No. 508] HEREDITY OF HAIR COLOR IN MAN 



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Nr, nR, nn). Expectation in 12 offspring is 6.7 dark 

 brown or chestnut, 2.3 clear red, 2.3 pure brown or black 

 and .7 very light brown. This expectation is approxi- 

 mately realized in the totals. The matings of Table 

 IX, b, are of the order (NR, Nr, nR, nr) X (Nr). There 

 is actually a total of 51 individuals and expectation in 

 this case is 25.5 offspring with deep melanic or chestnut 

 hair and 25.5 offspring with pure melanic pigmentation 

 of some grade. No pure red should appear and none 

 does occur. The matings of Table X, b, are of the order 

 (NR, nR) X (nR). They should give an equality of off- 

 spring of the two types: NnRR (melanic pigmentation 

 with hypostatic red) and nnRR (red with little or no 

 black). The matings of Table X, c, are of the order 

 (NR, nR, Nr, nr) X (NR, nR, Nr, nr) . This should yield 

 in a total of 73 offspring 43.9 having dark melanic pig- 

 ment combined with (hypostatic) red; 14.6 with pure 

 brown of some grade; 14.6 with pure red and 4.9 with 

 sparse melanic pigmentation (yellow brown). The im- 

 portant proportional excess of the reds is explained m 

 the last paragraph. 



D. Is Inheritance of Haie Color at ale Blending and 



CAN IT BE SAID TO CONFORM TO GtALTON's Law? 



We have seen that, despite the difficulties offered by 

 change of hair color with age and by the masking ot 

 diffuse red pigment with brown granular pigment, in- 

 heritance in hair color can be brought into accord with 

 the ordinary formula for alternative inheritance. Hut 

 it may fairly be asked, since brown pigment is not a well- 

 defined unit character, whether hair color may not equally 

 conform to the blending type of inheritance If _ there 

 were blending ("as in human skin color"?) then the off- 

 spring of a dark and light should all be intermediate. 

 Table V is important in this inquiry. If blending oc- 

 curred the offspring of black and light brown shou d all 

 be brown (or light brown because of imma tunty) but 

 dark browns and a black occur; so in Table VI the y 

 blacks oppose the hypothesis; also in Tables VIII and 



