646 



A HISTORY OF 



OF SPXNOUS FISHES. 



CHAPTER CXLVII1. 



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 hav- 

 ing a complete bony covering to their gills ; 

 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 appellation. 



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 cartilagi- 

 nous 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 com- 

 parison, 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, throwing several fishes that 

 agree in many particulars into one group, and 

 thus uniting all into so many particular bodies, 

 the mind that was incapable of separately con- 



sidering each, is enabled to comprehend all, 

 when thus offered in larger masses to its con- 

 sideration. 



Indeed, of all the beings in animated na- 

 ture, fishes most demand a systematical 

 arrangement. Quadrupeds are but few, and 

 can be all known ; birds, from their seldom 

 varying in their size, can be very tolerably 

 distinguished without system ; but among 

 fishes, which no size can discriminate, where 

 the animal ten inches, and the animal ten feet 

 long, is entirely the same, there must be some 

 other criterion by which they are to be dis- 

 tinguished ; something that gives precision to 

 our ideas of the animal whose history we de- 

 sire to know. , 



Of the real history of fishes, very little is yet 

 known ; but of very many we have full and 

 sufficient accounts, as to their external form. 

 It would be unpardonable, therefore, in a his- 

 tory of these animals, not to give the little we 

 do know ; and, at least, arrange our forces, 

 though we cannot tell their destination. In 

 this art of arrangement. Artedi and Linnaeus 

 have long been conspicuous : they have both 

 taken a view of the animal's form in different 

 lights; and, from the parts which most struck 

 them, have founded their respective systems. 



Artedi, who was foremost, perceiving that 

 some fishes had hard prickly fins, as the pike; 

 that others had soft pliant ones, as the herring; 

 and that others still wanted that particular fin 

 by which the gills are opened and shut, as the 

 eel, made out a system from these varieties. 

 Linnaeus, on the other hand, rejecting this 

 system, which he found liable to too many ex- 

 ceptions, considered the fins, not with regard 

 to their substance, but their position. The 



