156 THE ROYAL SOCIETY OF CANADA 



II. The Calvarial Height 

 The study of the calvarial height as a criterion of cranial evolution 

 was found to yield rich results. At the outset it must be mentioned 

 that the calvarial height in all the skulls examined was taken as the 

 maximum distance between the glabella-inion line (the line AB in 

 Fig. 3) and the cranial vault. This line of course does not lie in a 

 horizontal plane, the latter being indicated by the line DE, which is, 

 however, to be taken as merely approximate for all the skulls repre- 

 sented in Fig. 3, as its position naturally varied in the different speci- 

 mens. It was obviously impossible to get one horizontal plane for all 

 four skulls, so that an average to suit all four had to be taken. How- 

 ever, the distance that really matters is that between the line AB and 

 the cranial roof. In Fig. 3 the four lines represent antero-posterior 

 cranial outlines in the mesial plane. They were all drawn to scale on 

 a standard glabella-inion base line. The lowest line represents the 

 skull of the Java man-ape, the next the Neanderthal skull, the third 

 an aboriginal Australian skull, and the fourth a modern European 

 skull. The third and fourth outlines did not absolutely coincide pos- 

 teriorly at all points but the fluctuation of the two outlines was so 

 slight that they have been represented there by the same line in order 

 to avoid confusion. In this relationship it is important to mention 

 that the occipital cranial arc of the Piltdown skull was found by 

 Smith Woodward practically to coincide with the corresponding part 

 of the cranial arch of a more recent British skull, thus once more 

 demonstrating the fact that the occipital cranial curve has apparently 

 undergone very slight evolutionary changes since the stage represented 

 by Piltdown man. The first point that strikes one about Fig. 3 is 

 the suggestive mental picture it presents of the remarkable strides 

 made by the developing brain, and the concomitant expansion of the 

 skull that has taken place in order to provide accommodation for its 

 growing cerebral contents from the stage represented by the Java 

 man-ape up to that of the highest development as exemplified by the 

 skull of modern white races. In preparing the outlines of the model- 

 reproductions of the skulls of fossil hominidae full use has been made 

 of the data in Dubois' numerous papers^ on the Java specimen, and 

 in Schwalbe's memoir- on the Neanderthal skull in checking the results. 

 In preparing Figs. 3, 5 & 6 the plan adopted was as follows : After 

 each cranial tracing was completed the glabella-occipital line was 

 drawn, and this was marked off into twenty equal parts. From 

 these points nineteen ordinates were drawn at right angles until they 

 reached the cranial outline. A standard glabella-occipital line^^of 



' op. cit. 

 " op. cit. 



