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feldom recedes, I law feveral of thefe animals which had 
been cut through the middle, perhaps by fome crab, by 
the fudden collilion of pebbles, or by fome other means, 
which though not unnatural, we may yet not be able to 
account for. They foon began to recover. I fliould have 
taken them for a new fpecies, had not my former expe- 
riments pointed out to me the gradual reproduction with 
which nature, no lefs various than impenetrable in her 
refources, kindly indulges them. Are not the accidents 
which happen to birds, quadrupeds, and even to man, 
frequently followed by effeCts, which feem intended to 
convince us, that we lay too great a ftrefs on the refources 
of art, and truft lefs than we ought to do to nature ? 
Although I could never yet arrive at any certain know- 
ledge concerning the generation of this fpecies, I fufpeCt 
that it is different from that of the others. Several 
of my fpecimens have fuddenly let fall to the bottom 
of 
aux licux d’ou la mer fe retire rarement, j’ai apper^u pluGeurs de ces animaux 
qui avoient ete coupes par la moitie du corps, peut-etre par quelque cancre, par le 
choc fubit de quelque caillou, ou par quelque autre moyen meme naturel que 
nous ne pouvons pas prevoir ; ils commen^oient a fe retablir. Je les aurois pris 
pour une efpece difFerente, fi les experiences que j’avois tentees auparavant ne 
m’avoient fait connoitre le retabliffement gradue que leur accorde la nature, dont 
les reffources fontd^autant plus inconnues qu’elles font fans nombre. Ne voit-on 
pas de temps en temps, a I’occafion des accidens qui arrivent aux oifeaux, aux qua- 
drupedes, ct a I’homme meme, des efFets qui femblent deftines a nous con- 
vaincre, que nous comptons trop fur les refFources de I’art, et trop peu fur celles dc 
la nature. Quoique je n’aye eu aucun eclaircifFement fur la generation de cette 
efpece, je foup^onne qu’elle eft difFerente des autres. Plufieurs individus ont jette 
tout 
