540 G. H. Parker 



ceeding days and with essentially similar results. On the second 

 day the wad with worms was seized i6 times daring the test hour 

 by fishes with normal olfactory organs and on the third day 54 

 times. On both these days the fishes with their olfactory tracts 

 cut made no attempts on the wad with worms nor did any fish 

 at any time nose the wormle^ wad. The movements of the two 

 sets of fishes when in the neighborhood of the wad containing 

 minced worms were characteristically different. The fishes with 

 their olfactory tracts cut swam by the wads without noticeable 

 change; those without barblets, but with their olfactory appa- 

 ratus intact almost always made several sharp turns when near the 

 wad as though seeking something, and then either moved slowly 

 away or swam more or less directly to the wad and began to nose 

 and nibble it. These reactions were so clear and so character- 

 istic that when taken in connection with the conditions of the 

 fishes, they lead inevitably to the conclusion that the olfactory 

 apparatus of the catfish is serviceable in sensing food at a distance 

 much beyond that at whicli the organs of taste are capable of 

 acting; in other words, catfishes truly scent their food. 



Whether such olfactory reactions as those that have just been 

 described are really due to smell or not is regarded by some authors 

 as an open question. Nagel ('94, p. 56), who has discussed this 

 matter at some length, concluded on rather theoretic grounds 

 that fishes could not possibly possess a sense of smell and that their 

 so-called olfactory organs act more as organs of taste than of 

 smell. Possibly the whole matter is merely one of definition. 

 With human beings smell differs from taste chiefly in the concen- 

 tration of the stimulating solution and not, as was formerly sup- 

 posed, on the state of the stimulating material, for, though we 

 usually say that we smell gaseous or vaporous materials and 

 taste liquids and solids, all these substances are in reality dis- 

 solved on the moist surfaces of wjiich ever sense organ they stim- 

 ulate. The most striking difference between taste and smell 

 with us is that we smell extreniely dilute solutions and taste only 

 very much more concentrated ones. As a result we recognize the 

 presence of many distant bodies by smell and not by taste, for 

 the very minute amount of material that reaches us from the dis- 



