Ancient Vegetation of the Earth. 317 



phenomena, which have necessarily required so many centuries 

 for their accomplishment, were prior, in point of time, to the cre- 

 ation of man. It conducts us alike to appreciate events, and to 

 re-construct beings which have preceded, many thousand years, 

 not only the most ancient historical traditions, but also the very 

 existence of our race. 



This prolonged history of the formation of the superficial strata 

 of the earth, is constituted, like the history of nations, of periods 

 of repose, or of tranquility sufficiently great, at least, for the 

 waters and the dry land of the surface to become peopled by a 

 variety of inhabitants ; and of periods of revolution, during which 

 resistless forces have agitated this surface, elevating mountains, 

 submerging lands previously dry, and causing ancient beds of 

 oceans to issue from the bosom of the deep ; in short, pouring 

 over pre-existing rocks the materials for new layers which, envel- 

 oping the ruins of living beings, destroyed by these violent con- 

 vulsions, have thus preserved their remains as precious monu- 

 ments which now reveal to us, after so many thousand years, the 

 nature of the ancient inhabitants of our globe, and the order in 

 which the several races of beings have succeeded each other. 



The study of the periods of these revolutions, and of those of 

 repose, are alike of the most vivid interest : but the first are en- 

 tirely the province of the geologist ; while the second, on the 

 contrary, necessarily require the light of the zoologist or the bot- 

 anist ; for these alone are able, by an exact comparison of the fos- 

 sil remains of former beings with the corresponding parts of such 

 as are now existent, to determine the relations which exist be- 

 tween the inhabitants of the globe, at various and distant epochs. 

 It was thus Cuvier, in his admirable researches upon fossil bones, 

 basing his investigations upon the positive data which comparative 

 anatomy furnishes, was enabled to re-construct the skeletons of 

 the greater part of the animals of which the remains had then 

 been discovered, and also to determine, with the greatest proba- 

 bility, their exteriour forms, and their analogy to those animals 

 with which we are now acquainted. 



Botany, notwithstanding it has long furnished fewer documents 

 upon the ancient state of the globe, ought, nevertheless, to be 

 equally laid under contribution, by the geologist ; and it is even 

 able to cast more light than zoology upon the state of the terres- 

 trial surface, during the most ancient periods of its formation. 



