860 



COMPOS1TAE (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. C. Oyanus. 



Biennials 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 . ..... 0. ('. Sca-Moxa. 



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 . 7. C. nigra. 

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



appendages ........... 8. C. aniericana. 



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. C. macwlom. 



Lower leaves elliptic or oblanceolate, ly rate-pin natifid or coarsely 

 dentate, the upper similar ; involucral bracts plane or obscurely 

 ribbed ............ 10. C. vochinensi*. 



1. C. CALCfrRAPA 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. SOLSTITIXLIS L. (BARNABY'S THISTLE.) Grayish with loose floccose 

 pubescence, branched, 3-5 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 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. Leaves 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 

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

 June-Sept. (Nat. from Eu.) 



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

 lanceolate or oblanceolate, slightly denticulate, the lowest peti- 

 olcd, the upper sessile ; heads showy ; involucre subglobose ; 

 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. June-Sept. (Nat. 

 from Eu.) FIG. 1010. 



Var. LACERA 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. CVANL-s L. (BLUKBOTTLE, BACHELOR'S BUTTOX, 1011. C 

 CORN-FLOWER.) Slender, with long ascending branches te-r- 

 initiated by solitary heads; involucre ovoid, of about 4 r */>/ 

 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 /<//>/< <ni<l 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 (6-6 cm. broad} heads on elongated bracted peduncles ; involucre broadly 

 ovoid ; the outer bracts ovate-triangular, the inner oblong, all with a con*i>ir- 

 uously )<<( iitnti'-ciliate dark margin; corollas ;>//*;/ /*/, the marginal fiilm-ly 

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



1010. C. Jacea. 



Involucre and 



bract x %. 



v. i:u-. 

 Involucre and bract 



