OF FISH IN GENERAL. 25 



Cursory observations. 



" The two perpendiculars unite at one part in 

 one cavity, by one arm of each uniting, while 

 the other two arms or horns have no connection 

 with each other, and the arms of the horizontal ' 

 unite with the other two arms of the perpendicu- 

 lar near the entrance into the common canal or 

 cavity. 



" Near the union of those canals into the 

 common, they are swelled out into round bags, 

 becoming there much larger. 



" In the ray kind they all terminate in one 

 cavity, as has been observed; and in the cod 

 they terminate in one canal, which in these fish 

 is placed upon the additional cavity or cavities. 

 In their cavity or cavities there is a bone or 

 bones. In some there are two bones: as the jack 

 has two cavities, we find in one of those cavities 

 two bones, and in the other only one; in the ray 

 there is only a chalky substance. At this union 

 of the two perpendiculars in some fish enters the 

 external communication, or what may be called 

 the external means. This is the case with all 

 the ray kind, the external orifice of which is 

 small, and placed on the upper flat surface of the 

 head ; but it is not every genus or species of fish 

 that has the external opening. 



" The nerves of the ear pass outwards from 

 the brain, and appear to terminate at once on 

 the external surface of the swelling of the semi- 

 circular tubes above described. They do not 

 appear to pass through those tubes so as to get 



VOL. v. NO. 31. D 



