aiS CARTILAGINOUS FISHES.' 



bulh, and ufing a greater variety of arts than hounds are {cen to exerff 

 in purfuing the hare. However, the porpefle not only feeks for prey 

 near the furface, but often defcends to the bottom in fearch of fand-eels 

 and fea-worms, which it roors out of the fand with its nofe, in the man- 

 ner hogs harrow up the fields for food. For this purpofe, the nofe pro-. 

 jefls a little, is (horter and (Ironger than that of the doFphioj and the 

 neck is furnifhed with very llrong mufcles, which enable it the readier to 

 turn up the fand. 



They are often taken in the Thames at London, both above the bridges 

 and below them. It is curious to obferve with what aftivity they avoid 

 their purfuers, and what little time they require to fetch breath above 

 the water. The PorpefTc yields a very large quantity of oil; and the 

 lean of fome, particularly if the animal be young, is faid to be as well 

 tailed as veal. 



Go with young ten months ; feldom bring above one at a time, and in 

 the midft of liimmer : they live to a confidcrable age (though fome fay 

 not above twenty-five or thirty years) ; and fleep with the fnout above water. 

 They feem to poflefs, in a degree proportioned to their bulk, the mao- 

 ners of whales. 



OF CARTILAGINOUS FISHES. 



THEIR firft great diftindion is, in having cartilages or griftles inflcad 

 of bones. Age, that hardens the bones of other animals, rather 

 contributes to foften theirs. The fize of all fifhes increafes with age; bur, 

 from the pliancy of the bones in this tribe, they feem to have no bounds 

 |:o their dimenfions : and it is fuppofed that they grow larger till they die. 

 Cartilaginous fifhes, like the cetaceous tribes, have organs of hearing, and 

 lungs ; like the fpinous kinds, they have gills, and a heart without a par- 

 tition; thus pofleflTing a two-fold power of breathing. This double 

 capacity of breathing, is one of the mod remarkable circumftances in the 

 hiftory of nature. The apertures by which they breathe, are placed 

 about the head ; either beneath, as in flat fifh ; on the fides, as in fliarks; 

 or on the top of the head, as in pipe-fifti. To thefe apertures are the 

 gills affixed, but without any bone to open and fiiut them, as in fpinous 

 fifhes, from which they may be eafiiy diflinguifhed by this mark. 

 ]f rom thefe are bending cylindrical duds, that run to the lungs, and arc 

 liippofed to convey the air that gives the organs their proper play. 



Fron:i this i\rudurc, they are enabled to live longer out of water than 



ihofc 



