no 



THE ASCOMYCETES 



Included in the Pseudosphaeriaceae are such genera as Pleo- 

 spora, having approximately 300 species, Didymella, having over 

 200 species, ^Leptosphaeria, having over 500 species, and Pyre- 



FiG. 62. Section of stroma of Botryosphaeria ribis, showing a perithecial 



locule with asci and paraphyses. 



nophora. Most of them are saprophytic on plants. Some species 

 of Pleospora have been shown to possess conidia belonging to 

 Alternaria and iMacrosporium, in both of which imperfect genera 

 are many plant pathogens. Various grasses are parasitized by 



