i895 INDIVIDUAL VARIATIONS. 389 



suppose that they are like plants, in that the varying features of their 

 structure, that is of numerous individual crabs respectively, were 

 simply due to growth and development being never exactly alike in 

 any two, and, therefore, not to be trusted as hereditary. It is not, 

 therefore, that any crabs are " destroyed " in consequence of slight 

 abnormalities or deviations from the average form, but that their 

 variations are not necessarily reproduced in their offspring, which 

 might vary slightly again, either towards the average form or in some 

 other way. Hence, I do not quite agree with the writer in saying: 

 " It is clear from the data that there must be a special death-rate 

 among crabs which have a certain deviation from the normal in the 

 case of the frontal breadth, and that there is no special death-rate 

 among crabs with deviations of the right dentary margin." Without 

 evidence, I would suggest the above interpretation as probably the 

 correct one, as none of the 7,000 specimens appear to have been 

 actually malformed, or more sickly or more likely to die sooner than 

 the rest, or less likely to produce healthy offspring. 



To return to the origin of C alt ha minor. It might, of course, be 

 said that all the " indefinite," ill-adapted variations, which may be 

 supposed to have put in an appearance on the mountains, together 

 with the few adaptive individuals, have all died out ages ago ; and 

 this could neither be proved nor disproved to have been the case. 

 But many experiments have shown that if plants, or even half of an 

 individual plant, or their seeds, be taken from lowlands and planted 

 on alpine regions, all those that change their structures, at once 

 begin to assume more or less the same anatomical and morpho- 

 logical characters as the plants normally growing on highland regions. 

 On the other hand, they never produce any " indefinite," much less 

 any "injurious" variations, as has been so completely proved by 

 Messrs. Bonnier, Flahault, and others. We may look, but we shall 

 look in vain for them ; for there are no facts in support of the existence 

 of innumerable indefinite variations for the benefit of Natural 

 Selection, other than those due to growth and development ; but these, 

 as in the case of Caltha, supply no sufficient material for Natural 

 Selection ; as a rule they are " non-specific," according to Mr. 

 Wallace, and I entirely agree with him. 



On the other hand, there is an overwhelming amount of evidence, 

 both from nature and experiment, that self-adaptation to a new 

 environment is the true and only method of evolution, without any aid 

 from Natural Selection at all. 



The point I would, therefore, emphasise is, that Professor Weldon's 

 statistics among crabs (and cows, horses, pigs, dogs, and human 

 beings themselves, would readily supply analogous ones), as well as 

 similar data among plants, prove nothing of themselves, beyond the 

 patent fact that they are all due to the irregularities of nutrition, and 

 are, consequently, the " inexact " results of the laws of growth and 

 development of organic beings. Whenever, however, any one or 



