Herbaceous tendrilled vines, or less often erect subshrubs, with woody base, not producing milky sap; stems furrowed, cylindrical or slightly angled; cross section with a single vascular cylinder. Leaves ternately or biternately compound, membranous or chartaceous; leaflets deeply serrate or lobed; petioles and rachis unwinged; stipules minute, early deciduous. Inflorescence a racemiform thyrse, with flowers in lateral cincinni, and often bearing a pair of tendrils at the base of the rachis. Flowers zygomorphic, functionally staminate or pistillate; calyx of 4 or 5 sepals; petals 4, distinct, white, with a hood-shaped appendage; nectary disk unilateral, 4-lobed or with 2 corniform projections; stamens 8, the filaments unequal, connate at base, the anthers dorsifixed; ovary 3-carpellate, each locule with a single ovule, the style slender, the stigmas 3, recurved. Fruit an inflated, membranous, capsule, the septa persistent after dehiscence of valves. Seeds spherical, black, with a small, white, cordate hilum.