40 The North American Cup-Fungi 



yellowish or greenish at least when young, very soft and fleshy, 

 the paraphyses and asci often surrounded by a mucilaginous, 

 yellowish or greenish slime, never conspicuously hairy, occurring 

 on dung or more rarely on soil, etc. ; asci broad-clavate, operculate, 

 strongly protruding at maturity and very conspicuous on account 

 of their large size and the dark-colored spores which they contain ; 

 spores becoming some shade of violet or purple as they mature, 

 later brown or occasionally blackish and opaque, ellipsoid or 

 rarely almost globose, smooth or sculptured, spore-sculpturing 

 taking the form of warts or reticulations, the reticulations con- 

 sisting of ridges or crevices; paraphyses variable. 



Spores free in the ascus. 9. Ascobolus. 



Spores united in a ball in the ascus. 10. Saccobolus. 



Tribe 3. Aleurieae. Apothecia small to medium or large, 

 usually bright-orange or red, more rarely dark-brown, sessile or 

 stipitate, growing on soil or humus, naked or hairy; hairs soft 

 and flexuous or bristly, hyaline or brown; asci cylindric or sub- 

 cylindric, operculate, 8-spored; spores hyaline to pale smoky- 

 brown, at maturity sculptured; spore-sculpturing consisting of 

 ridges which usually give rise to very regular net-like reticula- 

 tions; paraphyses usually strongly thickened above and colored. 



Apothecia not clothed with colored hairs. 



Hymenium bright-orange; spores hyaline. 11. Aleukia. 



Hymenium dark-brown ; spores smoky-brown. 12. Aleurina. 



Apothecia clothed with colored hairs. 13. Melastiza. 



Tribe 4. Humarieae. Apothecia small, not usually ex- 

 ceeding 1 cm. in diameter and often less than 1 mm., soft and 

 fleshy or rarely slightly tough, scutellate to discoid or occasionally 

 with the hymenium strongly convex, usually sessile, occurring 

 on the dung of animals, soil, or debris; asci cylindric to clavate 

 or ovoid, in a few cases marked with a ring or collar near the 

 apex, operculate or bilabiate, 4- to many-spored; spores ellipsoid, 

 hyaline or subhyaline, smooth, or minutely sculptured; pa- 

 raphyses variable in size and color. 



Apothecia closely attached to the substratum to the 



extreme margin, usually occurring on wood. 14. Psilopezia. 



Apothecia attached to the substratum by the center 

 only, occurring on soil, humus or the dung of 

 animals. 

 Vegetative mycelium superficial, forming a con- 

 spicuous web on burnt places. 15. Pyronema. 



