Arracacia atropurpurea (Lehm.) Benth. & Hook. fil. ex Hemsl.

Arracacia atropurpurea (Lehm.) Benth. & Hook.; Hemsl Biol. Centr. Am. Bot. 1: 564. 1880.
Pentacrypla atropurpurea Lehm. Ind. Sem. Hort. Hamburg 17. 1828. Arracacia irazuensis Kuntze. Rev. Gen. 1: 265. 1891. Arracacia Luxeana Coult. & Rose, Bot. Gaz. 18: 55. 1893. Arracacia humilis Rose, Contr. U. S. Nat. Herb. 8: 336. 1905.
Slender, caulescent, branching from a shrubby base, 6-40 dm. high, glabrous or the inflorescence more or less puberulent; leaves oblong-ovate to ovate-deltoid in general outline, excluding the petioles 8-20 cm. long, 2-3-ternate, the leaflets oblong-ovate, obtuse to acute at the apex, rounded or cuneate at the base, distinct and petiolulate or the terminal confluent, 2-8 cm. long, 1-3.5 cm. broad, rather finely doubly serrate and often incised toward the base; petioles S— 16 cm. long, sheathing at the base; cauline leaves reduced upwards, with conspicuous sheaths; inflorescence branched, the peduncles slender, 1-3 dm. long; involucre wanting, or of a single foliaceous bract; involucel of 1-3 (or 6) conspicuous, lanceolate, ovate or cuneate, acute, dentate, lacerate, or rarely entire bractlets, 5-35 mm. long, 1-8 mm. broad, exceeding the sterile flowers and often the fruit; fertile rays 3-8 (or 18), slender, spreading, unequal, 3-9 cm. long; fertile pedicels 5-10, slender, spreading, unequal, 3-12 (or 22) mm. long; flowers purple or greenish-yellow, the petals obovate; stylopodium low-conic, the styles short, recurved; carpophore 2-cleft to the base, stout; fruit oblong to oblong-oval, 4-7 mm. long, 2-4 mm. broad, glabrous or even glaucous, tapering at the apex, the ribs acute; oil-tubes large, solitary in the intervals, 4 on the commissure, or often with some small accessories; seed channeled under the tubes, the face sulcate.
Type locality: "In terris Mexicanis," collector unknown.
Distribution: Nuevo Le6n and San Luis Potosi, south to Guatemala, Costa Rica, and Panama