Japan Flora: Culms 15-30 cm. long, soft but rather stout, scabrous, acutely angled; leaf-blades flat, soft, rather thin, bright green, 4-8 mm. wide, the basal sheaths pale; spikes 3-6, nearly contiguous, erect, sessile, the upper ones al­most fastigiate, the terminal staminate, linear, pale green, 1.5-3 cm. long, the lateral pistillate, short-cylindric, densely many­flowered, sessile or nearly so, 1.5-3 cm. long, the lowest one often somewhat distant and short-peduncled, the lowest bract leaflike, spreading or slightly deflexed, sheathless; pistillate scales narrowly ovate, long-acuminate, pale; perigynia longer than the scales, 3-4 mm. long, spreading or slightly reflexed, narrowly ovoid, inflated, trigonous, pale green, glabrous, few­nerved, gradually long-beaked, with a minutely 2-toothed hya­line tip; stigmas 3, short, slender. May-July. Damp woods in mountains;.

Hokkaido, Honshu, Shikoku, Kyushu; rather rare. s. Korea and s. Kuriles.