THE BEAK. 29 



been observed, that those possessing it are more noble 

 and courageous than others. Thus the Shrike, or 

 Butcher Bird, although its 

 usual food consists of beetles 

 and insects, will not only 

 bravely defend itself, but oc- 

 casionally attack birds far su- 

 perior in size ; and is a perfect 

 terror to the smaller species, 

 who flutter round their assail- 

 ant uttering the most piercing 

 cries, as if they wished to give -Bearded Vulture. 

 notice of the intruder's approach. The bill of the Parrot 

 is also hooked, but is at the same time unfitted for the 

 uses to which it is applied by the birds just mentioned, 

 curving and overlapping the lower bill so much, that if 

 the lower bill only had motion, the bird could scarcely 

 open its mouth sufficiently wide to receive food; yet 

 neither the hook nor the overlapping could be omitted, 

 since it is by the beak that Parrots so readily climb; for 

 which purpose it is therefore fitted, as well as for break- 

 ing nuts and other hard substances on which they feed. 



The way by which the Parrot's beak is able to answer 

 both purposes is this: the upper mandible, which in 

 other birds forms one uniform piece or continuation of 

 the skull, is united to the bone of the head by a peculiar 

 membrane placed on each side of it, enabling the bird 

 to lift or depress it at pleasure. The muscular power 

 of this contrivance is very great, for the truth of which 

 all who have incautiously exposed their fingers to the 

 bite even of a Paroquet will readily vouch. 



There is a bird, sometimes found in this country, 

 called the Cross-bill, from the singular construction of its 

 beak, the mandibles of which, instead of shutting toge- 

 ther like those of other birds, cross each other; at first 

 sight this might be supposed to be an accidental defor- 

 mity, and that the poor bird must have great difficulty 

 in picking up its food. But this is by no means the 



