THE HYPOCREALES OF NORTH 

 AMERICA— I 



Fred J. Seaver 

 (With Plates 4 and 5, Containing 33 Figures) 



The Hypocreales might be briefly defined as the bright-colored 

 sphaeriaceous fungi, the bright color being the most conspicuous 

 character of this order, the early described members of which 

 were included in the genus Sphaeria. In addition to color, the 

 plants of the order are characterized by membranaceous peri- 

 thecia and fleshy stromata, when the latter are present, as opposed 

 to the carbonaceous perithecia and stromata and, usually, the 

 black color of the true pyrenomycetes. While no one of these 

 characters is sufficient in itself, taken together they are quite 

 definitive of the order, which appears to be a well-marked natural 

 group. 



The plants of this order exhibit in their life-histories two 

 phases, the conidial and ascigerous, the so-called imperfect fungi 

 representing the conidial phase of many of the species. In no 

 group of fungi is there more need of a close and critical study 

 of the life-histories of its individual members than in the one now 

 under consideration. In a few cases this has been done, with the 

 result that some of the species have been found to be of extreme 

 economic importance in their relation to plant diseases, and doubt- 

 less the same fact will be discovered with reference to other 

 species when critical work of this kind is extended to those forms. 

 While the conidial phase in a part of the order is obscure, in 

 others it is often profuse, forming a distinct fleshy or cottony 

 stroma, on which are produced first conidiophores and conidia, 

 and later perithecia, the latter containing the asci and spores. 

 The characters of the conidiophores and conidia are very variable 

 and will furnish much valuable information as to the natural rela- 

 tionship of the various members when the life-histories of the 

 species are better known. In one group, which is here treated as 

 a tribe, the stromata develop from a sclerotium, the latter term 



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