THE SENSE OF HEARING IN FISHES. 75 



in vibration normal fishes and fishes in which the skin was insensi- 

 tive responded quite regularly with fin movements whereas those 

 in which the ears had been eliminated showed no reactions. Hence 

 there seemed to be no doubt that the ear of Fundulus was stimu- 

 lated by tones. 



In view of the discrepancy between the results of Kreidl and 

 those of Parker, Bigelow (1904) was led to retest the goldfish. 

 Three sets of fishes were prepared corresponding to those that had 

 been used in Fundulus by Parker. These sets were subjected to 

 the tones from an electrically driven tuning-fork led into the water 

 in which the fish was by bringing the base of the fork into con- 

 tact with the wooden side of the aquarium. Normal fishes re- 

 sponded in 78 per cent, of the trials. Fishes with insensitive skins 

 but normal ears reacted in 80 per cent, of the trials. While fishes 

 in which the eighth nerves had been cut gave no responses what- 

 soever to the tone of the fork. These results agreed in the main 

 with what had been obtained by Parker in Fundulus, but disagreed 

 with Kreidl's results on the goldfish. Bigelow, therefore, sought 

 for the grounds of this disagreement. For this purpose he re- 

 peated exactly Kreidl's procedure in preparing the fishes and in- 

 stead of eliminating the ear by cutting the eighth nerve, he re- 

 moved this organ by opening the skull and withdrawing the semi- 

 circular canals and the attached parts of the ear as Kreidl had done. 

 On testing such goldfishes, they were found, as Kreidl had asserted, 

 to respond to tones as normal fishes do, but on dissecting them, it 

 was discovered that by this method only the utriculus had been taken 

 out with the semicircular canals and that the sacculus, uninjured 

 and intact, had been left behind. It was, therefore, clear that 

 Kreidl's operation removed only part of the ear and that the portion 

 left behind was the very part most likely to be concerned with hear- 

 ing. Thus the discrepancy between Kreidl's work and that of 

 Parker and of Bigelow was cleared away. 



Following these results came a series of papers that were in part 

 favorable to the opinion that fishes could hear and in part opposed 

 to this view. Of those in opposition the first was by Korner (1905). 

 This author tested twenty-five kinds of fishes that had become 



