Chapter IX — 131 — Yeasts and Molds 



oyster-growing areas revealed the presence of the pink yeast. It could 

 also be recovered from healthy oysters. 



There are frequent references in the literature to the occurrence of 

 yeasts in lakes. Many of the numerous species of true yeasts, torulae, and 

 yeast-Hke organisms found in the soil have been reported in lakes. Gen- 

 erally they are most abundant near shore or associated with higher aquatic 

 plants such as Sagitlaria, Myriophyllum, Naias, Zostera, Lemna, Elodea, 

 Vallisncria, Potarnogeton, Chara, Cladophora, etc. 



Marine molds : — Disregarding those obviously originating from air 

 contamination, Fischer (1894a) found molds in the sea far less frequently 

 than either bacteria or yeasts. With very few exceptions, he found nu- 

 merous molds in sea water only fairly close to land. The molds which 

 Fischer observed were common species of terrestrial fungi, primarily 

 Penicillium and Aspergillus. Waksman (1934) also observed that com- 

 mon dust and wind-borne species of Penicillium and Aspergillus occupy a 

 prominent place among the fungi reported in marine materials. 



In marine muds from the Woods Hole region. Sparrow (1937) found 

 species of Penicillium, Aspergillus, Rhizopus, Alternaria, Cephalosporium, 

 Tric/ioderma, Chaetomium, and Cladosporium associated with decaying 

 phytoplankton. He doubts, however, that these are true marine fungi. 

 Though definitely able to live in the sea, most of them were well-known 

 terrestrial species. 



Owing to their small size and the difficulty of observing them under 

 anything like natural conditions, the search for fungi associated with 

 marine algae has been disappointing. The additions made by most my- 

 cologists have been few and accidental. Sparrow (1934) remarked re- 

 garding marine Phy corny cetes that "one is at once confronted with a very 

 real problem in endeavoring, first, to find sporangia which have not al- 

 ready discharged their zoospores in the interval between collection and 

 examination, and, secondly, to produce conditions in the laboratory 

 favorable for the development and discharge of these sporangia. This, 

 together with the very small size of zoospores produced by these fungi, 

 has greatly retarded our knowledge." 



Petersen (1905) made a systematic search for fungi along the coast 

 of Denmark where he found several species of chytridiaceous Phycomy- 

 cetes growing either parasitically or saprophytically on marine algae. He 

 described the fungi now known as Petersenia lobala, P. pollagaster, Sirol- 

 pidium bryopsidis, Olpidium laguncula, Ectrogella perforans, Rhizophydium 

 discinctum, Pleotrachelus inhabilis, PI. minutus, PI. paradoxus, PI. rosen- 

 vingii, and Pontisjna lagenidioides . 



Sutherland (1915a) described five new species of Fungi Imperfecti, 

 Mycosphaerella pelvetiae, Stigmalea pelvetiae, Pharcidia pelvetiae, Pleospora 

 pelvetiae, and Macrosporium pelvetiae, which were found associated with 

 species of the rockweed Pelvetia along the coast of Britain. He (1915&) 

 also described Orcadia pelvetiana, Didymosphaeria pelvetiana, Didymos- 

 phaeriafiicicola, and Hypoderma laminariae. These Pyrenomycetes were 

 parasitic on Pelvetia, Fucus, and Laminaria respectively. 



From the green alga, Codium mucronatum, growing in the Puget 

 Sound region, Zeller (1918) isolated and described Chytridium codicola, 

 Rhizophydium codicola, and Stemphylium codii. 



Twelve species of marine Phycomycetes were collected by Sparrow 

 (1934) in the Kattegat near Frederikshavn, Jutland, including Pythium 



