Bolander's Orthotrichum Moss

Orthotrichum bolanderi Still. Ic. Muse
Suppl. 64. 1874.
Plants almost black throughout, reaching 3.5 cm. in length, more or less branched above; leaves closely appressed-imbricate when dry, lanceolate, often ovate at the base, ± 3 mm. long, broadly keeled, when moist plane in the upper half and almost opaque owing to a double layer of rounded, incrassate, papillose cells 7-10 u in diameter, the margins narrowly reflexed when dry; costa stout, vanishing in the apex; median basal leaf -cells rectangular, 2-4 times as long as broad, the marginal shorter; autoicous; seta about 1 mm. long; capsules emergent, more or less 8-ribbed when dry and empty, oblong-ovoid, the neck about 2 mm. long; calyptra hairy; stomata superficial; annulus present; operculum conic-apiculate ; peristome-teeth 16, united in pairs, strongly papillose, the segments linear, nearly as long as the teeth, of two rows of cells, somewhat papillose; spores ± 20 u in diameter, maturing in early spring.
Type locality: On rocks, California. Distribution: On rocks; southern California.