Neto WLoxke. HE GREEK TESTAMENT : with a critically Revised Text : a Digest of Varicms Readings : Marginal Refer- ences to Verbal and Idiomatic Usage : Prolegomena : and a Critical and Exegetical Commentary. For the use of Theological Students and Ministers. 2 vols. 8vo. By Henry Alford, M.A., Vicar of "Wymeswold, Leicestershire, and late Fellow of Trinity College, Cambridge. Vol. I., price £1 4s., containing the Four Gospels, now ready. Vol. II. preparing. A TREATISE ON MORAL EVIDENCE, illus- trated by numerous Examples both of General Principles and of Specific Actions. By Edavard Arthur Smedley, M.A., late Chaplain of Trinity 'College, Cambridge. 8vo. Is. 6d. in. THE APOLOGY OF TERTULLIAN, with English Notes and a Preface, intended as an Introduction to the Study of Patristical and Ecclesiastical Latinity. By H. A. Woodham, LL.D., late Fellow of Jesus College, Cambridge. 8vo. 8s. 6d. Second Edition. IV. AN ANALYSIS OF PALMER'S ORIGINES LI- TURGIC^E ; or, Antiquities of the English Ritual ; and of his DISSERTATION on PRIMITIVE LITURGIES : for the Use of Students at the Universities, and Candidates for Holy Orders, who have read the original Work. By W. Beal, LL.D., F.S.A., Vicar of Brooke, Norfolk. 12mo. 3s. 6d. FOUR SERMONS Preached before the University of Cambridge, in November 1849. By the Rev. J. J. Blunt, B.D., Margaret Professor of Divinity. 1. The Church of England— its Communion of Saints. 2. The Church of England— its Title and Descent. 3. The Church of England— its Text — the Bible. 4. The Church of England— its Commentary— the Prayer- Book. 5s. By the same Author. FIVE SERMONS Preached before the University of Cambridge. The first four in November 1845 ; the fifth on the General Fast Day, Wednesday, March 24, 1847. 8vo. 5s. Gd. CAMBRIDGE :— J. DEIGIITON. /. / /* THE LIBRARY OF THE UNIVERSITY OF CALIFORNIA PRESENTED BY PROF. CHARLES A. KOFOID AND MRS. PRUDENCE W. KOFOID Digitized by the Internet Archive in,2007 with funding from Microsoft Corporation http://www.archive.org/details/discourseonstudiOOsedgrich DISCOURSE ON THE STUDIES OE THE UNIVERSITY OF CAMBRIDGE. BY ADAM SEDGWICK, M.A., F.R.S., WOODWARDIAN PROFESSOR, AND FELLOW OF TRINITY COLLEGE. THE FIFTH EDITION, WITH ADDITIONS, ANT> A PRELIMINARY DISSERTATION. LONDON : JOHN W. PARKER. CAMBRIDGE : JOHN DEIGHTON. M.DCCC.L. IPrlnteU at tfie ©ntttersltp $ress. l'?SO TO THE MASTER, FELLOWS AND STUDENTS OF TRINITY COLLEGE, CAMBRIDGE, AND ESPECIALLY TO THOSE AT WHOSE REQUEST IT IS PUBLISHED, THE FOLLOWING DISCOURSE IS DEDICATED BY THEIR AFFECTIONATE AND FAITHFUL SERVANT, THE AUTHOR. CONTENTS. Preface to the First Edition. Preface to the Fifth Edition, PRELIMINARY DISSERTATION. SECT. PAOB 1 Introductory Remarks on the Doctrine of Final Causes . ix 2 Theory of Spontaneous Generation, Transmutation of Spe- cies, &c xvii 3 Fcetal Transformations, and their bearing on the Theory of Development xxvii 4 Organic Phenomena of Geology, and general remarks on their bearing on the Theory of Development . . . xliv 5 Animal and vegetable Remains of the Primary or Palaeozoic Division lviii First Forms of Vegetable and Animal Life as described in The Vestiges, &c lxxviii 6 Fossils of the Secondary Division, &c lxxxix 7 Organic Remains of the Tertiary Division, &c. . . . cvii 8 Materialism. Mechanical and Moral Laws. Laws of Chance. Tendencies of Modern Science. Fantastical views of Nature. Evils of rash Generalization. Educa- tion, &c. . . . cxl 9 Conditions of the Mind that have led men to deny a Per- sonal Creator. Atheism and Pantheism. Illustrations of the doctrine of Final Causes. Galvanic and Phrenological Hypotheses, Mechanical Inventions, &c. . . . clxxiii 10 On the Ideal Theory of Locke — imperfections of his Analysis. Schools of the Idealist and the Sensualists. Mischief of setting up Idealism as the interpreter of material nature, illustrated by the works of Oken, &c. cxcii M314134 VI CONTENTS. SKCT. PAGE 11 Digression on some Discoveries of Oken followed out by Owen. Archetype of Nature. General Scale of Nature. Never existed at one time in the History of the Earth. The reconstruction of the Scale subversive of the Theory of Development, &c ccvi 12 Reconsideration of the Argument for Final Causes. Mi- racles. Belief in a First Cause, and Moral Conclusions from it. Induction the Fountain of all Material Truth, &c. ccxxix PART II. 1 Pantheistic views of Revelation and its Evidences, and Comments on the Newtonian Philosophy. Evidences of Christianity, Historical and Prophetical. Moral Purity of the Gospel. Its Propagation and effects on the Pro- gress of Man, &c cclvi Arguments from Analogy ccciv 2 Recent Changes in the University Course. Modern Science of Cambridge — Philosophical Society. Modern external improvements. Moral and social character of the Stu- dents, &c cccxxiii External Improvements in Cambridge .... cccxliii 3 Modern religious movements. Principles of the Church of England contrasted with those of the Church of Rome. Tracts for the Times, Terms of Communion. Immo- rality of the Tracts. Acts of Apostasy. Causes of error in our estimate of religious and moral questions. True Catholicity. Conclusion ccclxvi DISCOURSE, (pp. 1-94). APPENDIX TO THE DISCOURSE. NOTE PAGK A Examples of the Method of Induction 95 B General Diffusion of the Imponderable Agents through Space . 