206 MAMMALIA. 



especially tliose wliicli are indented witli caverns, 

 to wliicli tliese animals delight to resort, and in 

 wliicli tliey congregate. They may often be seen 

 off the shore, in summer weather, playing in the 

 sea. The various species of Whales and Dolphins 

 are dwellers in the broad ocean, usually associating 

 in herds, and approaching the shore only by 

 accident ; the smaller kinds frequently ascend our 

 tidal rivers, and the Whales are not rarely seen to 

 enter bays and harbours, especially on the northern 

 and western shores, where they are sometimes 

 stranded. 



Identification. — The presence of hind limbs ; 

 their structure ; the comparative size of the head ; 

 its prolongation into a snout ; the presence of a 

 dorsal ; the number and arrangement of the teeth, 

 — are the points which principally require notice 

 in the determination of the species. 



Authorities. — Professor Bell's " History of 

 British Quadrupeds," M. Fred. Cuvier's " Historie 

 Naturelle des Cetacees," and the volumes on Seals 

 and Whales in Jardine's " Naturalist's Library," 

 have afforded me materials for the following 

 enumeration. 



MA]\[MALIA. 



Vertebrate animals having warm blood ; breath- 

 ing by means of lungs ; bringing forth living young, 

 which are suckled and nourished with milk. 



Order CETACEA. 



Form fish-like ; skin naked ; fore limbs short ; 

 bones of the hand concealed in a skinny fin with- 



