COMPOSITE. 473 



deeply cleft into 5 long and narrow lobes; the marginal in some enlarged 

 and palmatifid but never ligulate. Stamens syngenesious and also 

 rarely monadelpbous below. Anthers caudate. Style slightly or not at 

 all cleft, commouly with a pubescent node or ring below the stigmatic 

 part. Achenes thick, hard, smooth, basally or obliquely inserted. 

 Pappus setose, plumobe, or rarely paleaceous, sometimes wanting. 



Hiiitis of tlie (jieiiera. 



* Receptacle setose. 



Pappus of many setose bristles; 



Ray-Howere enlarged, palmate, - _.-»., jq^ 



" " not enlarged, ---------. Iqj 



Pappus double, of 2 different sets; 



Both sets brietly, -------.. jog 



" ■' paleaceous, --.•--_. J09 



Pappus of many series of narrow barbellate paleae, .---.. jjO 

 Pappus united at base, deciduous in a ring; 



In many series of plumose bristles, ---.-... m 



In one series of plumose bristles, -------- ng 



* * Receptacle paleaceous. 

 Pappus of few unequal paleae, -.----...., j^g 



lOG. CYAN US, Tournefort. Anniial flocculently hoary unarmed 

 herbs. Heads naked, in slender peduncles. Bracts of the ovate invo- 

 lucre narrow, fringed with scarious teeth. Marginal corollas much 

 larger than the others, palmatifid and raylike. Pappus of unequal 

 bristles, the longest about as long as the achenes. 



1. 0. SEGETUM, Buchoz, Dict i. 197 (1770). Cenlaurea Cyanus, Linn. 

 Sp. PI. ii. 911 (1753). (Cornflower.) Slender, 1—2 ft. high, not 

 prickly, whitened, at least when young, with floccose wool: leaves linear, 

 entire, or the lower toothed or pinnatifid: heads naked, on slender 

 peduncles: involucral bracts narrow, fringed with short scarious teeth: 

 marginal flowers asexual, much enlarged, irregularly and somewhat 

 palmately cleft and ray-like, blue or pinkish or white: pappus of unequal 

 bristles about equaling the achene. — Escaped from gardens to waysides; 

 also occasional in grain fields; everywhere admired for the beauty of its 

 flowers, 



107, CENTAUREA, Linnsens. Annual or biennial herbs of various 

 habit. Leaves lanarmed and decurrent, or spinescent and merely sessile. 

 Heads ovate; the imbricated bracts ending in a stout spine. Achenes 

 compressed or somewhat tetragonal, the insertion somewhat oblique or 

 sublateral. Pappus of many slender scabrous bristles, mostly in two 

 sets, or wanting. — All our species naturalized from Europe. 



