242 



FAMILY OF SACCHAROMYCETACEAE 



Temperatures for Ascospore Formation 

 At 32.5 no development of ascospores. 



30.5-31.5 appearance of first rudiments in about 36 hours. 

 29.5 " " '" " 23 " 



25 " " " 21 " 



18 " " " " 33 



15 

 10.5 



4 no development of ascospores. 



41 days 

 11 " 



The ascs are ordinarily ellipsoidal and small. They enclose from 

 one to four ascospores which measure 2 to 5 /* (Fig. 113). They 

 germinate after having copulated two by two (Marchaud) in about 

 half of the cases. 



Temperature for Formation of Scum 

 At 38 no formation of scum. 

 33-34 at the end of 8-12 days fully developed. 

 26-28 " " " " 9-16 " " 

 20-22 " " " " 10-17 " " " 



13-15 " " " " 15-30 " 



6-7 " " " " 2-3 months 



5 no formation of scum. 



Microscopic appearance of the cells in the 

 scum is as follows: At 20-34 C. and at 6-7 C., 

 the scum includes cells which are small among 

 which the sausage-shaped cells are abundant. At 

 13-15 C. in old scums, one may see branching 

 Fig. 114. S. ellip- colonies with sausage-shaped cells, either shorter 

 ^tor^fcum 1 !? elongated. (Fig. 114.) In beer wort to which has 

 13-15 C. (after Han- been added 5| per cent of gelatin, on streaks 

 at 25 C., one may very closely separate the cells 

 of the preceding species. (S. cerevisiae, Pastorianus, intermedius and 

 validus) by a peculiar structure in the form of a network which is not 

 able to escape the naked eye. This yeast ferments saccharose, dextrose 

 and maltose. 



YEASTS RELATED TO S. Ellipsoideus 



Numerous yeasts are used in the making of wine which are related 

 to S. ellipsoideus. They have been described by Aderhold, Hotter, 



