38 BULLETIN 1313, U. S. DEPARTMENT OF AGRICULTURE 
With the exception of four cars fumigated for milling and baking 
tests, the rice weevil (S. oryza) was the test insect used in the pill boxes. 
Furthermore, the grain in all but two of the cars was moderately 
infested with weevils. The results given in the last column in 
Table 14 show the percentage kill of this natural infestation. 
The results of the car fumigation reported in Table 14 confirm those 
reported in Table 8. 
With the exception of one case, where fumigation was inter- 
rupted, all fumigations with a mixture of 40 per cent by volume of ethyl 
acetate and 60 per cent by volume of carbon tetrachloride, in which 
not less than 40 pounds of the mixture per 1,000 cubic feet of inclosed 
space was used, gave satisfactory kills. 
The results of the milling tests with the wheat fumigated in these 
box-car experiments are shown in Table 15; the results of the baking 
tests with flour made from this wheat are shown in Table 16. The 
data indicate that both the fiavor and odor of bread baked from flour 
made from wheat fumigated in box cars with a mixture of 40 volumes 
of ethyl acetate and 60 volumes of carbon tetrachloride, at the rate of 
40 pounds per 1,000 cubic feet, are normal. 
EFFECT OF ETHYL ACETATE-CARBON TETRACHLORIDE 
FUMIGATION ON GERMINATION OF SEEDS 
The seeds of wheat, barley, rye, winter oats, and corn in _ tightly 
closed bell jars were exposed to the vapor of ethyl acetate and carbon 
tetrachloride at a concentration of 40 pounds per 1,000 cubic feet 
for 24 hours. The percentage germination before and after fumiga- 
tion is shown in Table 17. 
TABLE 17.—Effect of ethyl acetate-carbon tetrachloride fumigation on germination 
of seeds 
Germination | Germination 
Seed Before | After | Seed | Before | After 
fumiga- | fumiga- 
tion tion 
et 
© 
i} 
ipl 
oO 5 
is) 
Per cent | Per cent 
3 a5 
WW hieak =<} se ee 2 ee § Winter oats: =.= -2 es ee 
Rariey = Ee O7 OR) QO or 2 ee 
SE yee tee ee a ee eee 89 | 
The results in Table 17 show that exposure at 31° C. in a tight 
container for 24 hours to the fumes of a 40-60 mixture (by volume) 
of ethyl acetate and carbon tetrachloride at the rate of 40 pounds 
per 1,000 cubic feet does not injure the germinating power of wheat, 
barley, rye, winter oats, and corn. The grain would not be subjected 
to as severe a test in ordinary box cars. 
SUMMARY 
The action of more than 100 organic compounds on weevils was 
tested under conditions permitting a control of the factors of con- 
centration, time, and humidity, and with observations of the tem- 
perature. 
The following 30 compounds were more toxic to the rice weevil 
(S. oryza L.) than carbon disulphide: Two out of 8 bromides tested; 
