RELATION TO THE HOUSEHOLD 229 



about the same time. As a matter of policy it is always 

 well to begin a roach campaign before the egg cases 

 have been fully developed, as there are then much 

 fewer specimens to be dealt with. 



The Hemiptera as an order are always difficult to 

 place in a linear series among the mandibulata, but 

 they contain one species that must be referred to among 

 the forms dwelling with man the "bed-bug," Cimex 

 lectularius . It has local names in different parts of the 



FIG. 107. The bed-bug from above and below and egg. 



country, but "bed-bugs" are always recognized even 

 where they are commonly referred to as "chinches." 

 There are quite a number of the Hemiptera that are very 

 much flattened and fitted to live in narrow crevices; 

 but none more than this bed-bug which occurs now-a- 

 days only in connection with human habitations. An 

 allied species lives in the nests of swallows, sometimes 

 in great numbers, but does not infest houses. 



The pest is found all over the world and has been 

 recorded ever since there were any records; so there is 

 an immense fund of information concerning it some 

 true, some more or less imaginary, like the tales of the 



