PHYSIOLOGICAL DOMINANCE 



107 



correspond to these different types of hcad^ and are 

 undoubtedly the fundamental factors in determining 

 general form and localization of the parts in the head"! 



54^ 



J ^:- 



CM.: 



^^c 



(H 



fC 



cm 



lu 



y ', 



n: 



545 



Figs. 54-56. — Different results of reconstitution in Planaria 

 dorotocephala: Fig, 54^, teratophthalmic animal; Fig. 54^, dilTercnt 

 forms of eyes in teratophthalmic animals; Fig. 55.4, B, teratomoqihic 

 forms; Fig. 56^, B, anophthalmia forms. 



As a matter of fact, these different forms are a more or 

 less arbitrary grouping of what is actually a graded scries 

 of forms from the normal head at one extreme to the 



^ See Child and McKie, "The Central Nervous System in Tera- 

 tophthalmic and Teratomorphic Forms of Planaria dorolocep/hila," 

 Biol. Bull., XXII, 191 1. 



