FIELD BOOK OF PONDS AND STREAMS 



These water-bugs are predacious upon smaller insects. 

 Hungerford fed the nymphs with mosquito wrigglers. They 

 winter as adults in the bottom trash and mud. 



Electric-light bug, Lethocerus americanus. — In these giant 

 water-bugs the femur of the front leg has a groove into which 

 the tibia can be folded (Fig. 176). They are fiercely preda- 

 cious, devouring dragonflies, and young fish whenever they 

 are available, and Britton records the capture by Lethocerus 

 of a young pickerel which was three and five-eighths inches 

 long. 



The brownish, oval eggs, about one-fifth of an inch long, 

 have been found on reeds above the surface of the water. 

 These bugs do not hesitate to leave the water, flying some- 

 times for a considerable distance, thus migrating from pond 

 to pond. They have been captured around electric lights 

 and so earned their popular name. Adults, one and one 

 half inches long. 



Fig. 177.— Front leg of giant electric-light bug, 

 Benacus griseus, which has no groove in the femur. 



Giant water-bug, Benacus griseus.— This electric-light bug 

 (Fig. 177) is slightly larger and very similar to the preceding 

 Lethocerus americanus (Fig. 176) except that the femur of its 

 front leg does not have any groove for the tibia. It can in- 

 flict a very painful wound with its beak. 



The large streaked eggs are attached to plants above the 

 water line and the egg-clusters are two or three inches long. 

 Dr. J. G. Xeedham has written a description of the hatching 

 illustrated with a photograph that shows a young Benacus 

 pushing back the loosened caps at the free ends of the eggs. 



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