Suffrutescent and herbaceous twining vines, unarmed, terrestrial, with raphides in the tissues, with foetid or disagreeable odor when tissues are bruised. Leaves opposite or occasionally 3-4-verticillate, petiolate, entire, with higher-order venation not lineolate, occasionally with pubescent domatia; stipules interpetiolar, triangular or bilobed, generally erect and valvate in bud, persistent or caducous. Inflorescences axillary and/or terminal on main stems or short lateraly stems, thyrsiform to spiciform or cymose, several--multiflowered, pedunculate to subsessile, bracts developed and sometimes enlarged, stipitate, and colored. Flowers sessile to pedicellate, bisexual, homostylous, apparently protandrous, perhaps fragrant and diurnal; hypanthia generally ellipsoid; calyx limb developed, (4)5(6)-lobed, occasionally with calycophylls; corolla salverform to funnelform with tube usually very slender then markedly enlarged at top, white to pink or purple, internally glabrous except pubescent in upper part and on lobes, sometimes fenestrate at base, lobes (4)5(6), triangular, induplicate-valvate in bud, sometimes with margins crisped, sometimes trifid at apex; stamens (4)5(6), inserted at various levels near middle of corolla tube, anthers ellipsoid to oblong, dorsifixed, opening by linear slits, without apical appendage, included; ovary 2(3)-locular, with ovules 1 in each locule, basal; stigmas 2(3), included or exserted. Fruits drupaceous often becoming schizocarpous, compressed-globose to compressed-ellipsoid, dry and usually shiny then fragmenting, with calyx limb persistent and sometimes becoming enlarged; pyrenes 2(3), 1-locular, oblong to ovate in outline and flattened, membranceous to coriaceous, indehiscent, sometimes marginally winged, sometimes borne on persistent carpophores; seeds 1 per pyrene, generally flattened.