No. 10. 



ORYZOPSIS MEMBRANACEA (Pursh.). (Stipa membranacea Pursh.) 



Eriocoma cuspidata Nutt.) 



Plant perennial, closely tufted, thickened at base. . 



Culms slender, nearly erect, not branching, geniculate, solid, terete, smooth, 

 12 to 18 inches tall. 



Leaves; radical, numerous, the scarious sheaths clustered thick about the base 

 of the culms; blades involute, smooth, 6 to 10 inches long; of the culms 3; lower 

 sheaths shorter than internodes, smooth and close, upper sheath longer and loose; 

 blades like those of radical leaves; ligule membranaceous, ovate, acute, or lace- 

 rate, 1 line long, prominently decurrent. 



Inflorescence a very loose, erect or flexuous panicle 4 to 6 inches long, included 

 at the base, usually with 2 or 3 nearly equal axes; branches mostly in pairs, dis- 

 tant, horizontal, divided in pairs beyond the middle, bearing solitary spikelets on 

 long flexuous pedicels. 



Spikelets 1-flowered, 3 lines long; first and second glumes equal, inflated and 

 widened below, narrowed above to a long sharp point, scarious except the 5 rather 

 obscure nerves, minutely pubescent throughout, 3 lines long; floral glume ovoid 

 or oblong, hard, dark-brown, profusely clothed with long white hairs, 1^ lines 

 long, obscurely nerved, terminating in an awn 2 lines long, which falls at maturity; 

 palet conical, smooth, hard, brown, obscurely nerved, li lines long. 



Grain oval, light-yellow, f line long. . 



Plate X; a, spikelet; b, empty glumes; c, floral glume, with hairs and awn: 

 d, same after hairs and awn have fallen; e, palet. In the floral glume, e, the awn 

 should be represented more to one side. 



Texas to California, northward to British Columbia, usually in sandy or grav- 

 elly soil. A valuable grass. The large seeds are nutritious, and cattle fatten 

 where the grass is abundant. 



