‘“‘DIE LOKALISATION IM GROSSHIRN”’ 499 
and whose responses to excitation occur in a definite regular 
manner time after time. The group of cells in the medulla 
oblongata which responds to increase in the concentration of 
the hydrogen ions in the blood by a respiratory impulse may be 
taken as a case in point. Probably there is such a definite 
group of cells from which arise impulses leading to movements 
of the respiratory muscles, and it is probable also that such 
impulses do not arise from any other group of cells. The evi- 
dence in favor of the normal participation in respiratory move- 
ments of accessory respiratory centers in the spinal cord does 
not appear to me to be conclusive. To this extent and in this 
sense, the respiratory center is a definite circumscribed center. 
But the question does not end here. ‘The experimental evidence 
now at hand on respiratory movements alone is incompatible 
with the idea of such a circumscribed center as the complete 
controlling mechanism. Anatomically, the central respiratory 
mechanism is not very thoroughly known. Experimentally, it 
is a system of great neurological interest. This interest is 
heightened for the student of the speech mechanism by the 
fact that every afferent impulse involved in the control of respi- 
ration is involved also in the control of speech. And when we 
consider that speech involves respiratory movements, most 
certainly under cortical control, the idea of a circumscribed 
respiratory center becomes hopelessly inadequate to account for 
all respiratory movements that are possible in man. A complex 
mechanism consisting of groups of nerve cells more numerous 
and more widely separated in man than in the turtle becomes a 
necessary postulate. 
The argument on shock may be summarized by saying that 
von Monakow in his theory of diaschisis has granted all that 
could reasonably be asked for shock, i.e., it is a temporary effect 
from which the cells recover fully, but never assume any greater 
function than their normal function in an intact nervous system. 
One may be pardoned, perhaps, for suggesting that, before 
any hypothesis of shock as a consideration influencing our inter- 
pretation of the function of any level of the central nervous 
system is accepted, we find out just how necessary any such 
