178 



POACEAE 



4. Bouteloua barbata Lag. 

 Annual Grama. Fig. 403. 



Bouteloua barbata Lag. Var. Cienc. 2*: 141. 1805. 

 Chondrosium polystachya Benth. Bot. Voy. Sulph. 56. 1844. 

 Bouteloua polystachva Torr. U. S. Rep. Expl. Miss. Pacif. 

 5: 366. pi. 10. 1857. 



Annual ; culms spreading or prostrate, 15-30 cm. 

 tall ; spikes usually 4-6. about 1-2 cm. long ; per- 

 sistent on the main axis ; spikelets numerous, imbri- 

 cate ; glumes persistent, unequal, scabrous on keel 

 and somewhat so on back, awn-pointed from a 

 toothed apex, the second twice as long as the first, 

 3 mm. long ; lemma pilose below, 3-awned, the 

 awns about 2 mm. long, the lemma lobed between 

 the awns ; rudiment pilose at base, 2-lobed, 3-awned, 

 enclosing an orbiculaar scale. 



Deserts, Utah to southern California (The Needles, Jones) 

 and south into Mexico. Type locality: Mexico. 



5. Bouteloua rothrockii Vasey. 

 Roth rock's Grama. Fig. 404. 



Bouteloua rothrockii Vasey, Contr. U. S. Nat. Herb. 1: 268. 

 1893. 



Perennial ; culms erect or spreading, 30-60 cm. tall ; 

 spikes several, usually 4-6, 1-2.5 cm. long; persistent 

 on the main axis, spikelets numerous, imbricate ; 

 glumes persistent, unequal, scabrous on keel and back, 

 cuspidate and 2-toothed at apex, the second 2.5 mm. 

 long, about twice as long as the first ; lemma pilose 

 below, 4-lobed, 3-awned, the awns equal, 2.5 mm. long ; 

 rudiment pilose at base, consisting of 2 short truncate 

 lobes, 3 equal awns about 1 mm. long and an included 

 orbicular scale. 



Mesas and foothills, Utah to southern California (Jamacha, 

 Canby) and Mexico. Type locality: Arizona. 



6. Bouteloua radicosa Griffiths. 

 Purple Grama. Fig. 405. 



Dincbra bromoides H. B. K. Nov. Gen. & Sp. 1: 172. pi. 51. 



1816, not Bouteloua bromoides Lag. 

 Atheropogon radicosns Fourn. Mex. PI. 2: 140. 1886. 

 Bouteloua radicosa Griffiths, Contr. U. S. Nat. Herb. 14: 411. 



pl. SI. 1912. 



Perennial in dense tufts; culms 15-60 cm. tall, erect; 

 blades mostly basal. Hat, sparsely ciliate toward the 

 base ; spikes several to many, 2-2.5 cm. long, irregularly 

 1-sided, falling entire ; glumes somewhat unequal, rather 

 broad, the second about 6 mm. long; lemmas smooth, 

 bearing 3 short awns ; rudiment lanceolate, with 3 long 

 awns. 



Upper foothills and mountains, southern California (Orcutt) 

 and New Mexico to Mexico. Tyiie locality: Mexico. 



