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feet of a true rodent, and thus complete at two stages the passage from the aves to the mammalia ;" that, in fine, conditions being propitious enabled in some remote epoch an orang outang to procreate a human being; and that, thus setting aside with presumptuous pride and daring the Divine narrative which recounts that “God said, Let us make man in our image, after our likeness," we should rather attribute to the monkey tribe the origin of our race.* The author, when he has thus climbed to the top of the tree, seems to have some misgivings as to the climax he has attained ; and therefore endeavours to show that, although “the idea that any of the lower animals have been concerned in any way with the origin of man” might, when the circumstances were first presented to the mind, appear degrading, yet that, “knowing this fact familiarly and beyond contradiction, a healthy and natural mind finds no difficulty in regarding it complacently." This kind of argument reminds one of Voltaire's pithy comment upon the miraculous promenade of St. Denis after the trifling operation of losing his head, C'est le premier pas qui coute.

The work before us has attained a considerable part of its prestige, becanse it has been conceived by the reading public that, whatever may be thought of the theories it embodies, the author is deeply versed equally in the material details and in the general laws of science,-an impression, however, which is opposed by the concurrent testimony of those who are really versed in the great truths of astronomy, zoology, and physiology. Although it may be difficult, or rather impossible, to convey to the general reader the conviction of the utter fallacy of the outré doctrines propounded in these Vestiges, yet a few remarks will indicate in some degree the value of the groundwork upon which they rest. And, if we would apply the test of Voltaire, and seek to have the first step in the process elucidated, we might ask the author how an oviparous animal like the fish, which deposits its eggs, and can therefore exert no influence upon their further development, is enabled by its control over the embryo to “develop a reptile heart;" or, again, how an animal like a bird, wanting those special organs the mammary glands, without the agency of which we affirm that no new-born mammal can maintain an extra-uterine life, could nourish its assumed progeny; or, to adduce the author's own instance, how could the parent goose suckle the young rat. If the learned author had not quoted, by a somewhat ominous choice, the sacred bird of the capitol, we should have conjectured that he had in his thoughts the columbida, which, according to schoolboy authority,—and this in the present case we hold to be the most plausible authority,—do furnish pigeon's milk. As we have become entangled among the natatores and monotremata, we beg to suggest to the writer that, in his twentieth edition, it would be well to correct the error into which he has fallen in this the third, respecting the affinities of the ornithorhynchus, which, notwithstanding it has a bill like a duck and web feet like a goose, is more allied in its typical organization to the class reptilia than, as he avers, to that of aves.

Now, is it not a preposterous thing that a writer, who has ventured into the highest branches of philosophic anatomy and physiology, and who is hailed by the public judgment as a kind of incarnation of modern science in so many of its phases, should in the short space of seven lines † commit the egregious errors we have noticed, and which would expose him

* See the figures of Man and the Orang Outang.

+ See Vestiges, third edition, p. 224.

to the lash of any well-educated medical-student in this metropolis? It would be no answer to the objections we have urged, to contend that in the imaginary transition from species to species, the laws were different then to what they are now; nature, or rather nature's God, act by laws which know no change, and as we now are certain that the young of mammalia require to be suckled as a condition of their existence, so it must have been when they were first created.

But, to proceed, this theory of one species generating another is not only opposed to all experience—a thing in itself of great weight, but it is more especially incompatible with the mode of procedure by which it is clear nature is regulated in the matter of specific limitation. So far from one species being permitted to run into another, in obedience to the varying influence of external circumstances, which never perpetuates more than varieties, the most rigorous limits are set up, and the most efficient means are provided, to prevent any new form of animal life being perpetuated : we allude of course to the well-known fact that hybrids are infertile. The cause of this sterility has been investigated by Professor Waguer, and, in the case of birds, it seems to be connected with an absence or imperfect development of the spermatozoa. There are indeed some few instances of mules breeding; but the very exception proves the rule, for offspring is only produced when the pairing takes place with a perfect individual, and then the young return to the original fixed type. Similar results have been observed in the case of plants—the difficulties which are opposed to the reproduction of hybrids being so insuperable that, as M. de Candolle remarks, all such intermediate breeds tend incessantly to extinction. It thus appears that evidence of every kind is opposed to the author's hypothesis ; and in the face of the exact researches of such men as we have named, passages like the following, which are fair specimens of a large part of the argumentative portion of the work, will carry little or no weight :

“ Perhaps even the transition from species to species does still take place in some of the obscurer fields of creation, or under extraordinary casualties, though science professes to have no such facts on record."

