* 
Mr. Woops on the Genera of European Grasses. 15 
usually embraces the base of the inner; but in Phalaris and Achnodonton, by 
the help of the position and direction of the lateral nerve, they have the 
appearance of being almost valvular. The only genera in which the outer 
glume is the largest are, Milium, Achnatherum, Gastridium and Calama- 
grostis and Deyeuxia. The substance of the glumes is sometimes of use 
in determining genera; but on this head there seems to be a great dif- 
ference in the terminology of different authors, and perhaps few authors 
are always perfectly consistent with themselves, expressing the same cha- 
racter by different words in different places, and even different characters 
apparently by the same word. Thus the glumes of Milium are membranous 
according to Kunth and Gaudin, herbaceous, if we consult Hooker. The 
paleæ of the same plant are subcoriaceous in Kunth, cartilaginous in Gaudin, 
Kunth applies alike the term membranaceous to the paleæ of Alopecurus and 
of Phalaris, though the consistence is certainly very different. I find these 
parts of Grasses described by different authors as carnose, cartilagineæ, co- 
riaceæ, chartacee, papyraceæ, herbaceæ, membranaceæ, scariose, hyalinæ, 
tenerrime membranaceæ, and with different compounds of these terms, I 
distinguish j 
Finwv. Very thin and transparent. The paleæ of most species of Andropo- 
gon and Sorghum may be taken as examples of this degree of solidity. The 
palea also of Anappia, and the inner palea of the neutral floret of Oplismenus, 
and the inner palea of some species of Agrostis and of other Grasses. 
ScanrosE. Transparent, like the preceding, but firmer: it exists in the 
palez of Phleum, and of many other Grasses, and in the glumes of Polypogon 
and Stipa. . i 
Mempranous. Still firmer; translucent but not transparent, and often 
coloured (but not green). We find it in the glumes of Agrostis and Arundo, 
in the palez of Poa nemoralis and Glyceria aquatica. 
We may use the compound term Mzunhaxo-scaRlosk for an interme- 
diate state, as in the glumes of Deschampsia cespitosa and of Avena pubes- 
cens. : 
Herpaceous. Green, and nearly of the texture of a leaf, as in the barren 
floret of the Paniceæ. This perhaps differs more in colour than in substance 
from membranous. 
