pale pigmented, cylindrical and slightly tapered to both ends, non-septate, 6-7.5 X 2-3 y, belonging to the small-spored strains. The large-spored strains of M. anisopliae measure 10-14 X 3-4 y. Occurrence in Marion Lake: Isolated once from Station 3, surface muds; October, 1972. M. anisopliae is known usually as an insect parasite causing "green muscardine", a disease having a world-wide distribution. Records from soils are relatively rare. Miller et a l . (1957) and Hodge (1962) reported i t from forest and cultivated soils of Georgia and Goos (1963) found i t in Honduras soils. Barron (1968) isolated i t from Ontario forest soils and regarded i t as "very common" there. 4 7 Myrotheclum Tode Myrotheeium sp. Occurrence in Marion Lake: Isolated once from Station 6 in February, 1 9 7 1 . Oedocephalum Preuss Oedocephalum spp. Occurrence in Marion Lake: Infrequent. Oidiodendron Robak Oidiodendron griseum Robak, Saertryck ur Svensk. Skogsvards-foreningens Tidsk., 3 / 4 : 4 4 0 , 1 9 3 4 . Colonies on PDA slow growing, powdery, greenish-gray to olivaceous brown. Conidiophores simple, dark brown at lower part; branching, hyaline, forming chains of conidia at upper part (PI. V, f i g . 5 8 ) , 1 . 5 - 2 . 5 y thick, up to 2 0 0 y long. Conidia (PI. V, f i g . 5 8 ) smooth, ovoid to ellipsoidal, 2 . 5 - 4 X 1 . 5 - 2 ( - 2 . 5 ) y. Occurrence in Marion Lake: Two isolates were assigned to this species. It appeared only in winter samples: October, 1 9 7 0 , Station 6 and December, 1 9 7 0 , Station 3 . 0_. griseum has been isolated from s o i l (Barron, 1 9 6 2 ) and frequently from pulp mills (Wang, 1 9 6 5 ) . Oidiodendron periconioides Morrall, Can. J. Bot., 4J>: 2 0 4 , figs. 1 - 4 , 1 0 - 1 2 , 1 9 6 8 . The isolates assigned to this species agree well with the original description of the type. It can be distinguished easily by the PLATE IV FIG. 35. Cylindrocarpon destructans. Conidiophores, phialides and macroconidia, X400. FIGS. 36, 37. C. didymum. Fig. 36. Macro- and micro-conidia, X1000. Fig. 37. Chlamydospores, X400. FIGS. 38, 39. Epicoccum purpurascens. Fig. 38. Conidiophores and young conidia, X1500. Fig. 39. Roughened mature conidia, showing ring-shaped basal c e l l (arrow r) and large scar (arrow s), X1000. FIG. 40. Geotrichum candidurn. Conidia in chains, phase contrast, X1000. FIGS. 41, 42. Gliocladium roseum. Fig. 41. Conidiophores, phialides and conidia, X400. Fig. 42. Conidial balls, X400. FIG. 43. G. virens. Conidiophores, phialides and conidia, X400. FIGS. 44, 45. (?)Humicola sp. Fig. 44. Dark conidia, X600. Fig. 45. Phialoconidia, phase contrast, X1000. FIGS. 46, 47. Metarrhizium anisopliae. Fig. 46. Conidial columns, X50. Fig. 47. Conidia, X1000. PLATE V FIGS. 48-51. Gliomastix murorum. Fig. 48. Phialides and conidia, X1000. Figs. 49-51. Conidial chains and conidial balls, Fig. 49, X100. Figs. 50, 51, X400. FIGS. 52-57. Mammaria echinobotryoides. Fig. 52. Conidiophore and dark conidia, showing thick basal ring (arrow), X1000. Fig. 53. Dark conidia, showing longitudinal germ s l i t (arrow), X400. Fig. 54. Phialoconidia, phase contrast, X400. Fig. 55. Arthroconidia in chains, X400. Figs. 56, 57. Phialides, showing distinct collarettes, X1000. FIG. 58. Oidiodendron griseum. Conidiophores and conidia, X1500. FIG. 59. 0. periconioides. Conidiophores and conidia with radiate-pattern walls, phase contrast, X1500. 51 P L A T E V characteristic thick conidial wall with the radiate pattern resulting from differences in optical densities (PI. V, f i g . 59). Occurrence in Marion Lake: _0. periconibides was distributed over the lake with the exception of Station 1, and was isolated only from August and October samples. Morrall (1968) isolated the fungus from Saskatchewan s o i l . This is probably the f i r s t report of fJ. pericoriioides since i t was described. Paecilomyces Bainier Paecilomyces carneus (Duche1 et Heim) Brown & Smith, Trans. Brit. Mycol. Soc., 40: 70, 1957. Occurrence in Marion Lake: Isolated once from Station 5, surface muds; October, 1970. Paecilomyces elegans (Corda) Mason & Hughes, apud Hughes, Mycol. pap., C.M.I., 45: 27, f i g . 6, 1951. The peculiar obliquely adhering conidia in long chains (PI. VI, f i g . 60) made this fungus easily recognizable. Conidia (PI. VI, f i g . 61) were ovoid to slightly fusoid, 5-6(-7) X 2.5-3(-3.5) y. Phialides (PI. VI, f i g . 61) were bottle-shaped, 12-20(-25) X 2^3.5 y. Colonies of my material were floccose, white to thin powdery and yellowish green at conidial areas. However, the coloration of the colony of P_. elegans was described as white, yellow, pink or pale buff by Brown and Smith (1957) in their monographic treatment of the genus. Occurrence in Marion Lake: P_. elegans was more common than P_. carneus in Marion Lake. It was distributed throughout the lake and showed a definite increase towards the winter. 53 P_. elegans i s considered as having a world-wide distribution and is isolated frequently from soils (Domsch and Gams, 1972). Paecilomyces griseovirides Onions & Barron, Mycol. pap., C.M.I., 107: 22, 1967. PI. VI, figs. 62, 63. This Marion Lake isolate agrees with Onions and Barron's original description except that the reduced phialides were not observed. The species is based on one isolate from Ontario s o i l . Its rare occurrence was attributed to the restricted growth of the fungus. Occurrence in Marion Lake: P_. griseovirides was found only once from Station 3 in September, 1971, not during the distributional and seasonal study. The type and the present finding are the only two reports of ]?. griseovirides from Canadian soils. As yet, this species has not been recorded from other parts of the world. Paecilomyces roseolus Smith, Trans. Brit. Mycol. Soc, 4^ 5: 388, 1962. My isolate agrees in a l l respects with the type described by Smith from dead stems of Dactylis sp.. Phialides (PI. VI, f i g . 64) of my material measured 3.2-3.5(-4) u at the base, narrowing towards the tip to 0.5-1 p thick and 18-25 y long. Conidia (PI. VI, f i g . 64) were lemon-shaped, smooth in long chains, (4-)5-6.5 X 3-3.5 u. Occurrence in Marion Lake: A single isolate represented this species in Marion Lake. It was isolated from surface muds of Station 5 in August, 1970 when plated on CZA. Besides this report of P_. roseolus from s o i l , de Bertoldi and Verona (1970) isolated i t from soils in Sardinia, Italy. 54 Paecilomyces terricola (Mill., Gidd. & Fost.) Onions & Barron, Mycol. pap., C.M.I., 107: 10, f i g . 3, 1967. Onions and Barron (1967) made this new combination for Fusidium  terricola M i l l . , Gidd. & Fost. as described by Miller j^t a l . (1957). Colonies on Czapek's agar floccose, loose textures, at f i r s t white, later flesh-colored with f i l i f o r m mycelium. Phialides (PI. VI, f i g . 65) simple, narrowed towards the tip , arising from procumbent or aerial hyphae, erect or procumbent, smooth, 10-33 X 2-2.5(-3) y. Conidia (PI. VI, figs. 66, 67) developing basipetally in very long, flexuous chains 70-100 y in length, fusiform with very acute ends, hyaline 3-6 X 1-1.5 y. The chains, as they age, become tangled masses and are very fungaceous. After examining a sub-culture from the type, Onions and Barron (1967) pointed out that the phialides were commonly 15-25 X 1.5-2 y, seldom as stout as 3 y as reported in the original description, and fusiform conidia were slightly flattened at one end and pointed at the other. The Marion Lake isolate agrees with that of Onions and Barron. Occurrence in Marion Lake: Despite i t s being generally considered as a "common" species, I?, terricola was isolated only once from Station 2, surface muds; October, 1970. This is believed to be the f i r s t report of F. terricola from Canadian s o i l . P_. terricola has a world-wide distribution; from United States, Congo, India, Egypt and Hong Kong (Domsch and Gams, 1972). Pestalotia de Not. Since i t was erected by de Notaris in 1839, Pestalotia has been a controversial genus. After several years of work, Guba (1961), wrote a comprehensive monograph on Pestalotia and Monochaetia. Steyaert (1949) 55 segregated and described two genera: Truncatella for 4-celled species; Pestalotiopsis for 5-celled species, while Pestalotia was limited only to i t s type P_. pezizoides de Not. and Moriochaetia was eliminated. Servazzi (1953), Guba (1955, 1956) and Dube and Bilgrami (1966) cr i t i c i z e d and dis-approved of Steyaert's proposal. In the present study, Guba's Pestalotia  sensu lato was followed and three species were assigned in the following paragraphs. Pestalotia spp. are known primarily as parasites of plants and are infrequently isolated from soils. Pestalotia monochaetioides Doyer, Med. Phytopath. Lab. "Will, Comm. Scholt.", 9: 24, 1925. Colonies on PDA floccose, buff to ochraceous gray, with dark acervuli. Conidia (PI. VI, f i g . 68) fusiform, 5-celled: two conical hyaline c e l l s , one at each end; and three intermediate coloured c e l l s in which two upper cells darker brown and one lower-cell pale brown. Setulae hyaline, mostly single, long, 40-60 X 1 u . Pedicels hyaline, simple or rarely branched, 8.5-14 X 1 u . Occurrence in Marion Lake: J?. monochaetioides was collected almost throughout the lake, i t s occurrence being limited to surface muds. The seasonal fluctuations of J?. monochaetioides, present in June, October and February; absent in August and December is striking. Due to the small size of the collection, a total of nine isolates, any explanation of this seasonal pattern i s impossible. Pestalotia truncata Lev., Ann. Sci., Nat. Bot., 3/5: 285, 1846. Colonies on PDA vinaceous buff to pale fawn, with black acervuli; reverse grayish ochraceous.. Conidia (PI. VII, f i g . 69) ellipsoidal, 18-25 X 5-6.5 u , 4-celled: two dark brown middle cells; one hyaline, round end PLATE VI FIGS. 60, 61. Paecilomyces elegans. Fig. 60. Conidial arrangement, X600. Fig. 61. Conidiophores, phialides and conidia, X400. FIGS. 62, 63. P_. griseovirides. Fig. 62. Simple phialides and conidia, X1000. Fig. 63. Conidia, X1000. FIG. 64. P_. roseolus. Phialides and conidia, X1000. FIGS. 65-67. P. terricola. Fig. 65. Phialides, phase contrast, X1000. Fig. 66. Conidial chains, X400. Fig. 67. Conidia, phase contrast, X1500. FIG. 68. Pestalotia monochaet io ides. Conidia, X600. 57 c e l l ; one conical hyaline c e l l bearing setulae at the other end. Setulae branched, hyaline, 10-20(-32) X 1 y:. Occurrence in Marion Lake: I?, truncata was collected once each from Stations 1, 2, 4 and as in the case of P_. monochaetibides confined to the surface muds. P_. truncata appeared s t r i c t l y in the winter season (December, 1970 and February, 1971). Bhatt (1965) also recorded a high frequency of Pestalotia from Ontario forest soils in the winter. While studying the fungal succession on the l i t t e r , Bradsberg (1969) and Tubaki and Yokoyama (1973) found i t only in the f a l l or winter. It seems logical to assume that the Marion Lake isolates of P. truncata are originally on the fallen leaves which are washed into the lake by the heavy winter r a i n f a l l . Probably i t can not survive the unfavourable conditions of the lake and eventually disappears. P_. truncata is the most common s o i l species of the genus, and has a world-wide distribution (Domsch and Gams, 1972). Pestalotia versicolor Speg., Michelia, J_: 479, 1879. Colonies on PDA rosy buff to apricot with black acervuli, aerial mycelium grayish white; reverse apricot to fulvous. Conidia (PI. VII, f i g . 70) fusiform or spindle-shaped, 25-35 X 8-10 y, 5-celled as in the manner of P_. monochaetioides. Setulae (PI. VII, f i g . 70) hyaline, 2-4; mostly 3, 20-40 y long. Pedicels hyaline, single, 8-10 y long. Occurrence in Marion Lake: With the exception of Station 4, P_. versicolor was isolated from the surface muds of the lake. In contrast with the J?. truncata, i t was mostly found in the summer, 1970. 59 Phialophora Medlar Since i t was erected by Medlar in 1915, with the type species P_. verrucosa Medlar, from a .chronic skin lesion of man, the genus Phialophora has been subjected to extensive investigation. Schol-Schwarz (1970) revised the genus to include those species having flask-shaped phialides with a collarette and one-celled slimy conidia. She also reduced the genus Margarinomyces Laxa to synonym with Phialophora. Most recently, Cole and Kendrick (1973) basing their conclusions on examination of cultures from wood-inhabiting species of Phialophora, proposed a new generic concept which emphasizes the formation of ampulliform to subulate phialides and well-defined collarettes and does not recognize those species producing chlamydospores. Moreover, Margarinomyces i s retained as a distinct genus by Cole and Kendrick. Phialophora (?)alba Beyma, Antonie van Leeuwenhoek, 9_: 57-58, 1943. Occurrence in Marion Lake: Rare. Phialophora fastigiata (Lagerb. & Melin) Conant, Mycologia, 2jh 598, 1937. Colonies on PDA velvet to floccose, olivaceous brown to black, aerial mycelium grayish brown, often forming hyphal ropes; reverse almost black. Phialides light brown, borne in clusters (PI. VII, f i g . 71) at tips of the lateral branches arising directly from hyphal strands or singly on hyphae (PI. VII, f i g . 72), with conspicuous collarettes average of 2 y deep, 6.5-10 X 2.5-3 y ' (excluding collarettes). Conidia (PI. VII, f i g . 71) ovoid to ellipsoidal, hyaline, forming slimy b a l l at the tip of phialide, 4.5-6 X IT.2.5 y. Occurrence in Marion Lake: P_. fastigiata was mainly isolated from surface 60 muds of Marion Lake. It showed a distinct preference for cold temperatures of December, 1970, and February, 1971. It had a lake-wide distribution when recorded. I?, fastigiata i s known as one of the causal organisms of blueing wood, and has a particular frequency from wood pulp (Robak, 1932; Melin and Nannfeldt, 1934; Wang, 1965). Brewer (1958, 1959) reported i t as the most widespread species of a l l the fungi isolated from slime in Newfoundland and New Brunswick paper mills and subsequently found i t common in mills of Quebec and Ontario. Records from s o i l are less common. However, high frequency of P_. fastigiata was recorded from Ontario forest soils (Bhatt, 1970). Phialophora sp. (C163, C295)* Colonies on PDA extremely slow growing, tough, elevated, buff to salmon, with white to pale pink aerial mycelium, funiculose. Phialides hyaline, borne singly on hyphae, variable in shapes: short urn-shaped (PI. VII, figs. 73, 74) or flask-shaped (PI. VII, f i g . 75) with slight constriction in the middle or long flask-shaped with upper part slightly broader than the lower part, (5-)6-7(-11) X 3-4(-5) .y excluding collarette. Collarettes (PI. VII, f i g . 75, arrow) conspicuous, slightly flared, 3-4 y deep and mostly 3 y wide. Conidia (PI. VII, f i g . 74) hyaline, ovoid, usually gathering in slimy b a l l at the tip of phialide, 2-3(-3.5) X 2-2.5 y. No existing species of Phialophora could properly accommodate this fungus. Until more authorities are consulted, the author is not ready to describe i t as a new fungus. Occurrence in Marion Lake: Infrequent.-Author's stock culture number. 61 Septonema Corda Septonema secedens Corda, Icon. Fung., 1: 9, 1837. Occurrence in Marion Lake: Isolated once in December, 1970 from Station 3. It is worthy of note that S_. secedens was collected one other time on decaying leaf of Acer sp. in the lake. Sporobolomyces Kluyver and van Niel Sporobolomyces sp. Occurrence in Marion Lake: Rare. Sporothrix Hektoen and Perkins Sporothrix sp. Occurrence in Marion Lake: Isolated once from Station 3; December, 1970. Thysanophora Kendrick The genus Thysanophora was created by Kendrick (1961) who described and illustrated T_. penicillioides (Roum.) Kendrick (basionym: Haplographium penicillioides Roum.) and T_. longispora Kendrick. Stolk and Hennebert (1968) proposed another new species, J:. canadensis Stolk & Hennebert from needles of Tsuga sp. and made a new combination, TT. taxi (Schneider) Stolk & Hennebert (basionym: Penicillium taxi Schneider). These four existing Thysanophora species form two distinct groups: 1\ penicillioides and JJ. longispora producing b i v e r t i c i l l a t e p e n i c i l l i and T. canadensis and T. taxi producing monoverticillate p e n i c i l l i . 62 Thysanophora penicillioides (Roum.) Kendrick, Can. J. Bot., _39: 820, 1961. PI. VII , figs. 77, 78. My material agrees with Kendrick's description. The measurements of conidiophores, metulae, phialides and conidia based on isolate C129 were as follows: conidiophores (4.5-)6-9(-14) y thick and up to 900 y t a l l ; metulae (10-)15-20 X (4-)5-6(-7) y; phialides (8-)10-12(-16) X 3-4 y; conidia 4-6.5 X 2-3.5 y. No sclerotia were detected. Occurrence in Marion Lake: T\ penicillioides was isolated more frequently from Station 5 than any other station. It was recorded only during cold seasons, from October, 1970 to February, 1971. TC. penicillioides, the most common species of the genus, has a cosmopolitan distribution. It i s associated particularly with the decaying conifer needles, such as Abies spp., Picea spp., Tsuga sp. and others (Kendrick, 1961; Barron, 1968; Sutton, 1973), although Tubaki and Yokoyama (1971) have recorded i t on leaves of Castanopsis cuspidata Schottky during the early to middle processes of decay. Subsequently, Tubaki (1973) noted i t s preference to the cooler areas of Japan. Records of this species from soils are relatively rare, although i t is not uncommon in soils of Ontario cedar forests (Bhatt, 1970). Torulomyces Delitsch Until f a i r l y recently the genus MonocilHum Saksena was retained as distinct from Torulomyces, not withstanding Barron's (1967, 1968) con-firmation that T_. lagena Delitsch and M. humicola Barron were conspecific. Barron's uncertainty of Monocillium being congeneric with Torulomyces was because the conidium ontogeny in M. indicum Saksena, type species of the 63 genus Monocillium, was not clear at that time. However, Hashmi et a l . (1972), based on time-lapse observations of conidium ontogeny and karyology of conidiogenesis of T_. lagena and M. indicum, proved these two genera congeneric. Accordingly, M. indicum was transferred to Torulomyces. Torulomyces lagena Delitsch, Systematik der Schimmel Pilze, Druck J. Neudamm, Germany : 91, 1943. Colonies on PDA slow growing fawn to mouse gray, often with white sectors, wrinkled with radiating grooves, narrowly zonate towards the margin. Conidiophores simple, hyaline, borne directly on vegetative hyphae, basal stalk, 3-6 X 1 y; swollen at apex forming a vesicle (?phialide) being delimited by a septum from basal stalk, then tapering to a short neck, 2-3 y broad at the widest part and 3-5 y long. Conidia spherical in long chains with narrow connectives between conidia (PI. VII, f i g . 76), smooth becoming roughened in age, 1.5-2.5 y in diameter. Occurrence in Marion Lake: T_. lagena was found in Stations 2, 3 and 4, and more or less equally abundant in surface and lower sediments. It was totally absent in October and December, 1970. T_. lagena has a world-wide distribution (Barron, 1968). It was isolated with high frequency from Ontario forest soils (Bhatt, 1970). Dickinson and Dooley (1969) reported i t s presence fronCIrish peat bogs. Trichocladium Harz Trichocladium opacum (Corda) Hughes, Trans. Brit. Mycol. Soc, 35: 154, 1952. PI. VII, f i g . 