W00T02Sr AND STANDLEY FLORA OF NEW MEXICO. 69 



Lemmas scabrous or glabrous. 



Panicles dense, obtuse, 5 to 10 



mm. mde 13. M. wrightii. 



Panicles rather lax, tapering at 

 the apex, less than 5 mm. 



wide 14. M. cuspidata. 



Lemmas with conspicuous long awns. 



Leaf sheaths very broad at the base and 

 papery, loose, not closely investing 

 the stems. 

 Second glume 3-toothed; lemma 



pubescent at the top 17. M. trifida. 



Both glumes acute or acuminate ; lem- 

 mas pubescent only below 18. M. viresccns. 



Leaf sheaths not broad and papery, closely 

 investing the stems. 

 Spikelets on long slender pedicels. 



Second glume entire at the apex. 19. M. affinis. 

 Second glume sharply 3 to 5- 



toothed 20. M. subalpina. 



Spikelets on short stout pedicels, or 

 sessile . 

 Awns about 5 mm. long; stems 



stout; internodes long 21. M. acuminata. 



Awns about 20 mm. long; stems 

 slender, wiry; internodes 

 short 22. M. monticola. 



1. Muhlenbergia emersleyi Vasey, Contr. U. S. Nat. Herb. 3: 66. 1892. 

 MuJilenbergia vaseyana Scribn. Rep. Mo. Bot. Gard. 10: 52. 1899. 



Type locality: "Rocky Cafion, Arizona." 



Range: Western Texas to southern Arizona and adjacent Mexico. 

 New Mexico: Silver City; Mogollon Mountains; Santa Rita; Animas Valley; 

 Organ Mountains ; Dona Ana Mountains. Dry hills, in the Upper Sonoran Zone. 



2. Muhlenbergia porteri Scribn.; Beal, Grasses N. Amer. 2: 259. 1898. 



Mesquite grass. 

 Type locality: Texas. 



Range: Colorado and western Texas to California and Mexico. 



New Mexico: Mangas Springs; Albuquerque; Organ Mountains; Tortugas Moun- 

 tain; Mesilla Valley; Dona Ana Mountains; Jarilla; Arroyo Ranch. Hills and mesas, 

 in the Lower and Upper Sonoran zones. 



Mesquite grass receives its name from the fact that, in the southern part of the State, 

 where it is very common, it is nearly always found growing in the shade of mesquite 

 bushes, its slender, lax stems often clambering over them. Cattle are very fond of it 

 and will force their way into the mesquite to reach the grass. 



3. Muhlenbergia pungens Thurb. Proc. Acad. Phila. 1863: 78. 1864. 



Purple hair grass. 



Type locality: Colorado. 



Range: Utah and Nebraska to Arizona and Texas. 



New Mexico: Carrizo Mountains; Zuni Reservation; Chama River; Los Pilares; 

 on the San Juan; White Sands. Sandhills and on plains, in the Lower and Upper 

 Sonoran zones. 



