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THE NEW EVOLUTION 



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Fig. E. — Illustrating the relative positions in reference to each 

 other of the bilaterally symmetrical animals. The outer circle 

 (compare fig. B) represents the Vermiformes, a very highly di- 

 versified group including four distinct structural types showing 

 features w^hich are combined in four other types of more compli- 

 cated animals not directly related to them. Similar recombina- 

 tions of structural features account for all the other animal types, 

 the Vertebrata occupying the center of the figure as the most 

 complex of all animals. These different groups arose as a result 



^54] 



