|Abstract||Dioecious trees (or tall herbs), often lepidote or hairy. Leaves large, simple, entire or dentate, spirally arranged, palminerved (or compound), often asymmetric. Stipules 0. Flowers actinomorphic, valvate, unisexual, rarely polygamous, in elongate, bracteate, caducous spikes or panicles.—♂ Flowers: sepals 4-9, free and very unequal or connate in a lobed tube, isomerous, in ♂ Tetrameles with a few occasionally additional lobules. Petals free, isomerous or 0. Stamens isomerous and episepalous, filaments often long; anthers basifix, intrors or latrors, incurved in bud. Rudimentary ovary present or 0.—♀ Flowers: sepals connate above the ovary or free. Petals and rudimentary stamens 0. Styles isomerous, opposite the calyx lobes, mostly inserted on the margin of the calyx, (2-fid, filiform), club-shaped, or with a capitate stigma. Ovary inferior, 1-celled, with 3-8 parietal, alternisepalous placentas. Ovules ~. Capsule opening at the apex with slits or splitting laterally; pericarp membranous. Seeds ~, very small, ovate or spindleshaped; testa punctate or scrobiculate, outer sheet loosely covering the embryo. Albumen 0. Embryo straight, cylindric.|
Distr. Three genera with 4 spp., Datisca (herbaceous) with one sp. in Asia and one in W. Central America, Tetrameles and Octomeles both with one Indomalaysian sp..