548 PROFESSOR MARSHALL ON THE BRAIN OF A BUSH WOMAN ; AND 
100 to 53 and 100 to 52 respectively. This apparent relative increase in the posterior 
portion of the brain should rather be interpreted as due to a comparatively undeveloped 
condition of the antero-median region. 
It has already been mentioned that the corpora striata are in both idiots’ brains very 
small, whilst the optic thalami are relatively large. The part of the corpus striatum 
seen in the left lateral ventricle is, in the idiot woman, -35 inch long and T5 inch 
wide ; in the idiot boy '25 inch long and '15 inch wide. The visible portion of the 
optic thalamus in the woman is *8 inch long by *3 inch wide, in the idiot boy - 65 inch 
long by -4 inch wide. It has been previously noted that the large size of the optic 
thalamus corresponds with the great development of the temporo-parietal region in both 
the idiots’ brains, and the diminutive corpus striatum with the wasted form of the frontal 
region ; but besides the mere relative size of the two ganglionic masses, another condi- 
tion doubtless concurs to produce this correspondence, viz. the relative number of the 
radiating fibres which spring from them to branch out into the corresponding parts of 
the hemisphere. The corpora quadrigemina are quite of proportional size to the rest of 
the brain in both idiots, the superior one being larger as usual. The corpora geniculata 
are likewise well developed in both. In the idiot woman the corpora albicantia are 
separate but not prominent ; in the idiot boy the corpora albicantia are broad and some- 
what fused together. The pineal gland is proportionally large in the idiot woman ; 
in the idiot boy it was not found, having probably been destroyed. The habenulas 
could not be traced in either brain. The pituitary body in the idiot woman is very 
large ; in the idiot boy it has not been preserved, but the infundibulum is present and 
large. The cerebral peduncles in the idiot woman appear long and narrow, and the 
interval between them is deep ; in the idiot boy, on the other hand, they are broad 
and flat, and the interval between them is shallow. This may be due to elongation of 
the woman’s brain occurring as the effect of long suspension in spirit after complete 
removal of the membranes. 
In the preserved brains the pons Varolii is broader from before backwards in the idiot 
woman than in the idiot boy, measuring in the former nearly *6 inch deep, but only -5 
inch thick, in the latter only -4 inch deep and '5 inch thick: this appears remarkable, 
as the cerebellum of the boy is larger than the cerebellum of the woman. 
The medulla oblongata is large in both idiots : in the woman its greatest width is 
•7 inch, in the boy '6 inch; its proportions to the entire width of the brain are as 1 to 
5T4 in the former and 1 to 5'3 in the latter, instead of 1 to 7, the normal ratio. The 
olivary bodies are large, but especially so in the idiot boy ; the grey matter in their inte- 
rior is folded, as usual. In other respects the medulla is normal. 
The cranial nerves, so far as can be judged from those which remain in the preparations, 
are of full size, and, indeed, large in proportion to the size of the cerebral mass. 
The Cerebellum (Plates XXI. &XXII. figs. 10-16, Ce ). — As already shown, this organ 
in both idiots, though more highly developed than the cerebrum, is still small, especially 
in the idiot woman. All its parts, however, are present, though more or less reduced in 
size and in complexity of structure. 
