THE HARBOR SEAL 



same time by a curious undulatory movement 

 of the body, which, especially when seen head 

 on, suggests strongly an otter or perhaps a 

 caterpillar. The older individuals seem to 

 prefer an entirely different and extremely 

 singular method of progression, a specialized 

 form of locomotion not even hinted at in any 

 other mammal. They lie on one or the other 

 side, with both flippers draped obliquely 

 downwards over the chest and belly,— one 

 cannot say where one begins and the other 

 ends,— and they hitch along by a succession 

 of wave-like shuffles and jerks, emphasizing 

 the difficvilties of their progress by frantic 

 squirmings and wavings of the posterior end 

 of their body. Now and then they fall over 

 on their back in their strenuous e:fforts. I 

 have seen a medium-sized individual hitch 

 along partly on his side, using one flipper on 

 the sand, while he waved the other helplessly 

 or for balancing purposes in the air. There 

 is no suggestion of their otter ancestry in 

 these contortions. 



This one-sided method suggests that the 

 rotundity of the bodies of the seals— their 

 portly aldermanic bellies— renders it impos- 

 sible for them to reach tlie ground effectually 



165 



