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cinus Cebus fatuellus I know not.” Zoologists of " limited information" certainly thought that Linnæus named it Simia fatuellus,* and that the name Cebus fatuellus was given by Erxleben, in the year 1777, when the Swedish naturalist had long ceased to write, and only a year before his decease. It cannot be expected that even “a promiscuous audience” would be so credulous on a matter of elementary zoological fact as to believe that Linnæus gave generic value to the distinction between the Catarhine and Platyrhine monkeys. We must not, however, expect too much from an author who, before the Royal Institution, spoke of the Vervet monkey as Cercopithecus Lalandi, ignoring altogether the labours of the deceased zoologist and true labourer, Isidore Geoffroy St. Hilaire.f The illustrious Frenchman whose labours are thus slurred over has carefully pointed out the marks of distinction between the Cercopithecus Lalandi, Is. Geoff. (C. pusillus, Desmoulins), and the true Vervet, Cercopithecus pygerythrus, Desmarest; and when we see these two wholly distinct species confused together, we cannot but wonder in amazement what can possibly be the species of monkey to which such exceedingly vague reference is made.

The same writer, speaking of Schröder van der Kolk and Vrolik's Note sur l'Encephale de l'orang, confidently states, “ so far as the ventricles go, (sic in orig.) the figures given in the current number of the Natural History Review might very easily be interchanged with that standing for human structures in the drawing of anatomists, who had never dreamt of contrasting these organs with those of the ape. And should any one retaining any lurking kindness for the posterior cornu, come thus warped, to decide which of the two figures was intended for the simious, and which for the human brain, infallibly his judgment would be wrong.” We would ask any competent human anatomist to compare the anterior cornua of the orang and chimpanzee with those of man, and contrast the stunted, rounded, comparatively straight anterior horn of the ape's with its tapering, slender, divaricated homologue in man. No serious student, anxious only to arrive at a fair conclusion on the facts, and not by meretricious eloquence to enlist the sympathies of a “promiscuous audience,” will venture to assert that they can “ easily be interchanged.” The criticism applied to Apollonides, Tu certe neque tu vides intelligis, neque tu audes memoria tenes,” is most applicable in the present case. The mode in which the presence of a simial structure, admittedly

Systema Naturæ, ed. xii, vol. I, p. 43. Systema Regni Animalis, 8vo, p. 51. + D'Orbigny, Dict. Univ. d'Histoire Naturelle.

homologous with the hippocampus minor in man is paraded, with a view to obscure our perception of its developmental inferiority, is a characteristic example of the reasoning of the new transmutative school. No zoologist, however, of any repute, has denied the existence of these rudimentary structures.

It would be utterly inconclusive, and at an absurd variance with logical necessity, to assert, because a first-rate man-of-war, carrying a hundred and twenty or a hundred and thirty guns, exhibited one of the highest forms of naval power, that consequently smaller craft must be entirely destitute of any armament whatever. The forced application of the dictum of the schools de omni et nullo, is wholly inapplicable to the spirit of zoological classification, which is founded rather on our ideas of subordination to known type than any class characters.

The skeleton of the orang would have afforded in the indice" of the great toe, the same ground for impugning that zoological character of man which the brain of orang, in its indice du petit pied d'Hippo. campe" afforded in the denial of the “hippocampus minor" as a zoological character. A disingenuous advocate would have found the one just as serviceable for his purpose as the other. Viewed as discoveries, they are alike; but both closely resemble that of a certain nidamental structure, which gives, usually, but a short-lived pleasure to its finder.

In the above observations which it has been our duty to make on Professor Huxley's work, we have endeavoured while criticising his method of inquiry to recognize the fact that a derivative origin of the whole of the animate creation may be hereafter proved by accurate scientific induction. The day is long gone by when the probability of transmutation could be sneered down as the phantasm of a dreamer, or the product of the scepticism of an infidel. The possibility, nay, even the extreme likelihood of such a law being eventually established is now rapidly becoming a tolerated doctrine in the creed of deep thinking scientific men. Should such a theory be proved, it must be borne in mind that until it is so inductively demonstrated by observation, experiment, or well grounded inference, we are not entitled to assume its existence. If there is such a derivative law, and we have now the sanction of some of our highest zoologists to believe in its existence, when the time comes we shall not shrink from applying it to the discovery of the genesis of the human species. We have no real fear that the consequences which may result from the practical application of this law will be prejudicial to religion, morality, or society. It is the duty of scientific teachers to endeavour

VOL. I.-NO, I.

M

to discover this law; it is the duty of those who are sincere votaries of the truths of science to accept the law when it shall have been inductively proved. But, until the day comes when such a law shall be fully, entirely, and satisfactorily established, we must strenuously protest against the diffusion, even amongst “ the wider circle of the intelligent public,” of essays, the object of which is to render “ Man's place in Nature” closer to that of the brute creation. Professor Huxley's work is especially obnoxious to criticism, as it does not import a single new fact into the treasury of scientific knowledge; it contains no exalted views as regards man's true position, and the volume generally is destitute of that spirit which aims at the diffusion of accurate truths, ascertained by careful and patient investigation, and presented to the world in a temperate and ingenuous spirit.

We are now at the very threshold of the great controversy respect. ing man's true zoological position. To all those who may feel disposed to investigate the subject, and who may be inclined either to check free inquiry, or to rush hastily to a dogmatic conclusion, we would say, in the words of the philosopher of Königsberg, whose mental teachings have revolutionized the thoughts of mankind.

