66 



BRANCH ARTHROPODA. 



FIG. 105. 



communities. The several individuals are the males, 



queens,* soldiers, and workers. 

 They are extremely destructive 

 to wood-work, and often attack 

 books and manuscripts. 



The eggs of the Dragon-flies, 

 or Darning-needles, are deposited 

 in the water, where the young 

 undergo their metamorphosis. 

 The full-grown pupa finally as- 

 cends the stem of some plant, 

 where it splits open along its 

 back, and the adult crawls out, leaving the old shell be- 

 hind. In this condition (per- 

 fectly harmless to man), it con- 

 tinues to lead a carnivorous 

 life, destroying large numbers 

 of mosquitoes, flies, etc. 



FIG. 106. 



Libel 'lu la deprfs'sa. Dragon-fly. 



FIG. 107. 



Larva of Dragon-fly. 



Here also belong the May- 

 flies, swarms of which are often 

 seen on warm spring evenings. 

 The young undergo their trans- 



* At the time of oviposition (5 m po z\' sMn) 

 the abdomen of the queen becomes greatly 

 enlarged by the presence of .the ova. As 

 many as 80,000 eggs have been known to 

 be deposited in a single day from such an animal, of the African species. 



Ephem' e ra vul gci' (a. May-fly. 

 B, Larva of May-fly, 



