TRANSFORMATION OF INSECTS. 5 



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 s})lits 

 on the back between the breathing-tubes, the head, body, and 

 limbs of a mosquito suddenly bui'st fi'om 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 flill-fed maggot, that has rioted in filth till its tender 

 skin seems ready to burst Avith 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 wonderflil chanf^'es 

 have taken place within the seed-like shell, one end of the 

 shell is forced off, and from the inside comes forth a buzzino- 

 fly, that drops its former filthy habits with its cast-off di'ess, 

 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 



