138 Instinct and Intelligence 



behind on a ledge of rock and called loudly to 

 its companions for help. One of the largest 

 males of the troop came slowly to the young- 

 ster's aid and led him to a place of safety. Be- 

 haviour of this kind seems to imply intelli- 

 gence, the old ape's instinctive action becom- 

 ing modified by energy discharged from his 

 visual and auditory neopallial centres by stimuli 

 derived from cries, and the apparent peril in 

 which his young companion was placed. Most 

 of us have witnessed or heard of the surprising 

 antics which performing apes go through at a 

 sign or command of their keepers; but it is 

 doubtful if they utilise acquired habits of this 

 kind for their own advantage or to promote the 

 well-being of their fellow-creatures. 



