TRANSFORMATION OF INSECTS. 
and take another form, wherein they remain rolled up like a 
ball, and either float at the surface of the water, for the pur- 
pose of breathing through the two tunnel-shaped tubes on the 
top of their backs, or, if disturbed, suddenly uncurl their 
bodies, and whirl over and over from one side of the vessel 
to the other. In the course of a few days these little water- 
tumblers are ready for another transformation ; the skin splits 
on the back between the breathing-tubes, the head, body, and 
limbs of a mosquito suddenly burst from the opening, the 
slender legs rest on the empty skin till the latter fills with 
water and sinks, when the insect abandons its native ele- 
ment, spreads its tiny wings, and flies away, piping its war- 
note, and thirsting for the blood which its natural weapons 
enable it to draw from its unlucky victims. 
The full-fed maggot, that has rioted in filth till its tender 
skin seems ready to burst with repletion, when the appointed 
time arrives, leaves the offensive matters it was ordained to 
assist in removing, and gets into some convenient hole or 
crevice ; then its body contracts or shortens, and becomes 
egg-shaped, while the skin hardens, and turns brown and 
dry, so that, under this form, the creature appears more like 
a seed than a living animal ; after some time passed in this 
inactive and equivocal form, during which wonderful changes 
have taken place within the seed-like shell, one end of the 
shell is forced off, and from the inside comes forth a buzzing 
fly, that drops its former filthy habits with its cast-olf dress, 
and now, with a more refined taste, seeks only to lap the solid 
viands of our tables, or sip the liquid contents of our cups. 
Caterpillars, grubs, and maggots undergo a complete trans- 
formation in coming to maturity ; but there are other insects, 
such as crickets, grasshoppers, bugs, and plant-lice, which, 
though differing a good deal in the young and adult states, 
are not subject to so great a change, their transformations 
being only partial. For instance, the young grasshopper 
comes from the egg a wingless insect, and consequently un- 
able to move from place to place in any other way than by 
