ASEXUAL REPRODUCTION 99 



homologous with those where fertilisation is evident, but 

 in which the sexual organs are now rudimentary, will be 

 included under this heading, and left out of discussion in 

 the present chapter. There still remain a great variety of 

 reproductive bodies of undoubted asexual origin, respec- 

 tively called spores, conidia, etc. All these and others 

 are produced on specialised portions of the mycelium, 

 whereas a second batch of reproductive bodies are purely 

 vegetative in origin, as sclerotia, gemmae, etc. 



We will commence with those forms borne on specialised 

 portions of the fungus, and at the outset are confronted 

 with the difficulty of clearly defining the various terms used 

 to distinguish the different kinds, owing to the vague 

 manner in which they have been designated by different 

 authors. 



Basidiospores are characteristic of the Basidiomycetes 

 and the Protobasidiomycetes, and in these instances are 

 exogenous in origin, being borne on basidia. In systematic 

 works basidiospores are almost invariably called spores. 

 The reproductive bodies produced in the asexual sporangia 

 of the Mucorineae are called spores. 



Typical conidia are the asexual summer form of fruit, 

 borne on conidiophores in the Ascomycetes. As a rule, 

 the production of conidia commences early in the season, 

 and lasts through the summer. These bodies are produced 

 in immense numbers and in quick succession, are readily 

 dispersed by wind, insects, birds, mammals, and other 

 agents, and are capable of germination the moment they 

 are mature. Their special function is that of extending 

 the geographical area of the species producing them. In 

 the case of parasitic species the outbreak of an epidemic 

 is caused by the rapid production and dispersion of the 



