and dependent upon so many factors that it is difficult to make any 
generalizations regarding it, but from the many observations made 
we have drawn the following conclusions: Under the conditions for 
the last two years at College Station the critical period in the relation 
between the natural increase of squares and the increase of injury by 
the weevil is during the first six to eight weeks after squaring com- 
mences, which usually coincides more or less closely with the time 
between the second and third broods of weevils. Therefore, if we 
consider. six weeks as the average time for cotton to square after 
planting, the bulk of the bolls must be set between eighty-five and 
ninety days after the time of planting. In other words, to escape 
injury by the weevil cotton must be grown so that the first bolls will 
commence to open about one hundred days after planting, and that all 
the fruit which will probably be secured must be set forty-five days 
after the squares form. The advantages of early varieties, other 
things being equal, is therefore apparent. ; 
But should the weevil increase more rapidly than observed we 
would have injury even though the cotton were early. The rate of 
increase of the weevil is therefore most important. Irom the studies 
of Hunter and Hinds we learn that a female normally lays about 150 
eggs in about fifty-four days (average figures), and that nearly half 
are deposited during the first third of the period. Allowing twenty- 
four days for development, they estimate the total normal period for 
a generation to be forty-two days. By counts of thousands of squares 
at different seasons we have determined the average rate of mortality 
of weevils in squares to be about 65 per cent. The sexes are prac- 
tically equal in numbers. . With these facts it is easy to compute that 
if there be 2 weevils per 100 stalks on June 1—about the number at 
College Station—on the appearance of the second brood in mid-July 
there would be 50 weevils, and these would produce by September 1 
1.250 adults. In other words, the second brood would be twenty-five 
times and the third six hundred and twenty-five times the number of 
the first. But although we have three broods in the field during this 
time the increase is by no means so great. Were it so no cotton could 
be raised. The increase of the second brood over the hibernated 
brood is considerably less than twenty-five times, usually not over 
fifteen times, and the total increase from June 1 to September 1 is 
only about fifty times—certainly not over sixty-five times—instead ~ 
of six hundred and twenty-five times, as it should be theoretically. 
The reason for this discrepancy is unknown to the writer, but for it 
the planter may be exceedingiy thankful. It may be that (1) the 
mortality of the immature stages is greater than determined, which 
we decidedly doubt: (2) many of the adult weevils die or are de- 
stroyed before reproducing; or (3) the number of eggs laid and the 
length of period of oviposition actually occurring in the field are 
