INTELLIGENCE AND SPECIAL SENSES. 181 



threads, etc., and kittens will seize, claw and bite almost 

 any moving small object; but these vagaries are attributed 

 to the idiosyncracies of the animals mentioned, while in 

 fishes they are ascribed to defective sight. 



But what are a fish's eyes for? According to our 

 present knowledge they are to enable him to become " a 

 snapper-up of unconsidered trifles" with hooks attached 

 to them ! 



Now, so far as the artificial fly is concerned, when it is 

 cast lightly upon a fretted surface, I think it is generally 

 taken by a fish under the impression that it is a natural 

 insect ; but with regard to trolls of all kinds, as spoons, 

 squids, spinners, propellers, etc., and very often with re- 

 gard to the artificial fly, I am of the opinion that they are 

 taken through a spirit of mere bravado, curiosity or wan- 

 tonness, and not with the idea that they are living objects 

 of prey. They are seized by the fish because they are 

 bright, attractive and in motion ; not because they are 

 hungry, but because they are in a biting mood, for we 

 often find, nay, most always find, that fish so taken are 

 already gorged with food. 



SENSE OF HEARING. 



There is no external ear in fishes, the internal ear alone 

 existing, and which is extremely delicate in its construc- 

 tion. 



Dr. John Hunter observed that it varied much in the 

 different genera of fishes, but that in all it consisted of three 

 curved tubes, which united one with another. The whole 

 organ is composed of a kind of cartilaginous substance, 



