13 



ronment than upon time. Actually no perceptibly mineralized human 

 bones were seen by the Expedition in Argentina which were not 

 regarded by at least some of the local scientists as geologically an- 

 cient. Yet along the coast and in other places, on or near the sur- 

 face of the ground, lay many bones of domestic and other animals 

 of living species showing plainly various phases of "fossilization." 

 Really no bones from burials or inclusions in the Pampean deposits 

 "were met with that were not more or less mineralized, which is 

 easily explainable by the high percentage of calcareous and other 

 contents favoring "fossilization" held by the formation. 



The results of lack of experience in anthropological matters mani- 

 fested itself especially and painfully in the case of the "Diprothonio." 

 This form is represented by a frontal bone with a portion of the 

 parietals. The fragment was described not in the position which it 

 would occupy in a normally poised skull, but in that which it 

 assumed when laid on the table. This error, already well pointed out 

 by Schwalbe, was responsible for the creation of a genus of human 

 ancestors. 



The description of various specimens extended to, and made much 

 use of minute details, which are known to be of little or no anthro- 

 pological significance. In the cases of the Diprothomo and Tetra- 

 prothomo, as published by Ameghino, there are page upon page of 

 minutia through which even a trained anatomist wades with diffi 

 culty and which only obscure the true character of the specimens. 



The Monte Hermoso atlas, notwithstanding its doubtful origin and 

 the fact that, while not exactly common in form, it in every respect 

 is well within the range of variation of the same bone in the pre- 

 historic and probably even in the historic American Indian, was at 

 the same time being described as a part of the Tetraprothomo by 

 Ameghino and as a representative of a new Tertiary species of Ameri- 

 can man by Lehmann-Nitsche. 



Finally, as to the part mere theory played in these connections, 

 it is sufficient to point to the Ameghino's hypothesis about the various 

 "Precursors," and to his system of human descent and migration. 

 He derived the whole family from certain little primitive forms in South 

 America and peopled that continent with hitherto unsuspected species 

 of man and genera of precursors. He asserted that Africa and Oceania 

 were peopled by the descendants of a far distant precursor of man, 

 the Triprothomo; and he assumed that a later spread of man from 



