No. 13. 

 MUHLENBERGIA NEO-MEXICANA Vasey. 



Plant slender, tufted, perennial, from thick, knotted, or sometimes creeping 

 rootstocks. 



Culm branching freely below, erect, slender, terete, nearly smooth, 12 to 18 

 inches tall. 



Leaves; of culms 4 to 6; sheaths longer than internodes, close, slightly rough- 

 ened; blades erect, appressed, closely involute and setaceous, 2 to 3 inches long; 

 ligule an irregular, ovate, lacerate membrane i line long. 



Inflorescence a narrow, erect or slightly nodding panicle, 3 to 4 inches long, 

 often purple; branches alternate, erect, hispid, i to 1 inch long, bearing rather 

 close clusters of spikelets on hispid pedicels to li lines long. 



. Spikelets narrow, 1-flowered, 2 lines long; empty glumes equal, lance-ovate, 

 acute, carinate, hyaline, 1-nerved, 1 line long, terminating in a slender awn i to ^ 

 line long; floral glume narrowly conical, lanceolate, acute when unrolled, thin, 

 smooth, minutely pubescent at base, 3-nerved, terminating in an awn $ inch long; 

 palet obscurely 2-nerved, 2 lines long, often projecting out of the floral glume; 

 stamens 3. 



Grain, none present in the 24 specimens examined. 



PLATE XIII ; a, panicle at maturity; b, cluster of spikelets; c, spikelet enlarged. 

 Eocky ledges. New Mexico and Arizona. 



