44 ANIMAL INTELLIGENCE. 



nationality. New nests often spring up as offshoots from 

 the older ones, and thus a nation of towns gradually 

 spreads to an immense circumference around the original 

 centre. Forel describes a colony of F. exsecta which 

 comprised more than two hundred nests, and covered a 

 space of nearly two hundred square metres. 'All the 

 members of such a colony, even those from the further- 

 most nest, recognise each other and admit no stranger.' 



Similarly, MacCook describes an 'ant town' in the 

 Alleghany Mountains of North America (' Trans. Amer. 

 Entom. Soc./Nov. 1877) which was inhabited by F. exsec- 

 toides. It consists of 1,600 to 1,700 nests, which rise in 

 cones to a height of from two to five feet. The ground 

 below is riddled in every direction with subterranean 

 passages of communication. The inhabitants are all on the 

 most friendly terms, so that if any one nest is injured it 

 is repaired by their united forces. 



It remains to be added in connection with this subject 

 that the recognition is not automatically invariable, but 

 when ' ants are removed from a nest in the pupa state, 

 tended by strangers, and then restored, some at least of 

 their relatives are certainly puzzled, and in many cases 

 doubt their claims to consanguinity. I say some, because 

 while strangers under the circumstances would have been 

 immediately attacked, these ants were in every case 

 amicably received by the majority of the colony, and it was 

 sometimes several hours before they came across one who 

 did not recognise them.' 



It may also be added that Lasius flavus behaves 

 towards strangers quite differently and much more hos- 

 pitably than is the case with L. niger. The stranger 

 shows no alarm, but, on the contrary, will voluntarily 

 enter the strange nest, and she is there received with 

 kindness ; although from the attention she excites, and 

 the numerous communications which take place between 

 her and her new friends, Sir John was ' satisfied that they 

 knew she was not one of themselves. . . . Very different is 

 the behaviour of L. niger under similar circumstances. I 

 tried the same experiment with them. There was no 

 communications with the antennas, there was no cleaning, 



