10 



of the other domestic species, has become world-wide in distribution. 

 In this country it is very often styled the Croton bug, this designation 

 coming from the fact, already alluded to, that attention was first perma- 

 nently drawn to it at the time of the completion of the Croton system 



Fig. 4. — The Oriental roach (Blatta orientalis): a, Female; 6, male; c, side view of female; d, half-grown 

 specimen. All natural size. (Original.) 



of waterworks in New York City. It had probably been introduced 

 long previously, but the extension of the w^aterworks system and of 

 piping afforded it means of ingress into residences, and greatly encour- 

 aged its spread and facilitated its multiplication. The dampness of 

 water pipes is favorable to it, and it may be carried b}^ the pressure 



F;g. 5. — The German roach {Blattdla gcrmanica): a, First stage; 6, second stage; c, third stage; d, fourth 

 stage; e, adult; /, adult female with egg-case; g, egg-case, enlarged; h, adult with wings spread. All 

 natural size except i?. (From Rilej-.) 



of the water long distances through the pipes without injury. This 

 roach has so multiplied in the eastern United States that it has now 

 become the commonest and best known of the domestic species, and 

 its injuries to food products, books, etc., and the disgusting results of 



[Cir. 51] 



