MENTAL EVOLUTION OF MAN 207 



chrysalis with its complete adult series of wings and 

 muscles, it has also the nervous mechanism by which 

 these parts are mechanically controlled. A ground- 

 wasp deposits its eggs in a small burrow in which it 

 places also a caterpillar or a grasshopper paralyzed by 

 stinging, so that when the larva is hatched from an egg 

 it finds an ample supply of fresh food provided by a 

 complex series of its mother's acts that seem to be 

 directed by conscious maternal solicitude. When the 

 larva passes through the later stages of development 

 and makes its way to the open air as a fully formed 

 adult, it in its turn may go through the same course of 

 action as its parent, but it is clear that it cannot have 

 any remembrance of its mother's work or any personal 

 knowledge of the value of burying its own eggs in a 

 chamber with a living prisoner to serve as food. It 

 was an egg when its parent did these things ; as a parent 

 itself it does not remain on watch to see how beneficial 

 or fruitless its acts may be. A mechanism produced 

 by nature's methods, the ground-wasp behaves as it is 

 capable of working with its inherited structure and its 

 inherited instinctive powers of coordination and sensa- 

 tion. 



The complex lives of communal insects like ants and 

 bees bring us to the level of mentality where an under- 

 standing of causes and effects seems to be the guide 

 for conduct. Nevertheless the facts do not warrant 

 the assumption that reason and intelligence play any 

 part in the mental life of these creatures, as they do in 

 the lives of man and the apes. Because we ourselves 

 can see the utility of the definite and peculiar behavior 

 of the queen and the worker, there is no logical necessity 



