630 HISTORY OF GEOLOGY. 



siological reasonings, but the additional assumptions 

 which are requisite, to enable its advocates to 

 apply it to the explanation of the geological and 

 other phenomena of the earth, are altogether gra- 

 tuitous and fantastical. 



Such is the judgment to which we are led by 

 the examination of the discussions which have taken 

 place on this subject. Yet in certain speculations, 

 occasioned by the discovery of the Sivatherium, a 

 new fossil animal from the Sub-Himalaya mountains 

 of India, M. Geoffroy Saint-Hilaire speaks of the 

 belief in the immutability of species as a conviction 

 which is fading away from men's minds. He speaks 

 too of the termination of the age of Cuvier, "la 

 cloture du siecle de Cuvier," and of the commence- 

 ment of a better zoological philosophy 8 . But though 

 he expresses himself with great animation, I do not 

 perceive that he adduces, in support of his peculiar 

 opinions, any arguments in addition to those which 

 he urged during the lifetime of Cuvier. And the 

 reader 9 may recollect that the consideration of that 

 controversy led us to very different anticipations 

 from his, respecting the probable future progress of 

 physiology. The discovery of the Sivatherium sup- 

 plies no particle of proof to the hypothesis, that the 

 existing species of animals are descended from ex- 

 tinct creatures which are specifically distinct : and 

 we cannot act more wisely than in listening to the 



8 ComptR Rendu de I'Acad. des Sc. 1837, No. 3, p. 81. 



9 See p. 507 of this volume. 