79. My material agrees very well with the description given by Hughes 64 (1952) and Kendrick and Bhatt (1966). Occurrence in Marion Lake: It was isolated s t r i c t l y from surface muds of Stations 2 and 3, in August and December, 1970, and February, 1971. The distribution of T_. opacum is world-wide. Reports of i t s occurrence were list e d in detail by Domsch and Gams (1972). In addition, Bhatt (1970) found i t common in Ontario forest soils; Matsushima (1971) recorded i t from Papua-New Guinea s o i l ; Sutton (1973) collected i t on Acer sp. from Saskatchewan. Trichoderma Pers. ex Fr. The excellent monographic treatment of the genus Trichoderma Pers. ex Fr. by Ri f a i (1969) was followed essentially for specific identification of the isolates of Trichoderma from Marion Lake sediments. R i f a i proposed "the concept of species aggregate—an entity which can be defined as aggre-gations of morphologically very similar and often hardly separable species", and recognized nine species aggregates of Trichoderma. They were T_. piluliferum Webster & R i f a i , _T. polysporum (Link ex Pers.) Ri f a i , _T. hamatum (Bon.) Bain., _T. koningii Oud., T_. aureoviride Ri f a i , _T. harzianum Ri f a i , _T. longibrachiatum R i f a i , T_. pseudokoningii R i f a i , and TC. viride. Hammill (1970) added another new species, T_. saturnisporum Hammill from forest soils of Georgia. Trichoderma hamatum (Bon.) Bain. aggr. sensu Rifai, Mycol. pap., C.M.I., 116: 22-31, figs. 6-9, 1969. The Marion Lake isolates agree well with the general description of _T. hamatum by Ri f a i . The compactly tufted, whitish-green conidial cushions of colony due to the presence of s t e r i l e hyphal elongations of conidio-phores (PI. VIII, f i g . 80) and short, plump, and crowded phialides PLATE VII FIG. 69. Pestalotia truncata. Conidia, X400. FIG. 70. P. versicolor. Conidia, X400. FIGS. 71, 72. Phialophora fastigiata. Fig. 71. Phialides in clusters and conidia, X1000. Fig. 72. Single phialide borne on hypha, X1000. FIGS. 73-75. Phialophora sp. Figs. 73, 74. Urn-shaped phialides, X1500. Fig. 75. Flask-shaped phialides, showing collarette (arrow) and conidia, X1000. FIG. 76. Torulomyces lagena. Conidiophores and conidia in chains, showing narrow connections between conidia, phase contrast, X1000. FIGS. 77, 78. Thysanophora penicillioides. Fig. 77. Apical penicillate heads, showing narrow-necked phialides, X1000. Fig. 78. Conidium, X1500. FIG. 79. Trichocladium opacum. Conidiophores and conidia, X400. 67 (PI. VIII, f i g . 81) distinguish this species aggregate from the others. Conidia (PI. VIII, f i g . 81) are oblong or ellipsoidal and measure 3.5-5.2(-6.5) X 2.1-2.8(-3.0) u. Occurrence in Marion Lake: T\ hamatum was one of the common species isolated from Marion Lake. It was recorded throughout the lake, mainly in the surface muds and was isolated throughout the year, particularly abundant in the winter. Domsch and Gams (1972) noted that T_. hamatum often has been con-fused with T_. koningii. The former differs from the latter in having much stouter phialides and the presence of ste r i l e hyphal elongations. Although records of T_. hamatum are not so numerous as those of T. koningii, the dis-tribution of T.. hamatum is world-wide. Trichoderma hamatum (Bon.) Bain. aggr. sensu Ri f a i (NS) The conidiophores, the size, shape and disposition of the phialides and the characters of phialospores of these Marion Lake isolates resemble that of J:. hamatum described by Ri f a i . It differs from the latter in the absence of sterile hyphal elongations, and consequently in much greener colonies. R i f a i observed that there was a continuous series showing reduc-tion of development of sterile hyphal elongations of the isolates he studied and doubted the taxonomic value of these st e r i l e elongations. The absence of the sterile hyphal elongation in the Marion Lake isolates is so constant that "NS" (no ste r i l e hyphal elongation) is appended to distinguish them from those isolates with characteristic hyphal elongations. Occurrence in Marion Lake: T_. hamatum (NS) was most abundant in f a l l and late winter and was equally distributed throughout the lake. 68 Trichoderma koningii Oud. aggr. sensu Rifai. Mycol. pap., C.M.I., 116: 31-34, figs. 10-11, 1969. PI. VIII, figs. 82, 83. Occurrence in Marion Lake: T_. koningii was well distributed throughout the lake, particularly abundant in the surface muds. More isolates were recorded in the winter. Trichoderma polysporum Link ex Pers. aggr. sensu Rifai. Mycol. pap., CM.I., 116: 18-22, f i g . 5, 1969. This fungus is characterized by watery-white colonies, tufted conidiophores forming compact mats, and sterile hyphal elongations of the conidiophores (PI. VIII, f i g . 85). The phialides (PI. VIII, f i g . 86) are short and plump, 4-7.0(-10.0) X 3-3.5(-4.0) u. The conidia are in slimy heads at the tips of the phialides, ovoid to ellipsoidal, smooth-walled, 2.8-3.8(-4.2) X 1.8-2.0(-2.5) y (PI. VIII, f i g . 84). Occurrence in Marion Lake: T_. polysporum was found throughout the year, although more abundant in f a l l and winter, and was distributed throughout the lake, although less frequent at Station 5. T_. polysporum is quite common in the s o i l and wide-spread through-out the world (Rifai, 1969; Domsch and Gams, 1972). Trichoderma saturnisporum Hammill, Mycologia, bl\ 112, figs. 8-10, 1970. PI. VIII, figs. 87, 88. The Marion Lake material agrees well with the original description of the type material which was isolated from forest s o i l in Georgia. As noted by Hammill, the membranous, wing-like appendages surrounding the conidia (PI. VIII, f i g . 87) make this species easily recognized. 69 Occurrence in Marion Lake: A total of six isolates from Stations 2, 3, 5 and 6 were recorded. It was absent in June, 1970. As far as I am aware, this i s the f i r s t report of T^. saturnisporum since i t was described. Trichoderma viride Pers. ex Gray aggr. sensu Ri f a i , Mycol. pap., C.M.I., 116: 47-53, figs. 17-19, 1969. T_. viride is characterized by i t s rough-walled conidia (PI. VIII, f i g . 89). Most conidiaar.e globose or short obovoid. Occurrence in Marion Lake: T_. viride was one of the most common fungi in Marion Lake sediments. Although a slight increase in the numbers of isolates was recorded in early winter, i t was isolated a l l year round. As to the spatial distribution, i t showed a lake-wide distribution with a tendency of increasing numbers of isolates towards the center of the lake, i.e., from Station 1 to Station 2 to Station 3. T_. viride was more abun-dant in the surface muds. The information on ecology and physiology has been well compiled by Domsch and Gams (1972). It is well-known that T_. viride i s one of the most widely spread s o i l fungi, and mostly abundant in acidic soils (Warcup, 1951; Sewell, 1959a; Pugh, 1960; Parkinson and Balasooriya, 1967). Umbelopsis Amos & Barnett Umbelopsis versiformis Amos & Barnett, Mycologia, j>8: 807, 1966. PI. IX, figs. 90, 91. The Marion Lake material agrees in a l l respects with the original description of the type material which was obtained from roots of Quercus  borealis Michx. in eastern West Virginia. Occurrence in Marion Lake: U. versiformis was recovered throughout the lake PLATE VIII FIGS. 80, 81. Trichoderma hamatum. Fi g . 80. S t e r i l e hyphal elongations, X400. Fig . 81. Conidiophores, phialides and conidia, X1000. FIGS. 82, 83. T. k o n i n g i i . F i g . 82. Conidiophores and ph i a l i d e s , X1000. Fig . 83. Conidia, X1000. FIGS. 84-86. T. polysporum. F i g . 84. Conidia, X1000. Fig . 85. Conidiophores, showing s t e r i l e hyphal elongation, X600. Fi g . 86. Conidiophores, phialides and conidia, X1000. FIGS. 87, 88. T. saturnisporum. F i g . 87. Conidia, showing membranous, wing-like appendages, X1000. Fig . 88. Conidiophores, phi a l i d e s and conidia, X400. FIG. 89. T. v i r i d e . Conidia, X1000. 72 except Station 4 and was isolated a l l year round; most abundant in June, 1970. Amos and Barnett also isolated U. versiformis from roots of oak, maple and poplar and from s o i l near oak trees. Barron (1968) reported this monotypic genus from Ontario forest soils twice. Since then, U. versiformis apparently has not been recorded in any part of the world. Ver t i c i c l a d i e l l a Hughes Verti c i c l a d i e l l a procera Kendrick, Can. J. Bot., 40: 783-786, 1962. PI. IX, figs. 94-97. The Marion Lake material assigned to this species differs slightly from that originally described. Conidia are broader, 2-3 y wide, than the type, which measure 1.3-1.8(-2.2) y. Occurrence in Marion Lake: Isolated from Stations 1, 4 and 5; August, October, 1970, and February, 1971; more common in October, 1970. Barron (1968) pointed out that the d i f f i c u l t i e s of examining the conidiogenous c e l l s may result in misidentifying i t as one of morphologi-cally similar members of Leptographium complex. So i t s actual occurrence in s o i l is unknown. However, isolates of Ve r t i c i c l a d i e l l a species were obtained by Barron from organic soils of peat bogs in Ontario. Verticillium Nees Verticillium state of Nectria inventa Pethybr., Trans. Brit. Mycol. Soc, 6: 107, 1919. PI. IX, figs. 92, 93. The brick red colour of colonies, reddish brown conidiophores and PLATE IX FIGS. 90, 91. Umbelopsis v e r s i f o r m l s . Conidiophores and c o n i d i a , X400. FIGS. 92, 93. V e r t i c i l l i u m s t a t e of N e c t r i a inventa. F i g . 92. Conidiophores and c o n i d i a l b a l l s , X400. F i g . 93. Conidiophores, showing v e r t i c i l l a t e p h i a l i d e s and c o n i d i a , X400. FIGS. 94-97. V e r t i c i c l a d i e l l a procera. F i g . 94. Conidiophores with c o n i d i a gathering i n b a l l s , X50. F i g . 95. Conidiophores, showing r h i z o i d a l hyphae at the basal p o r t i o n s of the s t i p e s , X150. F i g s . 96, 97. A p i c a l p o r t i o n s of conidiophores, showing sympodulae and c o n i d i a , phase c o n t r a s t , X1500. 74 PLATE IX 75 v e r t i c i l l a t e l y arranged phialides make this fungus easily distinguishable. Detailed description, illustration and discussion in nomenclature can be found in Hughes (1951). Occurrence in Marion Lake: This fungus was isolated three times from Marion Lake: in October, 1970, one isolate each from Stations 4 and 5; in February, 1971, from Station 3. It has a world-wide distribution; from various soils or on decaying plant remains. Ver t i c i l l ium (?)terrestre (Link) Lindau, Kryptog. FI., 1_: 320, 1970. Occurrence in Marion Lake: Infrequent. 76 ENVIRONMENTAL FACTORS Ranges and means of organic matter (%) , pH and temperature recorded for the sediments, together with the number of viable propagules per gram of dry sediment counted over the study period are presented in Table I. The complete data can be seen in Appendix I. Organic Matter — The seasonal variation in the percentage of organic matter of the sediment i s graphically illustrated in Figures 2 and 3. The organic matter levels were found to fluctuate throughout the year. The results show that the surface sediments (Section I) contained only slightly higher organic matter, ranging from 25.5 - 31.2%, than the lower sediments (Section II), ranging from 24.1 - 30.0%. In general, Station 6 was the lowest in organic matter, while Stations 3 and 4 were the highest. Figure 2 reveals that the organic matter of the sediments of Stations 3, 4 and 5 fluctuated in the same pattern: decreased from June to October, then increased in December, followed by a drop in February, and once again reached a high peak in April. At Station 6, the general fluctuation of organic matter showed the same trend as that of Stations 3, 4 and 5, except for the increase from August to October. At Stations 1 and 2, the seasonal variation of organic matter was less pronounced and, in contrast to the other stations, the lowest organic matter percentage occurred in December. Organic matter percentage of the lower sediments at Stations 1, 2, 4 and 6 followed more or less the same fluctuation as that of the surface sediments. However, slight variation was noticed at Stations 3 and 5. At Station 3, October was the month of highest percentage of organic matter in the lower sediments instead of being the lowest in organic matter as in the case of the surface sediments. pH — pH values recorded during the study period ranged from 5.4 - 7.2, TABLE I SEDIMENT CHARACTERISTICS AND NUMBERS OF FUNGI PER GRAM OF DRY SEDIMENT AT EACH OF SIX MARION LAKE SAMPLING STATIONS, JUNE, 1970 TO APRIL, 1971* (MEANS IN PARENTHESES) Station Section Organic Matter (%) pH Temperature (°C) Fungal Numbers (XlO 3) I 26.5-28.5 (27.7) 6.0-6.3 2.0-7.8 (5.2) 18.93-49.80 (34.98) 1 II 26.3-28.1 (27.1) 5.8-6.1 2.0-7.8 (5.1) 8.12-16.67 (11.98) I 28.0-29.8 (28.7) 5.4-6.4 2.0-7.8 (5.0) 29.76-43.88 (36.74) 2 II 26.8-28.3 (27.5) 5.5-6.1 2.0-8.1 (5.0) 6.50-22.04 (14.70) I 27.3-30.8 (29.2) 5.4-6.4 2.0-7.8 (4.7) 31.48-63.51 (40.08) 3 II 25.4-27.2 (26.4) 5.6-5.8 2.0-7.8 (4.6) 9.80-15.32 (12.68) I 27.6-31.2 (29.7) 5.7-6.2 2.0-7.8 (5.1) 24.74-44.22 (32.73) 4 II 25.7-30.0 (28.0) 5.8-7.2 2.0-7.8 (5.0) 6.76-12.84 (10.07) I 26.7-31.1 (28.9) 5.9-6.4 2.0-7.8 (4.9) 25.88-54.20 (35.98) 5 II 24.8-28.4 (26.5) 5.9-6.6 2.0-7.8 (4.8) 9.67-16.93 (12.77) I 25.5-28.8 (27.0) 5.8-6.2 2.0-7.8 (5.1) 17.97-61.73 (37.88) 6 II 24.1-26.5 (25.4) 6.2-6.8 2.0-7.8 (5.1) 5.49-14.76 (10.72) pH and temperature of June and August, 1970 were not recorded. FIGURE 2 Seasonal variation in organic matter content (%), Marion Lake surface sediments (Section I). Stations 1 • — — — — FIGURE 2 32_ FIGURE 3 Seasonal v a r i a t i o n i n organic matter content(%), Marion Lake lower sediments (Section I I ) . See Figure 2 for explanation of symbols. FIGURE 3 J U N A U G OCT DEC FEB A P R 1 9 7 0 1971 82 with most samples being slightly acid. The results showed a gradual increase in acidity from October to February, perhaps resulting from the leaf f a l l . They also indicated that the greatest variation between stations occurred in February and April. The lowest pH value was recorded at Station 3. Temperature — The recorded temperatures followed the expected annual changes, with the coldest temperature in February. The lowest temperature was recorded at Station 3. Only slight variation in temperature was observed between stations. It was noticed also that in both October and February, the mud temperature was identical throughout the lake being 7.8°C and 2.0°C respectively, with the exception of Station 2 in October which was 8.1°C for the lower sediments and Station 6 in February which showed a temperature of 2.4 - 2.8°C. Attempts to correlate the seasonal variation in the total numbers of viable fungus propagules with the above mentioned environmental factors, viz., organic matter (%), pH and temperature, have proved inconclusive. ISOLATION MEDIUM The total numbers of fungal isolates from plating the sediments on CZA and 2% MA during the present study are summarized in Table II. The data show that most of the fungi, 56 species and species groups out of a total of 79, were isolated on both types of media, although differences in frequency were observed. Aureobasidium bolleyi, Beauveria bassiana, Cephalosporium khandalense, Cephalosporium spp., Chloridium chlamydosporis, Cladosporium cladosporioides, fj. herbarum, Paecilomyces elegans, Pestalotia versicolor and Phialophora fastigiata were isolated most fre-quently on CZA; while Botrytis cinerea, Cephalosporium incarnatum var. macrosporum, Oidiodendron pericbnioides, Thysanophora penicillioides, TABLE II FUNGI AND THEIR NUMBERS OF ISOLATES ON CZAPEK SOLUTION AGAR AND/OR 2% MALT AGAR ISOLATED FROM MARION LAKE SEDIMENTS ON BOTH MEDIA CZA 2% MA Aureobasidium bolleyi 11 4 A. pullulans 1 3 Beauveria bassiana 11 6 Botrytis cinerea 1 5 Candida sp. 1 1 Cephalosporium acremonium 30 23 C. incarnatum 4 3 C. incarnatum var. macrosporum 7 14 C. khandalense 10 2 Cephalosporium spp. 8 4 Chloridium chlamydosporis 10 2 Cladosporium cladosporioides 10 3 C. herbarum 15 6 Cylindrocarpon destructans 9 8 C. (?)lucidum 1 1 Geniculosporium serpens 2 1 Geotrichum candidum 21 12 Gliocladium roseum 8 8 G. virens 6 8 Gliocladium spp. 1 3 Gliomastix murorum 2 1 Gliomastix spp. 2 1 (?)Humicola sp. 244 197 Mammaria echinobotryoides 9 7 Oedocephalum spp. 6 6 Oidiodendron griseum 1 1 0. periconioides 1 5 Paecilomyces elegans 25 8 Paecilomyces spp. 1 1 Penicillium spp. 184 191 Periconiella sp. 1 1 Pestalotia truncata 1 1 P. versicolor 5 1 Phialophora fastigiata 10 5 Phialophora spp. 6 5 Thysanophora penicillioides 3 7 Torulomyces lagena 2 3 Trichocladium opacum 3 1 Trichoderma hamatum 57 65 T. hamatum (NS) 34 19 T. koningii 19 18 T. polysporum 62 59 T. saturnisporum 4 2 T. viride 104 140 TABLE II —Continued CZA 2% MA Trichoderma spp. 31 20 Umbelopsis versiformis 18 17 Verticicladiella procera 1 4 Verticillium (?)terrestre 3 3 Hyaline Mycelia S t e r i l i a 120 105 Dark Mycelia S t e r i l i a 112 87 Mortierella isabellina 1 1 M. vinacea 11 14 Mucor spp. 13 13 Anixiopsis sp. 2 15 Coniothyrium spp. 2 3 Pseudoeurotium zonatum 2 9 ON CZA ONLY Alternaria alternata 1 Cephalosporium iricoloratum 2 Cladosporium macrocarpum 1 Cordana pauciseptata 1 Cylindrocarpon didymum 5 Gliocladium catenulatum 6 Myrothecium sp. 1 Paecilomyces roseolus 1 P. terricola 1 Pestalotia monochaetioides 9 Phialophora sp. 3 Septonema secedens 1 Sporothrix sp. 1 Emericellopsis terricola 1 ON 2% MA ONLY (?)Acrogenospora state of Farlowiella carmichaeliana 1 Arthrinium sacchari 1 Aspergillus spp. 4 Chrysosporium pannorum 1 Cladosporium musae 1 Metarrhizium anisopliae 1 Paecilomyces carneus 1 Sporobolomyces sp. 2 Verticillium state of Nectria inventa 3 85 Verti c i c l a d i e l l a procera and the two Ascomycetes: Anixiopsis sp. and Pseudoeurotium zonatum van Beyma were most frequently isolated on.2% MA. So far as the dominant species were concerned, e.g. (?)Humic6la sp., Penicillium spp., Trichoderma hamatum, T_. koningii, T^. polysporum, T\ viride and hyaline and dark Mycelia S t e r i l i a , there were no significant differences between the two media. As indicated in Table II, some fungal species or species groups were isolated only on CZA or on 2% MA, most of these having a very low isolation frequency. This may just be an indication of chance isolation. However, Cylindrocarpon didymum, Gliocladium catenulatum, Pestalotia  monochaetioides and Phialophora sp. were recorded on CZA and Aspergillus spp. and Verticillium state of Nectria inventa on 2% MA only. COMPARISON OF INCUBATION TEMPERATURES: 5°C AND 25°C FOR ISOLATION OF FUNGI Table III l i s t s the fungi and their numbers of isolates recorded at 5°C and 25°C incubation from Marion Lake sediment samples collected April, 1971 at Station 3. The low incubation temperature (5°C) slowed down the fungal development so that the incubation period was extended to six weeks. An examination of the results indicated that not only more fungal species but also more colonies were isolated at 25°C than 5°C. The number of colonies of the heavily sporing species, for example, Penicillium spp. and Trichoderma viride was reduced by incubating under low temperature and i t accounted for 30% of the total colony increase at 25°C. However, the isolation of these fungi was not affected much by the incubation tempera-tures. No Trichoderma hamatum was obtained at 5°C. It was noticed also that high and low temperatures favoured the recovery of hyaline and dark ste r i l e mycelia respectively. TABLE I II NUMBERS OF ISOLATES RECORDED AT 5°C (6 WEEKS) AND 25°C (6 DAYS) FROM MARION LAKE SEDIMENTS, STATION 3 Fungi Isolated Temperature Incubated 5°C 25°C Aureobasidium b o l l e y i 1 1 A. pullulans - 2 Beauveria bassiana 2 2 Cephalosporium acremonium 4 3 C. incarnatum var. macrosporum - 1 C. khandalense 3 4 Cephalosporium spp. - 2 Chloridium chlamydosporis - 1 Cordana pauciseptata - 1 Cylindrocarpon destructans 2 5 Epicoccum purpurascens 1 -Geotrichum candidum 3 Gliocladium roseum - 3 (?)Humicola sp. 30 33 Mammaria echinobotryoides - 2 Oidiodendron tenuissimum - 1 Paecilomyces elegans - 5 P e n i c i l l i u m spp. 10 22 P e s t a l o t i a truncata 1 P. v e r s i c o l o r 1 1 Phialophora (?)alba 1 P. f a s t i g i a t a 2 3 Phialophora spp. 2 1 Thysanophora p e n i c i l l i o i d e s - 1 Trichocladium opacum 1 1 Trichoderma hamatum - 7 T. hamatum (NS) 1 5 T. k o n i n g i i - 3 T. polysporum 7 8 T. v i r i d e 12 19 Umbelopsis versiformis 1 5 V e r t i c i l l i u m ( ? ) t e r r e s t r e - 2 Hyaline Mycelia S t e r i l i a 11 30 Dark Mycelia S t e r i l i a 33 14 Unidentified —12 - 1 M o r t i e r e l l a vinacea - 3 Mucor spp. 2 Coniothyrium spp. - 1 Pseudoeurotium zonatum 1 2 Number of species and species groups i s o l a t e d 23 34 Number of species and species groups i s o l a t e d at both temperatures 18 Number of i s o l a t e s 132 195 87 SEASONAL AND SPATIAL VARIATIONS Before presenting the results of my study of the occurrence, dis-tribution and seasonal fluctuation of Hyphomycetes in Marion Lake sediments, I should note that (a) Station 4 was not established at the f i r s t sampling date (June, 1970); (b) sediment samples of Station 5 collected in December, 1970 could not be analyzed due to technical failure; (c) only the fungal counts of the April, 1971 sediment samples were made but no isolation or identifications were carried out. Since the number of samples collected at bimonthly interval varies from five to six the comparison of data w i l l be based on mean values. Seasonal Variation Seasonal variation of viable propagules of sediment is illustrated in Figures 4 arid 5. The mean number of species and species groups isolated is presented also in Figure 4. Comparisons show obviously that the viable counts of surface sediments (Section I) were consistently higher than that of lower sediments (Section II), ranging from approximately 18.0 - 63.5 X 3 3 10 /g dry sediment for the former and 5.5 - 22.0 X 10 /g dry sediment for the latter. The graphs also show that seasonal fluctuation was particularly noticeable in surface sediments, whereas i t was less regularly character-i s t i c of lower sediments. Thus, only the seasonal variation of viable counts of the surface sediments i s discussed in detail in the following paragraphs. In general, the maximum fungal counts occurred during December and/or February at the six stations. Both Stations 3 and 6 had their high-3 3 est peaks in December, reaching 63.5 X 10 and 61.7 X 10 /g dry sediment respectively; at Stations 1 and 2, the greatest number was recorded in 3 December and extended through February, reaching 48.8 X 10 and 3 43.9 X 10 /g dry sediment respectively; Station 4 showed i t s maximum FIGURE 4 Seasonal v a r i a t i o n of v i a b l e fungal propagules per gram of dry surface sediment (Section I) from Marion Lake stations (Log scale) and mean number of species and species groups per s t a t i o n . See Figure 2 for explanation of symbols. 