Tall, evergreen woody climbers with opposite somewhat coriaceous leaves. Inflorescence a terminal cyme. Flowers large, white in the axils of foliaceous, caducous bracts. Calyx 5-segmented, glandular or eglandular inside; segments large, sometimes foliaceous. Corolla funnel shaped, or campanulate, white with short tube, lobes broad, overlapping to the right in bud. Stamens included at the summit of corolla tube; filament somewhat broadened at the top, with sagittate, horny anthers, united with the stigma. Disc deeply 5 lobed. Ovary bilocular with many ovules in each locule; style filiform; stigma fusiform. Follicles 2, connate, separating at maturity, woody. Seeds compressed, with a tuft of silky hairs.