ORDER V. NET-WINGED INSECTS. 227 



them dying on the same day in which they were born. 

 The name of Day-flies was given them many years ago by 

 Aristotle and Pliny (Ephemerius Diaria), and the same char- 

 acteristics that made them an object of curiosity then at- 

 tach to them now. They are quite handsome little creat- 

 ures, carrying their citron-colored wings perpendicularly to 

 their backs, like butterflies, among whom they might be 

 placed were not their birth-place and their metamorphoses 

 so different. Besides, in their winged form they live only 

 long enough to deposit their eggs, and then die. 



For the short duration of their ethereal life, however, 

 they are sufficiently indemnified by their long existence as 

 larva and pupa, those conditions continuing from two to 

 three years, during which time they dwell under the water 

 on the muddy ground, which is their food. The larvae pro- 

 ceed from a ball, or cluster of numerous eggs, which have 

 been deposited in the water by the female fly. They are 

 of a brown color, composed of fourteen joints, and have two 

 black eyes, two antennae, short fore feet directed outward, 

 like those of a mole, for the purpose of digging, and their 

 whole body is only about an inch long. 



After they have attained their full size, generally in the 

 months of June or July, they swim to the surface of the 

 water, where they cast their skin and fly off into the air at 

 the same moment, so that it seems as if they really flew out 

 of the water as perfect insects, without undergoing any 

 transformation. Every where the eyes are turned thou- 

 sands upon thousands of them are seen arising from the 

 surface of the water, like a series of rockets. In the same 

 moment that the pupa are seen swimming on the water, 

 they are also seen flying up into the air in their perfect con- 

 dition. If one is in a boat, and stretches out his hand to 

 catch a swimming pupa, he will have instead the perfect 

 day-fly, for their metamorphosis takes place the moment 

 they feel the atmospheric air. 



