198 COMPOSITA. (COMPOSITE FAMILY.) 
3. S. tortifolius, Nees. Closely pubescent; leaves short, obovate, rarely 
serrate, vertical; involucre top-shaped ; the scales oblong and slightly spreading 
at the tips; pappus copious, white. (Aster tortifolius, Michz.) — Sandy pine 
barrens, Florida to North Carolina, and westward. August. — Stem 19-29 
high. Leaves 1’ long. 
16. ASTER, Tourn. ASTER. SrARWORT. 
Heads many-flowered ; the rays (white, blue, or purple) in a single series, pis- 
tillare. Scales of the involucre more or less imbricated, mostly with herbaceous 
or leafy tips. Receptacle flat, pitted. Achenia usually compressed. Pappus à 
single row of numerous rough capillary bristles. — Perennial (rarely annual) 
herbs. Leaves alternate. Disk-flowers yellow, often changing to purple. 
$1. Brorra.— Involucre obovate-bell-shaped ; the scales (pale) closely imbricated, 
and nearly destitute of herbaceous tips: achenia somewhat 3-angled : bristles of the 
pappus rigid : leaves large; the lower ones cordate: heads corymbed. 
1. A. corymbosus, Ait. Stem slender, smooth; leaves on slender peti- 
oles, thin, coarsely serrate, acuminate ; the lower ones cordate, the upper oblong; 
involucre shorter than the disk, the scales obtuse; rays 6 —9, white. — Shady 
woods in the upper districts, Georgia and northward. Sept. and Oct. — Stem 
19-2? high. Leaves 2'-4'long. Corymbs loose. 
2. A. macrophyllus, L. Stem stout, rough-pubescent ; leaves large, 
rather thick, rough, mucronate-serrate, acute; the lowest broadly cordate, om 
slender naked petioles; the upper ovate, on short and winged petioles; invo- 
luere nearly as long as the disk ; the exterior scales rigid, with spreading fringed 
tips; rays about 10, pale purple. — Low shady woods, in the upper districts of 
Georgia, and along the mountains, northward. Sept. — Stem 119-29 high. 
Leaves 4! — 6/ long, 2/ — 4! wide. 
$2. CaLLIASTRUM. — Scales of the involucre imbricated in several rows, coriaceous, 
usually with herbaceous spreading tips: rays 12 or more: achenia nearly smooth : 
pappus of unequal rather rigid bristles, somewhat thickened upward : leaves rigid, 
none of them cordate : heads large and showy. 
3. A. mirabilis, Torr. & Gray. Rough-pubescent; stem corymbosely 
branched above; leaves ovate, mucronate-serrate, sessile; the lowest abruptly 
narrowed into a petiole; involucre hemispherical; the scales oblong-linear, ob- . e 
tuse and recurved at the summit; achenia nearly smooth, striate. — Columbia, 
South Carolina, Prof. (ribbes. Sept. — Stem 19 — 29 high. — Stem-leaves te 
