THE INHERITANCE OF FAMILY TRAITS 119 



1 44 44 On i 



so 5! 



Fig. 86. — Pedigree of chart of an European strain with night blindness 

 (black symbols). The rectangles indicate numerous normal individuals. 

 Two normal parents have only normal children. Nettleship, 1907, from 

 Gbuber and Rudin, 1911. 



