CHAPTER XVII 



CONSIDERATIONS ON HEREDITY 



Since we restrict ourselves in this Part of the biography to the 

 more purely botanical subjects which had Beijerinck's interest, 

 we shall not discuss herein his very important and detailed studies 

 on the variabihty and the mutabihty of microbes. Yet we may not 

 pass over this subject completely in the survey of his botanical 

 work, since this work also throws hght on heredity in general, and 

 the phylogenetical development in the plant kingdom, an aspect which 

 Beijerinck himself has emphasized repeatedly. 



On the memorable date of September 29th, 1900, HuGO de Vries 

 gave a lecture bef ore the Kon. Akademie van Wetenschappen in 

 Amsterdam, which was to become of historical significance. It was 

 entitled "On the origin of new species of plants", and therein were the 

 first reports of his experiments carried out with the descendants of 

 Oenothera Lamarckiana, the seed of which he had gathered from the 

 field. In this lecture, for the first time, the main lines of the "mutation 

 theory" were faintly outlined. 



As soon afterwards as Saturday October 27th of that year there 

 foliowed a lecture by Beijerinck "On different forms of heredity 

 variation of microbes" i) which he began with these words: "The 

 interesting lecture of Professor HuGO de Vrïes gave at the last 

 meeting of the Academy on the origin of new forms in higher 

 plants, induces me to draw attention to some observations regarding 

 the same subject, in microbes". Beijerinck remarks then that, 

 with microbes, it is easier to start from one individual in the making 

 of cultures, that in these cultures many generations succeed each other 

 quickly, that in this case, more easily than with higher plants, large 

 numbers of individuals can be surveyed at one time, and that with 

 many microbes the mutability is great, making them especially 

 suitable for the study of heredity. 



It is certainly tempting to cite here from this lecture, but the writer 

 feels that he must restrict himself to one single citation. One of Beije- 

 rinck's paradoxes was the following: the most important Communica- 

 tions of a scientific paper are to be found in the footnotes of the treat- 

 ise. As a matter of fact, BeijeriKck's point of view with respect to 



i) Proceedings of the Section of Sciences, Kon. Akad. v. Wetenschappen Am- 

 sterdam 3, 352-365, 1900 {Verzamelde Geschriften 4, 37-47). 



