45° POPULAR SCIENCE MONTHLY. 



tion. On the opposite side of the globe the western hemisphere points 

 south between the two seas. 



Having located the four races in their respective habitats, we should 

 next determine how each racial region was originally occupied, and 

 then note the ethnic effects produced by geographic peculiarities. 



The human species was differentiated from the other anthropoids 

 within Indo-Malaysia, where the climate was moist and warm and the 

 surface of the ground covered with a tropical forest growth. Such 

 were the surroundings that impressed themselves upon primeval man 

 and established the original type. These conditions were continued on 

 either side of the cradle-land toward the south along the equatorial 

 belt of the eastern hemisphere, which then stretched uninterruptedly 

 from the west coast of Africa, across the now partially submerged Indo- 

 African continent, into Melanesia and Australia. The shifting of the 

 thermal equator north and south of the geographical equator no doubt 

 caused the climate of this intertropical belt to vary slightly during 

 the ice-age ; but after the final retreat of the glaciers no further changes 

 occurred; so that, ever since, the environmental conditions of the east- 

 ern-equatorial region have remained to all intents and purposes the 

 same as they were in tertiary times. The Negro descendants of the 

 original inhabitants of these parts have thus been subjected since time 

 immemorial to somewhat the same external influences as impressed 

 themselves upon primeval man. It is natural, therefore, that the 

 blacks should conserve the conspicuous characteristics of the ape-like 

 ancestor and resemble the human prototype more closely than any other 

 people. Ethnically the Negroes are considered the lowest of the four 

 races of man; while geographically they may be characterized as the 

 children of the tropical forest. There are, to be sure, minor differ- 

 ences among them, arising from different lines of heredity, variations 

 of environment, migration and miscegenation; so that from the primi- 

 tive Pygmy people living in the recesses of the tropical forest, the line 

 of ethnic evolution may be traced through the pure Negroes, who 

 occupy the central equatorial belt, to the mixed Negroid types which 

 have come into contact with other races on the borders of the region. 

 But despite these differences the Blacks may still be regarded as eth- 

 nically similar and grouped together under one racial category; for, if 

 we confine ourselves to general characteristics, the typical Negro can 

 readily be distinguished from his human fellows by his black skin ; his 

 short curly hair, which is flat in cross section ; his long head with pro- 

 truding jaws, his flat foot, his broad nose and his round black eyes. 



The rest of the races of mankind were differentiated within the 

 northern hemisphere. Being affected from the first by the var3dng 

 environment of the glacial era, these northern emigrants were in- 

 fluenced bv different conditions from those to which their ancestors 



