The argument, that because there is an immense difference between a Man's intelligence and an Ape's, therefore, there must be an equally immense difference between their brains, appears to me to be about as well based as the reasoning by which one should endeavour to prove that, because there is a "great gulf" between a watch that keeps accurate time and another that will not go at all, there is therefore a great structural hiatus between the two watches. A hair in the balance-wheel, a little rust on a pinion, a bend in a tooth of the escapement, a something so slight that only the practised eye of the watchmaker can discover it, may be the source of all the difference. And believing, as I do, with Cuvier, that the possession of articulate speech is the grand distinctive character of man (whether it be absolutely peculiar to him or not), I find it very easy to comprehend, that some equally inconspicuous structural difference may have been the primary cause of the immeasurable and practically infinite divergence of the Human from the Simian Stirps. [32] It is so rare a pleasure for me to find Professor Owen's opinions in entire accordance with my own, that I cannot forbear from quoting a paragraph which appeared in his Essay "On the Characters, &c., of the Class Mammalia," in the "Journal of the Proceedings of the Linnean Society of London" for 1857, but is unaccountably omitted in the "Reade Lecture" delivered before the University of Cambridge two years later, which is otherwise nearly a reprint of the paper in question. Prof. Owen writes: "Not being able to appreciate or conceive of the distinction between the psychical phenomena of a Chimpanzee and of a Boschisman or of an Aztec, with arrested brain growth, as being of a nature so essential as to preclude a comparison between them, or as being other than a difference of degree, I cannot shut my eyes to the significance of that all-pervading similitude of structure--every tooth, every bone, strictly homologous--which makes the determination of the difference between _Homo_ and _Pithecus_ the anatomist's difficulty." Surely it is a little singular that the "anatomist," who finds it "difficult" to "determine the difference" between _Homo_ and _Pithecus_, should yet range them on anatomical grounds, in distinct sub-classes! [33] On the Affinities of the Brain of the Orang. Nat. Hist. Review, April, 1861. [34] On the Brain of a young Chimpanzee. Ibid., July, 1861. [35] On the Posterior lobes of the Cerebrum of the Quadrumana. Philosophical Transactions, 1862. [36] On the anatomical Relations of the Surfaces of the Tentorium to the Cerebrum and Cerebellum in Man and the lower Mammals. Proceedings of the Royal Society of Edinburgh, March, 1862. [37] On the Brain of Ateles. Proceedings of Zoological Society, 1861. III ON SOME FOSSIL REMAINS OF MAN.