8o DISEASES OF CULTIVATED PLANTS 9 



finally killed by the mycelium of the fungus, which converts 

 its body into a mummified mass of spawn, which at a later 

 stage produces a club-shaped spore-bearing structure, the 



FIG. 13. Species of Cordyceps, parasitic 

 on caterpillars which they have killed. 

 Reduced. 



spores from which in turn infect other caterpillars. Certain 

 kinds of fungi confine their attentions to particular kinds of 

 insects, and of late years considerable progress has been 



