214 I'OACK.E. 



loiif?. awn sluiuler, bent and flcxuosc. 25 



niin, long 15 



m. Empty j,'lnnu's siiboqual, awn twice bont. . (n) 

 n. Empty glumes S-IO nun. long, awn 



•,2(>-4() mm. long, panicle very variable, 



nnmy-llowereil 10 



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



*^0-40 mm. long, panicle I'ew-llowered. . 17 

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



mm. long, culm braacliing, leaves oF 



the culm 7 18 



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



cm. long. S. I'liiini'Hs var. Andcrsoni. 15 

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



mm. long 19 



1. S. var. pennata. Neo-Mexicana Thnrb. 



A rather stout erect smooth grass, 40-GO 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-tlowered, 10-15 cm. long, besides the long awns. Empty glumes 

 eqnal, C-8-nerved, 3 or more mm. wide, and 3-4 cm. long includ- 

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

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

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

 l)art 3-4 cm. long, the whole awn 10-15 cm. long. 



Texas, Revcrchon 1365; Arizona, Jones, Pringle. 



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



2. b. 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. Emi)ty glumes thin, first 5- 



