THE MOSQUITO 



85 



to contain protozoa, unicellular algae, and 

 other organic detritus. In course of time 



Anopheles 



CULEX 



Fig. 22. — A comparison between the various stages in the life- 

 history of the mosquito (Anopheles), on the left, and the gnat 

 (Culex), on the right. 



some object too big for the larva to swallow 

 is brought to its mouth by the currents, but 

 after a very short struggle this is rejected. 

 The minuter particles accumulate in the 

 chamber for a certain time, and then are 

 swallowed by a gulp-like motion and thus 

 pass into the oesophagus. 



