Japan Flora: Rhizomes long-creeping; culms 3-30 cm. long, smooth; basd leaf-sheaths with blades, somewhat purplish, the upper leaf-blades 1-2 mm. wide, smooth, soft, slightly involute; terminal spike staminate, linear, 5-20 mm, long, the lateral 1 to 3, pistillate, erect, approximate, oblong, 5-15 mm. long, sessile, rather loosely 7- to 15-flowered, the lower 1 or 2 bracts leaflike, involute; pistillate scales ovate, dark purplish brown, obtuse; perigynia longer than the scales, suberect, ovate, 3.5-4 mm. long, thick, planoconvex, glaucous-green, nerveless, thick, densely papillose, abruptly very short-beaked with a rather firm entire tip; stigmas 2. June-July. Salt marshes.

Hokkaido. Kamchatka, Kuriles, Sakhalin, and circumpolar areas.