And again :“ The lengthening of the legs of our common pig, when left to breed in the wilderness ; the change from the lean, bare dog of Turkey, to the short, thick, well-furred dog of Siberia ; the metamorphosis of the round, plump form of the Englishman, in a second generation, into the raw, wiry New Englander, are all transitions not less wonderful, in our age of comparatively (time-) uniform conditions, than was one of the passages between the cetacean and the pachyderm at a time when, probably, the part of the globe where the phenomenon took place was for the first time the scene of a physical fact of no less importance than the formation of rivers! These phenomena are of one character in their effects, the difference being only in degree.”

In this latter passage mere varieties are placed in the same category with species--nay, even with genera and orders; but we think, to say nothing of scientific objections, that the common sense of mankind will teach them there is something more than a “difference in degree” between the relationship of John Bull and his brother Jonathan, and that of a whale and a pig.

We believe that the writer of the Vestiges does not lay claim to any very great originality either in the way of discovery or of research ; however this may be, the theory of a successive perfectioning from the most simple to the most perfect species, in virtue of certain powers inherent in the animals themselves, has nothing of novelty in it, a similar speculation

in all its essential parts having been long since broached by the celebrated French naturalist, Lamarck. It was the idea of this otherwise admirable zoologist that in the beginning the most simple animal forms were created ; that these lower animals, possessed of certain plastic powers, and actuated by an internal sentiment or desire, were enabled to acquire, by the mere force of these desires or appetences, new and higher organs at will ; that a slug, for example, meeting with some obstacle or substance in its path, and having the wish to feel it, applied the fore-part of the head for that purpose, till, by such actions often repeated, a stimulus was excited, and at length two or four tentacles or horns were produced. This seems absurd enough ; but Lamarck's account of the development of the respiratory organs is even more palpably opposed to the certain evidences of comparative and developmental anatomy. He says that this system commences by the breathing tubes possessed by insects and other articulate animals, and which are called trachee; that these became changed into branchiæ or gills; and that at last the branchiæ themselves were definitely converted into lungs. Now this is all pure speculation ; but, at the time when it was first announced, it captivated many shallow people, because it seemed to be in accordance with ascertained facts. Fortunately, a wiser spirit has since been infused into these pursuits, and the more accurate knowledge thus acquired has swept away the fine-spun theories of Lamarck, by showing, among other things, that this conversion of gills into lungs cannot possibly be true, inasmuch as all vertebrate animals, whatever may be the organ by which they ultimately respire, possess at the same time, in the embryotic condition, though usually in a rudimentary condition, branchiæ and lungs, a combination which is temporarily seen in the common tadpole, and permanently in the perenni-branchiate amphibia, such as the proteus, the siren, and the axolotl..

Noting the similarity between these fantastic hypotheses of Lamarck and the equally absurd ones of our author, we were rather curious to see how the latter would regard these kindred researches. They are thus handled :

“Now it is possible that wants and the exercise of faculties have entered in some manner into the production of the phenomena which we have been considering ; but certainly not in the way suggested by Lamarck, whose whole notion is obviously inadequate to account for the rise of the organic kingdoms. Had the laws of organic development been known in his time, his theory might have been of a more imposing kind.”

It argues little we think for the writer's acquaintance with the intricacies of developmental anatomy that he should thus have appealed to its laws as confirming the notions of Lamarck, whilst, as we have shown, it is precisely by these very laws that the whole system has been overturned. A careful perusal of these Vestiges has shown us the cause of these and similar palpable mistakes; for it is continually made apparent that the writer, although he has picked up from reviews and elementary text-books many of the isolated facts of developmental anatomy, has not grasped the laws of which they are but the outward and visible signs. It would be altogether incompatible with our limits to quote the many instances which support this position -one only must in this place suffice. It is asserted, p. 196, that in mammals “ the gills exist and act at an early stage of the fætal state, but afterwards go back and appear no more.” In this very short passage there are several errors; first, it is not true that gills exist exist at any period in mammals and birds—there is merely a tracing out of the branchial apparatus by the formation of branchial fissures, arches, and blood-vessels; second, it is not true that the gills are ever active in mammals or birds, and the assertion to the contrary argues a complete ignorance of the laws in obedience to which these transient forms are assumed; third, the gills, or, to use more correct language, their typical representatives, “ do not go back and appear no more” in mammifers, but, on the contrary, go forward and appear-albeit, in new forms, with which it is clear the writer has no acquaintance, though the metamorphoses herein implicated are among some of the most interesting phenomena of that which forms a staple commodity in the Vestiges organic development.

