436 
Psyche 
[Vol. 85 
brood from nearby host-species colonies. In other polydomous col- 
onies where the slave-makers remained in more than one nest, the 
parasites conducted unco-ordinated raids and incurred many casu- 
alties. Several kinds of slave aggression against the slave-makers are 
described. However, slaves ‘’peacefully” augmented the slave worker 
forces of some incipient H. americanus colonies. 
References 
Allow AY, T. M. 
1979. Raiding behaviour of two species of slave-making ants, Harpagoxenus 
americanus (Emery) and Leptothorax duloticus Wesson. Animal Behav- 
iour 27: 202-210. 
Alloway, T. M., a Bu.schinger, M. Talbot, R. Stuart, & C. Thomas. 
1982. Polygyny and polydomy in three North American species of the ant 
genus Leptothorax Mayer (Hymenoptera: Formicidae). Psyche 89: 
249-274. 
Buschinger, a., & T. M. Alloway. 
1977. Population structure and polymorphism in the slave-making ant Harpa- 
goxenus americanus (Emery). Psyche 83: 233-242. 
Buschinger, A., W. Ehrhardt, and U. Winter. 
1980. The organization of slave-raids in dulotic ants; A comparative study 
(Hymenoptera; Formicidae). Zeithschrift fur Tierpsychologie 53: 
245-264. 
Del Rio Pesado, M. G.. 
1983. Polydomy in the slave-making ant, Harpagoxenus americanus (Emery) 
(Hymenoptera; Formicidae). M.Sc. Thesis, University of Toronto. 
Del Rio Pesado, M. G. & T. M. Alloway. 
1983. Polydomy in the slave-making ant, Harpagoxenus americanus (Emery) 
(Hymenoptera; Formicidae). Psyche 90: 151-162. 
Gladstone, D. E. 
1981. Why there are no ant slave rebellions. American Naturalist 117: 779-781. 
Sturtevant, a. H. 
1927. The social parasitism of the ant Harpagoxenus americanus. Psyche 34: 
1-9. 
Wesson, L. G., Jr. 
1939. Contribution to the natural history of Harpagoxenus americanus Emery 
(Hymenoptera; Formicidae). Transactions of the American Entomolgi- 
ca! Society 65: 97-122. 
Wilson, E. O. 
1971. The Insect Societies. (Cambridge, Mass.,; Belknap Press of Harvard 
University Press, x + 548 pp.) 
1975. Leptothorax duloticus and the beginnings of slavery in ants. Evolution 
29: 108-119. 
