Sense of Sight. 97 



depends necessarily upon this condition; indeed, in fishes 

 the cornea is almost flat, while in birds of prey, which have 

 a very extended range of vision, the cornea is quite convex. 



From the lack of analogy, from the great difference in 

 construction of the ocular and auditory apparatuses of 

 fishes and terrestrial animals, and from the wide difference 

 in the properties of the media of air and water, I am con- 

 vinced that the organs of the special senses of sight and 

 hearing in fishes are not well understood at the present 

 day; and I am confident that future investigations will 

 prove them to be possessed of much greater acuteness of 

 vision and hearing, than is now accorded them. 



Most fresh-water fishes, during the breeding season, take 

 on a more pronounced coloration, the males especially be- 

 coming sometimes quite gorgeous in their nuptial dress. 

 If fishes are so defective in sight as not to distinguish 

 color, why this well-known periodical change in their 

 appearance ? 



It is a well-known fact that fishes are attracted by any 

 gay, bright, or glittering substance, as a finger-ring, a 

 sleeve-button, or a coin, and have deliberately swallowed 

 them when dropped in the water. I have caught brook 

 trout with wintergreen and partridge berries, the bright 

 scarlet color seeming to allure them, and I have even 

 caught them with a naked bright fish-hook; but all this 

 does not prove that they were the victims of a myopic 

 mistake, or that in their near-sightedness they mistook these 

 various articles for something else; neither does it prove 

 that a black bass will grab at a trolling spoon, a bluefish 

 snap at a bone squid, or a Spanish mackerel seize a metal 

 or pearl troll under the delusion that they are really choice 

 shiners, or delicate piscatorial tidbits. 



A camel, it is said, will bolt all sorts of substances, as 

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