Japan Flora: Rhizomes elongate-creeping; culms solitary, erect, rather soft, 7-30 cm. long; leaves soft, 2-3 mm. wide; head solitary (very rarely 2 or 3), globose or ovoid-globose, sessile, 5-10 mm. long, pale green; bracts 3, leaflike, elongate; spikelets numerous, jointed at base, densely disposed, broadly lanceolate, 3-3.5 mm. long, compressed, 1-flowered, acute; scales membranous, pale green or with reddish brown flecks, the keel spinulose or sometimes smooth, the apex prolonged to a slightly recurved mucro; achenes half as long as the scale, obovate, brownish, laterally compressed; stigmas 2. July-Oct. Honshu, Shikoku, Kyu­shu. Ryukyus, Formosa, China, and other warmer regions.

var. leiolepis (Fr. & Sav.) T. Koyama. Spikelets slightly broader than in the typical phase, oblong, distinctly turgid, rather obtuse, lustrous, the keel of scale smooth, the mucro not re­curved. July-Oct. Hokkaido, Honshu, Shikoku, Kyushu. Korea and China.