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the cutting of the hypoglossus nerve. It is ceitainly interesting, that 
even in such atypie surroundings the hypoglossus nerve fibres try 
to build up their proper typical endformations. 
In the third place the following point may be mentioned. In the 
course of the branches of the lingualis nerve are distributed groups 
of ganglion celis of sympathetic nature, probably belonging to the 
chorda-tympani part of the lingualis nerve. The fibres of the lingualis 
(chorda tympani?) form a beautifully impregnated network with 
meshes and interwoven fibrillae on the surface of these cells. After the 
cutting of the lingualis nerve this network of fibrillae disappears 
entirely, the cells themselves undergoing apparently no alteration. 
The fibers of the hypoglossus nerve appear to be unable to regenerate 
this network of neurofibrillae, at least in all my preparations, even 
there where the nerve plexus in the mucosa and the submucosa was 
very well regenerated, and all the branches of the lingualis nerve 
were full of regenerating fibres, no trace of the above mentioned 
network could be found. 
To conclude, it appears from these facts that fusion of heterogenic 
nerve-ends is not only possible, but may lead to distinct regenera- 
live processes which do not differ much from these following on 
the fusion of homogenic nerve-ends. A functional (physiological) 
regeneration however does not take place, because the regenerating 
fibres are not able to reach their proper destination, and no contact 
with the muscle fibres is acquired. . 
And yet a certain amount of functional regeneration may be 
obtained after all. Firstly some fibres of the hypoglossus nerve will 
erow out, not into the neural tubes of the lingualis, but in the 
connective tissue of the perineural sheath. These fibres after a time 
will reach their destination, the tongue, and these fibres will have 
no difficulty in coming into contact with the adjoining muscle fibres 
and will form new motor end-plates on them. Secondly here and there 
in the preparations a fibre was found, which in forming terminal 
branches in the connective tissue of the mucous membrane of the 
tongue, had come in contact with the end ofa muscle fibre, and was 
seen to run alongside it for a distance (towards the centre of the 
tongue) and then to form a small end plate on the surface of the 
muscle fibre. This last mode of functional regeneration [ met with 
however only in a few cases. 
Leiden, 18 February 1818. 
