SO- ANTS. 



on these nests, the males and pupae were promptly seized and thrown 

 a\vav and the females were also seized, but less promptly, and also 

 rejected. Some of the latter that had managed to enter the nests were 

 soon brought out and dumped at a distance of several decimeters from 

 the entrances. I watched the nests for some time and although a few 

 of the females were not brought out, I am, of course, unable to state 

 whether thev were subsequently adopted, killed in the galleries, or 

 ejected. It appears, therefore, that the acceptance of the parasites by 

 the Tetniiiitiriinn under natural conditions is not a* immediate and 

 simple as the observations of Adlerz and Wasmann on artificial nests 

 would lead one to suppose. The fact that Anergatcs is so rare an ant, 

 notwithstanding its sporadic colonies produce enormous numbers of 

 females in regions inhabited by myriads of Tctramorium colonies, shows 

 that permanent adoption is not easily effected. Were the contrary the 

 case, Tetramorium ccspitum would itself become a rare, if not extinct, 

 species. 



There can be no doubt that of the seven permanent social parasites 

 above enumerated, Anergatcs is the most specialized and degenerate. 

 This is clearly shown in the ergatoid and nymphoid structure of the 

 male and the structure of the head in both sexes. All the other 

 species agree in being in a less advanced stage, although they, too, have 

 lost the worker caste. This loss may be said to be due to disuse, but 

 it followed necessarily upon the reduction in size of the male and 

 female, and this condition in turn was probably initiated by the same 

 causes that have led to the dwarfing of the queens among the temporary 

 parasites. Forel, Lubbock and Wasmann are inclined to believe that 

 Anergatcs represents a form that was once dulotic. Lubbock says: 

 " In Anergatcs, finally, we come to the last scene of this sad history. 

 We may safely conclude that in distant times their ancestors lived, as 

 many ants do now, partly by hunting, partly on honey ; that by degrees 

 they became bold marauders and gradually took to keeping slaves; that 

 for a time they maintained their strength and agility, though losing 

 by degrees their real independence, their arts, and even many of their 

 instincts ; that gradually even their bodily force dwindled away under 

 the enervating influence to which they had subjected themselves, until 

 they sank to their present degraded condition weak in body and mind, 

 few in numbers, and apparently nearly extinct, the miserable repre- 

 sentatives of far superior ancestors, maintaining a precarious existence 

 as contemptible parasites of their former slaves." This interpretation 

 of Anergatcs as a very degenerate dulotic ant seems to have been sug- 

 gested by the obvious dwindling of the worker caste in Strongylog- 



