COMPOSITA. (COMPOSITE FAMILY.) 207 
bristles in two rows, the outer row much shorter. — Perennial erect herbs. 
Leaves alternate. Heads single or corymbose. Rays white or purple. 
* Rays purple. 
1. D. linariifolius, Hook. Stem rigid, simple, closely pubescent; leaves 
numerous, linear, spreading, the margins very rough ; heads solitary or some- 
what racemose ; scales of the involucre imbricated in several rows, linear, ap- 
pressed ; achenia silky. — Dry open woods, West Florida to Mississippi, and 
northward. September.— Stem 1° high. Leaves 1/ long. 
* * Rays white. 
2. D. cornifolius, Darl. Stem pubescent ; leaves elliptical, tapering at 
each end, hairy on the margins and veins beneath ; heads few, on slender 
spreading peduncles ; achenia smooth. — Upper districts of Carolina, and north- 
ward. August. — Stem 1°-2° high. Leaves 2'— 4! long. zd , 
3. D. amygdalinus, Tor. & Gray. Stem roughish and corymbose 
above ; leaves oval or oblong, acute at each end, nearly smooth ; heads numer- 
ous, corymbed ; scales of the involucre obtuse; achenia hairy. — Swamps, Flor- 
ida, and northward. September. — Stem 29 - 49 high; the branches spreading. 
Leaves 11! — 9! long. 
^ D. umbellatus, Tor. & Gray. Stem smooth, corymbose above ; 
leaves lanceolate, acuminate; scales of the involucre acutish ; achenia hairy. — 
Swamps in the upper districts. September. — Stem 3°-6° high. Branches 
erect. Leaves 3/—5! long. i ui p e E 
5. D. obovatus, Torr. & Gray. Closely pubescent; stem simple, scaly 
at the base ; leaves oblong, sessile, strongly veined ; heads large, corymbed, on 
long and naked (whitish) peduncles ; scales of the involucre acute ; achenia 
hairy. (Aster obovatus and A. dichotomus, Ell.) — Low pine barrens, Florida 
fo South Carolina. May - July. — Stem 19 - 2 high. Leaves 1/—2! long. 
19. BOLTONIA, L'Her. 
: Heads many-flowered. Rays pistillate. Scales of the hemispherical involucre 
imbrieated in two rows, not longer than the disk. Receptacle hemispherical or 
conical, obscurely alveolate. Achenia flattened, obovate, wing-margined. Pap- 
Pus composed of several short chaffy scales; that of the disk-flowers mostly - 
with 2—4 longer awns. — Perennial herbs, resembling Asters. — — oo 
1. B. diffusa, Ell. Stem with long and slender branches ; leaves linear, 
entire; heads small, terminal ; achenia narrowly margined, hairy ; pappus very 
short, 2-awned. — Damp soil, Florida to North Carolina, and westward. Sept. 
and Oct. — Stem 3°-4° high. Rays purplish. : Wh 
2 B. Blastifolia, L'Her Stem paniculate ; leaves rigid, lanceolate, - 
;Paringly serrate ; the upper ones linear, entire; heads rather large ; achenia 
_ broadly margined ; pappus of few short bristles, and 2-4 long awns.— 
S, Florida, and northward. July - Sept. — Stem 3° - 
gets 
