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eulars. View it through a microscope, you will then 

 perceive in it some annular incisions, but not very deep, 

 which discover to you its true nature, and at the same 

 time informs you, that it is nothing but the skin of a 

 worm which has become round, and has contracted a 

 hardness. Open it gently with the point of a needle, 

 you find nothing in it but a kind of pap, in which you 

 are able to discover nothing. The insect has but lately- 

 lost its form of a worm ; how has it been reduced into 

 that soft substance 1 How will that become an insect? 

 Suspend your questions, and open a cone that is less 

 recent than this. What do you discover in it? A little 

 mass of oblong, whitish flesh, in which you cannot per- 

 ceive, even through a magnifying glass, the least signs of 

 members or organs. In a. word, you have before you 

 an oblong bail. Do not imagine that this ball is a 

 case that contains a nymph, it is itself a nymph that is 

 much disguised. Press the hall a little : the legs begin 

 now to shew themselves ; they come out of a little 

 socket, that is at one of the extremities of the ball. 

 Augment the pressure by degrees, you will force all the 

 parts of the nymph to appear : they therefore exist 

 already, but they were sunk and infolded within the ball, 

 almost as the fingers of a glove might be in the hand of 

 a glove. 



If you could make the same experiment on the ovi- 

 form bodies of wef-polypuses, and on the huds of arm- 

 polypuses, that you have lately made on the oblong ball, 

 you would probably oblige the little polypus to produce 

 itself, and by that means accelerate the time of its birth. 



5. Insects that pass through the state of an o b long 

 bail can therefore form themselves a cone of their own 

 skin. All the parts of the nymph separate themselves 

 by little and little from this skin ; it grows round and 

 hard about them : and under this singular arch they 

 make an end of perfecting* themselves : they are at 

 first only of the consistence of a pap : this thickens by 

 degrees; it assumes the form of an oblong ball, and 

 when all the members of the nymph have acquired a 



