274 



CENTAUREA 



CEXTAUREA 



high, woolly-white when young : Ivs. linear, entire, or 

 the lower toothed, sometimes pinnatifid : fls. blue, pur- 

 ple or white, the heads on long, naked stems : involu- 

 cral bracts rather narrow, fringed with short, scarious 

 teeth. S. E. Eu. Gt. 38, p. 641 ; 39, p. 537. One of the 

 most popular of garden fls., running into many wirieties. 

 It is perfectly hardy, blooming until frost and coming 

 up in the spring from self-sown seed. The following are 



406. Centaurea Cyanus (X 



varieties of this: Pure White; Victoria, a dwarf, for 

 pots and edgings ; Emperor William, fine dark blue ; 

 flore pleno, with the outer disc fls. converted into ray 

 fls. ; nana compacta, dwarf. 



AAA. SWEET SULTANS. Straight-growing, smooth an- 

 nuals or perennials, with dentate Ivs., grown 

 for the large fragrant heads. 



5. moschata. Linn. (C. suaveolens, Linn. C. odordta, 

 Hort. C. Amberbdi, Mill. Amberbda moschdta, Less.). 

 SWEET SULTAN. Fig. 407. Annual : sts. 2 ft. high, 

 branching below, erect : whole plant smooth, bright 

 green : Ivs. pinnatifid, the lobes dentate : fl. -heads long- 

 peduncled ; in vol. round or ovate, smooth ; only the in- 

 nermost of the invol. scales with scarious margins: fls. 

 white, yellow or purple, fragrant. Orient. Mn. 4: 149. 

 Gn. 54:1195. l.H. 42, p. 106. Gng. 4:147. 



Var. alba, Hort. (C. Margarita, Hort.). Fls. white. 

 Gn. 19, p. 337: 54:1195. A.G. 13: 607. This form, known 



as C. Margarita}, is pure white and very fragrant. It was 

 int. by an Italian firm in 1891. 



Var. rubra, Hort. Fls. red. Gn. 54: 1195. A popular, 

 old-time garden flower, with long-stalked heads ; of easy 

 culture. It does not bear transplanting well. 



C. imperidlis, Hort., is the offspring of C. moschata 

 and C. Margaritce, int. into the American trade in 1899. 

 Plants are said to inherit the vigorous, free growth of 

 C. moschata, being of the same easy culture and forming 

 clumps 3-4 ft. high. The fls. resemble C. Margaritce, but 

 are twice as large and abundantly borne on long stems 

 from July until frost. They range through white, rose, 

 lilac and purple, are fragrant, and if cut when first open, 

 will keep 10 days. C. Mdrice, Hort., int. 1899, resembles 

 C. imperialis, but the fls. open sulfur-yellow, become 

 lighter, and are tipped with rose. 



AAAA. OTHER CENTAUREAS of various kinds, occa- 

 sionally grown in hardy borders for their fls* 

 or imposing stature. 



B. Foliage green on both sides. 

 c. Jjvs. pinnate or bipinnate. 



6. splendens, Linn. (C. margaritdcea, Ten.). Peren- 

 nial : sts. erect, branched : Ivs. smooth, the lowest bi- 

 pinnate, the upper pinnate, all with very narrow, linear, 

 entire, acute lobes : fl. -heads subglobose ; scales of the 

 involucre with a rounded, almost entire, rather lax tip ; 

 fls. purple. Spain, Italy. 



cc. Lvs. entire or dentate, not pinnatisect. 



1. Americana, Nutt. (Plectocephalus Americdnus, 

 Don). BASKET FLOWER. Fig. 408. Hardy annual, nearly 

 smooth : sts. stout, simple, 2-5 ft., thickened under the 

 naked head : Ivs. mostly entire, oblong-lance-shaped : 

 involucre %-l>a in. in diam., its bracts all with fringed, 

 scarious appendages ; fls. rose or flesh-colored ; disc 

 1-3 in. diam. ; narrow lobes of the ray 

 flowers often 1 in. long. Ark. to Ariz. 

 F. S. 4: 327. S. H. 2: 223. -Very attractive. 



8. macrocephala, Puschk. Perennial : 

 stems simple, erect, swollen below the 

 flower-head, leafy, 2^-3 ft. high : Ivs. 

 ovate-lanceolate, slightly decurrent, sca- 

 brous, acute, somewhat serrate, gradually 

 diminishing upwards to the base of the 

 single terminal head : head subglobose, 

 larger than a hen's egg, often 3-4 in. in 

 diam. ; involucre of 8-12 rows of ap- 

 pressed, scarious-margined, rusty, fringed 

 scales : fls. yellow, the marginal and disc 

 alike. Armenia. B. M. 1248. J. H. Ill, 

 33:331. Often grown from seeds. 



9. nigra, Linn. KNAPWEED. HARD 

 HEADS. Perennial, 1-2 ft. high : sts. 

 branching, rough pubescent: Ivs. lance- 

 shaped and entire or lower 



sparingly toothed : invo- 



lucral bracts with pecti- 



nate-ciliate-frdnged black 



appendages: fls. all alike, 



the disc and marginal ones 



of the same size. Europe. 



Var. varieg&ta, Hort. 



Lvs. edged with creamy 



white, tufted. A very strik- 

 ing border plant. 



BB. Foliage white or to- 

 i mentose, at least be- 

 neath (often green 

 above). 



c. Stems low, weak, 

 not strict. 



10. leucophylla,Bieb.(<7. 

 deqlindta, Bieb.). Peren- 

 nial : stems short, decum- 

 bent, with very few Ivs. : 

 root-lvs. petioled, tomen- 



407. Centaurea moschata. 

 CXXO 



tose-woolly on both sides, pinnate, the ovate lobes un- 

 dulate, sparsely cut-lobed or sinuate-toothed : fl.-head 

 with few bracts, solitary, terminal ; scales of the ovate 

 involucre lanceolate, acuminate, brown, long-ciliate : 

 fls. purple. Caucasus. 



