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lutely false to nature. It is true that the
fœtus of a mammal floats, during all its pro-
gress, in a watery fluid; and at the stage
we are here considering, its limbs are ill
matured, and a person of lively fancy (like
this author) might say that they resem-
bled' the fins of a fish; but they are not
made up of rays, nor have they the anato-
nical structure of fins; and the development
of the brain is, at this period, absolutely
different from that of a fish.
We have,
therefore, all the differences we want; and
we affirm that the fœtus of a man never
passes through the conditions of a fish; that
the development theory breaks down again,
(as it did at the two former steps of pro-
gress;) and that it will not bear the test of
exact anatomical analysis. It is, in fact,
from first to last, the mere fabrication of a
vague philosophy of resemblances.

5. All the higher animals are construct-
ed on one general plan; but as there are
differences in the perfect animals, by which
we separate them into classes, orders, ge-
nera, and species, so are there correspond-
ing differences in their fatal forms. In
every stage of progress the fetus is made
up of organic parts laid down, and of cer-
tain inseparable appendages.
The parts

ovum, (not accidentally, but by a physical | The fœtus of a mammal never breathes by necessity, arising out of the organic struc- help of gills, and is never in the condition tures just alluded to;) and become, after- of a fish. The author's assertion is absoward, more separated than they were before, from the higher classes. The animal framework is at this period considerably advanced; and in all the vertebrata (of whatever class) fissures begin to appear immediately behind the head, and descend into the interior of the intestinal tube. They have been called (we think unfortunately) branchial fissures; and this name has misled many authors who have taken up the philosophy of resemblances. These fissures gradually close up in all the higher classes, and with them they never are true branchial fissures. In fishes they are permanent, and on these fissures the gills are gradually formed, and nearly completed just as the fish quits the ovum; and a part of the same description applies to batrachians. Let these branchial fissures be taken from the embryo of a fish, a batrachian, and a mammal, and put before an anatomist, and he will tell instantly and certainly to which class each embryo must belong, for there is no confusion of structure. On the (so called) branchial fissures of a mammal's embryo, there is a simple membrane, with blood-vesels forming a kind of unbroken arch, without any the least trace of gills; but in frogs and fishes these fissures are covered with tufts and fringes, which are fed by lateral offsets laid down may be so ill defined that a fanof blood-vessels. There can be no mistake ciful person might call them, while in early in this structure; and in due course of na- progress, by some name suggested by his ture the embryo frog and fish (through the imagination; but he has no right to overfeeding of the lateral vessels) become fur- look the inseparable organic appendages, nished with the tufts and gills peculiar to which have all a reference to the perfection each class; and being so prepared, they of the animal form; are all prospective conpass out of the ovum into the water. Were trivances, and imply, by anatomical necesthe embryo of a mammal thrown off at that sity, the subsequent and more perfect contime into water (of its own temperature) ditions of existence. This remark is imit could not support life for a moment. portant. The great and prominent fœtal 4. Is, then, the embryo of a mammal ever differences have reference to future condito be called a fish? The philosophy of ex- tions; and do not arise merely out of the ternal resemblances might say yes; but the existing conditions of the organic parts laid philosophy of true anatomical differences down. Were the appendages defined only Our author cuts the matter short, by the existing conditions, different classes and tells us, (p. 196,) that in mammifers might be supposed, hypothetically, not only the gills exist and act at an early stage of to be laid down on one general plan, but to the fœtal state, but afterwards go back and pass into one another by insensible gradaappear no more; while in fishes the gills tions. Nature will not, however, do her are fully developed, and the lungs appear work on our hypotheses. She does her in the rudimentary form of air bladders.' This sentence is one mass of gross blunders. He mistakes the organic nature of the air bladder; and we again affirm that no one has ever seen a trace of gills on the (so called) branchial fissures of a mammal.

says no.

