256 



1. The number of fish to which we have given names, 

 and of the figure, at least, of which we know some- 

 thing, are above four hundred. Thus to appearance 

 the history of fish is tolerably copious, but when we 

 come to examine, it will be found the greatest part of 

 these we know very little of. 



2. As most animals that live upon land have a cover- 

 ing to keep off the injuries of the weather, so all that 

 live in the water are covered with a slimy glutinous 

 matter, that, like a sheath, defends fheir bodies from 

 the surrounding fluid. Tliis substance, secreted from 

 the pores of the animal's body, serves not only to de- 

 feud but to assist the fish's easy progress through the 

 water. Beneath thi? ? in many kinds, is found a strong 

 covering of scales, that, like a coat of mail, defends 

 it still more powerfully, and under that, before we 

 come to the muscular parts of (he body, an oily 

 substance, which supplies the requisite warmth and 

 rigour. 



3. It is observable in all, that though their heads 

 Hre mrtch larger in proportion to their bodies, yet their 

 brain is considerably less than th;U of other animals-. 

 It consists of only two small ventricles placed in; the 

 fore-part of the head. 



4. Their organs of sense do not much differ from 

 those of other animals; but ia their eyes this is pecu- 

 liar, that they are quite spherical, and that the optic 

 nerves, in coming from the brain, cross each other : 

 wbcreas in other animals they incline a little to each 

 otht-r, but dj not meet. A protuberant eye would 

 have been inconvenient tor fishes, by hindering their 

 motion in so dense a medium, and their continually 

 brushing through the water would have been apt to 

 wear their eyes ; therefore their cornea is tlat : but to 

 make amends for this, and for the refraction of water, 

 different from that of air, the wise Creator has made 

 their crystalline spherical, which iu other animals is 



