222 COMPOSITE. [Centaurea. 



25. CENTAURE'A, L. 



Herbs of various habit. Leaves entire or cut, often spinous-toothed. 

 Involucre ovoid or globose ; bracts appressed, imbricate, entire andscarious, 

 or spinous, or dilated fringed or toothed ; receptacle flattish, bristly. 

 Corollas all tubular, oblique or 2-lipped, ventricose above ; outer usually- 

 larger, neuter, inner 2-sexual ; lobes 5, slender. Filaments glandular ; 

 anthers, with a long terminal coriaceous appendage, cells tailed or not. 

 Fruit compressed, basal areole oblique, top broad ; pappus-hairs short, 

 slender, scabrid, usually in many series, inner smaller often scaly, rarely 

 0. — Distrib. Europe, W. Asia, N". Africa, America ; species 320. — Etym. 

 Mythical. 



Section 1. Ja'cea. Invol. bracts with a dilated broad appendage. 



1 . C. ni'gra, L. ; leaves hispidulous lanceolate entire or distantly lobed, 

 peduncles leafy, pappus-scales short unequal or 0. Knapweed. 

 Meadows and pastures, N. to Shetland ; ascends to 1,600 ft. in Northumbld. ; 



Ireland; Channel Islands ; fl. June-Sept.— Perennial. Stem |-3 ft., slender, 

 grooved, simple or branched. Leaves scattered, variable, lower petioled, 

 uppermost quite entire. Heads 1-1| in. diam. ; invol. appendage very 

 variable, pale or dark brown, orbicular, pectiuate on the margin or to the 

 axis. Flowers purple, outer often larger. Fruit grey. — Distrib. W. 

 Europe ; iutrod. in N. America. 

 0. ni'gra proper ; peduncles thickened, appendages of bracts dark brown 

 deeply pectinate.— Var. C. decip'iens, Thuill. (C. nigres'cens, Bab.) ; pedun- 

 cles slender, appendages paler, less deeply pectinate, spines much shorter, 

 pappus 0. — S. counties. 



Section 2. Cy'anus. Invol. bracts not appendaged, their upper part 

 and margins scarious and pectinate or ciliate. 



2. C. Scabio'sa, L. ; erect, leaves deeply pinnatifid segments entire or 

 lobed, peduncles glabrous, involucre globose, bracts with brown pectinate 

 tip and margins, pappus as long as the fruit. Hard-heads. 



Dry pastures and waste places, from Sutherland southd. ; Ireland ; Channel 

 Islands ; fl. July-Sept. — Rootstock woody. Stem 2-3 ft., grooved, sparingly 

 branched, clothed with soft hairs. Leaves 4-10 in., almost pinnate, seg- 

 ments obovate. Heads l|-2 in. diam., rayed ; invol. bracts with a broad 

 brown tip which is decurrent on the sides of the bracts ; flowers bright 

 purple. Fruit grey, pubescent. — Distrib. Europe, Siberia, "W. Asia to 

 Persia. 



3. C Cy'anus, L. ; erect, leaves narrow entire or lobes few spreading, 

 peduncles cottony, involuere ovoid, margins of bracts deeply toothed 

 scarious, pappus shorter than the fruit. Bluebottle, Cornflower. 

 Cornfields, from Caithness southd.; ascending to 1,000 ft. in the Highlands; 



Ireland ; Channel Islands ; (a colonist, Wats.) ; fl. June-Sept.— Annual or 

 biennial. Stem 1-2 ft., slender, grooved, sparingly branched. Leaves 2-4 

 in., variable, sessile, acute, lower |-1 in., upper ^o ^ n - broad. Heads §-1 in. 

 diam., cobwebby ; teeth of bracts triangular, spreading, of outer white, of 



