PIGMENTATION IN OLD AMERICANS HRDLICKA. 



Eye color in individuals icith red hair. 



BOTH SEXES. 



461 



A little over one-third of the red-haired Old Americans have light 

 eyes. A little less than a half of these (46 per cent of the group or 

 17 per cent of the whole) are " light eyes — light reds," and to some- 

 where near that extent only may we assume red hairedness to be di- 

 rectly associated with blondness. In the rest of the cases with pure 

 light eyes the hair was medium to brownish- or chestnut-red. 



A large proportion of the eyes in the red haired are mixed. In 

 the whole series studied the proportion of mixed eyes was approxi- 

 mately 48 per cent; in the red haired it is 57 per cent, a plain ex- 

 cess for the latter. This excess, as well as the whole proportion of 

 mixed eyes in the red haired, points to the conclusion that red haired- 

 ness is strongly associated with mixture of blonds and brunets ; that, 

 in other words, it represents partial depigmentation or repigmenta- 

 tion. 



In a small per cent of our cases red hair was associated with eyes 

 that were pure medium brown. The hair ranged in these individuals 

 from light-red and salmon-red to brown-red and chestnut-red. As 

 the brown eye is believed to be dominant over the lights in mixtures, 

 the mixtures of types in these cases may have remained occluded; 

 but a partial depigmentation of the hair from any other cause might 

 possibly have been sufficient. We should scarcely be justified, in 

 other words, without much further inquiry into the subject, in regard- 

 ing red hair in the progeny of brunet parents as an absolute proof 

 of admixture into the family of either a red or blond haired outsider. 



The conclusions concerning red hair may be briefly summarized 

 as follows : 



(1) Red hair appears to be merely a form of depigmentation (or 

 partial repigmentation) . 



(2) In traces and minor degrees it is a far more common condi- 

 tion than generally appreciated. 



(3) In a large majority of cases it is connected with the mixture 

 of light with darker types of individuals. 



(4) In a minority of cases it may probably exist without mixture 

 as a variation in the direction of depigmentation (or partial repig- 

 mentation). 



