Fls 5-merous, large, ebracteate, axillary, solitary or in cymes. Outer calyx-lobes or sepals us. > inner, erect. Corolla us. broad-funnelform, limb sts angled or lobed. Staminal filaments filiform, sts dilated at base. Ovary us. 2-loculed, 4-ovuled. Style filiform, stigma capitate or with 2 globose lobes. Capsule us. subglobose, 4-valved. Seeds glab. or pubescent. Twining prostrate or scrambling herbs, often lianoid, with alt. variously cut lvs. A widespread, mostly maritime, genus of some 450 spp.

Herbs or less commonly shrubs, usually with twining or trailing stems. Latex present, often white. Lvs simple, mostly petiolate; lamina very variable, from entire to lobed and finely dissected. Fls mostly in axillary cymes which are occasionally paniculate, sometimes solitary; bracts variously developed, not concealing calyx. Sepals 5, very variable, persistent and often enlarged at fruiting. Corolla small to large, 5-lobed, usually actinomorphic, occasionally slightly zygomorphic, contorted in bud, usually funnelform or campanulate, sometimes salverform or tubular, variously coloured; lobes usually very shallow; mid-petaline bands well-defined. Stamens 5, inserted near base of corolla tube, included or rarely exserted. Ovary 2- or 4-locular; each loculus usually with 4 ovules; style filiform; stigma capitate or with 1-3 globose lobes. Capsule usually 4-celled, rarely 6-celled, usually 4-seeded. Seeds glabrous or hairy.