143 
outline, exceeding the peduncles, 2 or 3-pinnate; pinne and segments 5 or 7, oblong 
and incised: umbels few-rayed, with no involucre, and involucels of oblong or lan- 
ceolate bractlets united at base and exceeding the yellow flowers: fruit about 6 mm. 
long, with 6 or 8 thin wings: oil-tubes several in the intervals,—Gravelly hills, wes- 
tern Texas. 
11. CYNOSCIADIUM DC. 
Glabrous annuals, with pinnately divided cauline leaves (leaflets lin- 
ear), mostly undivided lower and radical leaves, involucre and involu- 
cels of linear bracts, white flowers, persistent cal yx-teeth, ovoid glabrous 
fruit, prominent corky ribs (the laterals much the largest and forming a 
broad corky margin), conical stylopodium, and solitary oil-tubes. 
1. C. digitatum DC. Siender, 3 to 6 dm. high: radical leaves linear-lanceolate, 
entire; cauline leaves palmately 3 to 5-parted: umbels irregular, mostly 3 to 8-rayed ; 
rays about 2.5 cm. long; pedicels very unequal, 6 to 20 mm. long: fruit 2mm. long, 
contracted into a neck at summit, with very promineut ribs and minute calyx-teeth.— 
Wet ground, northeastern Texas. 
2. C. pinnatum DC. Smaller: cauline leaves pinnately divided into a few distant 
segments (terminal one much the largest); radical leaves similar or often entire: 
umbels 5 to 10-rayed; rays 1 to 2.5 em, long; pedicels 2 to 8 mm. long: fruit 3 mm. 
long, not beaked at summit, with less prominent ribs and very prominent calyx-teeth. 
—Wet ground, central and northern Texas. Var. PUMILUM Eng. is a cespitose form. 
12. ERYNGIUM L. 
Glabrous perennials, with mostly rigid coriaceous Spinosely-toothed 
or divided leaves, white or blue flowers in dense bracteate heads, very 
prominent rigid and persistent calyx-lobes, ovoid fruit covered with 
hyaline scales or tubercles, ribs obsolete, no stylopodium, and oil-tubes 
mostly 5 (3 dorsal and 2 commissural).—The outer bracts form the invo- 
lucre, the inner ones, bractlets, intermixed with the flowers, represent 
the involucels, Care must be taken not to confuse the prominent rigid 
calyx-lobes with the bractlets. 
"Stout, with parallel-veined elongated linear coriaceous leaves, which are mostly entire 
or with margin sparingly bristly. 
1. B. yuccefolium Mx, From 3 to 18 dm. high, branching above: leaves broadly 
linear (from 4 mm. to over 25 mm. wide), tapering to a point, with remotely bristly 
margins, the lower sometimes becoming 6 to 9 dm, long: heads pedunculate, ovate- 
globose (18 mm. long), with ovate-lanceolate mostly entire cuspidate-tipped bracts 
shorter than the head, similar bractlets, and short ovate calyx-lobes. —A common 
northern species of dry or damp soil and extending into northern and eastern Texas. 
Exceedingly variable as to height and size of leaves. 
**Tall and slender, with thick linear to oblong entire or somewhat toothed (not spiny) 
leaves on long fistulous petioles. 
2. EB. Virginianum Lam. Slender, 3 to 9 dm. high, branching above: radical and 
lower cauline leaves linear to oblong-lanceolate (petioles sometimes 3 dm, long), 
entire ur with remote small hooked teeth; upper cauline leaves sessile, spiny- 
toothed or laciniate: heads ovate-oblong (12 mm. long), with lanceolate spiny- 
toothed or entire reflexed bracts mostly as long as the head, bractlets with 3 spiny 
cusps (the middle one largest), and prominent lanceolate acuminate-cuspidate calyx- 
lobes equaling or exceeding the bractlets.—A species of the Gulf States, margins of 
ponds and streams, and extending into eastern Texas, probably within our range, 