89 FIGURE 4 100000 SECTION I z I D O CJ LU _J C D < > 10000 5 0 0 0 \ 0 JUN AUG OCT DEC 1970 MONTHS — I , — FEB APR 1971 2 m > p O ~H 112 co m O m oo P° tn ~a m L8 G m co .11 ..10 .9 7 az TJ LO FIGURE 5 Seasonal variation of viable fungal propagules per gram of dry lower sediment (Section II) from Marion Lake stations (Log scale). See Figure 2 for explanation of symbols. 91 FIGURE 5 92 3 of 44.2 X 10 /g dry sediment in February. With the exception of Station 5, the fungal counts increased gradually from June, August to October. A slight drop in count was observed at Station 3 in October. After reaching their maxima, a significant decrease at Stations 3 and 6 was recorded in February. However, this drop was not exhibited at Stations 1 and 2 u n t i l April. Generally, the minimum fungal counts were observed in June. Figure 4 also indicates that the fluctuation of the total isolations in the surface muds was accompanied by a similar variation in the mean number of species and species groups isolated during the investigation. That i s , there was a gradual increase in the number of species and species groups isolated in June, August, October and December, then followed by a drop in February. Absolute season density (percentage of total isolates from each season) and the actual numbers of isolates of fungi from Marion Lake sediments are compiled in Appendix III. Presence or absence of Hyphomycetes with their absolute density (percentage of total isolates) and percentage frequency of seasonal occurrence (percentage of seasonal collections showing positive recordings) which are derived from Appendix III, are presented in Table IV. The seasonal fluctuations of a number of species.also, are'diagram-matically shown in Figures 6-11. The data show that eighteen species and species groups were isolated throughout the year. These were: (?)Humicola sp., Penicillium spp., Trichoderma viride, Hyaline and Dark Mycelia S t e r i l i a , T_. hamatum, T\ polysporum, Cephalosporium acremonium, T\ hamatum(NS), Trichoderma spp., Umbelopsis versiformis, C_. incarnatum var. macrosporum, Beauveria bassiana, Gliocladium roseum, Mammaria echinobotryoides, Aureobasidium bolleyi, Chloridium chlamydosporis and Cephalosporium incarnatum. However, different SEASONAL DISTRIBUTION FUNGAL NAMES JUN AUG 1970 (?)Humicola sp. + + Penicillium spp. + + Trichoderma viride + + Hyaline Mycelia S t e r i l i a + + Dark Mycelia S t e r i l i a + + Trichoderma hamatum + + Trichoderma polysporum + + Cephalosporium acremonium + + Trichoderma hamatum (NS) + + Trichoderma spp. + + Umbelopsis versiformis + + Cephalosporium incarnatum var. macrosporum + + Beauveria bassiana + + Gliocladium roseum + + Mammaria echinobotryoides + + Aureobasidium bolleyi + + Chloridium chlamydosporis + + Cephalosporium incarnatum + + Trichoderma saturnisporum - + Trichoderma koningii - + Oedocephalum spp. - + Geotrichum candidum - + Cephalosporium spp. - + Cylindrocarpon destructans - + Paecilomyces elegans - + Torulomyces lagena + + Aspergillus spp. + + TABLE IV HYPHOMYCETES FROM MARION LAKE SEDIMENTS OCT DEC FEB ABSOLUTE % FREQUENCY OF 1971 DENSITY SEASONAL OCCURRENCE + + + 17.38 100 + + + 14.78 100 + + + 9.61 100 + + + 8.86 100 + + + 7.84 100 + + + 4.80 100 + + + 4.76 100 + + + 2.08 100 + + + 2.08 100 + + + 2.01 100 + + + 1.37 100 + + + 0.82 100 + + + 0.67 100 + +• + 0.63 100 + + + 0 . 6 3 100 + + + 0.59 100 + + + 0.47 100 + + + 0.27 100 + + + 0.23 80 + + + 1.45 80 + + + 0.47 80 + + + 1.34 80 + + + 0.47 80 + + + 0.70 80 • + + + 1.30 80 + 0.19 60 + 0.15 60 TABLE IV —Continued FUNGAL NAMES JUN AUG OCT DEC FEB ABSOLUTE % FREQUENCY OF 1970 1971 DENSITY SEASONAL OCCURRENCE Pestalotia monochaetioides + - + - + 0. 35 60 Unidentified—12 - + + - + 0. 27 60 Vert i c i c l a d i e l l a procera - + + - + 0. 19 60 Phialophora fastigiata - + - + + 0. 59 60 Gliomastix murorum - + - + + 0. 11 60 Trichocladium opacum - + - + + 0. 15 60 Botrytis cinerea - + - + + 0. 23 60 Cladosporium herbarum - - + + + 0. 86 60 Thysanophora penicillioides - - + + + 0. 39 60 Verticillium (?)terrestre - - + + + 0. 23 60 Phialophora spp. - - + + + 0. 43 60 Gliomastix spp. - - + + + 0. 11 60 Cephalosporium khandalense - - + + 0. 47 60 Geniculosporium serpens + + - - — 0. 11 40 Gliocladium virens + - + - - 0. 55 40 Pestalotia versicolor + - - + - 0. 23 40 Coniothyrium sp. + - - - + 0. 19 40 Sporobolomyces sp. + - - - + 0. 07 40 Didiodendron periconioides - . + + — — 0. 23 40 Paecilomyces spp. - + + - — • 0. 07 40 Aureobasidium pullulans - + - + - 0. 15 40 Oidiodendron griseum - - + + - 0. 07 40 Cylindrocarpon didymum - - + + - 0. 19 40 Gliocladium spp. — — + — + 0. 15 40 Verticillium state of Nectria Inventa - - + - + 0. 11 40 Cephalosporium incoloratum - - — + + 0. 07 40 Pestalotia truncata - - - + + 0. 11 40 Cladosporium cladosporioides - - - + + 0. 59 40 Paecilomyces roseolus — + — — — 0. 03 20 TABLE IV FUNGAL NAMES JUN AUG OCT 1970 Cladosporium musae - + -Alternaria alternata + Gliocladium catenulatum - - + Metarrhizium anisopliae + (?)Acrogenospora state of Farlowiella carmichaeliana - - + Paecilomyces terricola + Paecilomyces carneus - - + Chrysosporium pannorum - - + Cordana pauciseptata Septonema secedens Phialophora sp. Cladosporium macrocarpum Sporothrix sp. Cylindrocarpon (?)lucidum Periconiella sp. Arthrinium sacchari Candida sp. Total number of species 26 39 48 Number of stations collected 5 6 6 Average number of species per station 5.2 6.5 8.0 + = present - = absent -Continued DEC FEB ABSOLUTE % FREQUENCY OF 1971 DENSITY SEASONAL OCCURRENCE 0.03 0.03 0.23 0.03 20 20 20 20 0.03 20 0.03 20 0.03 20 0.03 20 + - 0.03 20 + - 0.03 20 + - 0.11 20 + - 0.03 20 + - 0.03 20 + 0.07 20 + 0.07 20 + 0.03 20 + 0.07 20 47 51 5 6 9.4 8.5 Ln FIGURE 6 Seasonal v a r i a t i o n - number of i s o l a t e s of (?)Humicola sp., P e n i c i l l i u m spp., Trichoderma v i r i d e , Hyaline Mycelia S t e r i l i a , Dark Mycelia S t e r i l i a , T. hamatum and T^ . polysporum from Marion Lake sediments. (1 mm v e r t i c a l blackened area = 4 is o l a t e s ) T r i c h o d e r m a v i r i d e H y a l i n e M y c e l i a S t e r i l i a D a r k M y c e l i a S t e r i l i a T r i c h o d e r m a h a m a t u m T r i c h o d e r m a p o l y s p o r u m L J JIIN 1 9 7 0 AUG OCT DEC F E B 1971 FIGURE 7 Seasonal v a r i a t i o n - number of i s o l a t e s of Cephalosporium  acremonium, Trichoderma hamatum(NS), Trichoderma spp. and Umbelopsis versiformis from Marion Lake sediments. ( 2 . 5 mm v e r t i c a l blackened area = 1 i s o l a t e ) FIGURE 8 Seasonal variation - number of isolates of Cephalosporium  incarnatum var. macrosporum, Beauveria bassiana, Gliocladium roseum, Mammaria echinobotryoides, Aureobasidium  bolleyi, Chloridium chlamydosporis, Cephalosporium  incarnatum, Trichoderma saturnisporum, T\ koningii and Oedocephalum spp. from Marion Lake sediments. (2.5 mm vertical blackened area = 1 isolate) 101 C e p h a l o s p o r i u m i n c a r n a t u m v a r . m a c r o s p o r u m B e a u v e r i a b a s s i a n a G l i o c l a d i u m r e s e urn M a m m a r i a e c h i n o b o t r y o i d e s A u r e o b a s i d i u m b o l l e y i C h l o r i d i u m c h l a m y d o s p o r i s C e p h a l o s p o r i u m i n c a r n a t u m T r i c h o d e r m a s a t u r n i s p o r u m T r i c h o d e r m a k o n i n g i i FIGURE 9 Seasonal v a r i a t i o n - number of i s o l a t e s of Geotrichum  candidum, Cephalosporium spp. , Cylindrocarpon destructans, Paecilomyces elegans, Torulomyces lagena, A s p e r g i l l u s spp., P e s t a l o t i a monochaetioides, U n i d e n t i f i e d - 1 2 , V e r t i c i c l a d i e l l a procera and Gliocladium catenulatum from Marion Lake sediments. (2.5 mm v e r t i c a l blackened area = 1 i s o l a t e ) 103 © G e o t r i c h u m c a n d i d u m C e o h a l o s p o r i urn s p p . C y l i n d r o c a r p o n d e s t r u c t a n s P a e c i l o m y c e s e l e g a n s T o r u l o m y c e s l a g e n a A s p e r g i l l u s s p p . P e s t a l o t i a m o n o c h a e t i o i d e s U n i d e n t i f i e d — 12 V e r t i c i c l a d i e l l a p r o c e r a G l i o c l a d i u m c a t e n u l a t u m J U N 1 9 7 0 FIGURE 10 Seasonal variation - number of isolates of Phialophora fastigiata, Gliomastix murorum, Trichocladium opacum, Botrytis cinerea, Cladosporium herbarum, Thysanophora  penicillioides, Verticillium (?)terrestre, Phialophora spp., Gliomastix spp., Cephalosporium khandalense and Cladosporium cladosporioides from Marion Lake sediments. (2.5 mm vertical blackened area = 1 isolate) 105 ® P h i a l o p h o r a f a s t i g i a t a G l i o m a s t i x m u r o r u m T r i c h o c l a d i u m o p a c u m B o t r y t i s c i n e r e a C l a d o s p o r i u m h e r b a r u m T h y s a n o p h o r a p e n i c i l l i o i d e s V e r t i c i l l i u m ( ? ) t e r r e s t r e P h i a l o p h o r a s p p . G l i o m a s t i x s p p . C e p h a l o s p o r i u m k h - a n d a l e n s e C l a d o s p o r i u m c l a d o s p o r i o i d e s J J U N 1 9 7 0 AUG OCT DEC F E B 1 9 7 1 FIGURE 1 1 Seasonal variation - number of isolates of Geniculosporium  serpens, Gliocladium virens, Pestalotia versicolor, Coniothyrium sp., Sporobolomyces sp., Oidiodendron  periconioides, Paecilomyces spp., Aureobasidium pullulans, 0_. griseum, Cylindrocarpon didymum, Gliocladium spp. , Verticillium state of Nectria inventa, Cephalosporium  incoloratum, Pestalotia truncata and Phialophora sp. from Marion Lake sediments. (2.5 mm v e r t i c a l blackened area = 1 isolate) 107 © G e n i c u l o s p o r i u m s e r p e n s G l i o c l a d i u m v i r e n s P e s t a l o t i a v e r s i c o l o r C o n i o t h y r i u m s p . S p o r o b o l o m y c e s s p . . O i d i o d e n d r o n p e r i c o n i o i d e s P a e c i l o m y c e s s p p . A u r e o b a s i d i urn p u l l u l a n s O i d i o d e n d r o n g r i s e u m C y l i n d r o c a r p o n d i dymum G l i o c l a d i u m s p p . V e r t i c i l l i u m S t a t . N e c t r i a i n v e n t a C e p h a l o s p o r i u m i n c o l o r a t u m P e s t a l o t i a t r u n c a t a P h i a l o p h o r a s p . L J U N 1 9 7 0 AUG OCT DEC F E B 1 9 7 1 1/ FIGURE 12 Seasonal variation - percentage absolute season density of the seven most common Hyphomycetes from Marion Lake sediments. (1 mm vertical blackened area = approx. 1%) 109 © ( ? ) H u m i c o l a s p . P e n i c i l l i u r n s p p . T r i c h o d e r m a v i r i d e H y a l i n e M y c e l i a S t e r i l i a D a r k M y c e l i a S t e r i l i a T r i c h o d e r m a h a m a t u m T r i c h o d e r m a p o l y s p o r u m J U N 1 9 7 0 AUG OCT DEC F E B 1971 110 species and species groups may exhibit somewhat different seasonal changes as demonstrated in Figures 6-11. The detailed variation of each species or species group was discussed in the previous taxonomic section. Absolute season densities of the most common species, viz., (?)Humicola sp., Penicillium spp., Trichoderma viride, Hyaline and Dark Mycelia S t e r i l i a , T_. hamatum and T?. polysporum are illustrated in Figure 12. The changes in the absolute season densities generally followed the same trend as that of the actual number of isolations. It is worth noting that Penicillium spp. and _T. viride contributed almost equally to the population throughout the year, although their numbers of isolates varied during the study period. This may be attributed to the increase and decrease of other fungal taxa at the same time. The most dominant Hyphomycetes found were (?)Humicola sp., Penicillium spp., Trichoderma viride, Hyaline and Dark Mycelia S t e r i l i a . These constituted about 60% of the total fungal population of Marion Lake sediments. Spatial Occurrence and Distribution Presence or "absence, percentage frequency of spatial occurrence (percentage of stations showing positive recording) and numbers of isolates and species of Hyphomycetes from sediments of six Marion Lake stations are compiled in Tables V and VI. Appendix IV can be consulted for the detailed data of absolute station density (percentage of total isolates from each station) and the actual number of isolations. The distribution patterns of the eighteen most common Hyphomycetes based on the absolute station densi-ties are diagrammatically depicted in Figure 13. In the course of this study, a total of 73 species and species groups, excluding Penicillium species, belonging to 39 genera of SPATIAL DISTRIBUTION FUNGAL NAMES' 1 2 I" II I I] (?)Humicola sp. + + + + Penicillium spp. + + + + Trichoderma viride + + + + Hyaline Mycelia S t e r i l i a + + + + Dark Mycelia S t e r i l i a + + + + Trichoderma hamatum + + + + Trichoderma polysporum + + + Cephalosporium acremonium - + + + Trichoderma hamatum (NS) + + + -Trichoderma spp. + + + • -Trichoderma koningii + + + + Geotrichum candidum + + + + Paecilomyces elegens + + + + Cladosporium herbarum + - + -Cylindrocarpon destructans + + + -Beauveria bassiana + + + + Gliocladium roseum + + + -Mammaria echinobotryoides + - + -Cladosporium cladosporioides + - + -Gliocladium virens + - + -Phialophora spp. + - . - + Chloridium chlamydosporis + - + + Cephalosporium incarnatum - + + + var. macrosporum Pestalotia monochaetioides + - + -TABLE V F HYPHOMYCETES FROM MARION LAKE SEDIMENTS STATIONS 3 4 5 SECTIONS I II I II I II + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + - + + + + + - + + + + + + + -+ - + + + + + - + + + + + - + - + -+ + + + + -+ + + + - + + - + - + -+ + + - + + - + + - + + + - + - + + - + + + + + + - + - + -+ + + + - -+ _ + _ — _ % FREQUENCY OF 6 SPATIAL OCCURRENCE I II + + 100 + + • 100 + + 100 + + 100 + + 100 + + 100 + + 100 + + 100 + + 100 + + 100 + + 100 + + 100 + + 100 + - 100 + + 100 + - 100 + + 100 + - . 100 + - 100 + - 100 - + 100 - - 83 + + 83 + 83 FUNGAL NAMES Phialophora fastigiata Umbelopsis versiformis Pestalotia versicolor Oedocephalum spp. Thysanophora penicillioides Aureobasidium bolleyi Cephalosporium incarnatum Verticillium (?)terrestre Aspergillus spp. Trichoderma saturnisporum Cephalosporium spp. Oidiodendron periconioides Cephalosporium khandalense Unidentified—12 Gliocladium catanulatum Botrytis cinerea Pestalotia truncata Gliomastix murorum Aureobasidium pullulans Verticicladiella procera Torulomyces lagena Cylindrocarpon didymum Phialophora sp. (C163)** Verticillium state of Nectria inventa Cephalosporium incoloratum Geniculosporium serpens Coniothyrium sp. 1 2 I II I II + - + + + + + + + - + -- + + + + - - -- - + + - + + + + - - -+ - - -- - + -- - + + - - + -- - + -- - - + + - + -+ - + -+ - + -+ - + -+ _ _ _ + - - -- - + -- - + -_ _ - + - + + -+ - - -+ - -TABLE V —Continued STATIONS % FREQUENCY OF 3 4 5 6 SPATIAL OCCURRENCE SECTIONS I II I II I II I II + + + + - + - 83 + + - - + + - + 83 + - - - + - + - 83 - - + + + - + - 83 + - + - + + + - 83 + - + + - + + + 83 - - + - + - - - 66 + - - - + - + - 66 - + - - + - + - 66 + + - - - + + - 66 + - - + - - + - 66 + - + - - - + + 66 + - + - - - + - 66 + - - + + - - - 66 + + - - - - - - 50 + - - - - - - - 50 - - + - - - - - 50 - - + - - - - - 50 + + - - + - - - 50 - - + - + - - - 50 + + + + - - - - 50 + - + - - - - - 50 + - - - - - + - 50 + - + - + - - - 50 _ _ _ _ _ _ _ _ 3 3 + - - - - - - - 33 _ _ _ _ _ + 3 3 TABLE V —Continued FUNGAL NAMES STATIONS 1 2 3 4 5 6 % FREQUENCY OF SECTIONS SPATIAL OCCURRENCE I II I II I II I II I II I II Cylindrocarpon (?)lucidum + - - - - - - + 33 Candida sp. + - - - - - - - - + 33 Gliocladium spp. - - + + + + - - - - 33 Trichocladium opacum - - + - + - - - - - - - 33 Periconiella sp. - + - - - + - - 33 Paecilomyces spp. - - + - - - - - - - + 33 Oidiodendron griseum - - - + - - - - - + 33 Gliomastix spp. - - - - - - + - + - 33 Cladosporium macrocarpum + - - - _ _ _ _ _ _ - 16 Chrysosporium pannorum + - - - - - - - - - - 16 Paecilomyces terricola - - + - - - - ' - - - - 16 Sporothrix sp. - - + - - - - - 16 Cordana pauciseptata - - - + - - - - - - - 16 Cladosporium musae - - - + - - - - - - - 16 Septonema secedens - - - - + - - - 16 Metarrhizium anisopliae - - - + - - - - - 16 (?)Acrogenospora state of - - - - - - - - + - - - 16 Farlowiella carmichaeliana Paecilomyces roseolus - - - - - + - - 16 Paecilomyces carneus - - - - - - - + - - - 16 Alternaria alternata - - - - - - + - - 16 Sporobolomyces sp. - - - - - - - + - 16 Arthrinium sacchari - - - - - - - - + - 16 + = present; - = absent ** Author's stock culture number TABLE VI A SUMMARY OF THE NUMBERS OF ISOLATES, SPECIES AND SPECIES GROUPS OF HYPHOMYCETES RECORDED FROM MARION LAKE SEDIMENTS STATIONS 1 2 3 4 5 6 SECTIONS I II I II I II I II I II I II Number of collections 5 5 5 4 4 5 Number of isolates 247 98 364 138 510 133 201 68 225 111 216 90 Total number of isolates 345 502 643 269 336 306 Average number of isolates per collection 69.0 100.4 128.6 67.3 56.3 61.2 Number of species and species groups 40 21 45 24 47 27 37 22 36 23 37 24 Total number of species and species groups 45 48 52 40 41 43 Average number of species and species groups per collection 9.0 9.6 10.4 10.0 10.3 8. 