142 
often corky back, laterals forming broad thick corky wings, no sty- 
lopodium, and 12 to 13 oil-tubes about the seed besides many scattered 
through the thick corky pericarp. 
1. P. Nuttallii DC. Mostly glabrous except the pubescent pedicels and involu- 
cels, 6 to 9 dm. high: leaf-segments cuneate and incised ; upper leaves opposite and 
s.cleft : umbel 6 to 12-rayed; rays about 25 cm. long; pedicels 2 to 4 mm. long: 
fruit 6 to 10 mm. long.—Apparently throughout eastern and northern Texas. 
9. PEUCEDANUM L. 
Short-caulescent or acaulescent dry ground perennials, with fusiform 
or tuberous roots, ternate or pinnate to dissected leaves, no involucre, 
involucels mostly present, yellow or white flowers, obsolete or evident 
calyx-teeth, oblon g to suborbicular glabrous to tomentose dorsally flat- 
tened fruit, filiform dorsal and intermediate ribs, lateral wings broad 
and thin, no stylopodium, and 1 to 8 oil-tubes in the intervals. —A very 
large and perplexing genus of western United States, but scantily 
represented in Texas. 
1. P feeniculaceum Nutt. Acaulescent, tomentose or glabrous, with peduncles 20 
to 30 em, long: leaves finely dissected, ternate then pinnate, with short filiform seg- 
ments: umbel rather equally 3 to 12-rayed, with gamophyllous involucels 5 to 7- 
cleft and with conspicuously hairy margins; rays 2.5to 6.5 cm, long; pedicels 6 to 
10 mm. long: flowers yellow: fruit broadly oblong, 5 to 6 mm. long, 4 mm. broad, 
with wings half as broad as body, and prominent dorsal and intermediate ribs: o1l- 
tubes 1 to 3inthe intervals,—A species of the westera plains, extending into north. 
ern and eastern Texas. 
2. P. nudicaule Nutt. Acaulescent or shortly caulescent, with peduncles 7.5 to 20 
em. high, pubescent from a thick elongated (often tuberous) root: leaves bipinnate, 
the small oblong segments entire or toothed: umbel unequally 5 to 8-rayed, with in- 
volucels of scarious-margined (often purplish) lanceolate bractlets; rays 1 to 3.5 cm. 
long ; pedicels 5 to 7 mm. long: flowers white or pinkish : fruit almost round, emar- 
ginate at base, glabrous, 5 mm. long, 4mm, broad, with wings not as broad as body, 
and indistinct or obsolete dorsal and intermediate ribs; oil-tubes mostly solitary.—- 
A very early bloomer of the plains west and north of Texas, and doubtless in north- 
ern Texas. 
10. CYMOPTERUS Raf. 
Mostly low and glabrous perennials (often cespitose) from a thick 
elongated root, with more or less pinnately compound leaves, mostly 
no involucre and prominent involucels, white, purple or yellow flowers, 
more or less prominent calyx-teeth, usually globose fruit with 6 to 10 
broad thin and equal wings, depressed stylopodium, and oil-tubes one 
to several in the intervals. 
1. C. montanus Torr. & Gray. Leaves clustered at the summit of the very short 
stem, glaucous and glabrous (rarely slightly puberulent), pinnate or bipinnate; pin- 
ne oblong, pinnatifid with oblong obtuse entire or toothed lobes: peduncles 2.5 to 
is em. high; rays6to18 mm. long; pedicels very short; involucre and involucels 
of mostly broad membranaceous usually green-veined bracts, more or less united: 
flowers white: fruit oblong in outline, 6 to 12 mm. long, the 6 to 10 wings broad and 
thin (thick at base): oil-tubes 1 to 3 in the intervals.—Northern and western Texas. 
2, C, Fendleri Gray. Low, subcaulescent: leaves oblong or ovate-lanceolate in 
