THE INSECT WORLD. 



Fig. 491. 

 Laccophilus minutus. 



Fig. 492. 

 Hydaticus grammicus. 



Fig. 493. 

 Pelobius Hermanni. 



The Gyrinidce, which come very near to the Dytiscidce, Hke 

 water which is clear and a Uttle 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 natator. 



Fig. 495. — Larva of Gyrinus natator. 



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

 which are double \ so that the Gyj^iftidcE 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 Gyj'imis jumps out of the water, and also 



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