FLY. 
383 
down the middle. Its larva, which is an inhabit- 
ant of stagnant waters, is of a still more remark- 
able appearance than that of the immediately pre- 
ceding species, which it resembles in size, but is 
of a paler colour, and furnished with a tail of 
greater length, composed of a double tube, the 
interior of which is very slender, extensile at the 
pleasure of the animal, to a vast length, and ter- 
minated by a very small spiracle. Ihe length of 
this tube is therefore varied according to the 
greater or smaller depth at which the insect chuscs 
to continue; the tip reaching to the surface, in 
order to supply the requisite quantity of air. 
Sometimes great numbers of these maggots are 
found coiled or twisted together by their tails, in 
such a manner that it is by no means easy to se- 
parate any one from the rest. The Chrysalis re- 
sembles that of the Musca tenax\ the remains of 
the tail being visible in a dried and contracted 
state. The complete insect is frequently seen on 
flowers during the autummal season. 
Among the hairy or bristly Flies with plumed 
antennae stands the well known species called 
Musca carnaria*, or the common large Blow-Fly. 
This, as every one knows, deposits its eggs on 
animal flesh, either fresh or putrid. The larv'ae 
or maggots hatch in about the space of a few 
hours, and when full grown, which happens in 
eight or ten days, are of a white or yellowish 
* Musca vomitorla. Lin, 
