GUESTS AND SLAVES OF ANTS 



ants or true ants, there are other inmates which 

 may be compared to mice in our houses. They 

 do harm, but it is difficult to get rid of them. 



On a different platform are the green flies or 

 aphides, which some kinds of ants treat as domestic 

 animals, milking them to get their overflowing 

 sweet food. The ants herd these aphides, and they 

 sometimes take them into underground stables 

 when winter comes. 



Slave -Keeping 



If slave-keeping among ants occurred once or 

 twice, we might think it was some strange freakish- 

 ness among the little people, but there are many 

 instances and many stages of the " institution." 



A fertilized queen of the red ant, Formica san- 

 guinea, may fall after her nuptial flight into a nest 

 of black ants, Formica fusca, where there is no queen. 

 She is received and fed, and the eggs which she 

 lays are tended. A mixed colony arises, with the 

 reds as masters and the blacks as slaves, the former 

 being more active in external operations and the 

 latter in the discharge of domestic duties. As the 

 blacks do not multiply, the reds make sallies and 

 bring back pupae from neighbouring nests of blacks. 

 Those that are not eaten grow up to slavery. Some- 

 times, however, the slaves gradually decrease in 

 number, and the mixed colony becomes a pure red 

 colony. In this case, therefore, the slave-keeping 

 need not be more than temporary. 



In the Amazon ants (e.g. Polyergus rufescens in 

 Europe and P. lucidus in America) the " institution 



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