CONTENTS XI 



PAGE 



Review of Groups in which Budding occurs. Relation of Budding to 



Regeneration 149 



Autotomy 150 



Theories of Autotomy 155 



CHAPTER IX 

 GRAFTING AND REGENERATION 



Examples of Grafting in Hydra, Tubularia, Planarians, Earthworms, Tadpoles . 159 



Grafting Pieces of Organs in Other Parts of the Body in Higher Animals . 178 



Grafting of Parts of Embryos of the Frog 182 



Union of Two Eggs to form One Embryo 188 



CHAPTER X 

 THE ORIGIN OF NEW CELLS AND TISSUES 



Origin of New Cells in Annelids 190 



Origin of the New Lens in the Eye of Salamanders 203 



The Part played by the " Germ-layers " in Regeneration .... 207 

 The Supposed Repetition of Phylogenetic and Ontogenetic Processes in 



Regeneration 212 



CHAPTER XI 

 REGENERATION IN EGG AND EMBRYO 



Introduction 216 



Regeneration in Egg of Frog 217 



Regeneration in Egg of Sea-urchin ........ 228 



Regeneration in Other Forms : Amphioxus, Ascidian, Ctenophore, Snail, 



Jelly-fish, Fish 236 



CHAPTER XII 

 THEORIES OF DEVELOPMENT 



Theories of Isotropy and of Totipotence of Cells 242 



Theory of Qualitative Division of Nucleus 243 



Theory of Equivalency of Cells 244 



Theory of the Organized Structure of the Protoplasm 246 



Theory of Cells as Units 250 



