THE FIMETARIALES OF OHIO 
79 
ORDER FIMETARIALES 
Perithecia superficial or deeply sunken in the substratum, usually 
without stroma, but, when the latter is present, perithecia immersed with 
the necks slightly protruding, subglobose, ovoid or flask-shaped, dark-col¬ 
ored, black or nearly so, occasionally dark-brown, smooth and naked or 
thickly clothed with bristle-like or flexuous hairs which are simple or 
branched and often overtop the perithecia forming a dense tuft; perithe- 
cial wall thin, membranous to coriaceous. Paraphyses persistent or evan¬ 
escent. Asci 4-many-spored, evanescent and scarcely visible in mature 
plants, or persistent but delicate. Spores simple or compound, often 
surrounded with a hyaline gelatinous and rather evanescent envelope or 
with a long apiculus at each end, usually dark-colored, yellow to olivaceous, 
dark-brown or black, the compound spores often deeply constricted at the 
septa. Plants growing on decaying materials of various kinds, especially 
on the dung of animals. 
Perithecia overtopped with a dense mass of hairs; paraphyses 
and asci evanescent. Family 1. Chaetomiaceae 
Perithecia not overtopped with hairs; paraphyses and asci 
persistent but delicate. Family 2. Fimetariaceae 
FAMILY 1 . CHAETOMIACEAE 
Perithecia scattered or gregarious, superficial, free or adnate, generally 
seated on a superficial mycelium, usually with an ostiolum at the apex, 
pale-brown to black, with a thin, membranous wall, thickly clothed with 
hairs, the basal ones functioning as rhizoids, the apical ones usually longer 
and coarser, branched or simple, forming a tuft. Paraphyses evanescent. 
Asci clavate, evanescent, seldom visible in a mature specimen. Spores 
simple, ellipsoid or ovoid to subglobose, more or less compressed, usually 
more or less apiculate at the ends, with a cup-like depression on one side 
which causes them to appear spindle-shaped or narrowly ellipsoid in profile. 
Species all saprophytic, infesting a firm rather moist substratum, such as 
decaying parts of plants or dung of animals. 
1. Chaetomium Kunze & Schmidt, Myk. Hefte 1: 15. 1817. 
Ascotricha Berk. Ann. Nat. Hist. 1; 257. 1838. 
Perithecia superficial, usually with an ostiolum, and having an apical 
tuft of hairs or bristles covering the exposed surface of the thin and 
membranous wall; asci club-shaped, evanescent; spores simple, hyaline to 
dark-brown, more or less compressed. 
Type species, Chaetomium globosum Kunze. 
Apical hairs all simple. 
Hairs flexuous. 
Hairs circinate or subcircinate. 
Hairs circinate and not swollen at the base. 
1. C. murorum 
