642 



Sir James Crichton-Browne 



[May 3, 



of the left hemisphere exceeded that of the right by at least the eighth 

 of an ounce ; and Broca also in 40 cases found the left hemisphere 

 the heavier. But then came other observers — Professor Wagner and 

 Dr. Thurnam — who found the right hemisphere the heavier ; and it 

 is to be noted that the excess claimed for the left by Dr. Boyd is 

 trifling — an eighth of an ounce, or 60 grains — and might well depend 

 upon methods of examination. 



I have weighed upwards of 2000 human brains, but I submit to 

 you the figures relating to only 400, as in that last series the weighings 

 were conducted with the most scrupulous care and after the hemi- 

 spheres had been stripped of their membranes (Fig. 16). You will 

 observe that in both sexes the right hemisphere is shghtly the heavier, 



Weight of Ceeebeal Hemispheres in 400 Cases. 



No. of Cases. 



Male 244 

 Female 156 



Whole Bram.j geiSsptre. Hemisphere. 



I 



grammes. 

 1334-7 

 1198-5 



Total 400 I 1281-6 



grammes. 

 580-7 

 521-1 



557-4 



grammes. 

 577-0 

 519-0 



554-4 



Weight of Lobes of Cerebral Hemispheres in 60 Cases. 



Lobe. 



Frontal Lobe 

 Parietal Lobe 

 Temporo Sphoidal Lobe 

 Occipital Lobe 



Fig. 16. 



but the difference is negligible, being only about 3 grammes or 45 

 grains -, and I feel sure that there is no difference in the weight of the 

 hemispheres corresponding with right and left-handedness. 



In 60 brains I weighed the different lobes of which the hemispheres 

 are composed. In the parietal lobe there is a very appreciable 

 difference in favour of the left side, but considering the difficulty of 

 dividing the lobes. I am not inclined to attach much importance to 

 that. 



Dr. Charlton Bastian has affirmed that the specific gravity of the 

 grey matter, or the active constituent of the brain, is higher in the 

 left than in the right hemisphere. The specific gravity varies greatly 

 in different regions of the brain and in different pathological conditions,. 



