PRACTICAL CARP CULTURE. 



55 



dangerous enemy. The instrument or weapon with which the insect 

 makes the attack upon the victim is a strong, conical beak. 



It is believed that when making the attack, the boat-fly injects poison 

 into the wound it makes, as seems to be proven by the fact that when once 



THE BOAT FLY. 



LARVA OF DRAGON FLY. 



attacked, though subsequently escaping, the victim always dies in a short 

 time. When upon land, this fly crawls along, in an upright position, 

 dragging its oars behind it. In the evening, and at night, it likes to leave 

 the water and make excursions to other ponds or creeks; from this habit 

 the culturist may take warning. Its eggs are deposited against the stems 

 of aquatic plants in the early spring, and again in mid-summer, so that 

 one season produces two crops of them. 



The young make their appearance soon after^-immediately following 

 the example of the parents by swimming upon the back and eating almost 

 anything they happen to meet. The accompanying illustration shows the 

 insect as seen from below when in the water. 



There are two or more varieties of this fly that differ in coloring, and 

 of smaller size than the one described, though all are extremely destruc- 

 tive to the young fish the one delineated, more especially. 



THE YELLOW-BANDED WATER BEETLE. 



(Dytiscus marginalis.) 



YELLOW-BANDED BEETLE AND ITS LARVA. 



This rather pretty beetle, lives entirely below the surface of the water, 

 never leaving it, except during the night when the air is damp or in rainy 



