268 AYERS. [Vol. VI. 



an das Cylinderepithel anschlagen, so vverden sie unstreitig 

 durch den Stoss erschiittert. Die Erschutterung pflanzt sich 

 weiter fort von den Cylinderzellen auf die Grundmembran und 

 von dieser auf den Nerv, der mit seiner Spitze unmittelbar an 

 dieselbe sich anlegt." In this way, says the author, the trans- 

 mission of a tone to the nerve would occur in a very simple 

 manner without the necessity of recourse on the part of nature 

 to a more complicated structure. 



In 1876, Lavdowsky (178) published his physiological conclu- 

 sions, which were based not on actual physiological experiments, 

 since, says he, microphysiological experiments on the cochlea 

 of warm-blooded animals are almost impossible, but on a care- 

 ful analysis of the structure and composition of the organs in 

 question ; while the only experimental basis to serve as guid- 

 ing light was the well-known experiments of Hensen's on the 

 Decapod ear, and Ranke's on the otocysts of Pterotrachea, with 

 the demands which the physiological acoustics make on the 

 auditory organs of tone perception. The demands of acoustics, 

 according to Lavdowsky, may be stated under three heads. In 

 order to account for audition there must exist in the auditory 

 organ, as our author conceives it, three mechanisms. They are 



I St. A vibration mechanism, capable of responding to and 

 very sensitive to vibrations of the surrounding medium. 



2d. A percipient mechanism. 



3d. A regulation mechanism or damping apparatus. 



Since, however, it is impossible to separate the cochlea from 

 the rest of the canal complex when considering the physiology of 

 audition, it necessarily follows that one must use hypotheses to 

 satisfy the demands of acoustics. 



This investigator considers that the cochlea performs one 

 function, the rest of the ear the other of the two functions as- 

 sumed to belong to this organ ; and the former, he says, is the 

 most important one belonging to the ear. 



The whole of the ear, save the cochlea, subserves the func- 

 tion of simple auditory perceptions, while the cochlea subserves 

 the double function of a tone differentiator or analyzer, as well 

 as that of sound perception. The utriculo-sacculus and semicir- 

 cular canals perceive the qualitative differences existing between 

 various forms of motion, e.g. light and sound waves, but cannot 

 perceive, except in the most general way, the character of a 

 mass of tones or a musical picture. 



