Fr elliptic or elliptic-oblong, flattened dorsally; dorsal ribs corky, prominent, acute or narrowly winged, the lateral ribs more evidently winged; oil-tubes 1-4 in the intervals, 2-8 on the commissure; carpophore bifid to the base, or nearly so; umbels large, compound; bracts foliaceous or narrow or none; rays numerous; umbellets small and densely fld; bractlets several, narrow, ±scarious; sep none; pet white; stylopodium conic; erect perennials from 1-several thickened roots, glabrous below, often scabrous-puberulent in the infl, with twice or thrice ternate-pinnately compound lvs and deeply lobed or incised lfls. 10, N. Amer. and Eurasia.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.