102 C Reply to Fanatical Objections against the Study of Physical Science 104 D On the Nebular Hypothesis 118 E Religious Bearing of the Study of Nature — La Place's Senti- ments on Education — Natural and Revealed Religion — Fana- tical Objections to some passages lh the Discourse . .127 F Natural Theology — Paley — Examples of Adaptation in Com- parative Anatomy, derived from the Teeth and Jaws of Mam- mals 143 G Heathen Views of Final Causes. Reasons which have led Men to reject the Truth of Natural Theology . . . .150 H Objections to some passages in Paley's Moral Philosophy . 160 SUPPLEMENT TO THE APPENDIX. No. I. Additional Remarks on the Nebular Hypothesis . . . 176 II. Animal Creations by Galvanism 183 III. On the Placoid and GanoYd Fishes in the Palaeozoic Strata, and their places in the Organic Scale 185 IV. On the supposed Interchange of Vegetable Species — Hybridi- zation—Alternate Generations of Steenstrup — Parthenogene- sis of Owen, &c 193 V. On the Development of the Animal and Vegetable Kingdoms in the oldest known Fossiliferous Strata .... 207 VI. On the supposed derivation of the Terrestrial Flora from the Marine, by a Natural Transmutation of Species . . . 212 VII. On the Use and Abuse of the word Law ; and on the methods by which we rise to a right conception of it among physical Phenomena — Kepler's Laws — Bode's Law — Kirkwood's Law, &c. ib. VIII. A Series of Extracts from Oken's Physiophilosophy . . 222 IX. Remarks on the Theory of The Vestiges, and on the Author's Explanations — Moral and Religious considerations opposed to Materialism 247 X. Transactions of the Cambridge Philosophical Society — The Prelude of W. Wordsworth, &c 314 ERRATA. Preface, p. xviii. 1. 21, for in which read from which xxxvii. 1. 20, for a back-bone read a back -bone and spinal chord lxiv. 1. 12, for a Cestracion read a Cestraciont lxxxii. second Note, for p. 64 read p. 65. xcii. 1. 28, for Brachiopoda read Cephalopoda clx. Add the following foot-note, See Supplement to the Appendix, No. IX. ccxv. 1. 7i for the Radiata read those Radiata cccxii. 1. 8, for evidences our read evidences of our ccclxvi. 1. 15, for Churchman Low read Churchman and Low ccccx. 1. 22, for self-love breed read self-love and breed ccccxv. 1. 6 from the bottom, for It read it lb. last line, for (we dare to say logically) read (we dare to say) logically Appendix, p. 122, 1. 9, for round our own read round their own Supplement to Appendix, p. 178, 1. 16, for infra p. 27 read supra p. 27- PREFACE TO THE FIRST EDITION. The substance of the following Discourse was delivered in the Chapel of Trinity College, on the day of the Annual Commemoration in December last, and is published at the request of the junior Members of the Society, to whom it was more immediately addressed. As the long delay in its publication requires some apology, the Author begs leave to state, that the request, on which he is now acting, first reached him during the Christmas vacation, when he was absent from the University ; and that for some weeks after his return he was so much occupied in completing a course of lectures and in passing two memoirs through the press, that the Lent Term had nearly expired before he had time to revise his MS. for the printer. With- out any further delay it was then struck off as far as page 33 ; and he hoped to have published it at the commencement of the Easter Term. During its progress through the press he found however that he had undertaken a more difficult task than he had imagined : for having animad- verted with much freedom on some parts of the X PREFACE TO THE FIRST EDITION. Cambridge course of reading, he felt himself com- pelled, before he dared to give what he had written to the public, to enter at more length on a justifica- tion of his opinions. On this account, his remarks on the classical, metaphysical, and moral studies of the University (extending from p. 33 to p. 91) were cast over again, and expanded to at least three times their original length. Before this part of his task was completed, an attack of indisposition compelled him for a short time to quit the University ; and on his return the languor of ill health, and a series of engage- ments of which it is not necessary here to speak, prevented him from immediately resuming it : so that the latter part of this Discourse was not printed till a late period in the Easter Term, when most of the junior Members had left the University for the long vacation. On this account he re- solved not to publish before the University reas- sembled in the October Term. Lest he should be accused of printing a dis- course too widely differing from the one he was requested to publish, he wishes to state, that (with the exception of mere verbal corrections) it is, as far as p. 33, in the form in which it was first written, and that the conclusion has undergone no change : and in the two parts which have been so much expanded, he has preserved the scope PREFACE TO THE FIRST EDITION. XI and sentiments, and in many instances the very words, of his first sketch. The notes added in an