6 FIGURE 13 Percentage absolute station density of more common Hyphomycetes from Marion Lake sediments. ( ? ) H u m i c o l a s p . P e n i c i l l i u m s p p . T r i c h o d e r m a s p p . T r i c h o d e r m a v i r i d e H y a l i n e M y c e l i a S t e r i l i a C e p h a l o s p o r i u m acremonium T r i choderma hamatum T r i c h o d e r m a p o l y s p o r u m C e p h a l o s p o r i u m acremonium T r i choderma hamatum (NS) T r i c h o d e r m a k o n i n g i i G e o t r i c h u m c a n d l d u m P a e c i l o m y c e s e l e g a n s C l a d o s p o r i u m h e r b a r u m C y l i n d r o c a r p o n d e s t r u e t a n s B e a u v e r i a bass1 ana U m b e l o p s i s v e r s i f o r m i s C e p h a l o s p o r i u m I n c a r n a t u m v a r . macrosporum STATIONS 1 FIGURE 13 117 of Hyphomycetes were identified. Among these, 24 genera were represented by a single species. Table VI revealed that the largest number of isolates per collection was found at Station 3 and the lowest at Station 5. When considering the species isolated, Table VI also shows that Stations 3, 4 and 5 were not different significantly in the average number of species recorded. Nevertheless, Station 3 had a greater number of colonies (about twice as many or more) than Station 4 or Station 5. The high numbers of isolates in the former were due to colonies of a few species, especially (?)Humicola sp., Trichoderma viride and Penicillium spp., Station 6 had the lowest number of species isolated per collection. Twenty species and species groups, viz., (?)Humicola sp., Penicillium spp., _ viride, Hyaline and Dark Mycelia S t e r i l i a , T_. hamatum, T_. hamatum(NS), T_. polysporum, T. koningii, Cephalosporium acremonium, Geotriehum candidum, Paecilomyces elegans, Cladosporium herbarum, Cylindrocarpon destructans, Beauveria bassiana, Gliocladium roseum, Mammaria echinobotryoides, Cladosporium cladosporioides, Gliocladium virens and Phialophora spp. occurred throughout the lake. Some of these widely distributed Hyphomy-cetes were recorded very abundantly whenever found. The most dominant ones were (?)Humicola sp., Penicillium spp., J:. viride, Hyaline and Dark Mycelia S t e r i l i a . They formed a high proportion, 48% to 64%, of the total isola-tions at each station. However, some of the widely scattered Hyphomycetes were represented only by a few isolates, for example, M. echinobotryoides, CI. cladosporioides, C_ herbarum, Ji. bassiana and G_. roseum. In general, i t appeared that the species or species groups with a frequency of spatial occurrence less than 50%, i.e., those that occurred only once or twice, were represented, usually, by a low number of isolations. It was indicated in Table VI that not only a greater number of 118 i s o l a t i o n s but also more species were recorded from the surface (Section I) sediments than from the lower (Section II) sediments at a l l s i x s t a t i o n s . Although A l t e r n a r i a a l t e r n a t a , Metarrhizium a n i s o p l i a e and Septonema secedens were c o l l e c t e d only from the lower sediments i n t h i s study, t h i s f i n d i n g may be merely f o r t u i t o u s since each of them was represented by only a s i n g l e i s o l a t e . Generally, 75% or more of the Hyphomycetes i s o l a t e d from the lower sediments could be expected also from the surface sediments. Table VII provides the combined data concerning seasonal v a r i a t i o n and s p a t i a l d i s t r i b u t i o n of Hyphomycetes from Marion Lake sediments. The o v e r - a l l r e s u l t was that those species or species groups which were the most extensively d i s t r i b u t e d also were most constantly recovered. In p a r t i c u l a r , (?)Humicola sp., P e n i c i l l i u m spp., Trichoderma v i r i d e , _T. hamatum, T_. polysporum, Cephalosporium acremonium, Beauveria bassiana, Gliocladium roseum, Mammaria echinobotryoides, Hyaline and Dark Mycelia S t e r i l i a were found throughout the lake and i n a l l seasons of the year. The d i s t r i b u t i o n patterns of each of the Hyphomycetes i s o l a t e d during the study were discussed with t h e i r seasonal v a r i a t i o n i n the previous taxonomic section. Since the present work emphasized the study of Hyphomycetes, no s p e c i a l i s o l a t i o n technique or. i s o l a t i o n medium was employed for the recovery of Phycomycetes and Ascomycetes. However, Phycomycetes were represented i n the c o l l e c t i o n s by Mucor and M o r t i e r e l l a . M o r t i e r e l l a  i s a b e l l i n a Oud., and M. vinacea Dixon-Stewart were i d e n t i f i e d . Mucor spp. and M. vinacea were found extensively throughout the lake, p a r t i c u l a r l y i n the surface muds. No s i g n i f i c a n t seasonal v a r i a t i o n of M. vinacea was observed. On the other hand, Mucor spp. were c o l l e c t e d more .abundantly i n TABLE VII FUNGAL NAMES SPATIAL AND SEASONAL DISTRIBUTION OF HYPHOMYCETES ISOLATED FROM MARION LAKE SEDIMENTS (J=Jun. 1970; A=Aug. 1970; OOct. 1970; D=Dec. 1970; F=Feb. 1971) (WINTER SEASON SHADED) J A 1 0 D 2 J A 0 D F STATIONS 3 J A 0 D F 4 A 0 D F J A 0 D F J A 0 D F (?)Acrogenospora state of Farlowiella carmichaeliana Alternaria alternata Arthrinium sacchari Aspergillus spp. Aureobasidium bolleyi A. pullulans Beauveria bassiana Botrytis cinera Candida sp. Cephalosporium acremonium C. incarnatum C. incarnatum var. macrosporum C. incoloratum C. khandalense Cephalosporium spp. Chloridium chlamydosporis Chrysosporium pannorum Cladosporium cladosporioides C. herbarum C. macrocarpum C. musae Coniothyrium sp. Cordana pauciseptata - + -+ + + -- + + + - + -+ + :+ + - + + + + + + + + + + + + + + - + -+ + + + + + + - + + + - + + - + -+ - + -+ + + + + + + + -- + -+ - + + + - -+ + + + - + - + -+ + + - + -- + -+ TABLE VII —Continued FUNGAL NAMES STATIONS Cylindrocarpon destructans C. didymum C. (?)lucidum Geniculosporium serpens Geotrichum candidum Gliocladium catenulatum G. roseum G. virens Gliocladium spp. Gliomastix murorum Gliomastix spp. (?)Humicola sp. Mammaria echinobotryoides Metarrhizium anisopliae Oedocephalum spp. Oidiodendron griseum 0. periconioides Paecilomyces carneus P. elegans P. roseolus P. t e r r i c o l a Paecilomyces spp. P e n i c i l l i u m spp. P e r i c o n i e l l a sp. P e s t a l o t i a monochaetioides P. truncata P. v e r s i c o l o r J A 0 D F ":f. + + + + + + + + + + + + + + + J A 0 D F - + -•-: + + + + + + - + -+ + + - + + + + + + + + + + + + :+ + + + - + -+ + - + -+ + + + + + - + + - + -r + + + + + + - - + + - + + - + -- + -+ - + -- + + D F •+: + : +• - f j +: +: +; +: +: +: :+: J A O D F : J A O D F h + - + + + — + + + + + -- + - - + - + -+ + + + - + + + - + + — + + + — + — + — + — + + - + -+ + + + - + + — TABLE VII —Continued FUNGAL NAMES STATIONS 1 2 3 4 5 6 J A 0 D F J A 0 D F J A 0 D F J A 0 D F J A 0 D F J A 0 D Phialophora fastigiata - - 4 .4 - 4 : H + - '- - - -; t : H - - : ~ : r i - - 4: Phialophora sp.(C163) - - - - x - 4ii-•: - 4 j-j - - - : *: *• t: - - -:-?:" - - 4i Phialophora spp. - - + 4i - + 4 i r - 4 4i - - - '• — — + i _ : 4 — 4-Septonema secedens - - - 4 - - — - — — 4> — — — — .-r . .—. — Sporobolomyces sp. - - - -7 :-: - - 4 : : - -. : — - — — — — "r: :_ t; — — "~ ' ~ ~ 4- T . Sporothrix sp. - - - - - - - — ^ • - — + — — — — T: r _ — !T'. r*! — ~-Thysanophora penicillioides - - - •j-j - - - -; - — — — 4> — — — • • — — + : 4 : ^ — 4: Torulomyces lagena - - - 4 :-: + - - :- '• - 4- - 4 4 — 4- — -K :-7'. — — — :4::-: — "T . Trichocladium opacum - - - 4 - - •: - 4- 4- — — — — T: r T : — — — :T : rt — — [ Trichoderma hamatum + + + 4 4 + - + 4i '1 • i i + 4- 4- 4 - 4- 4- 4-: :-f-: 4- 4- 4- :4:4| 4- 4- 4- +: T. hamatum(NS) - + 4 4 - - + r : 4- 4- 4- 4 4 - - 4- +::-r: - 4- 4- i4 i4 — 4 4- 4: T. koningii - - 4 4 + - +:r' l i : 4- 4- 4 + - 4- 4- +: : :: - - - + — — 4- 4: +: T. polysporum - 4- 4- 4 + + + 4 i : 4- 4- + - 4- 4- 4-: :- 4- + : 4 : ^ — 4- 4-T. saturnisporum - - - 4 :-: - - + 4 : :- : + - 4 — - — 4 : :• "T : — 4- - : 4 : H — — T. viride + 4- 4- 4 4 + 4- + 4:'r it: + + 4- + + - - 4- +:: f : + 4- + i - r i + 4- 4- 4i Trichoderma spp. + - + 4 * - + 4: : • i i + 4- + - - 4- 4 : :-£•: - - 4- :4:4r - 4- 4- 4: Umbelopsis versiformis 4- - - 4 4 :• + + + +: :-B: + + - 4 :-:. — - - •f: :• T : 4- 4- 4- i4::-: — V e r t i c i c l a d i e l l a procera - - - 4 4 - - -.: - — — -7 — — 4- 4- —; ; - ; — — + i - r i r i — — * Verticillium state of Nectria inventa - - - 4 :-: - - - f i * ;: - - - 4 :4 — — 4- 4 : : 4 : - — 4- i4:n — — -T. V. (?)terrestre - - + 4 i-i - - - 4 : :--.: - 4- •7 — - - *: * ; — — — :*t: — — — 4' Hyaline Mycelia S t e r i l i a + + 4- 4 4 + 4- + •+:: t i i + - 4- 4 r f - 4- + +i! f : + 4- 4- 4- 4- 4- 4 Dark Mycelia S t e r i l i a + + 4- -i- f. : + + r f i : f i + 4- 4- 4 :+ - 4- 4- .4-::-4: 4- 4- 4- : 4 : 4 ; — 4- 4- + Unidentified—12 - - - 4 •T. - - + : 4 : :• -:: 4- - -r :-: — 4- - 4: — - i-?i4 — ~ — T Author's stock culture number the winter and were t o t a l l y absent i n the August samples. Only two i s o l a t e s of M. i s a b e l l i n a were recorded from Station 6 in winter samples (December and February). Three species of Ascomycetes were i s o l a t e d and i d e n t i f i e d . They were Anixiopsis sp., Emericellopsis t e r r i c o l a van Beyma and Pseudoeurotium zonatum. A few of the species l i s t e d i n Table V are known to be the c o n i d i a l state of Ascomycetes. Their c o n i d i a l state names are used i n the present study since these names are better, known in the l i t e r a t u r e and sexual stages were not observed. Anixiopsis sp. and P_. zonatum were more abundantly recorded from the lake than E. t e r r i c o l a . During the course of the work, two i s o l a t e s showed well developed clamp connections when cultured on PDA. I t was not possible to i d e n t i f y these two (?)Basidiomycetes and they were l o s t i n further t r a n s f e r s . DISCUSSION 123 The present study on the occurrence, distribution and seasonal variation provides a basic core of information on the hyphomycetous population of Marion Lake sediments. A modified dilution plate method was used in this work with the hope of overcoming some of the criticisms that can be made of the dilution plate method. The addition of rose-bengal to the isolating media was found especially valuable in suppressing growth of fast-growing fungal colonies and in limiting the growth of other microorganisms. Likewise, transfer of colonies as soon as they were detectable enabled a more com-plete isolation of the fungi. However, i t can not be denied that the results (Tables IV and V) do not give the total picture of Marion Lake Hyphomycetes. This underestimation can be attributed to the usual d i f f i -culties encountered in studies of s o i l fungi. First of a l l , the problems of accurate identification of the fungi isolated were ever present. Species of the genus Penicillium were not identified, and those of Cephalosporium, Gliocladium, Phialophora and Trichoderma were named only i f they could be identified with certainty using available keys and references. Finding and studying the perfect stage may help in identifying satisfactorily some of these fungi which have such a great similarity in their conidial stages (Bhatt, 1965). Another problem was that some isolates, most of them slow growing, were lost on the f i r s t transfer to PDA. Furthermore, a number of isolates remained st e r i l e and consequently were grouped as Hyaline or Dark Mycelia S t e r i l i a according to their colour appearance on PDA. Finally, lack of sufficient characteristics of some isolates made i t impossible to assign them to a species or, in some cases, even to a higher taxonomic rank. Therefore, they were listed as "sp." 124 or "unidentified!'. Unfortunately, the modified dilution plate method provided no solution to the most c r i t i c a l d i f f i c u l t y , that of differentiating the active fungi from dormant fungi. However, none of the existing methods are very successful in isolating active fungi from s o i l (Chou and Stephen, 1968). If i t is assumed that sporulation of microfungi occurs after vegetative growth, enumeration of propagules i s , to some extent, an indica-tion of biological activity (Montegut, 1960; Witkamp, 1960). Montegut further noted that "... For the world-wide analysis of microflora in different horizons of a given s o i l , for the determination of the frequency and i t s variations to ecological factors, for a l l comparative study, only the dilution method (and in some cases the direct-inoculation method) can give coherent results". With respect to the two isolating media (Czapek solution agar and 2% Malt agar) employed for the isolation of fungi in this study, the results show that the most dominant and abundant fungi can be recovered by either one of the two. Yet, these two media are complementary to each other in isolating the less common fungi and their joint use resulted in a more complete enumeration of the actual fungal population<of the lake muds. However, the author certainly is well aware of the inadequacies of these two rich media, both of which favour the development of fast-growing fungi and are not so suitable for the sporulation of many ste r i l e forms. Hence, not only different methods but also a variety of media should be employed, i f possible, in any study with the object of gaining maximum understanding of the s o i l fungi (Chesters, 1948; Warcup, 1951, 1957; Brown, 1958; Bhatt, 1965). Although isolation of the common fungi did not seem to be affected by the incubation temperature, a greater variety of fungi and colonies of the dominant fungi were recorded when incubating at 25 C than 5°C. This is in accordance with the finding of Sugiyama et a l . (1967) that the numbers of fungal strains isolated under 25°C incubation was higher (four times) than those incubated under 10°C in Lake Vanda, Antarctica. There i s , of course, the possibility that longer periods of incubation at 5°C would bring out those less common fungi which may be considered as a significant component of the population as long as they exhibit activity. It was noticed that some species, particularly (?)Humicola sp., and Trichoderma polysporum showed no significant d i f f e r -ence in the number of isolates at the two incubation temperatures. Nevertheless, incubation at 25°C obviously accelerated the recovery of fungi. Since the information on the geofungi in fresh-water sediments i s so meagre, the results of the present study w i l l be compared also with the enormous knowledge of s o i l fungi in ter r e s t r i a l habitat. It i s generally known that among the major factors governing the occurrence and distribution of s o i l fungi are temperature, pH, moisture, percentage of organic matter, vegetation, s o i l treatment and many others (Warcup, 1951; Waid, 1960; Taha et a l . , 1967; Park, 1968; Gr i f f i n , 1972). Warcup (1951) and Parkinson and Balasooriya (1967) reported the importance of pH in influencing the mycoflora in the s o i l . Jensen (1931) and Warcup (1951) noted that certain fungal species were common in alkaline soils and others in acid soils. It is accepted generally that acid soils provided a more favourable environment for fungi (Jensen, 1934; Tresner et a l . , 1954; Pugh, 1962). To the contrary, Dayal and Gupta (1967) isolated the maximum number of fungal species from alkaline soils (pH 8.0 - 8.4) in their studies in India. Mehrotra and Kakkar (1972) found that fungi were 126 abundant in alkaline soils and played a dominant role in microbiological activity. The l i t t l e change in the pH value of Marion Lake sediments through the year indicates that pH may not be a significant factor in affecting the fungal occurrence, distribution or seasonal variation in this lake. However, the slight increase in acidity in October may account partly for the increase in the number of fungi isolated in this season. The relations of temperature and moisture to the microbial popula-tions of s o i l have been observed by many investigators (Cobb, 1932; Timonin, 1935; Tresner et a l . , 1954; Saksena, 1955; Warcup, 1957; Cooke, 1958; Borut, 1960; Williams and Parkinson, 1964; Dayal and Gupta, 1967; Taha et a l . , 1967; Parkinson and Balasooriya, 1969; Mehrotra and Kakkar, 1972) and their various findings are often contradictory. Of course, moisture is irrelevant in the present investigation of lake muds. The data obtained in this study show no apparent correlation between the tem-perature and the numbers of fungi isolated from Marion Lake muds. The higher number of fungi in the winter months and at the deeper-water station (Station 3) where the temperature was lowest for the stations studied, suggests an indirect effect of temperature on fungal activity. The definite correlation of microorganisms with organic matter content of the s o i l has been reported by Gray and McMaster, 1933; Jensen, 1934; Gray and Taylor, 1935; Timonin, 1935; Taylor, 1948; Martin and Aldrich, 1954; McLennan and Ducker, 1954; Tresner et a l . , 1954; Borut, 1960; Kendrick, 1962; Dayal and Gupta, 1967; Gochenaur and Whittingham, 1967; Is h i i , 1969; Varghese, 1972. The organic matter content of Marion Lake sediments recorded during the study ranged from 24.1% to 31.2%. Wali ejt a l . (1972) obtained a higher percentage, 40% to 45%, based on a "loss on ignition" assay method. Despite the higher viable fungal count 127 which corresponds to the comparably high organic matter content in early winter and at Station 3, i t is d i f f i c u l t to correlate the one cycle fluctuation of fungal numbers with the irregular pattern of organic matter in the lake. It seems quite l i k e l y that organic matter content is not a major factor controlling the distribution and occurrence of fungi in Marion Lake sediments. These results lead me to agree with Saksena's (1955) viewpoint, also quoted by Dayal and Gupta (1967), that " . . . i t i s not feasible to lay emphasis on any particular observation on fungi and to correlate i t to a single factor unless the latter becomes the limiting factor". Regarding the seasonal fluctuations of s o i l mycoflora, the results of individual observations are again variable. Some workers did not detect any seasonal variation (Jensen, 1934; Martin and Aldrich, 1954; Borut, 1960; Brandsberg, 1969), while others (Warcup, 1951; Thrower, 1954; Williams and Parkinson, 1964; Gams and Domsch, 1969; Parkinson and Balassoriya, 1969) emphasized the spatial variation in the s o i l mycoflora and concluded that the observed seasonal variation was merely the reflec-tion of the heterogenous spatial distribution of fungi rather than an actual seasonal fluctuation. However, other workers have demonstrated a seasonal variation in s o i l mycoflora, but the pattern of fluctuation i s diverse. A winter maximum was observed in a Southern Wisconsin forest s o i l by Tresner jet a l . (1954); in a South Australia wheat-field s o i l by Warcup (1957); in Netherlands forest soils by Witkamp (1960); in Ontario forest soils by Bhatt (1965); and in agricultural f i e l d s o i l in India by Mehrotra and Kakkar (1972). Cobb (1932) noted that there were larger numbers of fungi collected in spring and late winter than in summer and f a l l in forest soils of New York, while Timonin (1935) and Cooke (1968) 128 In studies of s o i l fungi in Manitoba and Colorado respectively, reported a higher fungal count in f a l l than in spring or summer. Thornton (1956) found that most mycelium was present in an English oakwood and heath s o i l during summer and least in winter. Greater numbers of fungi were detected in summer sampling than in winter by Miller e_t a l . (1957) in forest and cultivated soils in Georgia. Differences in seasonal patterns are not unexpected when one considers that a l l these reports involved different geographical locations, different s o i l characteristics and different environmental conditions. Furthermore, differences in isolation techniques and media employed also may account for some of the variations. The results of my study (Figure 4) show that a maximum number of viable fungi occurred during the winter. Since no single factor studied could explain the seasonal pattern of fungi from Marion Lake sediments, i t is speculated that the fluctuation of total viable count observed in my study results from the combined action of many factors in different degrees and at different times. For example, the highest numerical counts recorded in early winter could be due to an increase in available organic matter in the preceding f a l l (Figure 2). The supply of organic material may come from the leaf f a l l in the autumn; from the surface runoff and seepage of the surrounding vegetation, as pointed out by Wali et a l . (1972); from the phytoplankton or aquatic plants inhabiting the lake; or from the inlet stream in particulate or soluble forms. The readily decomposable organic material stimulates microbial activity. However, the low temperatures in the f a l l may not be favourable for bacteria or actinomycetes, and con-sequently results in a less competitive condition for fungal activity (Witkamp, 1960). Active mycelial growth would be expressed then in the subsequent collections (in this case in December) in terms of an increase 129 in the number of colonies. In addition, the characteristic heavy r a i n f a l l in late f a l l and early winter (Efford, 1967) may bring into the lake con-siderable numbers of fungal spores from the atmosphere and the surrounding terrain which would contribute to the winter increase in the total viable counts. The results from Marion Lake (Table IV and Appendix III) also indicate that the increase in total isolations from summer to winter was due largely to the increase in numbers of colonies of the dominant species as well as a variety of species absent in summer, e.g., Cladosporium  herbarum, Thysanophora penicillioides, Cephalosporium khandalense and Gliocladium catenulatum. It is interesting to note that fj. herbarum and T_. penicillioides are considered usually to be associated with either functional or decaying leaves. Presumably these species were carried into the lake together with the fallen leaves. Accordingly, even though the greatest variety of species is isolated during the winter, washed-in or carried-in species may eventually find the condition unsuitable for further growth and gradually be eliminated as the seasons progress. The gradual decrease in the count after early winter coincides with both the exhaustion of organic matter and the low temperature. In spring, the increase in temperature and the release of nutrients following thawing possibly induce bacterial growth which is reflected in a decrease in the total fungal counts due to competition. This was confirmed by Fraker (1971) in her one-year study (July, 1969 to June, 1970) of bacteria from Marion Lake muds in which she obtained the highest bacterial counts from April to July, 1970. The increase in fungal counts in summer may indicate that by this time some fungi are gradually beginning to degrade the more resistant substrates in the sediments. 