Annual. Stems tufted, 4–16 in. long, rather slender. Leaves few, 1/2– 3/4 the length of the stem, 1/12– 1/8 in. broad, weak. Umbel simple (sometimes 1 spike only present); rays 2–5, 0–2 1/2 in. long; bracts 3, lowest 3–7 in. long, similar to the leaves. Spikes of 2–5 nearly sessile spikelets, ebracteolate. Spikelets up to 1/2 by nearly 1/5 in., turgid, moderately compressed, linear-oblong with parallel sides, 8–18-flowered, glistening-white purple-marked; rhachilla persistent, not winged. Glumes ovate, obtuse, 7-nerved, closely imbricated, rounded or scarcely keeled on the back, caducous regularly beginning with the lowest nut-bearing one. Style 2-fid or more rarely 3-fid. Nut 2/5 the length of the glume, obovoid, flattened on the anterior angle, usually so much flattened that the nut is biconvex and the anterior style-branch gone, sometimes unequal trigonous with 3 style-branches.
