150 ALES HRDLIC'KA 



In the examination of any large group of people it will be found that 

 each given index will show a rather extended range of variation. A 

 certain part of this range will embrace the normal average, together 

 with the normal oscillations of the index for the anthropologically 

 purest part of that particular group; but as few larger ethnic groups 

 to-day are free from admixture, it may safely be expected that a 

 certain proportion of the indices obtained on the group will express 

 aberrations. Such aberrations may be detected by a proper seriation 

 and mapping out of the indices. But we are assisted in expressing 

 them, as in expressing the differences in the indices of separate ethnic 

 and even biologic groups, by definite subdivisions or classifications 

 of the indices. That is why this subject has received so much atten- 

 tion. 



But such classifications, to be of real value, should self-evidently 

 be as little arbitrary as possible, and have the closest attainable relation 

 to natural groupings. 



These facts were well recognized from the start in anthropology, 

 and earnest efforts were made to arrive at the most logical classifica- 

 tions. For guidance there were on the one hand the principal natural 

 subdivisions or races of man, and on the other an augmenting and 

 comprehensive supply of measurements. It could readily be seen that 

 a classification of any index which would not harmonize with the 

 distribution of the index in at least the principal groups of mankind 

 would not be of any great utility. But it was also soon recognized 

 that even the principal races of man were not in all respects far 

 enough distant to give alone a sound basis for classification. It was 

 then that recourse was had to mathematical procedure. By taking all 

 the available indices on man regardless of racial subdivisions, ranges 

 of indices could be obtained which applied to the human family as a 

 whole; and these ranges gave certain averages as well as minima 

 and maxima which could serve as bases of mathematical classification. 

 From an insufficiency of data however and from other causes, there 

 arose numerous individual differences of views among working anthro- 

 pologists as to exactly where to establish the boundaries of the sub- 

 divisions of the various indices, and also as to the best terms for the 

 different subdivisions, which gave rise to a considerable confusion. 



To-day anthropology has ceased to regard the grouping and naming 

 of the indices in the somewhat fetishistic light in which it looked upon 

 them before. The arithmetic and graphic presentation of the dis- 

 tribution of each index has become the essential procedure in all 



