198 COMPOSITE:. (COMPOSITE FAMILY.) 



3. S. tortifolius, Necs. Closely pubescent ; leaves short, obovate, rarely 



sen-ate, vertical ; involucre top-shaped ; the scales oblong and slightly spreading 



at the tips; pappus copious, white. (Aster tortifolius, Miclix.) Sandy pine 



barrens, Florida to North Carolina, and westward. August. Stem l-2 



high. Leaves 1 ' long. 



16. ASTER, Tourn. ASTER. STARWORT. 



Heads many-flowered ; the rays (white, blue, or purple) in a single series, pis- 

 tillate. Scales of the involucre more or less imbricated, mostly with herbaceous 

 or leafy tips. Receptacle flat, pitted. Achenia usually compressed. Pappus a 

 single row of numerous rough capillary bristles. Perennial (rarely annual) 

 herbs. Leaves alternate. Disk-flowers yellow, often changing to purple. 

 1. ISiOTiA. Involucre oltovate-bell-shaped ; the scales (pale) closely imbricated, 

 and nearly destitute of herbaceous tips : achenia somewhat 3-<iyled : bristles of the 

 )xippus rigid : haves 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 

 10 _ oo high. Leaves 2' T 4' long. Corymbs loose. 



2. A. macrophyllus, L. Stem stout, rough-pubescent ; leaves large, 

 rather thick, rough, mucronate-serrate, acute ; the lowest broadly cordate, on 

 slender ntfced petioles; the upper ovate, on short and winged petioles; invo- 

 lucre nearlv 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 l-2 high. 

 Leaves 4' -6' long, 2' -4' wide. 



2. CALLIASTRUM. Scales of the involucre imbricated in several rows, coriaceous, 

 usually with herltaceous 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- 

 tuse and recurved at the summit; achenia nearly smooth, striate. Columbia, 

 South Carolina, Prof. Gibbes. Sept. Stem 1 - 2 high. Stem-leaves 1 ' - 3' 

 long. Rays about 20, blue or violet, elongated. 



4. A. spectabilis, Ait. Stem corymbose and glandular-pubescent above ; 

 leaves oblong-lanceolate, rough on the upper surface, sessile and entire; the 

 lowest tapering into a petiole, and sparingly serrate ; heads not numerous, single, 

 terminating the branches ; involucre nearly hemispherical, as long as the disk ; 

 the scales linear-oblong, with obtuse and spreading glandular tips. (A. surcu- 

 losus ? Ell., with obovate-oblong, mostly serrate leaves, and broader scales of the 

 involucre.) Pine barrens, Florida and northward. Sept. and Oct. Rhizonm 

 slender. Stem 1- 2 high. Leaves 2' -4' long. Heads ' in diameter. Rays 

 about 20, 1 ' long, deep violet. 



