COMPOSIT.E. (composite FAMILY.) 219 



scurely crenate and narrowed into a petiole; heads corymbose; involucre 

 (whitish) obconical, as long as the disk ; tlie scales very uuecjual, acute, the 

 lower ones much shorter, green and slightly spreading at the tips. — North 

 Carolina and Tennessee. Sept. — Stem l°-2° high. Leaves l'-2' long. 

 Heads smallest of this group. Rays about 12, violet. 



9. A. SUrculOSUS, Michx. Stems several from a creeping caudex, slen- 

 der, pubescent above ; leaves lanceolate or linear-lanceolate, acute, smooth, the 

 margins rough and sometimes sparingly serrate, clasping; the lowest nar- 

 rowed iuto^a petiole; heads solitary, or 3-5 in a simple corymb; involucre 

 broadly top-shaped, nearly as long as the disk; the scales linear-spatulate, 

 with abruptly pointed spreading herbaceous tips ; the outer ones lanceolate 

 and leaf-like. — Low ground, Georgia to North Carolina. Sept. — Stem |°- 

 1|° high. Lowest leaves 4' - 6' long. Heads ^' wide. Eay s numerous, violet. 



10. A. Curtisii, Torr. & Gray. Smooth throughout ; stem simple, slen- 

 der ; leaves membranaceous, lanceolate, entire or slightly serrate, acuminate, 

 sessile ; heads in a simple or slightly compound terminal raceme ; scales of the 

 involucre linear-spatulate, coriaceous, the green and spreading tips barely 

 acute; rays purple. — Mountains of North Carolina. — Stem 2° -3° high. 

 Leaves 3' - 4' long. Heads i' - f in diameter. 



§ 4. Aster proper. — Scales of the involucre imbricated in various degrees, 

 with herbaceous tips : rays numerous : achenia flattened : pappus of soft cap- 

 illary bristles, not thickened upward : autumnal plants. 



* 1. Leaves uniform, small, sessile, entire, silky or silvery on both sides, mucro- 

 nate: scales of the involucre imbricated in 3 -several rows: rays violet-purple. 



11. A. sericeus, Vent. Stem with numerous branches, bearing the 

 large heads (single or 3 in a cluster) at their summits; leaves oblong-lanceo- 

 late, silvery ; scales of the involucre leafy and spreading ; achenia smooth. — 

 A western species, a form of which, with narrower and less silvery leaves and 

 scales, occurs on the mountains of Georgia and Tennessee. — Stem 10' -20' 

 high. Leaves I'- I' long. Heads showy. ' 



12. A. COncolor, L. Stem mostly simple, slender, bearing towards the 

 summit, the middle-sized heads in a long often compound raceme ; leaves 

 lanceolate, silky wiien young ; the lowest ones oblong ; scales of the obovoid 

 involucre lanceolate, ajipressed, the subulate tips spreading ; achenia silky. — 

 Dry sandy soil, Florida, and northward. — Root sometimes tuberous. Stem 

 l°-3° high. Leaves erect, Y-V long. 



* 2. Leaves rough, all sessile or clasping and entire: heads chiefly solitarij, ter- 



minating the branchlets : scales of the obovoid or bell-shaped involucre imbri- 

 cated in several rows, coriaceous, with herbaceous slightly spreading tips : 

 rays purplish blue : achenia hairy. 

 +- Leaves very small, sessile: heads small: scales of the involucre spatulate. 



13. A. squarroSUS, Walt. Stem slender, diffuse; leaves oblong or 

 triangular-ovate, reflexed, very rough, sessile ; the lowest spatulate. — Dry 

 .soil, Florida to North Carolina. — Stem l°-2° high. Lowest leaves ^' long, 

 the others 2" - 3" long. 



