76 Trans. Acad. Sci. of St. Louis. 
may it be that this group is now changing from polygamy 
to monogamy, and that some characteristics belonging to 
the former habit have not yet been pruned away? 
When we go into the details of the longevity and ovi- 
position of each individual we find many exceptions to 
this hypothetical principle of longevity as an adaptation 
for the benefit of the species; some are cut short in the 
midst of reproduction, while others continue an ex- 
tended, useless life. But how do we know that this fine 
balance of longevity and oviposition ig not interrupted 
by some of the details of environment, such as climate, 
moisture, ete.? May it be that these individuals which 
do not conform to this principle of the factors of 
longevity and oviposition are merely the ones which are 
doomed to probable elimination? Natural selection may 
now be at work building up these fine adjustments; those 
which conform to this principle are those which are sur- 
viving by the cumulative effects of their complete and 
abundant reproduction, while those contrary individ- 
uals may be the straggling element, always present in 
any population, undergoing elimination by their own 
failure to oviposit adequately. 
In regard to the portion of the lifetime spent in 
copulo, it must be felt that here natural selection has not 
done refined work in having not reduced, during the 
phylogeny of the species, the time thus spent to a mini- 
mum in order to waste none of the allotted precious 
hours which the female has in which to Oviposit. 
‘In most cases we find the mated females depositing 
a greater per cent. of their eggs than the unmated indi- 
viduals, while in every population they lived a shorter 
time than their unmated sisters. This longer life of the 
unmated female in every case might suggest that Nature 
is indicating in this way that it is the species rather than 
the individual that she cares for. Still their lease of 
life was sufficient to attend to this duty in the propaga- 
tion of the species. This evidence harmonizes to a de- 
gree with Weissmann’s theory of longevity being regu- 
