AGROSTIDE.E. 191 



C. Empty glumes saccate at tlie base, mucli longer 



than the floral glumes (37 



C. Empty glumes uot saccate at the base. . . (d) 

 d. Empty glumes subequal, louger than the floral 

 glume, each abruptly terminating in a short 



awn; inflorescence spikelike 50 



d. Empty glumes subequal. longer than the floral 

 glume, usually bifld, each terminating in a 

 slender awn; inflorescence spikelike, often 



interrupted 02 



d. Empty glumes slightly unequal, a little 

 shorter than the floral glume, acute; inflores- 

 cence spikelike 55 



d. Empty glumes or inflorescence or both un- 

 like those of (e) 55, 56, 62 



6. Plant annual, dwarf, 5-0 cm. high, empty 

 glumes minute, awnless; spikelets 1.5 

 mm, lo7ig, awnless. Stamen 1. . . . 5!) 

 e. Plant annual, taller, empty glumes plu- 

 mose "^2 



e. Plants usually much larger. Stamens 2-3; 

 grain dehiscent, seed escaping, at least 



when wet, glumes all awnless 00 



e. Plants unlike 59, 00 (f) 



f. Floral glume bearing a prominent awn 

 2-4 times its own length, a little below 



the apex (g) 



g. Awn twisted g3 



g. Awn not twisted 71 



f. Floral glume without an awn or only a 



short slender awn (o-) 



g. Callus or prolongation of the rachis 

 bearing a tuft of hairs, at least one- 

 third as long as the floral glume. . (i) 

 i. Floral glume and palea thin, 

 membranous OS 



