THE BEDBUG. 9 
temperatures .below this point. The most favorable temperatures 
for activity are between 60° and 98° F.t. The activity of the insect 
is controlled entirely by temperature and food supply, and, there- 
fore, in heated houses the insect may remain active throughout the 
winter. There is some protection in winter, therefore, in sleeping in 
cold bedrooms. 
THE BITE OF THE BEDBUG. 
The bite of the bedbug is decidedly poisonous to some individuals, 
resulting in a slight swelling and disagreeable inflammation. To such 
persons the presence of bedbugs is sufficient to cause the greatest 
uneasiness, if not to put sleep and rest entirely out of the question. 
With others, however, who are less sensitive, the presence of the bugs 
may not be recogriized at all, and, except for the occasional staining 
of the linen by a crushed individual, their presence might be entirely 
overlooked. The inflammation experienced by sensitive persons 
seems to result chiefly from the puncture of the skin by the sharp 
piercing setz which constitute the puncturing element of the mouth 
parts, as there seems to be no secretion of poison other than the 
natural fluids of the mouth. 
The biting organ of the bedbug is similar to that of other insects of 
its order. It consists of a rather heavy, fleshy under lip (the only 
part ordinarily seen in examining the insect), within which lie four 
threadlike hard filaments or sete: which glide over one another with 
an alternating motion and pierce the flesh. The blood is drawn up 
through the beak, which is closely appled to the point of puncture, 
and the alternating motion of the setz in the flesh causes the blood 
to flow more freely. The details of the structure of the beak are 
shown in figure 1 at d. 
To allay the irritation set up by the bite of the bedbug, peroxide 
of hydrogen, or dioxygen, may be used with good results. 
Tincture of iodine either at ordinary or double strength is also a 
good counter-irritant for use in cases of flea, mosquito, bedbug, and 
other insect bites, but should be used with caution on the tender 
skin of small children and on those who are affected with or disposed 
to eczemic disorders. 
THE BEDBUG AND HUMAN DISEASES. 
In .common with other insects which attack man and warm- 
blooded animals, it is entirely possible for the bedbug and its close 
allies to be transmitters of contagious human diseases, and already 
these insects have been shown to be possible carriers or transmitters 
of a considerable series of diseases, including infantile Kala-azar of 
northern Africa and southern Europe, relapsing fever of Africa and 
Europe, the Chagas fever of Brazil, tropical sore, plague, and possibly 
1 Bacot, A. W. The influence of temperature, submersion, and burial on the survival of eggs and larve 
of Cimez lectularius. In Bul. Ent. Res., v. 5, pt. 2, p. 111-117. 1914. 
