406 COMPOSITE. Centaurea. 



head surrounded by large and leafy accessory bracts. Oarbeni, Adaus. Fam. 

 ii. 11G. Cfiicus, Gcertn., DC., not L. 



C. BENEDTCTA, L. (BLESSED THISTLE.) Low and branching annual, hirsute or pubescent : 

 leaves prominently reticulated, siuuate-piuuatiftd or laciniate-deutate, the teeth or margins 

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

 base: heads sessile, inch and a half high, equalled by the oblong involucral leaves: proper 

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

 aristiform or spinesceut 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 akcue. Spec. ed. 2, ii. 1296 ; 

 Sibth. Flora Grasca, t. 906. Cnicus benedirtus, L. Spec. ed. 1, i. 826 ; Gasrtn. Fruct. ii. t. 162 ; 

 DC. Prodr. vi. 606 ; Torr. & Gray, Fl. ii. 455. Waste grounds, at seaports and elsewhere 

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

 from Eu.) 



2. CENTAUREA proper. Akenes more or less compressed or quadrangular : 

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

 lucre globular or ovoid. 



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

 akene lateral. 



-1 Bracts of the involucre (or some of them) armed with a rigid spine or prickle, and also more 

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

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

 Calcilrapa, Juss. 



C. CALcfTRAPA, L. (STAR THISTLE.) Low, much branched, diffusely spreading, green, gla- 

 brate or hairy : leaves narrow, laciuiate-piunatifid ; uppermost somewhat involucrate-crowded 

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

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

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

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

 ballast- weed. (Nat. from En.) 



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

 lyrate-piunatifid ; cauline lanceolate and linear, mostly entire, decurrent on the branches in 

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

 volucre tipped with along spreading spine, having one or two spiuules 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. Eugl. Bot. t. 243; 

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

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



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

 what woolly at first : radical leaves lyrate-piuuatifid ; 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, 

 which is pectiuately spiuulose towards its base ; innermost with simply spinesceut tip ; outer- 

 most usually with the central spine reduced and the spiuules palmate : corollas yellow : 

 pappus of very unequal rigid bristles or squamolla; : akeue lightly costate. Sibth. Flora 

 Gi-ieca, t. 909 ; Reicheub. Ic. Fl. Germ. xv. t. 796 ; Gray, Bot. Calif. 1. c. Fields, California 

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



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

 ate-ciliate or lacerate appendage. Jacea, Platylophtis, Cyanus, &c., Cass. 



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



C. NfKA, L. (KNAPWEED, HARDHEADS.) A foot or two high, branching, roughish-pubescent : 

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

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

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

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



