SOME INSECT COMMUNITIES 45 



upon the nurseries of the Wood Ant, and carry 

 off the unfortunate baby larvae as food. It is 

 quite impossible for the infuriated Wood Ants 

 to get at these tiny marauders, their bodies being 

 too large to permit them even to squeeze into 

 the diminutive galleries of their foes. Are the 

 tiny Stenammas which live on such good terms 

 with the big Wood Ants really kept as dogs to 

 fight the rapacious Solenopsis and chase them 

 into their tiny galleries? This is a question 

 which can only be answered by further careful 

 observation and experiment. 



While most Ants prey upon the nests of other 

 species, carrying off the larvae and pupae and 

 using their captives for food, some carry them 

 off purely for the purpose of making them 

 work as slaves. Thus the Ants called Formica 

 sanguined periodically attack neighbouring nests, 

 and after slaughtering and driving out the 

 adults, select and carry home those larvae and 

 pupae which will ultimately produce workers. 

 But the great slave-making species is Polyergus 

 rufescens, a species frequently met with in 

 Switzerland. 



For a striking object-lesson of the degrading 

 tendency of slavery, there is no need to go to 

 those dark corners of Africa where it is still 

 practised by man, for these slave-making Ants 

 will demonstrate it to the full. So utterly 

 dependent upon their slaves have these Rufe- 

 scent Ants become, that they have not only lost 

 most of their natural instincts, but have actually 

 undergone certain structural changes, so that 

 their mandibles have degenerated into mere 



