FUNGI : SAPROLEGNIA. 



133 



Fig. 199 



Fertilization in saprolegnia, tube of antheridium carrying in the nucleus of the sperm cell 

 io the egg. In the right-hand figure a smaller sperm nucleus is about to fuse with the 

 s of the 



nucleus 



egg. (After Humphrey and Trow.) 



Fig. 200. 

 Branching hypha of Peronospora alsinearum. 





Fig. 201. 



Branched hypha of downy mildew 

 of grape showing peculiar branching 

 (Plasmopara viticola). 



