HYPHOMYCETES 



405 



in its interior and destroys all structure. The conidio- 

 phores of the Isaria form then appear on the surface of the 



FIG. 137. Cercospora circnmscissa, a fungus whose conidial 

 fruit consists of a single conidium produced at the tip of a short, 

 unbranched conidiophore. i, peach leaf showing blackened 

 spots caused by the fungus. The small circular patches of leaf 

 tissue killed by the fungus soon dry up and fall, leaving a number 

 of holes in the leaf, hence the popular name of ' shot-hole 

 fungus." 2, a cluster of conidiophores bearing septate conidia. 

 Fig. i, nat. size ; fig. 2, mag. 



body under the form of erect, feathery tufts, usually of a 

 yellowish colour. Some time afterwards the ascigerous 

 condition of the fungus appears on the surface, under the 



