HISTORY OF FISHES. 



BOOK III. 



OF SPINOUS FISHES. 



CHAP. I. 



THE DIVISION OF SriNOUS FISHES. 



THK 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 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 amphi- 

 bious 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 jus- 

 tice of this preference in favour of the spinous 

 class, it is certain that the cetaceous and car- 

 tilaginous 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 ar- 

 rangement. 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 distin- 

 guished ; something that gives precision to our 

 ideas of the animal whose history we desire 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 history 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 Lin- 

 nasus have long been conspicuous : they have 

 both taken a view of the animal's form in dif 

 ferent lights; and, from the parts which most 

 struck them, have founded their respective 

 systems. 



Artedi, who was foremost, perceiving that 

 some fishes had 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 

 ventral fins seem to be the great object of his 

 system ; he considers them in fishes supplying 

 the same offices as feet in quadrupeds ; and 



