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was found that egg development time increased with number of 
females on the large nest and decreased on the medium nest (Table 
5). Larva development times increased with numbers of females on 
both large and medium nests. Pupa development time decreased 
with increasing numbers of females on the large nest, and did not 
change significantly on the medium nest (Table 5). 
Partial correlations of development time with date were calcu- 
lated controlling for numbers of females, since numbers of females 
increased with date. Development times of larvae increased signifi- 
cantly (p <0.01) with date on the large and medium nests when 
numbers of females were controlled for (Table 5). Development 
times of eggs decreased with increasing numbers of females on the 
medium nest when date was controlled for. Development times of 
larvae and pupae decreased with increasing numbers of females on 
the large nest when date was controlled for. 
The ratio of larvae to females on the large nest was 3. 1 1 ± S.D.2.05, 
and on the medium nest it was 1.23 ± S.D.0.47. Development time 
of larvae was slower when there were more larvae per female on the 
large nest (r = -0.13, p<0.03, N = 317). The correlation was in the 
same direction on the medium nest, but was not significant 
(r = -0.10, p >0.1, N = 296) perhaps because there averaged more 
females per larva. 
Discussion 
The results presented here do not offer strong support for the 
hypothesis that location of brood affects development rates. Cen- 
trally located brood developed no more quickly than did edge 
brood. Feeding efficiency does not appear to be limiting the size of 
nests. Foragers arriving on the nest with prey typically share it with 
3 or 4 other females who each visit many larvae (Strassmann, 
unpub.). The result seems to be even distribution of food. Though 
the largest nest did show a significant region effect for egg and larva 
development, it explained less than 7% of the variance. Perhaps an 
even larger nest would show a more marked effect. West Eberhard 
(p. 38, 1969) suggested that 7 pupae in the center of a nest she 
observed and 8 pupae towards the edge of the nest had long and 
short pupal periods respectively because of differences in larva 
nutrition. She suggested that better-fed larvae in the center of the 
nest would have longer pupa development periods. This study does 
