THE TOBACCO BEETLE. ° 27 
In the laboratory at Clarksville, Tenn., beetles were kept under 
observation continuously by Mr. 8. E. Crumb during 1910-11. 
The rearing material was kept in a room heated only during the 
day during winter. Larve which constructed pupal cells in No- 
vember, 1910, became adults May 18, 1911. These beetles deposited 
eggs about May 31, from which adults were obtained about July 29. 
These beetles deposited eggs August 138, from which adults were 
obtained on September 28. Eggs were obtained from these adults 
October 5. Larvee from this lot of eggs constructed cells in which 
they passed the winter of 1911-12. This gives for the locality three 
distinct generations, emerging in the adult stage in May, July, and 
September. In localities farther south from three to six generations 
may occur, since under laboratory conditions at normal summer tem- 
peratures the entire life cycle was found to average 60 days. 
At Richmond, Va., it was determined that three generations may 
occur under warehouse conditions. On October 14, 1913, eggs were 
placed in tobacco, and larvee were found in cells in a dormant con- 
dition during December, which transformed the following spring. 
Adults collected from the lot May 5, 1914, deposited eggs on May 
6-7. Adults reared from these eggs were obtained July 22, and 
eggs were laid about July 25. From these eggs adults were again 
obtained about October 2. Eggs deposited by beetles from this 
lot hatched October 18, the larvee becoming dormant during the 
latter part of November. This shows that for this locality there 
are three complete life cycles, the adults appearing in May, July, 
and October, and that from the adults which emerge earliest there 
is a possibility of a fourth generation reaching the adult stage 
before winter. 
In the Middle and Northern States, in warehouses and tobacco 
factories, a sudden appearance of large numbers of adults in spring 
or early summer is frequently observed. The greater number of 
larvee which survive the winter complete their transformation and 
emerge in the adult stage with the advent of warm weather. 
INSECTS LIKELY TO BE MISTAKEN FOR THE TOBACCO BEETLE. 
Belief still prevails in many sections that the tobacco’ beetle is found 
on growing tobacco and that it continues to feed upon the tobacco 
after it has been cured. This impression is due perhaps to its slight 
resemblance to a smaller and very common insect, the tobacco flea- 
beetle (L'pitrix parvula Fabricius) (fig. 8), which is abundant on 
growing tobacco in the field and in tobacco plant beds. Contrary to 
this belief the tobacco beetle (Lasioderma serricorne) does not attack 
growing tobacco and is not present in tobacco fields. It is not a field 
msect, but feeds and lives in dried substances, its more common food 
being cured:tobacco. The habit of the tobacco flea-beetle of hopping 
when disturbed, its occurrence on growing tobacco, its smaller size, 
