FISHES 



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by means of which the fish walk over the sea floor or may- 

 even climb rocks. 



In the herring-like Flying Fish (Exocoetiidae) the pectoral 

 fins are transformed into large wings, which may extend 

 backwards as far as the tail and enable the fish to plane 

 through the air. A certain amount of controversy has 



Flying Fish 



arisen as regards the manner by means of which the fish 

 sustains itself in the air. Some authorities are of the 

 opinion that the wings are merely utilised as gliding 

 planes, whilst others are definitely of opinion that the 

 fish vibrates its fins in the way a bird does with its wings, 

 only much faster. According to J. R. Norman, the 

 prolonged aerial excursions of the Flying Fishes are 

 improvements on the spasmodic jumps of other fishes. 



