312 COMPOSITAE 



3. Vernonia mazima Small. Tai,i, Iron-weED. (Man. p. 919; I. 

 F. f. 3605. ) In moist soil, Pa. to Ala., Mo., Ky. and La. — Pennsylvania : 

 Ai,i<egheny; Erie. 



2. elbphantopus l. 



1. Elophantopus Carolinianua Willd. Carowna Ei<EPHANT'S FOOT. 

 (Man. p. 920 ; I. F.y. sbog.) In dry woods, N. J. and Pa. to Fla., Kans. 

 and Tex. — Pennsylvania : Det-aware ; Lancaster, Peach Bottom. 



3. EUPATORIUM L. 



Receptacle flat : disk white, pink or purple. 

 Leaves whorled in 3's or 6's ; blades relatively broad. 

 Leaf-blades rugose, manifestly pubescent : inflorescence depressed. 



I. E. maculatum. 

 Leaf-blades not rugose, nearly glabrous : inflorescence pyramidal. 

 Leaf-blades sharply serrate. ■^. E. purpureum. 



Leaf-blades crenate, the teeth somewhat apiculate. 



3. E. trifoliatum. 

 Leaves opposite or whorled in individual cases in some narrow-leaved forms. 

 Leaves connate-perfoliate. 4. E. per/oliatum. 



Leaves not connate-perfoliate. 

 Leaf -blades sessile or essentially so. 

 Base of the leaf-blade not broader than the rest of the blade, often 

 narrowed. 

 Bracts of the involucre obtuse. 

 Leaf-blades of a linear type, entire or shallowly and irregularly 



toothed. 5. E. hyssopifolium. 



Leaf-blades of a lanceolate, oblong, ovate or oval type, markedly 

 toothed. 

 Blades of the upper leaves toothed from near the base to the apex. 



6. B. Torreyanum. 

 Blades of the upper leaves toothed above the middle. 



7.' E. altissimum. 

 Bracts of the involucre acute or acuminate. 8. E. album. 

 Base of the leaf-blade broadly rounded, cordate, truncate, or broadly 

 cuneate. 

 Leaf-blades crenate, crenate-serrate or crenate-dentate. 

 Branches of the inflorescence alternate ; leaf-blades coarsely few- 

 toothed. 9. E. verbenaefolium. 

 Branches of the inflorescence opposite : leaf-blades more finely 

 and evenly toothed. 

 Leaf-blades about as broad as long, truncate or subcordate at the 

 base. 10. E. rotundifolium. 

 Leaf-blades manifestly longer than broad, rounded or broadly 

 cuneate at the base. w. E. pubescens. 

 Leaf-blades sharply serrate. 12. E. sessilifolium. 

 Leaf-blades manifestly petioled. 

 Leaf -blades acuminate. 13. E. ageratoides. 

 Leaf-blades obtuse or abruptly acute. 14. E. aromaticum. 

 Receptacle conic or hemispheric : disk blue to violet, or white in individual 

 cases. 15. E. coelestinum. 

 1. Eupatorium maculatum L. Spotted Joe-pye Weed. (Man. p. 

 921 ; I. -p. f. 3614.) In moist soil, N. Y. to Minn., B. C, N. C, Kans. 



