Herbs perennial, climbing. Rhizomes absent. Lateral branches penetrating leaf sheaths. Leaves alternate. Inflorescences borne at each node, opposite leaves, emerging from mouth of leaf sheath, each a large panicle of numerous cincinni; cincinni each subtended by an involucral bract; bracts similar to leaves, becoming smaller toward apex of cincinnus. Flowers actinomorphic, those of basal cincinnus bisexual, others male or bisexual. Sepals free, boat-shaped, galeate at apex. Petals free, linear-spatulate, white. Stamens 6, all fertile, equal; filaments densely torulose-hairy; anther locules parallel, ellipsoid, longitudinally dehiscent. Ovary 3-loculed; ovules 2 per locule. Capsule 3-valved, ellipsoid, beaked; seeds 2 per valve, rugose; hilum linear.