THE TOBACCO BEETLE. 31 
exposure extended from November, 1918, until March, 1914. A self- 
registering thermometer in the open building showed the lowest tem- 
perature to be 12° F., and this temperature was reached several times 
during the winter. The lowest point reached in the cellar was not 
determined, but the protection afforded gave somewhat higher tem- 
peratures than obtained in the open building. On examination in 
March a very few live larve were found in the tobacco kept in the 
cellar. The tobacco in the open building was completely sterilized. 
The package was sealed and kept under observation until June, 1914, 
but no live stages of the beetles were found. 
AT OAK HARBOR, OHIO, WINTER OF 1914-15. 
A package prepared at Richmond, Va., contained about 5 pounds 
of heavily infested smoking tobacco, part pressed or sliced plug and 
the rest granulated, and a package of infested cigars and cigarettes. 
About 1,000 eggs of the tobacco beetle had been placed in the smoking 
tobacco November 1, 1914. This was mailed on November 14 to Oak 
Harbor, Ohio, where it was placed in an unheated building on No- 
vember 17. It was examined June 10, 1915. No live stages of the 
beetle were found. The lowest temperature registered in the building 
was 10° F. 
AT CLARKSVILLE, TENN., WINTER OF 1915-16. 
About 10 pounds of smoking tobacco wrapped in paper were kept 
over winter in an unheated room in the laboratory. The tobacco con- 
tained all stages of the beetle. On November 1, 1915, about 1,000 
eggs of the beetle were placed in the tobacco. These eggs hatched 
about November 10. No record was secured of the lowest tempera- 
ture in the room. The lowest record out of doors was 5° F. The 
tobacco was examined during April, 1916. No live stages of the 
beetle were found. Although the tobacco was kept under observa- 
tion for several months no signs of infestation were observed. 
Evidence of the effect of freezing on the tobacco beetle has been 
observed on numerous occasions and it is not uncommon to find leaf 
tobacco or other food substances which have been exposed to low 
temperatures completely free from the beetle although its condition 
showed that it had been heavily infested previously. It has been the 
experience of those familiar with the tobacco industry that beetles 
always become more abundant and destructive after a mild winter. 
DRYING OUT OF FOOD SUBSTANCES. 
The tobacco beetle thrives best in tobacco that is protected from 
‘Tapid evaporation and when the humidity is high. If the tobacco 
remains very dry for a considcrable length of time the rate of multi- 
