OUR ANCIENT RELATIVES 



deemed surprising that one should seek to derive 

 the higher vertebrates from fishes whose whole 

 head and face were covered with a porcelain-like 

 armor; but in the following pages we shall follow 

 this amazing transformation step by step. 



OUR ANCESTORS COME OUT OF THE WATER 



Plant life is believed to have originated in the 

 sea in early Archeozoic times. As far back as 

 Devonian time it had succeeded after long ages of 

 struggle in adapting itself to terrestrial life and 

 there were great forests of low types of trees pre- 

 ceding the still greater swamps of the Coal age. 

 No remains of amphibians have hitherto been 

 found associated with Devonian plants, and the 

 transformation of air-breathing fishes into lowly 

 amphibians took place during the millions of years 

 in which the fossil record of vertebrate life is still 

 defective. But at the time of the formation of 

 the older coal beds of Great Britain there were 

 still surviving some very low types of amphibians 

 which retained more of the fish-like characters in 

 the skeleton than did any later forms known. 



These highly interesting remains were imper- 

 fectly described by earlier authors but they have 



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