Wars and Slavery in the Animal Kingdom. 87 



of this kind is related by Forel in his "Fourmis de la 

 Suisse." One day he brought a handful of F. pra- 

 tensis to a confederate colony of sanguineas and pra- 

 tensis; the pratensis of this colony, two months 

 before, had been taken from the same pratensis nest 

 to which the new arrivals belonged.^ What happened ? 

 Immediately the new pratensis were fiercely attacked 

 by the sanguineas^ because they were recognized as 

 enemies by means of the "smell at contact."^ The 

 old pratensis seemed to recognize their sisters but 

 faintly. They met them with suspicion and did not 

 assist them, although on the other hand they did not 

 take part in the fight. But soon they began to carry 

 the new arj-ivals into the confederate nest, as if they 

 belonged to it. The number of the pratensis was thus 

 increased considerably, outnumbering even the san- 

 guineas. Although the latter continued their hos- 

 tilities against the newcomers for several days, and 

 mutilated and killed several of them, it never occurred 

 to the old pratensis to make common cause with their 

 maltreated "sisters" against their natural enemies. 

 They allowed the sanguineas to have their own way, 

 until the survivors had gradually acquired the nest- 

 smell of the confederacy. In the course of a week 

 "peace" was restored, and the strangers were treated 

 henceforth, also by the sanguineas, as inmates of the 

 same colony. 



If ants had the power of rational reflection, if they 



^) Both had been taken from the pratensis nest when fully de- 

 veloped and not as pupae. Otherwise this example would be out of 

 place when speaking of "allied colonies." 



2) By this term Forel expresses very well the peculiar sensation of 

 ant feelers. 



