468 INDEX 



X-Rays, effect of, 123 



Yeast, 7, 13, 14, 43 

 bottom,. 48 

 cellulose, 43 

 classification, 47 

 commercial preparation of, 190 

 false, 47 

 pathogenic, 393 

 relationships, 47 



Yeast, structure, 43 



spores, 45 



top, 48 



true, 47 



vegetative multiplication, 44 

 Yellow fever, 399 

 Yersin, 350 



Zygospore, 53 

 Zymases, 161, 166, 183 



U) 