work on another plan. Let us then go further on the ascending scale--after fishes and frogs have left the ovum, and are no longer among the objects of immediate comparison. How are the higher classes brought to fœtal maturity? Is this done on

such a plan that we may suppose them to have sometimes interchanged their types, and to have passed one into another? We again reply in the negative; for we find not the semblance of any such organic interchange, while we attend to real anatomical differences. Is it possible, for example, that a bird's egg should be hatched into a mammal? We reply no-and the undeviating facts of nature bear us out; and, if we went no further, our reply would be grounded on a conviction like that of a clown, who believes that the sun will rise to-morrow. But the negative reply of an anatomist, or rather his positive reply, that a bird will be hatched from a bird's egg, is still better grounded. His confidence would be of the same nature with the conviction of an astronomer, that the sun must rise to-morrow; for he knows the anatomy of an egg, and he knows the organic cycles evolved within it, and evolved inevitably, by proper incubation. He knows that, from first to last there are organic contrivances within an egg which have a defined prospective reference to the laying down the organic structure of a bird, and apply not to that of any mammal; so that there is neither any obscurity nor any possibility of structural interchange. The ornithorhynchus is a mammal of a strange form, and of all mammals is nearest to a bird; but there are most wide organic intervals between them; and Professor Owen has shown us, that there is a defined mechanical difference in the anatomy of their ova, which proves (even before fœtal life has made a progress) that one ovum must be hatched outside the mother, and the other inside. We cannot dwell on mere details-we appeal only to leading facts and first principles. Going back, then, to the time when the lower vertebrates are quitting the ovum, we may in one sentence point out a broad set of fotal differences, implying, prospectively, a great organic separation in all the higher classes. At this period, when frogs and fishes are beginning to breathe by branchial tufts and gills, other amphibia and birds are breathing by allantoid; and never, for an instant, breathe by gills. At the same period of fetal development, hotblooded quadrupeds are breathing by allantoid and placenta jointly, while man is breathing by placenta alone. These are essential fœtal differences, connected with the last perfection of animal structure, and they form a wide anatomical separation so as to bar all interchange or confusion

of organic type.* These contrivances of nature are, we affirm, prospective, and not brought about by any natural or artificial change of physical conditions; and all the contrivances are wise and good, and well adapted to the future condition of the perfect being. This is the true law of nature, as told us by the successive forms of fœtal life. Were these facts known to our author? For his own sake we trust they were not known. At any rate, he has left his readers in perfect darkness as to the real evidence of the questions on which he presumes to write with no small confidence; and, so writing, he does his utmost to lead them into gross error and inextricable confusion.

If I ascend up into heaven thou art there; if I make my bed in hell, behold thou art there. My substance was not hid from thee when I was made in secret, and curiously wrought in the lowest parts of the earth. Thine eyes did see my substance yet being imperfect, and in thy book all my members were written, which in continuance were fashioned when as yet there was none of them. We quote not these words because of their authority. We bow to their authority; but we meet our author and his school on mere natural ground common to us all. We would fain, however, persuade our readers to pause a moment, and turn, as we have done, to the glorious-inspired song which links the material to the moral parts of nature, and teaches the true aim of high philosophy. It contains the very essence of ever-enduring truth; and the wisdom of man, whatever may be his skill among material things, may embrace it and feel its strength, but can never go one step beyond it.

into

6. After the well-known facts which we have now laid before our readers, we may further ask-' With what shadow of reason can any school of anatomists pretend to say, that one order of animals can pass another order, in the way of ordinary generation, seeing that the indispensable respiratory fœtal organs are so different in each? The fallacy which allows for a moment such an absurdity to pass, is this-that, to serve their purpose, they describe their fœtus by its central portions only, and not by its whole mass, including its organic appendages, which are essential to its continued life and its material structure.'t Look, say * Dr. Clark's Memoir on Fetal Develop

ment

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Dr. Clark, ibid.

