EYE FIELD OPERATIONS 



285 



4. In a somewhat similar manner, but with scissors, remove the entire eye 



ball of adult frogs or salamanders. Such hemorrhage as occurs is generally 

 not of any serious consequence (see diagram of adult eye). 



RANA PIPIENS 



LENS IMJCE. 



REGK3NS Of OPTIC VESCIX 

 »NLA3E INDICATED BEFORE 

 CLOSURE Of FOREBftAIN 



STAGE 13 - 14 



STAGE 17 

 (34 HRS. LATER) 



DEFECT EXPERIMENTS 



A. Excisions :* (See papers by Adelmann) 



1- Anura (stage #14) or Urodela (stage #15) 



a. Study the schematized diagram on the following page of a neurula showing 

 the limits of the eye field. Remove the ectoderm only from either area 

 "A" or area "B". 



b. Remove ectoderm and substrate (mesentoderm) from the same area 

 ("A" or "B") of another neurula. 



c. Remove ectoderm only from area "C". 



* See section on "Wound Healing" for details of post-operative care. 



