A Period in the History of Our Planet, $ 



with the remains of these different creations, and for those 

 who are skilled in it, the sight of a single characteristic fossil 

 is often sufficient to determine to what formation its stratum 

 belongs. 



However little then — at least for the older formations, 

 down to the tertiary — it can be contested, that each epoch 

 possessed a Fauna and Flora peculiar to itself, and that with 

 the termination of every such epoch, the collective species 

 which formed its Fauna vanished from the series of living be- 

 ings, to make way for other species, as little can it be doubted, 

 that the creative energy which called all these organisms into 

 existence, approached but by little and little, and through many 

 gradations, to the creation of those forms which enliven our 

 present earth. Nay, it can even be shown, that in the great 

 plan of creation, by which the distinct periods of the ap- 

 pearance of living beings were regulated, the very commence- 

 ment exhibits a certain tendency towards the end, betrays the 

 issue towards which it is striving ; and, in the series of verte- 

 brate animals, the constantly increasing similarity to man of 

 the creatures that were successively called into existence, makes 

 the final purpose obvious towards which these successions are 

 rising. In respect to the invertebrate animals, the inquiries 

 instituted from this point of view, do not yet suffice to give 

 more than indications of a similar aim in the plan of creation. 

 It is certain, however, that the farther back we penetrate, 

 — the more ancient the formations that we investigate, — so 

 much the more dissimilar do the forms become to those now 

 existing, and so much the less can there be any idea of their 

 identity with creatures of our epoch. 



This increasing dissimilarity of forms, in proportion to the 

 age of the strata, is so striking, that a recognition of it has 

 misled many to the false conclusion, that nature at first made 

 but very crude and imperfect attempts in the production of 

 living beings, but that afterwards, upon perceiving her errors 

 and short-comings, she had destroyed the work of her hands, 

 and called a new creation into existence, until after many 

 unsuccessful attempts she had at length succeeded in calling 

 into life the crown of her efforts — man, and a creation cor- 

 responding to his wants. This false inference rests upon the 



