THE GRIFFON VULTURE. 99 



ters by which the family of Vultures are distinguished 

 from all other Birds of Prey. They consist in the 

 entire or partial denudation of the head and neck, the 

 latter of which is much elongated ; the lateral position 

 of the nostrils in a generally broad and powerful bill, 

 curved only at its point, and clothed at its base by an 

 extended cere ; the nakedness of the tarsi, which are 

 covered only with small reticulated scales; and the 

 strong thick talons, somewhat blunted at the points, 

 but little curved, and scarcely, if at all, retractile. Of 

 these characters the most obvious is the absence of 

 feathers to a greater or less extent on the head and 

 neck, a mark of distinction which, like all the rest, is 

 closely connected with the habits of the birds. Thus it 

 has been pointed out that in other groups a falling off 

 or thinning of the feathers is the frequent result of 

 feeding upon flesh especially when in a state of decay. 

 The bareness of these parts in the Vultures enables 

 them moreover to burrow in the putrid carcasses on 

 which they prey without risk of soiling their plumage. 

 Their largely extended nostrils and the great internal 

 developement of these organs would seem to be of mani- 

 fest use in guiding the Vultures to their prey, which 

 they are generally believed to scent from an immense 

 distance. It has, however, been lately maintained by 

 a most acute observer of the habits of birds, Mr. Audu- 

 bon, that this belief, which has been entertained from 

 the earliest antiquity, is founded in error, and that the 

 Vultures are directed to their prey by sight alone, the 

 lofty pitch at which they fly and the surpassing excel- 

 lence of their vision enabling them to detect it at an 

 almost inconceivable distance. Several of the experi- 

 ments brought forward by that gentleman in support of 

 his hypothesis, appear at first sight almost decisive of 

 the question ; but we cannot consent to abandon the 



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