270 



THAXTER. MONOGRAPH OF THE LABOULBENIACE^E. 



branches, consisting of a single basal cell, from which arises the stalk-cell of the perithecium on the inner, 

 and that of the antheridium on the outer side. Stalk-cell of the perithecium narrowed at the base, the 

 narrow portion red-brown, expanding above and hyaline. Peritheciinn somewhat asymmetrical or bent, 

 deeper straw-colored, tapering gradually to the blunt tip, which is hardly distinguished. Antheridium 

 of the normal type, the distal appendages usually two, one sometimes exceeding the tip of the perithecium. 

 Total length to tip of perithecium 150-200 Perithecium 90-110 X 30 fi, the stalk-cell 35 X 46 /i. 

 Spores about 35 X 4 fi. 



On the abdomen of Homalota sp., infesting species of Lactarius, Kittery Point, Maine. 



This is a rather rare species, occurring near the tip of the abdomen of one of the larger mycophilous 

 HomaJolw. It is most nearly allied to M. Homolata, from which it differs in its slender form, large size 

 and single primary appendage, which is distinguished at its base by a black septum. It is subject to 

 some variation, the more normal form represented in the figures, being often modified through the pro- 

 duction of only one perithecium or of more than two. The red brown suffusion at the base of the perithe- 

 cial stalk-cells is also peculiar. 



Monoicomyces nigrescens Thaxter. Plate XXXVI, figs. 1-4. 

 Proc. Am. Acad. Arts and Sci., Vol. XXXVIII, p. 10. June, 1902. 



Receptacle minute, its basal cell hardly distinguishable above the foot, bearing distally a simple 

 appendage the basal cell of which is hyaline, the subbasal somewhat longer than those above and deeply 

 tinged with blackish brown below. Fertile branches two or more, usually four, each consisting of a single 

 cell which bears an antheridium terminally and a perithecium subtenninally : the primary branches 

 normally two, lateral and symmetrical, edged externally with blackish brown, the blackening contrasting 

 and continuous with a similar coloration which extends to the tip of the primary antheridium: the second- 

 ary fertile branches arising, when present, between the primary and resembling the latter, except for the 

 absence of the black discoloration; the whole group of branches forming, with their closely crowded 

 antheridia and perithecia, a compact, fan-like, usually symmetrical tuft. Antheridia relatively long, 

 suffused with smoky brown, more deeply blackish externally, the secondary ones with a more or less con- 

 spicuous foot-like blackened base; the stalk clearly two-celled, shorter than the main body; only two of 

 the cells separated from distal cells growing upward to form two unequal terminal appendages, which are 

 smoky brown, darker about their blackened basal septa, the cells immediately below them projecting up- 

 ward very slightly on either side. Perithecia furnished w r ith variably developed stalk-cells the bases of 

 which are blackened, but which are otherwise hyaline, as is the rest of the rather short, often stout, sub- 

 conical, bluntly pointed perithecium. Perithecia 60-75 X 22-25 ji; the stalk-cell 12-55 /z. Antheridia 

 including stalk, 35 \i, the appendages 35-50 fi. Total length 100-160 ji. 



At the tip of the abdomen of Calodera sp. and of Tachyusa sp.; Intervale, N. H., No. 1357; Kittery 

 Point, Maine. The hosts frequenting fleshy fungi. 



This species is not uncommon on minute staphvlinids inhabiting decaying Lactaiii and other fleshy 

 fungi, but from its small size, dark color and flat appressed habit, it is difficult to find. It is possible that 

 the secondary fertile branches arise as in M. Akochara> from the proliferation of the primary ones, but in 

 some cases at least they seem to arise directly from the subbasal cell of the receptacle. The species is 

 well marked and recognizable from its marginal suffusions. 



Monoicomyces Aleochar^e Thaxter. Plate XXXVI, figs. 5-7. 

 Proc. Am. Acad. Arts and Sci., Vol. XXXVII, p. 24. June, 1901. 



Pale amber, shading to amber-brown. Receptacle, together with the foot and the basal cell of the 

 terminal appendage, forming a heart-shaped body, blackened below, bearing terminally the median, rigid, 

 slender, almost wholly opaque, black continuation of the primary appendage which is abruptly distin- 

 guished from its broad basal cell : the subbasal cell of the receptacle small, triangular when viewed side- 

 wise, giving rise to two fertile branches, the short small basal cells of which give rise at once each to two 



