382 THE LIFE OF AN INSECT. 



with a lens near the spot where the wings are con- 

 nected to it, he will succeed in discovering two 

 organs of a curious kind. One of these, is a small 

 membranous piece connected with the trunk-end 

 of the wings, and is generally called the winglet, 

 or alula. The other looks like a little drum- 

 stick hanging down, and is called the balancer, or 

 poiser, or in Latin, the halter, or bridle. It is not 

 clear of what use either of these organs is. Since 

 the winglets are the largest in the heaviest bodies, 

 and are altogether wanting in the lightest, it 

 appears probable that one of their principal uses 

 is to assist the wings during flight. If one might 

 hazard the conjecture, perhaps they act like the 

 parachute of a balloon. As to the so-called 

 balancers, it has been considered that they serve to 

 poise the insect while flying. Dr. Derham consi- 

 dered that they kept the body steady during flight ; 

 and he states that if either a poiser or a winglet is 

 cut off, it will fly awkwardly and unsteadily, as if 

 it had lost some very necessary part. Another 

 observer states, that he cut off the winglets of a fly, 

 leaving both its wings and poisers; but it could 

 no longer fly. He also cut off, in another fly, the 

 poisers alone, and the same result took place. On 



