EYE FIELD OPERATIONS 



287 



EYE FIELD OPERATIONS 



NEURAL, FOLD ^^/^ '■> -:: 





.V; 



AS' 



ANURAN STAGE 13-14 



NEURAL OR 

 MEDULLARY PLATE 



NEURAL FOLD 



MESENCHYME 



SECTION THROUGH 

 PRESUMPTIVE FOREBRAIN 



OPTIC VESICLE 

 FIELD 



UENS FIELD 



VESICLE FIELD 

 LENS FIELD 



HOT NEEDLE 



HOT NEEDLE 



PRIMORDIA OF OPTICO - OCULAR APPARATUS 



TRANSPLANT: ARCHENTERIC ROOF 



STAGE 12 



INDUCTION OF EYE FIELD 



(REDRAWN FROM SPEMANN '38) 



