1361 
meatus at the prepared side a nystagmus is elicited in which slow 
contractions of the muscle are followed by quick relaxations and 
conversely, when syringing the other meatus a nystagmus occurs 
in which slow relaxations are followed by quick contractions. 
This finding calls in question the soundness of. Barters’ theory. 
If stimulation of the proprioceptive nerve-fibers in the eyemuscles 
were to generate the reflex for the quick phase, these nerve-fibers 
would have to be stimulated by contraction as wellas by relaxation 
of the muscle. Another theoretical, hitherto unrecorded objection is 
this that with the compensatory eye-positions, in which also occur 
considerable contractions and relaxations of the eyemuscles, only a 
large deviation but not a nystagmus is observed. 
Ovr doubt proved to be well-grounded, as borne out by the 
following experiments in which novocain was injected into the 
isolated M. externus. 
Technical difficulties caused a failure of some experiments. Six 
experiments succeeded to perfection and all yielded precisely the 
same results. 
In every one of them the left M. rectus externus was isolated 
and the right N. trigeminus and all the eyemuscle-nerves were 
severed with the exception of the left N. abducens. 
Registration of the nystagmus evoked by syringing the left meatus 
with cold water (slow contractions of the M. externus, followed by 
quick relaxations). Hereafter injection of 0.75—1°/, of novocain into 
the isolated M. externus (Lower concentrations of novocain did not 
seem to distinctly influence the nystagmus). With the above-named 
concentrations not only the proprioceptive nerves were paralysed 
but also a paralysis of the motor eye-nerve manifested itself. 
Also during the complete paralysis the syringing was continued; 
after some time the eye-nerve recovered itself slowly. In this manner, 
while syringing continually, we were also able to observe how this 
recovery occurred. 
Now if the theory of Barrers is correct we have after the novocain- 
injection to expect at the moment when the proprioceptive nerve- - 
fibers are paralysed but the motor nerve-fibers are still functionating, 
a stage in which the quick phase of the nystagmus disappears, but 
the deviation still persists. Not before the moment when also the 
motor nerve-fibers are paralysed, will the deviation disappear also. 
Likewise during the recovery a stage of deviation is to be expected 
without a quick phase and only then, when the proprioceptive nerve- 
fibers begin to functionate, a normal nystagmus with a quick phase. 
A similar process has already long been known during narcosis. 
88* 
