628 



A HISTORY OF 



after they are brought on shore. From hence 

 this tribe seems possessed of powers that other 

 fishes are wholly deprived of; they can re- 

 main continually under water, without ever 

 taking breath ; while they can venture their 

 heads above the deep, and continue for hours 

 out of their native element. 



We observed, in a former chapter, that 

 spin ous fishes have not, or at least appear not 

 to have, externally any instruments of genera- 

 tion. It is very different with those of the 

 cartilaginous kind, for the male always has 

 these instruments double. The fish of this 

 tribe are not unfrequently seen to copulate ; 

 and their manner is belly to belly, such as may 

 naturally be expected from animals whose 

 parts of generation are placed forward. They 

 in general choose colder seasons and situations 

 than other fish for propagating their kind ; 

 and many of them bring forth in the midst of 

 winter. 



The same duplicity of character which 

 marks their general conformation, obtains 

 also with regard to their manner of bringi-;g 

 forth. Some bring forth their young alive ; 

 and some bring forth eggs, which are after- 

 wards brought to maturity. In all, however, 

 the manner of gestation is nearly the same ; 

 for upon dissection, it is ever found, that the 

 young, while in the body, continue in the egg 

 till a very little time before they are excluded : 

 these eggs they may properly be said to hatch 

 within their body ; and as soon as their young 

 quit the shell, they begin to quit the womb 

 also. Unlike to quadrupeds, or the cetaceous 

 tribes, that quit the egg state in a few days 

 after their first conception, and continue in the 

 womb several months after, these continue in 

 the body of the female, in their egg state, for 

 weeks together ; and the eggs are found linked 

 together by a membrane, from which, when 

 the foetus gets fir e, it continues but a very short 

 time till it delivers itself from its confinement 

 in the womb. The eggs themselves consist 

 of a white and a yolk, and have a substance, 

 instead of shell, that apt ly may be compared 

 to softened horn. These, as I observed, are 

 sometimes hatched in the womb, as in the 

 shark and ray kinds; and they are sometimes 

 excluded, as in the sturgeon, before the ani- 

 mal comes to its time of disengaging. Thus 

 we see that there seems very little difference 

 between the viviparous and the oviparous 

 .kinds, in this class of fishes : the one hatch 



their eggs in the womb, and the young con- 

 tinue no long time there ; the others exclude 

 their eggs before hatching, and leave it to 

 time and accident to bring their young to 

 maturity. 



Such are the peculiar marks of the carti- 

 laginous class of fishes, of which there are 

 many kinds. To give a distinct description 

 of every fish is as little my intention, as per- 

 haps it is the wish of the reader ; but the pecu- 

 liarities of each kind deserve notice, and the 

 most striking of these it would be unpardon- 

 able to omit. 



Cartilaginous fish may be divided first into 

 those of the shark kind, w ith a body growing 

 less towards the tail, H rough skin, with the 

 mouth placed far beneath the end of the nose, 

 five apertures on the sides of the neck for 

 breathing, and the upper part of the tail longer 

 than (he lower. This class chiefly compre- 

 hends the Great White Shark, ti>e Balance 

 Fish, the Hound Fish, the Monk Fish, the 

 Dog Fish, the Basking Shark, the Zygaena, 

 the Tope, the Cat Fish, the Blue Shark, the 

 Sea Fox, the Smooth Hound Fish, and the 

 Porbeagle. These are all of the same nature, 

 and differ more in size, than in figure or con- 

 formation. 



The next division is that of flat fish ; and 

 these their broad, flat, thin shape, is sufficient- 

 ly capable of distinguishing from all others of 

 this kind. They may be easily distinguished 

 also from spinous flat fish, by the holes through 

 which they breath, which are uncovered by a 

 bone; and which, in this kind, are five on 

 each side. In this tribe we may place the Tor- 

 pedo, the Skate, the Sharp-nosed Ray, the 

 Rough Ray, the Thornback, and the Fire 

 Flare. 



The third division is that of the slender 

 snake-shaped kind ; such as the Lamprey, the 

 Pride, and the Pipe fish. 



The fourth division is of the Sturgeon and 

 its variety, the Ising-glass Fish. 



The last division may comprise fish of dif- 

 ferent figures and natures, that do not rank 

 under the former divisions. These are the 

 Sun Fish, the Tetrodon, the Lump Fish, the 

 Sea Snail, the Chiinaera, and the Fishing 

 Frog. Each of these has somewhat peculiar 

 in its powers or its forms, that deserves to be 

 remarked. The description of the figures 

 of these at least may compensate for our 

 general ignorance of the rest of their history. 



