SUMMARY OF STRUCTURES 473 



fundamental behavioral reactions. These details inckide the elements essen- 

 tial to vohmtary control of the extremities with especial reference to the 

 hand, the regulation of simultaneous movements of eyes, head and hand, the 

 increments of discriminative sensibility dependent upon manual ditlcrcntia- 

 tion, the increase of coordinative control of the musculature, the expansion of 

 the range of skilled movements, particularly manual performances, the 

 telencephalization in control of the functions of sight and hearing, and the 

 progressive development of I^inocular vision. 



