COMPOSITAB 153 



219. ARNICA, L. 



[Name supposed to be corrupted from Ptarmica.] 



Heads many -flowered, radiate ; ray-florets pistillate. Involucre cam- 

 panulate; scales somewhat in 2 series, lanceolate, equal. Akenes 

 tapering downwards, somewhat ribbed ; pappus a single row of 

 rough bristles. Receptacle flat, fimbrillate. Perennials : leaves op- 

 posite; heads large, single, or few and loosely corymbed; flowers 

 yellow. 



1. A. nudicaftlis, Ell. Hirsute ; stem scape-like, with a pair 

 of lance-ovate sessile leaves near the middle ; radical leaves ovate- 

 oblong, clustered, decussate. 

 NAKED-STEM ARNICA. Leopard's Bane. 



Stem 1 to 2 feet high, simple, with a few peduncle-like branches at summit. 

 Radical leaves 2 to 4 inches long, sessile, nearly entire, usually 3 or 4 pairs, spread- 

 ing on the ground, strongly nerved. Heads of flowers large. Akenes sparsely pi- 

 lose, nearly black when mature. 

 Hab. Moist meadows ; Penn township : rare. Fl. June. Fr. July. 



Obs. Prof. GRAY seems to haye overlooked this species, when 

 preparing his Manual. It appears to be truly indigenous, in the 

 locality named. 



TRIBE 5. CYNA'REAE. 



Heads discoid, usually large, sometimes diaicous; involueral scales imbricated In 

 many series ; style, in the perfect florets, often nodosely thickened near the sum- 

 mit ; branches distinct, or concrete, puberulent externally, the stigmatic lines 

 extending to their apex, and there confluent. 



220. CEtfTAURITA, L. 



[Named from the Centaur, Chiron ; who, it is said, used the plant.] 

 Heads many-flowered ; florets unequal, the marginal ones mostly 

 enlarged, or falsely radiate, and neutral. Involucre roundish-ovoid ; 

 scales variously margined, or appendaged. Akenes compressed ; 

 pappus one or more series of rough bristles, or sometimes wanting. 

 Receptacle bristly. Leaves alternate ; heads solitary. 



1. C. Cy^anus, L. Hoary-lanuginous ; leaves lance-linear, sessile> 

 entire, or toothed at base ; involueral scales fringe-margined ; pap- 

 pus very short. 

 BLUE CENTAUREA. Blue-bottle. Ragged Robbin. Blue Bonnets. 



Annual. Stem 18 inches to 3 feet high, much branched. Leaves 2 to 6 inches 

 long, sometimes pinnatifid near the base. Heads of flowers pedunculate ; florets. 

 mostly blue, the marginal ones obsoletely pistillate, enlarged and funnel-form, 

 with a long tube. Akenes with a lateral areola. 

 Hob. Gardens, and waste places. Nat. of Europe. Fl. July, Fr. Aug. 



Obs. Partially naturalized; and, if not attended to, may become 

 a troublesome weed, as it is in Europe. 



221. CYtfA^RA, Vaill. 



[Gr. Kyon, kynos, a dog; the involucral spines resembling dog's teeth.] 

 Heads many-flowered; florets all equal. Involucre ovoid; scales 

 coriaceous, produced into a lanceolate appendage which is spines- 

 cent at apex. Anthers with an obtuse appendage. Style-branches 