they, (and so says our author, p. 206,) at | into two compartments by a septum, and the fetal heart of a mammal. It first re- that the swelling for the ventricles was dipresents a single tube, as in insects; next, vided at a later period of fœtal life. This an organ, with two communicating cavities, belief is, however, contrary to fact. The as in fishes; next, with three cavities, as septum is formed in the swelling correin amphibia; and lastly, it has four cavi- sponding to the ventricles, a considerable ties, as in birds. And so we are to con- time before it is formed in that correspondclude that a mammal's heart, after passing ing to the auricles. So that, for a period, through the lower types, is left at last in the heart of a human fœtus (as well as that the condition of a bird's heart, beyond of other mammals and of birds) has one auwhich it makes no advance. There is ricle and two ventricles. Hence it does not some positive truth, but there is far more pass through the form which is permanent positive falsehood, in these statements; and in the amphibia; but it does pass through a we are not satisfied with mere loose analo- form not found permanent in any known gies. All the vertebrate creatures, without creature. This grand correction of an old one exception, pass through their larva mistake we owe to the concurrent labors of state surrounded by water; and for the cir- Valentin, Rathké, and Bischoff, who stand culation of the blood, while the creature is in the first rank of discoverers; and no so surrounded with water, we learn from the good anatomist has pretended to contradict example of fishes, that a single heart is them. The hearts of birds and mammals do best. Now, the development of this organ not, therefore, pass through forms which are in the higher animals, while they remain in permanent in fishes and reptiles.'-(Dr. the womb, unites in it a capacity for two Clark.) To meet a possible objection we distinct, and apparently conflicting, modes may state, that we here speak of the norof action. Their blocd circulates by a sin- mal type of reptile-heart; for in the very hle heart like that of fishes, and their con- highest order of that class there is an apditions of life are perfect of their kind: but, proach to a double heart. Neither let it during these conditions, a double heart is be said that the heart of birds and mammals, laid down and perfected, in prospective when in the condition of a single tube, is wisdom, to meet a coming change when the identical with the corresponding condition creature is to pass into the air. 'Where of the heart of fishes; for in the former there is light there will be eyes,' says our case there are no aortic valves, while in the author. He tells us what is not true. He latter they are essential. speaks as if light made the eyes by some 6. The development of the brain in vernatural necessity; and not that the eyes tebrate creation, is like the development of were made in darkness, before light had the other parts. The fluid matter first ever reached them. Just in like man- laid down for it is potentially the whole ner, a child while in the womb wants not nervous system. Like processes begin the circulation of a double heart, and the upon things similar as to some of their rudiconditions of the things around it could mentary forms, but dissimilar in all their never imply that structure; but prospec- ultimate organic results; and, during the tive wisdom gives that structure in antici- early stages of fetal progress, differences pation of future want. The beauty of the appear which come soon so strongly into inechanism by which these double objects sight as to overwhelm the resemblances. are attained-partly by the structure of the No one can turn over the plates, detailing heart itself, and partly by the vessels which the development of the brain in two vertearise from it-have, in every age since Ilar-brates, from distant parts of the zoological vey's time, (except the present,) filled the mind with reverence and wonder.

scale, without being struck at once with the truth of our assertion,' Our author does But let us give our materialists a closer not appear to have studied a single standard meeting upon this question. The first rudi- work; yet there is a magnificent anatomiment of the heart appears as a single tube, cal literature connected with the fœtal and it gradually becomes bent like an Ital- questions; and he ought at least to have ian S; and it then makes three swellings leaned for support upon some high authoriwhich are afterwards, in mammals and ties. But he has contented himself with birds, to become the two auricles, the two quoting one or two superficial works of no ventricles, and the aorta, with the pulmo-authority whatsoever. One of his quotanary artery. This led to the belief that the tions is no better than a most ignorant swelling for the auricles was first divided misrepresentation of facts; for he tells us

then judge for himself: but he does no such thing. For, without giving his readers any notice of his artifice, he arranges the palæontological forms in accordance with his own hypothesis! This is not merely an intrepid use of the circular logic-it is an insult upon the reader; and an artifice we should be unable to describe in the conventional words of common courtesy. The whole pretended order is one mass of error. Fishes are in their wrong place-birds are put six steps above their proper geological

they may claim parentage with the human family. The scale, from first to last, is one mass of error; for geology, as we have shown above, bids defiance at every step to this writer's theory.

