ture which the species has passed
through in its evolution. Whether this statement will bear a critical
verbal examination I will not now pause to inquire, for it is more
important to determine whether any independent facts can be alleged in
favour of the theory. If it could be shown, as was stated to be the case
by L. Agassiz, that ancient and extinct forms of life present features
of structure now only found in embryos, we should have a body of facts
of the greatest importance in the present discussion. But as Huxley (See
Huxley's "Scientific Memoirs", London, 1898, Vol. I. page 303: "There is
no real parallel between the successive forms assumed in the development
of the life of the individual at present, and those which have appeared
at different epochs in the past." See also his Address to the
Geological Society of London (1862) 'On the Palaeontological Evidence of
Evolution', ibid. Vol. II. page 512.) has shown and as the whole course
of palaeontological and embryological investigation has demonstrated, no
such statement can be made. The extinct forms of life are very similar
to those now existing and there is nothing specially embryonic about
them. So that the facts, as we know them, lend no support to theory.

But there is another class of facts which have been alleged in favour
of the theory, viz. the facts which have been included in the
generalisation known as the Law of v. Baer. The law asserts that embryos
of different species of animals of the same group are more alike
than the adults and that, the younger the embryo, the greater are the
resemblances. If this law could be established it would undoubtedly be
a strong argument in favour of the "recapitulation" explanation of the
facts of embryology. But its truth has been seriously disputed. If it
were true we should expect to find that the embryos of closely similar
species would be indistinguishable from one another, but this is
notoriously not the case. It is more difficult to meet the assertion
when it is made in the form given above, for here we are dealing with
matters of opinion. For instance, no one would deny that the embryo of a
dogfish is different from the embryo of a rabbit, but there is room for
difference of opinion when it is asserted that the difference is less
than the difference between an adult dogfish and an adult rabbit. It
would be perfectly true to say that the differences between the embryos
concern other organs more than do the diffe