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quite distinct while the animal was investigated with open eyes. Lying 
on its sides, on its back and when theanimal wassuspended with the head 
upwards, the head was brought into its normal position. When 
hanging with the head downwards, the cervical vertebral column 
was flexed considerably. It is evident, therefore, that a/so after removal 
of the greater portion of the cerebellum optic “Stellreflexe” still react. 
In cats the same optic ‘“Stellreflexe” may be observed as in dogs. 
Young, tame cats are fittest for this purpose, as most full-grown 
cats are too wild when being examined in the air, and thereby 
‘hamper the experiment. 
SUMMARY. 
Cats and dogs deprived of their cerebrum possess the same four 
groups of ‘“Stellreflexe”, that have been described in a previous 
paper for rabbits. 
In the air these animals depend on the “Labyrinth-Stellreflexe” 
towards the head and on the cervical ‘‘Stellreflexe” connected with 
them. When in such animals both labyrinths have been extirpated, 
they have completely lost their sense of orientation. 
It is quite different with dogs and cats with cerebrum. When 
they are trying to find their orientation in space, they make use 
also of their eyes. 
This may be demonstrated by examining them freely in the air 
after bilateral extirpation of the labyrinth. 
Directly when the extirpation of the labyrinth has been carried 
out, dogs lose their sense of orientation almost completely, cats in 
a large degree. After a few days the animals have learned to use 
their eyes and sooner or later they are able, without labyrinths, to 
bring their heads into the normal position from the most varying 
positions in space. When watching the animals, it will be seen a 
