communication exists between the two passages as in our- 

 selves. 



Although all whales are carnivorous they are far from com- 

 peting for the same food in all cases. The sperm whales 

 feed largely on the giant squids and cuttle fishes, with 

 which we have such slight acquaintance because they live at 

 the bottom of the deeper parts of the ocean. To secure food 

 of this sort the sperm whales are provided with long narrov/ 

 jaws and strong teeth, but of the nature of the combat be- 

 tween these giants we can easily imagine more than we know. 

 The beaks of the squids in the stomach of the v/hale are proof 

 that the whale is often victorious; but may v/e not suppose 

 that he must run some risk of being ignominiously drowned 

 in the entwining arms of the squid ? 



Other whales are entirely lacking in teeth. Teeth would 

 indeed be utterly useless on the microscopic molluscs upon 

 which these whales chielly feed, and in their place there 

 hang down from the sides of the upper jaw long plates of 

 baleen or "whalebone" which are frayed out into fine hairs 

 on the inner edge. Plowing through the sea with mouth 

 wide open many thousands of minute pelagic animals are 

 gathered into this rapacious maw. The jaws then close, the 

 baleen plates folding down inside the great lower lips, and a 

 two-ton tongue rises and presses the water out through the 

 meshes of the baleen, which act as a sieve to retain each mi- 

 nute particle of food. Not the least surprising feature of 

 this whole apparatus is the small size of the oesophagus, 

 which is not more than two inches in diameter, and so 

 contrasts oddly with the cavernous mouth, although perfectly 

 adapted to the food which it receives. 



If we turn once more to the evidence of embryology we 

 shall see that teeth are formed in the jaws of the embryos 

 of baleen whales and then absorbed to make room for the 

 whalebone, very convincing proof that these whales are the 

 most extremely specialized of ail the Cetacea. Indeed it 

 would be hard to find any vertebrate animal which has un- 



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