238 COMPOSITE FAMILY. 



x x Leaves with few or many prominent teeth. 

 + Leaf base distinctly clasping. 



A. prenantholdes, Mulil. l-3, hairy above in lines ; leaves ovate- 

 lanceolate, rough above and smooth beneath, narrowed into a long entire 

 portion which is suddenly dilated into an auricled base ; heads on short 

 divergent peduncles, pale violet or whitish. Along streams, N. 



A. punlceus, Linn. Tall and stout, 3-7, rough-hairy all over (or in 

 some forms smoothish below) ; leaves oblong-lanceolate and but little 

 narrowed at the base ; heads subsessile, in a panicle or thyrse ; flowers 

 large, purple to white. Variable. N. ; S. to Ga. 



+ + Leaf base wing-petiole-like , not auriculate. 



A. patulus, Lam. Glabrous or nearly so, l-4 ; leaves ovate or 

 oblong- lanceolate, serrate in middle, narrowed at both ends, the lower 

 ones into a winged petiole ; heads loosely panicled, violet or white ; scales 

 unequal. N. Eng. 



A. Ellidttii, Torr. & Gray. Stem (2-3) minutely pubescent ; leaves 

 thickish, oblong-lanceolate, appressed-toothed, tapering into a narrow, 

 petiole-like contraction ; heads numerous, corymbose-paniculate, purple ; 

 scales nearly equal. S. C. to Fla. 



o o Leaves (mostly narrower) not cordate-clasping, nor with wing-sessile 



bases. 



x Involucre and branchlets viscid or glandular. 

 + Leaves rigid and obtuse. 



A. grandifl6ras, Nutt. Slender, hispid, l-3; leaves very small, 

 linear ; rays violet, long. Handsome. Va. , S. 



+ + Leaves soft and acute. 



A. oblongif61ius, Nutt. Minutely glandular-puberulent, l-2 ; leaves 

 narrow-oblong or lanceolate, mucronate, somewhat clasping; flowers 

 rather small, purple. Banks, N. 



A. spectabilis, Ait. Roughish, stout, l-2, leaves oblong-lanceolate 

 or spatulate-oblong, mostly entire ; heads few, large and showy (purple), 

 the scales with the upper half herbaceous and spreading. Near the coast, 

 Mass, to Del. 



x x Not viscid or glandular (except, perhaps, in A. surculosus). 



+ Radical leaves tapering into margined petioles. 



Leaves entire or obscurely serrate. 



A. 8urcul6sus, Michx. Low (1 or less), with filiform rootstocks; 

 leaves linear or lanceolate, rigid ; heads medium-sized, few or solitary, 

 light purple. Near coast, N. J., S. 



A. gracilis, Nutt. Leaves oblong-lanceolate and small ; scales coria- 

 ceous and whitish, with short-ovate green tips ; heads few. Pine barrens, 

 N. J., S. and W. Leaves sharply serrate . 



A. radula, Ait. Smooth or lightly hairy, leafy, l-3 ; leaves oblong- 

 lanceolate, pointed, rugose, rough both sides, very closely sessile ; scales 

 with short, spreading green tips ; flowers light-violet. N. Eng. to Del. 



+ + Radical leaves not with margined petioles. 



Involucral scales squarrose or with prominently spreading green tips ; 

 leaves small, linear and entire ; heads small and racemose. 



A. amethystinus, Nutt. Tall and erect, 2-5, somewhat hirsute, 

 branchy ; leaves lax ; scales with only the tips spreading ; rays light blue, 

 Mass, to la. 



