632 MUSCI. (MOSSES.) 



costate, plane on the margins ; areolse above guttulate ; below, enlarged oblong. 

 (Name from vyos, a pair, and ofiwi/, teeth, in allusion to the paired teeth.} 



1. Z. Lapp6nicus, Br. & Sch. Stems '-l'high, radiculose; leaves 

 spreading, crisped when dry; capsule scarcely exserted, 8-ribbed; peristome 

 none : monoecious ; male flower gemmiform. Rocks, on the White Mountains 

 of New Hampshire, Oakes: Allcghany Mountains of Pennsylvania, Lesyuereux. 

 (Tah. 16.) (Eu.) 



2. Z. IVIougcotii, Br. Sch. More elongated and branched than No. 

 1 ; differing chiefly in its narrower and less concave perichaetial leaves twice as 

 long, the longer rostrum to the operculum, and the dioecious inflorescence. 

 With No. 1, in similar places, according to Mr. Th. P. James. (Eu.) 



3. Z. Slllliv until, Mull. Stems l'-2' high, slender, with long filiform 

 branches ; leaves subsquarrose from an erect half-clasping base, complicate-con- 

 cave ; the margins below recurved, above plane and strongly serrate ; fruit 

 unknown. (Syrrhopodon excelsus, Sulliv. Muse. Alleghan., No. 170.) North 

 Carolina; on rocks, top of Grandfather Mountain, Gray $ Sulliuant: Black 

 Mountain, Lesquereux. 



31. DRUJTUHONDIA, Hook. (Tab. 16.) 



Calyptra large, cuculliform, rostrate, slightly plicate at the base, and papillose 

 at the apex. Operculum obliquely long-rostrate from a convex base. Capsule 

 globose-oval or slightly obovate, exsertly pedicellate. Peristome single : teeth 

 16, very short, truncate. Inflorescence dioecious: male flower gemmiform. 

 Perennial, growing on trees ; stems prostrate, throwing up numerous short 

 branches, bearing fruit on their summit; leaves oblong, costate; areolse minute, 

 roundish. (Named after the late Thomas Drummond, who made extensive and 

 very valuable collections of North American Mosses.) 



1. U. clavelliita, Hook. Stems 2'-4' long, creeping, densely covered 

 with radicels ; branches crowded, erect, 2" -3" high; leaves close, erect-patent, 

 shortly acuminate ; costa ceasing with the apex. Grows in deep-green and close 

 thin mats (3' -10' in diameter), on the bark of trees (particularly the Beech), 

 Northern, Middle, and Western States. (Tab. 16.) 



TRIBE XIII. ORTHOTRICHE^. 



32. ORTIIOTRICHUM, Hedw. (Tab. 16.; 



Calyptra large, campanulate, longitudinally plaited, crenate-lacerate at the 

 base, hairy or glabrous. Operculum short, conic, rostcllate. Capsule pyrifonn, 

 more or less elongated, apophysate, pedicellate, immersed or exserted, 8 or 16 

 striated, ribbed when dry. Peristome single or double, rarely wanting; the 

 outer 16 teeth, with a medial line, mostly in pairs (often reflexed when drv) ; 

 the inner 8 or 16 cilia. Inflorescence monoecious or dioecious: male flower 

 gemmiform. Perennial plants, growing in roundish cushion-like tufts, en trees 

 01 rocks, never on soil ; stems usually erect, simple or branched by innovations, 

 fertile at their summit; leaves crowded, elongated, restate nearly to the point, 



