My Geological and archaeological studies in the Valley of Mexico, which I have carried out since the end of 1945 under the auspices and with the aid of the Viking Fund, Inc. of New York, were rewarded on February 22 of this year (1947) by an extraordinary find of human skeletal remains in the Upper Pleistocene Bercerra formation at Tepexpan, in the State of Mexico. So far the quest for genuine fossil human remains in North America has been a tantalizing venture because of the incomplete state of preservation and the uncertainty of dating. In this respect the Tepexpan find would seem to meet many of the requirements necessary for assigning it to a known geological formation dating back to the close of the Ice Age. Moreover, the formation in which the human fossil was excavated has yielded at several other localities artifacts which must be regarded as more or less contemporary.