THE CHAMELEON FLY. 437 



cupy almost one half of the body. Both of these 

 terminate in the open tube, or last ring. Though 

 these larva? are furnished with powers of respiration, 

 and actually respire air, yet some of them are able 

 to live more than twenty-four hours without re- 

 spiration. 



The head of this creature exhibits not less matter 

 of curiosity than its tail. In the middle part of its 

 mouth is placed a hard, pointed, horny substance, 

 immoveable, and somewhat resembling the upper 

 mendible in the beak of a bird. On each side of 

 this there is a small and very singular kind of pro- 

 cess. These have lately been discovered to be the 

 feet, or, perhaps more properly, the arms, by which 

 the animal performs many of its movements in the 

 water, and by whose aid alone it can move itself 

 forward on dry land. Another principal use of these 

 niembers seems to be to loosen the mud for the pur- 

 pose of allowing the mouth to find easier access into 

 it than it otherwise might do ; performing in some 

 measure the same functions in this respect as the 

 gristle in the nose of a hog. The animal has the 

 power of drawing these organs inward at pleasure, 

 so as to hide them as it were within the cheeks ; and 

 from this peculiar position some persons have said 

 that this larva carries its feet in its mouth. 



It is a calm inoffensive animal ; discovers no 

 symptoms of fear when man approaches, and per- 

 forms in his presence all its usual operations with 

 great tranquillity. It never attempts to injure 

 or annoy any other creature in this state of its 

 existence. 



Ff 3 



