480 WILD ANIMALS. 



provided with gills that would enable them to breathe while com- 

 pletely submerged. The hippopotamus possesses the' capability of 

 remaining under the water a considerable time when compared 

 with the powers possessed by other large quadrupeds, yet the 

 intervals between the respirations of these huge beasts are short 

 by comparison with the necessities of the various members of 

 the seal family. 



As was shown in a previous chapter, the hippopotamus appears 

 created more to live on the water than in it, for although the mas- 

 sive body is kept submerged, yet the senses all being situated upon 

 the flat, broad, upper plane of the head, this part of the animal, 

 when it is in a quiescent state, is generally kept on or above the 

 surface. They are also supplied with four legs, formed on the 

 ordinary model in all but their size, and they are used for walking 

 on the land in the same manner as other quadrupeds, as well as 

 for swimming in the water. The seals, however, display com- 

 pletely different forms, for they exhibit modifications adapting 

 them to a thoroughly aquatic existence. When these divergencies 

 from other animal types are carefully examined, the marvellous 

 resources of the creative Power are again exhibited, and make the 

 study of these denizens of the seas wonderfully interesting. 



The common or earless seals, although difiering most materially, 

 yet in outward appearance, bear a closer resemblance to the fish 

 family than to that of ordinary quadrupeds, for the body is elon- 

 gated and tapers from the chest to the extremity. But it is in the 

 formation and situation of the limbs that the variations from the 

 ordinary type of mammals are, perhaps, most conspicuous. The 

 limbs are short and so completely enveloped in the skin of the 

 body that little more than the paws project. All the feet are five-toed 

 and completely webbed; the hind-feet are directed backwards, so as 

 to appear like a prolongation of the body, with the tail, which is a 

 short one, between them. The webbed intervals between the toes 

 are capable of considerable expansion, particularly those of the hind- 

 feet, and they have great propulsive power, for by opening and shut- 

 ting them the animal can make them act like the blades of a steamer's 

 screw-propeller, only with far greater variety of motion. The spine 

 is very flexible, and admits of considerably more curvature than 



