38 FOSSIL MAMMALIA. 



on a subject of this kind ; it is sufficient to observe that, by the 

 application of this principle to its utmost extent, assisted by 

 careful observation, the skilful comparative anatomist is enabled, 

 in general, from a single bone, or fragment of bone, to deter- 

 mine with accuracy the form, character, and dimensions of the 

 animal to which it belonged. I do not pretend to say that, in 

 every case of fossil remains, this method is infallible. Fossil 

 fragments may sometimes be too few, too mutilated, or of parts 

 not sufficiently influential to warrant a decided opinion. But 

 in the vast majority of instances, the induction is quite ample 

 enough to justify the conclusion. 



It is the study of fossil osteology alone which has led to any 

 precise notions concerning the theory of the earth. Had 

 organic fossils been totally neglected, no one would have ima- 

 gined that successive eras, and a series of different operations, 

 had taken place in the formation of the globe. By them alone 

 are we certified that the covering of this planet has not always 

 been the same, as it is obvious that, before they were buried in 

 its depths, they must have existed on its surface. We have 

 extended, by analogy to the primitive formations, the conclu- 

 sion with which the fossils have supplied us for the secondary ; 

 and, had the strata of the earth been destitute of organic 

 remains, it would have been impossible to maintain that their 

 production had not been simultaneous. 



It is also to the fossils, slight as our acquaintance is with 

 them even yet, that we are indebted for the little that we 

 know concerning the nature of the revolutions of the globe. 

 By them we learn that certain strata have been tranquilly de- 

 posited in a fluid mass ; that the variations in the strata have 

 corresponded with those of the fluid ; that their denudation 

 was occasioned by the translation of this fluid ; and that this 

 denudation has taken place more than once. Nothing of all 

 this could have been learned with any certainty, but for the 

 study of the organic remains. 



