MUSCA. FLY. 
Generic Character. 
Os probosc’ulc carnosa, la- 
biis duobus latcralibus. 
Palpi nulli. 
i Mouth formed into a flesbv 
'' 
proboscis, -with two late- 
ral lips. 
Palpi none. 
XnE vast extent of the genus Musca makes it 
necessary to divide the whole into different assort- 
ments, in order to the more ready investigation 
of the species. These divisions are instituted 
from the form of the antennas, which are either 
simple, (without any lateral hair or plume;) or 
armed, (that is, furnished with a lateral hair or 
plume.) - These divisions^ are farther separated 
into others, according to^ more or less downy or 
hairy appearance of the insects. 
The first section of this genus comprehends 
such Flies as have simple antennar'. 
The Larvae, in the ditferent tribes of Flies, 
differ far more in hafiit than the complete insects; 
some being terrestrial, and others aquatic. Those 
of the more common kinds are emphatically dis- 
tinguished by the title of Maggots, and spring 
from eggs deposited on various ])utrid substances. 
Several of the aquatic kinds are of singularly cu- 
