354 LXXV. COMPOSITiE. Carthamus. 



receptacle naked ; achenia of the disk membranaceous ; pappus 0. — 

 An oriental genus of annual herbs. Lvs. alternate. 



C. OFFICINALIS. Pot Marigold. — Viscid-pubescent; 5^. erect, branched; lvs. 

 oblong, acute, mucronate, sessile, subdentate and scabrous-ciliate on the mar- 

 gin ; hds. terminal, solitary ; ach. carinate, muricate, incurved. — A common 

 and handsome garden plant, from S. Europe. It has double, lemon-colored, and 

 other varieties. Flowers large and brilliant, generally orange-colored. Jn. — Sept.-j- 



62. CENTAUREA. 



The centaur Chiron, it is said, cured with these his foot wounded by Hercules. 



Heads discoid ; involucre imbricate ; ray flowers larger than the 

 rest, sterile, often wanting ; receptacle bristly ; pappus of filiform, 

 scabrous bristles in several series. — A genus of oriental herbs^ with al- 

 ternate leaves. 



1. C. NIGRA. Black Knapweed. 



St. erect, branched, pubescent above ; loiocr lvs. angular-lyrate, upper lan- 

 ceolate, dentate ; scaks of the involucre ovate, with an erect, capillary fringe. — 

 % A troublesome weed in meadows and pastures, Mass. Introduced from Eu- 

 rope. Stem about 2f high, simple or oftener divided into elongated branches. 

 Heads few, large, terminal, solitary. Scales dark brown. Flowers purple. 

 Jl. Aug. ^ 



2. C. Cyanus. Blue-bottle. Bachelor's-button. 



St. erect, branching, downy ; lvs. linear, entire, downy, the lowest subden- 

 tate ; invol. scales serrate. — (1) liitroduced from Europe, cultivated and sparingly 

 naturalized in old fields. It is a hardy annual, justly popular for its handsome 

 flowers, which are very variable in color. Heads ovoid, solitary on the ends 

 of the branches. Jl. — Sept. ^ 



3. C. Americana. Nutt. (C. Nuttallii. Spreng.) 



St. erect, sulcate, sparingly branched; lower lvs. oblong-ovate, repand-den- 

 tate, upper ones lanceolate, acute, all sessile and glabrous ; hds. few or solitary, 

 very large ; ped. thickened at summit ; invol. depressed-globose, scales with a 

 pectinate-pinnate, reflexed appendage. — (1) Native in Ark. and La., naturalized 

 in 111. Mead. Cultivated in gardens. Stem 2 — 4f high, with ver}' showy, pale- 

 purple heads. ^ f 



63. AMBERBOA. DC. 

 Heads discoid ; involucre imbricate ; ray-flowers wanting or larger 

 than the rest, sterile ; pappus of oblong or obovate paleae, attenuated 

 to the base, all similar, rarely smalFor 0. — Eastern herbs, with alter- 

 iwie leaves. 



1. A. MOscH.lTA. Willd. (Centaurea. Linn.) Sweet Sultan. — Lvs. l_\Tate- 

 dentate ; iyivol. subglobose, smooth ; scaks ovate ; ray-flmvcrs scarcely enlarged, 

 not exceeding the disk ; pappus 0. — A handsome border annual from Persia. 

 Flowers purple. A variety has white flowers. July — Oct. 



2. A, onoRATA. a. amboracca. DC. (Centaurea suaveolens. Willd.) Yellmo 

 Sweet SMan. — Z^w^er Zrs. broadly siibspatulate, dentate, upper lyrate at base; 

 hds. globose ; ray-Jls. enlarged upwards, longer than the disk; pappus chafTv, a 

 little shorter than the fruit. — FYom Levant. Leaves scarcely pinnatifid. Flow- 

 ers yellow. 



0. gl/iHca. (Centaurea glauca. Willd-) Lvs. often deeply pinnatifid ; Jlowers 

 purple. 



64. CARTHAMUS. 



Arabic qorthom, to paint; from its coloring property. 



Heads discoid ; involucre imbricated, outer bracts foliaceous ; 

 flowers all tubular and 5 ., filaments smooth ; pappus ; receptacle 

 with setaceous paleae ; achenia 4-anglcd. — Orieiital herbs. 



