454 POPULAR SCIENCE MONTHLY. 



southeast, but which has in the course of time become differentiated 

 from the Negroids and adapted to its peculiar surroundings. Toward 

 the northwest we find the florid-skinned, blond-haired Europeans, 

 whose ancestors are Mediterraneans and Asiatics, but whose distin- 

 guishing characteristics were undoubtedly acquired during the course 

 of their wanderings across the plain lands between the Pamir region 

 and the Baltic. In the southeast section finally, dwell the swarthy- 

 skinned, black-haired Indians, who came down from the northern plain 

 lands during prehistoric days and established their supremacy over the 

 scarcely differentiated black people of the peninsula. These distinc- 

 tions are not to be taken too definitely, however; for even as the three 

 sections of the Indo-Mediterranean-European section are intercon- 

 nected, so the corresponding ethnic types are blended along the lines 

 of transition, in such a way that it is as easy to pass from diversity 

 to unity as from unity to diversity in considering the characteristics 

 of the Caucasians. 



Before leaving the eastern hemisphere to consider the fourth racial 

 region on the other side of the globe, we should take a hasty survey 

 of the insular region of Oceania and determine the ethnic affinities of 

 the South Sea Islanders. These islands of the Pacific are so scattered, 

 and differ from one another so widely, that they cannot be said to 

 constitute a separate racial region. The most that can be done in the 

 way of classification, therefore, is to divide the archipelagoes into 

 groups, establish their relations with each other, and indicate their 

 connections with the mainland. 



Topographically the islands may be divided into two classes: con- 

 tinental and oceanic. The continental islands are adjacent to the 

 mainland and stretch out along the equator toward the east and south- 

 east. The oceanic islands, on the other hand, are grouped between the 

 tropics in isolated archipelagoes, extending more than halfway across 

 the Pacific. The lines of entry into this insular region lead back to 

 Indo-Malaysia, the cradle-land of mankind and the point of intersec- 

 tion of the three racial regions of the old world. Oceania was, ac- 

 cordingly, peopled from three sources, successive waves of Negro, Cau- 

 casic and Mongolic migration coming together in Indo-Malaysia and 

 spreading out again over the islands of the Pacific. 



The negro dispersion occurred first, probably in the early days when 

 the eastern-equatorial region still extended uninterruptedly far out 

 into the South Sea. As the configuration of the globe assumed its his- 

 toric form, many of the earlier land-bridges were broken, leaving the 

 blacks to become adapted to different insular environments. But as 

 the islands occupied were for the most part continental and situated 

 under the equator, the surrounding conditions differed but slightly 

 from those prevailing throughout the eastern-equatorial region. As a 



