PARASITIC FUNGI AND MOULDS. 



13 



In this case, the spores or seeds are developed in the 

 cells of the mycelium itself. 



This latter mode of reproduction also occurs in the 

 higher fungi, which therefore possess two modes of 

 reproduction and two kinds of spores : exogenous 

 spores, which are externally developed, as we see on 

 the hymenium (Fig. 2); and endogenous or internal 

 spores, which are developed in 

 the mycelium (Fig. 4). These 

 spores not only differ in the 

 site of their origin, but also in 

 their form, size, structure, and 

 in the end they fulfil in the 

 reproduction of the fungus. 

 There are in many cases several 

 forms of exogenous spores. 



Classification of Fungi. 

 The nature of the spores, and 

 the very varied mode of reproduction, have led to 

 the classification of fungi in a certain number of 

 groups, of which we need only cite the most im- 

 portant, and those which chiefly concern our present 

 point of view. Such are 



1. The Hymenomycetes. 



2. The Basidiomycetes. 



3. The Ascomycetes. 



4. The Oomycetes. 



Each of these groups is subdivided into several 

 sections or families. Ferments and Schizomycetes, or 



Fig. 4. Endogenous spores from 

 the mycelium of Agaricus 

 (much magnified). 



