A CONTRIBUTION TO THE STUDY OF THE SCOTTISH SKULL. 



407 



of the frontal, parietal, and adjacent occipital triangles to the bases of these 

 triangles, and another perpendicular is dropped from the prosthion on the lambda- 

 glabella line, continued forwards, meeting the latter at the point Pr. 



The lengths of the various lines and chords composing the figure so devised 

 and the magnitudes of the various angles are carefully estimated and noted, and 

 an analysis of the whole system of lines and angles comprises what is known as 

 Klaatsch's " craniotrigonometrical method " for the study of the skull. In applying 

 the method to the group of 100 male skulls I have made use of the dioptrograph to 



Fig. 8.- 



-Outline of skull No. 13 of series K. This skull shows the highest value for the angle at the zentrum, i.e. 100" 

 Note the relatively long glabella bregma and relatively short glabella- basion chord. 



G. Glabella. 



Br. Bregma. 



L. Lambda. 



I. Lnion. 



Ba. Basion. 



P. Prosthion. 



Z. Zentrum. 



I, II, III, IV. Inner triangles. 



V. Frontal triangle. 



VI. Parietal triangle. 



VII. Chief occipital triangle. 



VIII. Adjacent occipital triangle. 



IX. Upper facial triangle. 



Br.Z.G. Zentral angle. 

 Br.G.Z. Upper glabella angle. 

 Br.G.Ba. Cranial glabella angle. 

 G.Br.L. Bregma angle. 

 G.Ba.L. Basion angle. 

 Br. L.Ba. Lambda angle. 



obtain the median sagittal tracings necessary, the skulls being previously carefully 

 oriented and centred. The various points required having been marked on the 

 tracings, the quadrilateral figure, the triangles and the various perpendiculars were 

 drawn as above described. The lengths of the various chords and their segments 

 were measured and the values of most of the angles noted. The angles of the 

 polygon were named by Klaatsch, each from the point where its apex lay, that 

 no confusion could arise — as does happen in Schwalbe's scheme, — and the position 

 of these angles will be readily understood from fig. 8. 



From a superficial examination of the method, one would think that the measure- 

 ments are so numerous and so varied that one should be able to make a minute and 

 detailed examination of the difference between any two skulls or skulls typical of 



