16 THAXTER. 



toward its distal end, rather large; cell i normal, slightly longer than 

 broad, subsymmetrieal. Perithecium relatively short, about one 

 fourth free; the tip curved abruptly over a rounded concavity formed 

 by a large, broad, blunt, erect, tooth-like external process: the small 

 somewhat compressed apex subtended on the inner side by a flattened 

 elevation resulting from a thickening of the wall. Spores about 

 45 X 2.5 /x. Perithecia about 70 X 20 n, exclusive of the tooth-like 

 process which is 11 X IS X 22 /x. Total length to tip of perithecium 

 12-150 X 30-35 M- 



On the margin of the right elytron of a small dark dityscid, Manila, 

 P. I. (Banks), No. 2409. 



This species, like the preceding which occurs on the same host, 

 lacks the usually secondary appendiculate cell, which is not separated 

 from the end of cell/. It is well distinguished by the abrupt concavity 

 formed between the tip of the perithecium and the prominence which 

 subtends it externally. It is further peculiar from the unusual de- 

 velopment of cells d and c which are relatively much more elongate 

 than in any other described species. 



RiCKIA. 



Owing to the considerable variety and diversity of the hosts at- 

 tacked by species of this genus it promises to become one of the largest' 

 among the Laboulbeniales. I have referred in a previous paper, 

 (These Proceedings, 47, 10, 1912), to the diversity presented by the 

 different forms which have thus far come under m}' observation, and 

 to their considerable ^'ariations from the type form as it is illus- 

 trated by R. Tf^asmanni of Europe. A study of very copious material 

 has led me to believe, however, that in this as in other groups of which 

 our knowledge is still fragmentary, it is far better to interpret generic 

 types with great liberality. I have, therefore, preferred to make the 

 genus Rickia a rather comprehensive one, the A'ariations as to antheri- 

 dia, character of the axis, whether branched or simple, triseriate or 

 biseriate, which are the more important matters in which divergence 

 is observable, being so combined or transitional that a subdivision 

 has seemed to me distinctly undesirable. 



As in the paper cited above, I have called the appendage which 

 always terminates the axis of young individuals and which, together 

 with its two-celled base, may be carried up by the developing receptacle 

 or left near the base as a lateral appendage, the primary appendage. 



