Cockroaches. 



297 



and at the last change their wings are developed. In some species only the male 

 is winged, and some others are wingless in both sexes. In the kind that is onl\^ too 

 common in manv of our houses the adult male alone has wings, the female having 

 to be content with two mmute scales as evidence of the fact that she is theoreticall}^ 

 a winged Insect. The young cockroach pursues the even tenor of its way to adult 

 life in full activity, without the resting period that for many Insects precedes the 

 acquisition of wings. 



It may appear strange that though we have three native species of cockroaches, 

 neither of them can be said to be known to the public ; whilst of several foreign 

 species that have settled among us 

 without being invited two are toler- 

 ably well known, and a third perhaps 

 as well known as any British Insect. 

 This third species is the so-called 

 " black-beetle," ^ whose native land 

 has not yet been satisfactorily made 

 out. It is believed to be Asiatic, and 

 to have set about the conquest of 

 Britain three hundred years or so ago. 

 At first it was content with the occu- 

 pation of our ports, and, of course, 

 no foreign invader would overlook 

 the rich port of London. Probably 

 hiding itself away in bales of mer- 

 chandise, as later arrivals have been 

 detected in doing, it got here ; and 

 ever since it has been engaged in the 

 subjugation of the inland districts. 

 It is possible that we may owe its 

 introduction to Francis Drake, for 

 ]\Iouffet in his book on Insects, ])ub- 

 lished as early as 1634, tells how our 

 great frcebooting hero took the 

 Spanish sliij:) 7V/////), all lackii with 

 spices, and fovmd that it contained 

 also a multitude of winged cockroaches. 

 Perhaps it will he!}) the patriotic luiglislunan, who is suffering from this pest, to 

 bear his lot if he reflects that they may be the direct descendants of the winged 

 portion of that prize cargo. The reason why it is so fond of the kitchen and bake- 

 house is not merel\- that there are more chances of jucking up food there, but that 

 it comes from the tropical parts of Asia and must havc^ warmth. For this reason 

 also, it is only seen out of doors on hot summer days, wluii its migrations are effected. 

 Its spread from London to the >urrounding country appears to have been slow, 

 and this is probably due to the wingless condition of the female, which enables her 

 to go only from house to house on foot. It might spread rapidly in a town, but to 



I Stilopyga orientalis. 



Pliolo by] [II. S. Chcacin. F.R.MS. 



Spiracle of Blo\v-P"ly. 



One of the minute openings into the air-tubes, showing the system of 

 l)ranchcd hairs which protect the inlet and detain any particles of dust, 

 etc., that might caus<- blocking of the finer tubes if allowed to enter. 



