8 FARMERS’ BULLETIN 1754. 
series of experiments was later conducted by Girault,’ bearing on the 
longevity of the insect under different conditions. A large number 
of adults of both sexes were kept in confinement, but with normal 
feeding and mating, and these survived for periods ranging from 54 
to 316 days. Similarly, the life of 71 newly hatched larve, without 
food, ranged from 17 to 42 days, averaging about 28 days. Partly 
grown captured insects lived without further feeding from 17 to 60 
days. Longevity is naturally affected more or less by temperatures. 
In other words, temperatures sufficient to check the activity of the 
insect and produce hibernation or semihibernation are apt to increase 
longevity. 
The fact that the bedbug is able to survive for such long periods 
without human blood has led to the theory that it could subsist in 
some fashion on the moisture from wood or from accumulations of 
dust in crevices in flooring, etc. There seems to be no basis of 
observed fact for this idea. 
Another very prevalent belief among the old settlers in the West, 
that this insect normally lives on dead or diseased cottonwood logs, 
and is almost certain to abound in log houses of this wood, seems to 
be equally devoid of basis. As illustrating this belief, the depart- 
ment has on file a very definite report from an Army officer that the 
bedbug often occurs in numbers under the bark of dead cottonwood 
trees,’ especially along the Big Horn and Little Horn Rivers in 
Montana. The basis of this report and the origin of this very general 
misconception is probably, as pointed out by the late Prof. Riley, 
due to a confusion of the bedbug with the immature stages of an 
entirely distinct insect,*? which somewhat resembles the bedbug and 
often occurs under cottonwood bark. 
INFLUENCE OF TEMPERATURE. 
As a messmate of human beings in dwelling houses, the bedbug is 
normally protected from extreme cold, and is known to be an 
abundant and serious pest far north. In fact, it is often more 
troublesome in north temperate latitudes than farther south. This 
may be accounted for partly by the fact that the bedbug is very 
sensitive to high temperatures, and a temperature of 96° to 100° F. 
or more, accompanied with a fairly high degree of humidity, results 
in the death of large numbers of the bugs. The mature or partly 
mature bedbugs can stand comparatively low temperatures, even 
below freezing, for a considerable period. The eggs and newly 
hatched larve, however, succumb to a temperature below freezing, 
if this condition is prolonged for from 15 days to a month: The 
feeding and developing activity of the insect practically ceases at 
60° F., the insect remaining quiescent and in semihibernation at 
1Loc. cit. 2 Populus monilifera. 3 Aradus sp. 
