Independence of Hereditary Peculiarities 147 



"Experiments upon the production of varieties teaches 

 us further that nearly every peculiarity can vary inde- 

 pendently of the others. Many varieties in fact diverge 

 from their stock form by only a single character; for in- 

 stance the white blooming variety of a species with red 

 flowers. In the same way the villosity, the armanent of 

 spines or thorns, the green color of leaves, each of these 

 characters can vary by itself and can even disappear en- 

 tirely, and all the other hereditary properties remain 

 perfectly unaltered." 



It follows that: "The hereditary anlagen, of which 

 the hereditary peculiarities are the visible signs, are inde- 

 pendents units which may have had their origin at differ- 

 ent epochs, and which may also be lost independently. 

 They are miscible with one another in almost all propor- 

 tions, since each peculiarity can pass through all inter- 

 mediate degrees from its complete absence to its greatest 

 development." 



"Independence and miscibility, these are the essential 

 properties of the hereditary anlagen of all organisms." 121 



Quite similar to this argument of DeVries is that of 

 Weismann in favor of his preformation or of preformistic 

 germs in general : "It is impossible for one part of the 

 body to vary independently of the others, and for these 

 variations to be hereditary, if it is not represented in the 

 germ plasm by a special particle, a variation of which in- 

 duces a corresponding variation of the part in question. 

 If this were represented, together with other parts of the 

 body, by a single particle of the germ plasm, then a 

 change of this latter would have as its consequence the 

 variation of all the parts which are determined by it. In 



121 De Vries : Intracellulare Pangenesis. Jena, Fischer, 1889. P. 

 MI. 17, 32, 33- English Translation by C. Stuart Gager. Open 

 Court Publishing Co. 1910. 



