'250 
EPHEMER.i. 
of riv^iilets and stagnant waters. It is of a greenish 
brown colour, with transparent wings, elegantly 
mottled with brown, and is furnished at the ex- 
tremity of the body with tiiree very long black 
bristles. It flutters during the evening about the 
surface of the water, but during the day is gene- 
rally seen in a quiescent posture, with the wings 
closed, and applied to each other in an upright 
position. The larva is of a lengthened shape, 
about an inch in length, furnished along each side 
of the body with several finny plumes, and at the 
tail with three long, feathered processes: it has 
also a pair of moderately long antennae, though 
those of the complete insect are extremel}^ sliort. 
When arrived at its full size, as above-described, 
it exhibits the rudiments of wings on the back, in 
the form of a pair of oblong sheaths or scales : its 
colour is a pale yellowish or whitish brown. It is 
supposed to continue two years in this state of 
Larva before it changes into the complete insect. 
This change takes place in the evening, when the 
larva rises to the surface of the water, and soon di- 
vesting itself of its skin, flies to some neighbouring 
object, and after having remained some time longer, 
again casts its pellicle, and ajipears in its ultimate 
or perfect form, in which, as well as in its larva 
state, it is a favourite food of several kinds of fishes, 
and particularly of the Trout. In some seasons 
it is extremely plentiful, the air in the immediate 
neighbourhood of its natal waters being frequently 
blackened by its numbers during the evening 
hours. We are assured by Scopoli, that such 
