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 Habitudinal 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 has 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 that 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 evo- 
