﻿146 ON THE CLASSIFICATION OF BIRDS. 



duced by claws which both terminate in remarkably 

 acute points, appears at first exceedingly perplexing, 

 and may well claim our attention. The explanation 

 appears to be this : 1 . the claw of the sparrow-hawk, in- 

 dependent of its acute point, has two sharp cutting 

 edges beneath, one on each side, which are continued 

 to the tip ; by this structure it becomes a three-sided 

 weapon, and enters the flesh immediately upon the least 

 force being applied ; 2. the claw reaches its termin- 

 ation very gradually, so that its power of penetration is 

 doubly augmented. No such characters belong to the 

 claw of the Buphaga ; it has no lateral cutting edges, 

 although the sides (occasioned by the flatness of its 

 under part) are bluntly angulated ; added to which the 

 termination is remarkably abrupt, so that the extreme 

 point would act as a little hook, without penetrating 

 farther. This, in fact, is established by the experiment 

 just alluded to, and which it is in the power of any one, 

 having skins of the birds in question, to verify. It is 

 quite obvious that if the claws of the Buphaga would 

 not excite pain upon the human hand, it would have 

 no such effect upon the thick hide of an ox, but rather 

 excite an agreeable irritation, like that which is felt on 

 scratching an inflamed part of the human body. The 

 large Acari of tropical countries are well known to 

 create sores, and the gentle irritation round these parts, 

 according to every principle of analogy, would have the 

 same effect upon the skin of the ox, as upon that of 

 the human species. On attentively considering all these 

 circumstances, we feel persuaded that the Buphaga riot 

 only seeks its chief food from the Acari and other 

 parasitic insects infecting cattle, but that it actually 

 climbs about their bodies for that purpose, in all direc- 

 tions ; this latter belief being sanctioned by the great 

 development of the hind claw, and its very rigid, 

 although not pointed, tail. 



(126.) There is only one other modification of foot 

 which seems also belonging to the scansorial type ; this 



