Reighard. — Senses and Learning in Fishes 137 



many qualities of smell is probable from the facts now 

 to be set forth. 



1. Taste in fishes. In man, the organs of taste are 

 situated chiefly on the tongue. In fishes they occur in 

 the tongue, in the lining membrane of the mouth and for 

 a considerable distance back in the throat. But fishes 

 differ from higher back-boned animals in that the or- 

 gans of taste, or taste buds, occur not only in the mouth 

 but over the outer surface. In the catfishes they are 

 found over the whole outer surface, especially on the 

 barbels. In the codfishes they occur on the body and 

 fins, but are concentrated on the slender pelvic fins, 

 which may be stretched down and forward under the 

 throat. In other fishes they have various situations on 

 the outer body surface (Herrick, 1903). 



If a piece of cotton wool, soaked in meat juices, is 

 touched to the side of the tail of a bullhead while his 

 eyes are covered, the animal at once turns and seizes the 

 cotton (Herrick, 1903). He cannot see it but he feels 

 and tastes it. If the cotton wool is used without the meat 

 juices the fish at first seizes this also, but he soon learns 

 to distinguish between the feel of the cotton alone and 

 the feel and taste of the cotton soaked in meat juice. 

 Threafter he pays no attention to the cotton unless soaked 

 in the meat juices. If meat juices are squirted against 

 his side he turns and bites at the nozzle of the syringe. 

 If water alone is used he does not turn, but may move 

 away as though irritated. He pays no attention to pieces 

 of brick touched to the side unless these are soaked in 

 meat juice. The fish then may feel and taste those sapid 

 substances that touch the skin and may attend to them. 

 He feels non-sapid substances, but pays little attention 

 to them so long as they touch him but gently. 



It is then clear that a fish may taste substances in con- 

 tact with the skin as well as those in the mouth. Parker 

 (1912), has found that when salt, sour and alkaline 

 liquids of certain concentrations are squirted gently 

 against the mid-trunk or tail of a bullhead (Ameiurus 

 nebidosus) , the animal does not turn as though to seize 



