AVENE.E. 371 



Texas, Colorado, Ctiliforniii to Alaska. 



9. D. gracilis Vasey, Coult. Bot. Gaz. 10: 224 (1885). 

 Culms smooth, slender, 30-70 cm. high. Ligule 4-5 mm. 



long, acuminate; blades smootli, filiform, 6-10 cm. long. Pani- 

 cle 15-20 cm. long, lax and open, rays mostly in twos, the lower 

 ones 6-10 cm. long, slender, flower-bearing to or below the middle. 

 Empty glumes equal, linear-lanceolate, tinged with purple and 

 brown, 3-nerved, and about 3.5 mm. long; florets overla])piug for 

 one-third their length, an awn starting near the middle of each 

 floret, 5-6 mm. long, rachilla villous; floral glume 1.5 mm. or 

 more long, 1 mm. wide, 4-toothed, faintly nerved; palea as long as 

 its glume, narrow, incurved, ciliate above, 2-toothed. Grain com- 

 pressed, half oval, 1 mm. long. 

 California, Orcutt in 1884. 



10. D. elongata (Hook.) Munro. Benth. PI. Hartw. 342 

 (1857). Aimelomjafa Hook. Fl. Bor. Am. 2: 243 (1840). 



Culms very slender, often tufted, 20-60 cm. high. Ligule 

 acute, 4 mm. long; blades very narrow, 4-15 cm. long, mostly 

 smootli. Panicle narrow, simple or branching, about one-third as 

 long as its culm, rays capillary, scabrous, appressed, bearing spike- 

 lets above the middle. Empty glumes equal, oval-lanceolate or 

 linear-lanceolate, 3-4 mm, long, 3-nerved, longer than the florets, 

 green and scabrous on the keel; florets 2 mm. long, shining, over- 

 lapping for one-third or more of their length, silky hairs reaching 

 to the middle; floral glume broad, nerves very obscure or none, apex 

 apparently 5-toothed or lacerate, the slender awn starting near or 

 below the middle and twice the length of its glume; terminal part 

 of the rachilla about two-tliirds as long as the upper floret; palea 

 about as long as its glume, 2-tootlied, curved. Grain 1.5 mm. 

 long, flattened, straight on the outside, grooved. 



Jones for U. S. Dept. Agricul. 4591. 



British America to California. 



Var. ciliata Vasey, iued. 



Culms 60-80 cm. high; ligule 8 mm. long; blades less involute 

 and softer; panicle often 30 cm. long; awns longer. 



Oregon, Hoioell; California, Dr. Anderson. 



