410 



MISC. PUBLICATION 200, U. S. DEPT. OF AGRICULTURE 



Figuke 582. — Muhlenbergia rigida. Panicle and ligule, X 1 ; glumes and floret, X 10. (Metcalfe 1447, N. Mex.) 



as long as the glumes, narrowed and 

 scabrous above, villous below, with a 

 delicate flexuous awn, about 1.5 cm. 

 long, or sometimes awnless. 01 — 

 Rocky woods and ravines, Texas to 

 Arizona and Mexico. A good soil 

 binder on steep slopes. 



68. Muhlenbergia rigens (Benth.) 

 Hitchc. Deergrass. (Fig. 587.) 

 Culms rather slender, stiffly erect, in 

 small bunches, with a hard tough 

 base, 1 to 1.5 m. tall; sheaths smooth 



Figure 583. — Muhlenbergia longiligula. Panicle and 

 ligule, X 1; glumes and floret, X 10. (Jones, Ariz.) 



slender, 1.5 to 2 mm. long. 91 — 



Canyons and ravines, southern Texas. 



67. Muhlenbergia emersleyi Va- 



sey. Bullgrass. (Fig. 586.) Culms 

 in large clumps, erect, 50 to 100 cm. 

 tall; sheaths glabrous, slightly sca- 

 brous, compressed-keeled, especially 

 those of the innovations; ligule softly 

 membranaceous, 1 to 2 cm. long; 

 blades flat or folded, scabrous, 1 to 4 

 mm. wide, the lower as much as 50 

 cm. long; panicle narrow but rather 

 loose, erect or nodding, mostly 20 to 

 40 cm. long, the branches ascending, 

 more or less fascicled or whorled, 

 naked below; spikelets 2.5 to 4 mm. 

 long, often purplish; glumes thin, 

 equal, acutish, scabrous; lemma about 



Figure 584. — Muhlenbergia lindheimeri. Panicle, X 1; 

 glumes and floret, X 10. (Type.) 



