860 COMPOSITAE (COMPOSITE FAMILY^ 



Some bracts with regularly pectinate or toothed margin or tip. 



Annual, with floccose white pubescence and simple entire linear or lanceo- 

 late leaves 5. (7. Cyanus. 



Biennials or perennials (exceptionally annuals), green; lowest leaves 

 usuaUy pinnatilid or coarsely toothed. 

 Middle and outer bracts pectinate or fringed two thirds to the base. 

 Leaves all pinnatifld ; green bodies of the involucral bracts con- 

 spicuous, their margins dark 6. C. Scahioaa. 



At least the upper leaves entire or merely short-toothed ; pale 

 bodies of the involuci'al bracts mostly hidden by the imbricated 

 appendages. 

 Heads 2-5 cm. broad ; involucral bracts with dark appendages . T. C. nigra. 

 Heads 6-12 cm. broad; bracts with pale brown or straw-colored 



appendages . %. O. americana. 



Middle and outer bracts pectinate only at the usually darker tip. 

 Lower leaves pinnatifld into linear or lanceolate segments, the upper 



mostly linear ; involucral bracts distinctly ribbed . . . . 9. C. maculosa. 

 Lower leaves elliptic or oblauceolate, lyrate-pinnatifid or coarsely 

 dentate, the upper similar; involucral bracts plane or obscurely- 

 ribbed . . . • 10. (7. vochin&nsis. 



1. C. CALCfxRAPA L. (Caltrops, Star Thistle.) Diffusely branched, 

 somewhat pubescent ; leaves spinulose-toothed ; heads sessile ; all but the inner- 

 most involucral bracts terminated by a stout divergent straw-colored spine (1-2.5 

 cm. long), which is naked or with 1 to 4 pairs of spinules at the broad base ; 

 corollas purplish, all tubular. — Ballast and waste ground, rarely in open woods 

 near towns, N. Y. to Va. June-Get. (Nat. from Eu.) 



2. C. solstitiAlis L. (Barnaby's Thistle.) Grayish with loose floccose 

 pubescence, branched, 3-5 dm. high ; basal leaves deeply pinnatifld ; the lobes 

 oblong and elliptical, serrate ; cauline leaves small, oblong-lanceolate, entire or 

 nearly so, strongly decurrent in hroadish wings upon the stem; body of the 

 involucre ovoid, 1.5 cm. in diameter, the stout straight stramineous spines 12-18 

 mm. long, widely spreading or reflexed ; flowers yellow. — Waste ground, etc., 

 e. Mass. to Ont. and la., becoming frequent. (Adv. from Eu.) 



3. C. MELiTENsis L. LpMves slightly decurrent ; heads subsessile, or mostly 

 short-peduncled, leafy-bracted at base; middle and lower bracts terminated by 



slender weak divergent spinulose-based spines ; innermost bracts 



with ascending purplish spines ; corollas yellow. — Ballast and 



MMi^ *Tn. "^^ste grounds about ports ; more abundant in the Pacific States. 



June-Sept. (Nat. from Eu.) 



_ 4. C. JlCEA L. Simple or branched, 3-6 dm. high ; leaves 



1010 c Jacea lanceolate or oblanceolate, slightly denticulate, the lowest peti- 



Involu re and' ©led, the upper sessile ; heads showy ; involucre subglobose ; 



bract X V outer bracts pale ; the others glossy dark brown, entire or 



^' slightly lacerated; corollas rose-purple, the marginal conspicvr- 



ously enlarged and falsely radiate. — "Waste ground and 



fields, local, N. E., N. Y., and N. J June-Sept. (Nat. 



from Eu.) Fig. 1010. 



Var. lIcera Koch. Leaves often runcinate-dentate ; 

 outer and middle bracts of the involucre with a pale finely 

 lacerated fringe. Mass, to N.J. (Nat. from Eu.) Fig. 1011. 



5. C. Cyanus L. (Bluebottle, Bachelor's Button, loil. C. Jacea, v. lac. 

 Corn-flower.) Slender, Vf\i\\ long ascending branches ter- involucre and bract 

 minated by solitary heads j involucre ovoid, of about 4 very x i/g- 

 unequal series of pale bracts; the outermost narrowly del- 

 toid, and with the longer middle ones bordered by a white or silvery sharp- 

 toothed scarious band; the innermost elongate-lanceolate, with more or less 

 erose and colored tips ; marginal flowers large and ray-like, blue, violet, pink, 

 or white. — Escaped from cultivation to roadsides, etc. July-Sept. (Introd. 

 from Eu.) 



6. C. ScABi6sA L. Plant rather villous, leafy toward the base, the solitary 

 large (5-6 cm. broad) heads on elongated bracted peduncles ; involucre broadly 

 ovoid; the outer bracts ovate-triangular, the inner oblong, all icith a conspic- 

 uously pectinate-ciliate dark margin ; corollas purplish, the marginal falsely 

 radiate. — Fields and waste places, local, e. Que. to Ont. and 0. (Nat. from Eu.) 



