MIGRATION IN THE OCULOMOTOR 



SOMATO- VISCERAL 



5 DAYS 



MIGRATION 



7 DAYS 



SEGREGATION 



DAYS 



FIG. 3. Diagrammatic frontal and transversal representation of the segregation of 

 the four nuclei of the Illrd nerve and of the migration of the two ventromedial 

 nuclei across the midline. Solid black, left oculomotor column; white, right 

 oculomotor column. a. b, c: stereographic views in a frontal plane, a', b', c': the 

 same process as viewed in transversal sections. 



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