714 
Theorie, wie er ja selbst zugesteht, total unmöglich, weil eben das 
operierte Labyrinth fehlt und also nicht überwiegen kann über das 
gesunde, welches durch die kalte Ausspülung gelahmt werden soll; 
es sollte also nach Barrens in so einem Fall gar kein Nystagmus 
auftreten, was aber den klinischen Tatsachen vollständig wider- 
spricht” (S. 1817 und 1318). This argument, however, is not valid. 
Brcnterew’s'!) wellknown experiments have shown us that when 
we extirpate a labyrinth and remove the other after some days, a 
nystagmus will occur again in the direction’) of the labyrinth that 
was removed first. So, if the cold-water-nystagmus were resulting 
from extirpation of the labyrinth on the douched side, we might 
also expect, some days after unilateral extirpation, on douching 
the unimpaired ear, a nystagmus towards the extirpated side. Indeed, 
Barters*) himself has suggested this interpretation. Another argument 
put forward by Barrers®) against Barany’s theory, we do not quite 
understand. In a rabbit, with one octavus cut through, a cold-water 
or a warm water flow into the meatus of the unimpaired ear could 
provoke a nystagmus only towards the unimpaired ear. This finding 
of Barrers’s is not explained by Barany’s theory nor even by that 
of Barrers. Neither were we ever confronted with this case in a 
prolonged series of experiments’). It is difficult to say what may 
have led to Barrers’s abnormal experience. It would be better 
perhaps in similar experiments to perform an extirpation of the 
labyrinth than a section of the octavus, since the latter operation 
may be attended with lesions of the central nerve-system. 
Another cogent argument against the theory of Barrers, put forward 
also by Barrers himself, is that experimenters succeeded, by provo- 
king a caloric nystagmus with various positions of the head in space, 
in obtaining now a nystagmus towards the non-douched ear, now 
again towards the douched one. This, indeed, is the main argument 
that turns up repeatedly in the literature. Still, it cannot be adduced 
against Barrers’s theory without also considering that, when examining 
1) W. BecutEREW. Ergebnisse der Durchschneidung des N. acusticus nebst Erör- 
terung der Bedeutung der semizirkulären Kanäle für das Körpergleichgewicht. 
Pflüg. Arch. Bd. 30. (1883) S. 312. 
2) In speaking about a nystagmus in a certain direction we always mean a 
nyst. with the quick component in that direction. 
3) M. Barrens. Ueber die vom Ohrapparat ausgelösten Augenbewegungen 
(Ophtalmostatik). Klin. Monatsbl. f. Augenh. Jhrg. 50. (1912) S. 200. 
4) Discussion Verh. d. Otol. Gesellsch. Frankfurt. (1911) S. 214. 
5) See F. Qurx. Ein Fall von translabyrintharisch operiertem Tumor acusticus. 
Verh. d. Otol. Gesellsch. Hannover (1912) S. 252 
