STRUCTURAL ALTERATIONS IN NERVE CELLS 207 
especially that of changes in the spinal cord, leads me to believe that some difference, notably in 
the manner of distribution and form of the Nissl chromatic bodies, can be made out in the cranial 
nuclei. 
Individual variation no doubt plays a part in the production of these cell changes, but that 
there may be much difficulty in recognizing them is, I think, shown by tlie divergent results 
obtained by Schawbe and Bernheimer in the case of the Ilird nerve [loc. cit.) 
Division of the Facial Nerve at the Stylomastoid Foramen 
Experiment I. Facial trunk exposed at its exit from the stylomastoid foramen, and torn out; 
complete paralysis of the ear, face, and lid muscles resulted. Animal killed on the 2C:h day. An 
examination of the nucleus of origin showed that in about J of the cells no change could be 
detected. 
Among the remaining cells several varieties of alteration noted. 
(i) The most common is that in which the chromopithic masses, losing their stichochrome 
arrangement, become dispersed as minute blue particles over the body of cell, the nucleus being 
situated centrally, and normal in appearance. 
(ii) A condition almost exactly similar to that described as found in the spinal cord 
(Experiment 2) with similar alteration in the contour of the nucleus, and the appearance outside it 
of a reddish zone indicating commencing chromatolysis. 
(iii) Very rarely cells were found exhibiting the eccentric nucleus and disintegration of the 
protoplasm from the periphery. 
Experiment 2. Operation similarly performed, but animal killed on the 14th day. The 
appearances are almost exactly similar to those detailed above, and there is the same proportion of 
normal cells. 
Experiment 3. In this case the facial nerve was divided, so that the auricular branch was 
left intact, the same class of changes found, but almost half of total number of cells appeared 
normal. An examination of the nucleus of origin on the intact side showed the presence of a 
few cells whose structure was similar to that of certain of the altered cells in the opposite nucleus. 
Division of the IIIrd Nerve intracranially 
Professor Sherrington kindly gave me the corpora quadrigemina of a Cat and a Monkey 
in which this operation had been done and a third specimen of the oculomotorius nucleus in a cat 
was prepared by myself. 
The corpora quadrigemina of a Man in whom the eyeball liad been enucleated six months 
previously, were also examined. 
Experiment i. Cat. Killed on the 8th day. The changes are very slight and are just 
sufficient to enable one to distinguish the side of lesion by examining with a high objective. The 
characteristic change is again that the blue chromopithic masses lose their striated arrangement and 
become disseminated throughout the protoplasm as minute bluish particles. In some the nucleus 
is diminished in size and has a wavy outline, and a few show the type with the eccentric nucleus 
or with a clear, reddish zone round the nucleus. Among the normal cells of the oculomotorius 
