68 Tiiality and Organization of Protoplasm. 



in so far as the constitution of the adult organism is rigorously predeter- 

 mined in the chemical constitution of the germ. But the adult organ- 

 ism is nowise structuarly pre-established in the germ in the sense of 

 Bonnet, Haller, Eoux, Weismann, and their more or less faithful fol- 

 lowers; nowise in the sense of the old and new theory of structural pre- 

 formation. It is not as Eoux declares the merging into visibility of 

 latent pre-existing differences. It is the merging into visibility of newly 

 arising differences. Ontogenetic development takes place through such 

 epigenesis as advocated by Wolff and Baer; epigenesis, namelj'', in the 

 sense that morphological structures merge into visible existence as out. 

 and out new formations, one stage of structural development serving as 

 foundation for the next stage. The development of the germ into an adult 

 organism is chemically evolutional, but structurally or morphologically 

 epigenetic. In ontogenetic evolution the successive stages of chemical 

 reintegration, though evolutionally predetermined, represents a forma- 

 tive process by w^hich the structures of the adult organism are newly 

 reproduced. 



True phyletic genesis consists in the complete new formation of what 

 is being for the first time produced, and not merely generically repro- 

 duced. Creative increments of organic development give here rise to 

 progressively higher forms of beings, and the corresponding reproduc- 

 tive potentialities of their germs are newly acquired, and represent not 

 merely a pre-existing fund of previously established dispositions. 



SEGMENTATION. 



The disentanglement of the factors that condition the segmentation 

 of the germ-plasm, and therewith the normal "prospective import" of 

 the successive blastomeres, is no easy task. To rightly attack the prob- 

 lem one has above all to discard the misleading notion, that what we 

 have here before us as an e^g represents anything in the remotest degree 

 resembling a cell, or elementary organism, as scientifically defined. The 

 germ-plasm is nowise an autonomous elementary organism, which mul- 

 tiplies by self-division. Its divisions are essentially a_ nianifestation of 

 unfolding potentialities, in which all , ensuing formative, evolution is 

 rigorously predetermined. An egg-cell, instead of being an autonomous 

 elementary organism, represents^ on the contrary, the potential concen- 

 tration of all the accumulated results of phyletic elaboration. This 

 should be quite obvious without further discussion, though, strange to say, 

 most zoologists still adhere out of traditional prejudice to the cell-theory, 

 which has come to be highly obstructive to biological progress. 



But liow do tlie two first blastomeres come each potentially to repre- 

 sent one entire half-embryo? It has been shown that the living sub- 

 stance in its earliest fonnative manifestation, as an amoeboid projection, 

 or so-called pseudopodium, assumes by force of its intrinsic constitution 

 and its vital motility a symmetrically bilateral form. And when the en- 

 tire living substance of an amoeboid being comes to constitute one single 



