860 



COMPOSITAB (composite FAMILY_) 



Some bracts with regularly pectinate or toothed inargrin or tip. 

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

 late leaves 6. G. Cyarmt. 



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

 usually pinnatifid or coarsely toothed. 

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

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

 spicuous, their margins dark 6. (7. Scabiosa. 



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

 bodies of the involucral bracts mostly hidden by the imbricated 

 appendages. 

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

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



appendages 8. O. americana^ 



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

 Lower leaves pinnatifid into linear or lanceolate segments, the upper 



mostly linear ; involucral bracts distinctly ribbed . . . . 9. (7. maculosa. 

 Lower leaves elliptic or oblanceolate, lyrate-pinnatifid or coarsely 

 dentate, the upper similar ; involucral bracts plane or obscurely 

 ribbed 10. C, nochmensis. 



1. C. CALCfTRAPA 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-Oct. (Nat. from Eu.) 



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

 pubescence, branched, 8-5 dm. high ; basal leaves deeply pinnatifid ; the lobes 

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

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

 involucre ovoid, 1.5 cm. in diameter, the stout straight stramineous spinesl2-18 

 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. Leaves slightly decurrent ; heads subsessile, or mostly 

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



slender weak divergent spinulose-hased spines ; innermost bracts 

 with ascending purplish spines ; corollas yellow. — Ballast and 

 waste grounds about ports ; more abundant in the Pacific States. 

 June-Sept. (Nat. from Eu.) 



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

 1010 Jacoa lanceolate or oblanceolate, slightly denticulate, the lowest peti- 

 Involucre anil °'®'^' *''® 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 conspicu- 

 ously enlarged and falsely radiate. — Waste ground and 

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

 from Eu.) Fig. 1010. 



Var. lAceua 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. CVanus L. (Bluebottle, Bachelor's Button, loil. 0. Jacea, v. Ian. 

 CoRN-FLOvi'ER.) Slender, with long ascending branches ter- Involucre and bract 

 minated by solitary heads ; involucre ovoid, of about 4 very x %. 

 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. ScABibSA 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 with 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.) 



