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DR. F. SEMON AND MR. V. HORSLEY ON AN INVESTIGATION 
that we have observed. {Vide also FRANgois Franck, Lepine, Bocheeontaine, 
Danilewskv, Goldstein, Sihler, Mxjnk, &c.,and our remarks on the internal capsule.) 
h. Intensification of Respiratory Movements .—If the electrodes be moved over 
the surface of the sigmoid gyms it will be noticed that as soon as they are placed 
opposite the lower or outer end of the crucial sulcus, there is then, together with the 
now very slight acceleration in rate, a distinctly more energetic action of the vocal 
cords. Both the abduction and the adduction movements are more pronounced, and 
as the electrodes are carried back to the lower end of the postcrucial gyrus, i.e., over 
tile area of reiiresentation of the fore-limb, this intensification becomes still more 
marked, and is occasionally accompanied by slowing, and may in short be said to be 
there localised, as from this point upwards it gradually diminishes over the surface of 
the gyrus. 
These observations are interesting in connexion with those made by Masini upon 
the distribution of the laryngeal represention in the Dog. {Vide History.) 
In reviewing the results just noted, we wish to point out that if the excitation 
of the cortex be first attempted with an extremely weak current and if then the 
stimulus be increased, the first effect in response to the weak current is the respmatory 
acceleration before noted, and the next effect is the intensification of the respiratory 
movements. The purposive adduction obtained in the phonatory centre as a rule 
requires the strongest stimulus. 
This has been found to be the case by most observers, the distance of the secondary 
coil from the zero point of the ordinary DU Bois inductorium being required to be 
pushed, as Krause himself first stated, to 7'5 or even 4 cm.* Although we have 
made a special investigation of this point with very weak as well as stronger currents, 
and although we have been very careful to preserve the vertical position of the 
larynx, and to record even the slightest action, we have never observed the unilateral 
movements described by Masini. 
Epilepsy .—As in the Monkey, we have not infrequently observed epilepsy to 
follow the excitation of the cortex, this being more readily produced in the carnivorous 
animals than in the higher. During the epileptic convulsions the vocal cords usually 
after preliminary adduction exhibit clonic adductory movements, in no wise differing 
from those previously described, save in their intermittent character. 
Cat. 
We have made a large number of experiments upon the cortex of the Cat because 
we found very early in our investigations, in 1886, that the movements of the larynx 
represented in the cortex of the Cat were not the same as those which we had 
obtained from the Monkey or even from the Dog. In other words : contrary to what 
we have just seen, the movement of abduction was well represented in the cortex of 
the Cat, although we had never been able to find any genuine trace of it in the cortex of 
* Fara(U.sm, moreover, not Helmholtz modification. 
