One thing is certain: in any such mixture, the surviving traits will be determined by competition between the lowest and most primitive elements and the specialized traits of Nordic man; his stature, his light colored eyes, his fair skin and light colored hair, his straight nose and his splendid fighting and moral qualities, will have little part in the resultant mixture. The “survival of the fittest” means the survival of the type best adapted to existing conditions of environment, which to-day are the tenement and factory, as in Colonial times they were the clearing of forests, fighting Indians, farming the fields and sailing the Seven Seas. From the point of view of race it were better described as the “survival of the unfit.” This review of the colonies of Europe would be discouraging were it not for the fact that thus far little attention has been paid to the suitability of a new country for the particular colonists who migrate there. The process of sending out colonists is as old as mankind itself and probably in the last analysis most of the chief races of the world, certainly most of the inhabitants of Europe, represent the descendants of successful colonists. Success in colonization depends on the selection of new lands and climatic conditions in harmony with the immemorial requirements of the incoming race. The adjustment of each race to its own peculiar habitat is based on thousands of years of rigid selection which cannot be safely ignored. A certain isolation and freedom from competition with other races, for some centuries at least, is also important, so that the colonists may become habituated to their new surroundings. The Americans have not been on the continent long enough to acquire this adjustment and consequently do not present as effective a resistance to competition with immigrants as did, let us say, the Italians when overrun by northern barbarians. As soon as a group of men migrate to new surroundings, climatic, social or industrial, a new form of selection arises and those not fitted to the new conditions die off at a greater rate than in their original home. This form of differential selection plays a large part in modern industrial centres and in large cities, where unsanitary conditions bear more heavily on the children of Nordics than on those of Alpines or Mediterraneans. _PART II_ EUROPEAN RACES IN HISTORY I EOLITHIC MAN Before considering the living populations of Europe we must give consideration to the extinct peoples that preceded them. The science of anthropology is very recent—in its present form less than fifty years old—but it has already revolutionized our knowledge of the past and extended prehistory so that it is now measured not by thousands but by tens of thousands of years.