glabrous, large or medium-sized; stolons 1/20 in. in diam., clothed by black-brown acute scales 1/3 in. long, but as in other stoloniferous species by no means always produced by the plant, rarely present in herbaria; stems 12–25 in. long, trigonous at the top, smooth, somewhat slender; leaves nearly as long as the stem, 1/5– 1/3 in. broad; umbel usually 4–8 in. in diam. compound (small examples with condensed umbel occur); bracts 3–6, overtopping the umbel, similar to the leaves; spikelets loosely spicate, compressed, pale or reddish, often 3/4 by 1/20– 1/12 in., very variable in breadth, and up to 1 3/4 in. in Rehmann, 7752, 10–20-flowered; rhachilla narrowly winged, the linear-lanceolate, scarious-white wings finally dehiscing from the base (exactly as in C. rotundus, fastigiatus, &c.); glumes distant, hardly boat-shaped, elliptic, obtuse, 3-nerved, green on the back; stamens 3; anthers linear-oblong, not crested; nut 1/2– 2/3 the length of the glume, trigonous, oblong or somewhat obovoid, brown; style much shorter than the nut, branches 3 linear, a little exserted from the glume. null