2] 4 POACE^. 



long, awn slender, bent and flexnose, 25 



mm. long 15 



m. Empty glumes snbequal, awn twice bent. . (n) 

 n. Empty glumes 8-10 mm, long, awn 



20-40 mm. long, panicle very variable, 



many-flowered 16 



n. Empty glumes 5-10-13 mm. long, awn 



20-40 mm. long, panicle few-flowered. . 17 

 n. Empty glumes 8 mm. long, awn 15-50 



mm. long, culm branching, leaves of 



the culm 7 18 



n. Empty glumes 6-7 mm. long, awn 2-2.5 



cm. long. S. eminens var. Andersoni. 15 

 n. Empty glumes 5 mm. long, awn 16-18 



mm. long 19 



1. S. var. pennata, Neo-Mexicana Thurb. 



A rather stout erect smooth grass, 40-60 cm. high. Sheaths 

 mostly longer than the internodes; leaves of sterile shoots numer- 

 ous, strict, blades narrow, 30-40 cm. high, those of the culm 4 in 

 number. Panicle partly included by the upper sheaths, simple, 

 few-flowered, 10-15 cm. long, besides the long awns. Empty glumes 

 equal, 6-8-nerved, 3 or more mm. wide, and 3-4 cm. long includ- 

 ing the long-drawn-out point; floret pubescent, 15 mm, long, includ- 

 ing the long callus ; awn pubescent or flexuose, plumose through- 

 out (the hairs near the middle 2 mm. long), twice bent, the lower 

 part 3-4 cm. long, the whole awn 10-15 cm. long. 



Texas, Reverclwn 1365 ; Arizona, Jones, Prinrjle. 



Found in West Texas, New Mexico, Arizona, Colorado. 



2. S. occidentalis Thurb. S. Wats. Bot. King's Expd. 380 

 (1871). 



Culms erect, slender, scabrid, pubescent at the nodes, 30-60 cm. 

 high. Sheaths shorter than the internodes; ligule 4-5 mm. long; 

 blades rigid, slender, involute, scabrid, the lower 6-15 or more cm. 

 long, those of the culm usually two in number, 1-10 cm. long. 

 Panicle exserted or the base included, simple, narrow, 5-15 cm. 

 long, the lower rays in twos or threes. Empty glumes thin, first 5- 



