Japan Flora: Culms tufted, green, slender, 10-40 cm. long, obtusely 4- or 5-angled, naked; basal sheaths cylindrical, obliquely truncate at tip, blade less; inflorescence capitate, pseudolateral, dense, composed of 2-5 spikelets; bract 1, erect, 1-13 cm. long, continuous with the culm; spikelets narrowly ovoid, 3-17 nun. long, 3-35 mm. wide, acute, sessile, pale green; scales elliptic, 3.5-4 mm. long, obtuse; stigmas 2; achenes broadly obovate, about 2 mm. long, planoconvex, slightly rugose; bristles 4, much longer than the achene, retrorsely scabrous. Aug.-Oct. Swampy places.

Honshu, Shikoku, Kyushu. Korea, China, Formosa, and India.