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to this fungus being the cause of fever or any similar disease there is 

 not the slightest grounds for such a belief. There may be some con- 

 nection, however, between the parasite and certain fevers, as the same 

 climatic conditions that favor one may also influence the other. There 

 are in the United States about seventy-five species of the so called 

 powdery mildews, which occur on widely different host plants. I send 

 with this a few specimens. 



