CLASS I. INSECTA: ORDER 5. DIPTERA. 
681 
to every 
one ; tlie 
GNATS. 
between the two h 
MoSQUiTOS, Ciclex musquito, which, are very nearly aUiecI to the gnats, are still 
greater pests. In some parts of America, 
and in India, the inhabitants are compelled 
to protect themselves when asleep, by 
means of fine gauze curtains, from the 
attacks of these bloodthirsty little crea- 
tures. 
The female of the Common- Gnat, Cu- 
^ lex piinens^ lays her eggs, two hundred 
to three hundred in a year, one by one 
in the water ; these are joined together, 
and form a little raft, which floats on 
the surface. They are hatched in three 
days, and in fifteen days the larvae have 
reached maturity. They still inhabit the 
water, and are very active; when about 
to assume the imago state, the skin 
which covered the pupa being loosened 
from the animal within, and the space 
eing occupied with air, it fioats upon the surface of the water ; the gnat breaks 
through the upper part, and stands on the skin 
it has quitted, and which now serves as a little 
boat, upon which it floats until it has attained 
strength to fly. There are many species of gnats, 
some of which are harmless ; others are not only 
troublesome to man, but to cattle, beasts, and 
birds, sucking their blood, and causing the most 
irritating pains and itchings in the skin. The 
mosquitos, of which there are several species, are 
hatched in nearly the same manner as the gnats. 
THE TIPULID^. 
These have the proboscis short, terminated 
by a pair of fleshy lips, inclosing two bristles. 
The Meadow-Tipule of Europe, Tipula ole- 
racea, is common in the blades of grass. The 
common T{pul(^, or Daddy Long-Legs, are 
well-known examples of this family. Their 
larvss live in moist ground, and often do great 
mischief by eating the roots of grass in mead- 
ows. The Hessian-Fly, Cecidomyia destructor, 
is noted for its ravages among the wheat crops of 
this country. Its larvae attack the stems of the 
plants near the ground, while those of the Wheat- 
Fly, C. tritici, feed on the flowers, and render 
them abortive. The ravages of these insects,, 
at particular seasons, have often caused dam- 
age to the amount of millions of dollars in a 
single year. 
THE (ESTRID^. 
MOSQUITOS. 
THE MEADOW-TIPULE. 
This family includes the Gad-Mies and Breeze 
or £ot Mies, so troublesome to cattle and 
horses. The Ox-Fly, (Estrus bovis, is three-fourths of an inch long, and lays its eggs in the 