Appendix are not written to serve any purpose of ostentation. By most academic persons they may be considered unnecessary : but should a single reader find them of use in explaining or enforcing what is stated in the text, the Author will not regret that he has written them. He has attacked the utilitarian theory of morals, not merely because he thinks it founded on false reasoning, but because he also believes that it pro- duces a degrading effect on the temper and con- duct of those who adopt it. It is, however, more easy to pull down than to build up ; and he thinks it unfortunate that there is no English work on morals at once unexceptionable in its principles, and cast in such a form as to meet the wants of the University. Bishop Butler's three Sermons on Human Nature and his Dissertation on the Nature of Virtue have lately become subjects of examina- tion in Trinity College. Of their kind, they are works of inestimable value : but they are devoted rather to the discussion of the principles of morality than to the establishment of a system of moral phi- losophy ; and they are considered by most persons, who begin to speculate on such questions, both diffi- cult and uninviting. Before concluding this Preface, the Author dis- Xll PREFACE TO THE FIRST EDITION. claims any notion of holding out the following pages as a formal dissertation on academic studies. Such an attempt would be far above his powers ; not falling in with his usual habits of thought, and requiring research for which he has neither time nor inclination. What is here printed treats of subjects treated of a hundred times before, and pro- fesses no originality, except what it derives from the circumstances under which it was delivered and the persons to whom it was addressed. Should it be the means of leading even a small number of them to think more justly on any of the subjects of academic learning, and to combine moral and religious habits of thought with those severe physical studies, during which the best faculties of the mind are sometimes permitted to droop and wither, his most earnest wishes will be accomplished. Trinity College, Cambridge, Nov. 5, 18.33. PREFACE TO THE FIFTH EDITION. § 1 . Introductory Remarlcs on the Doctrine of Final This Edition, with the exception of a few verbal corrections too insignificant to require any formal notice, is a reprint from the text of a Discourse — first pub- lished in 1833. Several additions have, however, been made to the Notes of the Appendix, and their arrange- ment has been changed. Note (D) on the Nebular Hypothesis*, and note (E) in reply to some objections which had been taken to the religious principles of the Discourse, are entirely new. In note (G) I have added a translation of the Greek extract from Xenophon's Memorabilia : and about two pages have been added to note (H) (note (E) of the former editions), on Paley's Principles of Moral and Political Philosophy. I do not wish to change one sentence of what I had written on the Utilitarian Theory of Morals ; because my opinions on that subject are unchanged, and I think it not expe- dient to write upon it at greater length. As the Discourse and the Notes of the Appendix were written at different times, after long interruptions, and to meet specific objections, I have been led into * See the Supplement to the Appendix No. I. S. D. b ) X PREFACE TO THE FIFTH EDITION. several repetitions which might be avoided in a more formal treatise : but the very repetitions are not per- haps without their use. During the passage of this edition through the press, I intended, in a concluding note, to discuss some points just touched on in the body of this little work ; and, especially, to notice at considerable length the development of organic forms in the successive strata of the earth. I, however, soon discovered that the subject was far too large for a single note : and had there been no other reason for leaving this part of my task incomplete, the interrup- tions of ill health would have prevented me from giving more than the bare outline of an argument which I hope to fill up at some future time. The outline, such as it is, I have thought it best to subjoin in this Pre- face ; requesting the reader to consider it not so much an attempt at a full and formal argument, as a series of suggestions, which may be, perhaps, hereafter more expanded and better enforced. (1) The kingdoms of nature are presented to our senses in a succession of material actions, so adapted to one another as to end in harmony and order. All these changes and movements among the things around us seem to be produced by powers of nature we call second causes: but the mind of man cannot and will not rest content with second causes, and is constrained to look above them to some First Cause. Among the things produced by the hands of man we are able to separate works of accident from works of design : we gain this knowledge by experience, and by reflecting on PREFACE TO THE FIFTH EDITION. XI what passes within ourselves : and it is by taking this knowledge with us in our judgments on the works of God, that we are naturally led to a conception of an in- telligent First Cause, capable of producing