194 PRESENT-DAY RATIONALISM 



Weismann says 'acquired characters cannot be transmitted at 

 all,' every day in Egypt contradicts this opinion, and the fact 

 that ' species of plants in Egypt have remained unchanged for 

 thousands of years ' proves only that the climatic conditions 

 of Egypt have remained all the time unchanged. 



" On the other hand, seeds of ' gignut,' a variety of Cannabis 

 sativa from Europe, produces by the third generation the true 

 Cannabis sativa yarn. Black mustard, Brassica nigra, is trans- 

 formed into the endemic B. bracteolata^ Mayer, in the second 

 generation. Also the thick-rooted celery assumes in the first 

 year the much foliated form with a thin root-stock, like the 

 summer spontaneous form of Egypt. 



" I have had myself the opportunity of substantiating these 

 facts several times. 



" On the other hand, it must be proved that external influ- 

 ences are acting in other ways upon the germ-plasm than 

 upon the somato-plasm. All action in Nature is based upon 

 chemical and physical forces — so that really the constitution 

 of the pretended germ-plasm must be different from that of the 

 somato-plasm." 



