An arrangement of the recent and fossil collections in accordance with these most reasonable and philosophical views appears in all the versions of the plan until the last; now it has entirely disappeared, and the two collections are disposed in opposite wings of the building widely severed from each other. Owen had no special turn for organization, and he was probably in a minority of one against his colleagues on this point. Besides this, his fighting days were over, and he preferred peace to an ideal arrangement of which his contemporaries could not see the advantages.

Owen turned his enforced leisure at the British Museum to good account, and proceeded, with renewed activity, to occupy himself in various directions. In 1857 he gave lectures on paleontology at the Royal School of Mines, and his first course seems to have evoked the enthusiasm of his earlier days. Said Sir Roderick Murchison:

‘I never heard so thoroughly eloquent a lecture as that of yesterday.... It is the first time I have had the pleasure of seeing our British Cuvier in his true place, and not the less delighted to listen to his fervid and convincing defence of the principle laid down by his great precursor. Everyone was charmed, and he will have done more (as I felt convinced) to render our institution favourably known than by any other possible method’ (ii. 61).

Soon afterwards he was appointed (1859-61) Fullerian Professor of Physiology at the Royal Institution. Here again he chose ‘Fossil Mammals’ as his subject. In later years he gave frequent lectures on this and kindred subjects in the larger provincial towns. Nor must we omit the lectures to the Royal children at Buckingham Palace, which he delivered at the request of Prince Albert in 1860. These lectures, which were much appreciated by those for whom they were intended, laid the foundations of a close friendship between Owen and the Royal Family.

It must not, however, be supposed that these occupations diverted him from osteology. It was during this period that he wrote many of the paleontological memoirs to which we have already alluded. He continued to publish paper after paper on Dinornis as fresh material accumulated; and he composed, among others, his monograph on the Aye-Aye (1863), which perhaps excited as much attention as that on the Nautilus thirty years before.

Between 1866 and 1868 he published his elaborate treatise On the Anatomy of Vertebrates, obviously intended to be the standard work on the subject for all time. But alas for the fallacies of hope! It is an immense store-house of information, founded in the main upon his own observations and dissections; and from no similar work will advanced students derive so much assistance. But, unfortunately, no revision of his own papers was attempted; the novel classification employed has never been accepted by any school of zoologists; and the only result of the proposed division of the Mammalia into four sub-classes, according to their cerebral characteristics, was a controversy from which Owen emerged with his reputation for scientific accuracy seriously impaired, if not irretrievably ruined. He had stated, not merely in the work of which we are speaking, but in others—as, for instance, in the Rede Lecture delivered at Cambridge in 1859—that certain divisions of the human brain were absent in the apes. It was proved over and over again, in public and private, that this assertion was contrary to fact, and contrary to his own authorities; but he could never be persuaded to retract, or even to modify, his statements.

At the end of the third volume of the Anatomy are some ‘General Conclusions,’ which contain, so far as human intelligence can penetrate the meaning of Owen’s ‘dark speech,’ his final views on the origin of species. We have already shown that his mind was first turned to this momentous question during his visit to Paris in 1831, and that subsequently, during his work on the Physiological and Osteological Catalogues of the Museum of the College of Surgeons, it was continually in his thoughts. During this period he read, and was profoundly influenced by, Oken’s Lehrbuch der Naturphilosophie, a translation of which was published by the Ray Society, in 1847, at his instance. In his Archetype and Homologies of the Vertebrate Skeleton (1848) he says:

‘The subject of the following essay has occupied a portion of my attention from the period when, after having made a certain progress in comparative anatomy, the evidence of a greater conformity to type, especially in the bones of the head of the vertebrate animals, than the immortal Cuvier had been willing to admit, began to enforce a reconsideration of his conclusions, to which I had previously yielded implicit assent.’

Out of the study here indicated there grew a revision of the vertebrate skeleton, in which the homologues (i.e. the same organs in different animals, under every variety of form and function) were recognized, and a new system of osteological nomenclature was proposed. In this Owen did excellent work, which has been generally accepted. But in his anxiety to recognize and account for ‘the one in the many,’ he adopted Oken’s idea of the skeleton being resolvable into a succession of vertebræ, and evolved the idea of an archetype. It is almost inconceivable that the clear-headed and sagacious interpreter, whose sober conclusions we have indicated through a long series of zoological and paleontological memoirs, should have ever adopted these transcendental speculations. But there was evidently a metaphysical side to his mind, and he took a keen, almost a puerile, delight in this child of his fancy. He even had a seal engraved with a symbolical representation of it. To show that we are not exaggerating we will quote his own account of his views when sending the seal to his sister:

‘It represents the archetype, or primal pattern—what Plato would have called the “Divine Idea”—on which the osseous frame of all vertebrate animals has been constructed. The motto is “The One in the Manifold,” expressive of the unity of plan which may be traced through all the modifications of the pattern, by which it is adapted to the varied habits and modes of life of fishes, reptiles, birds, beasts, and human kind. Many have been the attempts to discover the vertebrate archetype, and it seems now generally felt that it has been found’ (i. 388).