284 CLASSIFICATION OF SACCHAllOMYCETACE^. 



one or more fat globules. The inoculation streaks on wort gelatin 

 form lustrous white colonies; the gelatin is not liquefied. The 

 spores are globular and measure 2-4 /x, and occur singly or in pairs. 

 The species forms oxalic acid in solutions of dextrose, galactose, 

 saccharose, lactose, maltose, dulcitol, glycerol, and mannitol. It 

 was discovered in cotton-seed meal. Owing to the brief description 

 (film formation ?), the position of the species is doubtful. 



Closely allied to the genus Saccharomyces are the two following 

 genera, Hansenia and Torulaspora. 



In the genus Hansenia, P. LINDNER (XXXIT.), many of the 

 cells are lemon-shaped, in other respects they exhibit the same 

 characteristics (including sporulation) as the genus Saccharomyces. 

 Lindner proposed to apply this generic name to "the Apiculatus 

 yeasts " without giving any further indications, on the basis that all 

 the *' Apiculatus yeasts " produce spores. However, since the 

 species named Sacch, apiculatus by Reess is asporogenic, it cannot 

 be classed with this genus. For the present, only that species which 

 is morphologically analogous to Sacch. apiculatus, but differs there- 

 from in being sporogenic, can be included in the genus Hansenia. 

 A few species belonging to this genus have been discovered by 

 Beijerinck, Lindner and Rohling, but have not yet been more 

 fully described. 



In the genus Torulaspora, P. LINDNER (XXII. ), the cells are 

 small and globular, with a single large fat globule in each, and 

 resemble the cells of Torula. Lindner has not yet enumerated 

 the characteristics of this genus either, except to cite as typical 

 the species Torulaspora Delbrucki, LINDNER (XXXII.), formerly 

 described and illustrated by him (XXXI.) under the name Sacch. 

 Delbrucki. This species exhibits 1-2 spores in a cell, ferments 

 dextrose and Isevulose, and was discovered in English ale. 



Although the cell form is the only characteristic as yet speci- 

 fied in connection with the two foregoing genera, they have been 

 included here because of the probability of a sufficient characteri- 

 sation being established later on. For the present they cannot 

 be differentiated from the genus Saccharomyces, the cell form 

 alone being insufficient to serve as a generic characteristic. 



279. The Genera Zygfosaeeharomyees, Saeeharo- 

 myeodes and Saccharomycopsis. 



The genus Zygosaccharomyces, BARKER (I.), coincides in general 

 with the genus Saccharomyces, but differs therefrom in respect of 

 the phenomenon of cell fusion, which precedes sporulation. 



Zygosaccharomyces Barker i, SACCARDO and SYDOW (I.) was first 

 described and drawn by BARKER (I.), but without being invested 

 by him with a systematic specific name. The cells are oval. 

 The limits of budding temperature on wort agar-agar are 

 37-38 C. and io-i3 C. This species develops merely a yeast 



