366 BULLETIN OF THE UNIVERSITY OF WISCONSIN. 



cells usually sinuous, somewhat pitted. Ren. in Husn. Muscol. Gall. 394. 

 1894. Miquelon Is. 



600. Hypnum incurvatum Schrad. Stem 2-4 cm., delicate, creeping, 

 irregularly branching; tufts small, depressed, silky, green or slightly yel- 

 lowish: leaves erect spreading, sub -secund, more or less arcuate, oblong - 

 lanceolate, long-acuminate, entire or distantly toothed at apex; costa none 

 or very short and faint, or bifurcate; cells of angles quadrate, middle cells 

 short, 6-8 times as long as wide: monoicous: two inner perichsetial leaves 

 sheathing, abruptly and narrowly acuminate, superficially denticulate at 

 summit, not plicate, faintly costate: capsule horizontal, sometimes oblique, 

 oblong or almost cylindric, arcuate, contracted below mouth; lid conic, 

 short rostrate; annulus large. Husnot, Muse. Gall. 399. Newfoundland. 



601. Hypnum dilatatum Wils. Stems 2-10 cm., prostrate, ascending, 

 long denudate at base; tufts depressed, rather rigid: leaves sub-secund or 

 secund, concave, sub-orbicular, obtuse or shortly and obtusely apiculate, 

 narrowed at base, slightly denticulate at apex; costa bifurcate, very short 

 or scarcely ^| the leaf; cells of basilar angles large, hexagonal-rectangular, 

 usually orange, forming rather disinct auricles, the rest longer than in H. 

 molle: inner perichsetial leaves sheathing, plicate: monoicous: capsule ob- 

 lique or horizontal, oblong; operculum convex-conic. Husn. Muscol. Gall. 

 413. If. molle Br. & Sch., not Dicks. Greenland; Canada; Rocky Mts.; 

 British Columbia; Idaho; Eastern States. 



602. Hylocomium squarrosum calrescens (Wils.) Husnot. Plants a 

 little more robust, branches more numerous: stem leaves larger above, 

 more distinctly denticulate, slightly plicate; leaf cells, pedicel and capsule 

 similar to type. Husnot, Muse. Gall. 425. H. calvescens Wils. On rocks: 

 Nova Scotia; British Columbia. 



603. Hylocomium triquetrum Californicum Ren. & Card. Very ro- 

 bust: leaves strongly rugose undulate, strongly papillose above: capsule 

 short. Bot. Gaz. 15: 61. 1890. California. 



