1101 



agaiiLsl the wall, it cannot deviate in that direction and in this 

 manner the straight line of gait along the wall becomes easier. 



(/. When we examine the gait of these cats carefnlly, we di recti j' 

 see that the fore leg is stretched and lifted high. On the 

 following picture (fig. 2), a high magnification after a film lepro- 

 dnction, this is clearly seen. Without much difficulty one recognises 

 the parade-step, as i.a. is published by Luciani and v. Rijnbekk in 

 their investigation on the ceiebellum. From my own experiments^) 

 on dogs, of which a leproduction (fig. 3) is placed next the cat's, 

 and which is made of a |)hotograph, one sees the confirmation plainly. 



Fig. 2. 

 Gat. extra-cerebellar, 



Fig. 3. 

 Dog. intra-cerebellar, 



Of importance is the fact that in the dog the parade step occurred 

 after operating in the cerebellum' {^i^. 3), that in the cat, after 

 operating ^.c^ra-cerebellar (fig. 2). 



Other symptoms important for this report are not found in the 

 operated cats. Yet the results lohich loe obtained, support the suppo- 

 sition that the sensonj cerebellar ataxia occurs, mhen the afferent 

 tracts, inhich from the medulla and the vestihuhir onjan pass on 

 towards th . cerebellum, during their course to that organ, are inter- 

 rupted in some loay or other. 



In connection with the above-said a few points still rest to be 

 spoken of: 



1. how can it be explained that in my extra-cerebellar operation, 

 the parade step was perceived, while on the other hand the cock- 

 step and the "no"-nodding etc. as described by e.g. Luciani, v. Runberk 

 and myself were missing. 



I think 1 must look for the reason tiiat in all these cases the 

 same operation always was done, i.e. transsection of the posterior 

 funiculi medullae, of the ventral and dorsal spino-cerebellar tracts 

 of the funiculus lateralis medullae and of the vestibular organ at 



1) Gerebellair ataxia Psych. Neurol, hi. 1909. 



