Rhodosciadium dissectum Coult

Rhodosciadium dissectum Coult. & Rose, Contr. U. S. Nat
Herb. 3:309. 1895.
Slender, from a swollen tuberous rootstock bearing dead leaf-sheaths, 6-9 dm. high, the foliage hispidulous; leaves deltoid in general outline, excluding the petioles 8-12 cm. long, ternately or ternate-pinnately decompound, the ultimate divisions linear to linear-lanceolate, acute, 1-5 mm. long, hispidulous on the veins and rachis; petioles slender, 4-14 cm. long; inflorescence 1-2-trifurcate with some alternate peduncles below and some lateral branches weakly dichasial, the peduncles slender, 1.5-3 cm. long, or the terminal 6.5 cm. long, each subtended by a small bract; involucre wanting; involucel of 1-several linear bractlets 2-3 mm. long, shorter than the flowers and fruit; rays 3-5, spreading-ascending, subequal, 1-2.5 cm. long; pedicels 1-3 mm. long; petals purple; fruit ovoid, cordate at the base, narrowed at the apex, 5-7 mm. long, 4-6 mm. broad, the dorsal ribs prominent, the lateral wings narrower than the body; seed-face plane to slightly concave.
Type locality: " Dry calcareous hills. Las Sedas, Oaxaca," Pringle 4764. Distribution: Oaxaca (Rose &* Hough 4630).