The first series of serious observations tending to confirm the result reached by the genius of Leonardo da Vinci and to show that sexual selection results in the pairing of like rather than of unlike persons was made by Hermann Fol, the embryologist.[179] He set out with the popular notion that married people end by resembling each other, but when at Nice, which is visited by many young married couples on their honeymoons, he was struck by the resemblances already existing immediately after marriage. In order to test the matter he obtained the photographs of 251 young and old married couples not personally known to him. The results were as follows: RESEMBLANCES NONRESEMBLANCES COUPLES. (PERCENTAGE). (PERCENTAGE). TOTAL. Young.............. 132, about 66,66 66, about 33.33 198 Old ................ 38, about 71.70 15, about 28.30 53 He concluded that in the immense majority of marriages of inclination the contracting parties are attracted by similarities, and not by dissimilarities, and that, consequently, the resemblances between aged married couples are not acquired during conjugal life. Although Fol's results were not obtained by good methods, and do not cover definite points like stature and eye-color, they represented the conclusions of a highly skilled and acute observer and have since been amply confirmed. Galton could not find that the average results from a fairly large number of cases indicated that stature, eye-color, or other personal characteristics notably influenced 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