130 As far as spatial distribution was concerned, the highest count as well as the largest number of species was found at Station 3, the deep-water station. There is a tendency for both numbers of isolations and numbers of species to diminish from the center lake muds to the margin muds, that i s , from Station 3 to Station 2 to Station 1 (Table VI). This trend compares favourably to the corresponding decrease in organic matter content in that order. Besides, the nature of the topographic condition and the water currents of the lake (Potter and Baker, 1961) may be import-ant factors too. At present, the actual importance of currents can not be determined with certainty since no information on the water flow is avail-able. It is probable that a gradual sedimentation results in a greater fungal population towards the lake center. This would be in accordance with the findings of Potter and Baker (1956) for Flathead Lake, Montana. They reported that the greatest variety of species occurred at the deep station muds. In Marion Lake, relatively high numbers of species were isolated from the inlet station (Station 5) although the viable count was low. The lowest number of species was found at the outlet station (Station 6). This was anticipated since the organic matter content was the lowest at Station 6. It is well-established that the numbers of colonies, as well as the total numbers of species, tend to decrease with increase in s o i l depth (Cobb, 1932; Warcup, 1951; Saksena, 1955; Borut, 1960; Wolf and Cavaliere, 1966'; Wolf, 1967; Chou and Stephen, 1968; Mehrotra and Kakkar, 1972). Results from Marion Lake in which the fungi isolated from surface and lower sediments were compared (Table VI) substantiate this view. Since greater number and variety of fungi are believed to be an indication of fungal activity, i t follows that the surface of the lake mud is the site of 131 the most intensive microbial activity (Taylor, 1948; Harrison et. a l . , 1971). However, Waksman (1916), Tresner et a l . (1954) and Miller et a l . (1957) found that only the numbers of fungi but not the species diversity de-creased with depth and Sewell (1959a) noted that a few species, such as Mucor ramannianus Moll., Periconia (syn. Trichobotrys) sp., and st e r i l e mycelial forms showed a reverse distribution, that i s , they were relatively abundant in the subsurface horizons of the Calluna-Heathland s o i l he studied. In general, these species which were recorded from lower sediments of Marion Lake were isolated also from surface sediments although usually with a higher density. Exceptions to this were noticed: (?)Humicola sp., and Beauveria bassiana whose distribution showed no influence by depth; and Phialophora spp. which were more abundant in the deeper s o i l as noted in the studies of Bhatt (1965) and Parkinson and Balasooriya (1967). The most striking feature of this investigation is the qualitative results obtained. Hyphomycetes isolated in this investigation are those which regularly appear in reports of s o i l fungi from garden, cultivated and forest soils. These results suggest that there is no distinct hyphomycetous population in the lake muds. In their study of Montana lakes, Potter and Baker (1956, 1961) concluded that the size of the lake is more significant in the occurrence of fungus species than the limnological type of the lake, i.e. eutrophic or oligotrophic. Data from Marion Lake do not seem to support their viewpoint, for the number of species of Hyphomycetes recorded from Marion Lake muds is far greater than that reported from Montana lakes or Vanda Lake, Antarctica (Sugiyama at a l . , 1967) despite the smaller size of Marion Lake. Information on the fungal populations of lake sediments is so meagre generally that further research on a number of lakes is necessary 132 i f any significant comparisons are to be made. As in other l i s t s of s o i l fungi (Waksman, 1916; Jensen, 1931; Cobb, 1932; Bisby et a l . , 1935; Warcup, 1951; McLennan and Ducker, 1954; Miller et a l . , 1957; Sewell, 1959a, 1959b; Gochenaur and Whittingham, 1967; Gochenaur and Backus, 1967; Chou and Stephen, 1968; Kamal and Bhargava, 1970), Penicillium and Trichoderma are two of the most dominant genera in Marion Lake muds. Aspergillus is represented only by four isolates, of which three were recorded in summer. The abundance of Penicillium and rarity of Aspergillus supports the general view that P e n i c i l l i a are more common in North Temperate soils and Aspergilli in southern warm soils (Werkenthin, 1916; Waksman, 1917; Jensen, 1931; Bisby et a l . , 1935; Chesters, 1949; Warcup, 1955; Garrett, 1956; Pugh, 1966; Dayal and Gupta, 1967; Morrall and Vanterpool, 1968; Kamal and Bhargava, 1970; Domsch and Gams, 1972). Tresner et a l . (1954) reported that Aspergillus was poorly represented in forest soils. Miller et a l . (1957) also demonstrated the dominance of Penicillium species in forest soils and Aspergillus species in cultivated s o i l s . The occurrence of P e n i c i l l i a in Marion Lake was rather constant in a l l seasons and throughout the lake, although they were more abundant in winter and constituted a larger proportion of isolates at the lake-margin stations. Likewise, Trichoderma, particularly T_. viride, can be found at every station in every season. Cobb (1932) noticed that the numbers of Trichoderma became lower when Penicillium increased and vice versa, there-by implying some mutual seasonal relationship between Penicillium and Trichoderma. The seasonal fluctuations of T. viride and Penicillium in Marion Lake (Figure 6) suggest such a relationship, but only slightly. Trichoderma usually is considered as one of the most active decomposers of 133 cellulose and other complex organic substances (Waksman, 1932; Bisby et a l . , 1935; Domsch and Gams, 1972). My data (Appendix III) reveal that the increase in isolations of Penicillium and Trichoderma species in f a l l and winter accounted for 40% of the total increase of isolations in those seasons. Thus, to some extent, these organisms must play an important role in the decomposition of organic matter in the lake during these seasons of leaf f a l l and increased precipitation. It is noteworthy that no Fusarium was recorded from Marion Lake muds although Potter and Baker (1961) reported Fusarium sp. to be ubiqui-tous in both water and mud samples of Montana lakes. Several investiga-tions (Waksman, 1916; Bisby. et a l . , 1935; Warcup, 1951; Miller et a l . , 1957; Park, 1963; Chou and Stephen, 1968; Morrall and Vanterpool, 1968) found Fusarium spp. abundant in grassland and cultivated soils but rare in forest soils. It has been observed also that Fusarium particularly favours neutral to alkaline soils (Jensen, 1931; Bisby et a l . , 1935; Warcup, 1951; Tresner et a l . , 1954; Thornton, 1956; Sewell, 1959a; Christensen et a l . , 1962; Pugh, 1964; Bhatt, 1965, 1970), which may help partially explain the absence of the genus in Marion Lake. As in most studies of s o i l fungi, no Basidiomycetes were identi-fied during the investigation. The lack of satisfactory technique and failure to stimulate fructifications in culture are the main obstacles encountered (Miller et a l . , 1957; Warcup, 1959). Bhatt (1970) suggested the possibility that "... the fungi so frequently recorded as s t e r i l e dark mycelium represented monokaryotic Basidiomycetes". The most distinctly different organism isolated from Marion Lake is (?)Humicola sp.. It forms an integral part of the hyphomycetous popu-lation of Marion Lake muds. The slow-growing nature of the fungus makes 134 i t a weak competitor when other fast-growing fungi are prevalent; but the formation of chlamydospores and dark conidia enhances i t s a b i l i t y to sur-vive unfavourable conditions. This is a possible explanation of why (?)Humicola sp. decreased during f a l l and winter, yet formed a large pro-portion of summer samples. It is postulated that (?)Humicola sp., in contrast to Trichoderma, Penicillium and Mycelia S t e r i l i a , is more active in the u t i l i z a t i o n of complex substrates. From the data obtained (Tables IV and V; Appendices III and IV), i t is obvious that Mycelia S t e r i l i a , both dark and hyaline forms, are very abundant in Marion Lake sediments. This is in contrast to the typical l i s t of s o i l fungi arising from studies u t i l i z i n g the dilution plate method. It suggests that the modified dilution plate method is valuable in the iso-lation of this active component of the fungous population. The identity of Mycelia S t e r i l i a i s uncertain. Barron (1968) has pointed out that this group is a "catchall" which often includes a large number of nondescript mycelial isolates which f a i l to sporulate under normal laboratory condition or, as stated earlier, may represent monokaryotic stages of Basidiomycetes. The present investigation of sediment fungi in Marion Lake has shown the sizable and diverse population of Hyphomycetes in the sediments of a lake, and i t s similarity in composition to the Hyphomycetes of soils. This finding leads me to agree with Taylor (1948), that "... the surface of the lake mud is by far the most active site for microbiological activity and where the common biological processes which normally occur in soils also take place when sufficient oxygen is present." Though this.general study of Hyphomycetes in* Marion Lake muds has not provided any definitive answers to the roles of these fungi in nature, 135 i t i s only when such basic information i s a v a i l a b l e that further research into t h e i r a c t i v i t i e s and r o l e s i n the lake ecosystem can be s u c c e s s f u l l y conducted. 136 PART II CELLULOLYTIC ABILITY OF FUNGI ISOLATED FROM MARION LAKE SEDIMENTS AS DETERMINED BY THE AGAR-DIFFUSION METHOD INTRODUCTION Large quantities of organic matter come from higher plants, of which cellulose is the most important fraction and subsequent microbial decomposition of this cellulose plays a very significant role in the carbon cycle. The a b i l i t y of fungi and bacteria to attack cellulose is well-established (van Iterson, 1904; Scales, 1915; McBeth, 1916; Waksman, 1916, 1940; Waksman and Starkey, 1924; Dubos, 1928; Alexander, 1961; Henis et a l . , 1961; Witkamp, 1963; Pugh, 1964; Norkrans, 1967). Fungi Imperfecti and Ascomycetes are perhaps of greater importance in cellulose decomposition than any other fungal groups (Waksman and Skinner, 1926; Waksman, 1940; Norkrans, 1967). Methods for measuring the ce l l u l o l y t i c a b i l i t y of microorganisms are numerous, e.g. (a) weight loss of cellulose substances, e.g. cotton sliver (Rautela and Cowling, 1966); (b) loss in tensile strength of cotton duck (Reese and Dowing, 1951; Rautela and Cowling, 1966); (c) production of reducing sugars from CMC (carboxymethyl cellulose) (Reese and Levinson, 1952; Reese and Mandels, 1963; Domsch and Gams, 1969; Fergus, 1969); (d) clearing of cellulose media (Walseth, 1952; Eggins and Pugh, 1962; Rautela and Cowling, 1966). Rautela and Cowling (1966) described a simple "Agar-Diffusion Method" which is based on the principle that extra-cellular dissolution of cellulose i s an essential aspect of i t s degradation and c e l l u l o l y t i c activities of the testing fungi are determined by measur-ing depth of clearing of opaque acid-swollen cellulose column. They com-pared i t with the previously mentioned conventional methods for determining 137 the relative c e l l u l o l y t i c activity of fungi and concluded that their, test is not only simple but also reliable. Their results were well correlated with the degradation of native cellulose which has been considered as the most accurate method for the determination of cellulose decomposition. Recently, using Rautela and Cowling's technique, Tansey (1971) studied the c e l l u l o l y t i c a b i l i t y of thermophilic fungi isolated from self-heating wood chips. In the study of sediment fungi in Marion Lake (Part I), a sizable and diverse population of Hyphomycetes was isolated. The Agar-Diffusion method of Tansey (1971) was used to compare the relative c e l l u l o l y t i c a b i l i t y of these fungi. 138 MATERIALS AND METHODS Preparation of acid-swollen cellulose and the assay medium as described by Tansey (1971) were followed with a few slight modifications. It is outlined below: PREPARATION OF ACID-SWOLLEN CELLULOSE IN COLD ROOM AT 4°C 1. Thirty grams of Whatman Cellulose powder CF 11 (for Column Chromatography, W. & R. Balston Ltd., England) were placed into each of two beakers. 2. To each of these, 400 ml of 85% ortho-phosphoric acid were slowly added and vigorously stirred during addition with a glass rod. 3. After 2 hours, two l i t e r s of d i s t i l l e d water were added to each beaker with vigorous stirr i n g , then the mixtures were suction fi l t e r e d through five layers of cheese-cloth over two layers of Whatman No. 1 f i l t e r paper. 4. Five l i t e r s of d i s t i l l e d water were added to the acid-treated cellulose, then repeated the filter-suction as in step 3. 5. The mixture was placed in one l i t e r of 2% Na2C03 and homo-genized in Waring Blendor for 5 minutes, then stored for 12 hours. 6. The mixture was washed with five l i t e r s of d i s t i l l e d water on a suction f i l t e r , then suspended in 15 l i t e r s of d i s t i l l e d water. 7. Pelleted by centrifuge (Sorvall superspeed automatic refriger-ated centrifuge) at 8000 rpm for 10 minutes. ASSAY MEDIUM NH4H2P04, 10 g; KH2P0if-.,:, 3 g; K2HP0^, 2 g; MgS04 • 7H20, 4.45 g ; thiamine-HCl, 500 ug; yeast extract, 2.5 g; adenine, 20 mg; 139 adenosine, 40 mg; Bacto-agar, 85:. gj•:.:.acid-swbllenocellulose',25 g; (based on dry weight and used as aqueous suspension); d i s t i l l e d water, to total of 5 l i t e r s . The medium was dispensed into 18 X 150 mm Kimax culture tubes to obtain an approximately .5 - 6 .cm of opaque agar column. Tubes were autoclaved at 121°C for 15 minutes, agitated by hand and cooled perpendicu-la r l y in the ice bath. The pH of the medium was 6.0. The hyphomycetous species tested in this study were isolated from Marion Lake sediments by the modified dilution plate method (Part I, pp. 11-12). They were grown in PDA plates at 25°C. When vigorous growth was obtained, after anywhere from 3 to 20 days, agar disks were cut out of the cultures with a 12 mm cork borer, and transferred onto the acid-swollen cellulose tubes, which were incubated at 25°C. Depth of clearing was measured at weekly intervals for five weeks. Triplicate tubes were inoculated for each isolate. Attempts were made to study the effect of temperature on cellulo-l y t i c a b i l i t y by incubating at 5°C, 15°C and 25°C; in the case of incuba-tion at 5°C, tubes were kept for three months and depth of clearing in the tubes was measured again at the end of the three-month incubation. STATISTICAL TEST Analysis of variance, Tukey's and Scheffe's tests (Steel and Torrie, 1960) was performed in order to determine whether there was a difference in c e l l u l o l y t i c a b i l i t y of different isolates of the same species. RESULTS AND DISCUSSION 140 Thir.ty-two of the 36 species and variety of Hyphomycetes tested showed ce l l u l o l y t i c a b i l i t y as determined by the clearing of acid-swollen cellulose column (Table VIII and Plate X). Most of these fungi have been considered previously to be cellulose decomposers (Siu, 1951). Of these, significant clearing was observed by isolates of Gliocladium roseum, G. virens, Paecilomyces roseolus, Penicillium sp., Trichoderma hamatum, T_. koningii, T_. polysporum, _T. saturnisporum and T_. viride. The cellulo-l y t i c a b i l i t y of P_. roseolus and T\ saturnisporum is reported for the f i r s t time. It i s obvious that the strongest clearing rate was shown by species of Trichoderma which have long been demonstrated as the most active cellulose decomposers (Bisby et a l . , 1935; White et a l . , 1948; Siu, 1951; Domsch and Gams, 1969, 1972; Wood, 1969). Therefore, i t is r e a l i s t i c to believe that the increase in the numbers of isolations of Trichoderma in the f a l l and winter as observed previously (Part I) i s a reflection of their activity or at least their potential in the decomposition of cellu-lose (Pugh, 1964, 1969) in these seasons. In comparison, the depth of clearing by _T. viride (9.1 - 15 mm in 35 days) was less than that (16 mm in 35 days) obtained by Tansey (1971). The strong c e l l u l o l y t i c a b i l i t y of G. roseum was observed also by White et a l . (1948); Pugh and Dickinson (1965); Dickinson and Dooly (1969) and Domsch and Gams (1969). Although only one isolate of Penicillium sp. was tested, i t showed a moderate clearing rate (9.8 mm in 35 days) and could be considered also as an important cellulose decomposer. Some of the species do not produce clearing zones sharp enough for 141 precise measurement, e.g. Alternaria alternata, Cephalosporium acremonium, (Plate X, B) , Chrysosporium