CHAPTEE III 



CLASSIFICATION OF FUNGI 



IN the classification of the fungi in a work of this kind, 

 only the most important groups can be considered. In 

 this part of the work will be given a discussion of the 

 fungi and other organisms that cause disease, and in the 

 latter chapters will be given discussions of the diseases 

 of the various crops. 



The Fungi are divided into three large groups as 

 follows : 



1. The PHYCOMYCETES (Lower or Algal Fungi). The 

 members of this group are very much like the algae in 

 both structure and reproduction, but since they do not 

 contain chlorophyll, their habits are necessarily very 

 different. They range in structure from species con- 

 sisting of a single cell composed of an undifferentiated 

 mass of protoplasm to species consisting of a well 

 developed mycelium. The reproduction is usually by 

 the non-sexual method, and some species are parasitic 

 while others are saprophytic. 



2. The ASCOMYCETES (Sacspore Fungi). This group 

 includes the great majority of fungi that cause diseases, 

 and its members are usually much more complicated in 

 structure than the preceding and bear very little resem- 

 blance to the algae. They may range from species in which 

 the individual consists of a single, small, spherical cell 

 floating in a liquid, to species in which the individuals 

 are large and fleshy. However, the great majority are 

 inconspicuous. Some of the large fleshy forms are 

 edible. 



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