Herbs, perennial. Rhizomes creeping, filiform, terminated by a tuber; tuber white, giving rise to following year’s plant. Stems 1 or 2, glabrous. Basal leaves 1-3, ternate to biternate; cauline leaves 2, opposite, rarely alternate; all leaves petiolate, 3-cleft or compound. Inflorescences cymes, terminal, in headlike clusters, or racemelike. Flowers yellowish green, sessile, 4- or 5-merous. Calyx shallowly cup-shaped; lobes of terminal flower 2, lobes of lateral flowers 3. Corolla rotate; tube short; lobes 3-6 in terminal flower, 4-6 in lateral flowers, lobes papillate adaxially. Fertile stamens 4 or 5, inserted on corolla tube; filaments 2-fid to middle or to base; anthers 1-celled, peltate, extrorse, longitudinally dehiscent; inner stamens reduced to glandular papillae. Ovary inferior to semi-inferior; carpels 4 or 5, locules 4 or 5; styles 4 or 5, connate at base; stigmas capitate. Fruit berrylike, fleshy. x = 9, 2n = 36, 54, 108.
"Fls half-epigynous, with a shortly prolonged hypanthium, mostly 5 in a compact, head-like terminal cyme; sep of the central fl commonly 2, of the lateral ones 3; cor rotate, that of the central fl regular and commonly 4-lobed, that of the lateral ones slightly irregular and commonly 5-lobed; stamens paired at the sinuses of the cor, each bearing a single pollen-sac; carpels several, most often 4 in the central fl and 5 in the lateral ones, united to form a compound ovary with distinct styles and capitate stigmas. Monospecific."