THE HEMIPTERA 



33 



There are many species of bugs that live in or on the 

 water, and these forms show many remarkable and inter- 

 esting adaptations to aquatic life. The large electric- 

 light bugs, which are so frequently at- 

 tracted by lights at night, live normally 

 in the water where they prey upon 

 small fishes and other aquatic organ- 

 isms. They are fierce fellows and in- 

 flict severely painful bites. The slender 

 water scorpion, which superficially re- 

 sembles a walking-stick in the general 

 form of its body, commonly lives near 

 the banks of ponds and streams with 

 the tip of its long posterior breathing 

 tube protruded at the surface of the 

 water. By its fore legs which resemble 

 somewhat those of the praying mantis FIG. 25. A water 

 the -water scorpion catches small crea- 

 tures that come near, and holds them while it sucks their 

 blood. 



Among the most interesting and easily studied of the 

 aquatic Hemiptera are the back swimmers 

 (Notonecta) which have the peculiarity of 

 swimming with the dorsal surface downward. 

 These insects commonly hang obliquely down- 

 ward with the tip of the abdomen at the sur- 

 face of the water to give them access to air. 

 FlG 26 _ Their backs are light colored, a circumstance 

 A back swim- which renders them more nearly invisible to 

 IMP** giauca. animals below the surface. The posterior legs 

 are especially modified for swimming, being 

 long, flattened and furnished with marginal hairs. When 

 swimming below the surface the backswimmer carries quite 

 a supply of air which gives it a silvery appearance where 



