HABITS OF HETEROPTERA. 23 



fields. Few species occur in dense woodland, and those mainly 

 on the boles of trees, in the moss growing on or about their 

 roots or in bunches of dead leaves which have collected in the 

 forks of their branches. Many species fly to light, especially 

 during the mating season. 



In mating the terrestrial bugs mostly pair end to end. How- 

 ever, in the Phymatidae, and perhaps other families, the male 

 mounts the back of the female as in the Coleoptera. Their 

 eggs are deposited on or near the host plant, and after hatch- 

 ing the young moult or change the outer skin four or five 

 times, at intervals of a few days each, to become adults. 

 Growth is thereby permitted, the wing pads and body after 

 each moult become one size larger and aside from size and 

 absence of wings, there is usually but a slight difference to be 

 noted between nymphs of the last two stages and the adults. 



Defensive Habits. — When approached or disturbed many 

 species of bugs feign death, folding their antennae and legs 

 closely beneath the body and therefore, if above the ground, 

 tumble thereto. Others are very alert, quickly flying when 

 alarmed, while some of the ground frequenting species, as the 

 long-necked Myodocha serripes (Oliv.), when uncovered run 

 swiftly to a new hiding place beneath nearby debris. When 

 handled, or often when captured in the sweep net or beaten 

 into an umbrella, those species with osteola present emit their 

 characteristic defensive odor. In many species this odor is 

 not unpleasant, and that of some has been likened to the smell 

 given off by a ripe pear. In the family Pentatomidae or "stink- 

 bugs" and Coreidae or squash-bugs it is, however, notorious 

 and offensive. Birds, and people too, for that matter, soon 

 learn to avoid the bugs which excrete this odor. Many a boy, 

 while berry hunting in the country, has clapped a number of 

 berries into his mouth, only to experience a smarting sensation 

 and a nauseating taste, brought about by the acidulous liquid 

 from the glands of a stink-bug which accompanied the berries. 

 In this way, if in no other, the boy learned the virtues of the 

 protective principles possessed by the stink-bug tribe and 

 future stink-bugs, if not the one in the mouth, profited as a 

 result. Birds probably learn to avoid the use of stink-bugs as 

 food in much the same manner ; though, like many other traits 

 of the lower animals, this knowledge may in them be instinctive 

 rather than acquired. 



The beak of many species of bugs is used as a defensive 



