A CONTRIBUTION TO THE STUDY OF THE SCOTTISH SKULL. 429 



I have compiled the foregoing table (L) showing the principal mean values for 

 the Scottish skull, with their standard deviations and coefficients of variation, along- 

 side the corresponding quantities for the male Tasmanian, which I have calculated 

 in many cases from the results in Buchner's (ll) paper, as well as the results for 

 50 unsexed Tasmanian skulls (Buchner) and the values for 90 Australian crania 

 (unsexed) calculated from the dioptrographic tracings shown in Berry and Robert- 

 son's atlas (40 and 40a). 



We observe that, while the Scottish skull is slightly more variable than the 

 Tasmanian in glabella-lambda length and in basi-bregmatic height in many of the 

 other chords, it is decidedly less variable — a result which is not in agreement with 

 our preconceived notions and with Pearson's statement that we get increased 

 variability as we pass from primitive or uncivilised to the civilised type. This was 

 alluded to before in speaking of the mean values of other cranial measurements and 

 their variation in primitive types and their comparison with this Scottish series. 



Falkenburger's Extension of Klaatsch's Method. 



Falkenburger (41), while pursuing an investigation into the application of 

 Klaatsch's craniotrigonometrical method to a series of deformed Peruvian and 

 Mexican skulls, discovered another relationship of certain lines that seemed to him to 

 occur very constantly, and he has pursued his investigations regarding this latter 

 point in skulls of individuals belonging to twelve different races, including the Negro, 

 Australian, and European, and the skulls of various anthropoids as well. He asserts 

 that the bregma-prosthion line stands at right angles to the basi-nasal line, and that 

 the greatest variation from this relationship is about 5°. There seems to hold, 

 consequently, he says, " almost a firmly fixed relationship in human skulls." He 

 states further that " the nasion-basion line is parallel to the bregma-lambda line," 

 which implies that the latter line is also perpendicular to the bregma-prosthion line. 

 Prognathism appeared to be without influence on the relationship. 



In the anthropoids the angle is always over 100°, i.e. falls outside the latitude of 

 human variation. In the chimpanzee the mean was 104°, in the orang-utan 108°, in 

 the gorilla 114°, and in one juvenile gorilla the angle was 99°. He is convinced that, 

 these very constant geometrical relations of the isolated points will be of great im- 

 portance in, and in fact will make easy, the reconstruction of ancient and probably 

 fragmentary or defective skulls. 



The point seems so interesting that, having median sagittal tracings of 100 male 

 skulls forming a homogeneous series, it seemed worth while to investigate what 

 relationship held between the lines stated in such a group. This I have done, and 

 the lines and figures are included in the series of 100 diagrams in which I have 

 applied Klaatsch's and Schwalbe's methods to the median sagittal tracings of 

 Scottish skulls. We can represent the lines alluded to by a rough sketch (fig. 14). 



