1040 CONTEIBUTIONS l^EOM THE NATIONAL HERBAEIUM. 



Leaves pilosulous or at least with spreading pubescence on one or both 

 surfaces, the pubescence sometimes chiefly confined to the costa. 

 Leaves rounded or very obtuse at apex. 



Leaves 2 to 3 cm. long, very acute at base 6. E. mayana. 



Leaves 3.5 to 8 cm. long, very obtuse at base 7. E. sinaloae. 



Leaves acute or acuminate ;_8. E. origanoides. 



Leaves glabrous, or sometimes sericeous-strigillose or tomentose, the 

 pubescence, if any, appressed or closely matted. 

 Inflorescence densely sericeous or tomentose; leaves often covered be- 

 neath with pale sericeous pubescence. 

 Leaves narrowly oblong or linear-oblong, rounded at apex. 



9. E. avicenniae. 

 Leaves elliptic-lanceolate to elliptic or obovate, or broader, rarely 

 oblong but then acuminate. 

 Leaves soon glabrous beneath. 



Leaves elliptic or oval, 2 to 3.8 cm. wide 10. E. oaxacana. 



Leaves narrowly oblong-elliptic, 1.3 to 2 cm. wide. 



11. E. inconspicua. 

 Leaves tomentulose or sericeous beneath at maturity. 

 Leaves tomentulose beneath with matted hairs 



12. E. tomeutulosa. 

 Leaves sericeous with very close, straight hairs. 

 Leaves acute or obtuse-acuminate. 



Leaves elliptic or broadly elliptic— 13. E. guatemalensis. 



Leaves oblong 14. E. karwinskyana. 



Leaves rounded or very obtuse at apex. 

 Leaves 1.5 to 3 cm. wide, cuneate-obovate— 15. E. rekoi. 

 Leaves 4 to 6.5 cm wide, rounded or obovate-rounded. 



16. E. hypargyrea. 

 Inflorescence glabrous, puberulent, or minutely hirtellous, never 



sericeous or tomentose; leaves usually quite glabrous, never 

 sericeous or tomentose. 

 Fruit small, 2.5 to 4 mm. long. 

 Leaves very obtuse or rounded at apex, 1 to 2.2 cm. long. 



17. E. liebmannii. 

 Leaves attenuate or acuminate at apex, most of them 3 cm. long 



or larger __18. E. capuli. 



Fruit large, 6 to 10 mm. long or longer. 



Buds 4 to 5 mm. in diameter 19. E. mexicana. 



Buds less than 3 mm. in diameter. 

 Calyx lobes deltoid, acute or acutish. Leaves rounded or very 



obtuse at apex 20. E. deltoidea. 



Calyx lobes suborbicular, rounded at apex. 

 Leaves linear-lanceolate, 4.5 to 6.5 cm. long, 6 to 9 mm. wide. 



21. E. lindeniana. 

 Leaves lanceolate to elliptic. 



Leaves deep green above, much paler beneath. 



22. E. xalapensis. 

 Leaves concolorous or nearly so. 



Leaves small, mostly 3 to 4.5 cm. long, turning black 

 when dry 23. E. axillaris. 



Leaves large, mostly 6 to 10 cm. long, not turning black 

 when dried 24. E. acapulcensis. 



