Japan Flora: Deep green perennial; rhizomes horizontally creeping, firm, the internodes slightly elongate or short; culms erect, distinctly compressed, 20-50 cm. tall, more or less twisted; the basal sheaths scalelike; inflorescence pseudolateral, the lowest bract having the appearance of a continuation of the culm, some­times longer than the inflorescence; flowers solitary, numerous, dense, 4-5 mm. long including the capsule; perianth-segments broadly lanceolate, acute, brownish green dorsdly, blackish brown on both margins, the inner slightly shorter than the outer; stamens 6, half as long as the perianth, the anthers lin­ear, 1.5 mm. long, the filaments very short; capsules oblong- ovoid, longer than the perianth, abruptly acute, dark brown; seeds obovoid, 0.8 mm. long. Wet sandy places, especially near seashores.

Hokkaido, Honshu (n. and centr. distr.).

var. laxus Satake. Inflorescence loose 도 capsules gradually narrowed above and terminated by a mu­cro; perianth-segments all equal in length. Kyushu.