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PUPAL PERIOD 
Pupe of the first generation were present from about the middle of 
June to the middle of August and the period varied from 8 to 14 days, 
the average being 10.6 days. Pupz of the second generation were pres- 
ent during August and the first part of September. The period varied 
from 9 to 18 days, the average being 12.1 days. None of the third-genera- 
tion larvee pupated. The pupal period of this generation is therefore dis- 
cussed in connection with the hibernating generation. 
Pupe of the hibernating generation were present during April, May, 
and the first part of June. The period varied from 39 days to 18 days, 
the average being 30.9 days. The average pupal period of the males 
and the females is practically the same. The period of the hibernating 
generation is much longer than that of the other generations because 
pupz are present during early spring when the weather is cool. 
COMBINED EGG, LARVAL, AND PUPAL PERIODS 
The whole period of development is of the greatest importance since 
it is an index to the time which elapses from the deposition of the egg 
to the emergence of the adult. Since the deposition of eggs frequently 
begins within one day after the emergence of the female, the addition of 
one day to the period of development will give the time which elapses 
from the deposition of the egg of one generation to the deposition of 
the first egg of the following generation. For 103 males of the first 
generation the period varied from 40 to 59 days, the average being 51.1 
days; for 131 females, the period varied from 43 to 62 days, the average 
being 52.4 days. For both males and females the average was 51.8 days. 
The period of development for the individuals which hatch first in 
the spring is much longer than for those which hatch later, the minimum 
period for those hatching earliest being 50 days. We may expect, there- 
fore, the deposition of the first eggs of the second generation to follow 
the deposition of the first eggs of the first generation in an average of 
about 51 days, though the average for this same period for the entire 
generation is only about 53 days. The above applies to individuals 
whose larval period was passed in apples on the tree. The period would 
be about 4 or 5 days shorter for those whose larve fed on picked apples. 
The development period of 41 transforming males of the second 
generation varied from 38 to 50 days, the average being 43.7 days, and 
of 62 females from 33 to 56 days, the average being 45.4 days, the aver- 
age for males and females being 44.7 days. The minimum period for 
the first individuals of the second generation was 37 days. We may, 
therefore, expect the deposition of eggs of the third generation to begin 
about 38 days after the deposition of the first eggs of the second 
generation. 
The period from the first eggs of one generation to the first eggs of 
the next will vary with the season. The time which elapsed between 
