WILD FLOWERS OF NEW YORK 



303 



Stems rough; leaves oblong to lanceolate; involucre turbinate 



Leaves thick, firm, very rough, oblong to oval 



23 A. patens 



Leaves thin, roughish, oblong-lanceolale 



24 A. p h 1 o gi f o 1 i u s 

 Stem glabrous, or only sparingly pubescent above 

 Leaves sharply serrate 



Leaves tapering to the base 



Leaves narrowed to the base, the lower into winged petioles 



25 A. tardiflorus 



Lea\-es scarcely or gradually narrowed at the base 



20 A. pu ni c eu s 

 Leaves abruptly contracted into margined petioles, often enlarged near 



the base 26A. prenanthoides 



Leaves usually strongly cordate-clasping; bracts green-tipped 



27 A. 1 a e V i s 

 Leaves entire or nearly so 



Livolucre campanulate, its bracts appressed, green-tipped 



Stem leaves oblong, lanceolate or oval-lanceolate. .27 A. 1 a e \- i s 



Stem leaves elongated-lanceolate 28 A. concinnus 



Involucre hemispheric 



Bracts in one or two series; leaves linear to lanceolate 



2 g A . 1 o n g i f o 1 i u s 

 Bracts in se\-eral series, unequal 



Bracts linear-subulate; leaves narrowly linear 



30 A. j u n c e u s 



Bracts lanceolate, leaves lanceolate, 2 to 6 inches long 



31 A. no vi -b e 1 g i i 

 C Leaves sessile or jDCtioled, scarcely or not at all clasping 



Leaves silky or silvery-canescent, entire; heads in a narrow raceme; bracts linear 



32 A. c o n c o 1 o r 

 Leaves neither silvery, silky nor canescent ; leaves entire or toothed 

 Bracts of the involucre with herbaceous tips 



Tips of the involucral bracts spreading (little spreading in A. r a d u 1 a , 

 erect or spreading in A. h e r v e y i) ; heads large, showy; rays 

 violet to purple 



