Plants annual. Culms to 60 cm, procumbent to erect, sparingly branched at the base. Leaves basal and cauline; sheaths open, glabrous; auricles absent; ligules longer than wide, acute; blades linear, usually flat, sometimes convolute when dry, glabrous. Inflorescences terminal, racemes or panicles, usually with 1 branch per node; branches stiff, 3-sided. Spikelets lanceolate to ovate, laterally compressed, with 4-25 florets, distal florets reduced; disarticulation above the glumes and below the florets; rachillas not prolonged beyond the uppermost floret. Glumes unequal to subequal, shorter than the spikelets, 1-5-veined; calluses blunt, rounded, glabrous; lemmas narrowly elliptic, coriaceous at maturity, inconspicuously 5-veined, glabrous, sometimes scabridulous towards the apices, apices acute, sometimes bifid, often mucronate; paleas about as long as the lemmas, 2-veined; lodicules 2, free, lanceolate; anthers 3, only slightly exserted at anthesis; ovaries glabrous. Caryopses ellipsoid-oblong, dorsally flattened, falling with the paleas; hila about 1/10 as long as the caryopses, ovate. x = 7. Named for Jean Baptiste Henri Joseph Desmazières (1786-1862), a French merchant, amateur botanist, and horticulturalist.