Fr oblong or ovoid, subterete or slightly flattened dorsally, some of or all the ribs prominently winged; oil-tubes solitary in the intervals, 2 on the commissure; carpophore wanting; umbels terminal and lateral, large, compound; bracts none; umbellets small; fls all pedicellate; involucel of small, narrow bractlets; sep ovate or obovate; pet yellow (or cream) or purple; stylopodium wanting; branching perennials with a rootcrown or short rhizome and a cluster of fibrous or fleshy-fibrous roots, and with variously compound lvs (or the lowest lvs simple), resembling Zizia in aspect. 3, N. Amer.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
