HEMIPTERA 



99 



the pond. This tube conducts the air to two spiracles at the caudal end 

 of the abdomen. 



The most common members of this family- 

 belong to the genus Rauatra (Fig. 153). These 

 are long, slender bugs with long, slender legs. 

 The only other representative of the family 

 found in the United States is Nepa apiculata. 

 In this species the body is oval, flat, and thin, and 

 measures about two-thirds of an inch in length, 

 not including the breathing-tube (Fig.. 154). 

 s*^ ^ -v^ The water-scorpions live 



^*»w^ g^^ among rubbish or on the stems of 

 ^~v Jtty-^ water-plants, in ponds and in the 

 ^f quiet parts of our streams. They 

 JSjL Ib^ are carnivorous, and have the 

 I ■ H ] first pair of legs fitted for seizing 

 / ^Hr I P ,v . v - ^n these legs the coxa is 

 ▼ very long, and the femur is fur- 



nished with a groove into which 

 I the tibia and tarsus fit like the 



blade of a pocket-knife into the 

 epa handle. 



The eggs of these bugs are in- 

 serted in the decaying tissues, often stems, of 

 aquatic plants. Although these insects are aquatic the second and hind 

 pairs of legs are fitted for walking rather than for swimming. 



Fig. 154. 

 apiculata. 



Fig. 153. — A water-scorpion. 



Family Belostomatid^; 

 The Giant Water-bugs 



The common name "giant water-bugs" was applied to this family 

 because it contains the largest of the Hemiptera now living. 



The members of this family are all wide and 

 flat-bodied aquatic insects. The fore legs are 

 for grasping, the middle and hind legs are 

 fitted for swimming. At the caudal end of the 

 body there is, in the adult, a pair of narrow, 

 strap-like respiratory appendages, which are 

 retractile. 



These insects are rapacious creatures, feed- 

 ing on other insects, snails, and small fish. Like 

 other water-bugs, they fly from pond to pond 

 and are frequently attracted to lights. This 

 is especially the case where electric lights 

 are used, into which they sometimes fly and are 

 killed by hundreds. On this account they are 

 known in many parts of the country as ' ' electric- 

 light bugs." 



Figure 155 represents Lethocerus americanus. 

 In Lethocerus, the front femora are grooved 

 for the reception of ,the tibia?, as in the pre- fig. 155. — Lethocerus americanus. 



