CHAPTER II 



FLIES WITH AQUATIC 



THE GNAT (CULEX) 



SMALL stagnant pools and ditches are the favourite 

 haunts of the larvae and pupae of the Gnat. A ditch 

 in a wood choked with fallen leaves is one of the best 

 hunting grounds, and in the summer months they 

 may be found by the thousand in such places. 



The larva, when at rest, floats at the surface of the 

 water. Its head, which is provided with vibratile 

 organs suitable for sweeping minute particles into the 

 mouth, is directed downwards, and, when examined 

 by a lens in a good light, appears to be bordered 

 below by a gleaming band. There are no thoracic 

 limbs. The hind limbs, which are long and hooked 

 in the burrowing Chironomus larva, and reduced to 

 a hook-bearing sucker in Simulium, now disappear 

 altogether. A new and peculiar organ is developed 

 from the eighth segment of the abdomen. This is a 

 cylindrical respiratory siphon, traversed by two large 

 air-tubes, which are continued along the entire length 

 of the body, and supply every part with air. The 



H 



