12 Darwin, and after Darwin. 
has supplanted ; and while it usually incorporates the 
main elements of Darwin’s teaching, it still more 
usually comprises gross perversions of their conse- 
quences. All this I shall have occasion more fully 
to show in subsequent parts of the present work ; and 
allusion is made to the matter here merely for the 
sake of observing that in future I shall not pay 
attention to unsupported expressions of opinion from 
any quarter: I shall consider only such as are accom- 
panied with some statement of the grounds upon 
which the opinion is held. And, even as thus limited, 
I do not think it will be found that the following 
exposition devotes any disproportional amount of 
attention to the contemporary movements of Dar- 
winian thought, secing, as we shall see, how active 
scientific speculation has been in the field of Dar- 
winism since the death of Mr. Darwin. 
Leaving, then, these post-Darwinian questions to 
be dealt with subsequently, I shall now begin a 
systematic résumé of the evidences in favour of the 
Darwinian theory, as this was left to the world by 
Darwin himself. 
There is a great distinction to be drawn between 
the fact of evolution and the manner of it, or between 
the evidence of evolution as having taken place some- 
how, and the evidence of the causes which have been 
concerned in the process. This most important 
distinction is frequently disregarded by popular 
writers on Darwinism; and, therefore, in order to 
mark it as strongly as possible, I will effect a com- 
plete separation between the evidence which we have 
of evolution as a fact,and the evidence which we have 