all the phe- nomena of the visible world. On the other hand, it is said by Geoffroy Saint- Hilaire, and other materialists of the same school, " We ascribe no intention to God, for we do not trust the feeble powers of reason "..."we observe facts, and pre- tend only to the character of historians"..." we cannot make an intelligent being of nature/' &c. &c. There is a latent sophism in all such statements as these ; and were the authors of them true to their own principles, they ought to stop short among individual phenomena, and never ascend to the conception of any general law of nature. While they deny the indications of a God, they deify dead matter, by deriving from it works that have all the external characters of things produced by design and high intelligence. We are constrained, by the very law of our common being, to ascend to the conception of some power ordaining and directing the natural movements and changes we see around us. Among these changes we see the most obvious marks of intelli- gence. How are these indications to be accounted for ? We cannot deify dead matter, and make of it an intel- ligent cause. We are, therefore, constrained to speak of an intelligent power superior to nature ; because we cannot, without the assumed existence of such a power, so comprehend the works of nature as to bring them b2 Xll PREFACE TO THE FIFTH EDITION. into co-ordination with the knowledge we have of our- selves, and our experience of the things around us. (2) The doctrine of Final Causes, drawn from the structure of the organic world, has perhaps been stated at sufficient length in the following Discourse, and the Notes of the Appendix. It cannot be better stated than in the homely and graphic argument of Socrates {infra p. 151): The eye is made to see, the ear is made to hear, and the organs of every living being, so far as we can comprehend them, have a design and purpose. Under this point of view " these various organs seem altogether the contrivance of some wise artificer who loves the beings he has created," {infra p. 152). Or- ganic structures give us, therefore, a clear proof of the doctrine of Final Causes ; and these causes have not, according to one of the quaint conceits of Bacon, been unfruitful, like virgins dedicated to God; but in the hands of Cuvier, Owen, and many other great physiolo- gists, have not only rationalized a multitude of known truths, but have also been continually pregnant with new discoveries. The same school of materialists, to whom 1 have already pointed, object to our language as well as to our principles. It is true that in all cases we are com- pelled to express our meaning in words which are but the reflexion of our own nature. We know what we mean by our own muscular force, and we apply the same word force, it may be figuratively, to the powers of nature producing mechanical movement. So also we comprehend the meaning of cause and effect, will and PREFACE TO THE FIFTH EDITION. Xlll design, as applied to the works of our own hands : and in like manner we analogically apply these words to organic structures and anatomical designs proceeding from the workmanship of God. But should we gain by any change of the language whereby we describe the phenomena of the organic world as reflected in the mind of man ? While speaking of organic bodies shall we only tell, like the modern materialist school, " of the principle of connexion" — " the elective affinities of organic elements" — "the equilibration of organs,'" — &c, and think that our words are one jot less figurative and more true to nature ? On the contrary, I think them more figurative and incomparably less true to nature than the language in more common use among the natu- ralists and physiologists of this country. The language just quoted is used for the express purpose of keep- ing out of sight an intelligent First Cause ; while those who have invented it are constrained to deify the dead elements ; forgetting all the while that they have on every side of them, and within themselves, the pheno- mena of mind as well as of matter ; and that every material structure or material change produced by man, and bearing any similitude to the mechanical organic structures subservient to life, is the result of design and will. So intimately are the proofs of design and pur- pose woven into the frame- work of organic life, that, spite of themselves, the modern materialists often find it impossible (as they themselves allow) to describe the phenomena before them, without falling into language implying the reality of those very final causes which XIV PREFACE TO THE FIFTH EDITION. they have in theory denied. And let not this fact be ascribed to an imperfection in the words of daily use ; but rather let it be appealed to as a proof of nature's teaching, and a true reflexion of her image by the mind of man, before that mind has been warped by any theory. (3) Of organized beings we know the beginning and the end, and we know the leading purposes to which their organs are subservient. Hence in specu- lating about the functions of organic structures, we may often use the doctrine of Final Cause as the foundation of our reasoning and the source of true