158 



CHARLES R. STOCKAKD AND A. L. JOHXSOX 



for this measurement but is more than half way down the 

 slope in the zygomatic series. There is no correlation between 

 the width of the head at the zygomatic arch and the broad- 

 ness of the cranium, and this lack of correlation is quite 

 independent of differences in skull size. 



60 1 



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 2o- 



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Text-figure .' 

 figure 2. 



Sequence A. Cranial width. Same ski 



equence as text- 



One other transverse cranial measurement, the least frontal 

 width (pi. 35, fig. 1, E) has been taken. The values for this 

 measurement are represented in text-figure 4. The least 

 frontal width ranges from 49 to 27 mm, a proportion of 

 about 7 :4. Again there is not the slightest correlation between 

 this width and that of the zygomatic arch. 



The series of interorbital widths (pi. 35, fig. 1, D) is indi- 

 cated in text-figure 5. These range from 57 to 22 mm or 

 about as 5 :2. As might be anticipated, there is here a fair 

 degree of accord with the zygomatic widths although many 

 individual irregularities occur. The mode of divergence of 

 the zygomatic process of the maxillary bone has an effect 

 on both the zygomatic widtli and the interorbital width and 

 this no doubt underlies to some extent the accord between 

 these two measurements. 



