VIII 



THE HIND-BEAIN 



479 



posterior part of the vermis, the tendency was to fall backwards. 

 Thomas (1897), on the contrary, found a special relation in dogs 

 between the vermis and the muscles of the anterior portion of the 



L ans 



imp 



FIG. 240. Lobular division of dog's cerebellum. (Bolk.) 



trunk, and between the hemispheres of the cerebellum and the 

 muscles of its posterior portion. 



But it was van Eynberk who first provided an experimental 

 basis for the theory of cerebellar 



localisation, taking as his guide ^f^a^n^, 



Bolk's work on the comparative // ~*\.^ 



anatomy of the mammalian cere- 

 bellum. 



He attempted to test Bolk's 

 inductions experimentally by cir- 

 cumscribed extirpations of certain 

 lobules, and to this end performed 

 numerous experiments in the 

 Physiological Institute in Eome 

 (1904-8). As all his work was 

 carried out on the dog it is useful 

 in the two accompanying figures 

 to reproduce a diagram of the dog's 

 cerebellum divided into lobules 

 according to Bolk (Fig. 240), as 



tt -4.4. i 2 il- u Fl - 241. Sagittal section of dog's cere- 



well as a sagittal section, which beiium to show depth of rafik The 



abbreviations on both these figures refer 



to the diagram of Fig. 239. 



allows us to compare depths of 



the interlobar and interlobular 



sulci, and the varying size of the lamellae of which the lobules are 



composed (Fig. 241). 



The new facts established by van Eynberk may be grouped as 

 follows : 



(a) Alter the total or partial extirpation of the lobulus simplex 



