THEORY OP THE EARTH. 109 



be explained and illustrated. In the meantime, 

 the intelligent reader may gather a great number 

 of these from the work now laid before him, if he 

 will take the trouble of attending to all the appli- 

 cations which we have made of them. He will 

 there find that it is by this method alone that we 

 have been guided, and that it has almost always 

 been sufficient for the purpose of referring every 

 fossil bone to its peculiar species, if belonging to 

 one that still exists ; to its genus, if belonging to an 

 unknown species ; to its order, if belonging to a 

 new genus ; and, finally, to its class, if belonging 

 to an unknown order : And, in these three latter 

 predicaments, to assign to it the proper characters 

 for distinguishing it from the nearest resembling or- 

 ders, genera, and species. Before the commence- 

 ment of these researches, naturalists had done no 

 more than this in regard even to such animal re- 

 mains as were found in an entire state. 



28. Results of the Researches respecting the Fossil 

 Bones of Quadrupeds* 



In this manner we have ascertained and classifi- 

 ed the fossil remains of seventy-eight different 

 quadrupeds, in the viviparous and oviparous 

 classes. Of these, forty-nine are distinct species 

 hitherto entirely unknown to naturalists. Eleven 

 or twelve others have such entire resemblance to 



* Note M. 



