120 Natural History Bulletin. 



V. TRICHIACEiE. 



Sporangia single, seldom united to form an aethalium. 

 Peridial thickenings, calcareous granules (usually) and colu- 

 mella none. Capillitium of tubular threads, simple, branching 

 or united in a net; free or united with the peridium or the 

 stipe. Spores and capillitium usually yellow or red, more 

 rarely whitish or brown, not violet. 



KEY TO SUB-FAMILIES. 



A. Capillitium plain, Pekich^ne^. 



B. Capillitium-threads with the walls variously thickened, . Arcyrie^. 



C. Capillitium-threads furnished with spiral bands, .... Trickier. 



A. PerichcBnece. 

 This sub-family contains but a single genus, viz: 



PERICH^NA, Fries. 



Sporangia sessile, generally opening with a lid. Peridium 

 simple or double; when double the outer fragile with lime 

 granules, the inner thin membranous. Capilhtium with thin 

 smooth walls, the filaments springing from the upper wall 

 and either branched or simple. Spores yellow. 



9. Perich^na corticalis, Batsch. Plate II, Figs, i, la 

 and lb. 



Sporangia sessile, gregarious, flattened, hemispherical. Pe- 

 ridia simple, opening by a lid (dehiscence circumscissile), the 

 upper part chestnut brown, the lower almost black. The 

 capillitium feebly developed, smooth, attached to the lid and 

 usually coming away with it, bringing the brilliantly yellow 

 spore mass, and leaving a delicate shining cupule adherent to 

 the substratum. Spores yellowy smooth, .010-.012. On and 

 under the bark of dead elms of various species. 



A very handsome litttle species occuring rarely v;ith us, or 



