THE EVOLUTION OF MAN 



attachment of the lower jaw to the skull in rep- 

 tiles and mammals represents the two extremes 

 of two independent methods. 



Now the study of the fossils of the primitive 

 world gives us some clue toward a solution of 

 these contradictory questions. The historical 

 time which we should expect to represent the 

 transformation of the most ancient duckbill- 

 like mammals from the archetype next below 

 them in the scale of evolution, would be about 

 the transition from the Primary to the Second- 

 ary period, that is to say, a time midway between 

 the carboniferous and the first great saurian 

 epoch. As it happens, it is precisely this time 

 which again gives us some fossil testimony 

 touching unmistakably on the question now un- 

 der discussion. 



The present living representatives of am- 

 phibians, such as newts, toads and frogs, were 

 evidently not in existence at that early period. 

 They are apparently a late bud on the branch 

 of amphibian descent. But in their place there 

 existed very strange and large amphibians, some 

 of them resembling crocodiles with more or less 

 solid bony armor. These amphibians possessed 

 many reptilian marks, so that they give the im- 

 pression that they were in transition from am- 

 phibians to reptiles. 



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