He made some
valuable contributions to Todd and Bowman's _Cyclopaedia of Anatomy_,
an elaborate publication now nearly forgotten and practically
superseded, but which was the standard anatomical work of the middle
of this century. He was unable to progress rapidly with his work upon
oceanic Medusae, as he was uncertain how to have it published; the
Admiralty refused to assist, and it was too lengthy for publication in
the volumes of the learned Societies. As a matter of fact, he did not
publish it until 1858, when it appeared as a separate memoir. To the
_Quarterly Journal of Microscopical Science_ and to the _Transactions
of the Royal and Linnaean Societies_ he contributed a large number of
memoirs dealing with the microscopic anatomy and relationships of
invertebrates, and, lastly, he gave a series of addresses at the Royal
Institution, which had been founded as a means by which leading men of
science might give accounts of their work to London society. Abstracts
of these lectures are published in the early volumes of the
_Proceedings of the Royal Institution_ and are interesting as shewing
the kinds of zooelogical subjects which were attracting the attention
of Huxley and which he considered of sufficient interest and
importance to bring to the notice of the general public. The first of
these lectures, and probably the first given in public by Huxley,
occurred on April 30, 1852, and was entitled "Animal Individuality."
The problem as to what is meant by an individual had been raised in
his mind by consideration of many of the forms of marine life,
notably compound structures like the Portuguese man-of-war, and
creatures like the salps, which form floating chains often many yards
in length. He explained that the word _individual_ covers at least
three quite different kinds of conceptions. There is, first, what he
described as arbitrary individuality, an individuality which is given
by the mind of the observer and does not actually exist in the thing
considered. Thus a landscape is in a sense an individual thing, but
only so far as it is a particular part of the surface of the earth,
isolated for the time in the mind of the person looking at it. If the
observer shift his position, the range of the landscape alters and
becomes something else. Next there are material, or practically
accidental individual things, such as crystals or pieces of stone;
and, lastly, there are living individuals which, as he pointed out,
were