New York Agricultural Experiment Station. 375 



s. The sporophore proper. 

 sp. Immature spore. 

 p. Mass of protoplasm. 

 Figs 2, 2' and 2'^ Mature spores of the ordinary normal form. 

 (Original.) 



Fig. 3. Shows how the sporophores come ont through the 

 stomata. (Original.) 



s. Portion of a mature sporophore. 

 If. A young sporophore. 

 St. The stoma. 



7)1. A fragment of the mycelium. 

 Fig. 4. A cluster of sporophores taken in dry weather from a 

 cucumber leaf grown out of doors. (Original.) 



s, s\ .s". s'''. Four stunted sporophores of the normal 



branched form. 

 u. An abnormal unbranched sporophore bearing a mon- 

 strous spore. 

 t, t\ t". Transition forms between s and w. 

 Fig. 5. A cluster of very short-stalked spores from a cucumber 

 leaf. (Original.) 



Fig. 6. A short-stalked spore from a muskmelcn leaf. (Orig- 

 inal.) 



Fig. 7. Four cells of a cucumber leaf with the mycelial threads 

 of the fungus running between them and sending into them the 

 haustoria (/^, h', h"). (Copied after Humphrey in 8th Ann. R'^pt. 

 Mass. Exp. Sta.) 



Fig. 8. A rare form of short-stalked spore from a cucumber 

 leaf. (Original.) 



Fig. 9. A monstrous pear-shaped spore which was found at- 

 tached to a well-developed sporophore after the manner of the 

 ordinary spores. Two other spores of this character have been 

 observed. (Original.) 



Note. — All figures on this plate are equally magnified, viz.: 

 -105 diameters; and with the exception of Fig. 7 all were drawn 

 v.ith the aid of an Abb6 camera lucida in the same manner as the 

 figures on Plate XI. 



