300 Of the Chaviges which Life has experieticed on the Globe, 



and vegetable life. The beings, which were unable to resist the 

 influence of these various causes were destroyed ancj disappeared 

 from the earth, with the circumstances for which they were cre- 

 ated ; new species appeared with new conditions of existence. 

 But, in examining the series of fossil remains that are found 

 buried in the strata of the globe, there is nowhere perceived a 

 distinct line of demarcation between the different terms of that 

 series, so as to prove that life has been once or oftener totally 

 renewed on the earth. On the contrary, we discover in it a 

 proof of the successive and gradual change which we have point- 

 ed out. Certain primitive types have indeed completely disap- 

 peared, but they are found existing at various epochs, and their 

 remains are blended with those of more modern types ; along 

 with new species of types still existing, we find some of anterior 

 epochs ; certain genera that yet obtain are common to all the 

 terms of the series ; and toward the end of the series, we find the 

 remains of some of our present species along with ancient types 

 and extinct species. In consequence of the establishment of cli- 

 mates, life has almost entirely abandoned the polar countries, 

 and the glaciers have usurped, on the high summits, the place of 

 the verdure of primeval times. Palms, date-trees, cocoas, dra- 

 caenae, pandani, arecae, the great reed, and the arborescent ferns, 

 have forsaken our climates, together with the elephants, tigers, 

 panthers, hippopotami, the gigantic tapirs, the rhinoceroses, 

 palaeotheria, anaplothaeria, mastodons, and other extinct ani- 

 mals, as well as those enormous reptiles whose forms were so ex- 

 traordinary. Sole masters, in those times, of the countries now 

 subjected to the dominion of man, these animals are either en- 

 tirely destroyed, or now live only between the tropics. 



Man appears to have arrived upon the earth only after its sur- 

 face was adapted to receive him, after the establishment of cli- 

 mates, and when a happy equilibrium among the elements had 

 determined the permanency of the present state of things, or at 

 least had rendered its variations almost imperceptible. 



Such is a brief view of the changes which life has experienced 

 at the surface of the globe, and of the causes which have pro- 

 duced those changes. Our theory, which is founded on all the 

 facts that have been established, cannot but prevail over the sys- 

 tems hitherto proposed, for it is in harmony with the natural 



