THE SEA-LION 301 



less, the organisation of the Pinnipeds is in many respects 

 very different from that of the ordinary Carnivores, so 

 that there might be a suspicion that such resemblances 

 as do exist between them may have been due, as we have 

 seen to be the case in so many other cases, to an inde- 

 pendent origin of similar structures. 



But a certain curious and recondite similarity of in- 

 ternal structure indicates the existence of a real affinity 

 between Pinnipeds and Carnivores. In the latter — in 

 dogs, cats, civets, bears, weasels, and racoons — some 

 folds of brain substance, on the anterior portion of 

 the upper surface of the brain, give rise to a certain 

 pattern and appearance which may be compared with 

 what is known in heraldry as an " escutcheon of pre- 

 tence." A careful examination of the brains of seals, 

 walruses, and sea-lions, shows that they have also the 

 same condition of brain structure though it is not at first 

 so readily apparent as in ordinary Carnivores. Since 

 such a resemblance can hardly be the result of surround- 

 ing conditions and so have arisen independently, we 

 think it may be safely regarded as a true indica- 

 tion of the existence of a real, more or less hidden, 

 affinity. But though we thus seem forced to admit a 

 genetic relationship between Pinnipeds, and, at least, the 

 ancestors of our existing terrestrial Carnivores, it does 

 not follow that all Pinnipeds have had the same origin. 

 There are many resemblances between the sea-lions and 

 ordinary bears, and one such resemblance consists in the 

 fact that the members of both these groups possess in 

 the skull that canal for a branch of the carotid artery 

 which we have, (in our article on the American bison), 

 called the "canal in the wing-wedge bone of the skuU." 

 Such a canal is wanting in ordinary seals, and it is 

 wanting also in that aquatic modification of the weasel 



