THE PROBLEIM OF ACTIVATION 267 



viz., specificity, irreversibility, and activation, for these 

 are inseparable. The penetration of the spermatozoon 

 and the union of the germ nuclei are results of these 

 primary factors of the fertilization reaction, and they 

 constitute, therefore, secondary problems, even though 

 from a teleological point of view they represent the 

 essence of the entire process. 



It is hoped that the writer's fertilizin hypothesis 

 presented in various places in this book at least supple- 

 ments other theories of activation and points the way 

 to a more inclusive theory that shall comprise all the 

 main aspects of fertilization. 



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Allyn, Harriet M. 



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Bataillon, E. 



1909. "L'impregnation heterogene sans amphimixie nucle- 



aire chez les-amphibiens et les echinodermes," Arch. 



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 i9iO(?. "L'embryogenese complete provoquee chez les am- 



phibiens par piqure de I'oeuf vierge, larves parthc- 



nogenetiques de Rami fusca,^' Com pics rcndus de 



I'Acad. de. Sci., T. 150. 

 1910/;. Le probleme de la fecondation circonscrit par 



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