716 DR ALEXANDER BRUCE AND DR JAMES W. DAWSON ON 
take on a vegetative activity. The protoplasmic or plasmodial bands have thus arisen 
from the mitotic division of the sheath of Schwann uucleus and the augmentation of 
the protoplasm, while if each nucleus surrounds itself with protoplasm and individualises, 
instead of a plasmodial nucleated band we get the formation of fusiform cells. 
During the ten years following Von Btnenur’s fundamental work, a very marked 
tendency set in towards this new teaching, and so much did the peripherist view seem 
destined to replace the outgrowth theory, that many writers did not hesitate to speak 
of the death of the old view and by implication the death of the neurone doctrine. 
The writers whose uames must be mentioned during this decade are, with one or two 
exceptions, peripherists. 
STROEBE (1893) strongly opposed Von Bunener’s views. By a new axis-cylinder 
staining method he showed that the peripheral end and the intervening scar-tissue 
were neurotised by young fibres which passed from the old axis-cylinders. His con- 
tribution to this subject, in addition to the introduction of the aniline blue and safranine 
staining method, was his insistence on the completely passive réle played by the 
peripheral end as a conducting path or scaffolding for the young fibres. 
Gagorri and Levi (1895) studied the regeneration of nerves in the newly-formed 
tails of salamander. The tails were cut off in sunny weather, and new tails grew in 
about fourteen days. These cold-blooded animals were chosen because it was found 
that in mammals the inflammatory reaction was so intense as to make it impossible to 
distinguish between the young neuroblasts and the cells which had arisen from the 
proliferation of Henle’s sheath, the epi- and peri-neurium, or immigrated leucocytes. 
GaLeorr1 and Luvi found among the newly-formed muscle fibres more or less long 
chains of slender elongated cells, the chains usually ending in a cluster of radiating 
similar cells. The cells of the end cluster in their turn proliferate, elongate, and 
gradually become arranged in a chain amongst new muscle fibres. In the cytoplasm 
of each cell, by means of the gold chloride method, a granular filament could be 
recognised, and as this increased in amount the nucleus was pushed more and more to 
one side. This differentiation could often be observed in different stages in the same 
chain of cells. At first every element retains its individuality, then the processes of 
each cell unite in an imbricating manner and fuse to form nucleated bands which show 
a bulging opposite the nucleus. The granular filaments of each original cell unite 
when the cell borders disappear. The outer layer becomes condensed and forms a 
definite membrane to the band—the later sheath of Schwann. Specific myelin sheath 
stains were not used, but its development could be followed by means of aniline dyes 
which showed the double contour and constrictions of the fibres. 
The authors were convinced that these fusiform elements, in which the granular 
filaments form, arise from the proliferation of the nucleus of the sheath of Schwann. 
In the salamander the connective tissue cells could be easily distinguished from these 
cells, and there were few connective tissue elements and immigrating leucocytes between 
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