FIN APPENDAGES. 



37 



this cut, and which is a species of Lake Trout from the 

 continent of Europe, that it has eight fins in all, including the 

 tail, six of which are displayed in the lateral view, two being on 



^ -^ --'-'::^^f^./( (^ 



J I 



T,... ^ '- " 



~-> E 

 3 



n 



the farther side ; and seven in the view of the back taken from 

 above ; the eighth, which is indicated by a dotted line, being 

 on the under part of the fish. 



Of these appendages, by which the motion, position in the 

 water, and direction of the animal, are regulated; the two 

 nearest the head, one on either side, a a, are the pectorals ; the 

 two somewhat farther back, one on either side, b b, are the 

 ventrals ; the one on the under side, yet farther back, c, the 

 anal ; the tail, d, the caudal ; and the two on the ridge of the 

 back, E E, the dorsal ; f is the lateral line. 



These are all the denominations of fins possessed by any 

 fish, although the number and size, as well as the structure, 

 vary in the various species, which are thus easily distin- 

 guished. 



Of these fins, all the classes of fish concerning which this 



