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parts, that maj' be discriminated with sufficient distinctness (fig. II, 

 3 and 4). What we find indicated sub 3 is a coniform swelling, 

 consisting of a succession of folia, separated bj- sulci running in the 

 direction of the margo mesencephalicns. 



Accordingly^ it does not offer any difficulty to recognise in this 

 portion the lobus anterior. 



The case is different however for the folium behind this part 

 (fig. II sub 4) lying before the snlcus mentioned sub 2a. 



It would belong to the anterior lobe if this furrow were indeed 

 the sulcns primarius ; but as it is lying behind the sulcus sub 2h, 

 the direction of which is totally different from that of the other 

 sulci of the lobus anterior, the question arises whether this convolu- 

 tion sub 4 does indeed belong to the anterior lobe. 



The direction of this gyrus is totally different from that of all 

 the other convolutions lying before it, because it does encompass 

 the basis of the coniform swelling. Whilst the convolutions in the 

 anterior part are ranged regularly behind one another, the convolu- 

 tion sub 4 does diverge from that arrangement, becanse the former 

 convolutions are implanted in tliis latter. Relying only on the diffe- 

 rence in direction between these convolutions, one would be inclined 

 to consider as the sulcus primarius rather the sulcus sub 2h than 

 that sub %i. 



We see however, that the convolution sub 4, like that of the 

 coniform swelling, is running from the right to the left. It is unin- 

 terrupted and the initial direction of this curved convolution is 

 likewise towards the margo mesencephalicns. This — in addition 

 to the fact, that Bolk in his description of the cerebella of different 

 mammalia, likewise reckons the lower and more deviating con- 

 volutions to the lobus anterior — supports the opinion that the sulcus 

 sub 11) is not the sulcus primarius, as we might suppose, if relying 

 only on the difference in direction between the convolutions sub 3 

 and 4. 



The macroscopical description will therefore have to leave unde- 

 cided the question, Avhether the convolution sub 4 must be reckoned 

 to the lobus anterior or to the lobus posterior. 



Nevertheless it is of the greatest importance to delimitate exactly 

 to which portion of the cerebellum this convolution belongs, 

 because it has become evident from the figures I and II, that on 

 the surface it is precisely in this convolution that the greater part 

 of the defect is situated. The examination of sagittal sections of the 

 cerebellum will have to decide this question. 



All that is lying behind the anterior lobe belongs to the posterior 



