Zizia aptera (A. Gray) Fern.

Zizia aptera (A. Gray) Fernald, Rhodora 41: 441. 1939
Zizia cordala Koch; DC. Prodr. 4: 100. 1830. Not Smyrnium cordatum Walt. 1788.
Thaspium trifoliatum var. apierutn A. Gray, Man. ed. 2. 156. 1856.
Carum cordatum Benth. & Hook.; Coult. & Rose, Rev. N. Am. Umbell. 127, as syn. 1888. Not
Smyrnium cordatum Walt. 1788. Zizia aptera var. occidentalis Fernald, Rhodora 41: 444. 1939.
Plants 3-6 cm. high; basal leaves cordate to oval, excluding the petioles 4—7 cm. long, 3-5 cm. broad, simple or occasionally ternate, crenate-dentate; petioles 5-12 cm. long; cauline leaves ternately divided, the divisions lanceolate, coarsely serrate and often lobed; peduncles 6-12 cm. long; involucel of a few inconspicuous, linear, acute bractlets 1-2 mm. long, shorter or longer than the pedicels; rays 12-16, spreading-ascending, unequal, 1-3 cm. long; pedicels 1-3 mm. long; fruit oblong to oval, 2-4 mm. long, 2 mm. broad, the ribs filiform; oil-tubes solitary in the intervals, 2 on the commissure; seed-face slightly concave. Type locality: New York and New Jersey, collector unknown.
Distribution: Eastern Canada to Georgia, west to British Columbia, Washington, western Oregon, and Utah (Grant 1392, Nelson 8800).