X Contents 



FAOI 



XVI. Analysis of the Original Method of Producing Arti- 

 ficial Parthenogenesis by Hypertonic Solutions 

 Alone - - - - 159 



XVII. Membrane Formation and Cytolysis - - - 173 



XVIII. The Fertilizing Effect of Foreign Blood and Foreign 



Cell Extracts 191 



XIX. The Fertilizing Effect of Sperm Extract - - - 201 



XX. The Mechanism of the Formation of the Fertilization 



Membrane 207 



XXI. Is Development of the Sea-Urchin Egg Possible with- 

 out Membrane Formation or without the Second 

 (Corrective) Factor? 219 



XXII. The Action of the Spermatozoon upon the Egg. I. 



Heterogeneous Hybridization . - - . 225 



XXIII. The Action of the Spermatozoon upon the Egg. II. 



The Combination of Artificial Parthenogenesis and 

 Fertilization with Sperm in the Same Egg - - 233 



XXIV. Conditions for the Maturation of the Egg - - 243 

 XXV. Artificial .Parthenogenesis in the Eggs of the Starfish - 249 



XXVI. Artificial Parthenogenesis in the Eggs of Annelids' - 257 



XXVII. Experiments with the Eggs of Molluscs - - - 267 



XXVIII. Artificial Parthenogenesis in the Eggs of Frogs - - 271 



XXIX. Artificial Parthenogenesis in Plants - - - - 277 



"'■■ XXX. Preservation of the Life of the Egg by the Act of 



Fertilization - - - - - 281 



^ XXXI. Artificial Parthenogenesis and Heredity - - . 291 



XXXII. Can an Embryo Develop from a Spermatozoon 7 - 303 



