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panzee as they do in the Baboon. In the Orang, however, though much reduced, they are still to be distinguished. Besides these matters, the temporal lobe becomes less horizontal and more depressed, as we proceed from Man to the Baboon.
These distinctions, with some others, have been pointed out in France by the late lamented M. Gratiolet,"* and in England by Professor Rolleston.1' Mr. Marshall, F.R.S., has also given his verdicti “ on the interesting question of the relative superiority of the Chimpanzee’s and Orang’s brain ” “in favour of the latter.”
Messrs. Schroeder, Van der Kolk and W. Vrolik, the dis— tinguished naturalists of Amsterdam, fully recognise the resemblance of the brain of the Orang to that of man to be closer than that presented by the brain of any other Ape.
The actual and absolute mass of the brain is, however, slightly greater in the Chimpanzee than in the Orang, as is the relative vertical extent of the middle part of the cerebrum, although, as before said, the frontal portion is higher in the Orang. When we turn to the Gorilla we find, from M. Gratiolet,§ that this much vaunted and belauded Ape is not only inferior to the Orang in cerebral development, but even to his smaller African congener—the Chimpanzee. ,
In the first place its brain scarcely equals (at least in some cases) that of the Chimpanzee in actual mass. It is also flatter, and its frontal lobe is less projecting in front of its temporal
. * “ Memoirs sur les plis cérébraux de l’homme et des primates.” 1' “Nat. Hist. Review,” vol. i. p. 201, and in a Lecture at the Royal
Institution, reported in the “Medical Times,” for February and March, 1862. ‘
lobe. Altogether, M. Gratiolet tells us, its brain-characters make of the Gorilla—in spite of its size and strength—the lowest and most degraded of all the latisternal apes. Moreover, the disposition of its convolutions is such as (in the opinion of M. Gratiolet) to connect it with the Baboons, while the Chimpanzee is similarly connected with the Macaques. Our author suggests that if the Orang be considered as the head and culminating point of development, following the line of the Semnopitheci and Gibbons, then the Chimpanzee may be taken to be the head, or, as it were, the Orang, of the series of Macaques, while the Gorilla is but' the culmination of that type of cerebral structure elsewhere exhibited by the relatively brutal and degraded Baboons. '
This is an appreciation of the animal widely different from that still popular in England, in‘spite of Professor Rolleston’s efforts to propagate the true Simian faith respecting this “ would-be king of the Simiadte.” '
The Professor expresses himself * as follows:
“ In the world of science, as in that of politics, France and England have occasionally differed as to their choice between rival candidates for royalty. . . . If either hereditary claims or personal merits affect at all the right of succession, beyond a question the Gorilla is but a pretender, and one or other of the two candidates the true prince. There is a graceful as well as an ungraceful way of withdrawing from a false position, and the British public will adopt the graceful course by accepting forthwith and hencefOrth the French candidate, and by endorsing M. Gratiolet’s proposal for speaking of the Gorilla as but a Baboon, of the Chimpanzee as a Macaque, and of the Orang as a Gibbon.”
There can be no question, then, but that in this most important organ, the Orang is man’s nearest ally, while the Gorilla is quite remarkably inferior.
This closeness of resemblance between the brains of the Orang and of man becomes yet more striking when we consider how great in this respect is the divergence between the Orang and those lowest of Apes—the Marmosets—in which the cerebrum is smooth and entirely devoid of furrows and con— volutions. In the lower sub-order—the Lemuroids—the divergence is much greater still, so much so, indeed, that the Half-Apes, as to their brains, have far nearer resemblances to animals altogether below the order PRIMATES, than to the higher members of that order. .
It must nevertheless be borne in mind, if we would estimate the value of these cerebral characters with perfect' fairness,
* “ Medical Times,” for February I862. v01. 1. No. cos. p. 184.
that forms zoologically distant sometimes resemble each other in brain-characters, while closely allied forms strangely differ. Thus, as M. Gratiolet has pointed out, the “bridging convolutions ” between the parietal and occipital lobes re-appear in the Spider Monkeys, while two species of Sapajou (Cebus), so closely allied as to have been sometimes treated as one species, differ strangely from each other in this respect.
