viii CONTENTS 



ination of Plate HI P 



( >.iliu the Metropolis of the Achatinellidae 4 2 



Mapof the Hawaiian Islands. 

 Plate I Eighl Genera of Achatinellidae. 

 Plate H MapofOahu, Hawaiian Islands. 

 PI it. II. Twenty-five Species of Achatinella. 

 Plate I II. Yariati.m and [ntergrading of Bulimella. 



Explan ition <<i Plate B 43 



Chapter V. — The Four Segregative Principles. 



Racial and I laltit udinal - tion J-5 - 5° 



Interaction of Acquired and Inherited Characters i.S 



regation a Fundamental Law 17 



Segregate Association 



Interaction of Racial and Social Factors 49 



Determinate Evolution of Evolutionary Terminology 50 



Segregation the Combined Result from Four Principles 5 1—55 



Racial Segregation Controlled by Two Principles and Habitudinal 



Segregation by Two 51 



I mportance of Isolation 51 



Definitions of the Four Segregative Principles 53 



Objections to the Terms , 54 



Interaction of the Four Principles 5S-7N 



Repeated Action of One or Combined Action of Several Principles. . 55 



Importance of Each of the Principles 56 



Two Methods of Generalization 58 



Change of Tradition in Chimney Swift 59 



Variation and Accommodation Two Methods of Adjustment 59 



Conditions Suddenly or Gradually Encountered 60 



Accommodation in Man 61 



Endonomic Selection 63 



Coincident Selection 64 



Endonomic and Coincident Selection Contrasted 65 



Coincident Selection Illustrated 66 



Endonomic and Coincident Influences Defined 66 



A Colony of Cats with Aquatic Habits 67 



Structural Isolation and Structural Selection Illustrated 6S-70 



Young Snails with Reverse Coil from that of Parents 70 



Mutations and Varieties 71 



Theories Compared 72 



Degeneration with Cessation of Selection 73 



ration in Eye-sight and its Lessons 74 



on in Breeding Instincts 75-76 



Mutation as Recenl ly Expounded by He Vries 77 



Selection and Inheritance of Acquired Characters 78 



Chapter VI. Analysis of the Four Principles of Segregation. 



Chief Divisions of the lour Principles 79-81 



Six Conditions on which Racial Evolution Rests 79 



Six Conditions on which Habitudinal Evolution Rests 80 



