350 BUREAU OF AMERICAN ETHNOLOGY [bull. 52 



articular surface is shorter, broader, flatter, and less oblique. Their 

 outline is not reniform but more regularly elliptical and considerably 

 broader at the middle than in man, both relatively and absolutely. 

 The declivity downward and inward of the facets is much less accen- 

 tuated than in man — 'Svhich indicates a perfectly erect position." 



The inferior articular facets show fewer differences from the human 

 atlas than the superior ones. They are relatively much less oblique 

 and flatter than in man; "these are features correlated among them- 

 selves and with the size and position of the skull, proving that the 

 latter must have been of a proportionately larger size than in man 

 and perfectly vertical on the vertical column." 



Other features of the atlas to which considerable importance is 

 attached by Ameghino are the large size of the ventral parts of the 

 lateral masses; greater development of these masses in size and 

 weight; greater breadth of the superior articular facets, and their 

 advance on the canal of the bone. All these features ''indicate a 

 conformation destined to support in a vertical direction and in a 

 perfectly natural equilibrium, on the vertical column in erect posi- 

 tion, a skull heavier and consequently proportionately more vol- 

 uminous than that of a man." 



Reiteration of most of the above-mentioned points is found on 

 page 205 of the Ameghino memoir. 



In apostscript to his paper on the Tetraprothotno, Aiaeghmo informs 

 the reader that 'Hhis work was already completely finished and the 

 paper was ready for printing, when to-day, the 23d of September, I 

 received from my esteemed colleague, Dr. Lehmann-Nitsche, a 

 leaflet from the Eev. Mus. La Plata, xiv, 286-299, without cover, 

 without date, which bears the title of 'L'Atlas de Monte Hcrmoso.' 

 Under the circumstances scientists will find it incomprehensible that 

 the specimen is described at the same moment and under two dis- 

 tinct names by two authors. In order to obviate incorrect interpreta- 

 tion I am obliged to explain my position. 



' ' I have stated before ^ that I have asked Lehmann-Nitsche for the 

 specimen, which was not believed to be distinct from the corres- 

 ponding bone in present man. As soon as I saw it I recognized that 

 we were in the presence of man's precursor from Monte Ilermoso, of 

 which, as long as 20 years ago, I predicted the discovery. And 

 I have even had long verbal discussion with Messrs. Lehmann- 

 Nitsche and S. Roth to show them that the atlas in question was not 

 identical with that of man. Seeing the little that was made of it, I 

 requested permission to speak of it in my work on the femur, to which 

 M. Lehmann-Nitsche at once acceded." 



Subsequently Ameghino concludes: ''But all that is of only sec- 

 ondary importance. That which is truly exceedingly important, 



I Tetraprothomo, etc., p. 174. 



