NO. lO NEBRASKA ARCHEOLOGY STRONG 53 



300 implements of apparent human origin from the PHocene beds in 

 western Nebraska were described. According to this account the 

 implements were of 40 dilTerent types, of which certain forms found 

 counterparts in known artifacts from other archeological sites in North 

 America. Since the materials employed in the former were the bones of 

 extinct species of animals, and the artifacts came from the same 

 general beds as the " HcspcropitJiccus '" tooth, the presumption that 

 the two finds w-erc associated seemed logical. Such a presumption 

 involved not only the occurrence of the hitherto unknown American 

 anthropoid in the Pliocene of Nebraska but also the fact that he was 

 already a tool-using animal with a well-developed material culture. 

 When it is realized that the oldest human fossils yet discovered in the 

 Old World are regarded as either early Pleistocene or very late Plio- 

 cene in geologic age and that no traces of a complex material culture 

 have been found associated with them, the extremely radical implica- 

 tions of the above report become apparent. These implications were 

 partially confirmed in an article published shortly thereafter by 

 Osborn," in which both Hesperopitliecus and the fossil Ijone imple- 

 ments were entered on a chart showing the development of man 

 through the Pliocene, Pleistocene, and Recent periods. Both were 

 entered in the Middle Pliocene portion of the chart as the " most 

 ancient evidence of man," but surmounted by a question mark. 



This question mark was soon fated to grow to such proportions that 

 it has completely overshadowed the above tentative conclusions. In 

 Science for Deceml>er 16, 1927, Gregory published an article entitled 

 " Hesi')eropithecus Apparently Not an Ape nor a Man " ( 1927, pp. 579- 

 581), in which he reviewed the earlier facts of the case and stated, on 

 the basis of the more adequate material obtained from the Snake Creek 

 beds by Thomson, his doubt regarding the correctness of his former 

 identification of the original tooth as a primate. Rather it would 

 appear that the tooth bore a more specific resemblance to many simi- 

 larly worn-down premolar teeth of a species of Prosfheiiiiops, an 

 extinct genus related to the modern peccaries. While there are certain 

 details in which the " Hesperopitliecus " tooth difi:"ers from those of 

 ProstJie}inops in general it agrees with almost every conspicuous char- 

 acteristic in that type. Many of the Prosfliciiiwps teeth had been 

 found which resembled the " Hesperopithecus " s])ecimen except that 

 their crowns were less worn. He concludes : " Thus it seems to me far 

 more probable that we were formerly deceived by the resemblance of 

 the much worn type to the equally worn chimpanzee molars than that 



'^ Osborn, 1927, tig. i, p. 482. See also Vosy-Bourbon, 1929, p. 408, for a later 

 foreign notice. 



