Japan Flora: Culms tufted, 40-60 cm. long, rather slender, scabrous above on the angles, few-leaved at purplish base; leaf-blades 2-4 mm. wide, slightly paler beneath, soft, scabrous on margin, the basal sheaths with blades, dark purplish, slightly lustrous, sparingly reticulate-fibrous; spikes 3 or 4, nodding, the ter­minal gynecandrous, clavate, the lateral pistillate, oblong to oblong-cylindric, 10-25 mm. long, on long setaceous peduncles, the lowest bract foliaceous, as long as or longer than the in­florescence; pistillate scales ovate, ascending, pale yellowish brown, membranous, acute and short-awned; perigynia nearly equaling the scales, ovoid, 3-3.5 mm. long, ascending, inflated- trigonous, pale green, membranous, slenderly nerved, short- beaked, the tip ferrugineous, acutely bi dentate; achenes loosely invested by the perigynium; stigmas 3, short, slender；July-Aug. Calcareous rocks in mountains.

Honshu (Mount Toyo- kuchi in Shinano Prov.); very rare, Korea and Manchuria.