DiPLOPAPPus. COMPOSITE. 351 



long as the corolla ; the exterior very short, setaceous or subulate. — Perennial herbs or 

 suffruticose plants, of various habit, with alternate, mostly entire sessile leaves. Heads 

 corymbose, or terminating the simple branches. Rays blue, purple or white ; the corolla 

 of the disk yellow, rarely turning to purple. 



^ 1. Ianthe, Toxt. & Gr. Bristles of the inner pappus not clai-dlate or thickened at the tip ■ the 

 exterior setaceous : achema villous or silky, linear, somewhat compressed : involucre about the 

 length of the disk: leaves crotvded, linear, rigid, one-nerved, mucronate, with very rowh 

 margins: heads terminating the simple branches. * 



1. DiPLOPAPPus LiNARiiFOLius, Hook. Narrow-kaved Diplopappm. 



Stems strict, usually several from one root, or branching at the base ; leaves linear rigid 

 spreading ; scales of the turbinate involucre rigid, carinately one-nerved, the exterior short 

 and acute, the mterior mostly obtuse ; achenia silky villous. — Hook. jl. Bor -Am 2 p 21 ■ 

 Darlingt. ft. Cest. p. 743 ; Torr. 4. Gr. Jl. N. Am. 2. p. 181. D. linariifolius and vigidus 

 Lmdl. in DC. prodr. 5. p. 277. Diplostephium linariifolium, Nees, Ast.p. 199. Chrysopsis 

 hnarufolia, Nutt. gen. 2. p. 152. Aster linariifolius, Linn. sp. 2. p. 874 ; Micha: Jl 2 p 

 110 ; Pursh, Jl. 2. p. 545 ; Ell. «A. 2. p. 365 ; Bigel. fl. Bost. p. 309 ; Beck, hot. p. 187 

 A. rigidus, Lmn. I. c. ; Michx. I. c. ; Pursh, I. c. A. pulchcrrimus, Lodd. hot. cab. \.t.6. 

 Stems 8-18 inches high, growing in clusters, erect or assurgent, reddish, puberulent, the 

 lower part either simple or divided near the root, with very few or numerous corymbose 

 branches at the summit ; the peduncles or flowering branches usually somewhat elongated 

 (often with small bract-like leaves), or frequently short and in a compact cluster. Leaves 

 about an inch long and a line wide, crowded, sometimes refie.xed, the margin very rough with 

 minute prickles. Heads large and showy. Scales of the involucre ciliate, finally^ little 

 spreading; the inner ones purplish at the tip. Rays 10 - 12, violet, twice as long as the 

 involucre. Exterior pappus copious. Achenia small. 



Dry open woods and on hill-sides ; common. August - October. A humble but ornamentaJ 

 species. 



^ 2. Triplopappus, Torr. & Or. Bristles of the inner pappus unequal, some of them clavellate or 

 thickened at the summit, the exterior of somewhat scale-like bristles : achenia obovoid, compressed, 

 smooth or slightly pubescent, 5 - Q-nerved : involucre shorter than the disk : leaves lanceolate, 

 ovate or oblong : rays white. 



2. DiPLOPAPPus coRNiFOLius, Darlingt. Cornel-leaved Diplopappus. 



Stem slender, roughish-pubescent, rather naked and sparingly corymbose-paniculate at the 



summit ; leaves elliptical, acuminate at each end, hairy on the veins underneath ; heads few, 



on divaricate pedicels ; achenia amoolh.— Darlingt. Jl. Ccst. p. 474 ; Torr. cj- Gr.Jl. N. Am'. 



2. p. 182. DffiUingeria cornifolia, Nees, Ast. p. 181. Diplostephium cornifolium, DC. prodr. 



