General Features 



23 



mosses and some species of Lam pros pora show the same tendency. 

 Others grow on decaying wood, often showing a preference for 

 certain kinds of wood, while still others occur on burnt soil or on 

 dung, being designated as pyrophilous and coprophilous forms 

 respectively. Since the latter forms are of more than usual 

 interest they will be treated more in detail. 



14. Pyrophilous Cup-fungi 



There are quite a number of operculate cup-fungi which 

 occur in nature only on burnt places, especially where piles of 



Fig. 13. Left, flask of heated soil with abundant growth of Pyronema. 

 Right, same soil unheated but otherwise treated in the same manner produces 

 no growth. 



wood or brush have been burned. The most common of these 

 is the well-known Pyronema, first encountered by the writer 

 during his early work in Iowa. Without stopping to investigate 

 the matter it was simply assumed that this fungus occurred on 

 burnt places because it preferred ashes to grow on as other 



