CHEMICAL PHENOMENA IN LIFE 



since the progeny of bitter or sweet almonds, re- 

 spectively, invariably show their peculiar char- 

 acteristic. Consequently the characteristic of 

 producing amygdalin depends on the nuclei of 

 the sexual cells. Generally, we speak of heredity 

 only when sexual processes are involved, and the 

 properties of one generation are transferred to the 

 following generations. In plants, however, it is 

 possible to take the conception of heredity in a 

 wider sense. Sensu stricto a sexual cell with its 

 properties is a part of the parental organism which 

 is separated from the latter and is beginning an 

 independent life. For heredity I think we must 

 not lay too much stress upon this circumstance, 

 and it does not matter whether the transferring of 

 parental properties takes place among cells which 

 remain connected or not. When in a growing 

 branch the young part acquires its properties from 

 the adult part, this process is done by cell cleavage, 

 each cell transferring its characteristics to its 

 daughter-cells. We may consequently here also 

 speak of phenomena of inheritance, and we shall 

 distinguish them as Asexual Inheritance. The 

 term Inheritance implies that the transferring of 

 characteristics takes place continually from genera- 

 tion to generation. But it is not necessary for the 

 characteristics to be apparent. Hybrids often do 

 not show their characteristics in an intermediate 

 form between the parental forms, but entirely 

 resemble in a certain respect one of their parents. 

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