THE EVOLUTION OF MAN 



through its first stages in the ranks of the mar- 

 supials. In other words, the marsupials repre^\ 

 pent the genuine ancient transition form from aj 

 Uower to a higher mammal. We shall have to 



A SPECIES OF PERAMELES, 



a type of lower marsupials, which, however, forms a sort of 

 placenta and thus approaches the higher mammals. 



assume that the progress from these marsupials 

 with primitive placentas toward that archetype 

 of Cernays and New Mexico took place during 

 the chalk period, that is to say, the last great 



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