PHYCOMYCETES. 



Algae fungi. The organs of fructification are so similar to 

 some of the algae tribes that it was considered a proper name 

 for this group. They include some of the Mucidines of Fries. 

 Many species are parasitic on cultivated plants, doing consid- 

 erable damage to crops. 



Spores like algae spores are produced asexually as conidia 

 and zoospores and sexually as zygospores or oospores. 



The principal systematic literature is Berlese et De Toni 

 Phycomyceteae in Seccardo, Sylloge Fungorum. 



The genera which I am able to describe, and indigenous in 

 our Valley, are : 



Cystopus. 



Peronospora. 



Phytophthora. 



MUCOR. 



Genus I. CYSTOPUS. DeBary. 



Receptacle consisting of thick, branched threads ; conidia 

 concatinate, at length separating, oospores deeply seated on 

 the mycelium. 



C. candidus. Ivcv. Crucifera White Rust. 



Conidia equal, globose. Oospores subglobose ; epispore 



yellowish brown with regular obtuse warts. 



In this genus there are two kinds of reproductive organs, those pro- 

 duced on the surface of the plant, bursting through the skin in white 

 pustules, which DeBary called the conidia, and are generated in chains, 



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