500 A DESCRIPTION OF 
scales, which, from the multiplicity of their reflecting sur- 
faces, make the whole animul appear of a perfect pearl 
colour. This insect is furnished on each sidepf its head with 
a cluster of eyes; and each of these clusters is beset with a 
row of small bristles, much like the cilia or hairs on the 
eyelids ; and, perhaps, serving for the same purpose. It 
has two long palpi, curiously ringed or knobbed, having 
at each knob small hairs or bristles, here and there, like 
knots of fringe : besides these, it has two shorter palpi, 
knotted and fringed like the former. It has three tails, 
in every particular resembling the two longer palpi that 
grow out of the head. The body is covered with sharp- 
pointed bristles, like spears. 
ORDER VI. Uitera, or 
THIS order is characterised by having only two wings, 
which are transparent, and which have two little move- 
able bodies called halteres or balancers placed close behind 
them. The head is covered with numerous eyes ; and the 
mouth is furnished with a bristly proboscis or sucker. 
The legs are very long in proportion to the body, and 
they are in many species terminated by two or three small 
cushion-like expansions, which are supposed to enable 
them to walk on glass. Each foot has also two hooks or 
claws. 
THE HOUSEFLY. (Musca domestica.) 
THE Flies that are found in houses are of several species, 
