INTRODUCTION. 37 



emerge from the gravel and the egg, where they 

 had lain long neglected by the individuals who 

 there deposited and deserted them ; but the whales 

 are brought ahve into the world, and the cub is 

 nourished for months by its mother's milk, and 

 disports itself around her in playful affection, 

 like the faA^^l or the lamb in the sunny glade. 

 Fish are cold-blooded — their circulating fluid being 

 only exposed to the water, in the gills ; but the 

 whale has no gills, nor any thing resembling them ; 

 on the contrary, it has true lungs, in a great bony 

 chest, into which the air is freely admitted — ^not 

 indeed by the mouth, but by a peculiar apparatus 

 to be afterwards explained, and through which the 

 animal breathes the pure air of heaven like other 

 mammalia, and is thus enabled to maintain the warm 

 temperature of its body even in the midst of the 

 icy seas. Fish never breathe ; and if removed 

 from the water, and brought into the air, imme- 

 diately die ; whereas the Cetacea, if deprived of air 

 and confined under water, are speedily and literally 

 drowned. 



The Cetae, therefore, are not fishes, but true 

 mammalia. Not only in their internal organization, 

 but, to a great extent, in their osseous structure, 

 they approximate to the quadrupeds or the mam- 

 malia of the land ; and it is not a little interesting 

 to trace the wondei-ful adaptations by which an 

 animal of such a structure and habit of body is 

 fitted to become the inhabitant of a different element. 

 Before we proceed, accordingly, to introduce the va- 



