Annual or perennial, erect or decumbent herbs. Leaves usually lobed, sometimes entire. Flowers axillary, solitary or fascicled or in pseudo-raceme on terminal branches, pedicellate. Epicalyx segments 6-12, connate below. Calyx 5-lobed. Corolla small, usually up to 2 cm long. Staminal tube cylindric, pubescent; anthers brownish purple. Mericarps 8-25, each 1-celled, wingless, dorsally with prominent nerve.