Japan Flora: Slender, glabrescent perennial; culms 30- 50 cm, smooth; leaves flat, 3-5 mm. wide, long-attenuate, the sheaths broadly winged on the angle; partial panicles 4-6, distant, erect, 1.5-3 cm. long, the branches smooth, suberect; spikelets 4-5 mm. long; achenes nearly globose, whitish with indistinct brown flecks, lustrous, 2 mm. across, glabrous or slightly puberulent, with elevated reticulations; hypogynium appressed, the lobes ovate-deltoid, abruptly contracted at apex, with a projection on the center. July-Oct Wet places.

Honshu, Shikoku, Kyushu; rather common. Korea, China, India to Africa.