Evidence -from. Metazoan Germ-Cells 



(c) Critical Examination of Conklin's Interpretation 



One is struck at the outset of a critical examination of 

 these sentences by the fact that what is claimed is that ob- 

 servations have been made whereby a method is "suggested 

 of harmonizing the facts of cytoplasmic localization with 

 the nuclear inheritance theory" ; and that this suggested 

 harmonization of sucli localization with the "nuclear in- 

 heritance theory" (not "chromatinic inheritance theory" 

 be it noticed) is the final count in a mass of evidence which 

 "practically amounts to a demonstration" that the "chro- 

 mosomes are the seat of the inheritance material." 



In other words objective facts which are only suggestive 

 of a conclusion as touching the inheritance role of the whole 

 nucleus rise to the demonstrational level as touching the 

 same role of very small parts of the nucleus. 



The method by which this particular piece of logical 

 sleight-of-hand is performed is easy to see, for though va- 

 ried to meet the exigencies of the special case, it follows the 

 general scheme of elementalistic interpretation with which 

 we have become familiar. In the first place, the fact that 

 the observations furnish very little if any direct evidence 

 that the chromosomes cause the cytoplasmic flowing and 

 localization is made innocuous as evidence against the chro- 

 mosome dogma by assuming that the flowing and localization 

 do not themselves come under heredity. That such an as- 

 sumption is implied, in the argument seems certain from 

 the fact that Conklin did not consider that the general 

 theory of chromosomes as the bearers of heredity which he 

 had espoused made it incumbent upon him to take cognizance 

 of the fact that he himself had in reality testified that 

 portions of the nucleus other than chromosomes are the 

 seat of inheritance material. We have here another and a 

 very notable case of shielding a prevalent theory by defini- 

 tion ; that is, of shutting relevant but inimical facts away 



