NEW DIMORPHOMYCETEAE. 251 



Dimeromyces nigricaulis nov. sp. 



Male uidlvidual subhyaline; the receptacle consisting of two or 

 three cells; erect, of almost uniform diameter, the septa hardly oblique, 

 the subbasal bearing the antheridium, a second sometimes arising 

 from the basal cell of the appendage; which is not distinguished from 

 the receptacle, and is separated from the short one or two celled 

 abruptly narrower distal portion by a tluck black constricted septum. 

 Antheridium erect, curved outward distally, the stalk-cell well devel- 

 oped and conspicuously blackened distalh-; the outcurved neck rela- 

 tively rather stout and short. Receptacle including basal cell of 

 appendage and exclusive of foot 25 X 4.5 n. Antheridia 25 X 7.5 /x. 

 Free appendage above black septum 12 X 4 ^t. 



Female individual uniform dirty pale yellowish brown, the receptacle 

 somewhat darker. Receptacle consisting of usually six subequal cells, 

 the four middle ones somewhat flattened and oblique, the subterminal 

 one producing the usually single perithecium; the rest, except the 

 basal, giving rise to appendages the basal cells of which each produce 

 two branches transversely but somewhat irregularly paired, rather 

 short, stout, and divergent from the base of the perithecium, distin- 

 guished by thick black constricted septa: the basal cell of the pri- 

 mary appendage hardly longer than broad, the free appendage short, 

 few- or even one-celled, a secondary basal cell normally separated 

 obliquely on the inner side and bearing a usually four-celled free 

 appendage separated by a similar black septum. Perithecia as a rule 

 slightly and evenly arcuate throughout, abruptly bent outward from 

 the insertion, stout, very slightly broader distally, the stalk-portion not 

 distinguished, the tip clearly differentiated by slight subtending eleva- 

 tions, associated with a slightly deeper suffusion of this region, the 

 inner margin more convex, somewhat abruptl\' narrower and slightly 

 tapering to the short apex, which is distinguished only by the promi- 

 nently rounded inner lip-cell. Perithecia 200-235 X 20-22 /x. Recep- 

 tacle 70-85 X 22 M- Appendages 40-60 X 8-8.5 (jl. Total length 

 to tip of perithecium 300 /x, more or less. 



On the elytra of Diacantha flarrsccns \Vs. No. 3069, Kamenm, 

 W. Africa. 



Apart from other characters which might be variable, this species 

 seems distinguished by the blackened termination of the stalk-cell of 

 the antheridium, which is present and characteristic in the three indi- 

 viduals examined. A dozen females are available which show no 



