45 



untouched long they will not eat it unless very hungry, as it becomes tough andl 

 unpalatable and probably difficult to digest. 



19. S. junceus, Kth. Pennsylvania to Wisconsin, and southward 



to Florida. 



20. S. Jonesii, Vasey. California. 



21. S. purpurascens, Hand. Texas. 



22. S. ramulosus, Kth. Colorado to California, New Mexico, andj 



Arizona. 



23. S. serotinus, Gr. Maine, New Jersey, Michigan. 



24. S. tenacissimus, Beauv. On ballast. Introduced. 



25. S. tricholepis, Torr. New Mexico and Arizona. 



26. S. vaginseflorns, (Vilfa, Torr.) Maine to Texas. 



S. vaginseflorns, var. tenera, Vasey. Maine to Texas. 



27. S. Yirginicus, Kth. Virginia to Texas, near the coast. 



28. S. "Wolfii, Vasey. Colorada. A minute species. 



29. S. Wrightii, Mun.ro. New Mexico to Arizona. 



Epioamfes, Presl. 



Spikelets much as in /Sporobolus, but contracted in a long, narrow,, 

 and dense panicle. Outer glumes somewhat unequal, membrana- 

 ceous, convex on the back, scarcely keeled, obtuse, three-nerved ; 

 flowering glume mostly equalling the outer ones, sometimes three to 

 five nerved, entire or sometimes asvned from the apex ; palet hyaline,, 

 about equalling the flowering glume, two nerved or two-keeled. 



1. E. distichophylla, Vasey. (Muhlenbergia, Munro.) Texas to- 



Arizona. 



2. E. macroura, Benth. (Cinna, Kth.) Texas to Arizona. 



3. E. rigens, Benth. (Cinna macroura, Thurb.) Arizona to Cali- 



fornia. 



Agkostis, Linn. 



Spikelets one-flowered in a contracted or open panicle; outer 

 glumes nearly equal or the lower rather longer, and longer than the 

 flowering glnme, one-nerved, acute, unawned ; flowering glume 

 shorter and wider, hyaline, three to five nerved, awnless, or some- 

 times awned on the back ; palet shorter than the flowering glume,, 

 frequently reduced to a small scale or entirely wauting. Stamens 

 usually 3, grain free. 



