WATER STRIDER 125 



Drop a fly on the water and see what the water strider does. 

 Do you see a dent or dimple on the surface of the water under 

 each foot of a water strider ? The insect does not swim 

 through the water, but walks on the top of it. 



On a sunshiny day you may see a bright ring 'around the 

 shadow of each foot of a water strider. What makes the ring ? 



Whirligig Beetles. Wherever you see water striders you 

 are likely to see crowds of small, black beetles, on the surface 

 of the water, darting to and fro. They swim on the top of the 

 water so fast that they appear to be whirling round and round. 

 They can dive and fly as well as they can swim. Catch one, if 

 you can, and look at its paddlelike feet. 



Flying Insects under Water. Sweep the grassy edge of a 

 pond or pool with a scoop net. Among^ other interesting 

 things you will be likely to get winged insects that live under 

 water most of the time. One kind is a brown, flat insect, two 

 inches or more in length, and is called a giant water bug. 

 These bugs often fly around bright electric lights at night. 



You may also catch two other kinds of smaller flying bugs. 

 One swims on his back and is called a back swimmer. Another, 

 the water boatman, keeps one pair of legs thrust out side wise, 

 and uses them as if they were oars. When under water, all 

 these bugs carry, beneath their wings, a supply of air for 

 breathing. This air under water gleams like silver. 



Mosquito Destroyers. Water striders and whirligig beetles 

 live on other insects which they catch on the surface of the 

 water. They are fond of wigglers, and catch great numbers 

 of the malarial kind, for these wigglers float with their backs 

 halfway out of water. The back swimmers and water boatmen 

 catch all kinds of wigglers under water. Few mosquitoes can 

 grow in pools where these four kinds of insects live. 



