DUBLIN] SLA VE- MA KING HA BITS OF ANTS \ 3 7 



younger masters increased. This if continued would, of course, 

 in a comparatively short period lead to the formation of a pure 

 sanguinary colony. In some cases where the sanguinary ants 

 are already firmly established this actually takes place. More 

 often, however, this does not occur; for from time to time the 



Fig. I. — The common red ants, Formica sanguinea, with pupae. Photographed by 

 Dr. O. S. Strong. 



slave-makers make sallies upon neighboring nests, robbing 

 them of their young. Brought into the nest, these serve in part 

 as food, but a large portion always remains to be raised into 

 slavery. By this means is the mixed character of the colony 

 preserved. 



In such a well developed community it is interesting to observe 



