YEASTS E AND F 225 



In old cultures on wort, this yeast forms a viscous scum more 

 or less developed. Often the formation of a very thin ring may be 

 noticed. 



After a month's sojourn at room temperature, giant colonies on 

 wort gelatin appear well developed with a grayish color. They re- 

 semble wax and possess a glistening appearance. The edge is slightly 

 notched. 



This species ferments dextrose, levulose, and raffinose, sometimes 

 inuline, but has no action on lactose or maltose. It inverts sucrose 

 more or less actively. 



Genus VI. Torulaspora. Lindner 



Cells round, spherical, small, provided with a large globule of fat 

 and resembling Torula. These characteristics, as remarked by Klocker; 

 are insufficient to characterize the genus. However the trace of 

 copulation which is present in the Torulaspora, recently pointed out 

 by L. Rose, added to the characters described by Lindner, seem suf- 

 ficient to differentiate this genus. 



TORULASPORA DELBRUCKII. Lindner 



This species was discovered by Lindner 1 in English beer. (Fig. 94.) 

 The ascospores are to the number of 3 to 5 in each asc. According to 

 Rose, the ascs possess spurs analogous to 



those which have been observed in the C^tiT^ ^ O/O> 



Schwanniomyces which may be regarded Ow^/rv^feA (^T 

 as traces of copulation. This yeast is f^f^ r ^- * ^/ 

 able to ferment dextrose, levulose, d-man- 

 nose and d-galactose. 



YEASTS E AND F. Rose 



$\ 



This species was isolated from the 

 mucous secretions of oak trees by Rose 2 

 in 1910. Both present the characteristics 

 of the genus Torulaspora and seem to be identical. They possess 

 round cells (3.5 to 4.5 ju in diameter) and grow on beer wort quite 

 well, but do not produce fermentation. 



The ascs develop at the end of three days on Gorodkowa's 

 gelatin and plaster blocks at 25 C. They show attempts at copula- 



1 Lindner, P. Mikroskopische Betriebskontrolle in den Garungswerben. 

 Paul Parey, edit. Berlin, 6th edition, 1909. 



2 Rose, L. Beitrage zur Kenntniss der Organismen in Eichenschleimfluss. 

 Inaugural dissertation, University of Berlin, June 25, 1910. 



