296 THE LIFE OF AN INSECT. 



prepares for leaving that state and becoming a 

 perfect insect by raising itself to the surface of the 

 water, stretching out its body there, the thorax, 

 or, in simpler language, the front enlarged part 

 being raised above it. Immediately the eye of the 

 observer detects the fact that some change is taking 

 place in the insect ; the enlarged portion cracks 

 and splits, and through this opening the head of 

 the gnat makes its appearance ; then the trunk of 

 the insect rises in a curious manner through the 



Escape of the Gnat from its Pupa-case. 



breach, and more and more of its body rises, pre- 

 serving all the time a perpendicular position, so 

 that it looks just as if it were rising out of the 

 water, and not out of the horizontal pupa case 

 floating on the surface. The upright body of the 



