Plants green to yellowish-brown or pale brown. Leaf cells 18--24 ´ 21--28 m m in midleaf, trigones distinct but never bulging, oil bodies 2--10 per cell.

Wet humus over boulders, shaded cliffs, soil over exposed rock surface, decaying branches at the fringes of spray zones, and among heather on slopes; 0--1240 m; e, nw and sw Greenland; Alta., B.C., Man., N.B., Nfld. (Labrador), N.W.T., N.S., Nun., Ont., Que., Sask., Yukon; Alaska, Colo., Conn., Maine, Mich., Minn., Mont., N.H., N.Y., Oreg., Vt., Wash., Wis.; Europe; Asia.

This subspecies is frequently associated with Anastrophyllum minutum, Barbilophozia attenuata, B. barbata, Tetralophozia setiformis, Diplophyllum taxifolium, Geocalyx graveolens, Gymnomitrion coralloides, Leiocolpos heterocolpos, Lophozia sudetica, Mylia taylori, Odontoschisma macounii, Plagiochila asplenioides, Ptilidium ciliare, Scapania americana, S. mucronata, and S. nemorosa.