834 



peripheric liiiubar nerve of tlif inoculated side, in the lateral columns 

 of the inednlla spinalis and everywhere scattered among normal 

 fihres in pai'ls (d tlio cerel>elluin hiainsteni and cerebrnm. 



2"'' Cli.itnties of nervece//.t. 



(I. Destrnclion more or less of the nucleus 



/). Dissolntion of iViWI n m ps 



c. Grrannlating of nervetibrils 



(/. Goi.ui alterations of the intracellnlarfibrils 



fi. Presence of A'f^yriltodies 



/'. Retispersion and stretching of the Golgi apparatus 



fj. Babes' Knölchen mainly in (he ganglion spinalis 



3'^' Changes o/' the bloodvessels. 



a. Vessels studded with cellular elements 



b. Small infiltrations round the vessels of haematogenous elements 



c. Growing heie and theie (d" the «ndothelcells 

 4^*^ Changes of the nearoglin. Very slight. 



Trying to answer onr fii'st and second question with these facts 

 it IS obvious, llial of all the changes those of the nervefilir'es, especially 

 of the myelinshealhs are the most cons|Mcuous. 



As to the degeneration of the |)eiipheric nei've it is certaiidy not 

 a Wai.i^hik degeneration for: 



1'''. the cylindie-axis ure much less destroyed than are their 

 myelinsheaths. 



2'"'. there is s^ai'cely any i-eaction from the side of the cells of 

 Schwann. 



As to the degeneration of ilie libres in the medulla spinalis there 

 is no question of a system degeneration. The destroyed myelinsheaths 

 and swollen cylindre-axes can not be pursued up to their nerve- 

 cells, viz. in the neighbourhood of the ditTerent cellgroups, in the 

 medulla scarcely any destiuction o\' fibres is to be found. So the 

 destroyed myelin can be explained only by a direct influem-e of 

 the virus. 



Admitting that the lyssavirus propagates along the lymph or blood- 

 vessels and the virus itself or its toxines entering the nerve on 

 ditfereni spots destroys the myelin, than the qnestu)n arises why 

 precisely the nerve of the inoculated muscles has degenerated in its 

 whole length without any interruption whilst other peripheric nerves 

 either have a degeneration of their roots and the most central part 

 of the postganglionic part or ha\ e no degeneration at all. 



Admitting therefoie that the virus from the inoculated spot reaches 

 the cential nervous .system, it does not in the least exclude thai 

 along the vessels as well the virus is Iransported. In the meiiulhi 



