d sexual selection, as evidenced by a
comparison of married couples.[180] Karl Pearson, however, in part making
use of a large body of data obtained by Galton, referring to stature and
eye-color, has reached the conclusion that sexual selection ultimately
results in a marked degree of parity so far as these characters are
concerned.[181] As regards stature, he is unable to find evidence of what
he terms "preferential mating"; that is to say, it does not appear that
any preconceived ideals concerning the desirability of tallness in sexual
mates leads to any perceptibly greater tallness of the chosen mate;
husbands are not taller than men in general, nor wives than women in
general. In regard to eye-color, however, there appeared to be evidence of
preferential mating. Husbands are very decidedly fairer than men in
general, and though there is no such marked difference in women, wives are
also somewhat fairer than women in general. As regards "assortative
mating" as it is termed by Pearson,--the tendency to parity or to
disparity between husbands and wives,--the result were in both cases
decisive. Tall men marry women who are somewhat above the average in
height; short men marry women who are somewhat below the average, so that
husband and wife resemble each other in stature as closely as uncle and
niece. As regards eye-color there is also a tendency for like to marry
like; the light-eyed men tend to marry light-eyed women more often than
dark-eyed women; the dark-eyed men tend to marry dark-eyed women more
often than light-eyed. There remains, however, a very considerable
difference in the eye-color of husband and wife; in the 774 couples dealt
with by Pearson there are 333 dark-eyed women to only 251 dark-eyed men,
and 523 light-eyed men to only 441 light-eyed women. The women in the
English population are darker-eyed than the men;[182] but the difference
is scarcely so great as this; so that even if wives are not so dark-eyed
as women generally it would appear that the ideal admiration for the
dark-eyed may still to some extent make itself felt in actual mating.

While we have to recognize that the modification and even total inhibition
of sexual ideals in the process of actual mating is largely due to psychic
causes, such causes do not appear to cover the whole of the phenomena.
Undoubtedly they count for much, and the man or the woman who, from
whatever causes, has constituted a sexual ideal with certain characters
may