Description from Flora of China
Herbs annual or perennial, erect or spreading, ± decumbent, rarely shrubs, pubescent or glabrous. Leaves entire to pinnatifid; stipules glandular. Flowers borne in racemes. Sepals 4-7. Petals 4-7, usually lobed, clawed at base. Stamens 7-40, forming a disc at base. Carpels 3-6, united at base; placentas 3-6; ovules numerous. Capsule 1-valved, opening widely at maturity.
About 60 species: E and N Africa, C and SW Asia, N Atlantic Islands, S Europe, widely naturalized elsewhere; three species (introduced) in China.