COMPOSIT.^. (composite FAMILY.) 217 



Tribe III. ASTEROIDE^. Heads discoid or radiate : the rays pistillate : 

 branches of the style, in the perfect flower , flattened , linear or lanceolate, equally 

 pubescent above on the outside : the conspicuous stigmatic lines terminating where 

 the exterior pubescence commences. 



15. SERICOCARPUS, Nees. 



Heads 12-15-floMered; the ray flowers about 5. Aviiite, pistillate; those of 

 the disk tubular and perfect. Involucre somewhat cyliudrical or club-shaped ; 

 the scales cartilaginous, whitish, closely imbricated in several rows, with green- 

 ish and more or less spreading tips. Keceptacle pitted, toothed. Achenia 

 short, obpyramidal, silky. Pappus simple, composed of numerous capillary 

 bristles. — Perennial herbs. Leaves alternate. Heads crowded in a dense 

 corymb. Disk flowers yellow. 



1. S. conyzoides, Nees. Stem slightly pubescent, corymbose above; 

 nearly terete ; leaves ciliate on the margins, otherwise smooth, the lower ones 

 spatulate-oblong, serrate al)ove the middle, the upper oblong or lanceolate and 

 entire ; involucre top-shaped ; pappus rust-color. — Dry gravelly or sandy soil, 

 in the middle and upper districts. August. — Stem l°-2° high. 



2. S. solidagineus, Nees. Smooth; stem angled; leaves lanceolate 

 or linear, obtuse, entire, the lowest spatulate ; involucre top-shaped ; pappus 

 white. — Low ground in the upper districts. August. — Stem slender, 2° 

 high. Heads smaller than in the last. 



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. — Sandy pine barrens, iu the 

 middle and lower districts. 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, 

 pistillate. Scales of the involucre more or less imbricated, mostlv with her- 

 baceous 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 chan- 

 ging to purple. 



§1. BiOTiA. — /ni'o/Mc;-e obovate-bel I- shaped : the scales (pale) closely imbri- 

 cated, 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 

 petioles, tliin, coarsely serrate, acuminate ; the lower ones cordate, the upper 

 oblong; involucre shorter than the disk, the scales obtu.se; rays 6-9, white. 

 — Shady woods in the upper districts. Sept. - Oct. — Stem l°-2° high. 

 Leaves 2' -4' long. Corymljs loose. 



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

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

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



