Herbs, rarely shrubs or trees. Leaves alternate or opposite, simple. Stipules usually wanting, when present small and caducous. Flowers usually solitary in the leaf-axils or by reduction of the leaves apparently arranged in spikes or racemes, hermaphrodite, actinomorphic or zygomorphic. Receptacle cylindric, prismatic, obconical or funnel-shaped. Sepals 2—7, free, valvate, persistent or deciduous. Petals 2—7 or wanting, free, contorted or imbricate. Stamens as many as the petals or twice as many and then bi-seriate, rarely only 1 or 2; when bi-seriate the epipetalous smaller and sometimes sterile; filaments free, filiform; anthers linear or oblong, 2-celled, introrse, with longitudinal dehiscence. Disk epigynous. Ovary inferior, 2—7-locular; style simple, filiform to cylindric; stigma lobed or capitate. Ovules numerous, on axile placentas. Fruit a capsule, nut or berry. Seeds small, one to numerous. Embryo straight or nearly so. Endosperm wanting. About 500 species in 20 genera, cosmopolitan but mostly in temperate regions.