THE TRIBES AND THEIR GENERA. 



49 



A vex a. Panicles loose. Spikelets with two or more florets. 

 Rachilla extending beyond upper floret. Glumes unequal, mem- 

 branous, lanceolate, acute, ventricose, loose, persistent, awnless. 

 Outer palea slightly smaller, with 

 lateral veins, ending in two points, 

 awned ; awn dorsal, kneed, twisted. 

 Lodicules two. Stamens three ; 

 filaments thin, capillary. Ovary 

 hairy at apex. Stigmas protruding 

 above the base or middle of the 

 spikelet. Grain fusiform, deeply 

 grooved, hairy at apex, enclosed 

 by the palece. Starch grains com- 

 pound. 



Species. A.faiua, 41. 



A . pratensis, 42 . 

 A . ftavescens, 43 . 



Avena pratensis. 

 Floret. For Spikelet see p. So. 



Arrhenatherum. Spikelets upright. Florets two, upper 

 perfect, lower male and awned. Rachilla prolonged beyond upper 



floret. Glumes unequal, membranous, 

 persistent. Outer palea of upper 

 floret awned from the point or awn- 

 less. Outer palea of lower floret 

 awned from below the middle, awn 

 long, bent, and twisted. Inner paleae 

 herbaceous, ending in two points. 

 Lodicules two. Stamens three. 

 Ovary hairy at apex. Stigmas pro- 

 truding above the base or middle 

 of the spikelet. Grain oblong, not 

 grooved, hairy at apex, enclosed by 

 the paleae 



ArrltenathctiDii avenactum. 

 Floret. For Spikelet see p. 77. Species. A . UVCnaCClim, 44. 



