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HALFDAN BRYN 



in the same manner, or whether for instance there is any difference 

 with regard to the mode of inheritance between Hght mixed eyes ha- 

 ving only a well defined narrow brown ring around the pupil, and 

 dark mixed eyes, where the blue tint hardly perceivable may be traced 

 in the most peripheral parts of iris. In my opinion the material is not 

 sufficient. But it suggests that there is a difference. I have only 3 

 families where both parents have light mixed eyes. In these 3 families 

 all the children had light mixed eyes of one and the same type — a 

 narrow, but well defined brown ring around the pupil. In these 

 cases no segregation in plain blue children and plain brown ones 

 took place. 



TABLE 4. 



The inheritance of mixed eyes. 



In this table the eye types are thus marked: Plain blue eyes or bluish gray 

 eyes without brownish pigmental. Plain gray eyes without brownish pigment 

 = 2. Light mixed eyes (blue eyes with a narrow brown ring) := 3. Dark mixed 

 ej'es (brown eyes, a blue tint in the periphery) = 4. Plain brown eyes = 5. 



So it may not be considered inconceivable to find this type as a 

 biotype (Verschmelzungsbiotypus) in Selbu and Tydalen. The rela- 

 tion of these light mixed eyes to plain blue eyes when bred is also 

 striking. This is found in 16 couples with 39 children. 24 of these 

 children have plain blue eyes, 12 light mixed eyes, 2 dark mixed eyes 



