448 THE EVOLCTTIOlf OF MAN. 



instance, Sloths and Armadillos) and the most intelligent 

 animals of the same group (for instance, Dogs and Apes), 

 seem much more considerable than the intellectual dif- 

 ferences between those lowest Placentals and the Pouched 

 Animals, or even the lower Vertebrates. Those differences 

 are, at any rate, much more considerable than the dif- 

 ferences in the intellectual life of dogs, apes, and men. And 

 yet all these animals are allied members of a single class.^** 

 This fact is shown to a yet more surprising degree in 

 the Comparative Psychology of another class of animals, 

 which is specially interesting for many reasons, that of 

 Insects. It is well known that many Insects exhibit a 

 mental capacity approximately as highly developed as is 

 possessed by Man only of the vertebrate group. It is needless 

 to speak of the celebrated organized communities and states 

 of Bees and Ants ; every one knows that very remarkable 

 social arrangements occur among these, such as occur in an 

 equal degree of development only in the higher races of 

 men, and nowhere else in the animal kingdom. I will only 

 aUude to the civil organization and government among 

 Monarchical bees and Republican ants, to their division 

 into various orders : the queen, the drone nobility, the 

 workers, the nurses, soldiers, and so on. Among the most 

 remarkable phenomena in this extremely interesting field of 

 life, is certainly the cattle-keeping of certain Ants, which 

 tend plant-lice for the sake of their milk and regularly 

 coUect their honey-juice. Even more remarkable is the 

 slave-holding of the large red Ants, which steal the young 

 of the small black species and rear them to slave-labour. 

 It has long been known that all these civil and social 

 arrangements of the Ants were originated by the systematic 



