PLATE 2. 



Erysipheae. 



rneiniila Salicis, (D C.). 







Fii\ 1. Xatural size on leaf of Salix flavescens, var. Scouleriana, 

 from Montana. 



2. Part of a leaf with perithecia magnified. 



3. Aperithecium highly magnified. 



4. An ascus. 



5. Three sporidia. 



6. A conidia-bearing hypha. 



7. Five conidia. 



3. Initial hypliae forming a perithccium. 



