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the following with regard to the tonic reflexes of the labyrinths on 
the eye-muscles: 
1. With the rabbit every position of the head corresponds with 
a special state of contraction of the eye-muscles and therefore with 
a special position of the eyes, which lasts throughout the time that 
the head retains the same position. 
2. With the rabbit for the rectus externus and internus no reliable 
data could be found in the bringing about of these tonic reflexes 
of the labyrinth. It is especially the rectus superior and inferior 
which cause the vertical deviations of the eye and the two obliqui 
which cause the rotation movements. 
When this happens, the two recti, just like the two obliqui, act 
as antagonists, on the other hand, changes of the lengths of the 
recti may combine with those of the obliqui in various degrees. 
So these two groups of muscles act independently of each other 
(though of course dependent together on the labyrinths). 
3. When the head stands with its muzzle vertically upwards, 
the two obliqui superiores (right and left) are in a state of greatest 
contraction, the two obliqui inferiores in a state of greatest 
relaxation. 
The upper cornea-poles of both eyes are then rolled forward. 
When the head stands with its muzzle in a position vertically 
downwards, the two obliqui superiores are in a position of greatest 
relaxation, the two oblig. inferiores in a position of greatest con- 
traction. The upper cornea-poles of both eyes are rolled backward. 
For all other positions of the head we find contractions, lying 
between these two extremes, the two eyes always react with rollings 
in the same direction. 
4. When the head is in side-position (left) the right rect. inf. 
and the left rect. superior are in a state of greatest contraction, the 
right rectus superior and the left rectus inferior in a state of greatest 
relaxation. Then the right eye has its maximum deviation downward, 
the left eye its maximum deviation upward. When the head is in 
side position (right), the left rect. inf. and the right rect. sup. are 
in a state of greatest contraction, the left rectus superior and the 
right rect. inf. in a state of greatest relaxation. For all the other 
positions of the head we find states of contraction of the rectus 
superior and inferior lying between these two extremes. Both eyes 
always react with opposed vertical deviations of the eye. The rectus 
superior of one side and the rectus inferior of the other side react 
in the same sense. 
5. When we start from the normal head-position and we turn 
