162 



Fig. 15G. DESCHAMPSIA ELONGATA ( Hook.j Munro in Benth. PI. Hartwc?. 

 342. 1857. {Aira dongata Hook. Fl. Bor. Am. 2 : 243. t. 288. 1840.) SLENDER 

 HAIR-GRASS. -A slender perennial 3-12 dm. (p-io) high, with narrow panicles 

 1.0-3.5 dm. (G'-IJ') long. Leaf-blades Involute 2-15 cm. (I'-o') long ; ligule mem- 

 branaceous, nearly acute, 2-4 mm. (l"-2") long, decurrent. Spikelets {a) about 

 4 mm. (2'0 long, with nearly equal, very acute 3-nerved, emptv glumes, exceed- 

 mg the florets {h); first flowering glume about 2 mm. (I'o'long. irregularly 

 5-toothed at the apex, with a slender awn from near the base twice its own 

 length or more.— Montana to British Columbia and southward on the Pacific 

 Slope to Mexico. May to August. 



