496 



PISCES FISHES. 



(532.) Bones composing the upper jaw. The upper jaw con- 

 sists of two pairs of bones, which, from the looseness of their 

 connexion with the other bones of the face, are endowed with con- 

 siderable mobility. 



The Intermaxillary bones (17) form the greater part of the 

 margin of the jaw, and are attached by a moveable articulation to 

 the anterior extremity of the vomer. These bones are armed with 

 numerous sharp teeth. 



The Maxillary bones (18) are moveably articulated with the 

 last, and generally are in like manner furnished with teeth. In 

 some cases they are divided into two or three pieces. 



Bones of the face. The bones of the face in fishes are very 

 numerous ; but, as they are of little importance to the osteologist, 

 a bare enumeration of them will answer our present purpose, and 

 enable the student to recognize them with facility. We have 

 first the Nasal bones (20) ; then a chain of bones of variable size 

 and number (19), so disposed as to form the lower boundary of 

 the orbit, and hence named Sub-orbital bones. Behind these, 

 again, a similar chain of ossicles is not unfrequently met with, 

 arching over the temporal fossa ; and these, which are apparently 

 peculiar to fishes, are named the Supra-temporal (21). 



Ptery go-palatine and temporal system of bones. Upon each 

 side of the head is situated a somewhat complex apparatus con- 



