v Rise of Stratigraphical Geology 203 



which their general sequence over the whole globe could 

 be determined. 



A totally new pathway of investigation had now to be 

 opened up. The part that had hitherto been played by 

 species of minerals and rocks was henceforth to be taken 

 by species of plants and animals. Organic remains, 

 imbedded in the strata of the earth's crust, had been 

 abundantly appealed to as evidence of the former presence 

 of the sea upon the land, or as proofs of upheaval of the 

 sea-floor. But they were now to receive far closer atten- 

 tion, until they were found to contain the key to geological 

 history, and to furnish a basis by which the past revolu- 

 tions of the globe could be chronologically arranged and 

 accurately described. 



Apart altogether from questions of cosmogony or of 

 geological theory, some of the broad facts of stratigraphy 

 could not but, at an early time, attract attention. In 

 regions of little-disturbed sedimentary rocks, the super- 

 position of distinct strata, one upon another, was too obvious 

 to escape notice. A little travel and observant eyes 

 would enable men to see that the same kinds of strata, 

 accompanied by the same topographical characters, ranged 

 from district to district, across wide regions. We have 

 found that it was in countries of regular and gently- 

 inclined stratified rocks that Lehmann and Fuchsel made 

 their observations, which paved the way for the develop- 

 ment of the idea of geological succession. We have now to 

 trace the growth of this idea, and the discovery that organic 

 remains furnish the clue to the relative chronology of the 

 strata in which they are imbedded. 



There were two regions of Europe well fitted to furnish 



