POWER OF RECOGNITION AMONG ANTS. 243 



their introduction. They were doubtless the progeny of other 

 queens than those which produced the early acquaintances of the 

 Cremastogasters in nest 63. 



HYPOTHESIS. 



From such data as is here presented, correlated with records of 

 past years, it is possible to diagramatically represent the proba- 

 bilities that an ant, isolated from the pupa-stage, would encounter 

 a known odor at a first meeting with another ant of her colony. 

 If the odor of a queen be unchanging, if she impart odor to all 

 her eggs, if that odor be perceptible in the inert young, and if 

 from the beginning of the active life of the worker there be a 

 progressive change in the inherited odor borne by her, then 

 from each summer's deposit of the queen's eggs there would be 

 in the following summer more than one odor among the workers, 

 because all the eggs of a queen are not hatched during the sum- 

 mer in which they are deposited. We may suppose a young, 

 fertilized queen, the founder of a colony, to deposit eggs in her 

 isolated cell in July, and to have reared her first small brood in 

 not less than sixty days. 1 The eggs laid by her in the latter 

 part of summer or early autumn would reach the larval stage in 

 late autumn, and in that stage would be carried over to the next 

 June, to hatch as ants in summer. While this second brood was 

 developing, the first brood would have advanced to the odor of 

 ants many months old. Their odor would then be unknown to 

 an ant newly hatched from the queen-mother's egg and having 

 the odor of its own body as its only criterion of ant-odor. Suc- 

 ceeding years would bring similar conditions. 



In Sir John Lubbock's nests, one ant-queen lived to her four- 

 teenth, and another to her fifteenth year ; but the purpose of 

 the diagram is reached by the supposition that the queen lives 

 ten years. 



1 For time of incubation of eggs, larval period and pupa-stage in Slenannna ful- 

 viun, see " A Study of an Ant," A. M. Fielde, Proceedings of the Academy of Sciences 

 of Philadelphia, September, 1901, p. 430. The time of incubation appears to be 

 twenty days for all ants that I have observed ; the larval period may be extended to 

 at least one hundred and forty days in a high temperature, and probably to a much 

 longer time in cold weather ; and the pupa-stage occupies about twenty days. I 

 have known the larval period to be passed in twenty days. 



