493 
microceplialic idiot with bilateral porencephaly. 
be distinguished in the thickness of the ventricular wall, viz. an 
inner zone abutting on the ventricular cavity. This zone is poor 
in fibres and such as are stained are fine, wavy and short. Amyloid 
droplets and many deeply-stained nuclei of varying size are present. 
Next to this zone comes a second layer in which tangentially- 
directed bands of fine and slightly- varicose fibrils can be seen. 
As the section is followed peripherally (i.e. towards the exterior), 
the tangential arrangement of fibrils gives place to an irregular 
network in the meshes of which are crowds of amyloid masses. 
Still nearer the surface is a zone in which nerve-cells occur. 
These are not numerous nor can the usual types be distinguished. 
Nerve-fibrils are still seen, but are less plentiful and the amyloid 
droplets are also more scanty here. Many small deeply stained 
nuclei occur. No definite marginal zone of tangential nerve-fibrils 
can be seen, but amyloid masses are found on the surface. 
The acid fuchsin stain (with methylene blue) shews a few 
nerve-cells of which the nuclei alone are distinct. The capillary 
vessels are perhaps slightly distended, but no definite evidence 
of degenerative change was obtained. 
2. The precuneus and adjacent part of the depressed cortical 
area. 
In these sections, part of the superficial blood-clot is shewn. 
Where this rests on the depressed cortex, the margin of the latter 
is fringed with numbers of amyloid droplets. The effects of the 
pressure exercised by the clot upon one of the gyri bounded by 
the compensatory sulcus, are definitely shewn. The gyrus is 
narrowed, so as to project towards the mesial aspect as a narrow 
opercular lip, sickle-shaped in section. The upper surface of the 
gyrus has been exposed to pressure exercised by the clot, and in 
it the normal cortical structures are unrecognisable. The lower 
surface of the gyrus preserves traces of the distinction of cortex 
and white matter. The latter contains amyloid masses. The 
cortex itself is not extremely modified, though the pia mater 
covering it is thickened and contains many droplets. 
3. The gyrus identified as the anterior precentral. 
The cortex is covered by a thick layer of felted fibres. The 
pyramidal cells are somewhat shrunken ; more important is the 
fact that their nuclei do not take up staining reagents well, while 
the cell-substance contains many granules staining deeply with 
acid fuchsin. 
4. The hippocampus major, gyrus dentatus, and fimbria 
(Fig. 14). 
These sections present few or no important changes. The 
amyloid droplets occur in the fimbria. The substantia reticularis 
alba (Arnold) presents a felted appearance. The hippocampal 
structures are not shrunken, as may be seen by comparing a 
