156 
Psyche 
[September 
the cell was easily audible at a distance of i m from the nest. Pos- 
sibly this behavior alerted the larvae to the food offering. After 
feeding 2 or 3 larvae, the forager usually groomed briefly and then 
took off. The entire exchange sometimes took as little as 2 minutes. 
When a third wasp was present on the nest, it sometimes tried to 
steal food during the exchange. In one case, when the third wasp 
managed to obtain a large amount of nectar, the exchange ended 
with the donor biting the intruder. 
As the queen moved about the nest, she often dragged her ab- 
domen across the face of the nest, and moved it slightly from side 
to side in the process. Other wasps showed the same behavior but 
less consistently. The queen and the second ranking female both 
showed a peculiar behavior of rubbing their abdomens over the 
pedicel of the nest; the queen twice and the second ranking female 
4 times. A similar behavior was reported by Jeanne (1970) in 
Mischocyttarus drewseni. He showed that wasps in that species 
were depositing a substance which is repellent to ants. 
On only one occasion was the queen observed eating an egg. The 
process took about 3 minutes. She did not lay another egg in the 
cell. In fact, I did not see any of the wasps ovipositing during all 
of my observations, though nest records show that they must have 
laid at least 4 eggs during the 17 days. At the end of the observa- 
tion period, the queen was dissected and found to contain 4 ripe 
eggs and a full spermatheca. 
Conclusion 
The behavioral repertoire of this wasp is very similar to that of 
P. canadensis as reported by Eberhard (1969). The size and gen- 
tleness of this wasp make it very suitable for behavioral observa- 
tions. The association of P. carnifex with other social wasps has 
not been reported outside of 'Costa Rica. Data on the nesting suc- 
cess in associated and non-associated nests are needed to determine 
what advantage, if any, Polistes carnifex receives or confers in this 
association. 
Acknowledgements 
Part of this study was a held project in the Tropical Ecology 
course (1971) of the Organization for Tropical Studies. I am 
grateful to Peter Becker, Valerie Dryer, Doug Gill, Julie Multer, 
and A 1 Muth, who made heroic efforts collecting the nests in Costa 
