SENSE OF SMELL IN FISH. 67 



that a short time afterwards, shoals of them came, pro- 

 bably from a considerable distance, on the current con- 

 veying the taint to them. They could not possibly 

 obtain this information through the medium of sight, 

 as the night was too dark for even our boat to be visible 

 only three feet above them ; and they had apparently 

 collected from a considerable distance below. Neither 

 could it well be the sense of taste that was their guide 

 in this case, for the gustatory nerves in fish are very 

 meagerly developed indeed, as the physical conformation 

 of all the organs of the mouth would lead us to suppose. 

 The tongue, for instance, the chief seat of the sense of 

 taste in the higher animals, is in fish composed principally 

 of bone, and dense insensible cartilage, on which no 

 nervous papillae ramify. In corroboration of my opinion, 

 it will be found that if blood be poured into a river, it will 

 very shortly put every eel within half a mile below in 

 motion, and apparently eager in search of the food ; 

 while, if little be poured in from time to time, they will 

 be seen following up the scent like a pack of hounds. Or 

 again, if the entrails of a fowl, or any other garbage, is 

 enclosed in either the centre of a bottle of straw, or even 

 in a wooden box with a hole in it, they will be certain 

 to find it out in a very short time ; and such may be 

 converted into efficient eel-traps. What sense then but 

 that of smell, enables these fish to discover the presence 

 of substances placed in positions where they cannot 

 possibly be seen ? 



In pike-fishing also (and I have caught some scores), 

 I have invariably found that a bait that had been kept 



