No. 37. 

 BOUTELOUA ERIOPODA Torrey. 



Perennial, strongly rooted. 



Culms rather weak, straggling, often decumbent and rooting at the lower 

 joints, 1 to 3 feet long, lower part of the culm and sheaths woolly-pubescent, par- 

 ticularly near the roots. 



Leaves of the stem 5 or 6 ; blades narrow, short, 2 to 3 inches long, 1 to 2 lines 

 wide, or from proliferous shoots, sometimes from 4 to G inches long; sheaths much 

 shorter than the internodes. 



Panicle racemose, 3 t to6 inches long, composed of 5 or 6 one-sided nearly 

 sessile spikes; these 1 to 2 inches long, erect-spreading, each containing 15 to 20 

 spikelets. 



Spikelets each with 1 perfect and 1 imperfect flower, 4 to 5 lines long, includ- 

 ing the awns. 



Perfect flower: outer empty glumes lanceolate, acuminate, 1-nerved, very 

 unequal, lower about one-half the length of the upper ; flowering glume pubescent 

 at the base, otherwise smooth, faintly 3-nerved, linear-oblong, 3 lines long, with 2 

 narrow teeth at the apex and a middle one prolonged into an awn 1 line long; 

 palet nearly as long, narrower, 2-nerved, finely 2-toothed at the apex. 



Imperfect flower consisting of 3 slender awns on a pedicel, with a narrow tuft 

 of hair below the united awns; whole 4 to 5 lines long. 



Plate XXXVII: 1, plant of matured size; 2, panicle of a smaller plant; a, 

 empty glumes; b, flowering glume, palet, stamens, pistil, and imperfect flower. 



This is the common black grama grass of southern New Mexico and Arizona, 

 and is the most valuable grass of the mesas. 



