1906.] Wheeler, Founding of Colonies by Queen Ants. 93 



to seek the society of workers and to rely on them both for her own 

 sustenance and that of her brood. Hence it is not surprising to find 

 that the females of some species may return after the marriage flight 

 to seek readoption in the parental nest. In other cases fertilization 

 may take place within the nest and the females, after losing their 

 wings, remain as so many additional mothers to re-enforce the re- 

 productive energies of the colony. One or both of these methods is 

 adopted by most of our species of Formica, and must, indeed, be as- 

 sumed in order to account, first, for the normal occurrence of more than 

 one dealated female in nearly every large colony; second, for the mul- 

 tiplication of nests by a single colony and third, for the longevity of 

 certain colonies far exceeding that of individual queens. From sin- 

 gle colonies of F. gnava in Texas I have taken from 30 to 50 dealated 

 females, and Wasmann 1 dug 60 old females from a single nest of the 

 European rufo-pratensis. He also publishes a number of notes on the 

 great tendency of F. rufa to form nests by a process of budding, so to 

 speak, from a single original formicary, a phenomenon that had been 

 previously observed by Forel and others, and also in the North Amer- 

 ican exsectoides by McCook. (Vide supra p. 72) Forel 2 mentions a 

 colony of F. pratensis which he has had under observation for nearly 

 forty years. It is extremely populous and has taken possession of a 

 whole pine grove. On digging into this nest recently he found ferti- 

 lized and unabraded females that certainly must have been much 

 younger than the colony. 



We may conceive that the next step in the phylogenetic develop- 

 ment of temporary social parasitism was taken when, after descending 

 from their nuptial flight, the females sought adoption in nests of their 

 own species but belonging to alien colonies. As such adoption may be 

 easily effected in artificial nests of some species of ants, there is no rea- 

 son to suppose that it does not occur in wild colonies. In fact, Was- 

 mann's observations^ go to show that in Europe such adoptions not 

 infrequently occur between workers of one and females of another 

 variety or subspecies of F. ruja. He says that ' ' in rufa and pratensis 

 colonies, but especially in rufo-pratensis , rufo-truncicola, etc. females 

 with rufa, pratensis or truncicola coloration are often found together." 

 Such conditions, which can be explained only as the result of adop- 

 tion, lead to the final phylogenetic stage represented by the adoption 

 of a female of one species by workers of another. It must be admitted 



' Ursprung u. Entwickelung der Sklaverei bei den AmeiEen, loc. cit., p. 196. 

 ^ Ueber Polymorphismus und Variation bei den Ameisen. Zool. Jahrb. Suppl.. VII, 1904, 

 p. 5 80. 



^Ursprung u. Entwickelung, etc., loc. cit., p. 198. 



