OF CARTILAGINOUS FlSHESi 



CHAPTER V. 



Section L 



Generat CharaSiers of the Cartilaginous Fijhe:* 



In the organs prepared by nature for the refplratlon o£ 

 animals, there is a great difference between thofe formed 

 within the body, called lungs, and that apparatus at each 

 fide of the head, kno\Vn by the name of gills. Among all 

 the terreftrial animals, and the cetaceous fifties, breathing 

 is performed by the former of thefe contrivances, and a- 

 niong the fpinous fiflies it is carried on by the latter ; be- 

 tween thefe two orders of the animal kingdom, there is 

 placed a third, which unites them in the great fcale of 

 being, and partakes in fome meafure of the nature of 

 each. Thefe are the cartilaginous fiihes, which, while 

 they are furniihed with apertures on each fide of the 

 neck, correfponding to the gills of the fpinous fiihes, are 

 alfo fupplied with lungs within the cavity of the body, 

 analagous to what we have already feea among the ter- 

 reftrial and cetaceous tribes. 



From this double conformation in the organs of breath- 

 ing, it would at firft viev^; appear, that the cartilaginous 

 tribes were a kind of privileged order of animals, pof- 

 fefling a greater variety of endowments than the reft of 



L a the 



