470 MISC. PUBLICATION 200, U. S. DEPT. OF AGRICULTURE 



Figure 1008.— Aegopogon tenellus. Plant, X H; group of spikelets, X 5; lateral spikelets and central 

 spikelet, X 10. (Pringle 1407, Mexico.) 



Lemmas about 1.5 mm long; panicle oblong, the axis relatively long. 

 Sheaths and blades glabrous; lemmas awnless or nearly so. 



3. L. VIRGATA. 



Sheaths and blades sparsely pilose; lemmas awned__ 4. L. domingensis. 

 Plants annual. 



Sheaths papillose-pilose; first floret not longer than the second glume; spike- 

 lets mostly 1 to 2 mm long 5. L. FILIFORMIS. 



Sheaths smooth or scabrous, not pilose; spikelets more than 2 mm long. 

 Lemmas awned, awns sometimes minute. Culms freely branching. 



Lemmas viscid on the back; panicle oval, usually less than 10 cm long, 

 the longer branches usually less than 5 cm long; second glume 1.5 



mm long 6. L. viscida. 



Lemmas not viscid; panicle more than 10 cm long, the longer branches 

 usually as much as 10 cm long; second glume 3 mm long. 



7. L. FASCICULARIS. 



