CHANGES IN HUMAN CEREBELLUM WITH AGE 7 



to explain them in terms of body length and weight. At times 

 the encephalon is above weight and the cerebellum below weight, 

 or vice versa; in other cases the encephalon is above or below 

 weight, but the parts are proportionately developed. Chart 2 

 shows the range of some of these variations, accompanied by the 

 absolute weights of the parts of the brain. 



TABLE 3 



This table shows the absolute weights of the encephalon and the cerebellum and the 

 percentage weight- of the cerebellum tcith advancing years. Based on Boyd's 

 results as compiled by Sharpey 



Pfister states that the relative weight of the cerebellum varies 

 as much as 2 per cent, by which he means presumably that at 

 birth the relative weight would range between 4.7 and 6.7 per 

 cent of the weight of the encephalon, with a similar range of vari- 

 ation for successive periods. ]\Iy own results based on several 

 groups of cases show that 50 per cent of adult cerebella have 



