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Psyche 
[March 
with proper division of labor among cofoundresses we would expect 
an even higher number of cells. This is not the case; there is a loss 
in efficiency due directly to dominance reactions on the nest, which 
we will discuss later. Larger nests also are produced in colonies by 
both P. fuscatus and P. canadensis when foundress associations are 
large. 
Bequaert (1923) and Isely (1922) reported similar findings in 
their investigations of P. pallipes and P. metricus respectively, al- 
though an efficiency loss was not as apparent in colony founding by 
either of these species. Rau (1940) found highly significant differ- 
ences in cell numbers of single versus multiple cofoundresses in his 
studies of P. annularis. 
Cofoundress Characteristics 
Several anatomical and behavioral characteristics are demonstrated 
by each cofoundress. Each such female 1 ) is a fertile producer of 
diploid eggs (Dirks and Hermann, 1975a) ; she attempts to estab- 
lish her dominance by 2) demonstrating unilateral aggressiveness 
toward other cofoundresses (i.e., biting, over-under posture, sting- 
ing) ; and 3) she is capable of rigid gastral movements, known as 
abdomen (tail) wagging (Eberhard, 1969). 
Insemination the previous fall or in the following spring (Her- 
mann, Gerling and Dirks, 1974) appears to be quite successful in 
this species. All of the females examined on nests in the early days 
of colony establishment were found to be fertile and all were found 
to be depositing eggs (Dirks and Hermann, 1975a). However, in 
the struggle for dominance, a significant amount of oophagy persists 
until a more stable nest is established. 
Oophagy and Cooperative Egg Deposition 
Recognition of oophagy is facilitated by the deposition of eggs near 
the cell surface after the wasp has ingested an egg. As the cells of 
a nest are elongated the eggs are deposited further and further from 
the cell base. The finding of eggs deposited a considerable distance 
from the cell base during the period of early nest building is a 
definite sign of oophagy. Oophagy will continue in an early colony 
until about the time that larvae appear. 
Each cofoundress seems to demonstrate oophagy. Likewise, in an 
early examination of reproductive systems, it was found that every 
female on a nest in the beginning stages of colony founding was 
depositing eggs (Dirks and Hermann, 1975). Hence, after oophagy 