induction. This we cannot do in questions that are purely physical : for while we contemplate any great physical law we neither know its beginning nor its end ; neither do we comprehend its whole purpose. Thus, while analyzing the properties of light by direct experiment, we should only desert the true road to discovery were we to turn, aside to consider the adaptation of light to our wants ; or the anatomy of the eye, and its fitness to convey the impressions of light to the visual sense. Bacon saw this distinction clearly, and wrote well upon the misapplication of final causes. Could he have prophetically anticipated the modern discoveries in physiology, perhaps his censures would have been somewhat qualified, or applied with more caution: but philosophers of every sound school will be ready to subscribe to the great truths conveyed in the following sentences {Advancement of Learning, Book ii.) : " The handling of final causes, mixed with the rest in physical inquiries, hath intercepted the severe and diligent inquiry of all real and physical PREFACE TO THE FIFTH EDITION. XV causes, and given men the occasion to stay upon these satisfactory and specious causes, to the great arrest and prejudice of further discovery. For this I find done not only by Plato, who ever anchoreth on that shore, but by Aristotle, Galen, and others, which do usually likewise fall upon these flats of discoursing causes."... . " They are indeed but remoras and hinderances to stay and slug the ship from further sailing ; and have brought this to pass, that the search of the physical causes hath been neglected, and passed in silence." " Not because these final causes are not true, and worthy to be inquired, being kept within their own province; but because their excursions into the limits of physical causes hath bred a vastness and solitude in that track. For otherwise, keeping their precincts and borders, men are extremely deceived if they think there is an enmity or repugnancy at all between them;" " both causes being true and compatible ; the one de- claring an intention, the other a consequence only." (4) While considering the orderly movements of nature, we speak of second causes, and our language defines correctly the manner in which the phenomena of nature are reflected in the human mind. But how did these phenomena begin, and by what power were they first set in movement ? These questions inevitably lead us to a conception of a creative power of nature, quite distinct from the vulgar operations carried on before our eyes : and thus are we led to speak of the creative power, as well as of the sustaining power of God. These ideas are distinct ; and to confound them under XVI PREFACE TO THE FIFTH EDITION. one general expression would only be a denial of our nature, and an utter confusion of thought, in our use of general terms. One expression tells us of the beginning of natural phenomena, the other defines their con- tinuance in subordination to law. It may be true that we can form no adequate conception of creative power ; neither, on the other hand, have we any adequate conception of the sustaining power, whereby the order of the natural world is upheld. It may also be true that in the mind and will of the intelligent First Cause there is no distinction between the exercise of a creative and a sustaining power. Of this we know absolutely nothing ; and what do we gain by such a speculation ? It is irreverent, and out of the reach of sound philosophy : for we cannot, to use the words of Bacon, " fly up to the secrets of the Deity by the waxen wings of the senses. 1 '' When applied to nature all our language is inadequate, and but feebly shadows out such ultimate truths of the material world as would express the will and purpose of the great First Cause. But our knowledge is not unreal because it is limited ; provided it be only the expression of that form of truth which defines the reflexion of the natural world in the mind of man, while he is honestly employed upon the materials sur- rounding him, and neither forgets his own faculties, nor oversteps the evidence that is before him. To meet such views as these, it has been affirmed, that we behold in nature only a chain of second causes of which we know neither the beginning nor the end ; PREFACE TO THE FIFTH EDITION. XVH that we have no right to speak of a Creator or of a creative power; because the links of nature's chain may be infinite in number, and the order of nature may have been eternal. With such a view of nature we may end in downright atheism ; or, if we accept the indications of intelligence in the natural world, we may perhaps advance one step farther, and try to satisfy the longings of the mind in some cold scheme of pantheism. As a matter of fact, views, like those just pointed at, have been brought forward again and again by men who have denied the being of a God ; or, if they could not bring themselves so far to belie their inner nature as to deny the being of a God, were at least resolved to deprive him of his personality, of his creative power and will, and of his providential government. To combat such opinions is not the immediate purpose of this Preface ; for I wish