BILLS OF THE SYNDACTYLI. 199 



The bill in all of them is remarkable for the wide- 

 ness of its gape, and the breadth of the mandibles at 

 their bases; and it is sometimes provided with a 

 viscid secretion to which the insects adhere, and at 

 others with moustaches, in which they are caught, or 

 at least prevented from escaping out of the mouth. 



The bill of the common goat-sucker is probably 

 the most typical of the whole, at least it is more ex- 

 clusively used in preying ; as the bird not only feeds 

 in the twilight, but flies with the eyes in such a 

 position as that they can be of little or no use. 



BILLS OF THE SYNDACTYLI. 



The bills of the syndactylous birds also differ consi- 

 derably in their forms, because the food differs in kind ; 

 and there is no doubt that it was on account of this 

 difference of the food that Cuvier named this division 

 after the structure of the feet, and not that of the bills, 

 for the kind of food is the principal ground of his 

 arrangement. But in the case of birds the kind of 

 food is not so descriptive of the whole character as in 

 the mammalia, because the form of the bill depends 

 also upon the manner in which the food is arrived at. 



In the birds which should properly belong to this 

 division, the prey is arrived at on the wings, though 

 Cuvier, from having taken the united toes as the 

 general character, has included in it the hornbills, 

 which, in some of the species at least, are as truly 

 omnivorous as the crows, feeding on carrion, and of 

 course feeding on the ground, not on the wing. 



Leaving these out, there remain four genera, all of 

 which have the bill long, and catch their prey by the 

 snap, or quick compression of the mandibles against 

 each other. The bee-eaters (merops) have the bill 

 rather long, tapering to the point, slightly curved in 



