Japan Flora: Rhizomes very short; stems compressed, 2- winged, 20-40 cm. long, 2-3 mm. wide, usually 3-leaved; leaves all cauline, 10-20 cm. long, 3-5 mm. wide, linear-ensi­form, strongly compressed, pluritubulose，the septa inconspicu- ous; inflorescence a compound cyme of rather numerous globose heads, the lowest bract leaflike, short; flowers 5-6 mm. long including the capsule; perianth-segments linear, greenish, cuspidate, equal or the inner slightly longer than the outer; stamens 3, half as long as the perianth, the anthers oblong, shorter than the filaments; capsules linear-lanceolate to 3- angled-cylindric, cuspidate, much exceeding the perianth, thin; seeds obovoid, 0.6 mm. long.   Aug.-Sept Wet places.

Hokkaido, Honshu, Shikoku, Kyushu; common. Korea and China.