ix HABITS OF COCKROACHES 231 



We may take this opportunity of alluding to the attraction 

 that light exerts on Insects. Many species that conceal them- 

 selves during the daytime and shun light as if it were dis- 

 agreeable, are at night-time so fascinated by it that it is the 

 cause of their destruction. The quantity of Insects killed in this 

 way by electric and other bright lights is now enormous ; in 

 many species the individuals immolate themselves by myriads. 

 It would appear that only nocturnal and winged species are so 

 attracted. So far as we know, light has no fascination for Insects 

 except when they are on the wing. The phenomenon is not 

 understood at present. 



The food of Blattidae is believed to be of a very mixed 

 character, though Brunner considers that dead animal matter is 

 the natural nutriment of the members of this family. It is well 

 known that the common cockroach eats a variety of peculiar 

 substances ; its individuals undoubtedly have the somewhat too 

 economical habit of eating their own cast skins and empty egg- 

 capsules, but in this they only act like many other much admired 

 Insects. S. orientalis is gregarious, and the individuals are 

 very amicable with one another ; small specimens sit on, or run 

 over the big individuals, and even nestle under them without their 

 displaying the least resentment. The common cockroach is a 

 rather amusing pet, as the creatures occasionally assume most 

 comical attitudes, especially when cleaning their limbs ; this they 

 do somewhat after the fashion of cats, extending the head as far 

 as they can in the desired direction, and then passing a leg or 

 antenna through the mouth ; or they comb other parts of the 

 body with the spines on the legs, sometimes twisting and distort- 

 ing themselves considerably in order to reach some not very 

 accessible part of the body. 



There is very little information extant as to the domestic 

 Blattidae found in parts of the world outside Europe, but it seems 

 that there are numerous species that prefer the dwellings of man, 

 even though they only tolerate the owners. Belt says * . " the 

 cockroaches that infest the houses of the tropics are very wary, 

 as they have numerous enemies birds, rats, scorpions, and 

 spiders ; their long trembling antennae are ever stretched out, 

 vibrating as if feeling the very texture of the air around them ; 

 and their long legs quickly take them out of danger. Sometimes 



1 Naturalist in Nicaragua, 1874, p. 110. 



