INTRODUCTION 9 



a hundred years ago. The experimental method is now predominant, 

 and the niorphologist is abnost a museum specimen, yet there are 

 still some minds who see in comparative anatomy a valuable aid 

 in the investigation of function. The late Prof. J. H. Haldane said 

 that comparative anatomy may be made as valuable as experimental 

 physiology. " Future anatomy both normal and morbid will 

 certainly set itself to investigate the physiological relationships 

 which are inseparable from structural manifestations, and anatomy 

 will then be as much an experimental science as is ijhysiology." 

 Experimental biology can only be pursued in a laboratory where 

 the investigator can follow his pursuit within the law. But there 

 is a vast field for a worker in comparative anatomy in its relation- 

 ship to physiology and the investigation of function. My work 

 embodies these suggestions, and has been carried out in the scant 

 leisure allowed by a busy professional life. 1 have been encouraged 

 by the interest and support of Sir Henry Dale, the late Prof. Boycott, 

 Sir Leonard Hill and Dr. Tate Regan. I have also received much 

 help from members of the Staff of the Ministry of Agriculture and 

 Fisheries at Lowestoft, particularly I would mention Miss Thursby 

 Pelham and INIr. Michael Graham, who kindly read the manuscript 

 and made many valuable suggestions, and finally Mr. Clarke, the 

 chief laboratory assistant, without whose technical assistance 

 my work would not have been possible. My interest in the subject 

 of hearing in fish dates from my young days when I studied Otology 

 in Berlin, and worked on the literature of the cochlea at the British 

 ]\Iuseum, where I first became acquainted with the work of Bell on 

 Hearing. It is often forgotten that the resonance theory of hearing 

 first propounded by Cotugno, in 1761, was reaffirmed by Bell in 1826 ; 

 but it was not until Helmoltz, in 1863, brought his physical insight 

 t3 bear on these views that this theory was accepted, which has now 

 become exclusively associated with his name. 



