88o 



MAN 



this light the expansion of the sensory regions ni the parietal lobe partieu- 

 larly related to the leg and foot, arm and hand becomes highly significant. 

 It seems most probable that sensory increment in these areas must be an 



FIG. 375. FUNCTIONAL LOCALIZATION OF THE BRAIN OUTLINED UPON THE 

 LEFT HEMISPHERE OF THE ENDOCRANTAL CAST OF PITHECANTHROPUS ERECTUS. 

 RESTORATION BY PROF. J. H. MCGREGOR. 



A, Auditory Area; F, Hifi;her Faculties Including Personality and Reason; 1 u. Fissure of Rolando; FS, Fissure 

 of Sylvius; o, Area of Skilled Movements; i>. Sensory Area (Touch and Muselc Joint Sense); s, Speech Area; 

 V, Visual Area; x. Area of Voluntary Motor ("ontrol. 



essential antecedent to any expansion in the reahn ol mori' highly C(jm|)Iex 

 motor performance. Kinesthetic sensibihty is a limdamental requisite to 

 all skilled acts. W ithoul it neither the motion lormula nor tlu' motor execu- 

 tion would be possible. For this reason the de\elopmcnt of new sensory 

 fields must have been closelx associated with the appearance ol new motor 

 territories, if they did not actually precede them. 



From the femur of i)ithecanthropus it is assumed that he stood and 

 walked erect much as do his modern successors. The assumption ol such 

 erect posture entailed an extensi\e sequence of adaptive modihcations, all 



