30 BULLETIN 737, U. S. DEPARTMENT OF AGRICULTURE. 
In addition to the insects already mentioned the following species 
have been found frequenting cured tobacco: Trogoderma. tarsale 
Melsheimer, Attagenus piceus Olivier, Tenebrioides mauritanica 
Linnaeus, Meziwm americanum Laporte. Catorama impressifrons 
Fall and Attagenus piceus Olivier have been recorded by Morgan 
(70) as infesting tobacco seed. Meziwm americanum Laporte (Pl. 
III, fig. 3) has been found breeding in tobacco seed by Mr. S. E. 
Crumb of the Bureau of Entomology. 
NATURAL CONTROL. 
Numerous natural agencies are concerned in the control of the 
tobacco beetle. These forces, singly or combined, serve to keep the 
insect in check. 
CLIMATIC CONTROL. 
In the temperate zones, at least, the most important factor in 
holding the beetle in check is the cold of winter. Under ordinary 
conditions in cool climates their activities are confined to about. one- 
half of the year. A comparatively small proportion of the insects 
survive the winter when exposed to even moderate cold if it is long 
continued, or to sudden abnormal changes of temperature. Severe 
freezing at temperatures lower than 10° F., if continued even for a 
short time, will result in extermination. At different times in order 
to determine the effect of exposure to variations of temperature in 
unheated buildings, heavily infested cans of smoking tobacco were 
wrapped in paper and kept over winter in various localities. The 
records obtained are as follows: 
AT APPOMATOX, VA., WINTER OF 1910-11. 
About 10 pounds of pressed plug and granulated smoking to- 
bacco heavily infested were placed in original packages, in a large 
pasteboard box, wrapped with paper, and kept in an unheated 
room. A self-registering thermometer in the package showed that 
the lowest temperature reached was 11° F. Practically out-of-door 
conditions were experienced from December, 1910, until April, 1911. 
The beetles were exterminated. The tobacco was kept for several 
months but did not show signs of reinfestation. 
AT RICHMOND, VA., WINTER OF 1913-14. 
Two 5-pound packages of infested smoking tobacco were wrapped 
in paper. One package was placed in an unheated cellar, the other 
in a partly open building giving approximately out-of-door tempera- 
ture variations, Both lots of tobacco were heavily infested. The 
