392 THE EXTERNAL CONFIGURATION 



smaller than the right, though the measurements of the 

 organ, now that it has become flattened from its own weight, 

 and is slightly shrunk in consequence of its preservation 

 in spirits, do not show this so clearly as when it was in 

 the fresh condition.* Still even now the left hemisphere 

 is distinctly smaller than the right, both in length and 

 in breadth. The occipital lobes are as nearly equal in 

 length as they can be, but the left, internal perpendicular 

 fissure (owing to the smaller size of the frontal and 

 parietal lobes) now lies exactly f in. in front of that of the 

 right hemisphere. The left occipital lobe is, moreover, 

 distinctly narrower and less rounded externally than that 

 of the right side. The temporal lobes are of equal 

 length, but in regard to relative breadth they have been 

 too much altered by pressure to enable any opinion to be 



* This brain was removed on the third day after death, and was 

 not in a good condition for preservation. The measurements over 

 the vertex, then taken with great care by means of a narrow tape, 

 were as follows : 



Anterior extremity of Upper end of Fissure of Upper end of Perpendi- 

 Frohtal Lobe to upper end Rolando to upper end of cular Fissure to posterior 

 of Fissure -of Rolando. Perpendicular Fissure. extremity of Occipital Lo Lie. 



Inches. Inches. Inches. 



L. 4| 2f 2 



B. 5f 2| 2* 



Besides the special arrest of development met with in the left 

 hemisphere, the brain generally was distinctly shrunken, partly from 

 the effect of age, and partly from disease which had produced great 

 and general emaciation during the last twelve months of life. Prof. 

 De Morgan was well known to have had an exceptionally large head, 

 so that had it not been for age and the wasting above-mentioned his 

 brain would probably have weighed much more than it did, viz., 

 52f oz. The writer found the measurements of Prof. De Morgan's 

 head (almost free from hair) to be as follows : Circumference, 

 24J in. ; longitudinal measurement over vertex (root of nose to occi- 

 pital protuberance), 15f in.; transverse measurement over vertex 

 (from external auditory meatus to its fellow of opposite side), 15|in. 



