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Dwellers of the Sea and Shore 



Here, In a word, is the real reason why the flatfish Is 

 Indistinguishable when It is motionless. The most 

 striking of its adaptative features, however, Is the posi- 

 tion of its eyes. In the common fishes familiar to 

 everybody these organs, like those of the higher ani- 

 mals, are situated one on each side of a middle line 

 dividing the right and left half of the body. But the 



ROCK CRAB CONCEALING ITSELF IN THE SAND. THE ANIMAL IS IN THE CENTER OF 

 THE PICTURE. THE FORE PART OF ITS BODY AND THE ENDS OF ITS CLAWS ARE 

 THE ONLY PORTIONS EXPOSED. 



flounder Is almost a freak; Its eyes are both on one side 

 of its head; in other words, on that side of its body 

 which it keeps uppermost. When one considers, more- 

 over, that this creature is hatched as a transparent 

 fish, swimming vertically in the water, with an eye on 

 each side, the foregoing circumstances seem all the 

 more striking. Nevertheless, it should be observed 

 that these changes are not more marvelous than the 



