Annual or perennial. Ligule membranous, short, or a ring of hairs. Leaf-blade flat to convolute. Inflorescence usually a contracted panicle, rarely a raceme, often secund. Spikelets pedicelled; disarticulation above glumes but not between florets; rachilla not prolonged. Glumes equal or unequal, usually ≤ spikelet and becoming widely reflexed. Lemmas of Ø florets usually unequal, glabrous or hairy, one or both often transversely rugose, awned or awnless; lower lemma ≤ glumes, upper usually > glumes, boat-shaped, frequently with basal appendages or tufts of hairs. Lemma of ☿ floret usually shorter, awned or awnless, very often with a knob-like appendage at base forming a hinge with the appendage of the upper Ø lemma. Palea ≈ lemma of ☿ floret, narrowly 2-nerved. Lodicules cuneate, finely nerved below. Stamens 6 or 3. Stigma branches aspergilliform. Caryopsis elliptic; embryo ¼-⅕ length of caryopsis; hilum ≈ caryopsis.