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Psyche 
[Vol. 88 
North America (Alloway, 1979). The observations reported here 
took place in artificial nests in the laboratory (Alloway, 1979) and 
utilized colonies of H. americanus containing one or both of its host 
species, L. ambiguus and L. longispinosus. The colonies were 
collected in the regional municipalities of Halton and Peel, Ontario. 
Intermittent observations of activity inside H. americanus nests 
revealed that slave-maker queens and workers occasionally convey 
fluids to their slaves by means of abdominal trophallaxis. Donors 
characteristically raise their abdomens and assume a stereotyped 
posture, similar to that seen during “sexual calling” (“Locksterzeln”) 
in other leptothoracine ants (Buschinger and Alloway, 1979). I was 
unable to ascertain whether the sting is exposed in the present 
context, as it is during “sexual calling” and “tandem calling”, a 
similar behavior used during nest-mate recruitment in some lepto- 
thoracine ants (Moglich et al., 1974). While maintaining this 
posture, the donor secretes a droplet of clear fluid from the tip of 
her abdomen, and holds it there, at times for several minutes. Slaves 
do not seem to be attracted from any appreciable distance by this 
behavior, but those close by turn and antennate the donor’s 
abdomen, apply their mouthparts to the tip, and consume the 
droplet. As many as three slaves have been observed to attend a 
donor simultaneously in this manner, clustered about her abdominal 
tip and attempting to consume the droplet. On one occasion, the 
droplet was removed from the donor’s abdomen by three workers in 
concert, held between their mandibles momentarily, and then 
consumed. Once the droplet is removed, the donor lowers her 
abdomen, and both donor and recipients appear to resume normal 
activities. There is no indication that slaves ever solicit this fluid; 
and to date, the reverse, slaves donating to slave-makers, has not 
been observed. Similarly, this behavior has never been observed in 
laboratory colonies of the host species. The nature of the fluid 
transmitted is unknown. It may be ovarian in origin, since H. 
americanus workers will lay eggs, even in queenright colonies 
(Buschinger and Alloway, 1977). The frequency of this behavior is 
uncertain. It appears to be rare, since frequent observations of 
colonies for other purposes have seldom encountered it. However, 
no detailed behavioral repertoire study of this ant has been con- 
ducted. 
The fact that H. americanus employs a characteristic posture 
during abdominal trophallaxis suggests that this behavior may have 
