CHAPTER VIII. 



THE VERTEBRAL COLUMN OF FISHES. 



From these creatures — partly reptiles, partly 

 fishes — we come to the class of vertebrate 

 animals to which the term fishes is with 

 propriety restricted. We have already given a 

 general sketch of the leading characteristics of 

 this class, and, in tracing the modifications of 

 the anterior extremities, we were led to a 

 consideration of the pectoral, and also the 

 ventral fins of these aquatic creatures ; and, 

 although we abstained from minutiae, we ven- 

 tured to show some of the most remarkable 

 modifications to which these analogues of the 

 limbs of the higher animals are subject. We 

 described the pectoral and ventral fins as 

 combining with the tail to fit these scaly 

 tenants of the waters for easy motion in their 

 native element ; and we have now to show 

 how the spine harmonizes with the structure 



