This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol2", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
[Discopleura DC. Mem. Omb. 38. 1829.]
Annual erect glabrous branching herbs, with pinnately or ternately dissected leaves, and compound umbels of white flowers. Bracts of the involucre several, filiform or dissected in our species. Involucels present. Calyx-teeth obsolete. Petals obovate, the apex inflexed.
Stylopodium conic; fruit ovate, slightly compressed, glabrous. Carpels dorsally compressed, the dorsal and intermediate ribs prominent, slender, the lateral ones very thick and corky; oil-tubes solitary in the intervals. Seed-face flat. [Greek, referring to the finely divided leaves.]
About 4 species. Besides the following, another occurs in Texas and one in the East Indies. Type species: Ammi capillaceum Michx.
Involucral bracts mostly pinnate; fruit 1" - 1 1/2" long.
Involucral bracts short, entire; fruit 1/2"-3/4" long.
217. 1830. P. missouriense Coult. & Rose, Contr. Nat. Herb.
12: 444. 1909.
Slender, 1°-2° high or more, the branches ascending or sometimes divaricate. Leaves finely dissected into filiform segments, the upper sessile, the lower more or less petioled; involucral bracts, or some of them, pinnately parted; involucels of several linear bracts; umbels 2-4' broad, 5-20-rayed, the rays 1'-2' long; pedicels 2"-8" long; fruit ovate, acute, 1"-1 1/2" long.
Peucedanum verticillatum Raf. Fl. Ludov. 81. 1817?
Discopleura Nuttallii DC. Mem. Omb. 38. 1829.
Discopleura capillacea var. Nuttallii Coult. & Rose, Bot. Gaz. 12: 292. 1887.
Similar to the preceding species, but generally stouter, 2°-3° high, the branches nearly erect. Umbels 7-25-rayed; bracts of the involucre linear, entire, short, those of the involucels minute; fruit nearly orbicular, obtusish, about i" long.