382 



MICRO-ORGANISMS AND FERMENTATION. 



species by-thelfusion of two cells which are often sister cells, 

 .but asc us-formation may take place without previous fusion. 

 In plate and streak-cultures the growths, both on and 



-Saccharomyces mellacei. Young culture in beer-wort ; a, cells after eight days' 

 cultivation (drawn by Holm from nature). 



Fig. 87. Saccharomyces mellacei. Growth from the yeast ring in beer-wort (drawn 

 by Holm from nature). 



below the surface, have a sharp-cut edge ; the cell-forms are 

 similar to those in liquids ; cells shaped like the conidia of 

 Oidium lactis frequently occur. 



