INTERNAL STRUCTURE OF THE BRAIN STEM 1043 



poraneous record in the vast sphere of neokinesis which has been created 

 as the product of his hands. 



RELATION OF MAN TO APES 



These are the conclusions drawn from the accumulated evidences con- 

 cerning an evolutionary process in the brain of the primates. They recognize 

 the development of neokinesis in its several modifications as the keynote of 

 mammalian difTerentiation. They envision the process of selection and 

 evolution wherefjy this new type of motor acti\ity, seeking its fullest expres- 

 sion, at length found in the primates those structures from which to develop 

 the achievement of human neokinetic expansion. They take full account of 

 all of the intermediate simian steps in this process, but in no way denote or 

 imply a direct ancestral descent of man from any of the modern apes. In its 

 brain each one of the primates below man has, in its turn, borne the impress 

 of the effort to advance the cause of neokinesis. For this reason, if for no other 

 reason, each infrahuman primate gradation is important in the evolutionary 

 picture. It demonstrates the various attempts at progress showing in 

 what particulars they succeeded and also by just how much they fell 

 short of attaining the final goal. To consider any of the living apes the 

 possible ancestor of man is an inconsequential, trilling and incomplete view 

 of the situation which requires a much more extensive understanding of the 

 biological process for the complete appreciation of its significance. It does not 

 seem sufTicient to linger among the modern apes in search of our ancestors. 

 These animals belong to families totally divergent from man. They have 

 become most effectually arborealized, have ascended well up into the trees 

 where doubtless they will remain quite as unconcerned in the origin of man 

 as they are innocent of participation in it. 



\\ e are wise if we turn our attention not to these simians, but rather 

 to the generalized mammalian ancestors from which both apes and man 



