ee! 
* ad ¢ 
116 ON THE CLASSIFICATION OF EI 
fact, which is to tum these seeds into nourishm 
If there was little variation in the size or strength 
the bills of the tanagers, the inevitable consequence 
would follow, that they would only be able to feed 
upon seeds or nuts varying but very slightly in thet 
size and hardness: and hence it would follow, that 
innumerable other sorts, which either did not come up 
to this standard, or much exceeded it, would be left 
untouched, and, as food to the animal world, perfectly 
useless ; at least, so far as we can conjecture. To pre- 
vent, therefore, such a waste of her vegetable aliments, 
nature has created in the finches a vast family of ——_ 
expressly for the purpose of subsisting upon them; and 
that these birds should be qualified to partake of all the 
different sorts, from the softest to the hardest, she has 
given to these creatures a corresponding variety in the : 
shape and strength of their bills. We are much 
strengthened in this hypothesis, by observing something 
of the same principle in operation, although, upon ¢ 
more limited scale, among the finches of Europe. How 
great, for instance, is the disparity of size between the 
bill of our hawfinch, greenfinch, and linnet; and yet 
these birds, so far from belonging, as is generally sup- 
posed, to shi as distinct and even remote genera, actually 
LZ follow each other (according 
to our analysis of their affi- 
nities), without the least inter-= 
ruption, as subgenera. Ever 
one, in fact, must perceive the 
close relation of the common — 
linnet (Linaria, fig. 164. a), to 
the green linnet (Chloris, b), 
and this again to the hawfinch — 
‘(Coccothraustes, c), with whiel 1 
it might, perhaps, be equally as: 
: sociated, as only a slightly aber- 4 
2 Lz rant species. Such a dispari 
in ate to the bills can scarcely be berneny in any othe r 
groups in ornithology. | 
: 
j 
‘ 
ee — 
——— EZ 
== 
