Annual or perennial herbs, usually with brittle stem and watery juice, erect or staggering, mostly glabrous. Leaves usually alternate, rarely opposite, pinnately divided without jointed segments; leaflets small, thin, more or less lobed; stipules absent. Inflorescence a raceme, spike or corymb, rarely 1-3-flowered, terminal, usually zygomorphic, hypogynous, bracteate, pedicellate. Sepals 2, small, scale-like, caducous. Petals 4, erect, in 2 dissimilar whorls; 2 outer longer and larger, one or both spurred or saccate and often coherent at tips. Stamens 2 (apparently 6 in 2 bundles), tripartite, the central branch bearing a bithecous anther, the lateral branches bearing monothecous anthers. Ovary 1-locular with 2 parietal placentas, each bearing 1-many anatropous ovules; style simple, filiform, long or short; stigma obtuse or bilobed. Fruit a 2-valved capsule or a nutlet. Seeds small, black.
14 genera, 400 species