84 



SUBKINGDOM VERTEBBATA. 



of the head ; fore-limbs, which, like the human arm, consist 

 of a shoulder-blade, humerus, radius, ulna, and five fingers; 

 a tail, horizontally flattened and fluked; and no hind limbs. 

 They are subdivided into Eamilies, according to the presence 

 or absence of teeth : 



CETACEA 



TEETH IN BOTH JAWS. 

 " LOWER JAW. 



" WANTING. 



Delphinidae, 

 Physeteridae, 

 Balaeuidae, 



Dolphin. 

 Sperm Whale. 

 Riyht Whale. 



Fig. 133. 



Delphinidse. The Common Porpoise frequents the 

 mouths of rivers, often venturing some distance up stream in 



pursuit of herring and 

 other migratory fish. * 



The Delphinus delpliis 

 is the Dolphin f of Grecian 

 mythology. 



The Beluga of the north- 

 ern Atlantic coast is re- 

 markable when mature for 

 the clear white hue of its 

 skin, though when young it is black. 



The Narwhal, or unicorn, has one of its upper canines 

 developed into a straight, spirally-twisted pole of ivory, seven 

 to ten feet long.J 



185. 



Phoccena communis, Common Porpoise. 



Beluga canadensis, White Whale. 



* It frequently comes to the surface of the water to breathe, where it tumbles and 

 frisks about, presenting an appearance which has given it the name of the 

 Puffing Pig. 



t This is common to all seas, but should not be confounded with the Dolphin of 

 sailors, which in dying displays all the colors of the rainbow the latter being the 

 coryphSne, a true scaly fish. 



$ This formidable weapon has been forced through the sides of a whale ship. It 

 can be used only as a means of defence or of ploughing up the mud for food, as the 

 animal feeds mainly upon soft shell-fish. 



