x Contents PART in 



PART III 



THE FORMS OF ANIMAL LIFE 



CHAPTER XI 



THE ELEMENTS OF STRUCTURE 



i. The resemblances and contrasts between plants and animals 2. 

 The relation of the simplest animals to those which are more com- 

 plex 3. The parts of the animal body , . Pages 167-183 



CHAPTER XII 



THE LIFE-HISTORY OF ANIMALS 



i. Modes of reproduction 2. Divergent modes 3. Historical 4. The 

 egg-cell or ovum 5. The male-cell or spermatozoon 6. Matura- 

 tion of the ovum 7. Fertilisation 8. Segmentation and the first 

 stages in development 9. Some generalisations : the ovum 

 theory, the Gastrcea theory, fact of recapitulation, organic con- 

 tinuity . . . . . . 184-203 



CHAPTER XIII 



THE PAST HISTORY OF ANIMALS 



i. The two records 2. Imperfection of the geological record 3. 

 Palceontological series 4. Extinction of types 5. Various diffi- 

 culties 6. Relative antiquity of animals . . 204-209 



CHAPTER XIV 



THE SIMPLEST ANIMALS 



i. The simplest forms of life 2. Survey of Protozoa 3. The common 

 Amceba 4. Structure of the Protozoa 5. Life of Protozoa 6. 

 Psychical life of the Protozoa 7. History of the Protozoa 8. Rela- 

 tion to the earth 9. Relation to other forms of life 10. Relation 

 to man .... 210-221 



