CHAPTER IV. 



DRAGONFLIES. 



THE Cockroach and other Orthoptera mentioned in 

 the last chapter exhibit in the course of their development 

 none of the sudden and abrupt changes of form which 

 constitute " metamorphosis." From birth they resemble 

 the adult in all but a few features, and these are acquired 

 gradually at successive moults and not merely at one or 

 two. Up to a certain point the Dragonflies exhibit 

 similar phenomena, but eventually there comes a well- 

 marked change both in appearance and habitat when the 

 insect passes from the " nymph " (pupa) stage to that of 

 the adult (imago). There is. however no period of prolonged 

 quiescence and immobility such as is familiar in the 

 chrysalis of a Butterfly or Moth, and they are therefore 

 described as having only a " partial metamorphosis." 



The entire group of Dragonflies is known as the 

 ODONATA and is best regarded as a distinct Order of 

 Insects. In England we have about 40 species. The 

 great majority seldom travel far from water, but some 

 of the larger species with strong powers of flight at times 



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