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THE NATIONAL GEOGRAPHIC MAGAZINE 







visibility of the fish. Contrast, for in- 

 stance, the color plans of the Rock Hind 

 and the bizarre Rock Beauty (Plate II). 



CHAMELEONS AMONG THE FISHES 



These groupers, rock fishes, and hinds, 

 furthermore, have the power of under- 

 going complete color changes almost in- 

 stantaneously. The color tone becomes 

 lighter or darker and the markings be- 

 come bold or fade and disappear. Such 

 color changes can be seen to advantage 

 in individuals kept in an aquarium. 

 There can be no doubt that in the fishes' 

 natural environment they adapt it to the 

 bottom it is swimming over, and, further, 

 that inconspicuousness may aid in its 

 getting a full meal at the expense of its 

 smaller associates. 



There is a related fish which has a 

 color pattern almost exactly like that of 

 the Rock Hind, namely, the Spotted 

 Hind. The principal technical difference 

 between the two is that one has minute 

 scales on its maxillary and the other has 

 not — a characteristic about as obvious to 

 the layman as what the fish is thinking 

 about. The Spotted Hind's squarish tail 

 fin, with a broad, blackish border, affords 

 an amateurish, but simpler, way of tell- 

 ing it. 



The fish life of warm shores is one of 

 contrasts. In contrast to the big-mouthed 

 sea basses, there are species, usually slug- 

 gish, which have very small mouths, de- 

 pending for their subsistence on the great 

 abundance of small sea animals found 

 about tropical reefs and ledges, or sea- 

 weeds. To capture such small creatures 

 does not require great agility. 



THE MALE SEA-HORSE HAS AN INCUBATOR 

 POUCH 



The sort of life they lead has probably 

 been taken up gradually, through long- 

 periods of time, and many of them have 

 meanwhile acquired remarkable and 

 sometimes quite unfishlike characters of 

 form and structure. None is stranger 

 than the little Sea-horses (Plate IV), 

 with body encased in rings of bony mail, 

 horse-shaped head set at right angles, 

 and prehensile tail to grasp the seaweed 

 where they are hiding, body floating up- 

 ward erect in the water. 





