sm with both historical and
scientific accuracy; and in this sense of the term Huxley was a
Darwinian; a convinced but free-thinking and broad-minded Darwinian,
who was far from persuaded that his tenet had a monopoly of truth, and
who delighted in shewing the distinctions between what seemed to him
probable and what was proved, and in absorbing from other doctrines
whatever he thought worthy to be absorbed. The present writer has
thought it so important to distinguish between these two sides of the
word _Darwinism_, that for the sake of clearness he has stated what he
believes to be the truth of Huxley's relation to Darwin before
beginning detailed exposition of it.

In consideration of Huxley's position before 1859, the most
interesting feature of his zooelogical work is the gradual preparation
that it was making in his mind for the doctrine of the _Origin_. He
was like an engineer boring a tunnel through a mountain, but ignorant
of how near he was to the pleasant valley on the other side; and,
above all, ignorant how rapidly he was being met by a much more mighty
excavation from the other side. To use what is perhaps a more exact
simile: he was like a child with half the pieces of a puzzle-map,
slowly linking them together as far as they would fit, and quite
ignorant that presently the remaining half would suddenly be given
him, and with almost no trouble would at once fit into the gaps he had
necessarily left, and transform a meaningless pattern into a perfect
and intelligible whole. Let us consider some of these map pieces. The
ultimate picture was the conception of the whole world of life, past
and present, as a single family tree growing up from the simplest
possible roots, and gradually spreading out first into the two main
branches of animals and plants, and then into the endless series of
complicated ramifications that make up living and extinct animals and
plants. Huxley was piecing together the scattered fragments, and
gradually learning to see here and there whole branches, as yet
separate at their lower ends, but in themselves shapely, and showing a
general resemblance to one another in the gradual progression from
simple to complex. The greatest of these branches that he had pieced
together was the group of Medusae and their allies, now known as
Coelenterates. He had formed similar branches for the Molluscs and
minor branches for the Salps and Ascidians, and, in his general
lectures on the whole animal k