44 ./ATS. 



lion of strange queen-, even of the same species but from alien colon ie>, 

 often meets with insuperable opposition on the part of the workers, 

 and, as a rule, female ants have to overcome even greater hostility 

 when they seek adoption in colonies of alien species. There are, never- 

 theless, at least three different methods of overcoming this hostility and 

 of effecting an adoption, and each of these is characteristic of one of 

 the forms of mixed colony. I shall consider these in this and the two 

 following chapters under the heads of temporary social parasitism, 

 dulosis, or slavery, and permanent social parasitism. The following 

 diagram will serve to illustrate the foregoing account of the different 

 types of adoption, their supposed phylogeny and their relations to one 

 another. The relations will be made clearer by the facts recorded in 

 the sequel. 



Independent Types Dependent Types 



Redttndant Type 

 (Attii) 



Primitive Independent Type g-> Facultative Adoption of queen 

 (Most Formicidae) by workers of same species 



Obligatory Adoption of queen 

 by workers of same species 



I 



Obligatory Adoption of queen 

 by workers of another species 



Temporary Social Parasitism jjl Slaverv, or Dulosis 

 (Tutelary Parasitism) T (Pupillary Parasitism) 



^ ^ 



Permanent Social Parasitism 



In the cases of temporary social parasitism the initiative of the 

 queen ant is shown with great clearness. She actively seeks adoption 

 in the colony of another species and permits the alien workers to bring 

 up her first brood of young. The full benefits of this form of para- 

 sitism, however, can be secured only by the elimination of the queen 

 of the host species, for if this insect remained in the colony she would 

 continue to produce young and the nurture bestowed on these by the 

 workers would seriously interfere with the development of the para- 

 site's own progeny. As will be shown presently, different species seem 

 to have developed different methods of getting rid of the host queen. 



