CONTRIBUTIONS FROM THE CRYPTOGAMIC LABORATORY OF 

 HARVARD UNIVERSITY. — XL VII. 



PRELIMINARY DIAGNOSES OF NEW SPECIES OF 

 LABOULBENIACEAE. — IV. 



By Roland Thaxter. 



Received May 6, 1901. Presented May 8, 1901. 



Additional material illustrating the well-marked generic type de- 

 scribed in a former paper as Mbnoicomyces renders necessary some 

 modification of the original diagnosis, as well as the separation of several 

 species in a second nearly allied genus, which I have called Eumonoico- 

 myces (E. Papuamis being taken as the type), that is well characterized 

 not only by constant differences in the structure of the peculiar anther- 

 idium, but also by reason of certain differences in gross habit which are 

 constant in normal forms of all three of the known species, one of which, 

 E. invisibilis, was formerly placed by me in Mbnoicomyces. 



EUMONOICOMYCES nov. gen. 



Receptacle consisting of a basal and subbasal cell ; the latter producing 

 terminally a sterile appendage and laterally a fertile branch (abnormally 

 more than one) the axis of which is coincident with that of the receptacle 

 from which it is not distinguished and consists of a series of superposed 

 cells which may bear a sterile appendage, an antheridium, or an anther- 

 idium and a perithecium ; the three terminal cells usually bearing these 

 organs in the order mentioned. The antheridia consisting of a single 

 stalk-cell, and a single, often obscure, basal cell; the body of the antherid- 

 ium consisting of a series of numerous antheridial cells in four (?) vertical 

 rows which extend obliquely inward and upward, emptying into a com- 

 mon cavity, and replace entirely the two tiers of wall-cells and the anther- 

 idia of Monoicomyces ; the terminal cells growing upward directly to 

 form four unequal sterile terminal appendages, similar to those of 

 Monoicomyces. 



