Page:Popular Science Monthly Volume 80.djvu/487

Rh important ones are forearm and span in Pearson's investigation. For the direct comparisons the resemblance is quite material, amounting to about + .200. Cross correlations are in general somewhat lower. Possibly the assortative mating is primarily for stature, while the resemblance for forearm and span arise merely because these are closely associated with stature. This point is not as certain, however, and deserves more attention.

For forty-eight families of East European (Russian) Jews living in New York City, Boas found an assortative mating for cephalic index (relative head breadth) of r = + .15 ± .10.

Lutz's interesting data on the inheritance of the method of clasping the hands show a positive sign in the correlation between the two parents, but it is so very small that no significance is to be attached to it.

Complexion and hair and eye color are conspicuous with stature in the popular superstition of "the charm of disparity" in human matings.

The calculation of the intensity of relationship in the case of a character which like eye color is not quantitatively measurable presents considerable difficulties, and the results vary with the method employed. From an analysis of Francis Galton's "Family Records," Pearson has deduced the following values: