Centaurea. COMPOSITE. 405 



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

 bracts comparatively large, gradually acuminate into a mucronate cusp or weak 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 undulate-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. Prodr. vi. 651. Cardmis 

 repandus, Pers. Syn. ii. 386. C. Virginianus, "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 pinnatifid- 

 lobulate, with scattered prickles : involucre cylindraceous. — Proc. Am. Acad. x. 39. Cnlcus 

 Virginianus, Hook. Comp. Bot. Mag. i. 48. Cirsium Lecontei, Torr. & Gray, Fl. ii. 458. — 

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



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

 bracts broad and pointless. Atlantic species. 



C. muticus, Ptjrsii. 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. glutinosus, Bigel. Fl. Bost. ed. 2, 

 291, not Lam. Carduus muticus and perhaps C. glaber, 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. Bigelovii, DC. 1. c. — Low ground and 

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



199. ONOPCRDON, 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. acaxthium, L. White with cottony wool: stem 3 to 9 feet high, branching, winged 

 throughout by decurrence 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 ; Engl. 

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

 (Nat. from Eu. ) 



200. SlLYBUM, Vaill. Milk Thistle. (Si'av/Jos, ancient Greek name 

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



S. MariXnum, Gjertn. 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. CENTAURfiA, 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 (Adans.), Benth. & 

 Hook. Gen. PL ii. 477, 482. 



§ 1. Cakbenta. 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 : 



