The terms of relationship used by the Tamils of Southern India and by the Seneca-Iroquois of New York State are to this day identical for more than two hundred different family relations. And among these East Indian tribes also, as among all American Indians, the relations arising out of the prevailing form of the family are not in keeping with the system of kinship. How can this be explained? In view of the important role played by kinship in the social order of all the savage and barbarian races, the significance of such a widespread system cannot be obliterated by phrases. A system that is generally accepted in America, that also exists in Asia among people of entirely different races, that is frequently found in a more or less modified form all over Africa and Australia, such a system requires a historical explanation and cannot be talked down, as was attempted, e. g., by McLennan. The terms father, child, brother, sister are more than mere honorary titles; they carry in their wake certain well-defined and very serious obligations, the aggregate of which comprises a very essential part of the social constitution of those nations. And the explanation was found. In the Sandwich Islands (Hawaii) there existed up to the first half of the nineteenth century a family form producing just such fathers and mothers, brothers and sisters, uncles and aunts, nephews and nieces, as the old Indo-American system of kinship. But how remarkable! The Hawaiian system of kinship again did not agree with the family form actually prevailing there. For there all the children of brothers and sisters, without any exception, are considered brothers and sisters, and regarded as the common children not only of their mother or her sisters, or their father and his brothers, but of all the brothers and sisters of their parents without distinction. While thus the American system of kinship presupposes an obsolete primitive form of the family, which is still actually existing in Hawaii, the Hawaiian system on the other hand points to a still more primitive form of the family, the actual existence of which cannot be proved any more, but which must have existed, because otherwise such a system of kinship could not have arisen. According to Morgan, the family is the active element; it is never stationary, but in progression from a lower to a higher form in the same measure in which society develops from a lower to a higher stage. But the systems of kinship are passive. Only in long intervals they register the progress made by the family in course of time, and only then are they radically changed, when the family has done so. "And," adds Marx, "it is the same with political, juridical, religious and philosophical systems in general." While the family keeps on growing, the system of kinship becomes ossified. The latter continues in this state and the family grows beyond it. With the same certainty which enabled Cuvier to conclude from some bones of