X CONTENTS 



PAGE 



/. Polydactylism 175 



g. Syndactylism 176 



h. Brachydactylism 177 



i. Other Deformities of the Hands 177 



41. Twins 180 



CHAPTER IV 

 THE GEOGRAPHIC DISTRIBUTION OF INHERITABLE TRAITS 



1. The Dispersion of Traits 181 



2. Consanguinity in Marriage 184 



3. Barriers to Marriage Selection 189 



A. physiographic barriers 189 



a. Barrier of Water 190 



b. Barrier of Topography . 196 



B. social barriers ... 198 



u. The Barrier of the Social Status 199 



d. The Barrier of Language 200 



e. The Barrier of Race 202 



/. The Barrier of Religious Sect 202 



CHAPTER V 

 MIGRATIONS AND THEIR EUGENIC SIGNIFICANCE 



1. Primitive Migrations . . 204 



2. Early Immigration to America 205 



3. Recent Immigration to America 212 



a. Irish . 213 



b. Germans . . . 214 



c. Scandinavians 214 



d. Austro-Hungarians 215 



e. Hebrews 215 



/. Italians 216 



g. Poles 218 



h. Portuguese 218 



4. Control op Immigration 220 



CHAPTER VI 

 THE INFLUENCE OF THE INDIVIDUAL ON THE RACE 



1. Elizabeth Tuttle . 225 



2. The First Families of Virginia 228 



