Japan Flora: Rhizomes short; culms 80-120 cm. long, stout, with 4 or 5 nodes; radical leaves linear, the cauline 3-4 mm. wide, gradu­ally attenuate; partial panicles 4-6, the lateral composed of 1 or 2 clusters of spikelets, the terminal with 3-6 stiffly erect simple rays, the bracts leaflike, narrow; spikelets sessile, ob­long, 5-7 mm. long, 2.5-3 mm. thick, dark grayish brown when mature, in globose-capitate clusters of 10-20 spikelets; scales ovate-deltoid, 2.5-3 mm. long, 1-1.2 mm. wide, acute; achenes obovate, mucronate, compressed-tiigonous, about 1 mm. long, pale, the bristles 6, flexuous, about 5 mm. long, sparsely ascending-spinulose at tip. Aug.-Oct. Swamps.

Honshu, Kyushu.

Japan Flora: Differs from the following in the lateral branches of the panicle with 5-10 clusters of spikelets, the terminal panicle decompound, and by the more slender rays.Aug.-Oct. Swamps.

Honshu (Shinano Prov., Karui- zawa); rare. Korea and Manchuria.