Again, much stress has been laid, by some writers, on the great relative extension backwards of the hinder parts of the cerebrum and cerebellum in man. But in the little Squirrel Monkey of America the cerebrum extends backwards beyond the cerebellum, much more than it does in ourselves, while in that remarkable species of H ylobafes— the Siamang Gibbon (which is so man-like in its chin, and which exceeds man in the breadth 'of its sternum}—the cerebrum is so short as to leave the cerebellum very decidedly uncovered at its hinder part. In the Howling Monkeys, again, this exposure of the cerebellum is yet greater, and, nevertheless, these monkeys belong to a family in which, as we have seen, the overlapping of the cerebellum by the cerebrum attains its maximum of development.
Yet the psychical powers of different Apes are very similar. Not only the lowest Baboons of Africa (as 0.9. the famed “ Happy Jerry "‘ of Exeter Change) can be taught various and complex tricks and performances, but the less man-like American monkeys—the common Sapajous—are habitually selected by peripatetic Italians for the exhibition of the most clever and prolonged performances.
As to the two species of Sapajou, the brains of which are so different the one from the other, Professor Rolleston asks : “ Will anybody pretend that any difference can be detected in the psychical. phenomena, the mental manifestations of these creatures, at all in correspondence or concomitant variation with their differences of cerebral conformation?”
The difference between the brain of the Orang and that of Man, as far as yet ascertained, is a difference of absolute mass. It is a mere difierence of degree and not of kind.
Yet the difference between the mind of Man and the psychical faculties of the Orang is a difference of kind and not one of mere degreef" '
_ Thus on the one hand we see that we may have great differences in brain development unaccompanied by any corresponding psychical diversities, and on the other we may have vast psychical differences which it seems we must refer to other than cerebral causes.
* See “Quarterly Review,” July 1871.
Professor Huxley has sought to invalidate such inferencesf first by asserting, what is of course perfectly true, that intellectual power (as we daily experience it) depends not on the development of the brain alone, but also on that of -“ the organs of the senses and of the motor apparatuses.” But surely to this we may reply that in these respects no one pretends even that there is much difference between man and Apes.
' Secondly, Professor Huxley objects that the cerebral differences may be of so minute a character as to have escaped observation, and he compares the brains of Man and an Ape with two watches, one of which will, and the other will not, keep accurate time. He exclaims, “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.”
It would be, however, to say the least, somewhat singular to attribute to hypothetical and confessedly minute difl'erences effects which as yet we have not seen to accompany or be produced by certainly present and confessedly considerable differences which we have seen.
With how much force then does not the comparative anatomy of the present day re-echo the truth long ago proclaimed by Buffon,1' that material structure and physical forces can never alone account for the presence of mind.
Speaking of the Ape, the most Man-like as to brain, he says :—
“Il ne pense pas: y a-t-il une preuve plus évidente que la matiére seule, quoique parfaitement organisée, ne peut produire 'ni la pensée, ni 1a parole qui en est la signe, a moins qu’elle ne soit animée par un principe supérieur ? ”
In passing from the brain to the organs of sense, it may be remarked that the ear of the Gorilla is more human than that of any other Primate, in that it has a rudimentary lobule—that is to say, a rudiment of that soft depending portion into which the “ ear-ring ” is inserted.
The nose, on the contrary, exhibits a prominence slightly approximating to that of Man, not in the Gorilla but in one of the Gibbons, namely the Hoolock.
The projection of Man’s nose is, however, exceeded by that of a long-tailed Borpean Ape, called the' Proboscis Monkey on account of the length of its nasal organ. It belongs to the genus Semnopithecus. N 0 other species of that genus exhibits any approximation to a similar nasal elongation.