140 THE TRUE GRASSES. 



Empty glumes slightly 

 unequal. 



228. Catabrosa. 

 XX Empty glumes very 

 unequal, lower almost 

 wanting. 



229. Sphenopus. 



<] < < Panicles with very short 

 but spreading and some- 

 what stout branches. 

 Glumes indurated. 



23O. Cutandia. 



** Flowering glumes 3-5- to many- 

 nerved, with two or more of the 

 upper glumes empty ; appressed 

 and frequently enclosing or envel- 

 oping each other, 

 t The sterile upper glumes form- 

 ing together at their tips a tuft 

 of awns. 

 O Leaves narrow-linear. 



231. Ectrosia. 

 O O Leaves broad-lanceolate. 



240. Lophatherum. 

 ft Sterile glumes not awned. 



O Flowering glumes flabelli- 

 form, white-membraiiaceous, 

 and corolla-like. 



234. Anthochloa. 



O O Flowering glumes of some 

 other form. 



< Spikelets laterally com- 

 pressed ; glumes sharply 

 keeled. 



X Empty glumes persist- 

 ent; flowering glumes 

 5-nerved. 



233. Heterachne. 



XX Spikelets deciduous as 



a whole ; flowering 



glumes three-nerved. 



232. Harpachne. 



