216 



Mycologia 



sents a more recent development than a similarly 2-lobed one. 

 In any case these assumptions make it possible to explain very 

 satisfactorily the inter-relationships of the four known species 

 which clearly represent the highest type of development in the 

 genus Corynelia. These species (C. oreophila, C. brasiliensis, C. 

 portoricensis and C. jamaicensis) are restricted, as far as is 

 known, to the Western Hemisphere, and in all of them the upper 

 portion of the perithecium is marked on the surface by one or 

 more prominent grooves along which dehiscence takes place. 

 They constitute a definite group of closely related species, and 

 it is of interest to speculate concerning the character of the 

 parent stock from which they arose. Here as in the more prim- 

 itive species of Corynelia the asci were doubtless 8-spored. The 

 perithecium was usually 2-lobed at the apex but occasionally a 

 3-lobed individual occurred. There was also the tendency for 

 asci to occasionally bear less than eight spores, though this phe- 

 nomenon was not common or pronounced. From this parent 

 stock along one line C. oreophila arose by the increasing tendency 

 toward the occurrence of 3-lobed perithecia.. This species as it 

 exists today is characterized by 3-lobed perithecia, though an oc- 

 casional 2-lobed individual shows the retention of the ancestral 

 character. The asci like those of the parent stock are 8-spored 

 though occasional asci contain a smaller number of spores. From 

 the parent stock along a neighboring line C. brasiliensis arose by 

 the development on the perithecium; of a wedge-shaped apex. In 

 all other respects this species is like C. oreophila. The occasional 

 occurrence on the stroma among the typical perithecia of a few 

 small, poorly developed individuals with 2-lobed and 3-lobed 

 apices exactly like those of C. oreophila constitutes reversion to 

 the ancestral condition. 



Along a third line C. portoricensis and C. jamaicensis arose 

 from the parent stock by the increasing tendency for the asci to 

 be few-spored. In C. portoricensis the form of the perithecium 

 may be assumed to have changed relatively little. The majority 

 of the perithecia are 2-lobed at the apex ; a few are 3-lobed. The 

 asci, however, have changed pronouncedly. The tendency seen 

 in the parent stock for the number of spores in the ascus to de- 



