36 Field Columbian Museum — Anthropology, Vol. II. 



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Norma Posterior. — All of the skulls are of pentagonal form, but 

 the outline is varied considerably in the different individuals by a 

 greater or less development of the parietal eminences, and by the 

 angle which the parietal bones make at the sagittal suture. In some 

 cases this is very open ; in others it is so sharp as to give a crest-like 

 appearance to the vertex. The sides of the crania are as a rule 

 nearly straight and parallel, so that in many cases the bi-asterionic 

 diameter nearly equals the maximum breadth diameter. The latter 

 diameter is invariably found through the parietal eminences. In only 

 one instance are the parietal eminences unusually prominent, and in 

 this skull the basilar synchondrosis is still open, although the third 

 molars have all erupted. The width of the base of the cranium is 

 remarkably uniform, averaging 98 mm. in the male series and 94 mm. 

 in the female series ; the range of variation for the entire series being 

 but 16 mm. Although the data are present in the table, I have not 

 computed the altitudinal index of breadth-height for each individual 

 skull ; but comparing the average of these two diameters for the 

 entire series we have a mean general breadth-height index of 100 ; in 

 other words the basi-bregmatic height and the maximum breadth are 

 equal. In one instance, however, the index is 108. The average 

 breadth-height index for Papuans is put by Topinard at 105. 



Norma Lateralis. — With but few exceptions the frontal develop- 

 ment is weak, the eminences are not strongly marked, and there is 

 consequently very little vertical development in the frontal bone. 

 The highest point of the vertex is situated to a considerable distance 

 behind bregma, while the vertex is, as a general rule, somewhat flat- 

 tened. The curve downwards from obelion to inion is very rapid, 

 with occasionally a depression, so that the curve is almost straight- 

 ened out. There is in all instances a well marked occipital develop- 

 ment between lambda and the external occipital protuberance, so that 

 in no case does the maximum diameter fall at the external occipital 

 protuberance or below it. In no case, furthermore, is there any pro- 

 nounced subiniac development, that portion of the occipital bone 

 being extremely shallow and giving but very little depth to the cere- 

 bellar fossae. 



The average basi-bregmatic height for the eight males is 131 

 mm.; the maximum height is 137 mm.; the minimum, 128 mm.; the 

 average for the seven females is 127 mm.; the maximum is 134 mm. ; 

 minimum, 120 mm. Combining these averages with the glabello- 

 occipital length we have a mean vertical or length-height index for 

 the males of 71 ; the average for the females is, as might be expected, 

 a trifle higher, 74. The highest vertical index is in a female skull, 



