COMPOSITE. 185 



oblong, acute, clasping, cordate, serrate, smooth ; scales of the invo- 

 lucre lanceolate, closely imbricate. A. pennsylvanictis Lam. 



HAB. Woods. N. r J. to Car. Sept. Nov. It. Stem 23 

 feet high. Lower leaves attenuate and clasping, the upper ones 

 more cordate. Flowers in a terminaFpanicle, middle-sized, blue. 



29. A. jtrenanthoides IVilld. : branches hairy ', leaves clasping, spath- 

 ulate-lanceolate, acuminate, serrate in the middle, cordate at base ; 

 scales of the involucre lanceolate, squarrose. 



HAB. Penn. Muhl. Aug. Oct. If. Flowers blue. 



30. A. Icevigatus Willd. : stem much branched, smooth; branches 

 many-flowered ; leaves subclasping, broad-lanceolate, subserrate, 

 smooth ; scales of the involucre lanceolate, loose, as long as the disk. 



HAB. Wet woods. N. Y. to Car. Sept., Oct. U.Stem 24 

 feet high, profusely branched. Upper leaves narrow and nearly 

 entire. Flowers numerous, pale purple ; disk yellow. ; ^ 



31. A. versicolor IVilld.: stem much branched, smooth ; leaves, sub- 

 clasping, broad-lanceolate, smooth, somewhat serrate ; radicle ones 

 serrate in the middle ; scales of the involucre lanceolate, loose, shorter 

 than the disk. 



HAB. Fields and Woods. N. J. to Car. Aug. Oct. L. 

 Stem 2 feet high. Flowers large and very numerous, clustered 

 towards the summits of the branches ; dish yellow; rays white, 

 changing to a deep violet. Pursh. 



32. A. mutabilis Linn. : stem smooth ; branches virgate ; upper 

 leaves somewhat clasping, lanceolate, acuminate, very entire ; lower 

 ones lanceolate, narrow at base, serrate ; scales of the involucre loose, 

 shorter than the disk. .v.trw 



HAB. Fields and woods. Penn. to Virg. Aug. Oct. If. 

 Flowers middle-sized ; dish yellow ; rays deep purple, changing 

 to purple. Pursh. 



33. A. lotvis Linn. : stem smooth, angular ; branches simple, 1 -flow- 

 ered ; leaves somewhat clasping, remote, oblong, very entire, shining ; 

 radical ones subserrate ; scales of the involucre imbricate, subcunei- 

 form, acute, thickened at the apex. 



HAB. Woods and sides of ponds. N. Y. to Virg. Sept. Nov. 

 If. Stem 2 feet high. Flowers large, bluish- purple. 



34. A. concinnus JVilld. : stem simple, paniculate at the summit ; 

 leaves lanceolate-, somewhat clasping ; lower ones smooth, subserrate ; 

 involucre closely imbricate. 



HAB. Woods. N. Y. and Penn. Sept. Nov. UStem 2 

 feet high. Flowers bluish-purple. Leaves, said by Pursh, to re- 

 semble those of Phlox maculata. 



35. A. tardiflorus Linn. : branches divaricate ; leaves sessile, serrate, 

 smooth, spathulate-lanceolate, attenuate at base, margin reflexed ; in- 

 volucre loose ; scales linear-lanceolate, nearly equal, smooth. 



HAB. Low ground. N. S. Sept. Nov. if. rare. Flowers 

 middle-sized ; rays pale blue. 

 16* 



