CONTENTS 



PAGE 



(1) Apparent revival of bygone institutions . . 227 



(2) Apparent disappearance of institutions . . 229 



(3) Instances of convergence .... 230 

 Chapter II. Can rudimentary institutions or organs reassume 



their primitive functions ? 232 



Section L Rudimentary organs . . . 232 



1. Animals. (1) Muscles of the ear in man. (2) The 

 abdomen and appendages in deep-sea hermit crabs 232 



2. Plants. (1) Hermaphrodite flowers in Melandryum. 

 (2) Branches of Colletia cruciata, Crataegus, Vicia 



Fdba, Sempervivum, Veronica, etc. . . . 233 



Section II. Rudimentary institutions . . . 237 



(1) Truck system and clearing-house. (2) Corpora- 

 tions and syndicates. (3) Archaic collectivism and 

 modern collectivism. (4) The survival of elective 

 sovereignty in England . . . ' . 239 



Chapter III. Can rudimentary organs or institutions re- 

 develop and assume new functions ? . . 242 

 Section I. Rudimentary organs . . . 243 



1. Animals. Respiratory organs in Birgus latro ; 

 Mesonephric spaces in the higher vertebrates . 243 



2. Plants. Staminodes of Pentstemon . . 244 

 Section II. Rudimentary institutions . . . 245 



Levirat . . . . . - . 245 



PART III. Summary and conclusions . . . 247 



BOOK III 



CAUSES OF DEGENERATIVE EVOLUTION 



PART I. Atrophy of organs and institutions . . .- 251 



Section 1. The factors of atrophy . . . . 251 



(1) Biology (accidental, individual, normal and specific 

 atrophy). (2) Sociology (accidental and normal 



atrophy) ...... 251 



Section II. Causes producing atrophy . . . 260 



Chapter I. Atrophy of organs . . . . . 260 



1. Atrophy from lack of space .. . . ... 261 



