146 PHYCOMTCETEAE 



Conidia germinating by the formation of a single large naked nonflagellate 

 plasmatic mass which encysts and then germinates by a single germ tube. 



Plasmopora 

 Conidia germinating by the production of biflagellate zoospores. 



RJujsotheca 

 Conidiophores slender, more or less dichotomously branched, mostly at acute 

 angles. Conidia usually germinating by single germ tube, or by zoospores. 

 Tips of branches enlarged into disks with sterigmata at the margin. Parasitic 



upon Cichoriaceae. Zoospores rare. Bremia 



Tips of branches swollen, but not disk-like. Parasitic on Viola. Zoospores 



rare or none produced. Bremiella 



Tips of branches acute, conidia germinating by a germ tube. 



Peronospora 

 TiDS of branches acute, conidia germinating by zoospores. 



Pseudoperonospora 



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