THE GOLDFISH AND ITS CULTURE. 115 
the four nearest the head are short, but the third pair are very 
long, different in shape from the others, very much resembling 
boat oars. When in the water, the insect swims upon its 
back, using the hind legs as oars for propulsion, while the front ones 
are instrumental in seizing its prey. Young fish, tad-poles, and 
also insects, all contribute to supply it with food, to the former, 
especially, itis a very 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 
THE Boat FLy. Larva OF DraGon FLy. 
that when once 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 accompany- 
