No. 42. 

 BOUTELOUA PROSTRATA Lagasca. 



Annual. Roots fibrous. 



Culms growing in small depressed tufts, spreading or decumbent, geniculate, 

 leafy to the top. 



Leaves with short narrow blades ^ to H inches long; sheath somewhat loose, 

 shorter than the internodes, striate; ligule inconspicuous. 



Inflorescence a single terminal spike, generally recurved, % to 1 inch long, 

 smooth. 



Spikelets 20 to 30, in rows on one side of the smooth rachis, nearly 3 lines long, 

 containing 1 perfect and 2 imperfect flowers. 



Empty glumes unequal; lower about one-half the length of the upper, narrow; 

 upper about 2 lines long, ovate-lanceolate, acute ; flowering glume smooth or 

 slightly pubescent on the back, about 3 lines long, lower half broadly oblong, tipper 

 3-lobed, 3-awned, middle lobe broadest and longest, awns stiff. 



Palet nearly 2 lines long, denticulate at the apex. Imperfect flower reduced 

 to 3 stiff awns with 1 or 2 scales at the base, on a short pedicel having a tuft of 

 white hairs at the top. 



Plate XLII: a, spikelet; b, empty glumes; c, flowering glume from the back;' 

 d, palet; e, imperfect flower. 



This annual grass is widely distributed from Mexico to Colorado, prevailing 

 in bottom lands, where it frequently mats the ground, but does not seem to be 

 relished by cattle. 



