212 Mycologia 



question whether or not these forms really comprise a natural 

 order. On account of the tropical distribution of many of the 

 species our knowledge of the Perisporiaceae and Microthyriaceae 

 is recognized to be very imperfect, and it may be safely assumed 

 that further study will result in pronounced changes in their 

 classification. It is possible that many of the species embraced 

 in the Perisporiaceae are more closely related to the Sordariaceae 

 and other lower Sphaeriales than they are to the Microthyriaceae, 

 many of which in turn might well be relegated to the Phacidiales. 

 The genus Diplocarpon, as pointed out by Wolf (56) may indeed 

 be regarded as furnishing a transition to this group. 



The Sphaeriales, on account of their possession of a definite 

 ostiolum may be assumed to be more highly developed than the 

 Perisporiales. Still it is probable that they had their origin in 

 fungi similar to the Perisporiaceae, and perhaps developed from 

 these along several different lines. 



The Coryneliaceae as constituted in the present paper cannot 

 be placed with entire satisfaction either in the Sphaeriales or in 

 the Perisporiales as delimited by Lindau and other authors. The 

 absence of superficial mycelium and the development of the peri- 

 thecia on an erumpent stroma render them unlike the Peri- 

 sporiales, while the absence of a true ostiolum excludes them 

 from the Sphaeriales. The problem is further complicated by 

 the existence in the single genus Corynelia of two distinct types 

 of dehiscence. In this connection it should be noted that although 

 the more primitive of the two sorts of dehiscence has its counter- 

 part in certain of the Perisporiaceae, the other and clearly more 

 specialized method is wholly unlike anything hitherto described 

 for any of the pyrenomycetes. A consideration of all the avail- 

 able data in the light of the questions involved mak^s it evident 

 that the grounds for the inclusion of the Coryneliaceae among the 

 higher Sphaeriales in the neighborhood of the Cucurbitariaceae 

 are wholly untenable. These fungi are clearly of an essentially 

 different and more primitive type. They are probably more 

 closely related to the Perisporiaceae than to any other group, and 

 their development of a unique type of dehiscence indicates an 

 ancient origin. 



