Dec, 1917] The Asterece of Ohio 45 



inflorescence. Involucre campanulate, its bracts oblong, ciliate, 

 pubescent, the outer with green reflexed tips. Pappus brown 

 or white. In dry woods. July-September. Cuyahoga, Sum- 

 mit, Wayne, Holmes, Fairfield, Hocking, Jackson, Gallia, 

 Lawrence. 



Aster L. Aster. 

 Fall blooming herbs with branching stems, mostly perennial. 

 Leaves alternate. Heads of various sizes forming a corymbose 

 or paniculate inflorescence; involucre hemispherical, cam- 

 panulate, or turbinate, of various kinds of bracts, imbricated 

 in several rows, the outer usually shorter; ray flowers white, 

 pink, purple, blue, violet or rarely yellow; disk flowers bispor- 

 angiate, usually yellow, becoming brown or purple. Pappus 

 of numerous, slender bristles, scabrous or denticulate and mostly 

 in one series. Achenes mostly flattened and nerved. 



Key to the Species. 



1. Lower stem and basal leaves cordate and definitely petioled. 2. 



1. None of the leaves cordate and definitely petioled. 12. 



2. Stem leaves cordate-clasping. A . undulatiis. 



2. Stem leaves petioled or sessile, not clasping. 3. 



3. Ra^'s white. 4. 



3. Rays blue or violet. 5. 



4. Leaves thick, rough; inflorescence glandular. A. macrophyllus. 



4. Leaves thin, smooth, inflorescence not glandular. A . divaricattis. 



5. Plant not glandular. 6. 



5. Branches of the inflorescence glandular. A. macrophyllus. 



6. Leaves entire or nearly so, thick and firm. 7. 



6. Leaves mostly sharply serrate, thin. 8. 



7. Leaves glabrous above or nearly so. A. shortii. 



7. Leaves rough-pubescent on both sides; the upper bract-like. A. azureus. 



8. Involucre H-J^ in. high, bracts appressed, with conspicuously colored tips. 9. 



8. Involucre Y^-V-z in. high, bracts loose, without conspicuously colored tips. 10. 



9. Cordate leaves mostly on smooth petioles, rough. A. cordifolius. 

 9. Cordate leaves mostly on winged petioles, smooth. A. lowrieaims. 



10. Heads loosely paniculate or subcorymbose. A. lindleyanus. 



10. Heads densely racemose-paniculate. 11. 



11. Stem glabrous or nearly so. A. sagittifolius. 



11. Stem densely short pubescent. A. dnimmondii. 



12. Stem leaves or some of them with more or less clasping cordate bases, none 



of them both cordate and petioled. 13. 



12. Stem leaves without cordate and clasping bases, sessile, or petioled. 22. 



13. Stem rough or hirsute-pubescent. 14. 



13. Stem glabrous or only sparingly pubescent above. 18. 



14. Leaves or some of them serrate. A. puniceus. 



14. Leaves entire. 15. 



15. Heads J^-1 in. broad; leaves large, slightly clasping. A. oblongifolius. 



15. Heads 1-2 in. broad; leaves strongly cordate and clasping. 16. 



16. Branchlets of the inflorescence glandular viscid; involucre hemispherical. 



A . nova-anglics. 



16. Branchlets of the inflorescence not glandular viscid; involucre turbinate. 17. 



17. Leaves thick and firm, very rough, oblong to oval. A. patens. 

 17. Leaves thin, roughish, oblong-lanceolate. 18. 



