. On the natural history and classification of birds . ssed, that it must possessvery little strength. The pelicans bill seems dispro-portionably large, but it possesses little or no strength :the under mandible is so thin that the bones are pliable;and it is one of the vulgar tricks of the keepers intravelling menageries, to show the spectators how it maybe turned into a cap or bonnet. (6l.) There are some other modifications in theform of the bill, which will not strictly come under theforegoing definitions; but which, although compar-atively rare, deserve our attention. The chief of thesema
. On the natural history and classification of birds . ssed, that it must possessvery little strength. The pelicans bill seems dispro-portionably large, but it possesses little or no strength :the under mandible is so thin that the bones are pliable;and it is one of the vulgar tricks of the keepers intravelling menageries, to show the spectators how it maybe turned into a cap or bonnet. (6l.) There are some other modifications in theform of the bill, which will not strictly come under theforegoing definitions; but which, although compar-atively rare, deserve our attention. The chief of thesemay be distinguished by the following names : — ; 2. Cuneated, or wedge-shaped; , or sword-shaped; 4. Spatulate, or spoon-shaped ; 5. Recurved; and, 6. Truncated. Each ofthese forms will now be separately considered. (62.) I. A Semi-raptorial bill is where the upper man-dible terminates in a strong, sharp, abrupt, and for-midable hook, obviously intended for rapine, but yetunassisted by those tooth-like processes, or notches,. which we see in the hawks, shrikes, and fissirostralbirds. It is obvious that this powerful hook acts as a F 2 68 ON THE CLASSIFICATION OP BIRDS. strong claw, and is somewhat analogous to the talons ofan eagle, by being struck into the prey. It certainly isnot used, like that of the true rapacious order, for tearingthe food in pieces, for it is well known that pelicans,in a state of confinement, preserve their natural habitof swallowing their food entire, and we have evidenceto prove that the whole of the cormorant family do thesame. Indeed, the great expansive power of the throatof both these genera, manifestly constructed for receiv-ing food in such a state, places the fact beyond owls, which represent the Natatorial order (whereinthis structure is only found), show it in its incipientstate; for, although their upper mandible is greatlyhooked, there is no appearance of the notch so universalamong the falcons. (63.) I
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