pannorum, Paecilomyces carneus, P_. terricola, Pestalotia monochaetioides, P_. truncata, P_. versicolor and Trichocladium  opacum, but the a b i l i t y to attack cellulose has been demonstrated clearly for most of them (Siu, 1951; Carmichael, 1962; Hogg and Hudson, 1966; Domsch and Gams, 1969, 1972). Cladosporium cladosporioides, Mammaria echinobotryoides, Metarrhizium anisopliae, Thysanophora penicillioides and Torulomyces lagena only formed a slight clearing zone after 3, 4 or 5 weeks of incubation, while no clearing was produced by Beauveria bassiana, Cephalosporium  incarnatum var. macrosporum, C^. khandalense, Cladosporium herbarum, C^. macrocarpum and Ve r t i c i c l a d i e l l a procera. These results may support the earlier speculation (Part I, p.129) that some of these fungal species were only temporary inhabitants of the lake sediments and may not be an impor-tant component in terms of cellulose decomposition. Despite i t s abundance in Marion Lake sediments, (?)Humicola sp. was found to be a weak cellulose decomposer (4.7 - 5.8 mm in 35 days). Table IX and Plate XI show the effects of different temperatures, 5°C, 15°C and 25°C on the c e l l u l o l y t i c a b i l i t y of fungi. The optimum temperature for the clearing of acid-swollen cellulose was 25°C for a l l the tested fungi. It is interesting to note that the depth of clearing at the end of a 3-month incubation at 5°C was more or less the same for most species as that incubation at 25°C for 35 days or less. This may indicate that there is a lag period before the attacking of cellulose by these fungi or may be simply a reflection of the effects of low temperature on metabolism. A test to compare the variation between Trichoderma hamatum and and T_. hamatum (NS) in depth, of clearing shows that there is no difference between them. This result substantiates Rifai's (1969) viewpoint that st e r i l e hyphal elongation has a doubtful taxonomic value. Generally, no significant difference in the ce l l u l o l y t i c a b i l i t y among the different isolates of the same species was detected, e.g. in Gliocladium,roseum, (?)Humicola sp., Phialophora fastigiata, Trichoderma  hamatum and Umbelopsis versiformis. Two exceptions are Trichoderma viride and T. polysporum. Considerable variation was detected which may be attributed to the heterogeneity of these species aggregates (Rifai, 1969). However, Domsch and Gams (1969) found T_. viride to be low in va r i a b i l i t y based on the cellulose activity on carboxymethyl cellulose. TABLE VIII DEPTH OF CLEARING OF ACID-SWOLLEN CELLULOSE COLUMN BY HYPHOMYCETES FROM MARION LAKE SEDIMENTS Age of Depth of Clearing (mm) Cultures Days FUNGAL NAMES (days) 7 14 21 28 35 ** Alternaria alternata (C79) 10 c c c c c Aureobasidium bolleyi (C294) 13 1.4 3.1 4.1 4.9 5.8 Beauveria bassiana (C75) 20 0 0 0 0 0 B. bassiana (C264) 20 0 0 0 0 0 B. bassiana (C293) 20 0 0 0 0 0 Cephalosporium acremonium (C18) 9 . c c c c c C. acremonium (C289) 9 c c c c c C. incarnatum var. macrosporum (C51) 13 0 0 0 0 0 C. khandalense (C86) 13 0 0 0 0 0 C. khandalense (C127) . 13 0 0 0 0 . 0 C. khandalense (C242) 13 0 0 0 0 0 Chloridium chlamydosporis (C215) 13 c 2.8 5.3 7.5 9.3 Chrysosporium pannorum (C22) 20 c c c c c Cladosporium cladosporioides (C143) 13 0 0 0 0 c C. herbarum (C146) 17 0 0 0 0 0 C. macrocarpum (C213) 13 0 0 0 0 0 Cylindrocarpon destructans (C188) 13 c 3.9 5.6 6.8 8.1 C. didymum (C153) 9 c 1.7 3.0 4.1 5.8 Gliocladium roseum (C179) 13 1.7 5.0 8.2 11.3 13.5 G. roseum (C93) 13 c 4.9 7.0 9.5 11.6 G. virens (C28) 3 2.7 5.0 8.4 10.0 12.1 Gliomastix murorum (C156) 9 0.6 1.8 3.9 5.7 7.4 (?)Humicola sp. (C214) 20 0 0.6 1.7 3.6 4.7 (?)Humicola sp. (C260) 20 0 1.1 2.6 4.8 5.8 (?)Humicola sp. (C284) 20 0 1.0 2.3 4.0 4.9 Mammaria echinobotryoides (C193) 27 0 0 c c c Metarrhizium anisopliae (106) 9 0 0 0 c c TABLE VIII —Continued Age of Cultures FUNGAL NAMES (days) 7 Metarrhizium anisopliae (C246)** 9 0 Paecilomyces carneus (C100)• 9 c P. roseolus (C99) 13 1.7 P. terricola (C115) 13 c Penicillium sp. (C258) 7 1.8 Pestalotia monochaetioides (C185) 20 c P. truncata (C184) 9 c P. versicolor (C211) 9 c Phialophora fastigiata (C245) 20 c P. fastigiata (C251) 20 c Thysanophora penicillioides (C129) 9 0 Torulomyces lagena (C259) 20 0 Trichocladium opacum (C4) 15 c Trichoderma hamatum (C326) 3 2.0 T. hamatum (C345) 3 2.5 T. hamatum(NS) (C363) 3 3.6 T. hamatum(NS) (C364) 3 3.9 T. hamatum(NS) (C365) 3 4.0 T. hamatum(NS) (C366) 3 4.3 T. hamatum(NS) (C367) 3 5.6 T. koningii (C273) 3 2.8 T. polysporum (C280) 7 2.4 T. polysporum (C336) 7 4.1 T. saturnisporum (C236) 3 3.9 T. viride (C277) 3 1.6 T. viride (C278) 3 1.9 T. viride (C358) 3 2.0 T. viride (C359) 3 1.1 T. viride (C361) 3 2.5 Depth of Clearing * (mm) Days 14 21 28 35 0 c c c c c c c 5.0 7.0 9.8 11.3 c c c c 4.5 6.6 8.3 9.8 c c c c c c c c c c c c 2.0 2.9 3.8 4.6 1.8 2.7 3.8 4.5 0 0 c c 0 0 0 c c c c c 5.4 9.0 12.5 15.8 6.3 9.6 12.5 15.0 7.9 11.7 15.5 19.0 7.8 11.6 14.7 17.6 8.5 11.8 15.5 18.5 8.9 13.3 17.2 20.6 10.3 13.9 17.1 20.5 7.0 10.3 13.2 15.3 4.9 7.0 9.1 14.3 7.6 9.7 12.4 20.8 7.2 10.7 13.3 16.0 4.3 7.1 9.1 11.0 5.4 9.0 11.7 15.0 5.2 7.6 9.6 11.3 2.3 4.9 7.0 9.1 6.3 9.2 11.8 13.8 TABLE VIII —Continued FUNGAL NAMES Umbelopsis versiformis (C191) U. versiformis (C287) U. versiformis (C288) U. versiformis (C328) Verticicladiella procera (C128) Age of Cultures (days) 7 13 c 13 c 13 c 13 c 20 0 •k* C Average of three replicates. Author's stock culture numbers. Definite clearing, but not sharp enough for measurement Depth * of Clearing (mm) Days 14 21 28 35 0.8 1.4 2.0 2.9 0.2 0.8 2.0 2.5 0.7 1.8 3.3 3.9 0.3 1.0 2.0 2.8 0 0 0 0 PLATE X Composite plate showing depth of .clearing- of acid-swollen cellulose column by Trichoderma saturnisporum (A) and Cephalosporium acremonium (B). From l e f t to right, control, 7, 14, 21, 28 and 35 days incubation. 1 4 7 PLATE X TABLE IX DEPTH OF CLEARING OF ACID-SWOLLEN CELLULOSE COLUMN BY HYPHOMYCETES FROM MARION LAKE SEDIMENTS AT 5°C, 15°C and 25°C FUNGAL NAMES Gliocladium roseum (C179) (?)Humicola sp. (C214) Trichoderma hamatum (C345) Trichoderma polysporum (C336) Trichoderma viride (C358) Age of Cultures (days) 13 20 3 3 3 Incubation Temp (°C) Depth of Clearing (mm) lerature Days Months 7 14 21 28 35 3 25 1.7 5.0 8.2 11.3 13.5 -15 c 3.7 5.8 7.6 9.6 -5 0 . 0 0 " 0 c 7.0 25 0 0.6 1.7 3.6 4.7 -15 0 0.2 1.2 2.4 3.5 -5 0 0 0 0 0 4.9 25 2.5 6.3 9.6 12.5 15.0 -15 1.6 4.2 7.8 10.3 13.3 -5 0 0 0 c 4.0 13.5 25 4.1 7.6 9.7 12.4 20.8 -15 2.1 5.8 8.3 10.3 13.8 -5 0 0 2.8 4.5 6.3 14.6 25 2.0 5.2 7.6 9.6 11.3 -15 1.0 3.7 5.9 8.4 10.5 -5 0 0 0 0 c 8.8 * Average of three replicates. ** Author's stock culture numbers. - Not measured. c Definite clearing, but not sharp enough for measurement. -p-co PLATE XI Composite plate showing depth of clearing of acid-swollen cellulose column by Trichoderma viride at 25°C (A) , 15°C (B) and 5°C (C) , From l e f t to right, control, 7, 14, 21, 28 and 35 days incubation. P L A T E X I 150 151 PART III PRELIMINARY STUDY OF FUNGAL ACTIVITY IN SITU BASED ON THE OBSERVATION OF DECOMPOSITION OF BURIED CELLOPHANE IN MARION LAKE MUDS As seen in Parts I and II of the present study, a sizable and diverse population of Hyphomycetes (p. 110) was isolated from Marion Lake sediments and most of them showed c e l l u l o l y t i c a b i l i t y as determined by the clearing of acid-swollen cellulose columns (p. 140). Pugh (1964) noted "... the ab i l i t y of a fungus to decompose cellulose in the laboratory indicates that i t must possess at least the potential to decompose this substrate in the s o i l , ... and not necessarily the actual fungal activity at the time of sampling because there is no indication whether the isolates obtained are active in the s o i l or merely passive propagules". Neverthe-less, as mentioned previously, Cooke (1961) postulated that geofungi are permanent and significant members of aerobic aquatic habitats, a point further stressed by Kaushik and Hynes (1971) and Park (1972). Therefore, the next stage of this study was an in situ experiment designed to assess the importance of these geofungi in their natural environment. In other words, the aim of the experiment was to examine whether geofungi isolated from Marion Lake muds are active in the decomposition of cellulose or whether they exist only as inactive propagules. It also should enable one to detect which organisms - fungi, bacteria, actinomycetes or animals decompose cellulose in lake muds. HUGHES-CHANG SAMPLING COLUMN AND TECHNIQUE A sampling column, constructed from plexiglas tubing, was designed to hold standard microscope slides with attached cellophane films in lake muds. The detailed design of the column w i l l be described elsewhere. 152 Basically, i t consists of five chambers, each chamber holding one standard microscope slide in vertical position. The technique used was that of Tribe (1957). The cellophane films, 1.0 X 1.0 cm, were boiled in d i s t i l l e d water to remove plasticizers. After autoclaving, two wet cellophane films were placed side by side on an alcohol-sterilized microscope slide. Excess water was drained off. The cellophane-covered slides were then put into the chambers of the sampling column, with cellophaned edges on the top. The sampler was buried v e r t i -cally in the lake sediment, with the upper 1 cm of the column protruding above the mud surface. Nine columns were buried in muds near Station 3 (the deeper-water station) in April, 1972. One of these columns was re-trieved every month from the muds; the cellophane films were recovered, washed in st e r i l e d i s t i l l e d water several times, and then examined. This study lasted for six months, from April to October, 1972, although no column was recovered in August, 1972. One d i f f i c u l t y encountered was that some of the cellophane films did not adhere to the slides after the f i r s t month. Fortunately, they were recovered inside the column chambers. Thus, i t seems l i k e l y that a special binding agent may be necessary to cement cellophane films to the slides in such studies, as suggested by Golley (1960). The following observations were carried out: Microscopical Examination Two cellophane films were stained in picronigrosin in lactophenol (Smith, 1954) for an hour, followed by washing and mounting in lactophenol, Cellophane PT 220 was kindly supplied by TCF of Canada Limited. PT 220 is a direct equivalent to British Cellophane Limited's PT 300, used by Tribe (1957). 153 then sealed with co l o u r l e s s n a i l varnish. Observations 1st month (May, 1972): A l l the cellophane films recovered were i n t a c t . Various b a c t e r i a l forms, mostly rods were observed. Segments of dark mycelium also were present. 2nd month (June, 1972): Cellophane f i l m s were more or l e s s the same as those c o l l e c t e d i n May, 1972. However, bacteria were s l i g h t l y more abundant and incurved c e l l s , probably Cytophaga could be seen. There were also a few f i n e filaments. 3rd month (July, 1972): Bacteria of rod and coccoid forms, Cytophaga, and f i n e filaments densely covered the cellophane f i l m s which were eaten o f f s l i g h t l y at the corner. An i n t e r e s t i n g feature at t h i s stage was the presence of ch y t r i d s , notably Nowakowskiella spp. and Kar1ingiomyces marHandicus (Karling) Sparrow. Occasionally, fan-shaped growths were observed which were described as "rooting branches" by Tribe (1957). These f a n - l i k e fungi may belong to the genera A l t e r n a r i a , Botryotrichum, Cephalosporium, Chaetomium, Doratomyces, Fusarium, Gliocladium, Humicola, Monilia, P e n i c i l l i u m , R h i z o p h l i c t i s , Stachybotrys, Staphylotrichum, Trichoderma and Mycelia S t e r i l i a (Tribe, 1957, 1960a, 1960b; Went, 1959; Went and de Jong, 1966). 5th month (Sept., 1972): The cellophane f i l m s recovered were very soft and e a s i l y broken into pieces when touched; while some had already disintegrated. Microscopic observation showed various b a c t e r i a l forms and Cytophaga c e l l s , although they were les s abundant than that of 3rd-month f i l m . The cellophane f i l m s were colonized by fan-shaped rooting fungi and c h y t r i d s . Occasionally, holes were seen which may have resulted from the enzymic action of the fungi (Tribe, 1960b) or the attack of cellophane 154 by small animals (Went and de Jong, 1966). Various conidia, mostly oval and smooth also could be detected. 6th month (Oct., 1972): The breakdown of cellophane was almost completed. Small broken pieces of cellophane were overgrown by fungal mycelium and by bacteria, to a less extent. Abundant hyaline and some dark conidia were present. Unfortunately, i t is not possible to identify these fungi on the basis of conidia alone. During the course of examina-tion, dark mycelial segments were seen from time to time, however, they were most abundant in this observation. Faecal pellets and legs of s o i l animals also were seen. Isolation of Microorganisms on Buried Cellophane Films After washing in sterile d i s t i l l e d water, the cellophane films collected each month, were cut into small pieces and plated on Czapek Solution Agar, 2% Malt Agar and Potato Dextrose Agar as used in Part I (pp. 11-12), then incubated at 25°C. Table X l i s t s the microorganisms isolated from the cellophane. No quantitative analysis was attempted. The origin of fungi isolated was not traced. It was noticed that in the last samples (i.e. Oct., 1972), many hyphae were evident on the disintegrated cellophane pieces under micro-scope, yet they yield no growth after being transferred onto agar media. The overall result showed that Hyphomycetes isolated were those recorded as dominant ones in Part I (p. 110), for example, (?)Humicola sp., Penicillium spp., Trichoderma spp., and Mycelia S t e r i l i a ; species which were shown also to have c e l l u l o l y t i c a b i l i t y (Part II, Table VIII). TABLE X MICROORGANISMS ISOLATED FROM BURIED CELLOPHANE FILMS PLATED ON CZAPEK SOLUTION AGAR, 2% MALT AGAR AND POTATO DEXTROSE AGAR, APRIL TO OCTOBER, 197 2. Buried Period (months) 1 2 Isolation Date May, 1972 June, 1972 July, 1972 Sept., 1972 Oct., 1972 Microorganisms Isolated Bacteria and Dark Mycelia S t e r i l i a Bacteria, Hyaline and Dark Mycelia S t e r i l i a , Gliocladium roseum, (?)Humicola sp., Penicillium spp., Phialophora fastigiata, Trichoderma hamatum(NS). T. polysporum, T. viride Bacteria, Hyaline and Dark Mycelia S t e r i l i a , Penicillium spp., Streptomyces sp., Trichoderma hamatum(NS), T. polysporum, T. viride Bacteria, Cytophaga, Cephalosporium acremonium, (?)Humicola sp., Hyaline and Dark Mycelia S t e r i l i a , Penicillium spp., Streptomyces sp., Trichoderma hamatum(NS), T. viride Bacteria, Cytophaga, (?)Humicola sp., Umbelopsis versiformis t-1 156 Scanning Electron Microscopy The technique described by Higham and Bisalputra (1970) was adapted for these examinations. After washing in st e r i l e d i s t i l l e d water, cellophane films were freeze-dried for 24 hours at -40°C in a Speedivac Pearse Tissue Dryer model 1. The dried films were then mounted on specimen stubs and coated with gold. Observations of the material were made with a Cambridge Stereoscan Electron Microscope at an accelerating voltage of 20 kV. Observations 1st and 2nd months (May and June, 1972): Only a few bacterial cells and some amorphous bodies were seen. 3rd month (July, 1972): The cellophane film was covered densely with fine filaments of less than 1 y thick. Bacterial cells lay scattered. 5th month (Sept., 1972): The fine filaments and fungal hyphae enmeshed the partially, disintegrated cellophane films. 6th month (Oct., 1972): Broken pieces,of cellophane were covered very well by fungal hyphae. Bacterial cells were shown to associate with fungal hyphae occasionally. Particular attention was drawn to the slightly curved grooves which are similar to the size and shape of Cytophaga. This confirms the observation and suggestion of Went and de Jong (1966) that Cytophaga is responsible for the transparent areas the size and form of which are reminiscent of the organism i t s e l f , and the decomposition of cellophane by Cytophaga is a direct-contact attack. CONCLUSION The course of cellulose decomposition in lake muds, based on breakdown of cellophane as observed by direct microscopy, cultural isolation and Scanning Electron Microscopy agrees with the sequence 157 described by Tribe (1957) in soils. Tribe noted two main phases, fungal and bacterial during the decomposition of cellophane in the s o i l . Fre-quently actinomycetes and fungi are the f i r s t colonizers, and are / followed by a bacterial stage which may continue indefinitely (Tribe, 1957; Golley, 1960; Harding, 1967). Among fungi, chytrids may be considered as pioneer decomposers. The entire (or nearly so) cellophane samples, from which scattered bacterial cells were recovered in the f i r s t two months, seem to suggest that although bacteria were present before or in the early fungal phase, they were not responsible for much decomposition. After fungal growth, the cellophane disintegrated quickly. This may indicate that in the process of cellophane decomposition, fungi are more important than bacteria or actinomycetes as reported by Kaushik and Hynes (1968, 1971) and Barlocler and Kendrick (1973) in the breakdown of leaves. At the later stage of decomposition, mycelium becomes moribund and bacteria develop over i t (Tribe, 1960a). This in turn supports a population of nematodes and other small animals. Although the moribund mycelium stage was not observed in the present study, failure in isolating fungi from the last sample period may be a reflection of i t s existence. The organisms isolated from the cellophane, except for the unidentified bacteria, are known usually as cellulose decomposers (Skinner and Mellem, 1944; Siu, 1951; Went and de Jong, 1966; Malik and Eggins, 1970; Chang, 1974, this thesis). This preliminary study also substantiates the value of using Scanning Electron Microscope for studies on s o i l microorganisms, notably their activity ±n situ and relationships with their natural environments (Gray, 1967; Parkinson, 1973). However, further investigation i s neces-sary to overcome certain limitations of this technique, particularly in 158 view of the i m p o s s i b i l i t y to prove the i d e n t i t y of f i n e filaments, coarse mycelium, conidia and b a c t e r i a l c e l l s . In s p i t e of i t s preliminary nature t h i s experiment has shown that geofungi i n the lake muds are an important component in the decomposition of c e l l u l o s e as measured by the breakdown of cellophane. Of course, i t i s an i n e v i t a b l e f a c t that cellophane i s a thinner and more simple form of c e l l u l o s e than those forms occurring i n nature, e.g. plant residues and lea f l i t t e r . Nevertheless, the study on cellophane serves as an i n i t i a l i n d i c a t o r . In a future study, either whole or thi n sections of natural substrates such as twigs or leaves should be used. A longer period of decomposition and a more various and complex i n t e r a c t i o n of microorganisms w i l l be expected undoubtedly. Yet, a s i m i l a r a s s o c i a t i o n of organisms leading to the decomposition of these natural substrates as that of cellophane also might be anticipated (Tribe, 1960b). 159 LITERATURE CITED Alexander, M. 1961. Introduction to s o i l microbiology. John Wiley & Sons, Inc., New York. 472 pp. Anastasiou, C. J. 1964. Some aquatic Fungi Imperfecti from Hawaii. Pacific Sci., 18: 202-206. Arx, J. A. von 1970. The genera of fungi sporulating in pure culture. J. Cramer, Lehre. 288 pp. Balasooriya, I. and D. Parkinson. 1967. Studies on fungi in a pine-wood s o i l . II. Substrate relationships of fungi in the mineral horizons of the s o i l . Rev. Ecol. Biol. Sol., 4_: 639-643. Barlocher, F. and B. Kendrick. 