ing tribes living along the fringe to the eastern forested area. We have then rather good evidence that cultural transitions went on in both directions within the Plains area. On one side were the typical non-agricultural tribes in the midst of buffalo, on the other were the forest tribes living in fertile valleys amid the trees with their small fields of maize; between them along the Mississippi, the lower Missouri, the Illinois, etc., were interspersed prairies and woodlands. Naturally, the people in this middle ground might take to alternating in buffalo hunting and planting, finally some going over entirely to the one or the other. Thus we had, no doubt for many decades, a shifting of culture influences, now in one direction, now in the other, and while we have here no evidence of a fixed direction of development we do have what may be taken as a typical example of how a people develop culture. In general, we believe that the facts warrant the assumption that the typical Plains culture was developed in the heart of the area and was the composite result of independent invention and the adaptation of intrusive cultural traits from the east, south and west.