MANUAL OF THE GRASSES OF THE UNITED STATES 



383 



cm tall; sheaths with erect firm auricles, 4 to 10 mm long, rarely 

 longer; blades involute, scabrous; panicle narrow, sometimes almost 

 spikelike, grayish, 10 to 30 cm long, rarely longer; spikelets about 

 4 mm long; glumes about half as long as the spikelet, minutely sca- 

 berulous, obtuse; lemma minutely scaberulous, with an awn as much 

 as 4 mm long, rarely acuminate only. 01 (M. acuminata Vasey; 



Figure 791.— Distribution of 

 Muhlenbergia pauciflora. 



FIGURE 790. — Muhlenbergia pauciflora. Plant, X 1; glumes 

 and floret, X 10. (Wright 732, Tex.) 



Sporobolus ligulatus Vasey and Dewey.) — Canyons and rocky hills, 

 western Texas to Arizona and northern Mexico. 



46. Muhlenbergia rigida (H.B.K.) Kunth. Purple muhly. 

 (Fig. 800.) Perennial, densely tufted; culms erect, 60 to 100 cm 

 tall; leaves crowded at base, old sheaths persistent, the sheaths with 

 auricles 2 to 5 mm, rarely longer; blades flat or soon involute, flexuous, 

 those of the innovations involute ; panicle dark purple, narrow, finally 

 loose and open, 15 to 30 cm long, the capillary branches ascending, 



55974°— 35 25 



