44 DISEASES OF CROP PLANTS 



Class II. Ascomycetes. 



(a) Hemi- and Protoasci (yeasts, Exoascus, etc.) 



(b) Plectasci (common blue, green and yellow moulds). 



(c) Discomycetes (Sclerotinia and other cup fungi). 



(d) Helvellineae. 



(e) Pyrenomycetes. 



1. Perisporiales (powdery mildews and sooty moulds). 



2. Hypocreales (Nectria, etc.) 



3. Dothideales. 



4. Sphaeriales (most forms with black perfect fruiting 

 bodies). 



Class III. Basidiomycetes. 



{a) Hemi- and Protobasidii. 



1. Ustilaginales (smuts). 



2. Uredinales (rusts). 



{b) Hymenomycetes (Marasmius, Corticium, gill and 



pore fungi, 

 (c) Gasteromycetes (puff-balls, etc.) 



Class IV. Fungi Imperjecti. 



1. Sphaeropsidales (Diplodia, Phoma, etc.) 



2. Melanconiales (anthracnose fungi, etc.) 



3. Moniliales or Hyphomycetes (Fusarium, etc.) 



