[CAMERON] THE HUMAN SKULL 179 



skull. The two are drawn to the same scale, the reduction being to the 

 extent of one half in each case. Note in the figure that the outline of 

 the microcephalic head very intimately corresponds to, though it is 

 very decidedly less than, that of the Java calvaria, so that it actually 

 fits inside the latter, being almost equidistant from it at nearly every 

 point. The maximum lengths were 18-1 cm. and 14-65 cm. It 

 should be noted moreover that at least 5 mm. would have to be taken 

 off the measurement of the model in front and behind in order to allow 

 for the thinkness of the scalp, and thus procure the approximate 

 glabella-inion length of the microcephalic skull which would then work 

 out at about 13-65 cm. It would therefore appear from the fore- 

 going facts that there can actually be found to exist at the present 

 day reversions of the modern human skull back to the stage of the 

 Java man-ape, and not only that, but even comparing unfavourably 

 both in dimensions and in capacity with his cranium. According to 

 the Darwinian theory this fact would contribute its testimony in 

 definitely fixing Pithecanthropus erectiis as an ancestral stage in the 

 evolution of man, and would thus assist in settling the great contro- 

 versy over the exact status of Java man, which has raged since the 

 discovery of his fossil remains twenty-five years ago. It is of interest 

 to compare other measurements in these two specimens. For in- 

 stance the maximum breadth of the microcephalic head was 11-2 cm, 

 which in its turn compared unfavourably with the maximum parietal 

 breadth of the Java calvaria, the latter being 13 • 3 cm. The minimum 

 post-orbital breadth of the microcephalic head was 9-4 cm., but if 

 due allowance were to be made for the thickness of the overlying 

 soft parts, the minimum post-orbital breadth of the skull itself must 

 also have been rather less than that of the Java calvaria which was 

 8-7 cm. 



A study of the jaws and the dentition in microcephaly will be 

 found to yield most valuable information regarding their evolution. 

 The teeth in this condition often present the most primitive characters, 

 so much so indeed in many cases that it is difficult to recognise the 

 different kinds and thus ascertain the dental formula. Moreover, in 

 many of these individuals some of the teeth never develop at all. 

 The effect of this defective dentition is reflected in the correspondingly 

 feeble degree of development of the jaws, which are consequently 

 both contracted and retracted, thus imparting the progressive back- 

 ward slope of the face from the nose downwards towards the chin, 

 and at the same time rendering the malar bones unduly prominent. 

 I should have liked to have studied the spheno-maxillary angle in the 

 specimen represented in Fig. 14. It could not have been more than 

 60°, an excessively low figure indeed. 



