104 
INCREASE IN NUMBERS DURING THE SEASON. 
The comparative difference in numbers between the moths of the 
tirst and second generations can be determined in a general wa}" from 
the tables on oviposition already given, since corn receives practically 
all the eggs of these generations. It is seen that the second genera- 
tion la3\s about forty times as man}" eggs as the first, and assuming, 
as seems to be the case, that these moths la}^ individually many more 
than the spring moths, it ma}^ be said that for every spring moth 
there are thirt}" moths in the second generation. This agrees well 
with observations made in the field. 
Fifteen, or one-half of these moths being females, lay pj'obabh^ about 
1,100 eggs each. Of these onl}^ about one larva in fifteen matures, or 
about fifteen times as man}" as there were moths in the second gener- 
ation. This number is about 1,100. 
Half of these, emerging as female moths of the next generation, will 
lay in all some 605,000 eggs. Observations show that about one in ten 
of these eggs, or 60,500, will give rise to destructive larvte. 
Allowing for the probable decimation of 65 per cent by the para- 
sites and predaceous enemies of the growing bollworms, there still 
remain some 21,175 larvse of the third generation to mature on cotton 
for every moth emerging the previous spring. 
This shows the great importance of destroying the larvae of the first 
generation, as every one of them will average 683 descendants in the 
late summer capable of completely ruining 78 large cotton plants. 
DO THE ADULTS HIBERNATE? 
The hibernation of the adult bollworm moth has always been an 
open question, and in order to obtain all possible data bearing evi- 
dence on this point, Mr. Girault made a trip into southern Texas dur- 
ing the early part of February, 1901, with the especial purpose of 
searching for hibernating individuals. 
At Corpus Christi and Victoria a number of days were spent in 
examining places where hibernating- moths would be apt to hide. 
These included w^oodlands surrounding fields, rubbish in corn and 
cotton fields, barns, outhouses, etc., but not a single bollworm moth 
was discovered. Fresh growing plants and garden vegetables were 
searched also and sugaring tried, but with the same result. 
Mr. J. D. Mitchell, of Victoria, believed that he had frequently seen 
hibernating specimens, but in two cases at least it was found that he 
had been misled by the close resemblance in color and general appear- 
ance of Helhpkila {Leuccmia) unipivncta Haw. and Bemigia repanda 
Fab., to the bollworm moth. 
All laboratory experiments bearing on this point, also tend to show 
that while life may be prolonged by subjection to low temperatures, no 
