THE EAR OF MAN. 223 



common Dog-fish of the Bay of Naples. Steiner's ex- 

 periments proved that so long as the fibres of the 

 acoustic nerve were neither pulled so as to disturb 

 their central relations, nor displaced in a manner in- 

 jurious to their peripheral terminations, disturbances 

 in the equilibrium of the body did not make their 

 appearance. While observing these conditions it was 

 possible for him to cut out one, several, or all six of 

 the semicircular canals witJioiU destroying or in the 

 least disturbing the fisJi s power to equilibrate its body^ 

 though the operation evidently caused the fish very 

 painful sensations, i.e. very intense irritation of cen- 

 tral end cells. 



Now under the old hypothesis of the equilibration 

 functions of the semicircular canals, these removals 

 without equilibrative disturbances would be impossible. 

 Experiments of a similar nature performed on warm- 

 blooded animals were formerly used as evidence in proof 

 of the theory. In all of these experiments disturbances 

 of the power of equilibration never failed to make their 

 appearance. These disturbances, however, were due to 

 the conditions under which the experiments on warm- 

 blooded animals are necessarily performed, and are not 

 directly related to the injury to the nerve from simple 

 cuttino:. In Pisfeons whose semicircular canals have 

 been more or less injured ^ or destroyed, the loss of 

 coordinating power is certainly to be connected with 

 the injury done to the richly nervous structures ; but it 

 does not follow that this loss of coordination is due 

 solely to the disturbance of the function of the canals, 



1 As in the experiments by Elourens, Cyon, and others. 



