ANALYTICAL KEY 



TO THE SUBORDERS, FAMIlilES AND GENERA OF 

 THE 



NOETH AMERICAN PYEBNOMYCETES AN: 

 HYSTERIACEAE. 



The Nat. ORDER PYRENOMYCETES embraces thos 

 ' fungi in which the asci and sporidia are enclosed in a peritheciun 

 and is divided into 4 SUBORDERS as follows : 



Peritheeia superficial, astomous, membranaceous, 



mostly on a subiculum. - Perisporiaceai 



Peritheeia carnose, or membranacep-carnose, 



ostiolate, bright cqlored (red, yellow, etc.,) 



hot black. • • - ffypocreaceoi 



Peritheeia black or brown, mostly ostiolate, of 

 various consislence, membranaceous, co- 

 riaceous, carbonaceous, woody or corky, but 

 not carnose; stroma when present not car- 

 nose, dark colored outside, often white 

 within. - - Sphaeriaceai 



Stroma always present, of firm texture not carnose, 

 black outside. Peritheeia reduced to mere 

 cells in the stroma. DotMdeacea^ 



KEY TO THE FAMILIES. 



SUBORDER PERISPORIA.CEAE. ^ 



Mycelium of colorless, interwoven threads. Per- 

 itheeia seated singly on the mycelium, subglobose, 



