Culms often curved, weak, 10-25 cm. Leaves ± gray-green, often channeled, rarely flat, 1-2 mm wide. Inflorescences 7-25 × 5-12 mm. Pistillate scales 2-3 mm, rarely enveloping perigynia. Perigynia lightly or obscurely several-veined on faces, 1.5-3.5 × 1-1.5 mm.

Fruiting Jun-Aug.. Salt marshes, gravelly seashores; 0-100 m; Greenland; B.C., Man., N.B., Nfld. and Labr., N.W.T., Nunavut, Ont., P.E.I., Que., Yukon; Alaska; Europe.

G. Halliday and A. O. Chater (1969) recognized two well-defined varieties in the subspecies: var. glareosa and var. amphigena. Variety amphigena, which is the overwhelmingly dominating type in North America, has pale brown to whitish, broadly elliptic-obovate perigynia (1.5-2.5 × 1.3-1.5 mm) contracting abruptly into a minute beak. Variety glareosa often has lanceolate, light brown to whitish, and sometimes distinctly ribbed perigynia more than 2.6 times as long as wide and 2.5-3.5 × 1-1.5 mm in size. According to G. Halliday and A. O. Chater (1969), it is an amphi-Atlantic plant. It occurs in Greenland and a few places in eastern Canada, and it is relatively common in Fennoscandia (Finland and Scandinavia) and northwestern Russia. In many places it grades to the var. amphigena.