MULTIPLE NEUROMATA OF THE CENTRAL NERVOUS SYSTEM. Ct 
to a greater or lesser extent towards the cord, and from the point where this may be 
arrested there is an attempt at regeneration. If the old sheaths are uninjured the new 
fibrils grow out into the old sheaths, each leash of new fibrils representing a destroyed 
nerve tube. If the degeneration is arrested just within the pia and if the old sheath is 
injured, the new fibres grow into the pial spaces, forming neuroma nodules. The 
posterior root shows a similar regeneration, but here the fibres are not myelinated. The 
Weigert stain shows only a few fibres, while Cajal’s silver method reveals numerous 
fine fibrils reaching up to the cord. Nagerorre finds it difficult to explain why the 
posterior fibres of regeneration are without myelin. He states that the new-formed 
fibres may start from three points: the cell-body, the intra-capsular, and the extra- 
capsular portions of the axon. The fibres are not terminal but are actual new processes 
of the cell or collaterals of the preserved portion of the axon. The term “collateral 
regeneration” in tabes is thus used. Many of the new fibres, even those within 
the capsule, may show cones and massues de croissance. Similar appearances are 
found under normal conditions in the posterior root ganglia: in tabes and other patho- 
logical conditions there is only an exaggeration of the normal. Nacxorre has also 
earried out a series of transplantations of the spinal ganglia to the peritoneal cavity and 
other parts of the body, and has found that the change of nutrition has caused the new 
protoplasmic processes to change in type, e.g. to take on the aspect of the sympathetic. 
Under these abnormal conditions, the peri-cellular and peri-glomerular arborisations were 
also reproduced. 
NaGEorTe states that the regeneration in tabes cannot re-establish function, as the 
terminal massues and cones are arrested at the area of inflammation where the first 
fibres were destroyed. 
FIcKLER (1900) examined two cases of compression of the cord at the lower dorsal 
region, in both of which there had been a great amelioration of the cord symptoms for 
some time before death. He found above the compressed part numbers of fine axis- 
cylinders, especially in the adventitia of the small vessels of the cord. These appeared 
first in the vessels at the periphery of the grey matter in the corner where the anterior 
and posterior horns meet. At a slightly lower level the fibres passed in the vessel walls 
to the commissural vessels and thence to the vessels in the anterior fissure. Just above 
the point of greatest compression the fibres filled the anterior fissure and overflowed 
into the adjoining pia. Opposite the compressed part there were no fibres at all within 
the cord—all had passed into the anterior fissure and pia. Below the area of compres- 
sion the fibres, collected into small groups, passed again from the vessels of the anterior 
fissure to the commissural vessels and were distributed in the grey matter. On their 
whole course they were surrounded by a sheath of Schwann. Fick er states that these 
are new-formed offshoots of the fibres of the crossed pyramidal tract above the lesion, 
which in this way have restored connection between the fibres above and the ganglion 
cells below the level of compression. In the second case there were present nerve fibres 
in the posterior septum, which were looked upon as new-formed sensory fibres. FICKLER 
