COCKROACHES 31 



recently in the insect-house in our Gardens, they 

 seized some leaf-insects larger than themselves and 

 devoured them alive. Within historical times, 

 chiefly by the unwilling agency of man, different 

 species of cockroach have extended their range very 

 widely, and have come into competition with each 

 other and with other insects. Is there anything 

 resembling war in that struggle for existence in 

 which cockroaches have been successful ? 



The native cockroaches of this country are small 

 creatures, less than half an inch in length. They 

 belong to the genus Ectobia, and the three or four 

 species occur also in continental Europe. The best 

 known is Ectobia lapponica, a hardy form, whose 

 range extends farthest to the north. This species is 

 said to devour the dried fish of the Laplanders and 

 probably invades their huts. But in England and 

 Europe generally the Ectobia cockroaches do not 

 come indoors except by accident. They are found 

 in the open country, in sandy heaths, under dry 

 leaves in the woods, sometimes on trees, and fre- 

 quently in that happy hunting-ground for insect 

 life, the heaps of rotting sea- weed and debris along 

 the high-water line of the shore. 



The well-known house-cockroaches, the real pests, 

 are all comparatively recent arrivals in Great Britain 

 and are all specially addicted to the neighbourhood of 

 man, never living habitually in the open, although 

 in summer they sometimes invade gardens and eat 

 buds and young shoots. The most common in this 

 country is the oriental cockroach, Periplaneta 

 orientalis, the usual domestic " blackbeetle," so- 

 called according to a humorous remark because it is 



