Japan Flora: Rhi­zomes short; culms loosely tufted, 20-40 cm. long; leaf-blades 1-3 mm. wide, soft, flat, glaucous-green, densely papillose; spikes 3-5，mostly gynecandrous, contiguous or the lower ones more distant, the terminal sometimes staminate, usually clavate, the pistillate oblong, 7-12(-15) mm. long; pistillate scales ovate-orbicular, very obtuse, ferrugineous; perigynia as large as the scales, oval, 3 mm. long, at first glaucous, becom­ing glaucous-brown at maturity, faintly nerved, the margins obtuse and nearly smooth, the beak very short with an entire tip; achenes tightly invested by the perigynium; stigmas 2. June-July. Salt marshes near seashores;

Hokkaido (Nemuro); rare, locally  abundant. Sakhalin, n. Siberia, n. Europe, and Canada.