LIMITATION OF FAMILIES 133 



civilisation being developed and of much more complex instincts 

 being formed. When we think of the elaborate ordering of a com- 

 munity of ants, of the care devoted to the young, of the capture of 

 other ants and their use as slaves, of the domestication of aphides 

 and their use as milch cows, of the cultivation of fungi to be used 

 as foods, it is plain that there is nothing comparable until we reach 

 the highest organisations of civilised man. And yet these have 

 come about as a by-product of the formation of families. 



