THE HEMIPTERA 



183 



only tiny stubs of wings remaining to show that it has been derived 

 from winged ancestors. It produces a very noticeable odor. 



It is a nocturnal animal, hiding during the day in any cracks and 

 crevices it may find, either in the bedstead, behind loose wall paper or 

 elsewhere. In these places it lays its eggs, probal)ly about 200 in num- 

 ber, these hatching in from a week to a much longer period dependent 

 upon the temperature. The nymphs are yellowish-white at first, turning 

 brown gradually with increasing age. Nymphal life varies greatly in its 

 length, being affected by the temperature 

 and food supply, but when these are favor- 

 able, about 7 weeks is required to produce the 

 adult bug. Under less favoring circumstances 

 the nymphs may remain unchanged but ahve, 

 for a long period. The number of genera- 

 tions in a year may therefore differ greatly 

 under different conditions but in warmed 

 houses there are probably at least four. 



Where human blood is not obtainable for 

 food, that of mice, rats or other animals 

 where available, may be taken instead, and 

 hving bedbugs in empty houses may perhaps 

 be accounted for in this way. Without food, 

 however, death within a year is a practical 

 certainty. 



The "bite" of the bedbug is quite poison- 

 ous to some persons l)ut not to others and in 



some cases a sort of immunity is obtained by individuals continuously 

 exposed to attacks. 



Bedbugs are known to be carriers of contagious diseases of man, such 

 as the African relapsing, fever, Kala-azar, plague, and possibly leprosy 

 also, but of course the insect must first become itself infected with the 

 causal agent of the disease which is very rarely the case, at least in 

 the United States. It does not appear to transmit the diseases except 

 as the agents of them by accident get on the mouth parts of the insect. 

 Control. — Where sulfur can be burned in a room, using a pound for 

 each 1,000 cu. ft. of space for 24 hr. the fumes will destroy all stages of the 

 l^edbug if the room is reasonably tight. A thorough treatment of all places 

 where the insects can hide and lay their eggs, with gasoline, benzine or 

 kerosene is also successful if the material penetrates all parts of the cracks. 

 Corrosive sublimate at least as strong as a 6 per cent water solution, can 

 be used in the same way. Heating a room or house to from 120 to 130°F. 

 in summer for an hour or even less has proved effective, as has a tempera- 

 ture below 32°F. continued for 3 or 4 weeks. Persons obliged to stop at 

 infested places can usually obtain protection by dusting insect powder 

 (Pyrethrum) between the sheets of the bed. 



Fig. 172. — Adult female 

 Bedbug {Cimex lectularius L.) 

 gorged with blood. Greatly 

 enlarged. {From U. S. D. A. 

 Farm. Bull. 754.) 



