36 C. WINKLER. THE CENTRAL COURSE 



side. If now these innervations are destroyed likewise on the oppo- 

 site side, as is the case after the second operation, there is no 

 longer any reason for the prevailing of tonic spasms on that side. 

 The normal position is regained. But all movements are feebler, 

 more unsteady, because they are supported by a reduced inner- 

 vation. Head, neck and eyes seem therefore to be recovered, the 

 extremities are atonic. The atony of the extremities exists on both 

 sides, it is strongest in the upper extremities, but is very marked 

 also in the lower ones. 



5. The results of destruction of the cochlea. 



After the removal of the cochlea on one side , the animal , when 

 loosened from the operation-table, shows usually in both eyes some 

 nystagmus, by means of which is indicated the same deviation of 

 the eyes that is so conspicuous after destruction of the labyrinth, 

 and in the same direction. The head is also poised more or less 

 obliquely. The homo-lateral ear is often hanging downward and the 

 atony of the extremities on the operated side is plain. 



A short time after the operation these phenomena have much 

 diminished. Still the experienced observer may easily distinguish 

 the operated side, because a somewhat oblique position of the head 

 is permanent, as is likewise a propensity to nystagmus or else to 

 a deviation of the eyes , and also is the atony of the extremities on 

 that side. 



But all these phenomena are shown in a far lesser degree than 

 after destruction of the labyrinth. It occurs rather often, that one 

 or two weeks after the operation the animal begins to roll, whilst 

 the involuntarily assumed position of the eyes, the turning of head 

 and neck, and the atony of the lower extremities increase. This 

 proves , that the discharge of endolymph that will nearly always 

 complicate the removal of the cochlea - - has brought a compli- 

 cation by altering the contents of the vestibulum. In this manner 

 the same complex of phenomena is brought about that appears after 

 one-sided removal of the labyrinth. 



The removal of both cochleae has the following effects : 



1. The animal does no longer react on the sound-impressions. 



2. It walks with wide-stretched legs, head and ears are hanging 

 down, the back is sunken in. The head, though unsteady , is less 

 unsteady than after removal of the labyrinth. The eyes are stan- 

 ding straight, but nystagmus is easily provoked by moving the 

 head. Briefly, both after one-sided and after double-sided extir- 



