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lie against the nucleus Deiters, still belong to the cerebellar nuclei. 
I presume that Saimazono arrived at this conclusion because from 
these cells also fibres proceed which join the brachium conjunctivium. 
But not merely large polygonal cells form a connecting bridge 
between the cells of the cerebellary nuclei and the oblongata. Many 
other smaller cells, some more nearly approaching the egg-shape, 
lie between the fibres of the crus cerebelli. 
In fig. 10 I give a sketch of a frontal section through the cere- 
bellum of a vulture, Catharistes astratus. I think that it will show 
the topographic conditions sufficiently clearly. 
I will only add that the lateral nuclei as well as the medial 
nucleus shows a relationship with the vestibular region of crus 
cerebelli and oblongata. 
Compared to the Reptiles, however, the birds have strongly. 
differentiated cerebellary nuclei. Although these do not rank exactly 
between the nuclei of Reptiles and mammals, yet they exhibit in 
many respects an intermediary course of development to that of 
the latter. 
Summary. 
If now we compare the nuclei cerebelli of mammals with what 
is to be found in the lower animals discussed here, we shall see 
how these nuclei of the mammals, in proportion so much more 
highly differentiated and lying entirely in the cerebellum, have 
gradually developed out of the more elementary forms. It appears that 
the cerebellar nuclei originate in connection with vestibularis nuclei 
and probably have differentiated themselves therefrom. Later in 
phylogeny they shift in a dorsal direction, partly by enlargement, 
but partly also by shifting in toto, thus becoming incorporated in 
the cerebellum itself. 
In the lowest animals the cerebellar nuclei are still in closer 
connection with the vestibular tracts, than in the higher vertebrates, 
where they are connected in the first place with the Purkinje cells. 
The assumption is clear that the dorsal shifting of the cerebelli 
nuclei takes place under the influence of the axones of the Purkinje 
cells (neurobiotaxis). 
