BIRDS. ®9 



The throat is very wide, and the swallowing powers con- 

 sequently great. Whatever is offered to it is first worked 

 about between the hucje mandibles, and then gulped entire. 

 Should the morsel swallowed be so large as to produce any 

 feeling of discomfort, it is immediately disgorged, and re- 

 swallowed after having undergone a little additional masti- 

 cation in the bill.* 



Adopting, as we have hitherto done, the leading divisions 

 of the system expounded by Baron Cuvier, the next order 

 is that of the Scansorial birds, or climbers, of which one 

 of the most characteristic external marks consists in the. 

 structure and position of the toes, which are usually placed 

 two before and two behind. From this result considerable 

 strength and tenacity of grasp, which enable the species so 

 constituted to adhere to the bark of trees, however vertical 

 their direction, and even in some eases to run along the lower 

 surface of horizontal branches with as much ease and safety 

 as others execute such ordinary movements as seem less op- 

 posed to the laws of gravitation. It is no doubt true that 

 many species, such as the cuckoo in which the toes are in 

 pairs, or yoke-footed, as M. Temminck has tenned it, do not 

 climb ; while it is equally true that several other species (such 

 as the creeper, C. familiaris), which are constant and accom- 

 plished climbers, are yet excluded from this order on ac- 

 count of the structure of their feet ; and that, consequently, 

 the denomination cannot be applied in its most rigorous 

 sense, as alike characteristic and inclusive. The ordinal 

 characters, considered in their generality, are in fact seldom 

 so precise and natural as to admit of no exceptions ; and 

 it is questionable whether a title should be immediately 

 changed upon the discover)' of every species which rnay 

 not coincide with its most rigorous interpretation. It is 

 not very easy, indeed, to understand how this alteration can 

 in every case be effected, merely upon the consideration of 

 a single character, without producing greater inconve- 

 niences than those which it is intended to obviate. In the 

 zygodactylous genus Galbula, for example, we have a three- 

 toed species ; and a similar anomaly occurs among the 

 woodpeckers. In like manner, the order Alcyones of Tem- 

 minck, which is characterized by its founder as having 



* Transactions of the Physical Class of the Asiatic Society of Ben- 

 gal, part i. p. ITS. 



