A METHOD OF STUDY. 153 



(12) That a perverted form of prudential selection is threatening 

 the very existence of some nations that are counted highly civilized. 



(13) That the only remedy for these destructive tendencies lies in 

 enlightened and renovated institutional and prudential selection, and 

 the wide adoption of higher ideals. 



(14) That the most marked characteristic of modern human history 

 is found in the breaking down of many of the minor segregations, both 

 social and racial, of previous eras, and the ever-increasing intercourse 

 between nations and races. 



(15) That, notwithstanding the general trend of the new era, among 

 the millions of India many new castes have been established during 

 the past century. 



II. CONCLUSION. 

 1. What has been Gained by Recognizing Habitiidinal Segregation? 



Having completed our study of the four principles of segregation, let 

 us turn to the classification given in Appendices I and II, and consider 

 what lias been gained by the distinct recognition of habitudinal segregation. 

 In Appendix I the combined action of partition and election, produc- 

 ing segregate association of individuals according to their acquired 

 characters, and of isolation and selection, producing segregate inter- 

 generation of individuals according to their innate characters, is pre- 

 sented under the single term ' ' segregation. ' ' The action and reaction 

 between the two spheres of segregation is not clearly presented, and, 

 under the nomenclature there given, it would be difficult to consider 

 all the aspects in which this interaction is manifested. In Appendix 

 II, assimilational, stimulational, suetudinal, and emotional intension 

 are used to designate intensification, produced by the different forms 

 of accommodation and of acquired characters ; while other terms are 

 used to designate the intensification produced by the different forms 

 of unbalanced propagation, securing the survival of certain types of 

 variation in innate characters. The interaction, however, between 

 habitudes and aptitudes is not as clearly presented in these earlier 

 papers as in the chapters of this volume. 



2. A Method of Study tfiat should be fully Applied. 



I believe the facts of distribution to which I call attention are of 

 great importance, and that the methods of collecting and of exhibiting 

 by which these facts have been brought to light is worthy of being 

 applied in other fields. This method may be regarded as a develop- 

 ment of the study of "centers of creation," initiated by Louis Agassiz 

 and transformed by Darwin, Wallace, and others into the study of 

 geographical distribution as affected by migration and divergent eyo- 



