‘CENTAUREA COMPOSIT 4 ‘ $85 
Subtribe i, Centauriexr DC. Prodr. vi. 557. Achenes more or 
less compressed or quadrangular. Heads globular or ovoid. Pap- 
pus of indefinite, few or many, bristles or narrow palex. 
91 CENTAUREA L. Gen. n. 984, 
Perennial or annual herbs with alternate leaves and large or 
middlesized heads of tubular and various colored flowers. Invo- 
lucre ovoid or globose, its bracts imbricated in many series, ap- 
pressed, fimbrillate, or dentate. Receptacle flat, densely bristly. 
Marginal flowers usually neutral and larger than the central per- 
fect and fertile ones, or flowers all perfect in some species. Co- 
rolla-tube slender, the limb regular or oblique, 5-cleft or 5-lobed, 
the segments sometimes appearing like rays. Anthers sagittate 
at base. Style-branches short, somewhat connate, obtuse. 
Achenes compressed or obtusely 4-angled, usually smooth and 
shining, obliquely or laterally attached to the receptacle, sur- 
mounted by a disk with an elevated margin. Pappus of several 
series of bristles or scales, rarely none. 
* At least some of the involucral bracts armed with a rigid spine 
or prickle and also spinulose along its sides or base: cartilaginous ap- 
pendages of the anthers commonly elongated and connate. 
C. catcrrrapa L. Sp. 917. (Star THistuz). Low, much branched, — 
diffusely spreading, green, glabrate or hairy: leaves narrow, laciniate-pin- 
nat fid ; uppermost somewhat iuvolucrate-crowded at the base of the sessile 
heads: principal bracts of the involucre armed with a widely spreading 
very long and rigid spine which bears 2 or 3 spinules on each side at base: 
corollas purple or pinkish: pappus none. . Vancouver Island to California. 
Sparingly introduced from Europe. ; 
C. Mewitrensis L. 1. ¢.¥ Stems erect, 1-4 feet high, paniculately bran- 
ched, cinereous-pubescent, somewhat woolly when young: radical leaves 
lyrate pinnatifid; cauline{lanceolate or linear, mostly entire, narrowly 
decurrent on the branches: heads sessile or 1- or 2-leaved at base, prin- 
cipal bracts of the involucre bearing a slender spreading spine of about 
their own length, which is pectinately spinulose toward the base; inner- 
most with simply spinescent tips; outermost usually with the central 
spine reduced and the spinules palmate: corollas yellow: achenes lightly — 
costate: pappus of very unequal rigid bristles or squamelle, Rather com- 
mon in fields and waste places British Columbia to California and Arizona. 
Naturalized from Europe. 
+ + Bracts of the involucre unarmed, most of them terminated 
by a scarious discolored fimbriate-ciliate or lacerate appendage. 
C. Cyanus L Sp. 911. (Frenca Pink, Buiur Borriz.) Slender branch- 
ing annual: stems 1-6 feet high, whitened when young with floccose 
wool: leaves linear, entire, or the lower toothed or pinnatifid: heads na- 
ked on slender peduncles: involucral bracts rather narrow, furnished with 
short scarious teeth: marginal flowers neutral, with much enlarged 
radiform blue or white varying to pink purple or brown corollas: pappus 
of unequal bristles about the length of the achene. Very commun in fields 
Brit. Columbia to California. Introduced from Europe. 
92 ONICUS L. Sp. 826. (Burssep THISTLE.) 
Annual herbs with alternate sinuate or pinnatifid prickly. leaves, 
and large sessile heads of yellow tubular flowers solitary at the 
