1 66 THE HISTORY OF CREATION. 



their thick and strong hairs than the individuals of the first 

 generation. If this process is continued for several genera- 

 tions in one and the same locality, there will arise at last 

 such an increase of this characteristic, such an increase of 

 the hairs on the surface of the leaf, that an entirely new 

 species seems to present itself. It must here be observed, 

 that in consequence of the interactions of all the parts of 

 every organism, generally one individual part cannot be 

 changed without at the same time producing changes in other 

 parts. If, for instance, in our imaginary example, the number 

 of the hairs on the leaves is greatly increased, a certain 

 amount of nourishment is thereby withdrawn from other 

 parts; the material which might be employed to form 

 flowers or seeds is diminished, and a smaller size of the 

 flower or seed will then be the direct or indirect consequence 

 of the struggle for life, which in the first place only pro- 

 duced a change in the leaves. Thus the struggle for life, in 

 this instance, acts as a means of selecting and transforming. 

 The struggle of the different individuals to obtain the 

 necessary conditions of existence, or, taking it in its widest 

 sense, the inter-relations of organisms to the whole of their 

 surroundings, produce mutations of form such as are pro- 

 duced in the cultivated state by the action of man's selection. 

 This agency will perhaps appear at first sight small and 

 insignificant, and the reader will not be inclined to concede 

 to the action of such relations the weight wliich it in reality 

 possesses. I must therefore find space in a subsequent 

 chapter to put forward further examples of the immense 

 and far-reaching power of transformation exhibited in 

 natui'al selection. For the present I will confine myself to 

 simply placing side by side the two processes of artificial 



