BRITISH INSECTS 



the head held downwards and the tail extruded. It 

 moves about by jerky motions, sweeps into its mouth 

 microscopic food by means of a profusion of hairs, and 

 maintains itself at the surface (the creature itself being 

 heavier than water) by floating on the surface-film with 

 which the pond, or other water, is covered. The pupa 

 is quite unlike the larva, being almost a fully-formed 

 adult, though shrouded in a transparent skin. It now 



CrioT 



extrudes its head instead of the tail, as the air-tubes 

 have become exactly reversed. Very soon the pupal 

 skin splits along the back, and the perfect insect makes 

 good its escape. The adult male may be known by its 

 bushy feelers, and it is only the female which possesses 

 a piercing apparatus. She deposits her eggs in the water, 

 and these, being sticky, adhere to one another. Two 

 to three hundred of these will be laid at a " sitting," 

 and when all are fastened together, a little raft is formed 

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