48 Mr. Woods on the Genera of European Grasses. 



Secale seenis better separated from Triticum on the small and inefficient 

 glumes, and on the tapering form of the outer palea, than on the number of 

 florets. 



I have not before me a sufficient number of species to affix new limits to 

 the genera Elymus and Hordeum, but I am inclined to find the distinction in 

 the setaceo-aristate glumes, and perhaps in the long awns or setae of the latter 

 genus. The number of florets does not seem to affbrd a satisfactory line, 

 since E. europceus, which is described as two-flowered, is certainly more com- 

 monly met with, as is observed by Sir W. Hooker, having only one, and indeed 

 I have never found in the specimens I have examined two perfect florets. The 

 rudiment of the second is usually a mere stalk, and the whole structure of 

 the flower exactly like that of Hordeum pratense. E. crinitus has usually a 

 distinct palea, perhaps two, to the second floret, but as far as I have seen, it 

 is always empty. These two species, and probably two or three more, not 

 natives of Europe, would on my scheme be joined to Hordeum; but I do not 

 know how far it would be possible to draw a line throughout the genus in ac- 

 cordance with the habit of the plants. 



Pappophore^. 



This is a very small tribe, containing in the whole only 7 genera, and 28 

 species. In Europe we liave only 1 species, which is particularly interesting, 

 as it enables our Flora to yield an example of every tribe into which the 

 Grasses have been divided. The leading characters seem to be the thin and 

 entire glumes united to coriaceous and many pointed paleae. 



Echinaria. Spiculse sessile, crowded, placed all round the rachis, 2 — 4-flow- 

 ered, of which not more than the two lower are perfect. Glumes ending 

 in a seta. Outer palea with five, inner with two points. Seed hairless. 



ROTTBOELLIACE^. 



These differ from the Hordeacece in having only one perfect floret placed 

 edgewise on the spike, which is sometimes one-sided, sometimes equal all 

 roimd. According to Kunth, tlie second imperfect floret, where it occurs, 

 is in some genera above, and in some below the perfect one. Is this to be 

 considered as an indication that he has united two tribes into one ? or that 



