The final result of the long discussion at Leyden was that, of twelve experts present, three held that the fossil remains belonged to a low race of man; three declared them to be those of a man-like ape of great size; the rest maintained that they belonged to an intermediate form, which directly connected primitive man with the anthropoid apes. This last view is the right one, and accords with the laws of logical inference. _Pithecanthropus erectus_ of Dubois is truly a Pliocene remainder of that famous group of highest Catarrhines which were the immediate pithecoid ancestors of man. He is, indeed, the long-searched-for 'missing link,' for which, in 1866, I myself had proposed the hypothetical genus Pithecanthropus, species Alalus. It must, however, be admitted that this opinion is still strongly combated by some distinguished authorities. At the Leyden Congress it was attacked by the illustrious pathologist Rudolf Virchow.[12] He, however, is one of the minority of leading men of science who set themselves to refute the theory of Evolution in every possible way. For thirty years he has defended the thesis: 'It is quite certain that man is not a descendant of apes.' He declares any intermediate form to be unimaginable save in a dream. [12] See Notes, p. 93. Virchow went to the Leyden Congress with the set purpose of disproving that the bones found by Dubois belonged to a creature which linked together apes and man. First, he maintained that the skull was that of an ape, while the thigh belonged to man. This insinuation was at once refuted by the expert palæontologists, who declared that without the slightest doubt the bones belonged to one and the same individual. Next, Virchow explained that certain exostoses or growths observable on the thigh proved its human nature, since only under careful treatment the patient could have healed the original injury. Thereupon Professor Marsh, the celebrated palæontologist, exhibited a number of thigh-bones of wild monkeys which showed similar exostoses and had healed without hospital treatment. As a last argument the Berlin pathologist declared that the deep constriction behind the upper margin of the orbits proved that the skull was that of an ape, as such never occurred in man. It so happened that a few weeks later Professor Nehring of Berlin demonstrated exactly the same formation on a human prehistoric skull received by him from Santos, in Brazil. Virchow was, in fact, just as unlucky in Leyden in his fight with our pliocene ancestor as he had been unfortunate in his opinion on the famous skulls of Neanderthal, Spy, La Naulette, etc., every one of which he explained as a pathological abnormality. It would be a very curious coincidence indeed if all these and other fossil human remains were those of idiots or otherwise abnormal individuals, provided they are old and low enough in their organization to be of phylogenetic value to the unbiassed zoologist.