[[p. 103]] Mr. A. R. Wallace said that as M. Broca had expressed a difference of opinion with Professor Huxley, he should like to say how far he could support the views of the latter from his own personal observation. The Papuans had appeared to him to possess so many striking resemblances to the Negroes, of a mental as well as a physical character, that he had thought they must have some affinity to the Negro race. He had never, however, expressed his opinion upon this subject, because it was so entirely opposed to that generally entertained. As Professor Huxley had stated his views upon the subject, he wished to say that he agreed with him in relation to it. There could be very little doubt that the connection between the Papuans and the Negroes was closer than between the Papuans and the Australians. If this point could be proved, it would lead to some extraordinary conclusions with respect to the antiquity of man. He should be inclined to state his case much stronger than Professor Huxley had done. There were two modes of testing whether countries had formerly been joined together, and one was the similarity existing between the kinds of animals, and also of the depth of the sea between them. When these two points coexisted, the evidence was very striking that the two portions of land had been joined together. For instance, hardly a single animal was different in England from what it was in France. The sea also between them was not very deep. Hence we concluded that these two countries had once been joined together. Now there was just a similar kind of evidence existing here. The sea between New Guinea and Australia was shallow, not more than 100 fathoms in depth; the animals also were similar. On the other hand, between New Guinea and Africa there was the remotest possible affinity in their animal productions, [[p. 104]] while one of the deepest oceans rolled between them. It was therefore certain that the connection between Australia and New Guinea was comparatively recent, while that between Africa and New Guinea, if it ever existed, was exceedingly remote. Yet, strange to say, the men of New Guinea were more closely allied to the Africans than they were to the Australians. Now we could not account for this strange distribution of man by the theory of only one series of changes in the earth. There must have been a time not very remote when Australia and New Guinea were joined, so as to allow land animals to pass from one to the other. But if we suppose man to have spread from the one country to the other at that time, then the great differences that exist between the Australians and the Papuans must have been produced since, and we have no possible clue to the resemblance of such widely separated races as the Papuans and the Negroes. Their affinity, if it really is one, implies changes of physical geography vastly greater, and therefore vastly more ancient, than those which have determined the distribution of allied species of animals. It would imply (what there is other evidence to indicate) that the antiquity of the human race is comparable with that of the genera, rather than of the species, of other mammalia.