Japan Flora: acutely angled culms distinctly scabrous above; head solitary, 4-6 (-8) cm. long; pistillate scales ovate, membranous, chestnut-brown, 3-nerved, the green midrib ex­current into a needlelike smooth awn; perigynia longer than the scales, strongly divergent, many-nerved, conspicuously wing-margined, the wings dentate-serrate, the beak much longer chan in No. 15, and the tip more deeply bifid; achenes compressed-triangular; stigmas 3. May-July. Sandy places along seacoasts.

Hokkaido (except the sw. part). s. Kuriles, Sakhalin, Kamchatka, and w. coast of N. America.