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1910 - 11 ] The Inheritance of Complex Growth Forms. 
These, however, are not what are found. The progression derived by 
Pearson from direct observation for the same relationship, is* 
•5, -33, -22, -15. 
As before observed, these values arise on a Mendelian basis with dominance 
if a coefficient of assortive mating of r—' 25 be assumed. In the case of 
stature in man this is even exceeded. Professor Pearson finds that for this 
quality r = ‘ 28, so that although for purposes of calculation it is assumed 
that r — ' 25, this value is in defect. With the grouping assumed in this 
paper, the coefficient of correlation between parent and child without 
assortive mating is found to be r = '%, exactly as in the case considered by 
Professor Pearson, f In this case, however, the increase produced by the 
degree of assortive mating considered is not so large as in that where 
dominance is assumed to come exclusively from one side. The coefficient 
of correlation between parent and offspring is raised from r=‘ 3 to r = * 46, 
somewhat in defect of the value r = '5 found from observation. It is, 
however, in the highest degree improbable that pure dominance regulates 
inheritance. Blending, as already remarked, must also occur, and as a 
like coefficient of assortive mating must be held to apply in this case, the 
increase in the value of the coefficient to the neighbourhood of r — % 5 is 
almost a necessity, since for pure blended inheritance the correlation of 
parent and offspring is in the neighbourhood of r — *6 when the coefficient 
of assortive mating is given by r = 25. 
To settle this question, inquiries into the constitution of races will 
require to be made, but I think that I have shown that there is nothing 
necessarily antagonistic between the evidence advanced by the biometricians 
and the Mendelian theory. 
Conclusions. 
(1) If the inheritance of stature depends upon a Mendelian mechanism, 
then the distribution of the population as regards height will be that 
which is actually found, namely, a distribution closely represented by the 
normal curve. 
(2) There is nothing in the values of the coefficients of inheritance 
found by Sir Francis Galton and Professor Pearson which cannot be 
explained on the basis of Mendelian inheritance. 
Note I. 
Let assumed symmetrical, represent the crude distribution of x as 
indicated above, and let each portion of the population vary according to 
* Biometrilca, vol. ii. p. 373. + Trans. Roy. Soc., 1903, p. 53. 
