12 Cincinnati Society of Natural Histoiy. 



outer peridium thick, fleshy-coriaceous, at maturity splitting from the 

 apex downward into several segments which become reflexed ; inner 

 peridium thin, membranaceous then papyraceous, supported on sev- 

 eral short pedicels, and emitting the spores through one to many 

 mouths. Threads of the capillitium simple or rarely branched, taper- 

 ing to each extremity ; spores globose, minutely warted, brown. 



A genus of very singular plants, comprising at present but two 

 species, the individuals of which are rarely met with. 



I. M. coliforme, Dicks. Peridium subglobose, whitish, wrinkled 

 and scaly; outer peridium multifid, reflexed; the segments 4-10, 

 usually 7, acute at the apex; inner peridium globose or depressed- 

 globose, gray or brownish, silvery shining, minutely warted; the 

 small mouths numerous (3-50), at first papilliform, then a little ele- 

 vated and ciliate, scattered irregularly over the upper surface. Threads 

 of the capillitium simple or very rarely branched, tapering to each 

 end, brown; spores globose, minutely warted, brown, 5-6 mic. in 

 diameter. See Plate I, A. 



Growing in sandy soil. Colorado, Chas. H. Peck. Inner peridium 

 1-2 inches in diameter, the outer peridium expanding to a breadth of 

 3-6 inches, the small pedicels 2-5 mm in hight. The plant is said to 

 be at first sunk deep in the ground, and therefore is probably con- 

 nected with the soil by a superficial filamentous mycelium. The 

 related M. columnatum, Lev., which grows in Chili, emits the spores 

 by a single fimbriate mouth. 



Genus IV. Geaster, Mich. 



Mycelium filamentous or fibrous, much branched and interwoven 

 with the soil. Peridium subglobose, composed of two distinct per- 

 sistent coats; outer peridium thick, fleshy-coriaceous, at first closely 

 investing the inner but discrete, at maturity splitting from the apex 

 downward into several segments which become reflexed; inner perid- 

 ium thin, membranaceous then papyraceous, sessile or with a short 

 pedicel, dehiscent at the apex by a single mouth. Capillitium taking 

 its origin from the inner surface of the peridium and also from a dis- 

 tinct central columella, which arises from its base ; threads simple, 

 long, slender, thickest in the middle and tapering to each extremity, 

 fixed at one end and free at the other ; spores small, globose, minutely 

 warted, brown. 



Plants which grow just beneath the surface of the soil ; when the 

 outer peridium bursts the segments become reflexed and lift the inner 



