1982] 
Alloway, Buschinger, Talbot, Stuart & Thomas 
261 
Discussion: 
These data establish two important points. First, polygyny involv- 
ing multiple inseminated queens occurs in some nests of L. am- 
biguus, L. curvispinosus, and L. longispinosus; and polygynous 
nests imply the existence of polygynous colonies. Polygyny in these 
three members of the subgenus Leptothorax sensu stricto as well as 
in L. schaumi and L. flavicornis (Buschinger, unpublished observa- 
tions) is somewhat surprising in that the majority of European 
members of the subgenus are strictly monogynous (Buschinger 
1967). The form of polygyny exhibited by L. ambiguus, L. curvispi- 
nosus, and L. longispinosus is also interesting in that the frequent 
joint presence of A- and b-queens indicates that colonies of these 
species can adopt young conspecific queens. We will argue below 
that this tendency to adopt queens is important for understanding 
the evolutionary origins of parasitic colony foundation. 
Second, although our dissections of workers in queenless colonies 
which produced female pupae revealed that some workers lay eggs, 
our failure to find any workers with a spermatheca indicates that 
ergatomorphic reproductive females of the kind seen in the slave- 
maker Harpagoxenus sublaevis are at least not common in L. am- 
biguus, L. curvispinosus, and L. longispinosus. 
Polydomy 
This latter finding suggested two possibilities which are not mutu- 
ally exclusive: 
a. Some queenless nests of these species which produce broods 
containing female pupae may be parts of polydomous colonies. 
In such cases, the female pupae would be the progeny of queens 
located in other nests at the time of collection. 
b. Some queenless nests may represent declining colonies with no 
queen. The female pupae are the offspring of a dead queen. 
Materials and Methods 
We collected groups of acorn nests which were very close together 
in nature and brought the nests back to the laboratory where the 
ants were established in artificial nests. We then arranged the artifi- 
cial nests in arenas to duplicate the spatial arrangement of the natur- 
al nests and observed the ensuing behavioral interactions. As 
controls, we tested the effect of placing nests from different parts of 
