VII 



EACE8 AX I) TKOIM.ES 



In the thousands of years that cUipsed before the his- 

 torical i)eriod began, tliat continning ten(h>ncy to vary 

 wliich liad already differentiated the animal kingdom 

 inio genera and species, was operating to differentiate 

 maiilv'iiKl into varieties or races. ^ Associated in groups, 

 liie early men of the Paleolithic and Xeolithic periods, 

 moving from one territory to another under the pressure 

 of environmental changes, met and conquered or else 

 intermarried with otlier ])rimitive racial groups. From 

 this process of association, intermixture, and adaptation 

 to the necessities of climate and geographic environment, 

 certain characteristics emerged as stable physical pecul- 

 iarities of large populations. /To-day we distinguish a 

 yellow-skinned straight -haireil race, a hhick-skinnod 

 woplly-haired race, and a fair-skinned curly-haired race J 

 /But before we can identify any i)opulation group i^ 

 a true race we must show that certain traits or stable 

 pliysical chai'acters wliich it possesses are distributed 

 separately, are associated into types, and finall\\we must 

 show the hereditary character of these types.- J For ex- 

 ample, in the first place, we must show that such a trait 

 as blondness is diffused among large numbei-s of a popu- 

 lation; ill the second i)la('e, that blondness is more often 

 associated with tall stature tliaii witli sliort stature, thus 



1 Giddiugs, Principhs. \>. 2.30. 



2 Ripley, W. Z.—Thc Races of Europe, pp. 104-105. 



•J0,3 



