THE DRAGON FLY. 43 



bier of clean water, the eggs will usually be deposited 

 there. They should be collected and taken home in water, 

 and their development studied. 



The young of the dragon fly are called nymphs. They 

 are commonly found sprawling on the bottom of shallow 

 brooks or ponds, or clinging to submerged trash or to 

 aquatic plants. Easy marks of recognition are the wide 

 head and thorax, very rudimentary wings, and a much- 

 enlarged and armed lower lip, which covers the mouth as 

 a shield. A water net will capture such as cling to sub- 

 merged green plants. Those found in trash fallen in the 

 water's edge may be raked ashore with the trash and 

 picked up by hand, their active efforts to return to the 

 water making them easy to find. All may be carried 

 home in a small pail of water. They live upon aquatic 

 insects ; and a supply of their insect food should be col- 

 lected at the same time, and placed in the pail with them. 

 A few strokes of a water net through a pool will usually 

 catch a supply of suitable food. A few submerged green 

 water plants should also be placed in the water with them, 

 to furnish oxygen. The contents of the pail may be 

 turned out into a bowl or other improvised aquarium at 

 home, and there the nymphs will live and grow, and 

 finally transform into adult dragon flies. 



Study of the Adult. Liberate a live dragon fly in a 

 closed room (it has no sting, and is in no way hurtful to 

 man), and study its actions. Note: 



1. The position of its wings in motion and at rest. 



2. The position of its legs. 



If you can time its passage across the room, make an 

 estimate of its speed in number of times its own length 

 per second. Compare this with the speed of a fast horse 

 reduced to the same terms. 



Put a live dragon fly into the cyanide bottle, and as 



