260 BRYACE^. . [Psilopilum. 



conical, with a short incurved beak. Teeth long, some of them 

 bipartite, thin. Diaphragm of the columella funnel-shaped. 



1. P. arcticum, Brid. Stems short, simple : capsule ferru- 

 ginous, black when old. — Bryol. Univ. ii. 96. Oligotrichum 

 IcBvigatiw), Bruch & Schimp. Bryol. Eur. t. 414. 0. glahratum^ 

 Lindb. Obs. Polytrich. in Faun. Flor. Fenn. ix. 143. 

 Hab. Peat bogs; Labrador, Greenland and Arctic America. 



96. POGONATUM, Beauv. (PI. 3.) 

 Plants short and simjile, or robust and long, with dendroid 

 ramification ; fertile plants arising from subterranean stolons 

 or from a radical prothalliuni, dividing by innovations from the 

 middle of the stems or from under the perichatium. Flowers 

 dioecious ; male flowers proliferous. Leaves clasping at base, 

 open, unaltered by moisture ; costa covered with very numerous 

 lamellae occupying nearly the whole lamina, rendering the 

 leaves hard and coriaceous ; margins spinulose-serrate. Cap- 

 sule regular, erect, or cernuous. Peristome of 32 teeth, orange 

 in the middle. 



§ 1. Aloidea. Plants short, sim2:)le, gregarious or scattered, 

 radiculose at base. 



1. P. brevicaule, Beauv. Plants short, scattered, growing 

 out of a persistent dark green confervoidnl prothalliuni ; stem 

 simple, very short, ^ to 1 cm. long, densely foliate: lower 

 leaves small, appressed, ovate, short-pointed, the upper lai-ger, 

 erect-open, clasping at the enlarged base, lanceolate-acuminate; 

 perichtetial leaves very long, oblong, membranaceous, obscurely 

 costate at base, more abruptly nai-rowed into a long erect 

 obtusely serrate acumen ; lamella; capitate-claviform in trans- 

 verse section : male plants in short rooting buds ; perigonial 

 leaves erect, curved back from above the middle, imbricate, 

 broadly obcordate, with a thick medial nerve excurrent into an 

 inflated mucronate point : calyptra very hairj'-, covering the 

 capsule to the base : capsule cylindrical-oblong, papillose, grad- 

 ually narrowed to a short pedicel ; lid convex, enlarged at base, 

 abruptly short-beaked. — Prod. 84 ; Sulliv. Mosses of TJ. States, 

 41, and Icon. Muse. 75, t, 47. Polytrichum Pennsylvanicum, 



