76 
DR, C. E. BEEVOR AND MR. V. HORSLEY ON THE EXCITABLE 
Hence we were not surprised to find that in the internal capsule there were fibres, 
excitation of which produced closure of the opposite eyelids only. 
(c.) Pursing of the Xtps.—This is another imperfectly bilateral movement, it being 
most marked always on the opposite side. 
(d.) Retraction of the Angle of the Mouth. —Rarely have we observed truly 
bilateral, i.e., symmetrical, retraction of the angle of the mouth, this being the 
exception to the rule of retraction to the opposite side. 
Class III. 
(a.) Pouting of the Lips. —This eversion of the lips appears to be truly a bilateral 
movement. 
(b.) Mastication. —So far as we have been able to observe, this complex movement 
is mainly bilateral, but we are compelled to postpone its detailed consideration until 
our analysis of its cortical representation is complete. 
(c.) Swallowing, including movements of the Soft Palate. —This in our experience 
of the capsule has always been bilateral on excitation. 
(d.) Adduction of the Voccd Cords has been shownto be perfectly bilaterally 
represented. 
(e.) Bilateral Movement of hath Elbows. —This (as flexion) we have found to occur 
four times altogether in our experiments, when the internal capsule of one side has 
been excited. The occasions, however, on which this was observed were so few, and 
the movement so slight and limited that we cannot regard it to be a proof of bilateral 
representation of this segment of the upper limb in one hemisphere. Moreover, 
during a long series of experiments upon the cortex this was never observed. 
The explanation of this phenomenon we prefer to postpone until further 
knowledge makes its discussion profitable. 
It occurred at point 57, and only in the central t Groups, Nos. IV., V., VI. 
To sum up, therefore, we consider the following movements to be alone truly 
bilaterally represented. 
Pouting of Lips. 
Mastication. 
Swallowing. 
Adduction of the Vocal Cords. 
It will now be expedient to describe the general results obtained by the various 
groups of experiinents. 
* Krause, in tlie Dog ; Semon and Horsley, in the Monkey. This is denied by Masini, and by 
Gaeel and Dob. 
t I.e., opposite the middle level of the capsule. 
