HEMIPTERA. 195 



also serves as a tube through which the bug sucks up the 

 juices found. The bugs have an incomplete metamorpho- 

 sis (p. 182), hatching from the egg much in the adult con- 

 dition, except that wings are lacking. 



Almost all the Hemiptera. when adult, have four wings, 

 though -there are a number of wingless forms. These wings 

 are built upon two distinct patterns, and this serves as a 

 means of subdividing the Hemiptera into two groups. In 

 the one (HETEROPTERA) the basal half of the anterior 

 pair of wings is thickened while the rest is membranous, 

 and the wings themselves are held in an overlapping manner 

 upon the back when at rest. This condition is familiar in 

 the squash-bug. In the other group (HOMOPTERA) there 

 is no such thickening of the basal portion of the first pair 

 of wings, and these organs, when at rest, are placed upon 

 the sides of the abdomen. 



While most of the bugs are injurious to human interests, 

 there are some which are a benefit to man, since they feed 

 on injurious insects ; and still others, like the cochineal- and 

 lac-bugs, produce substances of value to man. 



Of the Heteropterous forms some are aquatic, and of 

 these the water-skaters, gliding over the surface of still 

 water, are familiar to all. Others live most of their lives 

 beneath the surface, and some of the larger of these water 

 bugs can kill small fish, sticking the beak into them and 

 sucking their blood. 



Of the terrestrial forms none is more widely known than 

 the bedbug, a form which is famed for its attacks on man. 

 It is one of the bugs which never develop wings. From 

 the pecuniary standpoint the chinch-bug is more important, 

 since it attacks fields of grain, doing sometimes millions of 

 dollars of damage in a single year. The young attack first 

 the roots and underground stems, and later the stems 



