GENERA OF GRASSES OF THE UNITED STATES. 

 7. CHLORIDEAE, THE GRAMA TRIBE. 



82. LEPTOCHLOA Beauv. 



171 



Spikelets 2 to several flowered, sessile or short-pediceled, approxi- 

 mate or somewhat distant along one side of a slender rachis, the 

 rachilla disarticulating above the glumes and between the florets; 

 glumes unequal or nearly equal, awnless or mucronate, 1-nerved, 



FIG. 100. Aegopogon tcnellus. Plant, X I ; group of spikelets, X 5 ; lateral spikelet, 

 X 10 ; central (long-awned) spikelet, X 10. 



usually shorter than the first lemma ; lemmas obtuse or acute, some- 

 times 2-toothed and mucronate or short-awned from between the 

 teeth, 3-nerved, the nerves sometimes pubescent. 



Annual or perennial grasses, with flat blades and numerous spikes 

 or racemes scattered along a common axis forming a long or some- 



