Japan Flora: Rhizomes stout, creeping; culms stout, 30-80 cm. long, with 1 or 2 nodes; leaf-blades flat, soft, 8-15 mm. wide, prominently whitish beneath, the basal sheaths pale; spikes 3-6, erect, the terminal (rarely the upper 2) staminate, linear, 3-7 cm. long, pale yellow, the lateral pistillate, very densely many-flowered, cylindric, 2.5-5 cm. long, 7-9 mm. thick, nearly sessile, the bracts leaflike, longer than the culm, sheathless or the sheath extremely short; pistillate scales narrowly oblong, obtuse and short-awned, pale or light tawny; perigynia slightly longer than the scales, 4 mm. long, spreading, broadly obovoid, glabrous, inflated, light green, grayish brown when dried, wrinkled, slenderly many­nerved, the beak short, recurved, with a hyaline 2-toothed tip; stigmas 3.  May-Jnly. Wet muddy places in mountains.

Hokkaido, Honshu, Shikoku, Kyushu; rather abundant. India, Indochina, and Malaysia.