LECTURE III. 



EVOLUTION AS TESTED BY THE RECORDS OF THE 



ROCKS. 



HAVING discussed those vague analogies 

 and fanciful pedigrees by which it has 

 been attempted to drag the science of Biology 

 into the service of Agnostic Evolution, we may 

 now turn to another science — that of the earth 

 — and inquire how far it justifies us in affirming 

 the spontaneous evolution of plants and ani- 

 mals in the progress of geological time. This 

 subject is one which would require a lengthy 

 treatise for its full development, and it cannot 

 be pursued in the most satisfactory way without 

 much previous knowledge of geological facts 

 and principles, and of the classification of ani- 

 mals and plants. On the present occasion it 

 must therefore be treated in the most general 

 possible manner, and with reference merely to 

 the results which have been reached. There 

 is the more excuse for this mode of treatment 

 that, in works already published and widely 



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