205 
Species and other Controversial Points . 
p. 15 of my Ceylon paper (6) are examples of questions of the kind to which 
the reply is always such, and Mr. Ridley judiciously avoids these. I do not 
pretend, and have nowhere pretended, that any modern hypothesis gives a 
proper explanation of adaptation, which at the moment is perhaps the 
greatest difficulty of all ; but there is no doubt that Natural Selection does 
not do it satisfactorily. The how and the why of evolution have yet to be 
worked out, and that work may be prevented from losing itself in one 
or two blind alleys, at any rate, by the light thrown on geographical 
distribution by the present and other researches. 
The bulk of Mr. Ridleys attack on mutation may be answered by 
referring him to the published work of de Vries, which one cannot but infer 
from his paper that he has not read with great care. Throughout his paper 
he gives instances of large changes as infinitesimal variations, and then pro- 
ceeds to kill the case in the summary by saying that the mutation theory is 
not i/i accordance with the facts. 
He quotes the literature of the fertilization of flowers as a case proving 
that specific differences are useful. I myself was one of the very last 
botanists to work seriously at floral mechanisms, good-naturedly chaffed by 
my friends for adhering to a theory (Natural Selection and detailed Adapta- 
tion) which was steadily going the way of all flesh. Having been brought 
up in the strictest Darwinian school, I devoted five years to this subject and 
to other ‘ adaptations’. For this I am now most grateful, for it has shown 
me the Natural Selection position thoroughly from the inside. But as a result 
I can only say that it is very rarely indeed that a specific character can be 
shown to have any importance in this connexion. The plant can sometimes 
make use of a specific character when there, but it did not acquire that 
character because of its usefulness. 
I have now dealt with the chief points of Mr. Ridley’s attack, and may 
go on to point out that he has made no attempt to parry my own, other 
than by bringing up exceptions, which have no bearing on figures of large 
numbers of plants, such as I was dealing with. The attack being upon my 
Ceylon work, I have confined my answer to that, though New Zealand 
would have supplied a much better one. He makes no effort to explain why 
the figures are graduated in opposite directions for endemics and wides ; 
why the Ceylon-Indian species are intermediate in rarity ; why the various 
species show a chain-mail pattern of distribution (6, maps on p. 12) ; why the 
endemics are ‘ dying out ’ in a mechanical way, one family or genus like 
another, whether they have or have not allied wides beside them ; why every 
family and larger genus (especially in New Zealand) shows the same general 
plan of distribution ; why the area in which occur the maximum number of 
wides coincides with that in which occur the maximum of endemics; and 
so on. Nor does he attempt to meet my arithmetical argument against 
