THE AMPHIBIOUS CARN1VORA. 65 



gment on his five senses ; and were then to infer 

 that he was imperfectly constituted, because, in 

 his hapless plight, he saw indifferently, heard and 

 smelt worse, and so on ; should we approve their 

 inference, or admire their wisdom? The truth is, 

 the eye of the Amphibia is a perfect study, and 

 would well repay a lengthened description. It 

 is very large, and quite spherical ; the sclerotic or 

 outer membrane is very peculiar, inasmuch as it has 

 a soft and thin zone round its middle, thickly 

 covered with muscles, whilst both before and behind 

 it is thick and almost cartilaginous.* The precise 

 use of this structure has not yet been discovered, 

 though Blumenbach has thrown out the idea that 

 it may enable the Seal to see both in air and water 

 Rosenthal so far confirms this opinion by having 

 observed, that the mechanism is peculiar to those 

 animals which live in a dense medium, such as 

 water ; that the remarkable thickness of the coat is 

 found in those animals in which the orbit is not 

 wholly osseous, and that some fishes have the 

 sclerotic nearly cartilaginous. With regard to the 

 ear, it ought not to be forgotten that fishes, with no 

 external ear or aperture, have in their native ele- 

 ment an acuteness of hearing which, according 

 to some respectable authorities, far exceeds our 

 own ; and Rosenthal states that the auditory nerve 

 of the Seal is very large. Respecting the sense of 

 touchy we shall here quote M. F. Cuvier, who 



See its Dissection in the Crested Seal, by Drs King and 

 Ludlow, in our account of that animal. 



VOU VIII. B 



