502 POACE^. 



lanceolate, 5-12-flowered, rachilla pubescent with short silky hairs; 

 glumes with prominent green nerves, first empty glume 4 mm. 

 long, ovate, 3-uerved, second 5.5 mm. long, oval when spread, 

 7-nerved; floral glume pubescent at the base, 7-nerved, ovate- 

 cuneate, apex obtuse; palea softly pubescent, nearly 4 mm. long. 

 Anthers ovate, 0.7 mm. long. 

 Texas, JSfealley for Nat. Mus. 



7. M. diffusa Pursh, Fl. Am. Sept. 1: 77 (1814). M. altissima 

 Walt. Fl. Car. 78 (1788), not L. M. mutica var. difftisa A. Gray, 

 Man. Ed. 2:558 (1856). 



Culms rather stout, 80-120 cm. high. Slieaths about the 

 length of the iuternodes ; ligule white, lacerate, 4 mm. long ; 

 blades 5 in number, flat, slightly scabrid, about 15 cm. long, 6-8 

 mm. wide. Panicle linear or becoming oval, 20 cm. long, rays 

 mostly in threes, the longest 5-7 cm. long, bearing a few spikelets 

 above the middle. Spikelets borne on weak flexuose or bent pedicels, 

 2-3-flowered with one or more rudiments, longest joint of rachilla 

 2.5 mm. long ; first empty glume 7 mm. long, broadly oval, 5-7- 

 nerved (if 7-nerved the lateral nerves ol)scure), second obovate- 

 oblong, 9 mm. long, scarcely acute, 5-nerved; floral glume 9 mm. 

 long, elli])tical, 7-nerved above, 21-nerved below; palea spatulate- 

 oval, 7 mm. long. 



Pennsylvania, T. 0. Porter ; Kentucky, C. W. Short ; New 

 Mexico, m-ight 2062. 



Pennsylvania, Texas, Arizona, and Mexico. 



Var. nitens Scribn. Proc. Phila. Acad. 44 (1885). 



" It differs from the species in its more leafy culms, narrower 

 leaves, more densely flowered panicle, and in its much broader and 

 more unequal outer glumes, the second one being nearly as long as 

 the spikelet." Scribner, 1. c. 



Texas, Eeverchon, Curtiss 3464a, Nealley; New Mexico, Wright 

 2063, Jones 4334 ; Arizona, Pringle, Rothrock 805 ; Eocky 

 Mountains, Hall d Ilarlmur 228. 



Texas, Nebraska, Colorado, Arizona. 



8. M. parviflora (Porter) Scribn. Mem. Torr. Club, 5 : 50 

 (1895). M. mutica var. ])arvijiora Porter, Porter & Coulter, Fl. 



