54 ANIMAL LIFE 



of its time in the sea near the coast, and only going 

 ashore to rest and to bring up its family. The body 

 is thick in front and flattened behind. The tail has 

 almost disappeared, and on either side of it the hind 

 limbs are held rigidly out at full length. Between 

 the fingers and toes the skin has grown so as to convert 

 the fore-limbs into paddles and the hind-limbs into a 

 propeller. On land a seal shuffles awkwardly on its 

 belly, only using its hands if pressed ; but at sea the 

 flattened hind-limbs, together with the lateral muscles 



FIG. 9. -The White Seal (Lobodon) of Antarctic shores. (From a 

 specimen in the Manchester Museum x ^g. ) 



of the body, enable it both to swim with great ease 

 and to ascend periodically to the surface for air. The 

 forepaws are used for steering. 



The porpoises and dolphins, the baleen and toothed 

 whales, are as perfect in the art of swimming as any 

 fish. Their bodies, denuded of hair, are usually of a 

 build so completely adapted for cleaving the water 

 that boat-builders could design the lines of their craft 

 from models of whales. The head is a cone pointed in 



