izo Insect Pirates [FOURTH WEEK 



oncoming wave. Thus they have come to be named 

 petrels little Peters because they seem to walk upon 

 the water. Without aid from the wings, however, they 

 would soon be immersed, so the walking is only an illu- 

 sion. 



But in our smallest ponds and brooks we may see this 

 miracle taking place almost daily, the feat being accom- 

 plished by a very interesting little assemblage of insects, 

 commonly called water skaters or striders. Let us place 

 our eyes as near as possible to the surface of the water 

 and watch the little creatures darting here and there. 



We see that they progress securely on the top of the 

 water, resting upon it as if it were a sheet of ice. Their 

 feet are so adapted that the water only dimples beneath 

 their slight weight, the extent of the depression not being 

 visible to the eye, but clearly outlined in the shadows 

 upon the bottom. In an eddy of air a tiny fly is caught 

 and whirled upon the water, where it struggles vigorously, 

 striving to lift its wings clear of the surface. In an instant 

 the water strider pirate of the pond that he is reaches 

 forward his crooked fore legs, and here endeth the career 

 of the unfortunate fly. 



In the air, in the earth, and below the surface of the 

 water are hundreds of living creatures, but the water 

 striders and their near relatives are unique. No other 

 group shares their power of actually walking, or rather 

 pushing themselves, upon the surface of the water. They 

 have a little piece of the world all to themselves. Yet, 

 although three fifths of the earth's surface consists of 

 water, this group of insects is a small one. A very few, 



