MULTIPLE NEUROMATA OF THE CENTRAL NERVOUS SYSTEM. (ks 
WALLER, in 1851, communicated to the Academie de Science the first facts regard- 
ing the secondary degeneration of peripheral nerves after section, and the term 
“Wallerian degeneration” is a permanent record of this historical fact. He also 
enunciated the law of the dependence of the nerves for their nutrition on trophic 
centres. Wat.rrR believed that the new nerve fibres in regeneration are formed as 
outgrowths from the central end and that regeneration could occur only when the peri- 
pheral end was joined to the central end. PHrttirpraux and VuLPIAN, in 1863, showed 
that a distal end separated from the centre could regenerate, and also that a portion of 
a nerve transplanted under the skin of another region contained nerve fibres after six 
months. They believed that the axis-cylinder was not destroyed during degeneration 
and that regeneration consisted simply in a re-accumulation of the myelin. NEUMANN 
(1868) maintained that during degeneration the axis-cylinder and the myelin of the 
nerve fibre’ were only modified chemically and that they fused into a specific nucleated 
protoplasmic substance which retained in some form the actual nervous elements. 
RaNviER (1871) maintained, on the contrary, that the actual nervous elements 
disappeared in toto. He definitely placed the theory of budding from the central end 
on a firm basis by showing that the new fibrils are formed by a longitudinal division of 
the axis-cylinder of the preserved central end. These newly formed fibres reach the 
distal segment and pass into the old preserved sheaths of Schwann. For nearly twenty 
years this view was generally accepted, and Vuupran himself, admitting that possibly 
ranches of nerves in the vicinity took part in the regeneration in the distal end, with- 
drew from his former position. 
In 1891 Von Bunener’s fundamental memoir marked a new phase, for he demon- 
strated the practical significance of his findings. Clinical observation, which had 
stimulated interest in this line of research, seemed to indicate that the time required 
for such a process as budding was not in accordance with clinical experience. ‘This 
was specially the case in secondary suture, where the rapid return of sensation and the 
re-establishment of conductivity seemed to indicate the re-union of the nerve. Von 
Bownener, using aniline dyes, asserted that the nerve fibre did not degenerate but was 
simply transformed into a nucleated protoplasmic band (Aaialbandfasern), or into 
individualised fusiform cells which arose from the mitotic division of the nucleus of 
the sheath of Schwann. ‘These spindle-shaped cells unite end to end as in embryonal 
development and again take the form of protoplasmic bands. The proliferated and 
enlarged nuclei group themselves in the direction of the fibres, and the homogeneous 
protoplasm lying between them soon assumes a fibrillar striation—the commencing 
axis-cylinder formation. Von BUNnengr has therefore modified and completed NEuMann’s 
view, and his work in turn has been completed by Durante, who has shown that the 
so-called Wallerian degeneration is really the formation of these Aaalbandfasern of 
Von Binener. To this process Durante has given the name of “ cellular regression,” as 
it is due to the abnormal activity of the nucleus and the undifferentiated protoplasm of 
the interannular segment, which, when the differentiated substances have disappeared, 
