The Bed-bugs 
89 
69.9 days; average number of meals 8.75 and the molts 5. Under 
conditions allowing about half the normal food supply the average 
nymphal life was from 116.9 to 139 days. Nymphs starved from 
birth lived up to 42 days. We have kept unfed nymphs, of the first 
stage, alive in a bottle for 75 days. The interesting fact was brought 
out that under these conditions of minimum food supply there were 
sometimes six molts instead of the normal number. 
The adults are remarkable for their longevity, a factor which is 
of importance in considering the spread of the insect and methods of 
control. Dufour (1833) (not De Geer, as often stated) kept speci¬ 
mens for a year, in a closed vial, without food. This ability, coupled 
with their willingness to feed upon mice, bats, and other small mam¬ 
mals, and even upon birds, accounts for the long periods that deserted 
houses and camps may remain infested. There is no evidence that 
under such conditions they are able to subsist on the starch of the 
wall paper, juices of moistened wood, or the moisture in the accumu¬ 
lations of dust, as is often stated. 
There are three or four generations a year, as Girault’s breeding 
experiments have conclusively shown. He found that the bed-bug 
does not hibernate where the conditions are such as to allow it to 
breed and that breeding is continuous unless interrupted by the lack 
of food or, during the winter, by low temperature. 
Bed-bugs ordinarily crawl from their hiding places and attack 
the face and neck or uncovered parts of the legs and arms of their 
victims. If undisturbed, they will feed to repletion. We have 
found that the young nymph would glut itself in about six minutes, 
though some individuals fed continuously for nine minutes, while 
the adult required ten to fifteen minutes for a full meal. When 
gorged, it quickly retreats to a crack or crevice to digest its meal, 
a process which requires two or three days. The effect of the bite 
depends very greatly on the susceptibility of the individual attacked. 
Some persons are so little affected that they may be wholly ignorant 
of the presence of a large number of bugs. Usually the bite produces 
a small hard swelling, or wheal, whitish in color. It may even be 
accompanied by an edema and a disagreeable inflammation, and in 
such susceptible individuals the restlessness and loss of sleep due to 
the presence of the insects may be a matter of considerable im¬ 
portance. Stiles (1907) records the case of a young man who under¬ 
went treatment for neurasthenia, the diagnosis being agreed upon by 
several prominent physicians; all symptoms promptly disappeared, 
