160 INSECT TRANSFORMATIOXS. 



It may not be improper to guard our younger read- 

 ers against mistaking for these telescopic-tailed larvae, 

 an animal, found in the same situations, \vhich has a 

 considerable general resemblance to tiiem, though 

 it is not even an insect, but a water-worm (.\*ojs), up- 

 on which Bonnet made numerous curious experiments. 

 The nais may be easily known by its being reddish, 

 while the maggot is of a dirty white colour. 



It apjiears to be the nais, or some similar fresh-wa- 

 ter worm, which medical men, unacquainted with na- 

 tural history, have supposed to get into the human 

 stomach through the medium of water, as we shall 

 presently notice. 



A no less singular structure for respiration than that 

 just described, occurs in the aquatic larvte of the 

 dragon-flies LibeUididw, Leach), which differs so 

 remarkably from the perfect insects in the beauty of 

 colour and elegance of form that has procured for 

 them the gallant appellation of damsels {demoiselles) 

 in France. This title agrees as badly with their 

 habits as the popular English name of horsc-stinoers, 

 since they have no apparatus ibr stinging ; ' and so 

 far,' says Rl-aumur, ' from seeking an innocent nutri- 

 ment in the pulp of fruits, or the nectar of flowers, 

 they are more like amazons than damsels, hovering 

 in the air only to pounce upon other insects, which 

 they crush with tiieir powerful mandibles. Should 

 they quit the margin of a pond or the banks of a 

 rivulet, where they may be seen hawking about in 

 multitudes, it is only to pursue and seize the moth or 

 the butterfly, that has fled tor shelter to the bushes.' 



Though these larvae are furnished with si.x feet, 

 they not only move very little, but do not use them 

 for walking so much as for capturing their prey. 

 Their motion is effected by a very peculiar method. 

 When one of these larvae is procured from the bottom 

 of a pond or the pool of a brook, let it be put into a large 



