( 303 ) 



Photograph III has been taken of a section on the left border of 

 the defect, i.e. on the spot where the lesion begins on the left. 



Photograph IV has been taken of a section from tlie right median 

 part, directly adjacent to the median line. 



Photograph V represents a section from the middle of Ihe median 

 portion. 



Photograph VI represents a section very close to the prolongation 

 of the sulcus paramedianus dexter, but still within the median portion. 



Photograph VIII represents a section from the left lateral, being 

 the un-injured portion. It corresponds with the place in the right 

 lateral part, represented by photograph VII. 



If, by the aid of photograph III, we try to delimitate the exact 

 situation, especially of the different convolutions around the sulcus 

 primarius, it does not present any great difficulty to know which 

 is the lobus anterior and which the lobus posterior. 



The furrow, lying opposite the sinus Rhomboidales (R.), is the 

 sulcus primarius (s. p.). Ali that is lying before this sulcus, to the 

 left of it in fig. Ill, belongs to the lobus anterior, all that is 

 lying behind it, to the right in the figure, belongs to the lobus 

 posterior. 



The strongly developed anterior lobe is divided into four lower 

 lobules, which I have indicated sub 1, 2, 3 and 4, conform to 

 Bolk's description. 



Accordingly these numbers correspond with the lobes, designated 

 in the human cerebellum as Lingula, Lobus centralis and Culmen. 



For the posterior lobe I likewise followed Bolk's division, and 

 accordingly designated the folia by a, b, c and d; a corresponding 

 Avith Nodulus, b with Uvula, c with Pyramis and d with Tuber 

 vermis. Folium cacuminis and Declive. This latter would be the 

 Lobus simplex. 



The rationality of Bolk's division is demonstrated clearly by this 

 preparation, as the medullary rays of the folia are all of them 

 separately implanted in the medullary nucleus. 



The sinus Rhomboidales, the roof of the fourth ventricle, is desig- 

 nated sub R. Opposite to it, accordingly in the figure straight above 

 it, and separated from it only by the medullary nucleus, we find 

 the sulcus primarius (s. p.). 



As we stated before, it could not be decided with any certainty 

 from the macroscopial description whether the sulcus primarius was to 

 be sought for sub 2a or sub 2b (fig. II), and consequently the 

 situation of tlie defect could not be precisely defined ; it is therefore 

 necessary to determine with the utmost exactness in their mutual 



