THEORY OF EVOLUTION 77 



X® 



X 



foci 



' '■A.rtNTj 



cy 



XX xo 



X 5^ '^i 



wxxxox® 



Fig. 38, A. Diagram illu.stratinjr inheritance of color blind- 

 ness in man • the iris of the color-blind eve is here black. 



XX 



IX X 



tea 



l"J'ARnfT3 



^m^^u XX m X 



Fig. 38, B. Recijirocal of cross in Fig. 38 a. 



barred. If these are inbred half of the dauoh- 

 ters are black and half are barred all of the 

 sons are barred. The grandmother has trans- 

 mitted her color to half of her granddaughters 

 but to none of her grandsons. 



