234 
Psyche 
[Vol. 92 
mated workers showed intermediate activity. We suggest that the 
oocytes of unmated workers may be destined to become trophic 
eggs. 
None of the 230 ants dissected from an apparently incipient col- 
ony was inseminated; the level of ovarian activity in such individuals 
was high. 
Foragers from different nests were not indifferent to each other 
after contact, usually running away but sometimes fighting. Despite 
this antagonism between foragers, the foraging area for two nests 
studied intensively extended beyond the figure subtended by neigh- 
boring nests. Foraging trips extended significantly further in 
November than in September, probably due to a decline in the food 
supply. 
Foragers had a strong and statistically significant tendency to 
take the same direction in successive foraging trips, i.e., they show 
foraging-direction fidelity. 
We saw ants carrying others from one nest to another in three 
regions of our study area, and studied their behavior in one of these 
areas intensively. In this region, we saw this carrying take place in 
September in each of the possible six directions between three nests. 
But most traffic was into one of them, nest 60. The resulting inter- 
mixture of ants between nests was considerable, as shown by mark- 
ing experiments. Tests for worker hostility to ants from other nests 
showed nest 60 to be the least hostile, with the adjacent nest 61, not 
one of the three nests linked by carrying, showing a high level of 
intolerance to strangers. In November, however, nest 61 included 
ants originally marked in the other three nests. 
“Carrier” ants had less ovarian activity than those they carried, 
and, from the additional fact that the same carriers made repeated 
trips, seem to form a relatively small group within the colonies. 
It is uncertain whether the nests linked by internest movements 
represent multi-nest colonies, or whether such activity can poten- 
tially involve any neighboring nests. 
Literature Cited 
Buschinger, A. 1978. Genetisch bedingte Einstehung gefluegelter Weibchen bei 
der sklavenhaltenden Ameise Harpagoxenus sublaevis (Nyl.) (Hym., Form.). 
Insectes Sociaux, 25: 163-172. 
Buschinger, A., and T. M. Alloway. 1977. Population structure and polymor- 
phism in the slave-making ant Harpagoxenus americanus (Emery) (Hymenmop- 
teran: Formicidae). Psyche, 83: 233-242. 
