534 PROCEEDINGS OF THE ACADEMY OF [Oct., 



Ants hatched and reared to the age of twenty days with no 

 association with any other ant received and affiliated with a queen 

 of their lineage, though with some tentative nabbing. 



Into a cell containing eight workers, of which equal numbers 

 had been together reared from pupie of two colonies, C and E, I 

 introduced a C colony queen deprived of smell-sense. She was 

 dragged away from the larvse pile, but was not injured, and in six 

 hours she was a fully accepted member of the mixed group. 



Probably the odor discerned by the ants is something different 

 from any discovered by human nostrils. 



The odor ju'eferred by the individual ant is determined by associa- 

 tion, naturally during the first few days of its active life. Cal- 

 lows no more than three days old, having spent these days with a 

 queen alone, with workers alone, or with both queen and workers, 

 will thereafter withdraw from or fight any queen or worker belong- 

 ing to any colony other than their own ancestral one, or those 

 represented in their earliest nurses. 



Pupre of the E colony were isolated the last thirteen days of 

 their pupa-stage, and their first meeting with any ant was when 

 they were two days old, and was with a queen of the colony. 

 Within an hour the queen and the callows had perfectly affiliated. 

 This queen had not been deprived of smell-sense; but during the 

 long isolation of the pupa3, the E colony odor that earlier overlaid 

 them had doubtless been dissipated, and they therefore presented 

 to her nothing stronger than their own inherent odor as callows. 

 Young callows from pupoe that have been isolated during the 

 whole or nearly the whole pupa-period are safe in any colony. The 

 immediate affiliation of these callows with an alien queen is the 

 point to be here observed. 



I sequestered pupa3 from colony C and isolated the emerging 

 unlicked callows. When these uunursed callows were two days 

 old I put them into a Petri cell with a colony E queen and workers 

 deprived of the smell-sense. The callows made no attack on the 

 alien adults, but congregated beside the queen or workers as ami- 

 cably as if all were of their own lineage. But callows likewise 

 sequestered, isolated and reared to five days old with no association 

 w^ith other ants, could not be induced to affiliate with aliens. They 

 established for themselves a criterion of correct odor, and withdrew 

 from or seized any ant varying from their standard. 



