MANUAL OF THE GRASSES OF THE UNITED STATES 



443 



the twisted column 6 to 14 mm long; awns about equal, divergent, 2 

 to 3 cm long. % — Open dry ground, southern Arizona to Baja 

 California. 



Section 2. Uniseta Hitchc. 



Lateral awns minute (less than 1 mm long) or wanting, (see also .4. 



dichotoma and A. ramosissima of Section Chaetaria); lemma 



not articulate with the column of the awn. 

 5. Aristida ternipes Cav. Spider grass. (Fig. 939.) Perennial; 

 culms erect, 50 to 100 cm tall; blades flat, involute toward the end 



Figure 937.— Aristida californica, X L 

 (Kearney 3524, Ariz.) 



Figure 938.— Aristida glabrata. X 1. 

 (Griffiths 7312, Ariz.) 



and tapering into a fine point as much as 40 cm long, 2 to 3 mm wide ; 

 panicle open, one third to half the entire height of the culm, the 

 branches few, distant, spreading, scabrous, mostly naked at the base ; 

 spikelets appressed at the ends of the branches; glumes about equal. 

 8 to 10 mm long; lemma glabrous, often strongly scabrous on the keel, 

 gradually narrowed into a laterally compressed scabrous falcate beak, 