to deal with facts rather than opinions. Whatever semblance of truth they may have, while we arrest ourselves among the laws of dead matter, they are utterly without meaning when applied to the forms of organic life : for it is now beyond dispute, and is proved by the physical records of the earth, that all the visible forms of organic life had a beginning in time. To have established this point is v the glory of Geology. §2. Theory of Spontaneous Generation, Transmutation of Species, fyc. To combat or explain away the previous conclusion a new scheme of nature was invented. It was con- XV111 PREFACE TO THE FIFTH EDITION. tended that we know nothing but second causes, and that they are all in all — that the commencement of organic life was nothing more than one of the material changes in the endless cycle of movements going on continually before our eyes — a new material conbination produced by the elemental powers of the natural world ; and as purely natural as any new mechanical deposit or any new chemical combination. This view of the commencement of the organic world was called spon- taneous generation. But our theorists were not content to rest at this point. They further assumed that the humblest forms of organic life, having thus begun, had also a natural tendency to breed upwards, so as to ascend (by a law of progressive development) on a natural scale of organic forms : — that a monad thus passed by natural means (and by natural means only) into the more com- plicated form of some zoophyte — the zoophyte into a mollusk — the mollusk, by a like succession of natural steps, into a fish, a reptile, a bird, and a mammal : — and lastly, that by a like natural progression (in which all idea of creative power is excluded) some inferior mammal passed into a monkey, and a monkey into a man. The successive changes, implied in this theory, were not sudden, but slow and gradual, and brought about, during the lapse of ages, by the insensible sliding of one species into another. Thus by the simple operation of second causes we obtain, on the principles of this theory, two classes of phenomena, one defined by the words spon- taneous generation, the other by such terms as progressive PREFACE TO THE FIFTH EDITION. , XIX development, or transmutation of species : and thus we are supposed naturally to account for all the phenomena of organic life and the whole sequence of animated nature. The authors and early defenders of this theory were, perhaps without exception, unbelievers in every form of Revealed Truth. They were materialists in the rankest sense of that term. They denied all distinction between material and moral phenomena — regarding them both as nothing more than the varied mani- festations of the powers of second causes. Most of them formally denied all proofs of design in nature, and all in- dications of an overruling Providence ; and thus struck at the foundation of Natural Religion. But a doctrine may be true, and yet may be turned to evil purposes. The first questions for discussion are the following — Is this doctrine true I Has the animal kingdom been first produced by spontaneous generation, and afterwards per- fected by transmutation and progressive development t The Author of the Vestiges of the Natural History si of Creation, has adopted the whole scheme which has been sketched in the preceding sentences ; and to a comment on his principles I must devote a portion of this Preface. His work is written in a dogmatic spirit, and in good language. It is written also in the words of seeming reverence, and takes for granted the indications of a Final Cause ; though its principles and language were invented and affirmed by those who did their best to cheat us out of our conceptions of a Creator, and denied the whole doctrine of Final Causes. The Author proved, by the numerous mistakes of his XX PREFACE TO THE FIFTH EDITION. early editions, that he was neither well acquainted with the first principles of physics, nor well read in any sound work on physiology. Hence, his book was re- ceived with no respect and favour by men of science. On this point I can, even now, speak with the utmost confidence. But it was new in the popular literature of this country; and more than this, it was systematical and positive, and seemed to offer to the smatterers in natural science a kind of short and royal road to uni- versal knowledge. By such persons it has been re- ceived with no common favour. The Author is not only unacquainted with any of the severe lessons of inductive knowledge, but has a mind apparently incapable of comprehending them. Without this supposition it would be hardly possible to acquit him of insincerity. No moral accusation is, however, brought against him. He writes in good faith, and had imposed upon himself before he un- consciously attempted to deceive others. The misinter- preted facts, to which he first clung to support his argument, may be rescued from his grasp, one after another. But he will not easily change or modify his first opinions : for, speaking of specific transmutations, he has told us — that though there never may have been an instance of it since the beginning of the human race, "yet the doctrine may be shewn, on grounds altogether apart, to have a strong probability on its side."