CHEMICAL PHENOMENA IN LIFE 



research work has not been carried out very often, 

 but the few experiments which have already 

 been made render it most probable that Quetelet's 

 law holds for chemical properties as well as for 

 morphological characteristics. It would be com- 

 paratively easy to examine the amount of acid 

 contained in leaves, the amount of starch or of 

 protein which is contained in one individual 

 in a great number of cases in order to confirm 

 the results mentioned above. No research work 

 at all has been done to determine the velocity of 

 chemical processes or reactions in a great number 

 of single individuals. Data without any difficulty 

 could be worked out on the velocity at which starch 

 or protein disappear from germinating seeds or on 

 the intensity of respiration in many individuals 

 which live under exactly the same conditions. It is 

 difficult to say what results would be thus obtained. 

 In any case such research work is highly desirable. 

 The second kind of variation takes place sud- 

 denly, eruption-like, and culminates in the pro- 

 duction in single individuals of quite different 

 characteristics which are markedly inheritable. 

 Since De Vries' famous book on these phenomena, 

 we call such variations Mutations. Chemical 

 mutations are widely spread and well known. In 

 horticulture and agriculture many new mutations 

 which were kept on account of their valuable 

 chemical properties have in the course of time 

 been isolated. Fruits, containing an extraordinary 



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