1973. Fungi in the diet of Grammarus  pseudolimnaeus (Amphipoda). Oikos, 24_: 295-300. Barnett, H. L. and B. B. Hunter. 1972. Illustrated genera of Imperfect Fungi. 3rd. ed. Burgess Publishing Company, Minneapolis, Minn.. 241 pp. Barron, G. L. 1962. New species and new records of Oidiodendron. Can. J. Bot., 40: 589-607. 1967. Torulomyces and Mono c i l l ium. Mycologia, _59_: 716-718. 1968. The genera of Hyphomycetes from s o i l . The Williams & Wilkins Company, Baltimore, Md.. 364 pp. Batista, A. C., A. A. Machado and H. da S. Maia. 1961. Phaeofabrea  parahybensis n. sp. e outros fungos sobre Nectandra sp., Publ. Inst. Micol. Recife (Brazil), 302: 1-28. Benham, R. W. and J. L. Miranda. 1953. The genus Beauveria, morphological and taxonomical studies of several species and of two strains isolated from wharf-piling borers. Mycologia, 4_5: 727-746. Bertoldi, M. de, A. A. Lepidi and M. P. Nuti. 1972. Classification of the genus Humicola Traaen. I. Preliminary reports and investigations. Mycopath. Mycol. Appl., 46: 289-304. and 0. Verona. 1970. Microfungi new or uncommon in Italy isolated from s o i l in Sardinia. L'Agric. I t a l . , 7_0_: 349-370. Bhatt, G. C. 1965. Studies on the fungal flora of cedar forests. M. Sc. thesis, Dept. of Bot., Univ. of Guelph, Ontario. 77 pp. ' 1970. The s o i l microfungi of white cedar forests in Ontario. Can. J. Bot., 48: 333-340. Bisby, G. R. 1938. The fungi of Manitoba and Saskatchewan. National Research Council of Canada, Ottawa. 189 pp. , N. James and M. I. Timonin. 1933. Fungi isolated from Manitoba s o i l by the plate method. Can. J. Res. C, £5: 253-275. , M. I. Timonin and N. James. 1935. Fungi isolated from s o i l profiles in Manitoba. Can. J. Res. C, L3: 47-65. Black, C. A. e_t a l . 1965. Methods of s o i l analysis. II. Chemical and microbiological properties. Amer. Society of Agronomy, Inc., Madison, Wisconsin. 1572 pp. Booth, C. 1966. The genus Cy1indrocarpon. Mycol. paper No. 104, Commonwealth Mycological Institute, Kew, England. 56 pp. Booth, T. 1969. Marine fungi from British Columbia: monocentric chytrids and chytridiaceous species from coastal and interior halomorphic soils. Syesis, 2} 141-161. Borut, S. Y. 1960. An ecological and physiological study on s o i l fungi of the Northern Negev (Israel). Bull. Res. Coun. Israel, 8D: 65-80. Brandsberg, J. W. 1969. Fungi isolated from decomposing conifer l i t t e r . Mycologia, 61: 373-381. i Brewer, D. 1958. Studies on slime accumulations in pulp and paper mills. I. Some fungi isolated from mills in New Brunswick and Newfoundland. Can. J. Bot., 36: 941-946. 1959. Studies on slime accumulations in pulp and paper mills. II. Physiological studies of Phialophora fastigiata and P_. richardsiae. Can. J. Bot., 37_: 339-343. Brown, A. H. S. and G. Smith. 1957. The genus Paecilomyces Bainier and i t s perfect stage Byssochlamys Westling. Trans. Brit. Mycol. Soc, 40: 17-89. Brown, J. C. 1958. Soil fungi of some British sand dunes in relation to s o i l type and succession. J. Ecol., 4_6: 641-664. Burges, A. and D. P. Nicholas. 1961. Use of s o i l sections in studying amount of fungal hyphae. Soil Sci., 92: 25-29. Butler, E. E. and L. J. Petersen. 1972. Endomyces geotrichum, a perfect state of Geotrichum candidum. Mycologia, .54_: 365-374. Carmichael, J. W. 1957. Geotrichum candidum. Mycologia, _+9_: 820-830. 1962. Chrysosporium and some other aleuriosporic Hyphomycetes. . Can. J. Bot., 40: 1137-1173. Chesters, C. G. C. 1948. A contribution to the study of fungi in the s o i l . Trans. Brit. Mycol. Soc, 30: 100-117. 161 Chesters, C. G. C. 1949. Concerning fungi inhabiting s o i l . Trans. Brit. Mycol. Soc, 32: 197-216. Chou, C. K. and R. C. Stephen. 1968. Soil fungi: Their occurrence, distribution and association with different microhabitats together: with a comparative study of isolation technique. Nova Hedwigia, 15: 393-409. Christensen, M., W. F. Whittingham and R. 0. Novak. 1962. The s o i l microfungi of wet-mesic forests in southern Wisconsin. Mycologia, 54: 374-388. Cobb, M. J. 1932. A quantitative study of the microb_ganic.-population_ of a hemlock and a deciduous forest s o i l . Soil Sci., _33_: 325-345. Cole, G. T. and B. Kendrick. 1973. Taxonomic studies of Phialophora. Mycologia, 65_: 661-688. Collins, V. G. and L. G. Willoughby. 1962. The distribution of bacteria and fungal spores in Blelham Tarn with particular reference to an experimental overturn. Archiv. fur Mikrobiologie, 43_: 294-307. Cooke, W. B. 1958. The ecology of the fungi. Bot. Rev., 24: 341-429. 1961. Pollution effects on the fungus population of a stream. Ecology, 42: 1-18. 1968. Some fungi of the Cache l a Poudre River, Colorado. Mycopath. Mycol. Appl., _3_5: 361-372. Dayal, R. and 0. S. D. Gupta. 1967. The s o i l fungi of Varanasi (India) in relation to the edaphic factors. Oikos, 18_: 76-81. Dick, M. W. 1963. The occurrence and distribution of Saprolegniaceae in certain soils of south-east England. III. Distribution in relation to pH and water content. J. Ecol., _51: 75-81. 1966. The Saprolegniaceae of the environs of Blelham Tarn: Sampling techniques and the estimation of propagule numbers. J. Gen. Microbiol., 42: 257-282. 1970. Saprolegniaceae on insect exuviae. Trans. Brit. Mycol. Soc, 55: 449-458. 1971. The ecology of Saprolegniaceae in lentic and l i t t o r a l muds with a general theory of fungi in the lake ecosystem. J. Gen. Microbiol., 65: 325-337. and H. V. Newby. 1961, The occurrence and distribution of Saprolegniaceae in certain soils of south-east England. I. Occurrence. J. Ecol., 49: 403-410. 162 Dickinson, C. H. 1968. Gliomastix Gueguen. Mycol. paper No. 115, Commonwealth Mycological Institute, Kew, England. 24 pp. and M. Dooley. 1969. Fungi associated with Irish peat bogs. Proc. Roy Irish Acad. B, §8: 109-137. Domsch, K. H. and W. Gams. 1969. Variability and potential of a s o i l fungus population to decompose pectin, xylan and carboxymethyl cel l u -lose. Soil Biol. Biochem., 1: 29-36. 1972. Fungi in agricultural soils. Longman Group Limited, London. (Translation by P. S. Hudson of "Pilze aus Agrarboden", 1970) 290 pp. Dube, H. C. and K. S. Bilgrami. 1966. Pestalotia or Pestalotiopsis? Mycopath. Mycol. Appl., 2_9_: 33-54. Dubos, R. J . 1928. The influence of environmental conditions on the act i v i t i e s of cellulose decomposing fungi in the s o i l . Ecology, 9: 12-27. Efford, I. E. 1967. Temporal and spatial differences in phytoplankton productivity in Marion Lake, British Columbia. J. Fish. Res. Bd. Canada, 24: 2283-2307. 1970. An interim review of the Marion Lake project. In "Proceedings of the IBP-UNESCO". Symposium on Productivity Problems of Freshwaters, Poland. Z. Kajak ed. pp. 89-109. Eggins, H. 0. W. and G. J . F. Pugh. 1962. Isolation of cellulose-decomposing fungi from the s o i l . Nature, 193: 94-95. E l l i s , M. B. 1965. Dematiaceous Hyphomycetes VI. Mycol. paper No. 103, Commonwealth Mycological Institute, Kew, England. 46 pp. 1966. Dematiaceous Hyphomycetes. VII. Culvularia, Brachysporium etc.. Mycol. paper No. 106, Commonwealth Mycological Institute, Kew, England. 57 pp. 1971. Dematiaceous Hyphomycetes. Commonwealth Mycological Institute, Kew, England. 608 pp. Fassatiova, 0. 1967. Notes on the genus Humicola. II. Ceska Mykol., 21: 78-89. Fergus, C. L. 1969. The c e l l u l o l y t i c activity of thermophilic fungi and actinomycetes. Mycologia, _61: 120-129. Fraker, P. 1971. Bacteria in the mud. In "Marion Lake Project Report, 1970-1971, IBP". Institute of Resource Ecology, TJ.B.C. pp. 19-23. Gams, W. 1970. Cephalosporlumbartige Schimmelpilze (Hyphomycetes). G. Fischer, Stuttgart. 262 pp. 163 Gams, W. and K. H. Domsch. 1969. The spatial and seasonal distribution of microscopic fungi in arable soils. Trans. Brit. Mycol. Soc, 52: 301-308. Garrett, S. D. 1951. Ecological groups of s o i l fungi: A survey of substrate relationships. New Phytol., _50: 149-166. 1956. Biology of root infecting fungi. Cambridge University Press. 293 pp. 1963. Soil fungi and s o i l f e r t i l i t y . The MacMillan Company, New York. 165 pp. Gilman, J. C. 1957. A manual of s o i l fungi. 2nd. ed. The Iowa State College Press, Ames, Iowa. 450 pp. Gochenaur, S. E. 1964. The s o i l microfungi of willow-cottonwood forests in southern Wisconsin. Ph.D. thesis, Univ. of Wisconsin, Wisconsin. 316 pp. and M. P. Backus. 1967. Mycoecology of willow and cottonwood lowland communities in southern Wisconsin. II. Soil microfungi in the Sand-Bar Willow stands. Mycologia, 59: 893-901. and W. F. Whittingham. 1967. Mycoecology of willow and cotton-wood lowland communities in southern Wisconsin. I. Soil microfungi in the willow-cottonwood forests. Mycopath. Mycol. Appl., 33: 125-139. Golley, F. B. 1960. An index to the rate of cellulose decomposition in the s o i l . Ecology, 41_: 551-552. Goos, R. D. 1963. Further observations on s o i l fungi in Honduras. Mycologia, 55: 142-150. Gray, P. H. H. and N. B. McMaster. 1933. A microbiological study/of podsol s o i l profiles. Can. J. Res. C, jJ: 375-389. and C. B. Taylor. 1935. A microbiological study of podsol s o i l profiles. II. Laurentian soils. Can. J. Res. C, 13: 251-255. Gray, T. R. G. 1967. Stereoscan electron microscopy of s o i l micro-organisms. Science, 155: 1668-1670. Gr i f f i n , D. M. 1972. Ecology of s o i l fungi. Chapman and Hall Ltd., London. 193 pp. Guba, E. F. 1955. Monochaetia and Pestalotia. Mycologia, 47: 920-921. 1956. Monochaetia and Pestalotia vs. Truncatella, Pestalotiopsis and Pestalotia. Ann. Microbiol., ]_: 74-76. 164 Guba, E. F. 1961. A monograph of Monochaetia and Pestalotia. Harvard University Press, Cambridge, Massachusetts. 342 pp. Hammill, T. M. 1970. Paecilomyces clavisporis sp. nov., Trichoderma saturnisporum sp. iiov., and other noteworthy s o i l fungi from Georgia. Mycologia, 62: 107-122. 1972. Fine structure of annellophores. HI, Monotosporella sphaerocephala. Can. J. Bot., \50: 581-585. Harding, D. J. L. 1967. Faunal participation in the breakdown of cello-phane inserts in the forest floor. ' In "Progress in Soil Biology". 0. Graff and J. E. Satchell ed. North-Holland Publishing Company, Amsterdam, pp. 10-20. Harrison, M. J., R. T. Wright and M. Y. Richard. 1971. Method for measuring mineralization in lake sediments. Appl. Microbiol., 21: 698-702. Hashmi, M. H., B. Kendrick and G. Morgan-Jones. 1972. Conidia ontogeny in Hyphomycetes: The genera Torulomyces Delisch and Monocillium Saksena. Can. J. Bot., 50: 1461-1463. Hedrick, L. R. and M. Soyugenc. 1967. Yeasts and molds in water and sediments of Lake Ontario. Proc. 10th Conf. Great Lakes Res., : 20-30. , W. Cook and L. Woollett. 1968. Yeasts and molds in Lake Superior water and some of i t s tributaries. Proc. 11th Conf. Great Lakes Res., : 538-543. Henis, Y., P. Keller and A. Keynan. 1961. Inhibition of fungal growth by bacteria during cellulose-decomposition. Can. J. Microbiol., - 7_: 857-863. Hennebert, G. L. 1968. Echinobotryum, Wardomyces and Mammaria. Trans. Brit. Mycol. Soc, 5J.: 749-762. Henrici, A. T. 1939. The distribution of bacteria in lakes. In "Problems of Lake Biology". F. R. Moulton ed. Publ. Amer. Assoc. Adv. Sci., No. 10, Washington, D.C. pp. 39-64. Higham, M. T. and T. Bisalputra. 1970. A further note on the surface structure of Scenedesmus coenobium. Can. J. Bot., 48_: 1839-1841. Hodges, C. S. 1962. Fungi isolated from southern forest tree nursery soils. Mycologia, 54^ 221-229. Hogg, B. M. and H. J. Hudson. 1966. Microfungi on leaves of Fagus sylyatica. I. The microfungal succession. Trans. Brit. Mycol. Soc, 49: 185-192. 165 Hoog, G. S. de 1972. The genera Beauveria, Isaria, Tritifachium and Acrodontium gen. nov.. Studies in Mycology No. 1, Centraalbureau voor Schimmelcultures, Baarn. 41 pp. Hudson, H. J. and C. T. Ingold. 1960. Aquatic Hyphomycetes from Jamaica. Trans. Brit. Mycol. Soc, 43: 469-478. Hughes, G.C. 1969. Marine fungi from British Columbia: Occurrence and distribution of lignicolous species. Syesis, 2} 121-140. Hughes, S. J. 1951. Studies on microfungi. XI. Some Hyphomycetes which produce phialides. Mycol. paper No. 45, Commonwealth Mycological Institute, Kew, England. 36 pp. 1952. Trichocladium Harz. Trans. Brit. Mycol. Soc, 35: 152-157. 1955. Microfungi. I. Cordana, Brachysporium, Phragmocephala. Can. J. Bot., 33: 259-268. 1957. Microfungi. III. Mammaria Cesati. Sydowia Beih., 1: 359-363. Ingold, C. T. 1942. Aquatic Hyphomycetes of decaying alder leaves. Trans. Brit. Mycol. Soc, 25: 339-417. 1949. Aquatic Hyphomycetes from Switzerland. Trans. Brit. Mycol. Soc, 32: 341-345. 1956. Stream spora in Nigeria. Trans. Brit. Mycol. Soc, 39: 108-110. 1958. Aquatic Hyphomycetes from Uganda and Rhodesia. Trans. Brit. Mycol. Soc, 41: 109-114. 1960. Aquatic Hyphomycetes from Canada. Can. J. Bot., 38: 803-806. Is h i i , H. 1969. Studies on the distribution of microfungi in pine forest s o i l . VI. Seasonal fluctuations of microfungi in the organic horizon. Bull. Fac Agric. Shimane Univ. , Japan, 3_: 17-20. Iterson, G. van 1904. Die Zersetzung von Cellulose durch aerobe Mikroorganismen. Zentbl. Bakt. Parasitkde (Abt. II), 11_: 689-698. Jensen, H. L. 1931. The fungus flora of the s o i l . Soil Sci., 31: 123-158. ' 1934. Contributions to the microbiology of Australian soils. I. Numbers of microorganisms in s o i l and their relation to certain external factors. Proc Linnean Soc. N.S.W., 59: 101-117. 166 Johnson, L. F. and E. A. Curl. 1972. Methods for research on the ecology of soil-borne plant pathogens. Burgess Publishing Co., Minnesota. 247 pp. Kamal and K. S. Bhargava. 1970. Studies on s o i l fungi from teak forests of Gorakhpur. VI. A study on p e n i c i l l i a from three teak stands of different ages. Proc. Nat. Acad. Sci. (India), B (Biol. Sci.), 40: 191-194. Kaushik, N. K. and H. B. N. Hynes. 1968. Experimental study on the role of autumn-shed leaves in aquatic environments. J. Ecol., \56: 229-243. 1971. The fate of the dead leaves that f a l l into streams. Arch. Hydrobiol. , 68^: 465-515. Kendrick, W. B. 1,961. Hyphomycetes of conifer leaf l i t t e r : Thysanophora gen. nov.. Can. J. Bot., 39: 817-832. 1962. Soil fungi of a copper swamp. Can. J. Microbiol., 8: 639-647. and G. C. Bhatt. 1966. Trichocladium opacum. Can. J. Bot., 44: 1728-1730. and N. A. Burges. 1962. Biological aspects of the decay of Pinus sylvestris leaf l i t t e r . Nova Hedwigia, _+_: 313-342. MacLeod, D. M. 1954. Investigations in the genera Beauveria V u i l l . and Tritirachium Limber. Can. J. Bot., 32_: 818-890. Malik, K. A. and H. 0. W. Eggins. 1970. A perfusion technique to study the fungal ecology of cellulose deterioration. Trans. Brit. Mycol. Soc., 54: 289-301. Martin, J. P. and D. G. Aldrich. 1954. Effect of various exchangeable cation ratios on kinds of fungi developing during decomposition of organic residues in s o i l . Soil Sci. Soc. Am. Proc., JJB: 160-164. Mason, E. W. 1941. Annotated account of fungi received at the Imperial Mycological Institute. List II, Fasc. 3 (special part). Mycol. paper No. 5, Commonwealth Mycological Institute, Kew, England. 67 pp. Mathews, R. W. 1973. A palynological study of postglacial vegetation changes in the University Research Forest, southwestern British Columbia. Can. J. Bot., 51: 2085-2103. Matsushima, T. 1971. Microfungi of the Solomon Islands and Papua-New Guinea. Shionogi Research Lab., Shionogi & Co. Ltd., Japan. 78 pp. Matturi, S. T. and H. Stenton. 1964. Distribution and status in the so i l of Cyl indrocarpon species. Trans. Brit. Mycol. Soc, 47: 577-587. 167 McBeth, I. G. 1916. Studies on the decomposition of cellulose in soils. Soil Sci., 1: 437-487. McLennan, E. I. and S. C. Ducker. 1954. The ecology of the s o i l fungi of an Australian Heathland. Aust. J. Bot., 2_: 220-245. Mehrotra, B. R. and R. K. Kakkar. 1972. Ecological study of s o i l fungi of an agricultural f i e l d in Allahabad. Mycopath. Mycol. Appl., 47: 41-58. Melin, E. and J. A. Nannfeldt. 1934. Researches into the blueing of ground wood pulp. Svenska Skogsvardsforen. Tidskr., 32_: 397-616. Meyers, S. P. and R. T. Moore. 1960. Thalassiomycetes II. New genera and species of Deuteromycetes. Amer. J. Bot., 4_7: 345-349. Miller, J. H., J. E. Giddens and A. A. Foster. 1957. A survey of the fungi of forest and cultivated soils of Georgia. Mycologia, 49: 779-808. Mishra, R. R. 1965. Seasonal distribution of s o i l fungal population in four different grass consociation. Trop. Ecol., 6\ 133-140. 1966a. Influence of s o i l environment and surface vegetation on so i l mycoflora. Proc. Nat. Acad. Sci. (India), B, 3j5: 117-123. 1966b. Seasonal variation in fungal flora of grasslands of Varanasi (India). Trop. Ecol., ]_: 100-113. 1972. Aeromycology of Gorakhpur. IV. Periodical fluctuation of aerospora. Mycopath. Mycol. Appl., 48^ : 213-222. and V. B. Srivastava. 1970. Air mycoflora of a lake and an adjacent f i e l d of Gorakhpur. Indian J. Microbiol., ]_0: 39-44. Montegut, S. 1960. Value of the dilution method. In "Ecology of Soil Fungi". An International Symposium. D. Parkinson and J. S. Waid ed. Liverpool University Press, pp. 43-52. Morrall, R. A. A. 1968. Two new species of Oidiodendron from boreal forest soils. Can. J. Bot., 46j 203-206. and T. C. Vanterpool. 1968. The s o i l microfungi of upland boreal-forest at Candle Lake, Saskatchewan. Mycologia, 6^0: 642-654. Moubasher, A. H. and S. M. El-Dohlob. 1970. Seasonal fluctuations of Egyptian s o i l fungi. Trans. Brit. Mycol. Soc. , 54_: 45-51. Mueller, G. 1964a. Die Gattung Sporotrichum Link. Eine taxonomische und morphologische Studie der bei Mensch und Tier vorkommen den Spezies. T e i l I. Wiss. Humboldt - Univ. Berlin, Math.-Nat. R., 13: 611-638. 168 Mueller, G. 1964b. Die Gattung Sporotrichum Link. T e i l II. Wiss. Humboldt - Univ. Berlin, Math.-Nat. R., 13_: 843-860. 1965. Die Gattung Sporotrichum Link. T e i l III. Ibid., 14: 753-798. Nilsson, S. 1958. On some freshwater Swedish Hyphomycetes. Svensk Bot. Tidskr., 52: 291-318. 1962. Second note on Swedish freshwater Hyphomycetes. Bot. Notiser, 115: 73-86. 1964. Freshwater Hyphomycetes. Symb. Bot. Upsal., 18: 1-130. Norkrans, B. 1967. Cellulose and Cellulolysis. In "Advances in Applied Microbiology". Vol. 9. W. W. Umbriet ed. Academic Press, New York, pp. 91-130. Omvik, A. 1955. Two new species of Chaetomium and one new Humicola sp.. Mycologia, 47_: 748-757. Onions, A. H. S. and G. L. Barron. 1967,. Monophialidic species of Paecilomyces. Mycol. paper No. 107, Commonwealth Mycological Institute, Kew, England. 25 pp. Park, D. 1963. The presence of Fusarium oxysporum in soils. Trans. Brit. Mycol. Soc, 46: 444-448. 1968. The ecology of terrestrial fungi. In "The Fungi. III. The Fungal Population". G. C. Ainsworth and A. S. Sussman ed. Academic Press, New York. pp. 5-39. 1972. Methods of detecting fungi in organic detritus in water. Trans. Brit. Mycol. Soc, 58: 281-290. 1973. Germination of the three spore forms of Mammaria echinobotryoides. Trans. Brit. Mycol. Soc, §0: 351-354. Parkinson, D. 1973. Technique for the study of s o i l fungi. In "Modern Methods in the Study of Microbial Ecology". T. R'osswall ed. Bull. Ecol. Res. Comm. (Stockholm), 17_: 29-36. and I. Balasooriya. 1967. Studies on fungi in a pinewood s o i l . I. Nature and distribution of fungi in the different s o i l horizons. Rev. Ecol. Biol. Sol., -4: 463-478. 1969. Studies on fungi in a pinewood s o i l . IV. Seasonal and spatial variations in the fungal population. Rev. Ecol. Biol. Sol., 6: 147-153. , T...R. G. Gray and S. T. Williams. 1971. Methods for studying the ecology of s o i l micro-organisms. IBP Handbook No. 19. Blackwell Scientific Publications, Oxford and Edinburgh. 116 pp. 169 Paterson, R. A. 1967. Benthic and planktonic phycomycetes from northern Michigan. Mycologia, 59_: 405-416. Petersen, R. H. 1962. Aquatic Hyphomycetes from North America. I. Aleuriosporae and key to the genera. Mycologia, J54;: 117-151. 