Japan Flora: Rhizomes loosely tufted, bearing stout, elongate stolons; culms 30-60 cm. tall; leaves with flat, stiff, elongate blades 4-5 mm. wide, the basal sheaths pale-stramineous; spikes 5-7, erect, densely ar­ranged, the terminal one staminate, linear-cylindric, 4-8 cm. long, pale to pale-stramineous, the lateral spikes pistillate, nar­rowly cylindric, densely many-flowered, 4-10 cm. long, sessile, the lower ones short-peduncled, the lower 1 or 2 bracts leaflike, sheathless; pistillate scales lanceolate, long-awned, pale; peri­gynia longer than the scales, 3-3.5 mm. long, obliquely spreading, obovoid, pale yellowish green, membran이is, few­nerved, Insterless, scabrous, abrupdy contracted into a long recurved beak with a hyaline obscurely 2-toothed tip; stigmas 3, slender, deciduous. July-Sept. Swampy places along streams in low mountains.

Honshu (Yamato Prov. and w. Chugoku Distr.), Shikoku, Kyushu. Ryukyus, China, and Indochina.