406 COMPOSIT^E. Ccntaurea. 



head surrounded by large and leafy accessory bracts, — Carheni, Adans. Fam. 

 ii. 116. Cnicus, Gaertn., DC, not L. 



C. BEXEDICTA, L. (Blessed Thistle.) Low and branching annual, hirsute or pubescent : 

 leaves prominently reticulated, sinuate-pinuatifid or laciuiate-deutate, the teeth or mai-gins 

 weakly prickly; lower attenuate at base; upper narrowly oblong, partly clasping by bro;id 

 base : heads sessile, incli and a half high, equalled by the oblong iuvolucral leaves : proper 

 involucre of thin-coriaceous bracts iu few ranks, all or most of them abruptly tipped with an 

 aristiforra or spinescent and pectiuately prickly spreading appendage : receptacle very 

 densely setose with long and soft capillary bristles : corollas light yellow : longer bristles of 

 the pappus alternating with inner and with the teeth of the akene. — Spec. ed. 2, ii. 129G; 

 Sibth. Flora Grceca, t. 906. Cnicus benedictits, L. Spec. ed. i. 826; Gcertn. Fruct. ii. t. 162; 

 DC. Prodr. vi. 606; Torr. & Gray, Fl. ii. 45.5. — Waste grounds, at seaports and elsewhere 

 near dwellings, in the Southern Atlantic States and iu California; not common. (Nat. 

 from Eu.) 



§ 2. Centaurea proper. Akenes more or less compressed or quadrangular : 

 pappus of indefinite (either scanty or numerous) bristles or narrow paleaj : invo- 

 lucre globular or ovoid. 



* Old World species, sparingly naturalized, with comparatively small heads : scar or insertion of 

 akene lateral. 



•i^ Bracts of the involucre (or some of tliem) armed with a rigid spine or prickle, and also more 

 or less spinulose along its sides or base : cartilaginous appendages terminating the anthers 

 conimouly elongated and connate: ours annuals, none with the marginal corollas enlarged. — 

 Calcitrajm, Juss. 



C. Calcitrapa, L. (Star Thistle.) Low, much branched, diffusely spreading, green, gla- 

 brate or hairy : leaves narrow, laciniate-pinnatilid ; uppermost somewhat iuvolucrate-crowded 

 at base of tlie sessile heads : principal bracts of the involucre becoming corneous, armed with 

 a widely spreading very long and rigid spine, which bears 2 or .3 spinules on each side at 

 base: corollas purple or purplish: pappus wanting. — Engl. Bot. t. 125; Torr. & Gray, Fl. 

 ii. 454. — Sparingly established at seaports from New York southward, chiefly as a mere 

 ballast-weed. (Nat. from Eu.) 



C. solstitiAlis, L. Erect, a foot or two high, canesceut with cottony wool: radical leaves 

 lyrate-pinnatifid ; cauline lanceolate and linear, mostly entire, decurrent on the l)ranches in 

 narrow wiugs : heads naked, somewhat pedunculate : intermediate bracts of the globular in- 

 volucre tipped with a long spreading spine, having one or two spinules at base ; outermost 

 bearing a few small palmate prickles ; innermost only scarious-tipped : corollas yellow : pap- 

 pus double ; outer of short and squamellate, inner of longer bristles. — Engl. Bot. t. 243 ; 

 Iveichenb. Ic. Fl. Germ. t. 795; Gray, Bot. Calif, i. 421. — Near San Francisco and San 

 Diego, California, sparingly introduced. (Nat. from Eu.) 



C. Mehiensis, L. Erect, 2 to 4 feet high, paniculately branched, cinereous-pubescent, some- 

 what woolly at first: radical leaves lyrate-pinnatifid; cauline lanceolate or linear, mostly 

 entire, narrowly decurrent on the branches : heads smaller, .sessile or 1-2-leaved at base : 

 principal bracts of involucre bearing a spreading slender spine of about their own length, 

 wiiich is pectiuately spinulose towards itsljase; innermost with simply spinescent tip; outer- 

 most usually witli the central spine reduced and the spinules palmate : corollas yeilow : 

 pappus of very unequal rigid bristles or squamella; : akene lightly costate. — Sibth. Flora 

 Grteca, t. 909 ; Reichenb. Ic. Fl. Germ. xv. t. 796 ; Gray, Bot. Calif. 1. c. — Fields, California 

 and Arizona, rather common. (Nat. from Eu.) 



•i— •)— Bracts of the involucre unarmed, most of them terminated by a scarious discolored fimbri- 

 ate-ciliate or lacerate appendage. — Jncea, Plafyloj>kus, Cynnus, &c., Cass. 



++ Perennials, with rose-purple flowers: pappus obsolete. 

 C. xfoRA, L. (Knapweed, Hardheads.) Afoot or two high, branching, roughish-pubescent: 

 leaves lanceolate and entire, or lower sparingly toothed : most of the iuvolucral bracts with 

 strongly pectiuately ciliate-fringed blackish appendages, these only conspicuous : flowers all 

 hermaphrodite, marginal ones not enlarged or rarely so. — Fl. Dau. t. 606 ; Eugl. Bot. t. 278. 

 — Fields, Newfoundland to E. New England. (Nat. from Eu.) 



