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JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. 16 
is exposed from the calyx; (3) two weeks after the second; and (4) four weeks before 
each variety is due to ripen. Four applications of lead is too much as an annual 
treatment for peach trees in the South. The four application schedule should be 
used when the curcuho infestation is heavy, otherwise the lead in the third application 
should be omitted. 
The severe outbreak of the plum curculio in the peach belt of Georgia 
during the season of 1920, which resulted in a loss of over two million 
dollars to the peach growers of that district, brought about the establish¬ 
ment of the Peach Pest Laboratory at Fort Valley, Georgia, and the 
inauguration of extensive investigations dealing with the life history 
and control of the insect. During the two years that this work has 
been under way some very important discoveries have been made in the 
life history of the pest, and a great amount of valuable data has been 
obtained on control measures. In order to make this paper as brief 
as possible it is my intention to develop only the most important re¬ 
sults of this work, and to touch on the data that will be of most value to 
those working with the problem in other states. 
The most important truth revealed as a result of these studies was the 
establishment as a scientific fact that in the latitude of Central Georgia 
there occurs annually two generations of the plum curculio, and that a 
high precentage of the larvae that renders the best late varieties of 
peaches unmerchantable in Georgia are larvae of the second generation. 
Furthermore, during the past season, I was successful in carrying through 
three generations, under normal conditions, at Fort Valley. The first 
adult of the third generation left the soil on October 7, the larva having 
left the fruit and entered the soil on September 11. Cool weather had 
set in before any of the third generation adults emerged, and a few 
days after their appearance from the soil they went into hibernation 
without the deposition of any eggs, or without showing any signs of 
copulation. Of course the third generation of the plum curculio is of 
very little importance in Georgia since the peach season is normally over 
there by August 1. The third generation was reared in the insectary in 
peach; late peaches being supplied, a few of which are grown by several 
growers in Central Georgia. These important discoveries, during the 
last two years, in the life history of an insect that has been referred to for 
nearly two centuries, and about which perhaps more has been written 
than any other American insect, are good illustrations of the probability 
that we still have a good many things to find out about even our best 
known insects. These interesting discoveries also indicate that the 
plum curculio should again be thoroughly studied throughout its range 
