2) 
That there is probable error in some of the announcements as to the 
number of broods of this insect is further evidenced in the fact that 
I have received opinions of entomologists of equally good standing in 
which they estimate the number of life cycles differently by two broods 
in the same locality. Both can not be correct. 
Again, if the eodling moth is partial-brooded in a locality, it seems 
improbable that we should find it uniformly passing the winter in the 
larval state, yet all authorities seem to agree that such is the case. 
HOW TO DETERMINE THE NUMBER OF BROODS. 
_It is not a simple problem to determine the number of broods of the 
codling moth where there are more than one. As the insect always 
winters as a larva, it must be double brooded, at least, if all the larvee 
of the first brood of worms feeding in the fruit change to the pupa 
state soon after leaving the apples. Care should be taken to obtain 
first-brood larvze, however, and if they do not change in breeding 
cages, bands should be left upon the trees for two weeks at least, and 
then the cocoons opened to see if any contain pupe. If a good num- 
ber of larvee are obtained and none transform under natural condi- 
tions, it is fair to conelude that the insect is single brooded in that — 
place. According to my experience the first-brood larvee will eon- 
tinue to appear for fully one month before those of the second brood 
will begin to arrive. 
The time occupied by the codling moth in passing through its com- 
plete round of development during the summer will average about 
seven weeks. Then if we know when the first larvee appear in the 
spring and when the latest ones cease to appear in the fall in a given 
locality, it will be a very simple mathematical computation to deter- 
mine a theoretical number of broods for the season, but it will be no 
evidence whatever that such a number exists, unless we know that all 
the eggs of a brood are deposited at one time and that all the indi- 
viduals of the brood run their course at the same rate. We know 
these conditions never occur in ease of the codling moth. The prob- 
lem we have to solve is one in which many runners are to cover a Gir- 
cular course one or more times; they run at widely varying speeds, 
and some of the earliest to start will go around once before the late 
individuals make their start. Wesuppose all are to cover the course 
the same number of times, and we are to find that number and also 
learn whether the number is the same for all. Then what must we 
know in order to determine our unknown quantities? We must know 
the beginning and the end of the period during which the insect starts 
upon its various rounds of development, and we must know the range 
of time in completing that cycle; then we must know whether those 
that complete one circuit start upon thenext. If one starts upon the 
course, it goes completely around—at least we know no exceptions to 
