BARNES— NORTH AMERICAN MOSSES. 275 



ulate or subacute, borders re volute but flat below point; costa stout, rufes- 

 cent when old, vanishing at or below apex; cells small, distinct, thick- 

 walled, irregular, roundish quadrate, minutely papillose, lower rectangu- 

 lar, rather elongated towards costa, quadrate or transversely dilated on 

 borders: perichsetial leaves not sheathing, oblong-lingulate, obtuse at apex: 

 seta reddish, twisted to left above: capsule erect, cylindrical, badious when 

 old, lid obliquely rostrate; peristome unknown. Bot. Gaz. 15: 40. 1890. — 

 Crevices of rocks: Oregon. 



115. Didymodon rxifiis Lorentz. — Dioicous: tufts compact or loose, 

 dark reddish brown, brownish green above: stems 2-4 cm. high, erect or 

 geniculate, forked or fasciculately branched: leaves crowded, spreading 

 and recurved above middle, when dry erect appressed or slightly twisted, 

 gradually acuminate from an ovate lanceolate base, margin entire, revolute 

 on border; costa percurrent or vanishing below apex, round, rough on both 

 sides; lamina of one layer of cells, long mamillose-papillose; cells equally 

 and strongly thickened, lumen round or transversely oval, at base near 

 costa elongated rectangular, faintly pitted, and several marginal rows 

 quadrate: fruit unknown. Limpr. Laubm. 1: 559. — Greenland. 



116. Leptodontiuui Hampe. — Leaves squarrose-reflexed, complicate- 

 concave, flexuous, the margin serrulate or erose-crenulate: capsule lepto- 

 dermous, narrow, erect; lid conic; peristome of 32 filiform straight erect 

 smooth teeth, unequal or anastomosing here and there in pairs, or connas- 

 cent; calyptra cucullate. 



117. Leptodoutium Canadense Kindb. — Tufts loosely cohering, nearly 

 without rhizoids, dark green, blackish below: stem about 1 cm. high, 

 nearly simple: leaves squarrose, fl.exuose, undulate and not recurved at 

 borders, when dry curled, sublingulate, acute, entire below middle, coarsely 

 and unequally serrate above, not margined; lower basal cells rectangular 

 and subpellucid, upper at middle quadrate, uppermost rotundate, slightly 

 papillose; costa finally brown, short excurrent: dioicous, only female plants 

 found. Mac. Cat. 45. — On stones: in the Sydenham river, Owen Sound, 

 Ont. 



118. Tricliostumum nitidum Schimp. — Dioicous: tufts compact, pulvi- 

 nate, 1-1.5 cm. high, olive-green, within reddish brown and radiculose: 

 stems rigid and dense-leaved: leaves accrescent upwards, fragile, spread- 

 ing when moist, when dry arcuate-incurved, with faintly crenulate in- 

 curved margins, glossy shining on the back, linear lanceolate, mostly ob- 

 tuse, short pointed by excurrent costa; hyaline leaf base forming ^ leaf, 

 hyaline cells continued upwards as a border, but less sharply marked off 

 from chlorophyllose cells, latter round-quadrate, with simple or gemi- 

 nate papillae on both sides: perichaetial leaves half sheathing, gradually 

 diminishing in size, almost subulate: capsule erect, nearly cylindric, faintly 

 curved, when old somewhat furrowed; lid ]/3 capsule, obliquely rostrate; 



