6 FARMERS’ BULLETIN 754. 
During the course of its development the bedbug molts or sheds 
its skin normally five times, and with the last molt the minute wing 
pads, characteristic of the adult insect, make their appearance. A 
period of about 11 weeks was formerly supposed to be necessary for 
the complete maturity of the insect, but breeding experiments with 
Fic. 3.—Bedbug: Egg and newly hatched larva: a, Larva from below; }, larva from above; c, claw; 
d,egg; c, hair or spine oflarva. Greatly enlarged, natural size of larva and egg indicated by hair lines. 
(Author’s illustration.) 
this insect, conducted in this department in 1896, indicated that 
the life cycle is subject to great variation, being entirely dependent 
on warmth and food supply. Under favorable conditions of temper- 
ature and food it was found that there was an average period of about 
eight days between moltings and between the laying of eggs and 
their hatching, giving about seven weeks as the period under these 
fic. 4.—Bedbug: a, Larval skin shed at first molt; b, second larval stage immediately after emerging from 
a; c, same after first meal, distended with blood. Greatly enlarged. (Author’s illustration.) 
conditions from egg to adult insect. The molting periods are shorter 
in the earlier stages and lengthen in the later stages. There are many 
exceptions, however, and some individuals even under the same 
conditions remain two or three weeks without molting. Under con- 
ditions of famine, or without food, as already shown, the bedbug may 
remain unchanged in any of the immature stages for an indefinite 
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