1963a. Aquatic Hyphomycetes from North America. II. Aleuriosporae and Blastosporae. Mycologia, jj_5: 18-29. 1963b. Aquatic Hyphomycetes from North America. III. Phialosporae and miscellaneous species. Mycologia, _5_5: 570-581. Pi t t , J. I. 1966. Two new species of Chrysosporium. Trans. Brit. Mycol. Soc, 49: 467-470. Potter, L. F. and G. E. Baker. 1956. The microbiology of Flathead and Rogers Lakes, Montana. I. Preliminary survey of microbial populations. Ecology, 37: 351-355. 1961. The microbiology of Flathead and Rogers Lakes, Montana. II. Vertical distribution of the microbial populations and chemical analyses of their environments. Ecology, 42_: 338-348. Pugh, G. J. F. 1960. The fungal flora of t i d a l mud-flats. In "Ecology of Soil Fungi". An International Symposium. D. Parkinson and J. S. Waid ed. Liverpool University Press, pp. 202-208. 1962. Studies on fungi in coastal soils. II. Fungal ecology in a developing salt marsh. Trans. Brit. Mycol. Soc. , 45_: 560-566. ' 1964. An investigation of soil-borne cellulose-decomposing fungi in Greece. Annls. Inst. Phytopath. Benaki N.S., 7_: 19-27. 1966. Cellulose-decomposing fungi isolated from soils near Madras. J. Indian Bot. Soc, 45: 232-241. 1969. Some problems in the classification of s o i l fungi. In "The Soil Ecosystem". J. G. Sheals ed. Systematics Association Publication, j8: 119-130. and C. H. Dickinson. 1965. Studies on fungi in coastal soils. VI. Gliocladium roseum Bainier. Trans. Brit. Mycol. Soc, 48: 278-285. and J. L. Mulder. 1971. Mycoflora associated with Typha l a t i f o l i a . Trans. Brit. Mycol. Soc, 57_: 273-282. Ranzoni, F. V. 1953. The aquatic Hyphomycetes of California. Farlowia, 4_: 353-398. Rautela, G. S. and E. B. Cowling. 1966. Simple cultural test for relative c e l l u l o l y t i c activity of fungi. Appl. Microbiol., 14: 892-898. 1 7 0 Reese, E. T. and M. H. Dowing. 1951. Activity of the Aspergilli on cellulose, cellulose derivatives and wool. Mycologia, 43_: 16-28. and H. S. Levinson. 1952. A comparative study of the breakdown of cellulose by microorganisms. Physiol. Plant., 5_: 345-366. and M. Mandels. 1963. Enzymic hydrolysis of cellulose and i t s derivatives. In "Methods in Carbohydrate Chemistry". III. R. L. Whistler ed., Academic Press, New York. pp. 139-143. Ri f a i , M. A. 1969. A revision of the Genus Trichoderma. Mycol. paper No. 116, Commonwealth Mycological Institute, Kew, England. 56 pp. Robak, H. 1932. Investigation regarding fungi on Norwegian ground wood pulp and fungal infection at wood pulp mills. Saert. Nyt Mag. Naturv., 71: 185-330. Roberts, R. E. 1963. A study of the distribution of certain members of the Saprolegniales. Trans. Brit. Mycol. Soc, 4(3: 213-224. Rooney, H. M. and K. H. McKnight. 1972. Aquatic Phycomycetes of L i l y Lake, Utah Great Basin. Naturalist, 32: 181-189. Routein, J. B. 1957. Fungi isolated from soils. Mycologia, 49_: 188-196. Saksena, S. B. 1955. Ecological factors governing the distribution of micro s o i l fungi in forest soils of Saugar. J. Ind. Bot. Soc, 34: 262-298. Scales, F. M. 1915. Some filamentous fungi tested for cellulose destroying power. Botan. Gaz., 6>0: 149-153. Schol-Schwarz, M. B. 1959. The Genus Epicoccum Link. Trans. Brit. Mycol. Soc, 42: 149-173. 1970. Revision of the Genus Phialophora (Moniliales). Persoonia, 6^: 59-94. Servazzi, 0. 1953. Pestalotia o Pestalotiopsis? Nuovo G. Bot. I t a l . , 60: 942-947. Sewell, G. W. F. 1959a. Studies of fungi in a Calluna-heathland s o i l . I. Vertical distribution in s o i l and on root surfaces. Trans. Brit. Mycol. Soc, 42: 343-353. 1959b. Studies of fungi in a Calluna-heathland s o i l . II. By the complementary use of several isolation methods. Trans. Brit. Mycol. Soc, 42: 354-369. Simmons, E. G. 1967. Typification of Alternaria, Stemphylium and Ulocladium. Mycologia, 59: 67-92. 171 Siu, R. G. H. 1951. Microbial decomposition of cellulose. Reinhold Publ. Co., New York. 531 pp. Skinner, C. G. and E. M. Mellem. 1944. Further experiments to determine the organisms responsible for decomposition of cellulose in s o i l s . Ecology, 25: 360-365. Skinner, F. A., P. C. T. Jones and J. E. Mollison. 1952. A comparison of a direct- and plate-counting technique for the quantitative estimation of s o i l microorganisms. J. Gen. Microbiol. , j>_: 261-271. Smith, G. 1954. An introduction to industrial mycology. 4th ed. Longmans, Green & Co., Ltd., London. 390 pp. Sparrow, F. K. 1968. Ecology of freshwater fungi. In "The Fungi. III. The Fungal Population". G. C. Ainsworth and A. S. Sussman ed. Academic Press, New York. pp. 41-93. Steel, R. G. D. and J. H. Torrie. 1960. Principles and procedures of sta t i s t i c s , with special reference to the biological sciences. McGraw H i l l Book. Company, Inc., New York. 473 pp. Steyaert, R. L. 1949. Contribution a 1'etude monographique de Pestalotia de Not. et Monochaetia Sacc.. Bull. Jard. Bot. Etat. Bruxelles, 19: 285-354. Stolk, A. C. and G. L. Hennebert. 1968. New species of Thysanophora and Custingophora gen. nov. . Persoonia, 5^: 189-199. Subramanian, C. V. 1952. Fungi isolated and recorded from Indian soils. Jour. Madras Univ., 22B: 206-222. 1971. Hyphomycetes - An account of Indian species, except Cercosporae. Indian Council of Agricultural Research, New Delhi. 930 pp. Sugiyama, J. 1969. Studies on Himalayan yeasts and molds. II. Mammaria  echinobotryoides and i t s a l l i e s . Trans. Mycol. Soc. (Japan), 9: 117-124. , Y. Sugiyama, H. Iizuka and T. T o r i i . 1967. IV. Mycological studies of the Antarctic fungi. Part 2. Mycoflora of Lake Vanda, an ice-free lake. In "Report of the Japanese Summer Parties in Dry Valleys, Victoria Land, 1963 - 1965". The Antarctic Record, National Science Museum, Tokyo, Japan, 28: 2247-2256. Sukapure, R. S. and M. J. Thirumalachar. 1963. Studies on Cephalosporium species from India. I. Mycologia, 55_: 563-569. 1965. Studies on Cephalosporium sp.. from India... I l l Sydowia, 19: 171-175. 172 Sukapure, R. S. and M. J. Thirumalachar. 1966a. Conspectus of species of Cephalosporium with particular reference to India species. Mycologia, 58: 351-361. 1966b. Studies of Cephalosporium species from India. II. Bull. Torrey Bot. Club, 93: 305-311. Sutton, B. C. 1973. Hyphomycetes from Manitoba and Saskatchewan, Canada. Mycol. paper No. 132, Commonwealth Mycological Institute, Kew, England. 143 pp. Suzuki, S. 1960a. Seasonal variation in the amount of zoospores of aquatic Phycomycetes in Lake Shinseiko. Bot. Mag. Tokyo, 7_3: 483-486. 1960b. Microbiological studies on the lakes of Volcano Bandai. I. Ecological studies on aquatic Phycomycetes in the Goshikinuma Lake group. J. Ecol. (Japan), 10: 172-176. 1961a. The seasonal changes of aquatic fungi in lake bottom of Lake Nakanuma. Bot. Mag. Tokyo, _74_: 30-33. 1961b. Ecological studies on the genus Pythium (aquatic fungi) in Japanese lakes. J. Ecol. (Japan), 1_1: 91-93. and H. Nimura. 1960. Aquatic Hyphomycetes in the lakes of Mt. Hakkoda. Jour. Jap. Bot. , 35_: 265-268. Taha, S. M., A. H. El-Damaty, S. A. Z. Mahmoud and A. M. Abdel-Hafez. 1967. Seasonal variation of microbial flora, organic matter and nitrogen fractions in Egyptian s o i l . J. Microbiol. U.A.R., _2: .195-219. Tansey, M. R. 1971. Agar-diffusion assay of c e l l u l o l y t i c a b i l i t y of thermophilic fungi. Arch. Mikrobiol., 77: 1-11. Taylor, C. B. 1948. The bacteriology of lakes. Endeavour, ]_: 111-115. Taylor, J. J. 1970. Further c l a r i f i c a t i o n of Sporotrichum species. Mycologia, 62: 797-825. Thornton, R. ..H. 1956. Fungi occurring in mixed oakwood/and heath s o i l profiles. Trans. Brit. Mycol. Soc, 42_: 485-494. Thrower, L. B. 1954. The rhizosphere effect as shown by some Victorian heathland plants. Austr. J. Bot., 2_: 246-267. Timonin, M. I. 1935. The micro-organisms in profiles of certain virgin soils in Manitoba. Can. J. Res. C, 13_: 32-46. Tresner, H. D., M. P. Backus and J. T. Curtis. 1954. Soil microfungi in relation to the hardwood forest continuum in southern Wisconsin. Mycologia, _46: 314-333. 173 Tribe, H. T. 1957. Ecology of micro-organisms in soils as observed during their development upon buried cellulose film. In "Microbial Ecology". Seventh Symposium Soc. Gen. Microbial., Cambridge University Press, pp. 287-298. 1960a. Decomposition of buried cellulose film, with special reference to the ecology of certain s o i l fungi. In "The Ecology of Soil Fungi". An International Symposium. D. Parkinson and J. S. Waid ed. Liverpool University Press, pp. 246-256. 1960b. Aspects of decomposition of cellulose in Canadian soils. I. Observations with the microscope. Can. J. Microbiol., 6: 309-316. Tubaki, K. 1954. Studies on the Japanese Hyphomycetes. I. Coprophilous group. Nagaoa, _ i : 1-20. 1957. Studies on the Japanese Hyphomycetes. III. Aquatic group. Bull. Nat. Sci. Mus. Tokyo, 3_: 249-268. 1958. Studies on the Japanese Hyphomycetes. IV. Miscellaneous group. Bot. Mag. Tokyo, 71: 131-137. 1960. On the Japanese aquatic Hyphomycetes. Scum and foam group referring to the preliminary survey of the snow group. Nagaoa, _7: 15-29. 1965. Contribution towards the fungus flora of Australia and New Zealand. Ann. Rep. Inst. Fermentation, Osaka, 2_: 39-62. 1969. Descriptive catalogue of I.F.O. fungus collection. Ann. Rep. Inst. Fermentation, Osaka, _+_: 60-68. 1973. Some aspects of geographical distribution of leaf l i t t e r fungi in Japan. Shokubutsu Byogai Kenkyu, Kyoto, ^: 61-69. and I. Asano. 1965. Additional species of fungi isolated from the Antarctic material. Sci. Rep., 1956 - 1962, E, 2_7: 1-12. and T. Yokoyama. 1971. Successive fungal flora on sterilized leaves in the l i t t e r of forests. I. Research communication, Inst. Fermentation, Osaka, 5_: 24-42. 1973. Successive fungal flora on sterilized leaves in the l i t t e r of forests. III. Ann. Rep. Inst. Fermentation, Osaka, 6: 27-49. Umbreit, W. W. and E. McCoy. 1951. The occurrence of Actinomycetes of the Genus Micromonospora in inland lakes. In "A Symposium on Hydrobiology". The University of Wisconsin Press, Madison, pp. 106-114. 174 Varghese, G. 1972. Soil microflora of plantations and natural rain forest of West Malaysia. Mycopath. Mycol. Appl., j48: 43-61. Waid, J. S. 1960. The growth of fungi in s o i l . In "The Ecology of Soil Fungi". An International Symposium. D. Parkinson and J. S. Waid ed. Liverpool University Press, pp. 55-75. Waksman, S. A. 1916. Soil fungi and their a c t i v i t i e s . Soil Sci., 2: 103-155. 1917. Is there any fungous flora of the soil? Soil Sci., 3: 565-589. 1932. Principles of s o i l microbiology. 2nd ed. Williams and Wilkins Company, Baltimore, Maryland. 894 pp. 1940. The microbiology of cellulose decomposition and some economic problems involved. Bot. Rev., 6\ 637-665. 1941. Aquatic bacteria in relation to the cycle of organic matter in lakes. In "A Symposium on Hydrobiology". The University of Wisconsin Press, Madison, pp. 86-105. and C. E. Skinner. 1926. Microorganisms concerned in the decomposition of cellulose in the s o i l . J. Bact. , ]L2_: 57-84. and R. L. Starkey. 1924. Influence of organic matter upon the development of fungi, bacteria and actinomycetes in the s o i l . Soil Sci., 17: 373-378. Wali, M. K., G. K. Gruendling and D. W. Blinn. 1972. Observations on the nutrient composition of a freshwater lake ecosystem. Arch. Hydrobiol., 69: 452-464. Walseth, C. S. 1952. Occurrence of cellulases in enzyme preparations from microorganisms. Tappi, _3_5: 228-233. Wang, C. J. K. 1965. Fungi of pulp and paper in New York. Tech. Pubis. N. Y. St. Coll. For. No. 87. 115 pp. Warcup, J. H. 1950. Soil plate method for isolation of fungi from s o i l . Nature, 166: 117-118. 1951. The ecology of s o i l fungi. Trans. Brit. Mycol. Soc, 34: 376-400. 1955. On the origin of colonies of fungi developing on s o i l dilution plates. Trans. Brit. Mycol. Soc, 38: 298-301. 1957. Studies on the occurrence and activity of fungi in a wheat-field s o i l . Trans. Brit. Mycol. Soc, 40: 237-259. 1959. Studies on Basidiomycetes in s o i l . Trans. Brit. Mycol. Soc, 42: 45-52. 175 Warcup, J. H. 1960. Methods for isolation and estimation of activity of fungi in s o i l . In "The Ecology of Soil Fungi". An International Symposium. D. Parkinson and J. S. Waid.ed. Liverpool University Press, pp. 3-21. Webster, J. and N. Lomas. 1964. Does Trichoderma viride produce gliotoxin and viridin? Trans. Brit. Mycol. Soc., 47: 535-540. Went, J. C. 1959. Cellophane as a medium to study the cellulose decom-position in forest s o i l . Acta Botan. Neerl., 8^: 490-491. and F. Jong de 1966. Decomposition of cellulose in soils. Antonie van Leeuwenhoek, 32_: 39-56. Werkenthin, F. C. 1916. Fungous flora of Texas soils. Phytopath., 6: 241-253. White, W. L., R. T. Darby, G. M. Stechert and K. Sanderson. 1948. Assay of c e l l u l o l y t i c activity of molds isolated from fabrics and related items exposed in the tropics. Mycologia, 4_0: 34-84. and M. H. Downing. 1953. Humicola grisea, a soil-inhabiting, c e l l u l o l y t i c Hyphomycete. Mycologia, 45: 951-963. Williams, S. T. and D. Parkinson. 1964. Studies of fungi in a podzol. I. Nature and fluctuation of the fungus flora of the mineral horizons. .J. Soil Sci., 15: 331-341. Willoughby, L. G. 1961a. The ecology of some lower fungi at Esthwaite water. Trans. Brit. Mycol. Soc, 44: 305-332. 1961b. Chitinophyllic chytrids from lake muds. Trans. Brit. Mycol. Soc, 44: 586-592. 1962. The ecology of some lower fungi in the English Lake District. Trans. Brit. Mycol. Soc, 45: 121-136. 1965. Some observations on the location of sites of fungal activity at Blelham Tarn. Hydrobiologia, 2_5: 352-356. and V. G. Collins. 1966. A study of the distribution of fungal spores and bacteria in Blelham Tarn and i t s associated streams. Nova Hedwigia, 12: 150-171. Windisch, S. 1951. Zur Biologie und Systematik des Milchschimmels und einiger ahnlicher Formen. I. Beitrage Biologie Pflanzen, >28: 69-130. Witkamp, M. 1960. Seasonal fluctuations of the fungusflora in mull and mor of an oak forest. Publ. Inst. Biol. Field Res., Arnhem, Netherl. , _46: 1-52. 1963. Microbial populations of leaf l i t t e r in relation to environmental conditions and decomposition. Ecology, 44: 370-377. 176 Wolf, F. A. 1967. Fungus spores in East African Lake sediments. IV. Bull. Torrey Bot. Club, 94: 31-34. and S. C. Cavaliere. 1966. Fungus spores in East African Lake sediments. III. J. Elisha Mitchell Sci. Soc. , 82_: 149-154. Wood, T. M. 1969. The relationship between ce l l u l o l y t i c and pseudo-cel l u l o l y t i c microorganisms. Biochim. Biophys. Acta (Amst.), 192: 531-534. 177 APPENDICES APPENDIX I ORGANIC MATTER(%), PH AND TEMPERATURE OF MARION LAKE SEDIMENTS AND NUMBERS OF VIABLE PROPAGULES PER GRAM OF DRY SEDIMENT, JUNE, 1970 TO APRIL, 1971-JUNE, 1970 AUGUST, 1970 3 3 Station Section Organic Matter (%:)' Fungal Numbers(X10 ) Organic Matter (%) Fungal Numbers(X10 ) I 27.5 18.931 28.2 24.518 1 II 27.0 8.115 26.9 10.081 I 29.8 29.756 28.2 31.830 2 II 28.3 6.500 27.5 13.710 I 29.5 31.481 29.0 47.943 3 II 27.2 10.333 25.4 14.534 I - - 31.2 24.742 4 II - - 29.0 10.714 I 30.7 30.034 27.2 25.882 5 II 24.8 13.148 25.9 11.607 I 25.8 17.967 25.5 27.789 b II 24.1 6.277 24.1 11.538 t—1 CO APPENDIX I —Continued Station Section Organic Matter(%) p H Temperature Fungal Numbers(X103) OCTOBER, 1970 I 27.7 6.1 7.8 28.686 II 26.7 5.8 7.8 15.758 I 28.2 6.1 7.8 37.129 II 27.5 5.7 8.1 12.150 I 27.3 6.0 7.8 45.427 II 27.2 5.7 7.8 11.157 I 28.0 6.2 7.8 31.757 II 25.7 6.1 7.8 6.757. I 26.7 6.0 7.8 37.383 II 26.0 6.0 7.8 16.930 I 27.2 6.2 7.8 39.959 II 26.5 6.2 7.8 13.298 DECEMBER, 1970 I 26.5 6.0 4.0 48.795 II 26.3 6.1 3.9 11.690 I 28.0 6.0 4.0 43.275 II 26.8 6.1 3.9 15.211 I 30.2 5.8 3.8 63.509 II 25.7 5.8 3.6 15.324 I 30.5 5.9 4.5 31.507 II 30.0 5.9 4.0 12.838 I 30.7 6.4 4.0 -II 28.8 6.6 3.9 — I 28.3 5.8 4.0 61.732 II 25.8 6.2 3.8 12.963 APPENDIX I —Continued Station Section Organic Matter(%) P H Temperature Fungal Numbers(XlOd) FEBRUARY, 1971 I 28.5 6.0 2.0 48.766 II 28.1 5.8 2.0 16.674 I 28.5 5.4 2.0 43.880 II 27.3 5.5 2.0 22.041 I 28.5 5.4 2.0 54.065 II 26.2 5.6 2.0 9.801 I 27.6 5.7 2.0 44.228 II 26.8 5.8 2.0 11.411 I 27.1 5.9 2.0 54.024 II 26.5 5.9 2.0 9.672 I 26.0 6.2 2.4 42.185 II 25.3 6.4 2.8 14.759 APRIL, 1971 I 28.0 6.3 7.0 40.236 II 27.6 - 6.5 9.532 I 28.6 6.4 6.0 34.593 II 27.1 - 5.8 18.600 I 30.8 5.7 5.3 40.065' II 26.8 6.0 5.0 14.957 I 31.2 6.1 6.0 31.410 II 28.6 7.2 6.0 8.629 I 31.1 — 5.8 32.402 II 26.8 - 5.5 12.507 I 28.8 — 6.0 37.662 II 26.0 6.8 6.0 5.487 181 APPENDIX II SPECIES NAME AND NUMBER SPECIES NUMBER SPECIES 1 (?)Acrogenospora state of Farlowiella carmichaeliana (Berk.) Sacc. 2 Alternaria alternata (Fr.) Keissler 3 Arthrinium sacchari (Speg.) E l l i s 4 Aspergillus spp. 5 Aureobasidium bolleyi (Sprague) von Arx 6 Aureobasidium pullulans (de Bary) Arnaud 7 Beauveria bassiana (Bals.-Criv.) V u i l l . 8 Botrytis cinerea Pers. ex Fr. 9 Candida sp. 10 Cephalosporium acremonium Corda 11 Cephalosporium incarnatum Sukap. & Thirum. 12 Cephalosporium incarnatum var. macrosporum Sukap. & Thirum. 13 Cephalosporium incoloratum Sukap. & Thirum. 14 Cephalosporium khandalense Thirum. & Sukap. 15 Cephalosporium spp. 16 Chloridium chlamydosporis (van Beyma) Hughes 17 Chrysosporium pannorum (Link) Hughes 18 Cladosporium cladosporioides (Fresen.) de Vries 19 Cladosporium herbarum (Pers.) Link ex Gray 20 Cladosporium macrocarpum Preuss 21 Cladosporium musae Mason 22 Cordana pauciseptata Preuss 23 Cylindrocarpon destructans (Zins.) Scholten 24 Cylindrocarpon didymum (Hartig) Wollen. 25 Cylindrocarpon (?)lucidum Booth 27 Epicoccum purpurascens Ehrenb. ex Schlecht. 28 Geniculosporium serpens Chesters & Greenhalgh 29 Geotrichum candidum Link ex Persoon 31 Gliocladium catenulatum Gilman & Abbott 34 Gliocladium roseum Bainier 35 Gliocladium virens M i l l . , Gidd. & Fost. 36 Gliocladium spp. ' 37 Gliomastix murorum (Corda) Hughes 38 Gliomastix spp. 40 (?)Humicola sp. 41 Mammaria echinobotryoides Ces. 42 Metarrhizium anisopliae (Metsch.) Sorokin 43 Myrothecium sp. 45 Oedocephalum spp. 47 Oidiodendron griseum Robak 48 Oidiodendron periconioides Morrall 49 Oidiodendron tenuissimum (Peck) Hughes 50 Paecilomyces carneus (Duchg et Heim) Brown & Smith 51 Paecilomyces elegans (Corda) Mason & Hughes 52 Paecilomyces griseovirides Onions & Barron 53 Paecilomyces roseolus Smith APPENDIX II —Continued 182 SPECIES NUMBER SPECIES 54 Paecilomyces terricola (Mill., Gidd. & Fost.) Onions & Barron 55 Paecilomyces spp. 60 Penicillium spp. 61 Periconiella sp. 62 Pestalotia monochaetioides Doyer 63 Pestalotia truncata Lev. 64 Pestalotia versicolor Speg. 65 Phialophora (?)alba Beyma 66 Phialophora fastigiata (Lagerb. & Melin) Conant 67 Phialophora sp. (C163, C295)* 68 Phialophora spp. 70 Septonema secedens Corda 71 Sporobolomyces sp. 72 Sporothrix sp. 73 Thysanophora penicillioides (Roum.) Kendrik 74 Torulomyces lagena Delitsch 75 Trichocladium opacum (Corda) Hughes 76 Trichoderma hamatum (Bon.) Bain. aggr. sensu R i f a i 77 Trichoderma hamatum (Bon.) Bain. aggr. sensu R i f a i (NS) 78 Trichoderma koningii Oud. aggr. sensu Ri f a i 79 Trichoderma polysporum Link ex Pers. aggr. sensu Ri f a i 80 Trichoderma saturnisporum Hammill 81 Trichoderma viride Pers. ex Gray aggr. sensu R i f a i 82 Trichoderma spp. 84 Umbelopsis versiformis Amos & Barnett 85 Ver t i c i c l a d i e l l a procera Kendrick 86 Verticillium state of Nectria inventa Pethybr. 87 Verticillium (?)terrestre (Link) Lindau 88 Xylocladium state of Hypoxylon punctulatum (Berk. & Rav.) Cooke 89 Hyaline Mycelia S t e r i l i a 90 Dark Mycelia S t e r i l i a 93 Unidentified—12 94 Mortierella isabellina Oud. 95 Mortierella vinacea Dixon & Stewart 96 Mucor spp. 97 Anixiopsis sp. 98 Coniothyrium sp. 100 Emericellopsis terricola van Beyma 101 Pseudoeurotium zonatum van Beyma 102 Pyrenochaeta sp. 103 Unidentified Author s stock culture numbers. Wl-KKOIS 111 » i U * I U L DISI»IBl.T !0;t. 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