The present little work, which is based chiefly upon data obtained while in charge of the mound explorations carried on by the United States Bureau of Ethnology, is presented to the public as indicative of the direction in which the more recent investigations in this line appear to lead.<br><br>I am under obligations to Major J. W. Powell for his kind permission to refer to the data obtained by the Bureau, bearing upon the questions discussed; but I must be held alone responsible for the views presented. The speculative theories advanced are, of course, but tentative, yet are believed by the author to accord more nearly with the facts ascertained than any suggestion, relating to the subject, which he has seen.