400 BRYACE^. [Hypnum. 



the middle, or simple and ascending to near the apex, yellow ; 

 basilar cells narrower than in If. niolle, yellowish, those of the 

 basal angles broadly rectangular or hexagonal, orange ; ijerichae- 

 tiuni erect, sheathing, with few solid sulcate entire leaves: cap- 

 sule incurved, cernuous, turgid, oblong, subarcuate, and con- 

 stricted under the orifice when dry and empty ; operculum 

 highly convex, obtusely papillate, orange; teeth short; seg- 

 ments subulate; annulus large, persistent. — Muse. Frond. 

 Suec. 63, excl. t. ; Hedw. Sp. Muse. 247, t. 64. // vtoUe, Brid. 

 Bryol. Univ. ii. 570, excl. syn. Limnohiwn alpestre^ Bruch & 

 Schiinp. Bryol. Eur. t. 577. 

 Hai!. North America, according to Aiistin. 



168. H. arcticum, Sommerf. Tufts loose, rigid, dark olive 

 green ; stems slender, horny, with few simple branches, naked 

 and rootless at base: leaves small, open, solid, round-ovate, 

 obtusely pointed, very entire, slightly inflated on the borders, 

 plano-concave, subcochleariform ; costa distinct, ascending to 

 below the apex, simple or bifurcate; areolation very narrow, 

 not dilated at the angles ; inner perichajtial leaves long-lanceo- 

 late, costate, scarcely sulcate: capsule small, suberect or cernu- 

 ous, oval, narrowed to a distinct collum, arcuate when dry; 

 operculum mammiform; segments entire; cilia two, short; 

 annulus double. — Wahl. Fl. Lajip. Suppl. 65, t. 2. Limnobium 

 arcticum, Bruch & Schimp. Bryol. Eur. t. 578. Stereodon 

 arctiois, Mitten, Journ. Linn. Soc. viii. 42. 



IIAI5. On rocks along rivulets near Closter, Xew Jersey [Aiistin)\ 

 Rocky Mountains (Drummond, Lyall). 



169. H. obtusifolium, Drumm. Loosely cespitose; the 

 branches more numerous, short and simple, thick, turgid and 

 subclavate, or longer and slightly ramulose: leaves loosely im- 

 bricate all around when dr.y, half-open when moist, broadly oval, 

 obtuse, very concave, slightly serrulate ; costa simjvle, ascending 

 to near the apex ; areolation very narrow, not enlarged at the 

 angles : pedicel rough, flexuous, arcuate below the largo oval- 

 oblong pendent or horizontal capsule, Avhich is not constricted 

 nnder the orifice when dry; operculum not seen ; peristome as 

 in IT. mone.— Mnsc. Amer. n. 193. II arcticum, var., Mucll. 

 Syn. ii. 432. Stereoclon obtusifoUus, Mitt. 1. c. 



Uav,. Ilivnlets in the Rocky Mountains (Bnnnmond) ; British Colum- 

 bia {L]/'ill); IMonnt Dana, California, sterile {liolnnder); Oregon, in fruit 

 {E. Hall), from whose specimens the diagnosis has been completed. 



