42 



GENERAL ZOOLOGY 



covers. 



ite position of these insects is to float with the head down 

 and the tip of the abdomen protruding just enough to 

 admit the passage of air to chambers beneath the wing 

 The back swimmers can inflict a momentarily 

 painful wound with their sharp beaks. 

 The giant water bugs, or electric-light 

 bugs {Bena'cus, Fig. 26), are about the 

 largest living Hemiptera. They fly read- 

 ily from pond to pond and in transit are 

 fcfo frequently attracted to electric lights. 

 They become especially important in fish 

 hatcheries and ponds because they attack 

 and kill small fishes, though they also 

 prey upon aquatic insects. 



Definition of Hemiptera (Gr. hemi-, 

 "half"; pteron, "wing"). Members of 

 this order agree in possessing a sucking 

 beak and in having incomplete meta- 

 morphosis. Practically all of them have 

 two pairs of wings. The under wings are delicate and mem- 

 branous, and the outer wings have their bases hardened as 

 a protection to the under wings. On hatching from the eggs 

 the young fairly closely resemble their parents except in size 

 and in lack of wings. 



Fig. 26. Giant water 

 bug, or electric-light 

 bug. (Natural size) 



