xvin INSECTA : ORTHOPTERA 269 



projecting from the end of the body in the male shown in 

 Fig. 199. The use of these is not clear. 



Spiracles, for the passing in and out of air in respiration, 

 are present laterally on some segments of both thorax and 

 abdomen, the interchange being effected by the externally 

 visible contractions and expansions of the latter. 



Hiding all day in narrow cracks and crevices, 



into which its flat body can all too easily slip, it 



is at night that cockroaches come out in their hordes to 



feed on whatever animal or vegetable matter they can find, 



apparently eating little but tasting much. 



They dislike the cold, and at the approach of winter most 

 of them disappear, though in a warm kitchen many may 

 remain active all the year round. Few other animals seem to 

 like them for food, probably because of the evil-smelling fluid 

 given out by a pair of glands on the upper side of the abdomen. 

 The hedgehog, however, is not dainty, and will devour them 

 in great quantities, and hence it is often introduced into a 

 house when the insects have become a pest. Rats, cats, and 

 frogs also occasionally eat them. 



Cockroaches breed in the summer months. The eggs are 

 laid, sixteen at a time, enclosed in a little reddish - brown 

 horny capsule (Fig. 199). This is formed within the body, 

 and female cockroaches are often seen running about with 

 it protruding slightly from the end of the body. It is finally 

 deposited in some dark sheltered crevice. The eggs lie in 

 t\vo rows within the capsule, and the young, when ready, 

 push their way out at the straight longitudinal ridge which 

 runs along the top of it. They are very small and at first 

 pale coloured, but they rapidly darken, and when they are 

 a year old, wing rudiments appear. 



Family 2 : FORFICULIDAE 

 Type : The Common Earwig (Forficula auricularia). 



Earwigs are common garden insects with a bad reputation, 

 in spite of which they live on the whole very blameless lives, 

 feeding chiefly on decaying vegetable matter, though they do 

 also, to some extent, nibble the petals of a few flowers and 

 perhaps some fruits, in attempting to get the sweet juices of 

 which they are fond. Their reputation is further blackened 



