80 A NATUBALIST IN CELEBES ch. ii 



Not being endowed with the wisdom of the crab, I 

 wondered why, to escape from such an enemy as they 

 evidently took me for, they did not immediately plunge into 

 the water and hide beneath the rocks. Perhaps they have 

 found that it is safer to trust to their powers of flight 

 from rock to rock, which were, it is true, good enough for 

 such an enemy as I was, than by plunging in the waters, to 

 run the risk of falling victims to larger crabs and other foes 

 that lurk in the rocky pools. 



The little jumping fishes [vide Frontispiece) are well 

 known upon the shores of all the Indian seas. They, like 

 theii- crab-comrades, appear to consider that their safety 

 lies above the water rather than in it, for they never attempt 

 to save themselves when disturbed by plunging into the 

 sea. 



Their position is usually one of clinging to the edge of 

 the rocks or mangrove roots by their fins, with their tails 

 only in the water. When alarmed they make a spring 

 by means of their bent, muscular, pectoral fins, and then 

 skim across the water by a succession of short jumps until 

 they reach a place of safety. 



The fact that they live the greater part of their lives 

 with their head and gills out of water suggested to me an 

 investigation of their respiratory organs, as I thought it pos- 

 sible that they might possess some interesting modifications 

 of the swim-bladder to enable them to breathe the air. It 

 was not, however, until the Meeting of the British Association 

 at Manchester in 1887 that an explanation of the mystery 

 of their respiration occurred to me — namely, that the respi- 

 ration is mainly performed by the tail. Since then Professor 

 Haddon has been carrying on some experiments in Torres 

 Straits and has shown that this explanation is correct (29). 



It seems at first sight a very extraordinary thing that a 

 fish should have become so modified by change of habit as 



