No. 633] SHORTER ARTICLES AND DISCUSSION 



359 



so that the facet range of each class is a fixed per cent, of the 

 mean facet value of its class. In other words the class facet 

 ranges vary in such a way as to give the same logarithmic range 

 to each class. 



As an illustration eye facet counts in 488 females of the unse- 

 lected white bar stock may be taken. The following table gives 

 the frequency distribution obtained when the classes have the 

 same facet ranges : 



130-135 0.2 



The same arrangement is shown in graphic form in the following 

 figure : 



There is a marked positive skewness. The next table uses the 

 same original data but with the facet range in any class equal 

 to ten per cent of the mean of that class : 



