QUANTITATIVE STUDY OF THE PURKINJE CELLS 



249 



The figures for cell losses do not of course fully indicate the 

 loss in functional efficiency of such cerebella. Many of the 

 cells that remain are in the process of disintegration and there- 

 fore many of those included in the cell count probably have 

 little or no capacity for functioning. 



NUMBER OF PURKINJE CELLS 



40 50 60 70 80 90 IOC 



Chart 1 Showing the decrease in the number of Purkinje cells with advancini; 

 age. Based on the totals of the four areas given in table 5. The dots show the 

 relation of the six observed values to the graph as drawn. 



THE VERMIS 



Sections of the vermis were prepared in all cases and a few 

 preliminary coutits were made to determine whether or not it 

 would be profitable to make counts on all cases. The results for 

 the tuber vermis in five cerebella — two normal, one senescent, 

 and two subnormal — are given in table 7, and for comparison, 

 the averages of area 4 of both hemispheres are given also. 



No significant differences in the relations found in the ' two 

 sections appear from this table. The sections of the vermis 

 from the other cases were examined under the microscope with- 

 out counting, and as it seemed clear that they would not differ 

 materially from what had been found in the hemispheres, no 

 further counts were made. 



