8 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. IO3 



initiate, and it is very much a question whether any of them should 

 be considered as belonging in the Yuma category. The uncertain 

 nature of the class was emphasized by the discussions at a conference 

 held at the Laboratory of Anthropology in Santa Fe, N. Mex., in 

 September 1941 (L. L. Ray, 1942; C, T. Hurst (The Editor), 1942), 

 when it was proposed that the Indeterminate group be dropped from 

 the Yuma series. Consensus was that as each of the forms became 

 established it could be named on the basis of its place of origin and 

 proper relationships. In view of this it probably is best, for the time 

 being, to refer to the present type as the San Jon point, adding the 

 proper qualifier when its affinities have been determined. 



The San Jon point was associated with the remains of a large bison, 

 probably the extinct taylorir The bones from this level are completely 

 fossilized, and in many cases articulated members were so firmly 

 mineralized that they were lifted from the earth as a unit. Numerous 

 examples of articulated feet and lower leg bones were found in 

 upright positions in the upper part of the silt or alluvium (pi. 3, fig. i ) . 

 They definitely suggested an animal wading out to drink, becoming 

 inextricably mired in ooze and perishing there. Perhaps the Indians, 

 certainly some of the carnivores in the area, preyed on the creatures 

 trapped in this fashion because in many cases bones from the upper 

 parts of the legs and the body were either entirely missing or else 

 were considerably scattered. 



The geologic age of this deposit is still to be established. At 

 another part of the site, however, a portion of a true Folsom point 

 was found weathering out of the same layer in association with frag- 

 ments of similarly fossilized bone. This, coupled with the fact that 

 a large bison is involved, points toward possible contemporaneity with 

 the Folsom horizon, one of the oldest thus far recognized in North 

 America and dated in the closing stage of the Pleistocene (Antevs, 

 1935 ', Bryan and Ray, 1940). But because the Folsom specimen was 

 not wholly in situ and represents only a single occurrence it can be 

 regarded merely as an indication. On the other hand the presence 

 of man-made objects with extinct bison remains and the occurrence 

 of mammoth bones, teeth, and tusk fragments in the same stratum 

 a few feet away, although no direct associations have thus far been 



- This material was identified by Dr. C. Lewis Gazin, assistant curator, 

 division of vertebrate paleontology, U. S. National Museum, who stated that 

 it obviously was from an extinct form closely approximating iaylori in size, 

 but because only lower jaws and Ics bones are available for study the species 

 cannot lie indicated with certainty. 



