54 PROLEGOMENA 



and nourishment; protects from frost and drought; and, 

 in every other way, attempts to modify the conditions, in 

 such a manner as to bring about the survival of those 

 forms which most nearly approach the standard of the 

 useful, or the beautiful, which he has in his mind. 



If the fruits and the tubers, the foliage and the flowers 

 thus obtained, reach, or sufficiently approach, that ideal, 

 there is no reason why the status quo attained should 

 not be indefinitely prolonged. So long as the state of 

 nature remains approximately the same, so long will the 

 energy and intelligence which created the garden suffice 

 to maintain it. However, the limits within which this 

 mastery of man over nature can be maintained are nar- 

 row. If the conditions of the cretaceous epoch returned, 

 I fear the most skilful of gardeners would have to give up 

 the cultivation of apples and gooseberries; while,, if those 

 of the glacial period once again obtained, open asparagus 

 beds would be superfluous, and the training of fruit 

 trees against the most favourable of south walls, a waste 

 of time and trouble. 



But it is extremely important to note that, the state 

 of nature remaining the same, if the produce does not 

 satisfy the gardener, it may be made to approach his 

 ideal more closely. Although the struggle for existence 

 may be at end, the possibility of progress remains. In 

 discussions on these topics, it is often strangely forgotten 

 that the essential conditions of the modification, or evo- 

 lution, of living things are variation and hereditary 

 transmission. Selection is the means by which certain 

 variations are favoured and their progeny preserved. 

 But the struggle for existence is only one of the means 

 by which selection may be effected. The endless 

 varieties of cultivated flowers, fruits, roots, tubers, and 

 bulbs are not products of selection by means of the 

 struggle for existence, but of direct selection, in view 



