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COMPARATIVE ANALYSIS. 



Dr. Parnell gives the following analysis: 



ALOPECURTJS. Stem rough .... Agrestis. 



Stem smooth . . . .1 



1. Upper leaf much shorter than its sheath . . 2 

 Upper leaf about equal in length to its sheath . 3 



2. Awn projecting more than half its length beyond floret Alpinus. 

 Awn projecting not more than a third beyond floret Pratensis. 



3. Awn projecting half its length beyond floret . Geniculatus. 

 Awn not projecting beyond floret . . . Fulvus. 



PHLETTM. Glumes awned .... 1 



Glumes acute, not awned . . .2 



1. Awn not half the length of glume . . Pratense. 

 Awn more than half the length of glume . Alpinum. 



2. Floret not half length of calyx . . . Arenarium. 

 Floret more than half length of calyx . . Michelii. 



PHALARIS. Base of floret with two membranous valves Canariensis. 



Base of floret with two hairy valves . Arundinacea. 



HORDEUM. Glumes of middle spikelet fringed . Murinum. 



Glumes of middle spikelet not fringed . 1 

 1. Inner glume of lateral spikelet very much dilated on one side Maritinum. 



Glumes not dilated . . . Pratense. 



AGROSTIS. Ligule of upper sheath very short . . Vulgaris. 



Ligule of upper sheath long . . .1 



1. Floret of two palea3, sheaths roughish . . Alia- 



Floret of one palea, sheaths smooth . . . Canina. 



CALAMAGROSTIS. Hairs shorter than floret . . Stricta. 



Hairs longer than floret . . Epigejos. 



MELICA. Calyx with one floret and rudiment of second Uniflora. 



Calyx with two florets and rudiment of third . Nutans. 



MOLINIA. Outer palea five-ribbed . . . Depauperata. 



Outer palea three-ribbed . . . Ccerulea. 



HOLCTJS. Awn of floret smooth . . . Lanatus. 



Awn of floret rough . . . Mollis. 



AIRA. Awns not protruding beyond the florets 1 



Awns protruding considerably beyond the florets . 2 



1. Awn arising from little above base of palea . Ccespitosa. 

 Awn arising from little above centre of outer palea . Alpina. 



2. Sheath of leaf rough from above downwards . Flexuosa. 

 Sheath of leaf rough from below upwards 3 



3. Panicle spreading .... Caryophillea. 

 Panicle close . . Pracox. 



