loess, various concretionary deposits, burnt earth and scoria that were 

 supposed to be of ancient human origin, and other articles, were 

 gathered and brought back with us for further investigation in our 

 laboratories. 



After the return of the expedition to Washington the gathered 

 data and specimens were subjected to considerable further studies and 

 comparison. A large amount of recent human skeletal material from 

 South America was examined by the writer. The archeology was 

 taken up by Professor W. H. Holmes of the U. S. National-Museum; 

 the petrology by Messrs. T. E. Wright and C. N. Fenner of the 

 Geophysical Laboratory, Carnegie Institution; the shell material was 

 turned over for identification to Dr. Wm. H. Ball of the U. S. 

 Geological Survey, and chemical examinations of numerous bones 

 were conducted under the direction of F. W. Clarke of the same 

 institution. 



The results of our field work and those of the researches in our 

 laboratories fail, regrettably, to sustain the contentions of the South 

 American men of science, even of the more cautious of them, such 

 as Roth and Lehmann-Nitsche. They are, in brief, without exception 

 adverse to the theory of the existence of early man and his precursors 

 on the southern continent. Anthropology, geology, archeology, the 

 study of the burnt earths and scoriae, that of the shells which should 

 have established the great age of some of the strata, and the chemistry 

 of the bones, all speak independently and forcibly against the assumed 

 existence of ancient human or of any prehuman forms in South 

 America, The evidence obtained attests nothing more than the 

 presence in the south, as similar evidence has formerly in the north, 

 of the already differentiated and relatively modern American Indian. 



The bibliography of the subject, the historic data, the details 

 which led to the above conclusions, will be found in the volume 

 recently published by the Bureau of American Ethnology, referred to 

 on the first page of this paper, and need not be here repeated. The 

 only question which requires to be approached, at least, in this place 

 is that of the causes which have led to the remarkable conclusions 

 concerning the antiquity of man in South America reached by 

 Ameghino and others who have occupied themselves with the problem. 

 How has it come about that a number of investigators, including 

 Ameghino, the foremost exponent of South American paleontology, have 

 arrived at, maintained and even strenuously defended conclusions^ 



