404 AISTNTJAL REPORT SMITHSONIAN INSTITUTION, 195 5 



queens emerge from their cocoons and receive the differentiated re- 

 sponses of workers, and it becomes an actuality when the males emerge 

 a few days later. Emergence of the males sets off a maximum raid, 

 somewhat more vigorous than with an emerging worker brood, and the 

 colony moves off divergently on different raiding trails. Colony di- 

 vision thus may be understood as a special case of the initial emigration 

 of a nomadic phase. 



One difficult question concerns the fact that, although about six 

 young queens normally emerge in a sexual brood, colony division never 

 seems to produce more than two daughter colonies. The fact is that 

 ordinarily only one of the young virgins can get established in a 

 daughter colony — or two of them if the old queen is superseded. The 

 entire process, including both the ascendancy of the successful queen 

 and the rejection of the others, seems to be based on worker reactions 

 to queen odors of different strengths and attraction, as well as on possi- 

 ble disturbance effects. As the two new daughter colonies move off 

 divergently, each with its queen, the several unsuccessful young queens 

 and perhaps also the discarded old queen are held behind ("sealed 

 off") by workers in an interesting series of reactions which ends in 

 their seclusion and final abandonment to the elements. 



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