482 



THE INSECT WORLD. 



Laccophilus minutus. 



j Fig. 492- . 

 Hydaticus grammicus 



The Gyrinida, which come very near to the Dytistidce, like 

 water which is clear and a little agitated. They are small black 

 insects, living in troops, and which swim with rapidity, describing 

 incessantly capricious circles, which has gained for them the name of 



Fig. 494. Gyrinus natatc 



Fig. 495. Larva of Gyrinus natator. 



" Whirligigs." They are remarkable for the disposition of their eyes, 

 which are double ; so that the Gyrinidcz seem to have four eyes. The 

 lower ones look into the water and watch for the prey or the fish that 

 advances as an enemy ; whilst the upper eyes look upwards towards 

 the air, and warn the insect of the approach of enemies from above. 

 To escape from fish, the Gyrinus jumps out of the water, and also 



