Parasitic Fungi of Illinois. 241 



Peridermium, Link. 



Spores one-celled, in chains or vertical rows, without pedi- 

 cels; sorus inclosed in a variously-shaped pseudoperidium, which 

 protrudes through the ruptured substratum and bursts irregu- 

 larly: with spermagonia. On Con if era'. 



This so-called genus is composed of probable ascidioforms 

 of Melampsora. Chrysomyxa and CoJeosporium species. The 

 mycelium is. however, perennial in the bark and medullary 

 rays of coniferous trees, from which the fruit-form may be an- 

 nually produced during seventy or more years, — the parts of 

 the host in the meantime becoming variously deformed, and the 

 growth more or less seriously reduced. 



Not yet observed in Illinois. 



Endophyllum, Lkyeille. 



Spores one-celled, produced in chains or vertical rows, 

 without pedicels, the sorus inclosed in a pseudo])eridiuni im- 

 mersed in tlue substratum: with spermagonia. 



This genus was at first separated from jEcidium only on 

 account of the immersed pseudoperidia. which, unlike those of 

 the latter genus, do not protrude through the ruptured epider- 

 mis to form a separate cup-like organ; but later investigations 

 have shown that the sjiores in germination emit a true promy- 

 celium bearing sporidia. altogether similar to the germination- 

 development of the teleutospores of Piicrinia and the other 

 genera of UrecJinea'. The mycelium in the newly affected plant 

 survives the winter and fruits the next spring. 



Xo species yet observed in Illinois. They may be looked 

 for on various species of Crassuhice<v. and perhaps on those of 

 Eiip}torhi((cea\ 



