326 BUEEAU OF AMERICAN ETHNOLOGY [bull. 52 



ANTHROPOLOGIC CHARACTERISTICS 



In a detailed study of the specimen it soon became plain that 

 almost the entire original description by Ameghino had miscarried 

 by reason of the fragment having been placed and considered in a 

 wrong position. It had been viewed not in the indispensable 

 approximation to either of the standard skull positions recog- 

 nized in anthropology, but just as it lay on some pedestal or on the 

 table. This accidental and faulty position of the fragment had 

 changed the inclination of the plane of the articular surface for the 

 nasal bones, had made the glabella and especially the roofs of the 

 orbits look more forward, had changed a supraglabellar to a post- 

 glabellar space and made the same look nearly upward, had caused 

 the forehead to appear much lower than it is and had given 

 the sagittal line a slope backward different from that which it 

 possesses. All these results of faulty orientation combined have 

 helped to make the specimen look extraordinary and primitive, even 

 unhuman. 



The first step in the writer's examination of the fragment con- 

 sisted in placing it in the position it would occupy in the alveolo- 

 condylian plane of the skull. But as this could not be accomplished 

 directly, owing to the defective nature of the specimen, an entire 

 skull was looked for having a nearty related form and the same 

 nasion-bregma diameter, which could therefore be utilized with pro- 

 priety as a model. Such a specimen was found in No. 52, a modern 

 male Indian cranium of unknown provenience, in the Museo Na- 

 cional, Buenos Aires, which not merely presents a frontal of the same 

 length as the Biprothomo fragment, but resembles the latter also in 

 other particulars. This specimen was brought into the alveolo- 

 condylian plane, the inclination of the nasion-bregma axis was ascer- 

 tained and then the Diprothomo specimen was placed so that its 

 nasion-bregma axis formed the same angle as thQ model, with the 

 horizontal (pis. 49, 50). 



The results of the observations made were as follows: 



The nasion was found to be 6 mm. beneath the horizontal line 

 connecting the uppermost parts of the borders of the orbits. 



The location of the point is undoubtedly high, but among 78 more 

 or less modern Indian crania of the Museo Nacional collection, which 

 were examined and measured for comparison, there were 9 in 

 which its situation was equally high or even higher. The list below 

 shows the distance of the nasion in these skulls from the line connect- 

 ing the highest points on the superior border of the orbits (outside 

 of the orbital foramina or canals) : 



mm. 



Diprothomo 6. 



No. 3. Patagonian, male 4. 



No. 25. Calchaqui, male 4. 5 



No. 52. Indian, tribe not stated, male 4. 5 



