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PROFESSORS D. FERRIER AND G. F. YEO ON THE EFFECTS OF 
causes the movement of the head and eyes to the opposite side, were practically 
intact. 
But though as regards discoverable symptoms the case was negative, the micro¬ 
scopical investigation of the brain revealed facts of great importance both as regards 
the anatomical relations and probable physiological significance of the prefrontal 
cerebral regions. 
The sections demonstrate the occurrence of secondary degeneration or sclerosis of 
certain fibres of the internal capsule and crura cerebri. These occupy the lowermost 
and most internal aspect of the transverse sections of the internal capsule, and the 
most median bundles of the foot of the crus cerebri. The further destination of these 
bundles, whether they end in the corpora quadrigemina or in the pons, was not deter¬ 
mined. But the facts demonstrated show that the prefrontal regions are anatomically 
in connexion with the median bundles of the foot of the crus and corresponding fibres 
of the internal capsule. 
Experiment 23 (Plate 27, figs. 74-86). 
In this animal the frontal lobes were exposed on both sides, and the cortex cauterised 
extensively towards the base of the three frontal convolutions. When this was done 
first on the left side the eyes were seen to be deviated to the left. On the right side 
the destruction was somewhat less extensive. In less than an hour after the opera¬ 
tion the animal was able to sit up and move about spontaneously, keeping its head 
down and its eyes shut. No further observations were made at this time. Next 
day the animal was found resting on its perch in a drowsy condition with its eyes 
shut and taking no notice of anything. But when a piece of apple was held under its 
nose, it at once put up its hand to seize it—smell being evidently retained. Tactile 
sensibility was also acute everywhere, as it moved if touched on the head, or on its 
hands or feet. It turned its head upwards and to the right when the right ear was 
tickled; and it frequently shook its head from side to side as if to remove irritation. 
The eyes being forcibly opened were seen to have a normal position, and the pupils 
of moderate size. 
Attention was suddenly excited by the attendant offering it the yolk of an egg. 
This it devoured with evident gusto. 
On the third day the same dreamy or drowsy condition was maintained, except 
when food was offered it, when it always exhibited interest. All its motor powers 
were perfect, and it turned its head alternately to the right and left, following an 
apple which was moved in front of it. Sight, hearing, smell, and taste were retained. 
On the seventh day the animal was still very dull, taking no interest in anything 
but its food, which it evidently enjoyed heartily. The movement of the head and 
eyes to either side was plainly observed without the slightest turning of the trunk. 
All its motor powers otherwise, and sensory faculties, were unimpaired. 
