130 



CIVIC BIOLOGY 



feeding upon minute forms of animal and vegetable life which 

 are swept mto their gullets by the constant motion of little 

 brush-like mouth-parts. A long respiratory tube comes from 

 the eighth segment of the body, through which the larva 

 breathes by opening it to the air. After undergoing three 

 different molts the larva reaches maturity and changes into a 

 pupa in from ten to fourteen days. The pupa differs radically 



Fig. 67. Survey of mosquito breeding places by a normal-scliool class 

 Equipment : bottles, tumblers, and saucers 



from the larva in appearance, and breathes from the ear-like 

 organs on the thorax (Fig. 62). Except when disturbed the 

 pupa remains at the surface of the water. After two days 

 it splits down the back and the adult mosquito rises from 

 the pupa skin. 



Anojyheles and Aedes lay their eggs scattered singly, those 

 of Anopheles floating while the eggs of Aedes sink to the 

 bottom (Fig. 62). The larva of Aedes resembles that of Culex, 

 while that of Ano2jheles lies horizontally, just under the surface. 



