THE VERSATILE GURNARD 



alongside the four spines of the first dorsal fin. 

 When the fish begins walking, these two rays 

 separate laterally and act as balancers, one on 

 each side, forming an angle of about forty-five 

 degrees. If the gurnard turns quickly or trips up, 

 one of the two rays dips down on the corrective 

 side, exactly as a person's outstretched arms assist 

 in regaining lost balance. The motion pictures 

 which we were able to secure of the walking gur- 

 nard show all of these unpiscine refinements. 



When Professor Moseley went on the classic 

 Challenger expedition, he took his trout rod with 

 him, and in the Cape Verde Islands he found flying 

 "gurnats," as he called them, abundant. He 

 writes : 



*'I hooked one, however, near the surface, when 

 fishing with a rod and tackle for small mackerel 

 and silver fish. This was quite a novel experience 

 in fishing. The flying fish darted about like a 

 trout and then took a good long fly in the air, and 

 in an instant was down in the water again and 

 out again into the air, and being beyond my skill 

 in playing with such light tackle, soon shook itself 

 loose and got free. " 



As I dived day after day, and walked about the 

 coral reefs of Haiti, I was ever more deeply im- 

 pressed with the astonishing uses to which the 

 fins of fish are put. I saw a dozen or more species 

 which actually, and not as a mere figure of speech, 

 deserve the term walking, while in as many more 

 I watched the pectoral fins being used to turn 



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