' 846 
those which are spared here, do not at all belong. to the occipital 
pole, but they must issue from far more proximal parts of the Gyrus 
occipito-temporalis. 
This conclusion is the more valuable, if we look at the influence 
which the focus has had on the geniculo-cortical radiation and on 
the lateral geniculate body. 
To make this clear | have drawn in fig. 4 a normal section of the surroundings 
of this body and in fig. 3 a cell-preparation!) of the same, to make comparison 
possible. 
In these figures one sees the lateral geniculate body, which shows on frontal 
sections the form of a shoe (s. fig. 3) and in which can be distinguished a dorso- 
medial part: the caput, and a latero-ventral one: the cauda. 
Within its own fibre-capsule covering the whole of it, (s. fig. 4) layers of 
fibres — laminae medullares 
are alternately followed by layers of cells. The 
cells in the ventral layers are large, those in the dorsal ones much smaller, 
although, especially in the capital part large cells penetrate in these dorsal layers. 
The size of the dorsal celis differs a great deal between themselves. Many of them 
are very small. . 
In the normal fibre preparation the cauda contrasts but little against the caput, 
because the radiation of the optic tract has already begun in this proximal section. 
On the dorso-lateral side the lateral geniculate body is covered by the triangular 
area of Wernicke through which the geniculo-cortical radiation penetrates. In the 
dorsal part of this area (s. fig. 4) the fibre-direction is totally different from the 
transverse sectioned fibres of its ventral part. 
A rather thick layer of very thin subependymal fibres surrounds the area of 
WEBNICKE against the ependym of the ventricle. As soon as the geniculo-cortical 
radiation has freed itself from this area, it opens its way in elegant curvings 
through the fronto-occipital bundle and the retro-lenticular division of the internal 
capsule to the stratum sagittale externum. So it seems at least, although nobody 
will dare to make a decided conclusion about the origin of these fibres, crossing 
here in all directions. : 
If we compare the above described area of the normal brain with an identical 
of our quadrantic hemianopsia, it then follows, (not to mention the degenerations 
in the fronto-occipital bundle, in the mere proximally situated parts of the corona 
radiata, etc.) that the dorsal layers of the geniculo-cortical radiation, and more in 
particular of the area of Wernicke, are totally degenerated. The ventral division 
of this fibre-area on the other hand, is not much injured, neither is the neigbbouring 
dorsal and ventral part of the proper medullary capsule of the lateral geniculate 
body (s. fig. 6). In the cauda of the body we find intact lammae medullares. 
In the caput (in its dorso medial part) the proper medullary capsule is dorsally 
and ventrally gone as well as the striae medullares. All the cells of this caputare . 
(s. fig. 5) vanished, the dorsal as well as the large ventral ones. The layers in 
which they were situated are to be seen as thick layers of glia. The whole body 
1) The cell-preparations of this body have been drawn with the camera of Zeiss ; 
they are enlarged 20, times and reduced to 7/;) of their size by the reproduction. 
Idem with the retro-lenticular area. . 
