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acquitted without much consultation on the part of the jury, — in fact, 
the verdict would be “Not proven.” 
This, as it appears to us, is precisely how the question of the “ Origin 
of Species ” stands at present. The chief obstacle which now stands in the 
way of the acceptance of Mr. Darwin’s theory is, that he has not been 
able to create a new species by artificial selection. Although he has effected 
in a few years an approach to that end which, in nature , would probably 
have occupied ages ; and although he and others have produced 150 
varieties (of pigeons), differing widely from one another, yet in every 
case these varieties have been fertile with one another, and there has been 
no approach to sterility.* Neither can it be shown that “ natural selection ” 
is anything more than a probability, nor that, in nature, species have been 
found to cross, excepting (as a general rule) with sterile results. 
This is of course the chief interpretation of our supplementary evidence 
concerning the height of the window from the garden. And now as 
regards our author’s special pleading. If any one thinks that we have 
overstated or burlesqued this part of the subject, let him turn to 
the text,+ and there he will find how ingeniously, nay, how plausibly, 
the author disposes of the difficulty in question, really the crucial test. 
The author’s argument is practically as follows. We will test the validity 
of Mr. Darwin’s theory by a three-fold process : — 
1st. We will ask : Do the supposed causes of the phenomena exist in 
nature ? 
The answer is decidedly affirmative. Atavism, variability, and con- 
ditions of existence analogous to those which are operative in artificial 
breeding, do exist in nature. 
2nd. Are these causes competent to produce new species ? 
Answer, not quite so confident. Races may be thus produced, and it 
would be very difficult to explain many of the phenomena connected with 
species in any other manner. 
(Is it possible to reach the ground from this window? 
Yes; a friend of mine has succeeded in reaching the projecting ledge; 
besides, there are many circumstances connected with the theft — dirty 
hands, &c., which could not be otherwise explained.) 
But I grant freely that, so far, it has been found impossible to produce 
infertile hybrids by artificial breeding, and being a disinterested critic , I 
feel bound to confess that it is a serious barrier to the acceptance of the 
view's which I advocate. Still the phenomena of sterility are very capricious. 
The crucial test may be successfully applied, and unless you can prove it to 
be impossible you have no right to say it cannot be effected, and to deny 
the accuracy of my theory, which assumes that this is the normal method 
by which new species have been produced. 
(There is no knowing whether some day or other a person may not 
manage the leap from the ledge to the ground ; and unless you can prove 
that it is an absolute impossibility, you have no right to say that my 
* This will be more fully explained hereafter. 
t P. 137. 
