Twining, rarely erect herbs, glabrous, rarely slightly pubescent. Leaves ovate, elliptic, oblong or lanceolate. Flowers in pedunculate umbelloid cymes. Calyx 5-partite, lobes linear to subulate, acute. Corolla white or greenish, generally striped or spotted with purple, glabrous outside, tubular, base inflated, lobes as long as the tube or smaller, connate at the tips. Corona double, attached to the staminal column, the outer series consisting of 5 truncate or bifid segments, the inner of 5 segments, longer than the staminal column. Staminal column very short, included in the basal part of the corolla, anthers without membranous appendages. Pollinia erect, solitary in each locule, with pelucid margin. Follicles linear-lanceolate, acuminate, smooth.