..." And though this knowledge were never to be clearly attained, it would not much affect the present argument, provided it be satisfactorily shewn that there PREFACE TO THE FIFTH EDITION. XXI must be some such power within the natural range of things. 1 ' Satisfactorily shewn that there must be some power in nature independent of our experience ! The Author while using this language is speaking of second causes ; and seems never to have learnt that there are not, and never can be, any probabilities in nature that are not suggested by experience. I now pass on to his system. (1) He assumes the truth of the Nebular Hypo- thesis. It is his first link in the chain of natural causes. But has this hypothesis been confirmed by the progress of discovery ? Is it passing into the con- dition of a sound physical theory? I think the con- trary. On this subject I request the academic reader (for to such readers the following little work is still addressed) to turn to note (D) of the Appendix (infra, p. 118*.) I cannot pause to notice the author's vio- lation of every rule of sober and severe induction in his extravagant extension of the hypothesis. (2) After a series of natural transformations, he at length finds a world fit for the support of animal life, and animal life begins. Spontaneous generation and a gradual transformation of species on an ascending scale are now to bring about all the phenomena of the organic world f. He allows of no creative will distinct * See also Supplement to the Appendix No. I. •f In using these words I refer to no particular scheme of arrangement for the organic kingdoms. The reasoning of the text applies to every scheme, linear or circular, simple or complicated. Every scheme, however, implies an ascent from beings of a low organic structure to beings of a higher ; and it is a matter of indifference to the argument, whether this ascent take place upon one line or upon a thousand. XX11 PREFACE TO THE FIFTH EDITION. from the vulgar action of second causes — no distinc- tion between mind and matter — material and moral : — and man (with all his powers, physical and intellectual, his responsibilities as a social being, his expectations of moral progress, and his hopes of future good) is, so far as regards causation, a phenomenon of the same order with the incrustation on a culinary vessel, the salt formed in a chemist's laboratory, or the crystal in a mineral vein. Should we gain in clearness of con- ception, or be more philosophical in our use of general terms, by linking together (as the supposed products of a common material causation) phenomena so different in kind, and so widely asunder in every manifestation they make to the mind of man ? Is there any sobriety or truth in such a scheme as this ? On the contrary, I think it shallow, mischievous, and untrue. (3) All natural knowledge is based on inductive reasoning. We have learnt to comprehend the mecha- nical movement of the heavens by first learning the laws of motion upon the earth. In like manner, we have learnt to speculate securely on the functions of organized being, during the old conditions of the earth, by first studying the laws of organic life among the phenomena of living nature. In every instance we must begin with what is known and present to us, before we can speculate about what is unknown and remote. To this rule we know of no exception. (4) What proof, then, have we of the doctrine of spontaneous generation in the living world ? In replying that we are utterly without proof, I only state PREFACE TO THE FIFTH EDITION. XX111 my firm conviction. All the Author's instances are drawn from the dark corners of nature's kingdom, where it is almost physically impossible to trace the progress of her workmanship. Sober philosophy would tell him, in such cases, to be guided by analogy ; and all analogy is against him. We may presume that he has selected such instances as are best suited to fortify his argument. And what are they? — The Hydatid^ which sometimes affects the domestic pig, and is sup- posed not to attack the wild animal ; the Larva of the (Enopota cellaris, which lives nowhere but in wine and beer ; an insect which feeds only on chocolate ; a Tinea, which only attacks dressed wool ; and the Pimelodes cyclopum, which are only found in subterranean lakes in the old craters of the Andes. How are the negations implied in the three first instances to be proved 1 How, for example, is it possible to prove that no wild boar is ever attacked by the Hydatid f The domestic animals are constantly before us, the wild animals are not. The Tinea attacks the fleece, as well as the prepared and manufactured wool. And were the Author's statement true to the letter it would start no new difficulty ; for sheep in the wild state must cast their wool, which, when scoured by the elements, might become a proper nidus for the Tinea, The case of the Pimelodes cyclopurn is only one example, out of many, of animals with a con- fined habitat : neither is it fairly stated ; for those who have described these fishes tell us that they are found in the streams on the