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COMPAEAIIVE ANALYSIS. 



BncETtrM. — Inflorescence racemed, approacting to a spike Loliaceum. 



Inflorescence panicled . . .1 



1. Panicle simple . . . Pratense. 

 Panicle compound . . . .2 



2. Awn considerably shorter than palea . . Elatius. 

 Awn considerahly longer than palea . . Giganteum. 



BEOMtrs. — 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. 

 Plorets and glumes not hairy . . Raoemoaus. 



3. Twice width of outer palea considerably more than 



length of palea . . . Secalinus. 

 Twice width, of outer palea equal to length of palea 



4. Awns of florets much longer than calyx . 

 Awns of florets much shorter than calyx 



5. Spikelets drooping, awns longer than the florets 

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



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

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



Teisetdm. — Kadical leaves hairy . . .1 



Eadical leaves not hairy . . Pratense. 



1. Ligule long and acute . . . Pulescens. 



Ligule very short and obtuse . . . Flavescens. 



Pestuoa. — Awns much longer than the florets . Bromoides. 



Awns much shorter than the florets . 1 



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



Eoot creeping, stem under the panicle smooth . Duriuscula. 



Teiiicum. — Spikelets long, on short footstalks . Sylvatieum. 



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. Eachis rough ..... Repens. 

 Rachis smooth .... Juneeum. 



LoLiiTM.— Horets awned, glume longer than the spikelet 



Plorets not awned, glume shorter than the spikelet 



Perenne. 



