OF CARTILAGINOUS FISHES. 
CHAPTER V. 
Section I. 
Genera l Characters of the Cartilaginous Fi/hes, 
In the organs prepared by nature for the refpiration of 
'Annals, there is a great difference between thofe formed 
w Uhin the body, called lungs, and that apparatus at each 
Jl de of the head, known by the name of gills. Among all 
the terreftrial animals, and the cetaceous fillies, breathing 
ls Performed by the former of thefe contrivances, and a- 
the fp inous fifties it is carried on by the latter ; be- 
tween thefe two orders of the animal kingdom, there is 
P^ced a third, which unites them in the great fcale of 
ein g, and partakes in forne meafure of the nature of 
e ach. Thefe are the cartilaginous fifties, which, while 
they are furnifhed with apertures on each fide of the 
nec k, correfponding to the gills of the fpinous fifties, are 
fupplied with lungs within the cavity of the body, 
t*“Iagous to what we have already feen among the ter- 
^ftrial and cetaceous tribes. 
Com this double conformation in the organs of breath - 
n g> it would at firft view appear, that the cartilaginous 
ibes were a kind of privileged order of animals, pof- 
ln g a greater variety of endowments than the reft of 
L 2 the 
