OUR FACE FROM FISH TO MAN 



WHAT WE OWE TO THE EARLY REPTILES 



The recent frogs, newts and salamanders, as 

 every high school student knows, go through a 

 fish-like or tadpole stage of development in the 

 water and resort to this ancestral medium at the 

 breeding season. The presence of fossilized gilled 

 young of amphibians in the Coal ages shows that 

 this water-breeding habit dates back very early 

 in geological time and is in harmony with the 

 origin of amphibians from swamp-living fishes. A 

 great and revolutionary advance occurred when 

 some daring amphibians succeeded in raising their 

 eggs entirely on dry land, for thus arose the rep- 

 tilian grade of organization and with it came the 

 possibility of all higher forms of life, including man. 



With regard to the bony face, the most primitive 



known reptile, Seymouria, has much in common 



with the older amphibians. It still retains the otic 



notch characteristic of the older forms and on its 



skull roof it preserves the full complement of small 



bony plates inherited from the amphibians and 



lobe-finned fishes. Also its outer upper jaw bones 



(maxillae) still retain their primitive slenderness. 



In the same age which yielded Seymouria (the 



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