158 A MANUAL OF MOSSES 



Distributed over the whole earth, most abundant in damp 

 woods and swamps, on earth, bark of trees, or rocks, in the 

 temperate zones. Five genera, of which but one occurs in our 

 region. 



I. MNIUM Linnaeus, Hedwig. 



Synoicous or dioicous, rarely autoicous: mostly robust, 

 cespitose in bright green to dark green or later brownish tufts ; 

 stem erect, often stoloniferous, often bearing creeping flagelli- 

 form branches ; leaves bract-like and remote below, increasing 

 upwards to the terminal rosette, broadly ovate, obovate, or 

 oblong, to spatulate from a narrow decurrent base, when dry 

 contorted to crispate, when wet erect-spreading to recurved, 

 mostly with a border of 1-3 layers of elongate prosenchy- 

 matous colored cells, each layer of the border usually sharply 

 serrate; costa stout; cells rounded to hexagonal, often col- 

 lenchymatous and punctate, uniform or smaller towards the 

 margin: seta single or clustered, long; capsule cernuous to 

 pendent, rarely erect, mostly oblong-ovoid, rarely arcuate; 

 exothecial cells rounded, annulus revoluble ; teeth strong, sepa- 

 rate at base, greenish-yellow to reddish-brown, more or less 

 papillose, the zigzag divisural line distinct, the dorsal plates 

 low, the trabeculae numerous, often united by sporadic cross- 

 walls ; inner peristome mostly yellowish-red, the basal mem- 

 brane half-way to the apex and sometimes perforate; seg- 

 ments usually as long as the teeth, lanceolate, mostly abrupt- 

 ly subulate, usually fenestrate and finally gaping; cilia com- 

 plete, mostly articulate ; spores .016-.048 mm. ; operculum con- 

 vex to conic and rostrate ; calyptra narrowly cucullate. 



About 90 species, cosmopolitan, on various sub-strata, 

 usually in moist or shaded situations ; 32 species occurring in 

 North America, about 11 species in our range. 



Key to the Species. 



a. Leaves not distinctly bordered. b. 



a. Leaves distinctly bordered. c. 



b. Margin with a single series of low irregular teeth in the upper 



half; cells incrassate. 9. M. stellare. 



b. Margin not distinctly toothed; cells thin-walled. 



11. M. cinclidioidcs. 

 c. Leaves with entire or almost entire margin. 



d. 

 c. Leaves with serrate margin. g. 



d. Border indistinct and of one series of cells only. 



11. M. cinclidioides. 

 d. Border of 2-4 series of cells in several layers. 



e. 

 e. Lid acutely rostrate; leaves obovate. f. 



e. Lid conic-apiculate; oblong to oval or sub-orbicular. 



8. M. afUne var. nig- 

 icmn. 

 f. On stones; leaves usually minutely apiculate and percurrently 



