304 



THE SENSORIAL FUNCTIONS. 



more especially the membranous labyrinth, floating in the 

 perilymph (p.) The form of this latter part is still more 

 distinctly seen, in Fig. 396, where it is represented in a po- 

 sition exactly corresponding to the former figure, but whol- 

 ly detached from the bony labyrinth, and connected only 

 with the nervous filaments which are proceeding to be dis- 

 tributed to its different parts. 



398 



A simple inspection of these figures, in both of which the 

 corresponding parts are marked by the same letters, will 

 show at once the form and the connexions of the three semi- 

 circular canals, (x, Y, z,) each of which present, at their ori- 

 gin from the vestibule, a considerable dilatation, termed an 

 ampulla (A, A, A,) while, at their other extremities, where 

 they terminate in the vestibule, there is no enlargement of 

 their diameter: and it will also be seen that two of these ca- 

 nals (x and Y) unite into one before their termination. The 



