ORDER 70. COMPOSITE. 421 



1. BIOTIA, DC. COBTMBED ASTERS. 



1 A. corymbosuB Ait. St. corymbous-fastigiate, nearly smooth, branches pu- 

 bescent ; Ivs. thin, ovate-acuminate, serrate, with sharp spreading teeth, the lower 

 cordate, peliolate, the petioles wingless ; invol, oblong, 6 to 9-rayed, imbricate 

 with close-pressed, acute scales. Common in dry woods, N. and Mid. States. 

 St. 2f high, often reddish, more or less flexuous. Lvs. large, mostly smooth, tho 

 upper becoming lanceolate, sessile. Hds. 4" long, in a broad, flat, open corymb, 

 with about 6 oblong, white or roseate rays. Aug. (Eurybia corymbosa Cass.) 



2 A. macrophyllus Willd. St. rough-pubescent, widely branched ; Ivs. ovate, 

 petiolate, serrate wfth short, depressed teeth, rough, the upper ovate-lanceolate, 

 sessile, lower cordate, petiolate, petioles somewhat winged ; invol. cylindric, closely 

 imbricate with oblong, acute scales; rays 8 to 15. Woods N. States and Can. 

 St furrowed, 1 to 21' high. Lvs. often very large (6 to 10' by 3 to 6''). Rays 

 white or pale blue. Hds. 6" long. Sept. (Eurybia corymbosa Cass.) 



2. CALLIASTRTTM, Torr. & Gr. VIOLET-FLOWERED ASTERS. 



3 A. mirabilis Torr. & Gr. Scabrous, simple below; Ivs. ovate, serrate, the 

 lowest petiolate, the others sessile, tJtose of the brandies roundish, small ; invol. 

 hemispherical, shorter than the disk, scales imbricated, in 4 or 5 series succes- 

 sively shorter, with obtuse, green, recurved tips ; rays about 20. Columbia, S. Car. 

 (Prof! Gibbs in N. Am. Flora II., 1G5). Wo have not met with this species. 



4 A. radula Ait. Erect, simple below, angular; Ivs. lanceolate, acuminate, nar- 

 rowed to the sessile base, sharply serrate, rugous and rough ; invol. imbricate, 

 squarrous with the short spreading green tips of the scales. Moist groves and 

 hedges, Me. to Penn. Height 1 to 3f, remarkable for its straight, smooth stem, 

 stiff, sharply serrate Ivs. Branches nearly leafless, simple, each bearing a single 

 large head, rarely more, with 20 pale violet rays spreading 1$'. Aug., Sept. 



5 A. spectabilis Ait. Erect, rough-puberulent above; Ivs. roughish, oblong- 

 lanceolate, sessile, entire, the lower obscurely serrate ; branches corymbed ; invol. 

 hemispherical, with squarrous, spreading, ciliate scales. A low, handsome Aster, 

 of pine barrens, Mass, to N. J. and Ky. St. 1 to 2f high, branching above into a 

 nearly simple corymb of 10 15 large and showy heads, each with about 20 long 

 violet blue rays. Sept. Nov. 



6 A. surculdsus MX. Sts. arising from a knotted creeping rhizome, low, slender, 

 simple or corymbous at top; Ivs. linear-lanceolate, entire or subserrate, upper 

 linear, clasping ; hds. 1 to 5 ; scales linear-oblong, ciliate, inner obtuse, outer with 

 green spreading tips; rays about 20. Wet pino barrens, N. J. to IT. Car. and 

 Tenn. Sts. smoothish, 12 to 18' high. lit. -Ivs. spatulate, 4 to 6' long. Hds. 

 large, obconic, witli violet-purple rays. Sept. 



/3. GRACILIS Gray. Hds. smaller and more numerous (8 to 12), with the invol- 

 ucre more close, and the rays about 12 (A. gracilis Nutt). 



7 A paludosus L. Slender, glabrous ; Ivs. long, linear, rigid, margins scarcely 

 rough, clasping at base; hds. 1 to 6, hemispherical; scales green, lance-linear, 

 somewhat spreading; rays about 30, longer than the (6'') involucre. Swamps in 

 pine barrens, N. Car. to Fla. and La. Sts. 2 to 3f high. Hds. very large, with 

 violet-blue rays spreading 1 J to 2'. Pappus tawny. Aug. Oct. 



3. ASTER proper. PANICLED ASTERS. 



8 A cordifolius L. St. paniculate, smoothish; lower Ivs. cordate, hairy 

 beneath, sharply serrate, acuminate, petiolate; petioles winged; invol. closely 

 imbricate, the scales with short, green tips. Common in rocky woods, N. and W. 

 States. Stem with a handsome panicle of racemes at top of numerous, rather 

 small flowers. Rays 1015, pale blue varying to white. Lower leaves large. 

 Petioles more or less winged, hairy. Above, the leaves are gradually reduced 

 to small or minute bracts. Sept. 



9 A. sagittifoliua Willd. ARROW-LEAVED ASTER. St. with racemous branches 

 above, smooth ; Ivs. oblong-lanceolate, acuminate, sessile t serrate in the middle, 

 radical ones ovate, oblong, cordate-sagittate, serrate, petiolate; invol. loosely 

 imbricate, scales linear-subulate. Low woods, N. and W. States and Can. Stem 



