Mostly annual herbs, rarely perennials or shrubs; stems often 5-angled, prostrate or climbing by means of tendrils. Leaves alternate, petiolate, simple and then often palmately-lobed and with a cordate base or palmately compound with the lateral leaflets asymmetrical. Stipules wanting. Tendrils arising beside the petiole, sometimes with a joint, branched or simple, usually coiling in the upper part. Inflorescence consisting of axillary cymes, racemes or panicles, or flowers solitary. Flowers usually unisexual, rarely hermaphrodite, actinomorphic. Receptacle bell-shaped or tubular. Sepals 5, imbricate, free or basally connate. Petals 5, inserted on the rim of the receptacle, free or united, the lobes valvate. Stamens 3, free or variously united; filaments free; anthers free, cohering or confluent into a head, two of them 2-celled, the other one 1-celled. Ovary inferior, or nearly so, (1—2)—3—(4—6)-celled; style short; stigma 3 cleft or 3 lobed. Ovules numerous to 1, placentas parietal. Fruit a berry. Seeds many. Embryo straight; cotyledons large. Endosperm wanting. About 850 species in 100 genera of tropical and subtropical distribution; a few species in temperate regions.