PROFESSOR K. PEARSON AND DR. A. LEE ON 
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(see p. 90) with a certain degree of prepotency in the individual pairing. As we 
have already noted, collateral inheritance of the first degree alone considered 
will not enable us to discriminate between blended and exclusive inheritance. 
We note that the male in collateral inheritance predominates over the female, 
brothers being more alike than sisters in eye-colour, and brother and sister more 
alike than sister and sister. The mean value for inheritance in the same sex is, 
however, greater than the value for inheritance between opposite sexes (cf. p. 102). 
(c.) Collateral Heredity. Second Degree .—A very cursory inspection of the 
coefficients of correlation for the eight series of avuncular relationships shows us 
that it is quite impossible that the mean value should he '15 as required by the 
Galtonian Law. The average value of the avuncular correlation is '2650, and of 
the regression of nephew and niece on uncle or aunt is '2733. The probable error 
of the former result will not be more than '02, and of the latter something greater, 
. as the ratio of the variabilities is open to larger error. This mean value is accord¬ 
ingly, within the limits of errors of investigation, identical with the '25 to be expected 
on the theory of exclusive inheritance. It is a value which appears to be quite 
impossible on the theory of blended inheritance even with my generalised form of 
the ancestral law. 
We may draw several other important conclusions from our table of avuncular 
correlations:— 
(i.) Nephews are more closely related to both uncles and aunts than nieces are. 
This is true in each individual case, whether it be judged by correlation or regression. 
The mean correlations for uncles and for aunts are as '3081 to '2219 respectively. 
(ii.) Uncles are more closely related to nephews and nieces than aunts are. This 
is true for three out of the four individual cases; in the fourth case the difference 
is of the order of the probable error of the difference. The mean correlations ol 
nephews and nieces are as '2923 and '2377 respectively. 
(iii.) Paternal uncles and aunts are more closely correlated with their nieces and 
nephews than maternal uncles and aunts. The mean values are as '2719 to '2580. 
(iv.) Resemblance between individuals of the same sex is closer than between 
individuals of opposite sex. The mean values for the avuncular correlation in the 
same sex and in the opposite sex are respectively '2751 and '2549. 
(v.) Uncles are more closely related to nephews than aunts to nieces (mean 
correlations as '3455 to '2046). In fact, generally, we see a very considerable 
preponderance of heredity in the male line so far as these avuncular relations for 
and eye-colour, being characters of local races, or even families, and the husband seeking his wife in his 
own locality or kin; (ii.) in a possible correlation of homogamy and fertility. See ‘ Roy. Soc. Proc.,’ 
vol. 66, p. 28. Neither seem very satisfactory. Consciously or unconsciously, man and woman appear to 
select their own type in eye-colour and stature, until they are apparently more alike than such close blood 
relations as first cousins ! Until we know how far this correlation extends to other characters, it would, 
perhaps, be idle to draw conclusions as to its bearing on widely current views as to first cousin marriages. 
