31 
i 
I have dissected a great many fully matured females, some im¬ 
mediately after pairing and others just before, but have not ob¬ 
tained any such results as those tabulated by Professor Landois. The 
greatest number of eggs I have obtained by dissection is 342, and 
the least number 187. I have also carefully examiLed a series of 
females after death, immediately after the eggs had been deposited, 
to see if any undeveloped eggs were left in the ovaries, and in 
five cases found they were completely spent, while I found seven 
eggs each in three others, fourteen in another, and twenty-six in 
another. This would seem to indicate that the total number of 
eggs in the ovaries does not represent in all cases the total num¬ 
ber that may be laid by a single individual. As stated above, 
the greatest number of eggs I have yet obtained from a single 
female is 271 (No. 3), and an examination of the parent insect 
later showed that the ovaries were spent. 
A correspondent of mine in California was asked by me to con¬ 
duct a series of experiments in his mill during the month of 
November, 1892, to ascertain the exact time required for the in¬ 
cubation of the flour-moth eggs, and on December 5 I received 
the following reply: “The eggs hatch in my mill, under the most 
favorable conditions, in a trifle less than nine days.” This is in 
accordance with my own experiments. Mr. James Fletcher says 
that caterpillars emerged in December, in a warm office, about 
nineteen days after the eggs were laid. I cannot account for this 
difference in time, as eggs deposited December 4, 1894, kept in 
my office where the temperature ranged from 38 J to 72 Fah. 
hatched in exactly nine days. As has been shown by Mr. Danysz 
the development of the embryo is greatly retarded by a continuous 
low temperature, and it is possible that the eggs in Mr. Fletcher s 
office may have been exposed to a lower temperature than 38 Fah. 
for a considerable length of time, which would, possibly, explain 
the difference in the period of development. Another point to be 
taken into consideration is the fact, that the female is from five 
to six days in depositing her eggs, and that there is a difference 
of as many days in the hatching of the first-laid and the last-laid 
eggs of the same generation. 
The active or feeding stage of the larva depends upon the tem¬ 
perature of its surroundings, and upon the kind and amount of food. 
Larvae hatched from eggs October 9, 1894, were divided into two 
lots and placed in breeding-cages with wheat flour for food. One 
cage was placed in the insectary where the temperature varied 
from 28° to 78° Fah., and the other was kept in a warm office at a 
temperature of 48 to 82 Fah. Larvae in the former lot were 
fully matured November 26, or in about seven weeks, and in the 
latter November 13, or just five weeks from the time they emerged 
from the eggs. In other experiments conducted to test the effect 
of the amount and kind of food on the larvae, I have had varied 
results. Larvae feeding on coarse corn meal, for example, did not 
mature as quickly as those in the same room fed on wheat or 
buckwheat flour. As already stated the average active period of 
-the larva is about forty days; but under the most favorable cir- 
