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n. lingualis (group 6), the cicatrice was opened again, and after it had 
been ascertained, that the nerve-ends had grown together and that 
the peripheral portion was myelinised already, the central eut-end 
of the nervus lingualis was prepared again, and cut out with a part 
of the surrounding connective tissue as far as it was possible to 
reacli it, the connective tissue being exstirpated because it might be 
possible that some nerve fibres from the central end of the lingualis 
had grown into the connective tissue and from there had reached 
the point of joining of the two nerve-ends. Ten days were allowed 
to the eventually cut nerve fibres to degenerate, and after that time 
the animals were killed and prepared after the manner described 
above. Ten days may be supposed to be entirely sufficient for the 
degeneration of all the nerve fibres eventually supplied by the central 
portion of the lingualis nerve. 
One of these experiments, which looked entirely suecessful, was 
studied as accurately as possible, and gave the following results: 
from the central portion of the lingualis nerve not a single nerve 
fibre entered the peripheral lingualis, nor had any other nerve (a 
small muscle nerve for example) regenerated into the peripheral 
lingualis, except the nervus hypoglossus. From the central cut-end 
of the hypoglossus, which was in full process of regeneration, a 
large number of regenerating nerve fibres had grown out and had 
all penetrated into the peripheral end of the nervus lingualis. Only 
a very few tibres had grown into the perineural connective tissue 
around the lingualis nerve. Inside the tougue all the lingualis 
branches were full of regenerating fibres, the hypoglossus branches 
were entirely devoid of them. 
The regenerating fibres, which here could have no other source 
than the hypoglossus, had followed the course of the lingualis nerve 
down to the smallest branches of the nerve plexus in the mucous 
membrane of the tongue. Of so-called autogenic regeneration (A. BETHE) 
no trace was found (only full-grown animals were used for experiments). 
The fibres of the hypoglossus nerve, having arrived at the end of the 
terminal branches of the lingualis, begin to form nerve-endings of 
different patterns. It is here’ not the right place to describe elaborately 
the differences in form and in extension of the nerve-endings. I hope 
to do that in extenso elsewhere. Here I will only mention two or 
three points. 
It is certainly an interesting fact that the hypoglossus fibres after 
having penetrated into and arrived at the end of the lingualis tract, 
begin to form terminal branchings and different end-bulbs. But net 
only that they form nerve-endings in the connective tissue, but 
