VIII CONTENTS. 



CHAPTER IV. 



PAGE 



Relations of the Animal-Sentient (Cerebral) Forces and of the 



Vis Nervosa to each other ..... 275 



Sect. 1. — On the Substitution of Nerve-Actions for Sentient Actions . 275 



II. — On the Substitution of Sentient Actions for Nerve-Actions . 299 



III. — The Reciprocal Connection of the Animal-Sentient (Cerebral) Forces, 



with the Vis Nervosa in the Natural State . . . 302 



PART III. 

 ANIMAL NATURE CONSIDERED AS A WHOLE. 



Introduction . . . . . . . 308 



CHAPTER I. 

 On Animal Nature in General .... 309 



CHAPTER II. 

 The principal Genera of Existing Animals . . .317 



CHAPTER III. 

 On the Origin of Animal Nature .... 327 



CHAPTER IV. 

 On Animal Life ...... 330 



CHAPTER V. 

 The System of the Forces of Animal Life . . . 337 



CHAPTER VI. 

 On Old Age and Death ..... 354 



e:nd or contents to vkzku's 'I'mncirLiis oi' physiology.' 



