674 GENERAL KEMARKS 



living body activity of function entails certain processes of growth, 

 whilst in rest the temporarily enlarged organ returns slowly to its 

 normal size, will be inclined to consider the clear lacunar space 

 which surrounds these large cells as eminently significant of their 

 activity as allowing room for increase of their dimensions. Nor 

 will any dispute as to whether these lacunar spaces are arte facta 

 due to action of hardening and contracting reagents or natural, 

 whether lymphatic or non-lymphatic, spaces affect this view. For 

 the contraction which, on the former of these views, the cell 

 undergoes in histological preparation may be very well taken as 

 reproducing after death a similar contraction which, ex hypothesi, 

 would accompany rest and abeyance of function in life. 



Coming in the third place to a consideration of the evidence 

 which processes of disease or other injury may give us for the con- 

 clusion that the parts of the brain anterior to the plane of the 

 parietal tubera are more active and important in function than 

 those situated posteriorly to it, I would refer the reader to the 

 instructive Plates iii-viii given by Dr. J. Crichton Browne in 

 his most valuable paper, already referred to, in the West Riding 

 Asylum Reports, vol. vi. 1876, on the pathology of the general 

 paralysis of the insane. In those plates a number of brains from such 

 patients are figured, and so coloured as to indicate the regions of 

 the brain upon which the stress of the disease has fallen. There is 

 in these ]}late8 scarcely an instance in tvhich a single patch of colour is 

 given on a sjjot situated posteriorly to the jissnre of Rolando. And 

 I submit that as it is but reasonable to suppose that the parts of any 

 organ which are found to be the most liable to suffer from irritation, 

 inflammation, and other morbid action are so because normally they 

 are the seats of habitual activity, this distribution of the signs of 

 disease over the area in question is of cardinal significance. 



In the last place, I will mention very briefly the indications 

 which the comparative anatomy of some of the various races of 

 mankind, and of the developing skull and brain in the human 

 species, as also the proportion of two segments of the parietal bone 

 anterior and posterior to the line of the primitive centre of ossifi- 

 cation, furnish to us in this investigation. 



tion of nitrogen, such increase did nevertheless take place when a certain interval had 

 elapsed after such exercise, explained (p. 55, 1, c.) this succession of phenomena by sug- 

 gesting that ' during action a muscle takes nitrogen and during rest gives it off,' or 

 that, ' in other words, the action of a muscle would seem from these experiments not to 

 be connected with disintegration but with formation; when it is in exercise the 

 muscle increases, when it is quiescent it lessens in bulk.' 



