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X. A Possible Mode of Inheritance of Adaptive Characters. 

 By Cecil B. Ckampton, M.B., CM. 



(Received lOtli March; read 27th March 1905.) 



In a former paper to the Society, I suggested that plants 

 and animals have diverged in their evolution, owing to a 

 difference in their anabolism in relation to the stability or 

 instability of its products, and that this stability increases 

 in plants until it destroys the vitality of the cell, while in 

 animals the instability increases until katabolism gets the 

 upper hand of anabolism, with resulting death (1). This 

 does not refer to somatic death, or death of the organism 

 as a whole, but rather to death of the individual cells, which 

 takes place throughout the life of the animal or plant, and 

 only indirectly leads to somatic death, through a want of 

 mutual co-operation in the different tissues. One ideal form 

 of anabolism is growth without differentiation, and which 

 there is no reason to think would not continue indefinitely 

 if no specialisation took place. Nearest this ideal type is 

 that in which parts or cells retain their powers of giving 

 rise to a new individual, and this must differ for the scale of 

 specialisation arrived at by each form. A gradual divergence 

 from this type is seen in those cells which retain some 

 powers of regeneration, through those in which cell division 

 is still found, to the extreme cases in which all powers of 

 this kind have been lost, and which, at the same time, 

 usually show the greatest degree of specialisation. 



As a result of fertilisation in higher plants, a meristem 