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(p. 206,) that ventricles and corpora striata are only found in mammals. We can tell him that they are found also in the lower classes. Again, with like inaccuracy, and on no better authority, he tells us (p. 235) in his grand creative scale, that the brain of the human fœtus, during its nine months' gestation, resembles that of the following nine orders-an insect, a fish, a turtle, a bird, a rodent, a ruminant, a wolf, a monkey, and a man. Let not the reader be imposed on by mere vague and ideal resemblances, which bear not the semblance of grade-monkeys are raised four steps, that sound anatomical truths. The brain, during fœtal progress, is like the other structures. It consists of parts laid down, and of parts in connected progress, which eventually complete the structure. Had, for example, a seven months' child the true 'Sex is fully ascertained to be a matter anatomical brain of a wolf, it must remain of development,' (p. 219.) In a proper ever afterwards through life of a beastly sense it is; but not in the sense in which nature. But it has, anatomically, a true our author uses the word development; for human brain, though not yet brought to what he adds is certainly not true. full size and proportion. What the moth-beings' (he tells us) are at one stage of the er's blood would do in the womb is done by embryotic progress female; a certain numthe mother's milk; and the little ill-formed ber of them are afterwards advanced to semblance of a child is gradually nourish- male.' If this fact be fully ascertained, ed in body, and brain, and every organ, till we might ask, by whom-by the author it reaches the full stature and perfection of himself? If so, we can only tell him, that humanity, being neither better nor worse the best authorities are all against him; and than the average of his fellow-creatures. that, in this instance, he seems to have gone Blunders and mistatements of this kind beyond them. Whether his apparent posimight have admitted of some semblance of tion arise from his having turned his back apology, and we might, perhaps, have refer- upon all our highest anatomical authorities, red our author's misconceptions on every or from his having outstripped them in the part of the Fatal Question, to a want of race, we must leave our readers to judge. knowledge, or to the delusions of a hypo-Soëmmering points out the different proporthetical spirit. But what apology can we make for the grand creative scale arranged in four paralel columns?-(P. 234.) We affirm, on principle, that no scale of nature, invented by man, can ever define the law and order of creation. But assuming auality in respect to sex is clearly made out. scale, let it be applied fairly, and therefore in subordination to the known facts of nature. Assuming the author's most fanciful and most false views of the fetal development of the human brain-do they derive support from the sequence of organic forms in the ascending series of rocks? He tells us, that, excepting a few mammals, the parity is perfect;' and 'that it is a wonderful evidence in favor of his hypothesis.' Does he, then, arrange the organic forms in the order of nature, and then put them in a column parallel to his hypothetical development of the foetal brain during the nine months of gestation? If he did this, he would act fairly, and the reader might

tions of the thorax, as well as of other parts of the male and female human embryo. Von Bäer, Valentin, Carus, and Rathké, all affirm that, from an early period, and afterwards through all the changes, the individ

In the first beginnings of life all distinctions are lost-at their first appearance the liver cannot be distinguished from the lung. But because the analysis of the ultimate elements of organic structure is impossible, it does not follow that they are all the same.'

