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YEASTS AND YEAST-LIKE FUNGI 



GENERA OF ENDOMYCETACEAE 



(Adapted from Stelling-Dekker) 



Class ASCOMYCETES Order ENDOMYCETALES 



Subfamily A. 



Subfamily B. 



Subfamily C. 



EREMASCOIDEAE. Growth form, only mycelium. Asco- 

 spores formed by isogamous conjugation, hat-shaped, 4 to 8 

 per ascus. Entirely oxidative. But one genus, EREMASCUS, 

 description as for the subfamily. 



ENDOMYCOIDEAE. Growth form, either myceUum and 

 arthrospores or arthrospores alone. Spores formed by isoga- 

 mous or heterogamous conjugation, or parthenogenetic. Oxi- 

 dative or fermentive. 



Genus I. ENDOMYCES. Both mycelium and arthrospores. Spores 

 by heterogamous conjugation or parthenogenetic, round to 

 hat-shaped, 4 per ascus. Oxidative or fermentive. 



Genus II. SCHIZOSACCHAROMYCES. No mycelium, only arthro- 

 spores. Spores by isogamous conjugation, 4 to 8 per ascus. 

 Dominant ly fermentive. 

 SACCHAROMYCOIDEAE. Either mycelium with blastospores, 

 or only budding yeast cells, the latter often with pseudo- 

 mycelium. Multiplication by fission, by multipolar budding, 

 or by bipolar budding. Spores by heterogamous or isogamous 

 conjugation or parthenogenesis. All transitions from purely 

 oxidative to purely fermentive forms. 

 Tribe a. ENDOMYCOPSEAE. Mycelium with blastospores, occasionally 

 arthrospores. Multiplication by fission or multipolar budding. 

 Spores parthenogenetic or by isogamous conjugation; round, 

 oval, sickle-shaped, or hat-shaped, 1 to 4 per ascus. Domi- 

 nantly oxidative. But one genus, ENDOMYCOPSIS, descrip- 

 tion as for the tribe. 

 Tribe b. SACCHAROMYCETEAE. Mycelium rare or lacking, budding 

 yeast cells the usual growth forms. Multipolar budding. 

 Spores parthenogenetic or by isogamous or by heterogamous 

 conjugation. 



Genus I. SACCHAROMYCES. Round, oval, or cylindrical cells. 

 Spores round, kidney-shaped, or hat-shaped, smooth, 1 to 4 

 per ascus. More or less strongly fermentive in all cases, in 

 addition to oxidative. 

 Subgenus SACCHAROMYCES sensu stricto. Spores partheno- 

 genetic. 

 Subgenus ZYGOSACCHAROMYCES. Spores by isogamous or 

 heterogamous conjugation. 



Genus II. TORULASPORA. Round cells. Spores formed after un- 

 successful attempts to conjugate. Spores round, smooth, 1 to 

 3 per ascus. Dominantly fermentive. 



Genus III. PICHIA. Cells oval to long cylindrical. Pseudomycelium 

 formed. Spores parthenogenetic, or by isogamous or heteroga- 

 mous conjugation, angular or hemispherical, 1 to 4 per ascus. 

 Dominantly oxidative, weakly fermentive. Nitrates not re- 

 duced. 



