•Ryder.] 154 [May 16, 



9. As cytoplasm began to be developed more abundantly there seems 

 to have been developed a tendency for the products of segmentation 

 to cohere. We may therefore distinguish very sharply these two 

 kinds of segmentation as disruptive and coherent. But the greater 

 development of cytoplasm was itself a consequence of cumulative inte- 

 gration, which proceeded so fast that its products could not be converted 

 into nucleoplasm or chromatin with sufficient rapidity so as to be in a con- 

 dition to fall apart as small cells as a consequence of the action of the 

 direct process of fission. The evidence for this is the fact that the nucleo- 

 plasm or chromatin, in higher forms, is derived by constructive metabol- 

 ism from cytoplasm and is the end-product of the latter. 



10. The secondary evolution of a cytoplasmic field led to a process of 

 divergent evolution or in the production of two kinds of cells, the most 

 primitive or ancestral of which was poorly provided with cytoplasm, 

 while the secondary form was provided with a thick cytoplasmic en- 

 velope. 



11. The primitive minute form of cell is to be identified as the asexual 

 one, which afterwards became "male," while the large overgrown type of 

 cell, loaded with cytoplasm and its secondary products, is to be identified 

 as " female" or as a cell on the way towards disruption into male cells, 

 which tendency it still betrays in the process of extrusion of polar bodies. 

 The arrest of this process of fragmentation in the case of such large cells 

 loaded with cytoplasm, led to the evolutiou of the ovum from the sper- 

 matogonium or such a cell as was primarily destined to produce male cells 

 as a result of its further fission. 



12. The male state is therefore the primitive one, and in the prodigious 

 fertility of the male represents the primordial, asexual, flagellate types. 

 The female cell is a secondary and derived form developed after a cyto- 

 plasmic field has been evolved and after cell-aggregates began to become 

 coherent. 



13. This differentiation was primarily due to cumulative integration, or 

 assimilation beyond the current needs of the organism ; the female cells 

 to which this overgrowth was diverted have tended to grow far beyond 

 the average dimensions of the other cells of the body of the parent, and 

 this excessive size is proof that they have in some way lost the power to 

 undergo spontaneous segmentation, except in the case of parthenogenesis. 

 Cumulative integration is consequently responsible for the evolution of 

 the asexual, sexual and parthenogeuetic modes of reproduction. 



14. Ovarian egg and spermatozoon are not homologous ; ova after ex- 

 trusion of polar bodies are the homologues of spermatozoa. Ovarian ova 

 and spermatogonia are, in many cases, exactly homologous. 



15. The expulsion of the polar bodies and detachment of the egg from 

 the parent exhaust its power of continued spontaneous growth except in 

 case of parthenogenesis. 



