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-lanceolate 



24 A. phlogifolius 



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 



Leaves scarcely or gradually narrowed at the base 



20 A. puniceus 

 Leaves abruptly contracted into margined petioles, often enlarged near 



the base 26 A. prenanthoides 



Leaves usually strongly cordate-clasping; bracts green- tipped 



27 A. laevis 

 Leaves entire or nearly so 



Involucre campanulate, its bracts appressed, green -tipped 



Stem leaves oblong, lanceolate or oval-lanceolate. .27 A. laevis 



Stem leaves elongated-lanceolate 28 A. concinnus 



Involucre hemispheric 



Bracts in one or two series; leaves linear to lanceolate 



29 A. longifolius 

 Bracts in several series, unequal 



Bracts linear-subulate; leaves narrowly linear 



30 A. j u n c eu s 



Bracts lanceolate, leaves lanceolate, 2 to 6 inches long 



31 A. novi-belgii 

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



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



32 A. concolor 



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. herveyi); heads large, showy; rays 

 violet to purple 



