86 THE GOLDFISH AND ITS CULTURE. 



ing 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 

 destructive to the young fish the one just delineated, more 

 especially. 



THE YELLOW-BANDED WATER BEETLE. 



(Dytiscus marginalis.) 



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

 water, never leaving it, except during the night when the air is 



YELLOW-BANDED WATER BEETLE AND ITS LARVA. 



damp or in rainy weather, and then for the purpose of making 

 excursions to other Idealities. The body is of a greenish black 

 color, encircled with a brownish yellow band this feature giving 

 it its name. When taken from the water it exudes a milky fluid of 

 a most offensive and disgusting odor. The hind legs are shaped 

 very much like those of the boat-fly, and serve the same purpose. 

 This beetle is very courageous, attacking fish of any size, as large 

 ones have been caught, into whose flesh the beetle had eaten large 

 holes, the beetle itself found in the hole hard at work eating up the 

 fish. The larva, which is produced twice within the same season, 

 lives and grows upon tadpoles and young fish. 



