20 



Stems v/ith leaves; always some shade of green, never gray. 



Leaves usually arranged in two opposite rows; rounded, lobed or 

 cleft, often curved under at the tips, usually dark green, mid- 

 rib absent; under or back side of the stem, towards which the 

 leaves curl, sometimes bearing what appear to be rootlets. . . . 



Leafy Hepat.'cs — Jungermanniales (Scale Mosses). 

 Leaves usually arranged equally around the stem (in Fissidens in 

 only two rows); sometimes flattened on two opposite sides of 

 the stem, never lobed or cleft, and when rounded not curved 

 under at the tips, varying from light to dark green, midrib 



present or absent True Mosses. 



Plants usually growing in bogs or very wet places; stems erect, 

 much branched, branches at tip of stems forming a thick 

 head; leaves usually light green, or tinged with red. . . . 



Sphagnum, or Peat Moss. 

 Plants growing on rocks in mountainous regions; stems erect, 

 short and inconspicuous; leaves very dark, almost black. 



Andreaea. 



Plants growing in all sorts of places; on wet or dry ground, 

 rocks, trees, decaying wood, and in streams or ponds. 



Stems usually erect and not branched; if slightly branched 

 by forking, usually with not more than two or three 

 branches; fruit at the end of the stem or a well developed 

 branch, sometimes appearing lateral by new growth of 

 the plant Acrocarpous Mosses. 



Stems prostrate or ascending, rarely erect, usually much 

 branched (i. e., with more than two or three branches); 

 fruit on the side of the stem or on a very short lateral 

 branch Pleurocarpous Mosses. 



B. Helps to Identify the Genera 

 of the more common and conspicuous mosses, without a lens. 



L Acrocarpous Mosses 



Manner of growth. — Individual plants of the acrocarpous mosses can nearly 

 always be easily separated, as the stems are erect and do not interweave. In some 

 cases the stems are matted together below with a felt-like mass of radicles called 

 tomentum. The stems of most acrocarpous mosses are usually unbranched, but 

 sometimes they fork with only two or three branches. 



Stems ascending to erect, usually much branched by forking; plants growing 

 on rock, leaves olive to dark green, except at the growing tip of the stem, 



which is lighter Grimmia, Rhacomitrium. 



Stems erect, not branched or with branches whorled at tip of stem; plants 

 growing on wet ground or on rocks, especially where water is dripping; 

 leaves usually light or yellowish green Philonotis. 



