562 DESCRIPTION OF FIGURES OF SKULLS. 



unfit to be taken as a surface to measure from. The extreme 

 breadth therefore being always the extreme parietal breadth, it 

 has been unnecessary to have a separate entry for this as for the 

 corresponding- frontal and occipital diameters. 



The anterior margin of the occipital foramen has been frequently 

 so much injured in these ancient skulls as to render it impossible 

 to take their actual or ' absolute ' height from the plane of the fora- 

 men magnum. In these cases the so-called ' upright ' height of 

 Professors V. Baer i, His 2, and Ecker ^, taken by placing one arm 

 of the beam -compasses upon the posterior border of the occipital 

 foramen and at right angles to a vertical line passing from the 

 middle of the auditory foramen to the junction of the coronal and 

 sagittal sutures, and the other upon the most distant part of the 

 cranial vault, becomes of especial importance. This measurement 

 is, of course, somewhat greater than that of the ' actual ' or ' abso- 

 lute ' height as usually taken from the plane of the foramen mag- 

 num — a point to be borne in mind when we compare the height 

 and breadth of these skulls with those dimensions in other series. 



The imperfect state of the skulls has similarly rendered it im- 

 possible in many cases to take the measurements of the basi- 

 cranial axis, or of the cubical capacity. 



The minimum frontal width has been taken from a spot imme- 

 diately behind the external angular process of the frontal bone, and 

 below the temporal ridge on one side, to the corresponding spot 

 on the other. The maximum has been taken between two points 

 below the temporal ridge at the coronal suture. 



The maximum parietal width is, as stated above, given under 

 the head of ''Extreme Breadth ; ' the maximum occipital is taken 

 from the point ('asterion' of MM. Broca and Topinard) where the 

 occipital, parietal, and temporal bones of one side meet, to the cor- 

 responding point on the other ; i. e. between the two most distant 

 points of the lambdoid suture. 



It is not unusual to give a number of ' indices ' stating the pro- 

 portions existing between various measures of length in addition 

 to that usually called the ' Cephalic Index,' which gives the rela- 

 tion of the breadth of the calvaria to the length taken as 100. 

 Thus we have an index of the relation of the height to the length 

 and of the height to the breadth; a 'nasal index;' an 'orbital 



1 Zusammenkuiift einiger Anthropologen, p. 50, Leipzig, 1861. 



^ Crania Helvetica, p. 7, 1864. 



' Crania Gennanise Meridional. Occident., p. 3, 1865. 



