Leaf cells 18--22 ´ 20--35 m m in midleaf; gemmae irregularly polygonal to pyriform, rust-red, 15--25 ´ 12--20 m m.

Creek banks, decayed wood, and humus over decayed wood in forests; 0--2300 m; Greenland; Alta., B.C., Nfld., N.W.T., N.S., Nun., Ont., Que., Yukon; Alaska, Colo., Conn., Idaho, Iowa, Maine, Mass., Mich., Minn., Mont., N.H., N.Y., N.C., Pa., Vt., Wash., Wis., Wyo.; Europe; Asia.

In the East it is frequently associated with Bazzania trilobata, Lophozia ascendens, L. longidens, and Tritomaria exsecta. In the West it is associated with Blepharostoma trichophyllum, Cephalozia lunulifolia, Gymnomitrion coralloides, Lepidozia reptans, Lophozia incisa, L. ventricosa, and Ptilidium pulcherrimum.