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good condition. All were active the following day, August 5, at 
7 o’clock a. m. Observations were taken, as before, every four 
hours during the day. At 7 p. m. an adult which had emerged 
was in good condition, but two pupae were on their backs, appar¬ 
ently unable to turn over. Two more adults had emerged the fol¬ 
lowing mornirg, August 6, and were actively swimming about the 
surface of the water, endeavoring to escape. At 10 a. m. two 
pupae were noticed on their backs, and when turned over were 
soon on their backs again, and an hour later they had sunk to 
the bottom. The adult that emerged August 5 was dead at this 
time and was removed. It was plainly visible that tbe pupae were 
weakening. Two more were dead at 2 p. m. and three more at 6 
o’clock, leaving only eight alive, and four of these were dead and 
had sunk to the bottom the following morning (August 7) at 7 
o’clock. The other four remained alive until 11 a. m., when all 
were dead and three of them in the bottom of the tumbler. From 
this it appears that the average life of pupae on the surface of 
water is about three and three fourths days. 
No. 5. Eighteen recently molted adults were selected and floated 
on water on the same day and at the same time as those in 
No. 4. These bugs, however, were separated into six lots of three 
each. They were very active when first floated, and three escaped 
during the night. Those remaining swam freely about the surface 
of the water August 4, but no more escaped. One, however, had 
gotten on its back, and when removed at 6 p. m. was about dead. 
It was removed for a few moments and then replaced, but it was 
dead the following morning, August 5, when, however, the others 
were in good condition. These were alive and apparently healthy 
August 6, and no change was noted the following day. One was 
found on its back August 8, at 10 a. m, but revived and lived 
until August 11, 8 a. m. The remaining thirteen insects seemed 
in good condition August 12, and were alive on the 14th. On the 
15th one was noticed to be weakening, but it did not die until the 
18th, at which time six more were dead, two of them having sunk 
to the bottom. The following day, August 19, the others died and 
were removed. It appears from this experiment that adult chinch- 
bugs (generation not definitely known) can live on the surface of 
water about fifteen days, the average for the lot, however, being 
about thirteen days. 
CONFINEMENT EXPERIMENT. 
I report here a series of three confinement experiments with 
chinch-bugs of various ages. They were collected from the same 
field as those used in the foregoing experiments. From No. 1 it 
appears that adult chinch-bugs in close confinement in a dry vial 
are less hardy than the young, the adults in this case having 
lived only seven days, while the other stages lived eight and nine 
days. There is some doubt, however, about the age of the adults 
used in this experiment. They were selected with care, and only 
those with bright fresh wings were used, but even these may have 
been several weeks old, and possibly partially spent males and 