Our readers will perhaps bear with us whilst we briefly trace the transformations of the upper branchial formation, which in the above quotation is erroneously stated to disappear. The fissure, which is comparable to one of the gill-apertures seen in the common skate, lamprey, and shark, and which at first leads completely through from the skin of the neck into the back of the mouth or throat, subsequently in birds and mammals, becomes divided by the deposit of a plastic substance into an outer fissure opening on the skin, and an inner fissure opening into the throat. By the continuation of the metamorphosis, the outer fissure becomes converted into the external tube of the ear, and the inner fissure into the tympanum and passage called Eustachian leading from it into the throat, whilst the plastic matter above noticed is transformed into the membrani tympani. A similar but more limited transformation occurs in reptiles, among which the batrachia are most interesting. The account above given shows, that as the tympanum is formed from the branchial apparatus, no animal can possess that part of the ear and the gills at the same time: hence no fish has a tympanum, nor does the tadpole, which is so closely allied to the class of pisces, possess that part; though it is acquired in the process of metamorphosis, and distinctly appears in the frog. The same law applies to the perenni-branchiate amphibia, some of which do retain, as the name implies, the gills throughout life, such as the siren and axolotl, and consequently have no tympanum, whilst others lose the branchiæ and acquire the drum of the ear.

The author is not more happy in his comparative anatomy than in his attempt, to detect the secret of the zoological series. Thus, in speaking of the struthionidæ or birds of the ostrich family, he states they possess a diaphragm (the great muscle of respiration), which is wanting in other birds. All we can say is, if he will condescend to walk into Leadenhall Market, and buy a rook, he will find upon dissection a very well-developed diaphragm. After such a slip as this, it is not surprising, that he adopts, for the purpose of supporting the utterly untenable position that in the geological formations the simpler orders only of each class are met with in the earlier strata, the prevailing error that the cartilaginous fishes are inferior to the osseous fishes. We hold, on the contrary, that by appealing to that which in truth is the animal, and which must ever determine the precise position of each class, the nervous system namely, it will be seen that, although in the myxinoid and cyclostomatous divisions the brain is very simple, yet that in the highest orders, the rays and sharks, the encephalon mounts upwards in organization above that of any osseous fish. In keeping with this high development of the central organs of animal life, it is seen that the heterocercal form of tail prevails, an evident and recognised approach to the next class above, namely reptiles; in fact, in the skate there is no longer the tail of the fish, but of the newt or lizard. We say nothing of the ovo-viviparous form of generation displayed by many chondropterygians, although it is a

point in the inquiry, because it is one of the functions of the vegetative life, which is most liable to mislead, if it be assumed as a guide in determining the relative elevation of the animate tribes.

Having exhausted our space, we must here pause. In our next number we propose to conclude our notice of the Vestiges, by considering what is evidently regarded by the author as his stronghold—organic development.



We have all read or heard of Rip Van Winkle ; how that he went forth one summer eve into the deep woods, and there slept ; how that on waking he found his slumber had lasted a century; and how that, on wandering back to his old haunts, he found a new generation, which remembered him not. We have all heard or read of this; and perhaps, in the fulness of our self-satisfied wisdom, we have laughed at it as a poor, foolish story, and have turned, after some inward chiding of ourselves for so wasting our time, to what we were pleased to term weightier matter, better worth our deep attention. But if we have so judged this poor story, it seems to me, my friends, that we have somewhat erred. The shallowness was in our brain that we could not discern the deep moral of the tale,-a moral which, rightly considered, may lead us on to think upon that which shall be of service to us and ours.

Rip Van Winkle slept, but God, and nature, our great mother, did in no wise sleep. They two, the one subservient to the other, toiled on without cessation, fainting not, nor wearing in their good work. The tide of life ebbed and flowed in its accustomed channel ; babes grew and prospered, quitting their mother's arms and struggling into manhood; men waxed old and feeble, and gave place to others; and God's word came down upon the earth, and returned not to him again without accomplishing its end. And those great externals which surround us—which we term inanimate, these slept not. The heavens dropping fatness, the stars in their ceaseless courses, the earth teeming with good things, the ambitious brook struggling in its narrow bed to make itself a river, and the great sea itself,—these slept not, nor loitered, but did the work allotted to them, plainly pointing out to man that his mission here is toil—toil that he may win by the sweat of his brow the inheritance so long forfeited.

Rip Van Winkle slept and was not changed; but the busy world around, which had toiled on through that long century, had changed in much, so that he knew it not. The dank, thick brake, fit only for the lurking place of beasts, near which he had lain him down to sleep, had given place to the broad strong oak, fit for the use of man ; the little flower, which his weary head on lying down had well nigh crushed, had done its part a thousand times in the work of reproduction-blooming to its full extent, withering on its taper stem, falling on the bosom of its mother-earth, and fertilizing the ground with its decaying leaves; the forest, once pathless, had become a ploughed field; the brook, which babbled uselessly of old, had

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