88 Records of the Indian Museum. [Vol. XXIII, 1Q22.] 



The value of the Absolute Variability is for the 



Lower age group =65-4923 + 27939 mm. 

 Higher age group = 71-0720 + 4-1726 mm. 

 Difference = 5*5797 + 5*02 mm. 



The variability of the younger group is thus considerably 

 less, but the difference is scarcely significant. Even though we 

 cannot definitely assert that the variability is being reduced with 

 time, the above noticed decrease is certainly interesting as giving 

 an indication that such a view is not altogether untenable. 



If we turn to the Relative Variability, i.e. the Coefficient of 

 Variation, we find 



Higher age group =4-2073 ±'2470 mm. 



Lower age group =3-9545 + '1687 



Difference =02528 + -2991 



The difference is less significant than the previous one. But 

 the reduction in even the relative variability is distinctly sugges- 

 tive. 



Another point must be carefully noted. The variability of the 

 Anglo- Indian sample is not significantly diminished by selection 

 of age groups. Thus the high value of the variability (both 

 absolute and relative) is not merely due to the mixing of the 

 different age groups but represents a real degree of dispersion. 



