“What has now been advanced will, perhaps, be deemed evidence sufficient to demonstrate,—­first, that the organs of these various families are traceable back to the same point in the way of development; or, secondly, when this cannot be done, that they are connected by natural gradations with organs which are so traceable; in which case, according to the principles advanced in 57, the various organs are homologous, and the families have a real affinity to one another and should form one group....  It appears, then, that these five families are by no means so distinct as has hitherto been supposed, but that they are members of one great group, organised upon one simple and uniform plan, and, even in their most complex and aberrant forms, reducible to the same type.  And I may add, finally, that on this theory it is by no means difficult to account for the remarkable forms presented by the Medusae in their young state.  The Medusae are the most perfect, the most individualised animals of the series, and it is only in accordance with what very generally obtains in the animal kingdom, if, in their early condition, they approximate towards the simplest forms of the group to which they belong.”

Such words, written before 1849, only differ from those that would have been written by a convinced evolutionist by a hair’s breadth.  But Huxley was not an evolutionist then:  it was Darwin’s work, containing a new exposition of evolution and the new principle of natural selection, that convinced him, not of natural selection but of evolution.  At Oxford, in 1860, it was for evolution, and not for natural selection, that he spoke; and throughout his life afterwards, as he expressed it, it was this “ancient doctrine of evolution, rehabilitated and placed upon a sound scientific foundation, since, and in consequence of, the publication of The Origin of Species,” that furnished him with the chief inspiration of his work.  The clear accuracy of his original judgment upon Darwin’s work has been abundantly justified by subsequent history.  Since 1859 the case for evolution has become stronger and stronger until it can no longer be regarded as one of two possible hypotheses in the field, but as the only view credible to those who have even a moderate acquaintance with the facts.  In 1894, thirty years after the famous meeting at Oxford, the British Association again met in that historic town.  The President, Lord Salisbury, a devout Churchman and with a notably critical intellect, declared of Darwin: 

“He has, as a matter of fact, disposed of the doctrine of the immutability of species....  Few now are found to doubt that animals separated by differences far exceeding those that distinguish what we know as species have yet descended from common ancestors.”

Huxley, in replying to the address, used the following words: