576 
Insects. 
THE GREAT DRAGON FLY. (Libellula grandis.) 
This genus of insects is well known to every one. The 
larva lives in the water, and wears a kind of mask, 
which it moves at will, and which serves to hold its 
prey while it devours it. The pupa closely resembles 
the larva in its form, except that at the sides of the body 
the wings are seen enclosed in thin cases. The period 
of transformation being come, the pupa goes to the 
water-side, and fixes on a plant, or sticks fast to a piece 
of dry wood, in which position it remains for some little 
time, when the skin of the nymph splitting at the upper 
part of the thorax, the winged insect issues forth gra- 
dually, throws off its slough, expands its wings, flutters, 
and then flies off with gracefulness and ease. The ele- 
gance of its slender shape, the richness of its colours, 
the delicacy and resplendent texture of its wings, render 
it a beautiful object. It is in length about four inches. 
The female deposits her eggs in the water, from which 
spring the larvas, which afterwards undergo the same 
transformations. 
The Day Fly (Ephemera), so called on account of the 
shortness of its life, is a small insect originating from a 
larva residing in rivers. After remaining several months 
in the creeping state, a nymph is formed, from which 
