134 DR. 0. E. BBBVOR AND MR. V. HORSLEY ON THE EXCITATION OE THE 
Having now described the methods of investigation, we will now give in detail the 
results obtained by stimulating (A) the cortex, (B) the internal capsule. 
In the description of the representation of movements obtained in the cortex w^e 
have thought it best to arrange the facts in the order in which the cortical areas were 
stimulated. This arrangement was similar to what we employed in the Bonnet Monke}^ 
beginning with the foci for the smaller movements before proceeding to those for the 
larger, as we found by experience that the former were the first to lose their exci¬ 
tability. We shall therefore describe the different movements in the following order :— 
Movements of the Eyes and Eyelids. 
Movements of the Face and Mouth. 
Movements of the Upper Limb. 
Movements of the Lower Limb. 
Besults of Excitation. 
(A.) Cortex.—Left Hemisphere. 
Movements of Eyes and Eyelids. 
(1) Both Eyes move conjuyately to the opposite side. —The representation of this 
movement we found to extend in front of the praecentral sulcus, i.e., to a slight extent 
just in front of its vertical limb, but lying principally in advance of the sulcus w. 
The focus of the area is situated in the centre of the gyrus, at the points marked 2, 
2, 2, in fig. 3. The whole representation extends as indicated by the stippling in 
fig. 1, Plate 18. The movement was also elicited from the centre of the gyrus, as 
above stated, at squares 3, 4, 5, 6 (fig. 3), but it was very slight, and at the angle 
formed by the two limbs of the sulcus there was no excitable point. 
As compared to the same movement obtained from the Bonnet Monkey, Macacus 
sinicus (see ‘Phil. Trans.,’ B, 1888), this result from the Orang was characterised as 
being much slower in development and execution—in fact, resembling rather the 
movemenfi^^ obtained from the angular gyrus in the Bonnet [vide Professor Schafer, 
‘Boy. Soc. Proc.,’ and confirmed by ourselves). 
As indicated in the title of this section, no other movement was observed than that 
of both eyeballs to the opposite side, unaccompanied by the commonly-associated 
actions of opening the eyelids, dilatation of pupils, and turning of the head. 
(2) Combined Movement of Eyelids opening briskly, Eyeballs turning to the opposite 
side, and Head turning to the opposite side. —This association of movements wns 
obtained at squares 24, 25, 26, 27, 111, 112, 113, 114, 115, 116, 117, 118, 119, and 
appeared to be equably represented over the (dotted) area (see fig. 2, Plate 18), wdiich 
is seen to be situated in the ascending frontal convolution. The sequence was that 
* First discovered liy Professor Fbrriek, ‘ Functions of the Brain,’ 2nd ed., p. 243. 
