Arnium heterochaetum (Griffiths) J. C. Krug & Cain 1972

Pleurage heterochaeta D. Griff. Mem. Torrey Club 11 : 86. 1901
Philocopra heterochaeta Sacc. Syll. Fung. 17 : 606. 1905.
Perithecia superficial or with base slightly sunken, scattered, thin, membranaceous, olivaceous in sunken portions but fuscous above, with blackened apex, somewhat transparent, about 450 X 700 i ; all exposed portions except the black, bare, papilliform beak covered with short, blunt, transversely or obliquely septate, agglutinate hairs, which are prominent around the base of the beak and decrease to mere scattered papillae downward ; uniformly scattered among the latter are long, filiform, flexuous, septate, brown hairs, which gradually become transformed below into the rhizoids, which ramify through the substratum ; asci 16-spored, cylindricclavate, contracted and narrowly rounded above and contracted below into a short, stout stipe, 34-40X230-240^, very evanescent; paraphyses exceedingly ventricose, agglutinate and not at all mixed with the asci, often very indistinct and appearing more like a tissue lining the perithecium than like filaments; spores 2-seriate, ellipsoid, broadly rounded at both ends, 18-20 X 27-34 ii ; primary appendages entirely wanting, the apex of the spore tipped with 2 awl-shaped, parallel or slightly divergent, rather firm, gelatinous appendages, which in the ascus are curved so as to appear as one; lower end of the spore bearing 2 similar but ^uch more delicate, curved and variously twisted appendages.
On cow dung.
Type locality : Family, Montana. Distribution ; Known only from the type locality.