496 Dr Duckworth , Report on the brain of a 
9. Forceps major of the corpus callosum in the left hemi- 
sphere. 
With such extensive destruction of the right parieto-occipital 
area, with such marked modification of the temporal lobes and 
attenuation of the splenium, it is a subject of interest to enquire 
whether the commissural fibres connecting one hemisphere with 
the other (through the forceps major of the corpus callosum) 
are degenerate. Weigert preparations shew no such bands of 
degenerated fibres. 
The gyrus dentatus appears in these sections and contains 
cells with no signs of degeneracy. The prominence of the gyrus 
dentatus in this specimen is due to the small size of the splenium. 
10. The mid-brain and optic tract on the right side. 
The optic tract appears in the lower part of the section and 
again in the upper part of its course. In both regions patches 
of degenerated tissue occur. The absence of the external corpus 
geniculatum on this (the right) side has been mentioned already. 
Upon the free surface of the anterior corpus quadrigeminum, 
inflammatory change is evident : numerous cells have apparently 
invaded the brain-tissue and amyloid masses are numerous. On 
the other hand, the more centrally-situated parts, e.g. the red 
nucleus, present little or no change. 
11. The posterior corpora quadrigemina and the upper part 
of the pons. 
The sectional area is markedly smaller than the normal 
(cf. Fig. 11). The section is asymmetrical, for the right crus and 
the left posterior corpus quadrigeminum are distinctly smaller 
than the corresponding parts on the opposite sides. But Weigert 
preparations shew no actual patches of degeneration, the only 
difference observed being a paucity of fibre and cell-elements in 
the left posterior corpus quadrigeminum. The pyramidal tracts 
in particular, while differing greatly in actual sectional area, shew 
no degenerated parts. Upon the upper aspect of the corpora 
quadrigemina evidence of inflammatory processes (similar to those 
described in connexion with section 10) is observed. 
12. The bulb: in the region of the inferior olive (Fig. 12). 
No tracts of degenerated tissue occur. The right half of the 
section is smaller than the left. The chief points to notice are 
(a) the occurrence of inflammatory changes on the ventricular 
aspect of the section with commencing infiltration of the nervous 
tissue, and ( b ) the presence of numerous granules in the cell- 
substance of large cells identified as those of the nucleus of the 
twelfth cranial nerve. The granules in question are quite distinct 
from the Nissl bodies, for with acid fuchsin combined with methylene 
blue, both may be stained. The granules unlike the Nissl bodies 
acquire a bright pink tint with the mixed stain just mentioned, 
