CONTENTS XI 



LECTURE X 

 Heredity 



PAGE 



1. The Hereditary Effects of the Spermatozoon and Egg — The Prevailing Influence 



of the Egg in the Early Stages of Development — Merogony — Toxicity of 



the Blood of Forms not closely Related — Mendel's Experiments . . .179 



2. The Determination of Sex and the Secondary Sexual Characters . . . .186 



3. Egg Structure and Heredity . . ........ 191 



LECTURE XI 

 On the Dynamics of Regenerative Processes 



1. Sachs's Hypothesis of the Formation of Organs 199 



2. H eteromorphosis and Regeneration in Tubularia 201 



3. Regeneration in an Actinian ( Cerianthus membranaceus) ..... 207 



4. Regeneration and Heteromorphosis in Planarians 210 



5. On the Influence of the Central Nervous System upon Regeneration and on Phe- 



nomena of Correlation in Regeneration 213 



5. The Effect of Some External Conditions upon Regeneration and the Transforma- 

 tion of Organs 217 



7. The R61e of Reversible Processes in Phenomena of Regeneration — The Distribu- 

 tion of the Power of Regeneration in the Animal Kingdom .... 218 



LECTURE XII 

 Concluding Remarks 223 



INDEX 227 



