OP THE OEHTRAL MOTOR INNERVATION OF THE LARYNX, 
201 
the Dog’. It will be necessary, perhaps, first to explain that the arrangement of the 
convolutions in the Cat as regards the frontal lobe is in its chief features the same as 
in the Dog, only in miniature. See Plate 32, figs. 2, 3, 4, 5. Tlie coronal fissure bounds 
the sigmoid gyrus below, and riuining forward is separated from the supraorbital sulcus 
by the pillar or isthmus of tlie prmcrucial gyrus joining the antei'ior composite gyrus 
as before described. In front of the supraorbital sulcus and between that sulcus and 
the rlnnal fissure is situated, as in the Dog, the orbital lobe. The rhinal fissure, of 
course, separates the orbital lobe from the olfactory tract. We mention all these 
points because their special bearing will be seen directly. 
Phonation. —The bilateral adduction of the vocal cords, as in phonation, we have 
observed in the Cat to be more frequently represented in the coronal gyrus at its 
anterior extremity, near the anterior composite gyrus, at a point which is in a line 
with the crucial sulcus and in the upper part of the gyrus, i.e., close to the coronal 
fissure, at d', figs. 2, 4, 5. We have further observed that representation of bilateral 
adduction is also to be found in the area corresponding to that discovered by Krause 
in the Dog, i.e., just above and in front of the anterior end, of the coronal fissure, at 
d, figs. 2, 4, 5. This representation of adduction, whether in one place or the other, 
is very soon exhausted, although it is, when present— i.e., in a full-grown old Cat— 
well marked. It requires a moderate stimulus for its production, i.e., 7000 to 8000 of 
the Kronecker coil. 
Respiration, Abduction, Acceleration. —We have found that in the Cat there exists 
a point (at h, figs. 2, 3, 4, 5) in the lower border of the hemisphere, just above the 
rhinal fissure — i.e., in flie anterior composite gyrus—and just below the depression 
representing the antero-supra-sylvian sulcus, excitation of which produces well- 
marked— i.e., as long as the excitation lasts—abduction of the vocal cords ; and that 
the same effect is produced, in a diminishing degree, round this point as a focus, and 
occasionally passes above the supra-sylvian sulcus on to the coronal and upper part of 
the anterior composite gyrus. This cortical representation of abduction in the Cat is 
ver}' interesting, as probably indicating special respiratory requirements''’' in that animal, 
this deduction being confirmed by the ex})eriments of Legai.loisI' and others. Although 
we have found occasionally that in the Cat the prrecrucial gyrus gave upon excitation, 
as in the Dog, acceleration of respiration, yet this was not so marked. 
IntensiJicatioji. —Similarly, intensification also was observed, but in no great degree. 
Concomitant Movements. —Concomitant movements were observed (movements of 
the tongue, licking, mastication, and swallowing) when the anterior composite gyrus 
was excited, i.e., when opening of the glottis (abduction) was produced. But we 
constantly observed the abduction to be completely maintained while thoracic respira- 
* In the discussion following a demonstration of some of our exj^eriments at the 10th International 
Medical Congress, 1890, Prof, du Bois-Reimond stated that he had observed phonation in the Cat and 
Cow to be of an inspiratory nature. Prof. Exxer stated the same wdth regard to the Pig. 
t ‘ Sur le Principe de la Vie.’ 
MDCCCXC.-B. 2 D 
