592 DESCRIPTION OF FIGURES OF SKULLS. 



down of that region as it follows after the retreating brain, but the 

 brachy-cephalic form with retreating and low forehead is recognis- 

 able in quite young skulls both of early, as in the case of the ' Hesler- 

 ton Wold Hall Grave ' skull already described, and of present times. 

 Other senile changes are beginning to show themselves in this 

 skull in the way of loss of compactness of tissue and consequently 

 of gloss and smoothness on the external surface, in the very 

 extensive obliteration of sutures even in the external table of the 

 skull, a condition less frequently observed in brachy-cephalic than in 

 dolicho-cephalic skulls, and in the wearing down of the teeth to an 

 extent which, in an ill-nourished 1 individual, would have produced 

 alveolar abscesses. The conceptacula cerebetti are larger relatively 

 to the space occupied by the superior squama occipitis in this than 

 in most skulls, and the occipital protuberance is very considerably 



developed to fill up the void thus caused. In some cases an effusion of subarachnoid 

 fluid occupies the space as fast as it is formed, and in a case of a very aged man, 

 Dr. Holyoke of Salem, Massachusetts, a person known to be a centenarian, whose 

 body was examined after death, and whose symptoms of intra-cranial fluctuation 

 during life were recorded by himself (see Memoirs, p. 48 seqq., Boston, U. S. A., 1829), 

 this fluid must have been exuded in great abundance to occupy the space rendered 

 available by the shrinking of the brain. 



In other cases, as also to a considerable extent even when fluid is poured out in the 

 subarachnoid space, the inner table of the skull appears to secrete fresh laminae of bone, 

 and is found closely adherent, as in infancy, to the dura mater. In such cases the grooves 

 for the meningeal arteries appear to be deeply sunken into the substance of the skull, 

 having been in reality converted into deeper channels, or even tubes, by the upgrowth 

 of bone around them. This was the case in the body of a man supposed to be 106 

 years old examined by me, as recorded in the British and Foreign Medico-Chirurgical 

 Review, p 508, April 1863. A skull of a very aged person may under such circum- 

 stances attain a thickness of as much as 15 millimetres, forming thereby a striking 

 contrast to equally senile skulls in which the cranial walls may have been reduced 

 to paper-thinness or actual fenestration by atrophy. 



In a third class of cases the retreating brain is followed up by the skull walls ; and 

 especially in the frontal region is this concomitance of involution observable, both in 

 the living subject and in the skull, as has been noted by Lavater and Froriep, cited 

 by Cleland, Phil. Trans., p. 136, 1870. In some of these cases the inner table of the 

 skull will thicken simultaneously with the gradually sinking down of the cranial 

 vault. In a skull of an aged man, probably a Roman officer, eminently dolicho- 

 cephalic, forwarded to me by the Rev. W. Lukis, F.S.A., from Wath, near Ripon, 

 I find, coincidently with an extraordinary obliquity of the os frontis, two raised 

 arese, covering a space of a little more than an inch square on each side, as though 

 they were growing down into the space vacated by the atrophying frontal convolutions. 

 Some of the appearances which have been dwelt upon as characteristic of ' Neander- 

 thaloid' crania are, I arn well assured, to be ascribed to these purely physiological, 

 though senile, changes of form, and have absolutely no ethnological significance 

 whatever, except in so far as the texture of brachy-cephalic crania is usually stouter 

 and more resistent to gravitation changes than is that of the dolicho-cephalic, 

 amongst which most of the skulls just mentioned are to be classed. 



1 See J. Mummery, On the Relations of Dental Caries in Aboriginal Races. Trans. 

 Odont. Soc., Nov. 1869. 



