314 NATURALIST'S CABINET. 



Cainelion fly. 



a circle, fixes two black claws at the end of the 

 tail into two cavities formed for their reception 

 at the back of the head. It then exerts its mus- 

 cular powers, and, in suddenly extending its 

 body, throws itself sometimes to twenty- four 

 limes its own length. These maggots when about 

 to change into chrysalids, desert the cheese, and 

 in three or four days afterward grow stiffand life- 

 less. The fly bursts through an opening in the 

 skin just at the head, which there divides into 

 two parts. At its first appearance the wings are 

 not fully formed, but it is able to run about with 

 great activity: the wings expand by degrees, and 

 in the course of a quarter of an hour they are 

 perfected. Two hundred and fifty-six eggs have 

 been found in the ovary of a single female. 



The camelion fly is one of our most common 

 two-winged insects. The egg from which it is 

 produced is deposited by the female in the hol- 

 low stalks of reeds and other aquatic plants. 

 From this proceeds a larva of singular structure, 

 which is often to be seen crawling on grass and 

 plants near shallow standing waters, or floating 

 near the surface. The general colour of this 

 larva? is a greenish brown. The body consists of 

 eleven rings, and the skin somewhat resembles 

 parchment. 



Though these animals, before their transfor- 

 mation into flies, live in water, air is necessary to 

 support their principle of life; and the apparatus 

 with which nature has furnished them for that 



