Page:Popular Science Monthly Volume 82.djvu/445

Rh interpretation. It is conceivable that a tribe may build up its culture by some independent inventions and by some borrowing from its neighbors, all of which may perhaps be revealed by the careful analysis of neighboring cultures and a comparative study of their traits. If we

 The shaded portions of this map mark the areas originally covered with trees. The true plains extend from north to south along the eastern border of the Rocky Mountains. On the west, trees are found on the sides of mountains; on the east, they stretch out into the plains along the margins of the streams. Reference to the tribal map shows how the typical group ranges in the open plains while the eastern agricultural village group lives in the partially forested belt. On the west the plateau group appears to range in the open stretches among the mountains.

apply this method to the Plains we find an easy line of approach. Some years ago, Mr. Mooney published his objective study of the ghost dance religion, a curious religious movement originating in one tribe and