FISH ENEMIES 



99 



but there is doubt about their attacking fishes. They have been kept in 

 aquaria with them without doing damage. On general principles, how- 

 ever, it is best to exclude all beetles, large or small. 



Water Strider (Hydrobatidoe). Another of the predaceous aquatic 

 insects is the Water Strider. Quite as well known as the Whirligig 



Fig. 77. Water Strider (Life size) 



Beetle, it adopts somewhat the same methods of securing its prey, 

 darting over the surface of the water, waiting for the stream to bring 

 down some helpless insect victim that has fallen overboard. They are 

 capable of catching young fishes which come to the surface. 



Giant Water Bug (Belostomatidce), also known as the Electric 

 Light Bug, is one of our common bugs, both on land and in water. 

 Flying clumsily but strongly before electric lights, or patiently awaiting 

 a victim at the bottom of a pond, the bug is one and the same. They 

 are fiercely predaceous and very powerful. While this is a vicious enemy, 

 it is not one that frequently* gets into the fish tank except by flight, 

 and as only the adults fly they are easily detected by their size. In 

 large outdoor rearing pools or lakes they are a very practical menace. 



Figs. 78 and 79. Giant Water Bugs (B. serphus and B. americana). The smaller a 



Male With Eggs on Back (Life size) 



The colors range from clear, dark reddish brown to dull olive. With 

 some of the smaller genera, Serphus and Zaitha it was supposed that 

 females lay the eggs on their own backs. Some writers have accepted 

 this popular misconception without investigation. It has been fully 

 established that the female fastens her eggs on the back of an unwilling 

 male, who only submits to the indignity after a struggle. 



