Umbels compound, us. lf-opposed, often subterminal; involucral bracts and bracteoles few to 0; calyx-teeth 0 or minute; petals white, ovate, acute, ± inflexed. Fr. subovoid, laterally compressed; commissure narrow; mericarps distinctly, obtusely 5-ribbed; vittae large, in furrows. Annual to perennial glab. herbs with compound lvs. Widely distributed genus of some 50 spp.

Glabrous annual, biennial or perennial herbs, usually with taproots, sometimes rooting at nodes. Lvs 1-3-pinnate; segments broad or narrow. Umbels usually compound, often ± sessile and lf-opposed, sometimes shortly pedunculate; bracts few and simple or 0; bracteoles several or 0. Petals white or greenish, regular, with entire, obtuse to acute, usually inflexed apex; calyx teeth minute or 0. Fr. ovoid-oblong to subglobose, slightly flattened laterally, not beaked, spinless; commissure narrow; ribs 5 per mericarp, equal, stout or slender; vittae solitary in furrows.