From the Woods Hole Laboratory of the United States Bureau of Fisheries.'
I. INTRODUCTIOX
Fishermen and others interested in the question of bait or the feeding habits of fishes, have long held and expressed the opinion that many species obtain their food partly or entirely through the use of the sense of smell. Such have observed that, while the more agile among the teleostean fishes clearly avail themselves of their eyes in the pursuit of food, many species, both among the Telc osts and Selaehians become acquainted with the proximity of food in R different manner. Some feed only in the dark, while others possess eyes, so small and imperfect as to be of little assistance. In still other cases the method of search indicates the use of another sense, as for instance the carp, ploughing through the mud and grass; the catfish, with its barbels trailing over the bottom, or the skates and dogfish which carefully search the sea floor with the ventral surface of their snouts in close proximity to it. Fishermen say that these species secure their food by the use of "smell," or possibly "taste," in the case of carp and catfish. Writers on the subject make similar statements (see Bateson, '90). When these are carefully analyzed, however, it will always be noted that the term "smell" means, in the minds of such observers, the recognition of food by ineans of a chemical sense. This socalled sense of smell may, then, consist of smell, taste, or a more general chemical sense.
Herrick ('02) shows that many species of Teleosts, such as the Cyprinoids and Siluroids, which are well supplied with taste