THE COLONY AS A WHOLE. 51 



In the laboratory at Baton Rouge it was our custom to put all sur- 

 plus queens into one colony, kept for the purpose, and leave them there 

 until wanted. As many as several dozen queens were sometimes in 

 this colony at once, all living peaceably together, and with the num- 

 ber of queens sometimes exceeding the number of workers. 



Queens will frequently leave the nests with the workers, and will be 

 observed in the foraging trails. Ten queens were collected in 30 min- 

 utes from a large trail of workers at New Orleans, La., during Jan- 

 uary, 1911. These were quite remote from the nearest nest. Any 

 colony will immediately accept a strange queen without hesitation, 

 and it is probable that a constant interchange of queens takes place 

 between different colonies. 



THE COLONY AS A WHOLE, 



In size the colonies may vary from a dozen to many thousands of 

 individuals and the number of queens present in a colony may vary 

 from one to many hundreds. Although the Argentine ant is particu- 

 larly aggressive and a hard fighter when coming in contact with most 

 other species of ants, there is no apparent antagonism between sepa- 

 rate colonies of its own kind. In fact, in heavily infested areas the work- 

 ers and queens are so intermingled that the individuality of colonies 

 is entirely lost sight of and all colonies appear to become part and 

 parcel of one enormous community. In this respect the species may 

 be said to have a more perfect social organization than even the honey 

 bees, colonies of which are very distinct and the individuals of which 

 usually repel with alacrity any visitor from another colony. 



SEASONAL HISTORY. 



In order to connect the scattered and individual life histories 

 already given into one united whole it may be well to take a glance at 

 the changes which occur in the ant colonies with the different seasons. 



WINTER COLONIES. 



The tendency of the Argentine ants to segregate into large winter 

 colonies is very pronounced, and during the winter small colonies 

 are very scarce, while nearly every protected situation will reveal 

 the presence of enormous colonies. The stages which are represented 

 in the nest are queens, workers, eggs, larvae, and worker pupss. 

 During cold weather very few changes occur. The egg and larval 

 periods are very much lengthened compared to the summer rate of 

 development. The workers themselves move very little, and a large 

 colony will subsist upon a small supply of food for long periods. 

 During warm days heavy trails of workers emerge from the nests 

 and carry back anything available for food. Except for this the ants 

 may be considered as almost in hibernation during the winter months. 



