6o6 



COMPOSITAE 



Leaves firm, smooth; petioles mostly 

 winged. 

 Bracts of the involucre linear and acute, or 

 subulate. 

 Upper cauline, or all the leaves, cordate-clasping. 

 B. Basal and lower leaves with relatively narrow blades, 

 with more or less contracted, petiole-like bases, but 

 not cordate. 

 Stem-leaves clasping by a more or less auriculate-cord- 

 ate base. 

 Stem rough-pubescent or hirsute. 

 Leaves entire. 



Leaves with sessile, strongly cordate- 

 clasping blades. 

 Stem rough-pubescent; involucre 

 campanulate. 

 Inflorescence broad; leaves 



rough; stem relatively low. 

 Inflorescence narrow; leaves 

 soft; stem relatively tall. 

 Stem hirsute; involucre hemispheric. 

 Leaves with slightly clasping bases. 

 Leaves, at least the lower ones, toothed. 

 Stem glabrous or slightly pubescent above. 

 Leaves sharply serrate. 



Leaves tapering to the base. 



Leaves narrowed to the ba^e, the 



lower into winged petioles. 

 Leaves scarcely or gradually na.- 

 rowed to the base. 

 Leaves abruptly contracted into broad, 

 petiole-like bases and often dilated near 

 the stem. 

 Leaves entire or nearly so. 

 Involucre campanulate. 



Cauline leaves oblong to oval-lan- 

 ceolate; inflorescence tending to 

 a raceme-like panicle. 

 Cauline leaves linear or elongated 

 lanceolate; inflorescence tending to 

 a corymb-like panicle. 

 Involucre hemispheric. 



Bracls of the involucre in several 

 series, unequal. 

 Bracts of the involucre linear- 

 subulate; leaves 3-8 mm. wide. 

 Bracts of the involucre merely 

 linear; leaves 6—16 mm. wide. 

 Bracts of the involucre in I or 2 

 series; leaves linear-lanceolate. 

 Stem leaves merely sessile or essentially so, not clasping. 



8. A. Lowrieanus. 



9. A. sagittifolius. 

 10. A. undulalus. 



11. A. patens. 



12. A. phlogifolius. 



13. A. novae-angliii. 



14. A. ante thy stinus. 

 16. A. puniceus. 



15. A. tardiflorus. 



16. A. puniceus. 



17. A. prenanthoid.es. 



18. A. laevis. 



19. A. concinnus. 



20. A . junceus. 



21. A. novi-belgii. 



22. A. longif alius. 



