CHAPTER XXIII 



INSECTA {continued) 



Order VI. ; Diptera. (continued) 



Sub-order 2 : Nemocera (Thread-horned flies). 



Besides the types of Diptera described in the previous 

 chapter — in all of which the perfect insect was a thick-bodied 

 fly, more or less resembling a blue-bottle fly in general form- 

 there are others which resemble, instead, a gnat or midge, 

 having long, slender legs and long, narrow, usually hairy 

 wings ; also they possess the many-jointed, long antennae 

 which give the name of Nemocera to this sub-order. 

 Here again many families are included. 



Family 1 ; Culicidab (Gnats, Mosquitoes, etc.) 



The Culicidae are characterised by their long projecting 

 proboscis, and by their plumed antennae. 



Type : The Common Grey Gnat (Culex pipiens). 



These buzzing, irritating little creatures, with their annoy- 

 ing sting, are perhaps only too familiar to us in their winged 

 state, and it may be that we approach the study of their life- 

 history without much pleasurable anticipation; but we are 

 rewarded by the discovery of a story of unexpected interest, 

 displaying at every stage beautiful adaptations of structure 

 and habit to suit the changeful life they lead. 



The form of the winged imago is shown in Fig. 



260. The male can be at once distinguished from 



the female by his very bushy antennae and much longer palps ; 



339 



