Central American Pyrenomycetes. 395 



The perithecia are small cases, so to speak, exhibiting usu- 

 ally a spherical or flask-shaped form, and are lined with hy- 

 menium in the lower part and are generally pierced at the 

 apex, the opening being called an ostiolum. The perithecia 

 are often prolonged around the ostiolum into a neck, or beak, 

 the better probably to disperse the sporidia. The perithecia 

 may be superficial or sunk more or less into the matrix or more 

 or less sunk in a body like the perithecia in substance and 

 varying in size and shape, known as the stroma. The stro- 

 ma maj' consist of a transformed part of the matrix. The 

 hymenium consists of two kinds of elongate cells. One is sac- 

 like, the asci, in which are produced the sporidia. The 

 sporidia are reproductive bodies, generally eight in number, 

 and in many cases they have proven to be the product of fer- 

 tilization. The cells of the other kind are rather slender and 

 often are much like the asci, among which they are situated. 

 They are thought by some to be abortive asci and are called 

 paraphyses. 



The secondary or metagenetic phases often cover the form- 

 ing stroma, forming on the aerial branches of the mycelium 

 conidia (gonidia) or in the forming perithecia or similar con- 

 ceptacles, at the apex of hyphte, so-called pycnidia. It is 

 commonl}' conceded (although in but few cases proven) that 

 their growths are a part of the plant on which they appear, 

 although in some cases a parasite form of some other fungus 

 appears on the growing Pyrenomycete. The conidia, gonidia 

 and pycnidia are asexual reproductive bodies. 



The Pyrenomycetes given in this paper were collected in 

 Nicaragua by the expedition sent out last December by the 

 State University of Iowa. (See Mr. B. Shimek's article in 

 this Bulletin.) 



The name of the locality is given with each species follow- 

 ed by the initials of the person or persons collecting it. If 

 the species was collected in two localities, the names of the 

 two places are given. 



A large majority of the species were collected during the 



