:'• 





?ii 



CONTENTS. IX 



CHAPTEE XIY. 



Mutual Affinities of Organic Beings : Morphology : 

 Embryology : Rudimentary Organs. 



Classification, groups subordinate to groups — Natural system — Eules 

 and difficulties in classification, explained on the theory of descent 

 with modification — Classification of varieties — Descent always used 

 in classification — Analogical or adaptive characters — Affinities, 

 general, complex, and radiating — Extinction separates and defines 

 groups — Morphology, between members of the same class, between 

 parts of the same individual — Embryology, laws of, explained by 

 variations not supervening at an early age, and being inherited at a 

 corresponding age — Kudimentary organs ; their origin explained — 

 Summary *.. Page 363-403 



CHAPTEE XY. 



Recapitulation and Conclusion. 



Recapitulation of the objections to the theory of Natural Selection — 

 Recapitulation of the general and special circumstances in its favour 

 — Causes of the general belief in the immutability of species — 

 How far the theory of Natural Selection may be extended — 

 Effects of its adoption on the study of Natural History — Con- 

 cluding remarks .. 404-429 



Glossary of Scientific Terms 430 



Index 443 



