30 



ulations obscure; appendages few, 8-12. dark colored, except the 

 branches, scarcely equal to the diameter of the perithecium, 4-6 times 

 regularly dichotomous, branches short and rather thick, tips recurved. 

 Asci 5-8, oval or ovate, pedicellate, rather small, 35 x 55 ji. Sporidia 

 uniformly 8, small. 



On the "erineum" caused by a Pbytoptus (mite), on the lower 

 sides of leaves of Fagusferruginea. 



The erineum is usually very common wherever the tree grows, 

 but the fungus seems to be rare. It has also been collected by Earle 

 in Illinois and Indiana. See Fungi Europmi, No. 3245. 



M. Astragali, (DC.) 



Peck reports M. holosericea, (Wallr.) Lev. a synonym for M. 

 Astragali (25th Report N. Y. State Mus., p. 95), on Astragalus 

 Cooperi, but this species does not seem to have been elsewhere col- 

 lected in America. Is it possible that a poorly marked specimen of 

 M. diffusa was thus identified ? 



M. Lycii, (Lasch.) 



Microsphcera Mougeotii, I^ev. 



This is inserted on the sole authority of the publication in Gre- 

 villea IV, p. 160, where the fungus is said to have been found on Des- 

 modium Dillenii. Undoubtedly an incorrect determination. 



FAMILY. PERISPORIEJl. 



Mostly without any stroma but with a strongly developed, brown, 

 persistent, conidia-bearing mycelium, which, however is sometimes 

 inconspicuous or evanescent. Perithecia spherical or depressed, mem- 

 branaceous or coriaceous, generally astomous, always superficial. 



This Family is made up of rather heterogeneous material, the dif- 

 ferent members not being closely allied so as to form a well character- 

 ized natural group, as in the preceding family. 



KEY TO THE GENERA. 



Mycelium present. 1. 



Mycelium scanty or wanting. - - - - - 2. 

 Mycelium black, dense. 3. 



1. Mycelium thin, arachnoid. - - - . Saccardia. 

 Mycelium yellow. ----- Eurotium. 

 Mycelium light colored. - Myriococcum. 



2. Perithecia scattered, subglobose. - - Perisporium. 



*Winter, in Die Pilze, includes here also Aspergillus and Penicillium, of which till recent- 

 ly, only the conidial stage was known. In these genera perithecia are wanting, the asci being 

 inclosed in a tuber-like sclerotium which is developed from the mycelium. 



