On the Falceontology of South America. 3W 



modern submersions of different extents, whose manifest traces 

 are every where to be found upon the diluvian formations of 

 the new world. In the old world, also, they also shew them- 

 selves in innumerable localities. Of this the oyster-beds of St 

 Michel- en-FHerm are a proof, as likewise those changes in 

 the level of the modern beds of the quaternary system of tho 

 north of Europe. Thus, both in America and in Europe, in 

 the later effects, as in tho earlier, we perceive a great coinci- 

 dence, both in the causes and in the results. 



Conclusions. 



From the comparison of the Palaeontological facts which 

 have been observed in the New World and in Europe, we may 

 deduce conclusions of immense importance for the solution of 

 the great general questions of geology, and of the chronological 

 history of the animated worlds at the surface of the globe. 

 The conclusions are as follows : — 



1. Living beings, taken as a whole, have, according to the 

 chronological order of the faunas peculiar to the formationp, 

 advanced, both in America and in Europe, from the more 

 simple to the more compound. Many genera, it is true, like 

 the Trilobites, Orthoceratites, and Producti, have completely 

 disappeared with the more ancient systems ; others, appearing at 

 a later period, the Ammonites, Belemnites, Turrilites, &c., &c., 

 have also become extinct with the completion of the cretaceous 

 formations; but the genera, multiplying more and more in 

 proportion as they receded from the primeval ages of the world, 

 have been replaced, during the tertiary period, by Mammalia 

 more perfect in their organization, and by marine and terres- 

 trial animal forms which were previously unknown, and many 

 of which are represented in the existing fauna. 



2. As no transition can be detected in the specific forms, 

 the living beings at the surface of the globe appear to have 

 succeeded each other, not by transition from one into another, 

 but by the extinction of tho existing races, and by the new 

 creation of species at each geological epoch. 



3. The animals are distributed by zones, according to the 

 geological epochs. Each of these epochs, in fact, represents 



