FUNCTIONALLY-CAUSED MODIFICATIONS. 621 



incredible when we recognise the probability that an organism is 

 more or less permeable to undulations propagated by its mole- 

 cules : Rontgen rays giving warrant. If such units throughout the 

 tissues may take in and send out ethereal waves which bring it 

 into rhythmical relations with others of its kind and tend to pro- 

 duce congruity, it becomes, if not conceivable still supposable, 

 that throughout the circulating protoplasm there goes on a con- 

 tinual harmonization of its components a moulding of each by 

 all and of all by each. Should it be said that such a process is 

 too marvellous to be reasonably assumed, the reply is that it is 

 not more marvellous than heredity itself, which, were it not 

 familiar to us, would be thought incredible. 



But as I have said in the place referred to " At last then we 

 are obliged to admit that the actual organizing process transcends 

 conception. It is not enough to say that we cannot know it ; we 

 must say that we cannot even conceive it : " can only conceive 

 the possibility of a suggested interpretation. 



Hence we have to rely upon evidences of other kinds. Among 

 these, some which I think dispose absolutely of the fashionable 

 hypothesis while they harmonize with the opposed hypothesis, 

 have now to be named. That their implication should not have 

 been generally recognized would have seemed to me incompre- 

 hensible were it not that I have myself only now observed this 

 implication. The facts are these : 



" Verlot mentions a gardener who could distinguish 150 kinds of camellia, 

 when not in flower ; and it has been positively asserted that the famous old 

 Dutch florist Voorhelm, who kept above 1,200 varieties of the hyacinth, was 

 hardly ever deceived in knowing each variety by the bulb alone. Hence 

 we must conclude that the bulbs of the hyacinth and the branches and 

 leaves of the camellia, though appearing to an unpractised eye absolutely 

 undistinguishable, yet really differ." (Darwin, Variation of Animals and 

 Plants, cfcc., vol. ii, p. 251.) " 



More recently testimony to like effect has been given by Dr. 

 Maxwell Masters, and has already been quoted by me in a note 

 to 286 in illustration of another truth. He says concerning 

 such variations : 



" To the untrained eye, the primordial differences noted are often very 

 slight ; even the botanist, unless his attention be specially directed to the 

 matter, fails to see minute differences which are perceptible enough to the 



raiser or his workmen These apparently trifling morphological 



differences are often associated with physiological variations which render 

 some varieties, say of wheat, much better enabled to resist mildew and dis- 

 ease generally than others. Some, again, prove to be better adapted for 

 certain soils or for some climates than others ; some are less liable to injury 

 from predatory birds than others, and so on." 



In his Vegetable Teratology, p. 493, Dr. Masters names another 

 fact having a like implication the fact that among seedling 



