﻿EXTERNAL ANATOMY. BILL. 6*7 



thick, does not appear to be very solid or compact ; it is 

 not improbable that its inside is of a cellular texture, 

 something analogous to that of the toucans, and connected 

 with the very extraordinary situation of the nostrils. 



(60.) The enormous size of the bill, as seen in the 

 toucans and hornbills (Buceridw), shows that this quality 

 is not necessarily accompanied by strength, for the in- 

 ternal structure, in both families, being cellular, the 

 bill is not only very light, but may be broken with ease. 

 That of the awks (Alcadce), when viewed in profile, 

 seems to be very large, but it is, in fact, so thin, or 

 in other words so compressed, that it must possess 

 very little strength. The pelican's 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 in 

 travelling menageries, to show the spectators how it may 

 be turned into a cap or bonnet. 



(6l.) There are some other modifications in the 

 form of the bill, which will not strictly come under the 

 foregoing definitions ; but which, although compar- 

 atively rare, deserve our attention. The chief of these 

 may be distinguished by the following names : — 1. 

 Semi-raptorial ; 2. Cuneated, or wedge-shaped ; 3. 

 Falcate, or sword -shaped ; 4. Spatulate, or spoon- 

 shaped ; 5. Recurved ; and, 6. Truncated. Each of 

 these 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 yet 

 unassisted by those tooth-like processes, or notches, 



which we see in the hawks, shrikes, and fissirostral 

 birds. It is obvious that this powerful hook acts as a 



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