A CONTRIBUTION TO THE STUDY OF THE SCOTTISH SKULL. 437 



'753 for the same values. The difference in the Scottish result from that in the 

 Europeans of Berry and Robertson's papers may be due to the fact that the values 

 of the latter were sometimes obtained from one specimen, and that the type compared 

 was brachycephalic, not dolichocephalic. 



I do not purpose here to follow Berry and Robertson's biometrical methods 

 further. I am prepared to admit that, taking the mean value in a sufficiently large 

 series of skulls of the same form and type as, for instance, the Australian, Tasmanian, 

 and West Scottish, the summation of all these characters of the vault in the manner 

 suggested may result in a reasonable order. 



The difficulty is that there are two types both on the highest evolutionary plane 

 — one long and narrow, the other short and broad ; and even though the calvarial 

 height remain the same, many of the characters of the vault may be different. 



Before a proper comparison can be instituted between different types it is 

 essential that large series should be available to get representative mean values. 



5. Median Sagittal Section of Skull. 



There is universal agreement amongst craniologists as to the value to be attached 

 to the study of the skull after it has been sectionised in the median sagittal plane ; 

 not only that such a view shows us essential differences between the human skull 

 and that of lower forms, but enables us to utilise certain important characters in the 

 comparison of skulls of different races which cannot be made use of by the ordinary 

 methods of measurement, as they only become obvious in the sectional diagram. 



Amongst those who have recognised the importance of this method of comparing 

 skulls are Huxley (51), and we recall his well-known "dictum" on the subject; 

 Turner in his " Challenger" Reports and various memoirs ; Cleland ; and Bolk (42). 



The skulls having been sawn, the difficulty was to get the exact outline of their 

 mesial section quickly transferred to paper. 



1 placed a thick layer of blotting paper on the surface of a slightly yielding pad 

 and placed the sheet of paper with the carbon paper on its upper surface on the 

 blotting paper. The skull cut surface was then applied to the carbon paper and 

 firm pressure exerted from above, with the result that an accurate impression of the 

 cut surface of the skull was left on the paper underneath. This was then outlined 

 in ink. 



One skull was not bisected, as the spheno-ethmoidal region was seen to be 

 defective ; in another, after being sawn, the same region was found to be deficient, 

 and the values for these skulls are not included in the results. This left me 98 skulls 

 for investigation, and the following results are based on the measurements obtained 

 from these. 



I decided first of all to measure and examine the mean value and variability of 

 certain angles measurable on the mesial section which are regarded as of morpho- 



