Japan Flora: Rhizomes thick, stout, long-creeping, forming a large mac; culms 30-100 cm. long, scabrous on the angles above; leaf-blades 3-8 mm. wide, flat, grayish green, somewhat glaucous, the basal leafs heaths partly reddish or reddish purple, reticulate-fibrous; upper 1 to 3 spikes staminate, 2-4 cm. long, the lower 2-4 pistillate, sometimes androgynous or partially staminate, cylindric, 2-6 cm. long, pendulous on long capillary peduncles, the lower 1 or 2 bracts leaf-like; pistillate seal效 lanceolate to ovate, purplish brown; perigynia shorter than the scales, elliptic, 3-3.5 mm. long, unequally biconvex, glaucous, obscurely nerved, rather firm, abruptly very short beaked, with an entire rip; stigmas 2. 

Abundant in wet places along seacoasts in Hokkaido, and in shallow ponds of subalpine regions in Honshu (Echigo, Rikuchu, and Ugo Prov.)  Sakhalin, Kuriles to Siberia and N. America.