COMPOSITE. (COMPOSITE FAMILY.) 
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toothed, on slender petioles ; the upper sessile; corymb flat-topped; 
rays 12 -15. — Mountains of Pennsylvania (Pursh), anil southward. 
May. —Plant X°-SP high, nearly leafless above. 
52- ARNICA, L. Arnica. 
Heads many-flowered, radiate, the rays pistillate. Seales of the 
bell-shaped involucre lanceolate, equal, somewhat in 2 rows. Re¬ 
ceptacle flat, fimbrillate. Achenia spindle-shaped. Pappus a 
single row of rather rigid and strongly roughened-denticulate 
bristles.—Perennial herbs, chiefly of the mountains and cold 
northern regions, with simple stems, bearing single or corymbed 
large heads and opposite leaves. Flowers yellow. (Name thought 
to be a corruption of P tar mica.) 
1. A. mollis Hook. Soft-hairy; stem leafy, bearing 1 to 5 
heads ; leaves thin, veiny, smoothish when old, toothed ; the upper 
ovate-lanceolate, closely sessile; the lower narrower, tapering into a 
margined petiole; scales of the involucre pointed; pappus almost 
plumose. - Alpine rivulets, &c„ White Mountains of N. Hampshire 
and mountains of N. New York. July. 
Tribe V. CYNAREiE. The Artichoke or Thistle Tribe. 
Style in the perfect flowers often thickened near the summit; 
the branches distinct or concreted, minutely pubescent externally ; 
the stigmatic lines reaching their apex and there confluent. 
(Heads discoid, mostly large.) 
53. CENTAUREA, L. Star-Thistle. 
Heads many-flowered; the flowers all tubular, the marginal 
mostly falsely radiate and larger, sterile. Receptacle bristly. In¬ 
volucre imbricated, the scales margined or appendaged Achenia 
compressed. Pappus wanting, or of a few bristles. — Her wit 
alternate leaves and single heads. (Named from the Centaur, 
Chiron.) , _ . . 
1 C cianus, L. (Blue-Bottle.) Scales of the globular 
involucre fringe-margined; rays longer than the disk; pappus i veyy 
short; stem erect, branching; leaves ^near enure, or toothed at the 
base. ® -Road-sides, escaped from gardens. July. - Flowers 
blue, varying to purplish or white. t 
2. C. nigra, L. (Knapweed.) Scales of the globular mvo- 
lucre appendaged, and with a stiff black fringe j rays wantin 3 ; p 
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