289 



§'Fig. 8. Anterior end of embryo 82 as seen from the right side and above. [The 

 balancer-forming region of a 3 mm embryo was transplanted on this embryo at the 

 3 mm stage!*! <^*- ^ anläge of anterior extremity, b normal balancer, b.t transplanted 

 balancer, e eye. fj 1, g 8 first and third external gills. ^ 30. 



transplanted ectoderm. The 

 balancers were however 

 never more than half nor- 

 mal size (Fig. 9), some being 

 only one-fourth normal size. 

 They developed several days 

 later than the normal and 

 dropped off about one week 

 later than the normal. The 



Fig. 9. Middle portion of 

 embryo 112 as seen from tlie left 

 and above. (The epithelium of 

 the balancer-forming region of a 

 3 mm embryo was transplanted 

 on this embryo at the 3 mm stage.) 



a. e anläge of anterior extremity. 



b. t transplanted balancer. X 25. 



a.e 



ae 



Anat. Adz. XXX.1. Autsätze. 



19 



