OF THE CENTRAL MOTOR INNERVATION OF THE LARYNX. 
200 
which ai’e commonly spoken of as belonging to organic life, it is easy to understand 
that our results bring us to the conclusion that the phonatory movements of the 
laryngeal muscles, i.e., adduction, &c., are represented principally in the cortex, 
whereas the respiratory movements, i.e., abduction, chiefly in inspiration, adduction 
less commonly and imperfectly in expiration, usually find their origin in impulses 
emanating from the bulb. 
We have seen that the first of these functions, phonatory adduction, is represented 
most completely in the cortex the higher we ascend in the animal scale, and the more 
completely as the cortex is developed in the life of the individual, i.e., by age, while 
jmri passu, the function of respiration, although present in a minor degree, as 
evidenced by acceleration, is least represented where phonation is most completely 
developed. In further detail, adductory phonation is centred in the Monkey at the 
junction of the foot of the ascending frontal gyrus, and the base of the third frontal 
gyrus, in the Carnivora at the junction of the praecrucial, or prsefrontal gyrus, with 
the anterior composite and coronal gyri. Respiration is represented in the higher 
animals only as acceleration, and that above and rather in front of the focus of 
phonation. 
In the Cat only have we found a deliberate representation of abduction in the 
cortex. 
Turning now to the lowest part of the central apparatus, the bulb, we see that 
there is therein situated a small but concentrated focus on each side of the middle 
line for bilateral closure of the glottis, and outside that a small area, excitation of 
which produces unilateral adduction of the vocal cord on the same side. Above this 
region of adduction there is also a representation of abduction, i.e., inspiration. 
Finally we have found that, connecting the cortical apparatus with the bulbar 
apparatus, there exist numerous connecting fibres which can be analysed as they pass 
dovm from the cortex through the corona radiata and internal capsule towards the 
bulb; that as far as they are concerned they simply subserve the functions which are 
proved to exist in the cortex ; that the anatomico-functional arrangement of these 
fibres in the capsule enumerated from before backwards is :—acceleration of respiration, 
abduction, intensification, adduction ; and that their respective positions in the capsule 
are constant and strictly homologous in the different species of animals, according to 
the development of the cerebral hemispheres in the particular cases observed. 
These results are in complete concord with the ideas concerning the whole central 
nervous mechanism which innervates the larynx, ideas which were put forward by 
one of us (F.S.) at the International Congress at Copenhagen in 1884. We are 
enabled to state this the more positively for the reason that we have in our hands 
the notes of a large number of ablation experiments which, by their control of exci¬ 
tation effects, prove to demonstration the correctness of the views and opinions we 
have enunciated. 
2 E 
MDCCCXO.—B. 
