CHAPTER VII 



Order IV. Carnivora (continued) 



Sub-Order 2. CARNIVORA OF THE SEA 



PASSING from the Carnivora of the land to those of the 

 sea, we come to the Pinnipedia (Lat., pinna, a fin ; 

 pes, pedis, a foot), the fin-footed animals, or Seals, which 

 include the Sea Lions and the Walrus. Various other 

 marine carnivores (Cetacea) form an order of their own. 



Before describing the life-history of any particular 

 member of the sub-order, it will be well to examine the 

 skeleton of the Seal, and note how, by certain modifications 

 of the bones, the mammal practically becomes a fish, just as 

 in the Bats it is in reality transformed into a bird. 



The name Pinnipedia is very appropriate, as is the 

 alternative name Pinnigrada (Lat., pinna, a fin ; gradus, 

 a step). The limbs are shortened, and are so arranged that 

 they act exactly like the pectoral fins and tail of a fish. 

 The hind limbs, especially, are directed backwards, and 

 the bones are so modified that, when the feet are pressed 

 together, they can be swept from side to side as if they were 

 the tail fin of a fish. Indeed, as the Seal feeds on fish, as 

 does the otter, it is necessary that it should be swifter than 

 its prey. In the otter the tail is the propelling organ ; but 

 in the Seal the hind limbs are used in tail fashion. 



In the water the movements of the Seal are extremely 

 graceful and rapid, but on land its motions are exceedingly 

 awkward. The limbs, even the fore ones, are practically of 

 no service. The spine is furnished with specially strong 



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