RESEARCHES INTO ANTHROPOLOGICAL HEREDITY 189 



type.» It would be more correct, I suppose, to say that of the 

 offspring of two blue parents 69 have blue eyes, 6 bluish-gray or 

 gray eyes and 2 hazel coloured (light brown) eyes. 

 Granted that one of the parents is a recessive, and the other a 

 homozygote dominant, none of their offspring will have recessive 

 characters. Thus granted that one of the parents has homozygous 

 brown eyes (this is not to be seen of course) and the other of the 

 parents has blue eyes all their children will have brown eyes. 

 The authors believe to have a case in point, viz. the following. 



• Children Parents Grandparents 



a boy: brown 1 (hazel (brown 



a girl: brown ) | blue [brown 



blue 

 light blue 



, From this the conclusion is drawn that the eye colour is inherited 

 according to the Mendelian laws and that brown is dominant 

 to blue. t 



3. If one of the parents is a recessive and the other a heterozygous 

 dominant one (RR X DR = DR + RR + RR +DR) half of their 

 children will have the recessive character and the other half the 

 dominant one. 



The authors mean to have 6 couples of parents of that kind who 

 have 16 children with dark eyes and 9 children with light eyes. 

 The authors believe that the deficit of the light-eyed group is due 

 to the small number of cases investigated. — The result cannot 

 be said to strengthen the belief that the eye colour is inherited in 

 accord with the Mendelian laws. 



4. The authors' argumentation that gray (mixed) eyes are dominant 

 to blue seems even more uncertain. Even here they have to take 

 for granted that gray eyes really were blue instead of gray (the 

 Ma-family) in order to obtain the desired result in the particular 

 cases. The material is in fact too insufficient to allow any far 

 reaching conclusions. The authors draw, as is known, such con- 

 clusions. They are in short: 



a) Two blue parents will only have blue children. 



b) Two gray (mixed) parents will only have gray or blue children, 

 but not brown ones. 



c) Brown parents may have blue children as well as gray ones and 

 brown ones. 



