THE DRAGON FLY 79 



(2) Observe the peculiar color and venation of the 

 wings. How do they differ from the wings of a bee and a 

 house fly? Examine the attachment of the wings to the 

 body. What motions have they? 



How do you account for the large thorax of the dragon 

 fly? 



Draw one wing showing venation (Xs)- 



Draw entire dorsal view of dragon fly (Xi)- 



Abdomen. — Count the number of segments and observe 

 the attachment of the abdomen to the thorax. 



How many spiracles' do you find? On what segments? 



The dragon fly belongs to the order Neuroptera. Is the 

 name appropriate? 



Development. — (i) The eggs are deposited in water 

 where they are soon hatched into nymphs which crawl 

 along the bottom of the water. The nymph is carnivorous 

 and very voracious, consequently it grows rapidly and 

 molts often. Before molting the last time it crawls 

 out of the water and fastening itself to some convenient 

 projecting place and breaking the shell along the dorsal 

 side, it comes out of its shell into a new world of light and 

 air which contrasts strangely with its former abode in 

 darkness and filthy water. 



(2) Nymphs may be easily obtained by dredging ponds 

 with a net. Get a few and put them in jars filled with water. 

 Feed them on insects and small crustaceans obtained by 

 dredging the ponds. 



(3) Study the nymph carefully. Do you find three 

 divisions of the body? 



How does each part differ from the corresponding part 

 in the adult? 



