Description from Flora of China
Herbs, biennial or perennial, rarely annual, lactiferous. Taproot slender. Stems erect or ascending, terete, glabrous or villous. Basal leaves many, petiolate; leaf blade usually pinnatifid; lobes ampliate to sheath at base, serrate or crenate at margin. Cauline leaves alternate, sessile, cordate-amplexicaul at base, incised or undulate at margin. Flowers solitary, terminal or axillary, usually long pedunculate, large. Sepals 2, caducous, glabrous or villous. Petals 4, convolute in bud, yellow, orange, or red. Stamens numerous. Ovary terete or linear, 2-carpellate, placentas 2-pseudo-loculed from cellular spongy septum connecting placentas; stigmas 2-divided, almost sessile. Capsule terete, slender, horned and often shortly tridentlike at apex, when mature divided into 2 narrow segments from apex to base or rarely from base to apex. Seeds many, ovoid-reniform, seed coat alveolate, not carunculate.
Twenty-one to 25 species: mainly in temperate Europe, the Mediterranean region, also in C to SW Asia; three species in China.
(Authors: Zhang Mingli (张明理); Christopher Grey-Wilson)