CHAPTER III. 

 THE PROBLEMS OF GAMETIC CONSTITUTION. 



INTRODUCTION. 



Knowledge of the gametic constitution of organisms has been one of the 

 desert spots in biology, because there has been, up to recent times, no adequate 

 working hypothesis for use in investigation, with the result that there has been 

 endless interpretation and profitless speculation that has served more to con- 

 fuse than to advance the analysis of the gametic constitution and the behavior 

 of characters in genetic lines of descent. Darwin's provisional hypothesis of 

 pangenesis, and the subsequent conceptions that were the natural outgrowth of 

 it, lead only to controversy, interpretation, and plausibilities, and were not 

 capable of use as working hypotheses in experimentation. The Galtonian 

 hypothesis stated only the results of a statistical blending of the data and 

 arrived at no analytical results, nor can the hypothesis be utilized in the 

 orientation of any critical experimental analysis. The rediscovered work of 

 Mendel and the neo-Mendelian developments that have taken place in the past 

 decade, especially the advances made by Cuerrot, have produced, at the least, 

 a useful working hypothesis. 



In the course of this investigation I have had abundant opportunity to test 

 the two current hypotheses, without prejudice to either. The inherent defects 

 in the Galtonian hypothesis were early apparent ; the early dogmatic assertions 

 with regard to the Mendelian principles, the rabid partisanship of many of its 

 adherents, unfortunately gave it the setting of a cult, and led, naturally, to 

 suspicion of its principles. Both of the hypotheses were put to severe test 

 through the course of this investigation. 



The net result of the severe tests was the complete failure of the Galtonian 

 hypothesis in all respects and at every point and the demonstration that the 

 principles of Mendel were true in their broader aspects when stripped from the 

 encumbering conceptions of " fixed units " and Weismannism. The conceptions 

 of the separateness of manifestation of "characters" as the result of the inter- 

 action of specific agents in the germinal material, the capacity of these for 

 transfer or metathesis, and the random metathetic distribution of characters 

 into different classes of gametes, were put to every sort of test that I could 

 devise, but in no instance, thus far, have I been able to satisfy myself that tests 

 made have in any manner been at variance with the real principles, and, in short, 

 have in every respect throughout confirmed them and in some directions carried 

 the investigation farther than friendly investigations in its support would have 

 done. In the effort to find characters that " did not Mendelize," meaning the 

 fact that they were not definite in manifestation and were not able to " segre- 

 gate " but blended in crossing, I have had no success. In these cases on further 

 testing I have always found either conditions in the medium, in the organism, 

 or associations of the character with others that, when worked out, showed 

 entire agreement with the principles of factorial constitution and operation. 

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