108 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



I. EUAGAVE. Flowers in a panicle. 



A. Leaves without a horny border, the spine at most deciirrent for little more 

 than its length. 

 B. Leaves hard-fibrous, swordlike or dagger-like or else under 10 em. wide. 

 C. Marginal teeth numerous and strong. 



Teeth close together (5 to 10 mm. apart) and very slender. 



Leaves green 1. A. panamana. 



Leaves gray-green, purple-green, or very glaucous. 



Leaves gray-green or purple-green 2. A. rubesceiis. 



Leaves very glaucous ^ 3. A. stringens. 



Teeth more separated or heavier. 



D. Spine elongate, biconvex 4. A. angustifolia. 



DD. Spine elongate, half-round or very openly grooved. 



Leaves rough-granular 5. A. bergeri. 



Leaves smooth. 



Teeth slender 6. A. lespinassei. 



Teeth heavy. 



Teeth scai-cely raised 7. A. endlichiana. 



Teeth on fleshy bases 36. A. sicaefolia. 



DDD. Spine needle-shaped, round-grooved. 



Teeth heavy or raised 8. A. aboriginum. 



Teeth slender 9. A. deweyana. 



DDDD. Spine short and thick or subulately tapered, biconvex or shallow- 

 grooved at base. 



E. Spine subulately slender. 



Spine chestnut. Teeth small 10. A. zapupe. 



Spine red-brown or graying. 



Spine red-brown ; teeth small 20. A. donnell-smitMi. 



Spine graying; teeth larger 11. A. subtilis. 



EE. Spine similar but larger and stouter. 

 Teeth separated (30 mm. apart or more). 



Teeth heavy-based 12. A. longisepala. 



Teeth very slender 13. A. pedrosana. 



Teeth closer (scarcely 20 mm. apart), slender. 



Leaves green 14. A. gutierreziana. 



Leaves gray or white. 



Leaves gray 15. A. elongata. 



Leaves white 16. A. collina. 



EEE. Spine not subulate, or else short. 



Spine graying. Teeth large 17. A. palmaris. 



Spine red-brown. 



Teeth large 18. A. rhodacantha. 



Teeth rather small. 



Teeth close (10 mm. apart): 19. A. pes-mulae. 



Teeth distant 20. A. donnell-smithii. 



DDDDD. Spine conical, often round-grooved at base. 



F. Leaves green. 



I Plants arborescent. 



Teeth heavy 21. A. karwinskii. 



Teeth very slender-cusped 22. A. decipiens. 



Plants short-stemmed or acaulescent. 



Teeth few or slender 23. A. sisalana. 



Teeth numeroiis, tapered 24. A. candelabrum. 



