October, ’24] 
doane: control of cereal food insects 
551 
tests made in our laboratories with Mediterranean flour moth and 
various species of bran beetles in all stages of development: 
108° to 110° F for 1 hour killed 3-day old Mediterranean moth pupae. 
110° F for 4 hours killed about one-half of “ “ larvae. 
120° F “ 4 “ “ all stages of “ “ but did not kill all 
of the beetles. 
130° F for 4 hours killed everything. 
140° F 
170° F 
180° F 
180° F 
180° F 
180° F 
200° F 
196° F 
190° F 
It 
il 
u 
a 
u 
3 
10 
4 
4 
4 
5 
4 
5 
45 
minutes—Larvae of moths and beetles, and adult beetles in box with a 
little germea; all killed. 
“ Killed most of larvae of Mediterranean moth in shallow 
pasteboard box yi full of germea, but some still alive even 
after 3 days. 
“ Adult moths and eggs,—in open box all moths killed and no 
eggs hatched, moths not active after ly4 minutes 
“ Large and small larvae of Mediterranean moth,adult moths, 
beetle larvae and adult beetles, all put in a revolving tin 
cylinder with a small amount of germea and exposed to 180° 
F. At end of 4 minutes all seemed dead, but after 3 days 
two of the moth larvae and about of the beetles were still 
alive. 
“ Large and small larvae of moths in revolving cylinder with 
some germae,—many killed but some revived. 
“ Large and small larvae of moth in revolving cylinder with 
some germae,—all killed. 
infested box of corn meal in oven; opened 24 hours later 
and some larvae still alive. 
A badly infested package of corn meal which had been re¬ 
sealed after opening, was put in oven. A thermometer was 
put in the package so the bulb would be near center of pack¬ 
age. At end of 45 minutes the temperature of center of 
package was 120° F; about 5 minutes later, after being taken 
from oven it reached 124° F. Package opened on following 
day and all insects dead. 
Thus we see that a direct exposure to a temperature of 180°F. for 4 
minutes is fatal to all stages of the Mediterranean flour moth, but as 
soon as the insects are protected by even a very small amount of cereal 
the temperature or the time of exposure must be increased in order to 
kill all of the insects. The bran beetles are a little more resistant than 
the Mediterranean flour moth to the effects of high temperature. 
In another set of experiments in which we used eggs, larvae and adults 
of a bran beetle (Echocerus cornutus) we found that a direct exposure of 1 
minute at 181.4° F. killed all stages of the insect but when the box in 
which the beetles were held contained f/g inch of germea, an exposure of 
