68 The Unity of the Organism 



fundamental as hereditary substance? Surveying as we 

 have the whole field of organic propagation, including the 

 process in unicellular organisms as well as in multicellular, 

 and sexless as well as sexual methods of reproduction, and 

 taking the facts as they actually present themselves, it 

 seems as though but one answer to this inquiry is possible: 

 The substances included under the generic term cytoplasm 

 are the more fundamental and primitive. 



The only possible way of escaping this conclusion is by 

 excluding from the conception of heredity the vast majority 

 of developmental phenomena presented by unicellular organ- 

 isms and by monogenic propagation in multicellular organ- 

 isms. As our examination of these provinces revealed, such 

 exclusion is exactly what the chromatin dogma of heredity 

 has undertaken, implicitly or explicitly, to fix upon biology. 

 The utter unwarrantableness of this undertaking was made 

 sufficiently obvious, we may assume, by the examination ; 

 so we need spend no time on that now. All that is necessary 

 is to remind ourselves vividly of the main positive outcome 

 of the examination : Heredity is a universal phenomenon of 

 the living world. It is coextensive with organic propagation 

 and development, while "carrying heredity" by chromo- 

 somes is, according to the evidence, very far from a uni- 

 versal phenomenon. It is a long way from being coex- 

 tensive with organic propagation and development. We 

 may, consequently, proceed in our quest of a more rational, 

 more consistent, more satisfactory conception of the purely 

 operative side of producing hereditary structures. Pur- 

 suing the quest, we remind ourselves of having found that 

 only the most meager observational evidence is afforded by 

 the protophyta and protozoa, and by monogenic metaphyta 

 and metazoa, that chromatin is hereditary substance, while 

 these organisms afford an overwhelming mass of such evi- 

 dence that cytoplasm is hereditary substance. 



But if in the lower, more primitive moiety of the organic 



