538 PROFESSOR MARSHALL ON THE BRAIN OF A BTTSHWOMAN ; AND 
indicates a very great degree of simplicity in the idiots’ brains. The bent convolution 
itself, also, is very simple and symmetrical. The two correspond, in both brains, to the 
most prominent parts of the parietal regions, and therefore to the widest part of the cere- 
brum, lying beneath the parietal eminences of the skull ; whereas in the perfect human 
brain it is the large and peculiar supramarginal lobule which occupies this post. 
The temporal convolutions (Plates XXI. & XXII. figs. 12 & 16) in both the idiots’ 
brains are simple in form, but large, and, indeed, in the female enormously developed. On 
both sides in the latter (Plate XXI. fig. 12) the middle temporal (&- b ) is the largest, the 
upper temporal or inframarginal (7-7) is the next in size, whilst the lower temporal (9-9) 
is rather more moderate in size. In the idiot boy (Plate XXII. fig. 16), on both sides, 
the middle temporal is still the largest, but the difference is not so marked. In both 
brains there is a want of symmetry in the convolutions of the two sides, those of the 
right side being bounded by more tortuous furrows, and having a few secondary sulci ; 
whilst on the left side they are nearly smooth. They are all continued backwards into 
the diminutive occipital lobe by simple, but, in the woman, serpentine connecting con- 
volutions. 
The occipital lobe is so small in both idiots, and so slightly marked by rudimentary 
sulci, that its three ordinary stages or rows (Plates XXI. &XXII. figs. 12, 14 & 16, 10 , 11 , 12 ) 
can scarcely be separately recognized ; but it may be described as consisting of a shallow, 
smooth edge of cerebral substance, so blended on the outer side with the second, third, 
ancl lowest external connecting convolutions, and on its under side with the internal tem- 
poral, as almost to lose its identity in those aspects, and to appear like a mere narrow 
continuation backwards of the temporal lobe itself. It is defined only on its inner bor- 
der, and for a short distance on its upper surface. 
The upper external connecting convolution in the idiot woman (Plate XXI. fig. 10, a) 
does not completely bridge over the external perpendicular fissure on either side, but 
is more nearly superficial throughout on the right hemisphere ; in the idiot boy (Plate 
XXII. fig. 14, a) this convolution dips downwards into the internal perpendicular fissure, 
becoming partly concealed on both sides. In the perfect brain (Plate XX. fig. 7) it is 
quite superficial throughout. In the female idiot, on the left side, the second connecting 
convolution (Plate XXI. fig. 10, (3-[ 3) is massive and double, one part ending in the bent 
convolution, and the other in the upper temporal ; the third (y) ends in the middle tem- 
poral, and the lowest one (&) both in that and the lower temporal ; on the right side 
the second, also double and very tortuous, runs by its upper part into the parietal lobule 
and the supramarginal lobule, and by its lower part into the upper temporal, whilst the 
third and fourth are blended, and end in the middle and lower temporal. In the idiot 
boy (Plate XXII. fig. 14), on the left side, the second connecting convolution (/3-j3), very 
broad and tortuous, runs into the bent convolution, the upper temporal, and the middle 
temporal ; the third (y) and fourth (b) connecting convolutions join the middle and lower 
temporal ; on the right side they are more tortuous, and serve to connect the same parts, 
the second one also joining the parietal lobule. In both idiots the second ((3), third, 
