The Feet of Birds. 49 



will in some cases be seen to vary from this description, it will 

 on the whole be found to be typical of the division to which it 

 refers. Thus we see the birds of prey armed with feet and 

 claws which form the most powerful weapons for striking down 

 and carrying off their victims. The perchers provided with so 

 exquisite a piece of mechanism as to enable them to seize, 

 balance, and support themselves on a branch with ease. The 

 ground-birds furnished with limbs so strong, muscles so powerful, 

 and feet so adapted for the purpose, as to make them seek safety 

 in running when beset by foes. The waders, though often unable 

 to swim, raised high out of the water in which they seek their 

 food by the length of their legs, and enabled by their spreading 

 toes to run lightly over water-plants and the softest mud without 

 danger of sinking in. The swimmers supplied with feet and 

 legs serving them for oars and rudders, whereby to impel for- 

 wards their bodies on the waves, or to seek their food far below 

 the surface of the water. These are all instruments so exactly 

 and so perfectly adapted to their respective uses, that we can 

 conceive nothing more applicable ; and they are plain and easy 

 marks to us for ascertaining the general habits and classified 

 position of any bird we observe. Our examination of the subject 

 might well stop here ; but, before concluding this paper, I would 

 call attention to a few remarkable instances of structure in regard 

 to the feet, as displayed by some particular species. 



The Osprey alone, of all the family Falconidce, lives entirely 

 upon fish, and the nature of its prey being therefore different 

 from that of its congeners, it requires and is furnished with feet 

 peculiarly fitted for seizing and holding securely the slippery 

 denizens of the deep. In the first place, in lieu of the long 

 feathers which commonly clothe the thighs of the falcon race, 

 short ones are substituted, which leave more freedom for action 

 in the water ; then the outer toe is reversible, and can at pleasure 

 be turned backwards, so that, as Yarrell tells us, it is the custom 

 of the bird to < seize the prey across the body, placing the inner 

 and outer toes at right angles with the middle and hind toes ; 

 and, digging in the claws, to hold the fish most firmly by four 



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