THE PASSING OF DARWINISM. 



51 



Darwin studied plants and animals — not in the wild state — where 

 species only arise, but under cultivation and domestication, where 

 varieties only appear ; and he perceived that when wild organisms 

 are brought under the skill of man they soon vary, as a rule, from the 

 original forms, generally in many ways ; e.g. the numerous kinds of the 

 cabbage tribe, which has no varieties in the wild state. This is indefinite 

 variation. 



Materials for Natural Selection. — The materials upon which natural 

 selection was supposed to act in wild plants were the so-called " indi- 

 vidual differences." Darwin thus describes them : " The many slight 

 differences which appear in the offspring from the same parents . . . 

 may be called ' individual differences . . . These are of the 

 highest importance for us, for they are often inherited, and they thus 

 afford materials for natural selection to act on and accumulate." * 



But, if we apply Darwin's definition of Natural Selection, it requires 

 the assumption that the majority of the individuals must have " in- 

 jurious," i.e. " inadaptive variations," which cause the death of their 

 bearers. Such is not the case. Individual differences are due to the 

 fact that growth and development are not mathematically exact and 

 the same in every individual. No two peas in a pod are absolutely 

 alike, nor two leaves on a tree. The differences are merely trivial and 

 of no account to the plant, and never mortal. Nor are they of import- 

 ance, as a rule, to the systematic botanist, who merely adds " very 

 variable " if necessary. 



Darwin's Metaphor of a "noble and commodious edifice." — Darwin has 

 given us an imaginary illustration. It may be described as a parable 

 of the process of natural selection, making it quite clear as to his 

 meaning of " indefinite " variations. He says : "If an architect 

 were to rear a noble and commodious edifice, without the use of cut 

 stone [or mortar], by selecting from the fragments at the base of a 

 precipice wedge-formed stones for his arches, elongated stones for his 

 lintels, and flat stones for his roof, we should admire his skill and regard 

 him as the paramount power. Now, the fragments of stone, though 

 indispensable to the architect, bear to the edifice built by him the same 

 relation which the fluctuating variations of each organic being bear to 

 the varied and admirable structures ultimately acquired by its modified 

 descendants. . . . The shape of the fragments of stone at the base of 

 our precipice may be called accidental, though the shape of each depends 

 upon natural laws, on the nature of the rock, on the lines of deposition 

 or cleavage, &c." f A few observations will show the total inadequacy 

 of this metaphorical illustration. 



The indefinite variations in the shapes of the stones bear no natural 

 relationship to their use for the architect, whereas every alteration 

 of structure in a plant developed under changed conditions of life is 

 itself an adjustment to suit the plant in its varying. 



Secondly, what takes the place of the architect in the organic 



* Origin &c. 6th ed. p. 34. 



| Variation &c. vol. ii. p. 430. 



E 2 



