73 Mosquitoes 



proportion to the body, the hairs proportionately 

 longer and usually fewer ; and the larva is more 

 transparent and colourless than in the later stages. 

 Young larvae seem to be attracted to light in the first 

 day or so, massing on the side of the jar next the 

 window. Later many species avoid the light. When 

 moulting, the skin splits on the back of the larva's 

 thorax. The whole lining of the tracheae and intes- 

 tine is shed also. It sounds uncomfortable and 

 dangerous, yet few larvae die in the process. Before 

 a larva moults, he stops feeding for a time and keeps 

 quiet. Sometimes he lies on the bottom as if dead. 

 Then he generally comes up and begins to jerk vi- 

 ciously every little while, snapping his head from side 

 to side. The contortions increase in frequency and 

 force until the skin splits and the larva shakes himself 

 out of his old suit and swims away. After this he 

 usually appears to be furiously hungry, and falls to 

 as if he were just over an attack of typhoid, but he 

 never seems to die of indigestion or overeating. 



I closely watched the emergence of a pupa of IV. 

 smithii from the larval skin and took the following 

 notes. The larva, when first observed, was thought 

 to be dead, but under the microscope was seen to be 

 twitching the muscles of the breathing tube, no other 

 motion being apparent. The breathing tubes of the 

 pupa were plainly visible through the chitin of the 

 neck of the larva, the pupal head being forming in 

 the lower part of the larval head. When placed in a 

 deep cell the larva lay perfectly quiet, the head, 

 thorax, eighth and ninth abdominal segments, and 

 the tube being bent downward. The position slowly 