(Dr. Clark.) It is evident that our author has not encumbered himself either with facts of structure or with anatomical authorities; but he has been led astray, as his manner is, by some vague analogies, which he has found in the works of Huber, and not perfectly comprehended. The facts stated by Huber (in his work on bees) are of great physiological interest; but they help not on, so much as one step, our author's

of this kind have been made, but they have all failed, and must ever fail, because they are contrary to nature's laws. There is, therefore, a grand unity in the works of nature proving a unity of creative will; but there is no confusion or mixture of species, when species are well ascertained: neither have the natural laws of atomic action in dead matter ever produced so much as one undoubted case, even of the lowest

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scheme of development; neither have they any bearing on his new sexual hypothesis; unless he can show that the sex of a lamb, a calf, or a foal depends upon a longer or shorter period of gestation. If his mind is troubled with any doubts upon this subject, (but it is not much its nature to let doubts stand in the way of theory,) we can only recommend him to shut Huber's book, which cannot help him, and to consult some honest British cattle-breeder, who condition of organic structure, endowed will tell him all about the matter. with life. All nature, then, at whatever There are strange facts in the metamor-point we meet her, and during whatever phoses of the lower, invertebrate animals; age in the past history of the earth, tells us, but all of them are governed by an undevi- with one unhesitating voice, that she has ating cycle of organic laws; and none of not enacted any law of spontaneous generthem gives so much as the shadow of an ation, and that she will not allow any powargument for the hypothesis of transmuta- er inferior to herself to mar her vestiges, tion from one species to another. As a or blot out her fixed organic types.* general rule, these changes (like the gradual changes in the fœtus of a mammal) are from a lower to a more perfect organic structure. But there are some striking exceptions, or apparent exceptions, to the rule. For example, the myriapods have, at first, three pairs of feet, and in that respect conform to the type of the higher insects; but afterwards the feet increase in number. So that we have here a creature of a lower grade passing during its early stages through the type which is permanent in the higher. Again, the larvæ of some creatures are locomotive, and have eyes; but, in the more fully developed state, when they reach the condition of perfect animals, they become fixed to one spot, and lose the sense of sight. Facts like these are of the deepest interest; but they make nothing for our general argument, and we must leave them. No vertebrate animal, after the first rudiments of its structure are laid down, conforms to the type of an invertebrate. In the beginnings of life, we find a general similitude; but the fundamental rudiments of organic structure are laid down upon an entirely separate plan. The whole animal existence of a vertebrate and invertebrate creature does, however, admit of a general com* We contend that many cases of ambiguous parison. In each case we have the ovum, the ova to have passed into a properly prepared generation are readily explained, by supposing the embryo, the larva, and the perfect animal infusion through the air. From some recent exwith the power of continuing its species. periments we learn, that when the air, which But by no contrivance or fostering can we has access to such an infusion, is made in the make a larva fruitful, or obtain from it a first instance to pass through sulphuric acid, no infusoria are produced, the floating ova having new animal of some lower type:-the at- been destroyed during their passage through the tempt must fail, because it involves a phy-acid. Connected with the subjects discussed in sical impossibili y. Neither can we, by any the preceding pages, we refer to an elaborate Reartifice of breed ng, push the perfect organ-University of Cambridge, read to the British Asport by Dr. Clark, Professor of Anatomy in the ic form of the c mplete animal beyond the sociation in 1834, and published in their third limitsof its species. Numberless attempts volume.

We have now done with the author of the Vestiges of Creation.' We have examined fairly, and on common natural ground, every material point of his argument. He fails from his first beginnings-he understands not the present condition of the Nebular Hypothesis-and, admitting the truth of the hypothesis, he has drawn from it the most unwarrantable conclusions. He understands not the present condition of Geology, and he has strangely, and to all appearance unfairly, distorted such facts as were before him, to serve the purposes of his hypothesis. He has not brought one allowed fact from actual nature to bear upon his theory. He seems not to have consulted one good authority on the Fatal Question; and he has, consequently, misconceived it, or misrepresented it at every turn of his professed argument. Men, like Von Bäer and Valentin, far from favoring the cry of some eager followers, (now feebly re-echoed in this country)— that the higher animals pass through stages of development, which are permanent in the lower-expressly tell us that such views are one-sided and insufficient. The

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