598 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



Leaves 6 to 30 cm. long or larger ; bracts suborbicular. 



Leaves mostly 6 to 15 cm. long, the blade decurreut to tlie base of 



the petiole 3. E. calyculata. 



Leaves about 30 cm. long, on naked petioles 4. E. elata. 



Glands of the involucre with petal-like appendages. 



Plants normally leafless 7. E. antisyphilitica. 



Plants leafy, at least in the inflorescence. 



Appendages bright red ; leaves glabrous 8. E. fulgens. 



Appendages white or yellowish or, if reddish, the leaves pubescent. 



Involucres glabrous 9. E. califomica. 



Involucres pubescent. 



Stems naked, the inflorescence leafy 10. E. consoquitlae. 



Stems leafy. 

 Stems very thick, gnarled and crooked, woody throughout. 



11. E. misera. 

 Stems long and slender, suffrutescent. 



Leaves glabrous or nearly so 12. E. tresmariae. 



Leaves densely pilose beneath, at least when young. 



13. E. oaxacana. 

 AA. Leaves all opposite or verticillate. 



Leaves opposite, more or less oblique at base, usually distichous, sometimes 

 dentate ; stipules deltoid to linear. 



Leaves finely toothed 14. E. tomentulosa. 



Leaves entire. 



', Leaves acute 15. E. fruticulosa. 



Leaves rounded or obtuse at apex. 

 Capsule glabrous ; leaves mostly 1 cm. long or shorter. 



16. E. magdalenae. 



Capsule puberulent; leaves mostly 1 to 2 cm. long 17. E. anthonyi. 



Leaves mostly verticillate, not oblique at base, entire ; stipules glandlike. 



Leaves linear 18. E. peganoides. 



Leaves lanceolate to orbicular. 



Involucres glabrous, the appendages nearly obsolete. 



19. E. schlechtendalii. 

 Involucres sparsely or densely pubescent, the appendages well developed. 

 Appendages of the glands linear to oblong, much longer than broad. 



Appendages cleft into linear lobes 20. E. chiapensis. 



Appendages not cleft into linear lobes. 

 Bracts of the inflorescence inconspicuous, small, green. 



21. E. tricolor. 



Bracts conspicuous, large, white 22. E. leucocephala. 



Appendages broadly ovate to reniform, as broad as long or i)roader. 

 Bractlets of the inflorescence white or pink, conspicuous. 



23. E. lucii-smithii. 

 Bracelets green, iuc-juspicuous. 



Leaves orbicular or nearly so, mostly 4 to 13 cm. wide. 



24. E. cotinifolia. 

 Leaves oblong or oblanceolate to ovate, 3 cm. wide or less. 



Appendages longer than the tube of the involucre 25. E. xanti. 



Appendages shorter than the tube of the involucre. 



Leaves obovate or oblanceolate, broadest above the middle, 



;; usually pubescent beneath 26. E. plicata. 



Leaves mostly ovate or elliptic, broadest at or below the mid- 

 dle, glabrous or nearly so 27. E. colletioides. 



