Plants in dense, soft, silky, green to yellow-brown mats; pseudoparaphyllia none. Leaves erect-spreading or sometimes + secund, 1.17--1.3(--0.5) mm, not or somewhat narrowed to the insertion, serrulate all around, especially at the insertion; distal cells 3--4:1, shortly oblong-rhomboidal; alar cells subqudadrate in small and inconspicuous groups of 3--7 cells along the margins. Specialized asexual reproduction by axillary obcuneate propagula. Sexual condition dioicous. Perichaetial leaves ciliate-dentate above. Seta 6--11 mm. Capsule erect and symmetric or nearly so, 0.5--1 mm, oblong-cylindric, contracted below the mouth and at the short neck when dry; annulus of 2 layers of cells; operculum convex-conic, stoutly mammillate to + rostellate; stomata in the neck; peristome teeth yellow; cilia of endostome 1--2, rudimentary to well developed. Spores 11--13 µm.

Rocks in damp, sheltered places, crevices of cliffs or under rock ledges, peaty soil or humus under overhanging turf, hollows under roots of trees, lower sides of logs, perhaps limited to calcareous habitats; low to high elevations; Greenland; Alta., B. C., N. B., Nfld. and Labrador, N.W.T., N.S., Nun., Ont., Que., Sask., Yukon; Alaska, Ariz., Calif., Colo., Idaho, Iowa, Mich., Mont., N.Mex., N.Y., N.Dak., Vt., Wash., Wyo.; Europe; Asia.

The leaves are serrulate all around---noticeably so at the insertion because of projecting pairs of cell ends---the distal laminal cells are elongate, and the alar cells are subquadrate in small, inconspicuous groups. The obcuneate brood bodies are highly distinctive, as are the dioicous inflorescence, the perichaetial leaves ciliate-dentate above, and the capsule erect and symmetric.