BOOK III. 



OF SPINOUS FISHES. 



CHAP. I. 



THE DIVISION OF SPINOUS FISHES. 



The third general division of fishes is into that of the spinous 

 or bony kind. These are obviously distinguished from the rest 

 by having a complete bony covering to their j^ills ; by their being 

 furnished with no other method of breathing but gills only ; by 

 their bones, which are sharp and thorny ; and their tails, which 

 are placed in a situation perpendicular to the body. This is that 

 class which alone our later naturalists are willing to admit as 

 fishes. The cetaceous class with them are but beasts that have 

 taken up their abode in the ocean ; the cartilaginous class are 

 an amphibious band, that are but half denizens of that element : 

 it is fishes of the spinous kind that really deserve the appella- 

 tion. 



This distinction the generality of mankind will hardly allow ; 

 but whatever be the justice of this preference in favour of the 

 spinous class, it is certain that the cetaceous and cartilaginous 

 classes bear no proportion to them in number. Of the spinous 

 classes are already known above four hundred species ; so that 

 the numbers of the former are trifling in comparison, and make 

 not above a fifth part of the finny creation. 



From the great variety in this class, it is obvious how difficult 

 a task it must have been to describe or remember even a part of 

 what it contains. When six hundred different sorts of animals 

 offer themselves to consideration, the mind is bewildered in the 

 multiplicity of objects that all lay some claim to its attention. 

 To obviate this confusion, systems have been devised, which 



