Centaurea. COMPOSITE. 405 



= = Heads large, oblong or cylindraceous, commonly solitary and pedunculate: involucral 

 bracts comparatively large, gradually acuminate into a nuicronate cusp or \vt_-uk and short 

 prickle, glabrate, the viscid dorsal ridge narrow: corollas purple: leaves when young canes- 

 cently floccose-woolly beneath, oblong-linear or narrowly lanceolate. 



C. repandus, ELL. A foot or two high, leafy : leaves mostly uiululate-lobulate, rather 

 densely prickly at margins : heads inch and a half long : involucre narrow-campanulate. 

 Sk. ii. 269; Gray, 1. c. Cirsium repandum, Michx. Fl. ii. 89; DC. Proclr. vi. G51. Carduus 

 repandus, Pers. Syn. ii. 386. C. Vinjiniuiuis, Walt. Car. 195 ? Dry pine barrens, N. Caro- 

 lina to Florida. 



C. Lecontei, GRAY. Stem slender but rigid, commonly simple and bearing a single con- 

 spicuously pedunculate head (of full 2 inches in height) : leaves sparsely dentate or piimatifid- 

 lobulate, with scattered prickles : involucre cylindraceous. Proc. Am. Acad. x. 39. C'nicus 

 Virginianus, Hook. Comp. Bot. Mag. i. 48. Cirsium Lcmntei, Ton-. & Gray, Fl. ii. 458. 

 Wet pine barrens, Georgia to Florida and Louisiana; first coll. by LtConle. 



==== = Heads inch and a half high, rather broad: involucre arachnoid-woolly; its principal 

 bracts broad and pointless. Atlantic species. 



C. muticus, PURSII. Obscurely arachnoid when young and with some villosity : stem 3 to 

 8 feet high, branching above: leaves deeply pinnatifid, sparsely weak-prickly, glabrate : in- 

 volucre sometimes glabrate in age : bracts with broad and short viscid ridge or spot just 

 beneath the obtuse or acutish sometimes mucronulate apex, lowest ovate or oblong and very 

 short, innermost linear : flowers rose-purple. Gray, 1. c. C. gluthiosus, Bigel. Fl. Bost. ed. 2, 

 291, not Lam. Carduus muticus and perhaps C. ijhtbcr, Nutt. Gen. ii. 129. Cirsium muti- 

 cum, Michx. Fl. ii. 89; DC. 1. c. ; Torr. & Gray, Fl. ii. 458, excl. syn. of the var.?, which is 

 a more rigid form, growing in open ground. C. Bitjelovii, DC. 1. c. Low ground and 

 shady swamps, Newfoundland to Saskatchewan, Florida, and Louisiana. 



199. ONOPOBDON, Vaill. COTTON THISTLE. (Old Greek name, mean- 

 ing Asses' Thistle.) Large and stout biennials of the Old World, one sparingly 

 naturalized; fl. late summer. DC. Prodr. vi. 617. Onopordum, L. 



O. ACANTHIUM, L. White with cottony wool: stem 3 to 9 feet high, branching, winged 

 throughout by decurreuce of the large oblong sinuate-lobed and prickly leaves ; wings sinu- 

 ate, very prickly : heads pretty large : involucre globular, arachnoid or partly glabrate ; 

 bracts rigid, subulate and prickly tipped, squarrose : corollas light purple or paler: pappus 

 fuscous, scabrous, not twice the length of the slightly rugose akene. Fl. Dan. t. 909 ; Eugl. 

 Bot. t. 907. Waste grounds near dwellings and roadsides in Atlantic States, not abundant. 

 (Nat. from Eu.) 



200. StLYBUM, Vaill. MILK THISTLE. (SiXu/Sos, ancient Greek name 

 of an edible-stemmed Thistle, perhaps the present plant.) Single species. 



S. MARIAXUM, G^ERTX. Prickly-leaved biennial or annual, glabrate or nearly glabrous ; with 

 ample sinuate or pinnatifid green leaves, blotched with white along the veins: corollas rose- 

 purple, deeply cleft. Escaped from gardens in a few places, also a ballast-weed, disposed to 

 be naturalized southward, especially in California: fl. summer. (Adv. from Eu.) 



201. CENTAUKfiA, L. STAR THISTLE, &c. (Kevravpeiov, plant of the 

 Centaurs, name applied by the herbalists to two or three widely different genera.) 

 An immense genus in the Old World, one species only indigenous to N. 

 America, two or three in Chili. - - Centaurea &, Carbenia (Adaus.), Bcnth. & 

 Hook. Gen. PI. ii. 477, 482. 



1. CARBENIA. Akenes terete, strongly many-striate, with lateral scar, the 

 corneous margin at summit 10-dentate : pappus double, each of 10 aristiform 

 bristles, outer longer and naked, inner short and fimbriolate : anthers with elon- 

 gated cartilaginous terminal appendages, which are connate to their blunt tips : 



