46 The Ohio Journal of Science [Vol. XVIII, No. 2, 



18. Stem leaves sharply serrate. 19. 



18. Stem leaves entire or nearly so. 21. 



19. Leaves tapering to the base. A. puniceus. 



19. Leaves not tapering to the base. 20. 



20. Leaves abruptly contracted into margined petioles, often enlarged at the base. 



A. prenanthoides. 



20. Leaves strongly cordate clasping, bracts green tipped. A.Icevis. 



21. Bracts of the involucre with rhomboid green tips. A. lavis. 



21. Bracts of the involucre narrow, not folicaeous, leaves narrowly linear. 



A . junceus. 



22. Involucral bracts without green tips, leaves narrow, entire. A. paniculattis. 



22. Involucral bracts with green tips. 23. 



23. Heads in more or less 1-sided racemes. 24. 



23. Heads not in 1-sided racemes, mostly paniculate. 26. 



24. Stem leaves oblong to lanceolate, serrate or mostly so. 25. 



24. Stem leaves linear-lanceolate to linear, nearly entire; stem glabrate. 



A. vimineus. 



25. Stem pubescent or glabrate. A. lateriflorus. 



25. Stem villous; leaves narrowly lanceolate, thin. A. hirsuticaulis. 



26. Involucral bracts appressed, acute. 27. 



26. Involucral bracts spatulate, mostly ciliate, somewhat spreading, at least 



the outer obtuse; heads numerous. 



A. miiltifloriis. 



27. Heads solitary at the end of very small leafy branches. A. dumosus. 



27. Heads paniculate. 28. 



28. Stem leaves lanceolate, serrate or entire. 29. 



28. Stem leaves linear-lanceolate to lanceolate, mostly entire. 31. 



29. Heads ^A-% in. broad. 30. 



29. Heads 3^-M in. broad, stem leaves narrowly lanceolate. A. tradescanti. 



30. Leaves firm, rough or roughish; rays often purplish; involucral bracts acute. 



A. salicif alius. 



30. Leaves thin, smooth; rays chiefly white; involucral bracts acuminate. 



A. paniculatus. 



31. Heads scattered, l^-^i in. broad; the upper leaves linear. A. faxoni. 



31. Heads numerous, 34~K in. broad; the upper leaves subulate. 32. 



32. Stem smooth; leaves linear-lanceolate. A. ericoides. 

 32. Stem densely villous; leaves oblong-lanceolate to lanceolate. 



A . ericoides var. platyphyllus. 



1. Aster divaricatus, L. White Wood Aster. Tufted 

 plants with slender, assurgent, somewhat zig-zag stems, 1^-2^ 

 ft. high, becoming glabrate with maturity. Leaves thin, 

 ovate-lanceolate, serrate with sharp spreading teeth, acuminate 

 or acute at the apex and cordate at the base, on slender petioles; 

 inflorescence leaves smaller, ovate and acute. Heads f-1 in. 

 broad, in a flatfish forked corymb of long slender divergent 

 branches; rays 6-9, linear, white; disk turning brown; bracts 

 of the involucre mostly obtuse, ciliate, with inconspicuous green 

 tips, the outer short and oblong, the inner linear. In open 

 woodlands and thickets, in rather dry soil. September-October. 

 Meigs, Franklin, Fairfield, Lorain, Erie. 



2. Aster macrophyllus L. Largeleaf Aster. Rough plants 

 from long, thick rootstocks; stems reddish, smooth, often 

 grandular-viscid in the inflorescence. 2-3 ft. high. Basal 



