place until after this period. Thus, Fanny Burney married at forty-one, Mrs. Browning at forty, Charlotte Brontë at thirty-eight, while George Eliot's relationship with Lewes was formed at about the age of thirty-six; these names include the most eminent English women of letters. It would thus appear that there is a tendency for the years of greatest reproductive activity to be reserved for intellectual development, by accelerating or retarding the disturbing emotional and practical influences of real life. This tendency might still be beneficial, even when the best work was not actually accomplished until after a late marriage. We have now to consider the fertility of the marriages formed by men of preeminent intellectual ability. Lombroso and others have insisted on the tendency to sterility among men of genius, but have always been content merely to cite a few cases in proof. This method can at the most raise merely a presumption in favor of the dictum laid down. The present investigation, covering a very large group of men of the highest intellectual eminence, furnishes more conclusive evidence as to the actual facts. It confirms only to a limited extent the belief in the relative sterility of men of genius, though we have to remember the very high mean age of the individuals we are considering. The married men of intellectual ability in our list number 587; of these, 448 had children; seventy-six are definitely stated by the national biographer not to have had children; sixty-three cases remain in which the point is passed without mention, or in which it is stated that the marriage was not fruitful, but that there were illegitimate children. It appears, so far as I can judge, that in the majority of the sixty-three doubtful cases, there were really no legitimate children; this has most often been found to be the case when I have checked the national biographer by other sources of information. In a certain proportion of cases, however, the facts regarding children are not known, and in others the children have apparently been ignored. We may probably conclude that nearly two-thirds of these sixty-three doubtful cases were really unfruitful. (I may add that, even if we exclude the doubtful cases altogether, the proportion of unfruitful marriages remains very abnormally large.) We then find that about 20 per cent, of the marriages of British men of genius have been unfruitful. In this case we have not much difficulty in obtaining a normal standard of comparison. Karl Pearson, manipulating the data furnished by Howard Collins, has found that during the past century among the middle and upper classes chiefly of British race, or belonging to the United States—a class fairly comparable to those in the present group—the total sterility is about 12 or 13 per cent., rather less than half of this (t. e., about 6 per cent.) being due to what is termed 'natural sterility'; while the remainder (i. e., 6 or 7 per cent.) must be set down to artificial restraints on reproduction. If, again, we turn to New Zealand, where
