ORIGIN OF 8PECIE8 225 



Again: 



"I am inclined to believe that the direct and 

 essential effect of the spermatozoon and the 

 methods of artificial parthenogenesis is the 

 starting of a definite chemical process, and that 

 the formation of astrospheres is only a secondary 

 effect of this. It is in harmony with this idea 

 that the process of segmentation in the case of 

 artificial parthenogenesis is entirely regular, and 

 does not differ from that of fertilized eggs, pro- 

 vided that the right concentration and time of 

 exposure are selected. "^^ 



It must be noted that in order that an egg may be 

 fertilized, or activated, either by a spermatozoon or 

 artificially, it must be in the specific condition de- 

 scribed as "ripe." Loeb describes,^^ in the case of the 

 egg of the starfish, that the nucleus must have become 

 dissolved in the protoplasm. 



It has been established, then, in numerous in- 

 stances that in fertilization the life-activity of the 

 spermatozoon can be duplicated by artificial means. 

 As Loeb shows: "The objection raised that the 

 phenomena are limited to a few species soon became 

 untenable since it has been possible to produce arti- 

 ficial parthenogenesis in the eggs of plants {Fucus 



*i Dynamics of Living Matter, 172, 176, 178. 

 « Ibid., 172. 



