910 
with tbe variations found experimentally); this is not the case with 
the sacculus otolithes. 
In the position whereby the extensors have their maximal tension, 
the utriculus otolithes stand horizontally and are hanging on the 
epithelium in the position of the minimal tonus, the utriculus oto- 
lithes also stand horizontally, but press upon the sensory epithelium. 
It follows, therefore, that it is not by pressing that the utriculus 
otolithes exhibit the greatest stimulus, but when hanging. 
Just the reverse is the case with the tonus of the flexors; this 
tonus is strongest when the otolithes press and weakest when 
they hang. 
The influence of the labyrinth upon the tonus of the flexors is, 
however, much less than that upon the extensors, and can be demon- 
strated only by special means, so that there is no room for doubt 
that at all events the strongest stimuli proceed from the hanging 
otolithes. 
Experiments upon rabbits, where the labyrinth on one side had 
been removed, sbowed that one labyrinth is connected with the 
muscles of both extremities, so that each utriculus otolith exercises 
its influence upon the muscles of both extremities. 
b. On the neck. 
For this the same holds as has been stated for the tonic labyrinth 
reflexes upon the muscles of the extremities, with but one single 
fundamental difference. Whereas, from experiments upon rabbits 
with one labyrinth removed, it appeared that each labyrinth is in 
conneetion with the muscles of both extremities, this is not the case 
with the neck muscles, where the influence is uni-lateral. From 
which it follows that one utrieulus otolith is connected with the 
cervical muscles of one side of the body only. 
Therefore, the fact that both utrieulus otolithes lie almost in one 
plane, does not imply that the removal of one labyrinth will not 
be followed bv any symptoms, as indeed is seen by the turning of 
the neck after a uni-lateral labyrinth extirpation. 
2. “Labyrinthstellreflexe’’. 
By this word those reflexes are meant by which the head is 
brought back from any abnormal position to the normal again. The 
centres for these reflexes, like those of the other “Stellreflexe”’, lie 
in the mesencephalon. 
