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PRACTICAL CARP CULTURE. 



Separated by this liquid from the bone, and suspended in it is 

 the membranous ear. It consists of several parts. First and most readily 

 seen is the sack containing the otoliths or ear-bones. This lies at the base 

 and at the back of the brain, and contains a large otolith in front, behind 

 which is another very small one. This peculiar bone of which a figure in 

 given (figure c.) is loose in the sac and is of very irregular form. In a carp 

 of twelve inches long it measures about one-fourth of an inch in length. 

 To its camelled edge are attached the ends of the fine branches of the aud- 

 itory nerve which forms an intricate branching mass on the floor of the 

 chamber. These may be easily seen. 



DESCRIPTION OF FIGURES ALL ARE TWICE THE NATURAL SIZE BUT D. 



A. Hind view of head of carp. 



P. C. I'lace of posterior semi- 

 circular canal. 



E. (!. Place of exterior semi- 

 circular canal. 



S. C. Spinal chord. 



V. First vertebra. 



(). Opening at back of skull 

 leading into the brain cavity. 



15. Left ear, seen fromoutsidc. 



P. Posterior semicircular canal. 



e. Anterior semicircnbir canal, 



a. Exterior semicircular canal. 



V. Vestibule containing small ot- 

 olith. 



S. Sac containg large otolit b. 



('. otolith or earbone of right ear seen from outside. 



The notches on the edge are the points of attachment ()( I be ends of I lu.< 

 librils of the auditory nerve. 



