Jennings: Manual of Mosses — 25. Climaceae 181 



10 cm, leafless below, bearing at the summit numerous erect-spreading, flexuous, 

 usually straight branches; leaves large; stem-leaves broadly amplexicaul, with a 

 more or less rounded and cucullate or apiculate apex; branch-leaves imbricated, 

 giving to the branches a thick and turgid appearance, about 2 x 0.7 mm, lance- 

 oblong to lingulate-oblong, denticulate at base but quite sharply serrate above, 

 plicate, somewhat cordate but little auriculate at the base; costa nearly reaching 

 apex; median leaf-cells about 6-10:1, linear-rhomboidal to linear-hexagonal, 

 shorter and wider towards the apex and towards the base, the alar somewhat 

 lax, wider, hyaline, few, forming small auricles; perichaetial leaves entire, non- 

 plicate, the inner sheathing: seta deep red, about 2.5-3 cm long; capsule erect, 

 castaneous, oblong-cylindric, about 4 mm long, about 3-4:1; lid often remaining 

 attached to the columella, straight, acutely rostrate; calyptra reaching to below 

 the capsule; peristome large, the teeth forming a cone when moist but usually 

 curved in between the segments when dry; spores mature in fall, green in color. 

 On wet ground in marshes, at borders of streams, margins of swamps and 

 lakes, etc.; Europe, Asia, and from Arctic America south to New Jersey and 

 the Northwest. It may eventually be found to occur in the northern part 

 of our region. 



2. Climacium americanum Bridel 

 American Tree Moss 



Plate XXXV 



Loosely cespitose, robust, yellowish-green, lustrous: primary stems creeping 

 stolon-like in the leaf-mould, throwing up at intervals dendroidal secondary 

 stems to a height of 5-8 cm; secondary stems with large, scattering to closely 

 imbricate, ovate, scale-like leaves below, above bearing a closely tufted group 

 of branches; branches ascending, 1.5-2.5 cm long, terete, acute to obtuse; 

 branch-leaves 1.7-2.2 mm long, about two-fifths as wide, broadly lanceolate, 

 sharply serrate in upper half, often denticulate below, acute, broadly auriculate, 

 erect-spreading, when dry imbricate, strong bi-sulcate; costa strong, ending just 

 below apex; median leaf-cells oblong-hexagonal with more or less rounded or 

 truncate ends, 5-7:1, rather incrassate, those of the auricles quadrate along the 

 margin to diamond-shaped towards the interior, the apical and the upper 

 marginal larger and rhombic-oblong: seta erect, stout, dextrorse above, sinis- 

 trorse below, castaneous, about 1-1.6 cm long; capsule castaneous, narrowly 

 cylindric, about 5-6 mm long, 5-6:1, erect to slightly curved, slightly con- 

 tracted below the mouth when dry, nearly smooth; annulus none; operculum 

 conic-rostrate, about 1 mm long; peristome-teeth shallowly inserted, orange- 

 castaneous, non-striate but decidedly papillose, strongly and rather densely 

 trabeculate, the lamellae and divisural not very distinct, the teeth slender and 

 often perforate below; segments usually longer than teeth, linear, arising from 

 a very narrow and often somewhat perforate basal membrane which is usually 

 inserted entirely below the rim of the urn, the segments yellowish, granular- 

 papillose, perforate-cleft in a ladder-like manner along the median line; cilia 

 none, or sometimes represented by mere stubs rising from the basal membrane; 

 exothecial cells heavily incrassate, castaneous-pellucid, oblong, the upper 

 rounded-quadrate, those at the rim smaller and transversely oblong, darkly 



