20 Cincinnati Society of Natural History. 



short or entirely wanting. Capillitium much expanded after 

 dehiscence, globose or obovoid, pale red to brownish in color; 

 the threads uniform in thickness, about 4 mic, the surface 

 with a series of prominent half-rings with mingled warts and 

 spines, which wind around the thread in a long spiral. Spores 

 globose, even, 6-8 mic. in diameter. 



Growing in small clusters on old wood. A small species, 

 the capillitium expanded 1-2 mm., the stipe extremely short, 

 or altogether absent. 



4. Arcyria nutans. Bull. Sporangium cylindric ; the 

 calyculus small, granulose, ribbed and sulcate. Stipe very 

 short, arising from a common hypothallus. Capillitium 

 greatly elongated after dehiscence, cylindric, drooping and 

 pendulous, pale yellow or pale ochraceous ; the threads 3-4 

 mic. in thickness, the surface covered with spinules, among 

 which are rings and half-rings, with an indistinct spiral 

 arrangement. Spores globose, even, 7-9 mic. in diameter. 



Growing on old wood. The capillitium elongated 4-8 mm., 

 the stipe very short. A very conspicuous species h\ reason 

 of its long pale yellow capillitium. 



i^2. Plectanella. Capillitium erect, firmly attached by 

 numerous threads, which issue from the interior of the stipe, 

 but are connate with the wall of the calyculus, after dehis- 

 cence not much expanded : the meshes at the surface of the 

 network much smaller than those within, folded back and 

 forth, narrow and irregular, their threads denselj' warted or 

 spinulose ; the meshes of the interior much larger open and 

 expanded, their threads with minute scattered warts or per- 

 fectly smooth. 



5. Arcyria cinekea, Bull. Sporangium ovoid or oblong- 

 ovoid; the calyculus very small. Stipe long, erect, cinereous, 

 becoming blackish, standing on a thin hypothallus. Capilli- 

 tium not much expanded after dehi.scence, ovoid-oblong, erect, 

 pale cinereous, sometimes pale yellowish ; the external threads 

 densely spinulose, 2-3 mic. in thickness; the threads of the 

 interior thicker, 3-5 mic, and very minutely warted or quite 

 smooth. Spores globose, even, 6-s mic. in diameter. 



Growing on old wood. Capillitium 1-2 mm. long, the stipe 

 about the same length. 



