THE PLAY OF AXIMALS. IQl 



But wko can say that sexual instinct is not responsible 

 for this ? And the same may be said of the art of the fly- 

 ing fish* Brehm says of them: " On board ship, swarms 

 of such fish can be seen at varying distances; they sud- 

 denly rise from the waves with a peculiar whirring and 

 shoot rapidly over the w^ater, sometimes rising to a 

 height of four or five metres from the surface and trav- 

 elling a hundred to a hundred and twenty metres before 

 vanishing again in the waves. Xot seldom this spec- 

 tacle is quickly repeated, for as soon as one company 

 rises, flies forward and falls, another begins to advance 

 in the same way, and before it sinks a third and fourth 

 are on tlie way. If these advances were made in a con- 

 tinuous direction w^e might suppose that their flight 

 over the waves was to escape some danger. But they 

 appear now here, now there, and keep to no particular 

 direction, but fly across and contrary to one another. 

 "We can only suppose, therefore, that it is all a play, 

 perhaps from pure exuberance of spirits, just as other 

 flsh swim rapidly over the water." Humboldt expresses 

 the same view of flying fish. The sceptic may, of course, 

 question whether all the motions described may not be 

 attributed to flight or the search for food. Yet such an 

 animal psychologist as Eomanes speaks with great as- 

 surance of the play of fishes.* He says: "Nothing can 

 well be more expressive of sportive glee than many of 

 their movements." f 



I am by no means so fully convinced as Eomanes, 

 but still I consider it highly probable that movement 

 plays are manifested by fish. Their comparatively weak 

 mental endowment is not a difficulty to me, since I re- 



* Mental Evolution in Animals, p. 382. 

 f Animal Intelligence, p. 247. 



