LIFE HISTORY OF BEDBUGS 375 



of different species from the human pests, and are not known to 

 annoy man voluntarily, although they occasionally enter rooms 

 from the nests of chimney swifts. Bats are often accused of 

 carrying bedbugs into houses, but they, too, are attended by 

 their own particular species which does not attack man. The 

 assertion that bedbugs can be found under bark and moss out 

 of doors also arises from a misapprehension. These bugs are 

 really the immature stages of certain other species of bugs which 

 resemble bedbugs closely enough to be mistaken for them by a 

 casual observer. 



Although human blood is their normal food, bedbugs are able 

 to subsist on the blood of such animals as rats, mice, rabbits, 

 cats, dogs and even chickens. It has also been shown that bugs 

 will suck blood from freshly killed mice. By utilizing mice 

 and rats as a food supply they are able to exist in deserted build- 

 ings for a long time. Furthermore they are able to endure long 

 fasts; they have been kept alive without any food whatever for 

 a year. Murray has found that bugs which have been starved 

 even for a long time pass unaltered blood corpuscles in their 

 faeces, and suggests that a small quantity of food may be re- 

 tained undigested in the rectum to be drawn upon very slowly in 

 time of need, though when a fresh supply of blood is obtained 

 the old store is cleared out. Bugs also store up a great deal of 

 fat for use in time of famine. Sometimes, however, after a house 

 has been deserted for some time, and their normal supply of 

 food is cut off, the bugs migrate in search of an inhabited house. 

 In cold weather bugs hibernate in a semi-torpid condition and 

 do not feed, but in warm climates they are active the year around. 

 The common bedbug, according to Marlatt, is sensitive to 

 temperatures of 96 F. to 100 F. or more if accompanied by a 

 high degree of humidity, and is killed in large numbers under such 

 climatic conditions. According to Bacot, unfed newly hatched 

 bugs are able to withstand cold between 28 F. and 32 F. for 

 as much as 18 days, though they are destroyed by exposure to 

 damp cold after a full meal. 



Life History. The eggs of bedbugs (Fig. 167A) are pearly 

 white oval objects, furnished with a little cap at one end which 

 is bent to one side. As in the case of lice, the eggs are relatively 

 large, being about one mm. (^V of an inch) in length, and are 

 therefore laid singly or in small batches. The ovaries hold about 



