280 



FAMILY OF SACCHAROMYCETACEAE 



from a copulation. These authors show ascs formed from two cells 

 united by a canal. Sometimes only one will produce ascospores and 

 sometimes both. (Fig. 132.) Guilliermond l has shown that these 

 illustrations simply represent budding. In fact, the cells destined to 

 sporulate are able to continue budding at the moment of sporula- 

 tion and the ascospores often form before the separation of the cell 



which is formed in the bud- 

 ding process. Sometimes 

 the bud will form on the 

 lateral surface of the cell, 

 then will elongate parallel 

 with the mother cell which 

 results in forms resembling 

 the Zygosaccharomyces. 



The giant colonies on 

 maltose gelatin are circular 

 and have a chalky white 

 appearance. On gelatin 

 streaks, the culture is also 

 Vegetative Cells whitish and the edge finely 



Fig. 132. Pichia farinosa. 



and Ascs in Scum on Beer Wort (after Lind- 

 ner). 



indented. Liquefaction of 

 the gelatin is quite rapidly 

 accomplished. The giant colonies are chalky white with a folded 

 surface and slowly liquefy the gelatin. This yeast feebly ferments dex- 

 trose and levulose but has no action on other sugars (maltose, d-galac- 

 tose, saccharose, melibiose, raffinose, a-methylglucosides). In beer 

 wort, the amount of alcohol produced is very small. In 11 days, 0.9 

 per cent of alcohol and ethyl ether is formed. According to Siefert, 

 Pichia farinosa produces in alcoholic must acetic acid. 



PICHIA SUAVEBLEUS. Klocker 



Found in soil in Denmark, this species forms 

 on must at the end of 24 hours at 25 C. a gray 

 scum which adheres to the walls of the flask, and 

 a white thick ring. On beer wort the scum is 

 thick and compact with a yellowish color. The 

 cells in the scum are spherical or oval (5 to 8/z 

 long). The temperature limits for the formation 

 of scum are 34-36 C. and 10-4 C. The ascospores 

 are spherical sometimes flattened on one side with 



1 Guilliermond, A. Quelques remarques sur la sexualite des levures. Annals, 

 rnycologici, 8, 1910. 







Fig. 132-bis. Pichia 

 suavebleus. Cells from 

 a Young Scum on 

 Beer Wort (after 

 Klocker). 



