is commonly brought forward as conclusive; but if you
will take the trouble to inquire into it rather closely, I think you
will find that it is not worth very much. The first question of course
is, Do they thus return to the primitive stock? And commonly as the
thing is assumed and accepted, it is extremely difficult to get anything
like good evidence of it. It is constantly said, for example, that if
domesticated Horses are turned wild, as they have been in some parts of
Asia Minor and South America, that they return at once to the primitive
stock from which they were bred. But the first answer that you make to
this assumption is, to ask who knows what the primitive stock was; and
the second answer is, that in that case the wild Horses of Asia Minor
ought to be exactly like the wild Horses of South America. If they are
both like the same thing, they ought manifestly to be like each other!
The best authorities, however, tell you that it is quite different. The
wild Horse of Asia is said to be of a dun colour, with a largish head,
and a great many other peculiarities; while the best authorities on
the wild Horses of South America tell you that there is no similarity
between their wild Horses and those of Asia Minor; the cut of their
heads is very different, and they are commonly chestnut or bay-coloured.
It is quite clear, therefore, that as by these facts there ought to
have been two primitive stocks, they go for nothing in support of the
assumption that races recur to one primitive stock, and so far as this
evidence is concerned, it falls to the ground.

Suppose for a moment that it were so, and that domesticated races, when
turned wild, did return to some common condition, I cannot see that this
would prove much more than that similar conditions are likely to produce
similar results; and that when you take back domesticated animals into
what we call natural conditions, you do exactly the same thing as if you
carefully undid all the work you had gone through, for the purpose of
bringing the animal from its wild to its domesticated state. I do not
see anything very wonderful in the fact, if it took all that trouble to
get it from a wild state, that it should go back into its original state
as soon as you removed the conditions which produced the variation to
the domesticated form. There is an important fact, however, forcibly
brought forward by Mr. Darwin, which has been noticed in connection with
the breeding of domesti