Description from Flora of China
Herbs, annual, erect, dioecious or sometimes monoecious. Stems furrowed. Leaves alternate or opposite basally on stem, palmately compound, basally with 5-11 leaflets, apically with 1-3 leaflets; leaflet margin serrate. Male inflorescences axillary or terminal, a lax panicle. Male flowers: sepals imbricate; filaments straight in bud; rudimentary pistil small. Female inflorescences axillary, in a rosette. Female flowers: bracteoles leaflike; calyx rudimentary, membranous, appressed to ovary; styles 2, linear, caducous. Achene solitary, surrounded by persistent calyx, enclosed by bracts; endosperm fleshy; embryo curved; cotyledon fleshy.
One or two species: originally from Asia, but now widely cultivated elsewhere; one species in China.