PSE UDOXE I 'ROP TERA . 



ping organs. The most remarkable peculiarity of the order is 

 the fact that the copulatory organs of the male are distinct from the 

 opening of the vasa deferentia ; the former are situated on the 

 second abdominal segment, the latter on the ninth. Before pairing 

 the male conveys the seminal fluid to a bladder-like cavity on the 

 second abdominal segment ; this is done by bending the tip of the 

 abdomen forward. The pairing takes place during flight. The 

 maK :he neck of the female with his anal clasping organs : 



the female then curves the end of her abdomen to the organs on the 

 :ul abdominal segment of the male. 



The eggs are laid in water. In some species the female flies 

 back and forth over the surface of the water, sweeping down at in- 

 tervals to touch it with the tip of her abdomen, and thus wash off 

 one or more eggs into it. In other cases the eggs are laid in a mass. 

 On one occasion, in company with my class, I saw a dragon-fly pois- 

 .lerself in the air a short distance above the point where a water- 

 plant emerged from the water. At frequent intervals the insect de- 

 nied with a swift curved motion, pushing the end of her abdomen 

 into the water. On examination a large cluster of eggs were found 

 attached to the plant just below the surface. Professor Uhler has 

 observed a dragon-fly alight upon a water-plant, and, pushing the 

 end of her body below the surface of the water, glue a bunch of 



to the submerged stem or leaf. 

 The nymphs of dragon-flies (Figs. 68 and 69) pass their lives in 



68. Nymph of Dragon-fly. Agriomn*. Fir.. 69. Bxtivtc of nymph of Drmgon fly. 



the y are predacior ig on such aquatic animals 



