Among our American aborigines one trait stands out prominently, and that is the art of adapting themselves to existing and local conditions and environments. Perhaps no race so readily appreciated that it must depend entirely upon its own resources. We find, therefore, that it is immaterial whether the native Americans live in Maine or in Florida, in North Dakota, or Texas; they selected the most available materials. If the stone was easily chipped or of such consistency that it could be made use of, they adopted that stone for certain implements. If the stone was refractory and not easily chipped or worked, they did the best that they could with it. Therefore it is not always a criterion of poor workmanship nor does it indicate low degree of culture if the implements are crude and roughly and imperfectly made. It even means that there is no good material at hand and that the Indians selected the best they were able to secure and worked it out as well as they were able. Again, in certain sections implements made of good material are to be found, also of poor, coarse, local materials. Frequently the good material was transported from a distance. It may have come through trade or by means of conquest. That is immaterial. The point is that the natives naturally preferred materials more easily worked, but that they were not always able to obtain them. It is quite likely that few of the tribes were friendly in prehistoric times. The natives of a given river valley may have desired the better material to be found two or three hundred miles distant from their habitat, but because of the hostility of the nation living in that section where better material could be obtained, they were unable by either trade or conquest to obtain it, and had to be content with such unsatisfactory chert or other stone as occurred in their immediate locality. I think that this factor entered largely into prehistoric life. But if no suitable stone could be obtained, the Indians made use of bone or other substances. In several references to the Mandan village-sites in this work, the point was made that the Mandans used the large bones of the buffalo for a multitude of purposes. This was because suitable stone was scarce, and for the further reason that the bones were more easily worked and shaped than stone. In certain sections of the Mississippi Valley where materials of all kinds were in abundance many varieties of stone, shell, etc., were employed. The readiness with which the native adapted himself to conditions is shown in the house structure of the Indians. Those of cold climates lived in very different structures from those of the South. And the Plains Indians employed skin coverings, whereas the woods Indians made use of bark or of logs, and the Pacific Coast Indians used quantities of hewn boards. This is an interesting subject, and could be followed at considerable length did space permit. ART IN ANCIENT TIMES AND MODERN ART