Description from Flora of China
Herbs, perennial, with tubers, glabrous. Stem erect, herbaceous, unbranched. Cauline leaves usually 2(-5), alternate, 2-3 × pinnately compound, stipulate. Raceme simple, terminal, bracteate. Flowers yellow. Sepals 6, petaloid. Petals 6, yellow, nectary-like, much shorter than sepals. Stamens distinct. Pistil simple; carpels 1; ovary inflated, not stipitate or shortly so; ovules 2-4; placentation basal. Achene globose, utricle-like, indehiscent or irregularly lacerate on top of fruit. Seeds in fruit, usually 2; aril absent.
About three or four species: north temperate zone; one species in China.
(Authors: Ying Junsheng (应俊生 Ying Tsun-shen); David E. Boufford, Anthony R. Brach)