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HOW TO RECOGNIZE BONES 



^jfossil animals are found ; for thus we are 

 enabled to come to some conclusion as to the 

 former connexion of different land surfaces of 

 the world with one another. 



The question must have occurred to many of 

 you, — How do we recognize fragments of bones 

 found in the earth ? How do I know that a 

 fragment I may find is the lower jaw of a 

 creature like the horse ? or that bones I may 

 dig up are the bones of a tapir ? How do I 

 know that a given skull is that of a reptile ? and 

 that a given shell was inhabited by a creature 

 hke the nautilus ? 



We are able to know these and hke matters 

 because the shape of different parts of each 

 kind of animal is very constant. The kinds 

 which are hke one another in other respects are 

 hke one another in the details of their bones 

 and teeth, even in such minute points as the 

 microscopic texture of the bones. An immense 

 mass of facts about such things is known, and 

 when set out in orderly fashion is termed the 

 science of comparative anatomy or animal 

 morphography. 



The first photograph I have to show in this 

 chapter is of a piece of bone which was sent 



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