110 SMITHSONIAN INSTITUTION 



numerous examples of the Yuma, and other implements suggestive 

 of an older horizon than that of the recent Indians. 



Air. Jones took the writer to the places where he obtained the 

 various specimens comprising his extensive collection. Most of them 

 lie to the north of Mortlach, but some are to the west and the south. 

 The district is typically plains land, mainly flat, although there is 

 some slightly rolling terrain. The area north of the town, where the 

 best artifacts occur, suggests the former existence of a series of 

 shallow lakes or ponds, marshes, and bogs extending in a northwest 

 to southeast direction. These no doubt attracted game animals and 

 their shores would provide good camping places for the people hunt- 

 ing them, which probably accounts for the presence of the extensive 

 remains of both. Most of the bones scattered over the surface and 

 weathering out of the bottoms of the "blow-out" basins appear to 

 be from bison, although other smaller forms are present. Many of 

 the bison bones correspond in size to those from modern buffalo and 

 may represent that animal. Others are larger and may possibly be 

 from one of the extinct forms. To settle this question, it would be 

 necessary to obtain by excavation those portions of skeletons on which 

 species identification is based. Only a few points and fragments of 

 Folsom type, five or six at most, have been found in this region, but 

 there are literally hundreds of the Yuma and barbed forms. Most of 

 the specimens have been picked up from the surface, but a few have 

 been scratched out of the top of the exposed substratum. 



The constant association between Yuma and barbed types should 

 not be stressed too strongly at this time ; the latter could have been 

 in higher levels and dropped down to the top of the hard layer as the 

 overlying soil was blown away. Yet the writer dug one barbed 

 example from the substratum and found another partially embedded 

 in it. On the other hand, many Yuma pieces lying loose on the surface 

 have been picked up by collectors. In view of this, coupled with the 

 indications at Sundance, it seems that a somewhat later horizon is 

 indicated than is the case where points are predominantly of the 

 Folsom type. The Mortlach sites are important, however, because of 

 their size and the amount of material present in them and because 

 there is the possibility of finding places along the edges of the "blow- 

 outs" where excavation would reveal stratified deposits and produce 

 evidence on the sequence of the different forms of implements. They 

 extend the range of Folsom and Yuma artifacts well toward the north 

 along the supposed avenue of migration for peoples coming over from 

 Asia, and investigations in the Mortlach district may furnish much 

 needed data on the Yuma problem. 



