DRAGON-FLY. 
369 
water, and prey upon whatever they can meet with 
of a manageable size. For this purpose the head is 
furnished with a flattened appendage, having a joint 
in the middle, and two very strong claws at the 
end. When the animal is not in action, this formi- 
dable apparatus is folded up so as to cover the face ; 
but when the creature intends to attack another in- 
sect, this jointed instrument is stretched out, and 
becomes of the greatest use in securing the prey. 
After continuing in the water for two years, they 
prepare for their last great change ; for a state so 
different from the former in every respect, that they 
rather appear new animals of another species, than 
the same body differently attired. In order to ac- 
complish this change they ascend the stem of some 
water-plant, and, when arrived above the surface, 
firmly grasp the plant, and for some time continue 
immoveable, as if meditating on the approaching 
change. What follows is singularly curious. The 
skin of the head and back, after a slight effort, 
bursts open, and exposes the real head and eyes of 
the libellula in all their brilliancy of colouring. 
From this opening proceeds the head, then the 
body and legs of the animal ; the empty case being 
left behind attached to the plant, where it exhibits 
a very perfect model of its former state. At first 
the new-born insect is but very weak, and sits 
quietly upon the reeds or rushes to recover itself. 
During this time the wings, which were before 
folded up and compressed into the small space 
they occupy under the skin of the chrysalis, begin 
VOL. 11. 2 B 
