Ditrichum Moss

Ditrichum heteromallum (Hedw.) E. G. Britton
Weisia heleromalla Hedw. Descr. 1: 22. 1787.
Didymodon homomallus Hedw. Sp. Muse. 105. 1801.
Trichoslomum homomallum Bruch & Schimp. in B.S.G. Bryol. Eur. (18-20:) Trichost. 16. 1843.
Ditrichum homomallum Hampe. Flora 50: 182. 1867.
Trichoslomum heteromallum Lindb.; Aust. Bull. Torrey Club 6: 74. 1876.
Plants gregarious or rarely cespitose; stems usually simple, only 5-10 mm. high, rarely branching and taller, 4-5 cm. high, with red tomentum: leaves spreading, twisted or secund when dry, 1-2 mm., rarely 3 mm. long, the apex subulate from a short ovate base; margins entire or rarely subserrulate at the apex, not revolute; costa broad, flat, not channelled, excurrent into the long slender awn, toothed at the apex; lower cells narrow, linear, not much thickened, the upper ones rectangular; perichaetial leaves clasping at the base, abruptly longsubulate. Dioicous: seta 1-2.5 cm. long, dark-red; capsule also dark-red, erect, cylindric, becoming ovoid, 1-1.5 mm. long; walls with small irregular hexagonal cells; lid small, conic, blunt, the cells straight, small, hexagonal,' the border dentate; annulus large, double, of two rows of cells, falling in fragments; mouth small, bordered by darker flaring cells; peristome long and slender, fugacious, with a short basal membrane; teeth bifid to the base or united below at the joints, rarely not divided, red or brown, smooth or slightly roughened: spores yellow, smooth, 12-14 ^ in diameter, maturing in fall and winter.
Type locality: Saxony, Germany.
Distribution: Rare in mountain regions of North America from the west side of the Rocky Mountains to Alaska; leported from the White Mountains, New Hampshire; also in Europe.