“Let each thinker pursue his own path; if he shews talent, if he gives evidence of profound thought, in one word, if he shows that he possesses the power of reasoning, reason is always the gainer. If you have recourse to other means, if you attempt to coerce reason, if you raise the cry of 'treason to humanity,' if you excite the feelings of the crowd, which can neither understand nor sympathize with such subtle speculations, you will only make yourselves ridiculous. For the question does not concern the advantage or disadvantage which we are expected to reap from such inquiries; the question is merely, how far reason can advance in the field of speculation apart from all kind of interest, and whether we may depend upon the exertions of speculative reason, or must renounce all reliance upon it. Instead of joining the combatants, it is your part to be a tranquil spectator of the struggle-a laborious struggle for the parties engaged, but attended in its progress, as well as in its result, with the most advantageous consequences for the interests of thought and knowledge."'*

Ανθρωπος. * Kritik der Vernunft.

163

MEDICAL PSYCHOLOGY.*

MR. Dunn is well known as one of our most industrious physiologists. A proof of this conclusion is to be found in the work before us, compiled during the frequent hasty leisures of an arduous professional life, and comprising some of the most florid expositions of the peculiar doctrines of the Idealist school of physiology. Mr. Dunn's generalizations to a great extent are connected with those of the phrenologist; we feel, however, that we should be doing him an injustice were we to classify them as phrenological. On the contrary, the influence of the school of Gratiolet is clearly manifest in some of Mr. Dunn's conclusions. The following is Mr. Dunn's classification of the various modes of nerve-action.

"Nervous actions are of a threefold character-physical, or excitomotory; sensory, or sensori-motor ; and volitional, or intelligent. But it is only in the highest class—the vertebrata, and where there exists a cerebro-spinal system that we recognize the existence and coordination of all these different kinds of nervous actions. In the very lowest animal organisms, the physical or excito-motory alone are present. These are essentially automatic, and occur without sensation ; to them, in the invertebrate kingdom, and as typical of animal life, the sensory or sensori-motor are superadded; whilst it is solely in the vertebrate series that the intelligent and purely voluntary come into play. Throughout the whole of the vertebrate subkingdom, the type of the nervous system, including man himself, is the same. It admits of a threefold division, in accordance with its functional endowments and co-ordinations—into,

"1. The physical or excito-motory and reflex—the true spinal system of the late Dr. Marshall Hall.

2. The nutritive and secretory, or ganglionic system, administering to the functions of animal life.

“The sentient, percipient, and intellectual, or the cerebro-spinal system.”

As regards the brain, the conclusions of Leuret and Foville are thus adopted by Mr. Dunn.

“Throughout the whole of the vertebrate subkingdom, the type of the brain is the same; and, on a general survey of the series, it cannot escape observation that the longitudinal convolutions, from their

Medical Psychology; comprising a brief Exposition of the leading Pheno. mena of the Mental States, and of the Nervous Apparatus through which they are manifested, with a view to the better understanding and Elucidation of the Mental Phenomena on the Symptoms of Disease. By Robert Dunn, F.R.C.S., England. 12mo. London, 1863.

first workings out, increase in number, volume, extension backwards, and in complexity of structure, as the animal rises in the scale of intelligence, and as the range of its perceptive activities widens. To unravel all the complexities of the intimate structure of the cerebral hemispheres has hitherto baffled the most eminent anatomists, with all the appliances that science can furnish; but Foville and Leuret have clearly shown that these hemispheres are chiefly made up of three distinct series of convolutions—the longitudinal, the commissural or anastomosing, and the transverse series. The longitudinal series are the first to be developed; and, according to Foville, they arise from a common central nucleus, the locus perforatus, and are closely banded together. It is indisputable that the internal convolutions are the primitive basement convolutions of the hemispheres, forming the broad lines of demarcation between the sensory and perceptive ganglia, between the sensational and perceptive apparatus; they are the central organs of the perceptive consciousness, and therefore the common portals to intellectual action and volitional power. Now, since these basement convolutions are the first developed, and as the whole series of longitudinal convolutions arising from the same central part are most intimately connected and associated with each other, and are commissurally banded together, my own mind rests in the conviction that an unifying bond of action pervades them, and that the entire series of longitudinal convolutions, as an aggregate or whole, constitutes the nervous apparatus of the perceptive consciousness-in other words, the instruments of all our immediate or intuitive cognitions ; not only the seat of the perceptive faculties, through the instrumentality of which, by the inlets of the special senses, we acquire a knowledge of external existences, their sensible qualities and physical attributes—of the differences and relations of things, their order or arrangement and numbers, and the phenomena of their action or events; but also of those purely ideational activities which form constituent elements in the composite nature of the personal or individual and social affections, and of the emotional, moral, and religious feelings of man.”

We would remark on this passage, that we presume the longitudinal convolutions are developed in the Australian races and the Andaman Islanders ; and we can only express our silent wonder how their “individual or social affections,” and “emotional, moral, and religious feelings,” are correlated with their brain development.

Mr. Dunn suggests what we believe to be a novel interpretation of the transverse convolutions of the brain.

“ After further observation and reflection, I have been led to an. other generalization, for the establishment or refutation of which I would appeal to the observations of the naturalist, as well as to the anatomical researches of the comparative anatomist. My own mind, at present, rests on the conviction that the vesicular matter of the transverse convolutions on the surface of the hemispheres furnishes the material conditions, the substratum, for the manifestation of the

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