BARON CUVIER. 99 



(could they be convinced) to those who believe 

 in the indefinite alteration of forms in organised 

 beings, and who think that, with time and ha- 

 bits, each species might have made an exchange 

 with another, and thus have resulted from one 

 single species. However extraordinary and in- 

 comprehensible this system may appear to be, 

 which would take away the basis on which 

 science rests, and which could only be estab- 

 lished by a definition of the possible duration of 

 a species in its original state, M. Cuvier se- 

 riously refutes it, and destroys it with one 

 objection, that of not finding intermediate mo- 

 difications between an animal of the former and 

 present world, even when it approaches it most 

 nearly. He gives the definition of a species, 

 proves the constancy of certain conditions of 

 the forms which characterise it, and presents a 

 table of the variations which it is possible for it 

 to undergo. In short, he demonstrates, by a 

 scrupulous examination of the skeletons of mum- 

 mies, that the animals living in Egypt two or 

 three thousand years back, when compared with 

 those which now breathe on this classic ground, 

 have not, in the course of so many ages, under- 

 gone any important changes of form ; that even 

 among the wild animals there has been no alter- 



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