466 OaDEit. 10.— COMPOSITiE. 



cules.) Heads diseoid ; involucre imbricate ; ray flowers longer than 

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

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

 alternate Ivs. 



* Bcnles of the involucre with a fringed or pectinate appendage Nos. 1, 2 



* Scales of the involucre merely ciliate, or tipped with a spine Nos. 8, 4 



1 C. nigra L. St erect, branched, pubescent above ; lower Ivs. angular-lyrate, 

 upper lanceolate, dentate, scales ovate, with an erect, capUlary, fringed appendage ; 

 ray and disk-fls. alike. — 11 A troublesome weed, in meadows and pastures, Mass. 

 St. about 2f high, simple, or oftener divided into elongated branches. Hds. few, 

 large, terminal, solitary. Fringed appendage of the scales dark brown. Pla. pur- 

 ple. Jl., Aug. § Eur. 



2 C Americana Nutt. St erect, sulcate, sparingly branched ; lower Ivs. oblong- 

 ovate, repand-dentate, upper ones lanceolate, acute, all sessile and glabrous ; hds. 

 few or solitary, very large ; ped. thickened at summit ; ray fls. twice longer than 

 the dish; scales with a pectinate-pinnate, reflexed appendage. — (J) Ark. and La., 

 naturalized in 111. (Mead.) Cultivated in gardens. St 2 to 4f high, with large, 

 showy, pale-purple hds. Appendages straw-color, f 



3 C. Cyanus L. Bacheloe's-euttok. St. erect, branching, downy ; Ivs. linear, 

 entire, downy, the lowest subdentate ; scales cHiaie-serrate ; ray flowers mucheri- 



, larged. — (D Cultivated and sparingly naturalized in old fields. It is a hardy an- 

 nual, justly popular for its handsome flowers which are very variable in color. 

 Hds, ovoid, solitary on the ends of the branches. Jl. — Sept § Eur. 



4 C. Calcitrapa L. Star Thistle. St diffusely branched, hairy; Ivs. sessile, 

 pinnately lobed, lobes linear, toothed, upper mostly entire ; hds. sessile ; middle 

 scales tipped with a strong, spreading spine with 1 or 2 minute spines each side ; 

 pappus 0. — 3) © Ta. Pis. purple. § Eur. 



92. AMBER'BOA, DC. Sweet Sultan. Heads discoid ; involucre 

 imbricated ; ray-flowors wanting or larger than the rest, steri.e; pappus 

 of oblong or obovato pales, attenuated to the base, all similar, rarely 

 small or 0. — Eastern herbs with alternate Ivs. 



1 A. mosohata "Willd. Ivs. lyrate-dentate ; invol. subglobons, smooth ; 

 scales ovate ; ray-flowers scarcely enlarged, not exceeding the disk ; pappus 0. — 

 A handsome border annual from Persia. Flowers purple. A variety has white 

 flowers. July — Oct (Centaurea L.) f 



2 A. odorata, a. amboracea. DC. Yellow Sweet Sttltan. Lower Ivs. 

 broadly subspatulate, dentate, upper lyrate at base ; hds. globous ; ray-fls. en- 

 larged upwards, longer than the disk ; pappus chaffy, a litSe shorter than the 

 fruit — ^From Levant. Leaves scarcely pinnatifid. Flowers yellow, f (Centaurea 

 suaveolens Willd.) 



j8. glauca. Lvs. often deeply pinnatifid ; flowers purple. ■)■ (Centaurea glauca 

 Willd.) 



93. CAR'THAMUS, L. Saffron. (Arabic, qorthom, to paint ; from 

 •its coloring property.) Heads discoid; involucre imbricated, outer 



bracts foliaceous ; flowers all tubular and ^ , filaments smooth ; pappus 

 ; receptacle with setaceous pales ; achenia 4-angled. — Oriental herbs. 

 C. tinctorius L. St. smooth ; lvs. ovate-lanceolate, sessile, spinous-dentieu- 

 late. — ® Native of Egypt, but. long cultivated in other lands on account of its 

 orange-colored flowers. Stem branching, striate, 1 — 2f high. Leaves subam- 

 plexicaul, smooth and shining. Heads large, terminal, with numerous long and 

 slender flowers. The latter are useful in coloring, and as a nursery medicine. 

 July, f 



94. CNrCUS, Vaill. Blessed Thistle. (Gr. Kvi^u, to prick ; well 

 applied to these herbs.) Heads discoid ; involucre vcntricous, imbri- 

 cate with doubly spinous scales ; ray-flowers sterile ; receptacle very 



