52 Bulletin of Laboratories of Denison University. [Voi. xii 



rockling) the fish be blind or not The percep- 

 tions, then, by which these animals recognize the presence of 

 food are clearly obtained by means of the olfactory organs, and 

 apparently exclusively through them. I was particularly sur- 

 prised to find no indication of the possession of such a function 

 by the sense organs of the barbels and lips, or by those of the 

 lateral line. As has been already described, the pelvic fins and 

 barbels of the rocklings [Motella) and the lips, &c., of most 

 fishes bear great numbers of sense organs closely comparable 

 in structure with the taste buds of other vertebrates. No one 

 who has seen the mode of feeding of the rockling or pouting 

 {Gadus liiscus) can doubt that these organs are employed for 

 the discrimination of food substances; but the fact already men- 

 tioned, that the rockling in which the olfactory organs had been 

 extirpated did not take any notice of food that was not put close 

 to it, points to the conclusion that they are of service only in 

 actual contact with the food itself" Bateson gives also a con- 

 siderable list of fishes which he has observed to get their food^ 

 chiefly by the sense of sight, and he is doubtless correct in as- 

 serting that the majority of fishes belong to this class. None of 

 these sight-hunting fishes while living in his tanks appeared able 

 to see their food by night, or even in twilight. None of the 

 fishes which he enumerates as belonging to this class showed 

 symptoms of interest when the juice of food substances was put 

 into the water, and other evidence is brought forward to show 

 that the sense of smell plays little or no part in helping them to 

 discover their food. 



I have not studied any of the species mentioned by Bate- 

 son, but for the forms studied by me which have an extensive 

 supply of terminal buds on the outer skin I fully confirm most 

 of the statements quoted above save that in determining the 

 part played by sight I did not blind any of my fishes and save 

 that the statement that in fishes of his first group "at no time 

 was there there the slightest indication of any recognition of any 

 food substance by sight" is strictly true of none of my fishes 

 except Ameiurus, though in some of the other cases it is ap- 

 proximately true. 



