2;^6 THE HISTOHY OF CREATION. 



People who, by means of Banting's system, at present so 

 popular, wish to become thin eat only meat and eggs — no 

 bread, no potatoes. The important variations that can be 

 produced among cultivated plants, solely by changing the 

 quantity and quality of nourishment, are well known. The 

 same plant acquires an altogether different appearance, 

 according as it is placed in a dry and warm place, exposed 

 to the sunlight or placed in a cool damp spot in the shade. 

 Many plants, if transferred to the sea shore, get in a short 

 space of time thick, fleshy leaves, and the same plants 

 placed in a particularly dry and hot locality get thin hairy 

 leaves. All these variations arise directly from the cumu- 

 lative influence of changed nutrition. 



But it is not only the quantity and quality of the articles 

 of nutrition which aflect and powerfully change and trans- 

 form the organism, but it is affected also by all the other 

 external conditions of existence, above all by its nearest 

 organic surroundings, the society of friendly or hostile 

 organisms. One and the same kind of tree develops itself 

 quite differently in an open locality, where it is free on 

 all sides, and in a forest where it must adapt itself to its 

 surroundings, where it is pressed on all sides by its 

 nearest neighbours, and is forced to shoot upwards. In 

 the former case, the branches of the tree spread widely out ; 

 in the latter, the trunk extends upwards, and the top of 

 the tree remains small and contracted. How powerfully 

 all these circumstances, and how powerfully the hostile or 

 friendly influence of surrounding organisms, of parasites, 

 etc., affect every animal and every plant, is so well known, 

 that it appears superfluous to quote further examples. The 

 change of form, or transformation which is thereby effected, 



