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COMPARATIVE ANALYSIS. 



BEOMUS. Large glume seven-ribbed ... 1 



Large glume three-ribbed . . . .4 



1. Summit of upper glume midway between its base and 



summit of third floret .... 2 

 Summit of upper glume midway between its base and 



summit of second floret . . . .3 



2. Florets and glumes hairy .... Mollis. 

 Florets and glumes not hairy . . . Racemosus. 



3. Twice width of outer palea considerably more than length 



of palea . . - . . Secalinus. 



Twice width of outer palea equal to length of palea . Arvensi*. 



4. Awns of florets much longer than calyx . . 5 

 Awns of florets much shorter than calyx . . .6 



5 Spikelets drooping, awns longer than the florets . . Sterilis. 

 Spikelets erect, awns equal in length to the florets . Diandrm. 



6 Lower floret about one-third longer than the small glume . Erectus. 

 Lower floret about twice the length of the small glume . Asper. 



TKISETTJM. Eadical leaves hairy ... 1 



Eadical leaves not hairy . . . Pratense. 



1. Ligule long and acute . . . . Pulescens. 



Ligule very short and obtuse . . . Flavescens. 



FESTUCA. Awns much longer than the florets . Eromoides. 



Awns much shorter than the florets . . .1 



1. Eoot fibrous, stem under the panicle rough . . Ovina. 



Root creeping, stem under the panicle smooth . Duriuscula. 



TRITICUM. Spikelets long, on short footstalks . . Sylvaticum. 



Spikelets short, without footstalks . . .1 



1. Stem rough ..... Cristatum. 

 Stem smooth . . . . . .2 



2. Awns rather longer than the florets . . . Caninum. 

 Awns very short, or wanting . . . .3 



3. Rachis rough ..... Repem. 

 Rachis smooth .... Junceum. 



LOLITJM. Florets awned, glume longer than the spikelet . Temulentum. 



Florets not awned, glume shorter than the spikelet . Perenne- 



