COMPAEATIVE ANALYSIS. 



231 



POLYPOGON. 



Awns as long as the calyx, root creeping 

 Awns mucli longer ttan the calyx, root fibrous 



Littoralis. 

 Monspeliensis. 



Calamageostis. 



Corolla with a terminal awn, panicle loose . Laneeolata. 



CoroUa with a dorsal or basal awn, panicle close . 2 



Plowers without a rudiment of a second floret . Epigejos. 



Flower with a minute pedicel, bearing a tuft of hair 



(a rudiment of a second floret) . . .3 



Hairs as long as the coroUa, awn near the base . Lwpponica. 

 Hairs shorter than the coroUa, awn above the middle . Stricta. 



Ageostis. 



Inner valve of corolla wanting, or minute . . 2 



Inner valve of corolla not minnte . . 3 



Leaves linear, awn dorsal .... Canina. 



Leaves setaceous, awn basal . . . Setacea. 

 Awn very long and terminal, florets with a barren pedicel 



at base ..... Spica-venti. 



Awn none, or short and dorsal, no barren pedicel . 4 



Ligule short and truncate, outer valve of corolla three-nerved Vulgaris. 



Ligule oblong, outer valve of corolla five-nerved . Alia. 



Catabkosa. 



Branches whorled 



AlEOCHLOA. 



Glumes shorter than the florets 



AlRA. 



1. Awn clavate .... 

 Awn not clavate 



2. Leaves linear, awns not or but little longer than 

 Leaves setaceous, awns longer than corolla 



3. Awn basal, branches rough 

 Avm dorsal, branches smooth 



4. Florets hairy at base 

 Florets scarcely hairy at base . 



5. Panicle close, awn basal 

 Panicle spreading, awn dorsal 



Melica. 



1. Panicle drooping, florets not longer than the calyx 

 Panicle erect, florets much longer than the calyx 



2. Spikelets with two perfect florets 



. Aquatica. 



. Cristata. 



Caneseens. 



2 



corolla 3 



4 



Ccespitosa. 



Alpma. 



. Flexuosa. 



5 

 , Frtscox. 

 . Caryophyllea. 



. 2 

 3 

 . Nutans. 