mountain-sides as well as in the old craters of the Andes. They are not more difficult XXIV PREFACE TO THE FIFTH EDITION. to account for than the trout and other fishes so com- monly found in the high mountain-lakes of Europe. The Entozoa are, beyond comparison, the cases most difficult to account for : but the whole history of many species has been well explained in conformity with the common laws of generation : and, speaking generally, we may ask, if these creatures spring spontaneously without ova, how comes it to pass that nature has pro- vided a means for the continuance of their species, and that some of them are almost incredibly prolific * ? But it was affirmed, within the last few years, that a new animal had been produced by a direct galvanic experiment, and without any pre-existing germs of animal life. If so, we should have one instance of the commencement of organic life, in conformity with the hypothesis of spontaneous generation. It turned- out, however, that this new marvel of nature's chemistry was but an old and wellknown species of Acarus, of which the ova, in tens of thousands, probably existed in the dusty corners of the very room where the first experi- ments were carried on. The creatures thus produced were not (as they ought to have been) low in the or- ganic scale, but were of a very complicated structure ; and one of the pretended creations was a female well filled with eggs. If galvanism could thus create animals, no wonder it should also exercise over them a fecun- dating influence ! But is there so much as one good * See Professor Owen's Lectures on the Invertebrate Animals (1843, pp. 76—81), and the Edinburgh Review (July, 1845, pp. 68—72). The ova in one individual of the Entozoa amount to sixty-four millions ! PREFACE TO THE FIFTH EDITION. XXV physiologist or chemist who now adopts the first in- terpretation of these galvanic experiments ? I believe not so much as one. Ridicule is the only weapon we can condescend to use against the outrage on common sense and universal experience implied in this mockery of a creative power. One thing, however, is proved by this history, that to be an intrepid vindicator of rash hypotheses a man must be first endowed by nature with an ample capacity of belief*. (5) Have we any proof of specific transmutations in the living world \ We have not, so far as I under- stand the question, so much as the shadow of any proof of them. The constancy of organic forms — like species producing like according to a fixed law of generation — is the obvious and certain fact. These laws are to the organic world what the laws of elective affinity are to chemical combinations. Varieties there are — the limits of species are not well known — the riches of nature are so great that, in the almost boundless varieties of ani- mal forms created on a common plan, one species often comes close upon another. As an inevitable conse- quence, naturalists have made many blunders ; and their vanity may sometimes have led them to give new spe- cific names, where the new names were not called for. But the mistakes of naturalists alter not the laws of nature. Art has been pushed to the utmost in modify- ing the natural forms of organic life : but not so much \ as one true specific change has been ever brought about, so as to raise the progeny of any known animal to a * See Supplement to the Appendix No. II. S. D. c XXVI PREFACE TO THE FIFTH EDITION. higher grade on the organic scale. These are the broad conclusions we arrive at from all the facts and analogies offered to our senses. In this instance it will not serve our purpose to entrench ourselves among the dark corners of the animal kingdom ; where, (as in the case of the Entozoa^) from the inevitable want of evi- dence, we may, by casting away analogy, affirm that generation is ambiguous, and that species are inconstant. The Author's theory demands specific transmutations on the whole ascending scale, from a monad to a man. To suppose that specific transmutations are now going on at the bottom of the scale, where our senses fail us, and we can have no good evidence of the fact ; while no transmutations are going on in the upper steps of the organic scale, where we have good evidence, is to stultify the whole argument, and to suppose an inconstancy in nature^s workmanship, abhorrent from any conception we can form of a true organic law. A good theory embodies in verbal propositions our conceptions of natural laws ; and these conceptions are all based on observation, experiment, or good analogy. Does the hypothesis of spontaneous generation and trans- mutation of species deserve the name of a theory ? It is not suggested, but contradicted, by the broad and ob- vious facts of nature ; and I know of no good analogy to help it out. A hypothetical spirit may do good service, provided it urge us on to make new experiments ; but if we rest content with it, and, above all, if it lead us, as it has too often done, to shut our eyes against facts, and to take from nature no response but such as suits our PREFACE TO THE FIFTH EDITION. XXV11 fanatical belief of what nature ought to be, it must do deadly mischief to the cause of inductive truth. $ 3. Foetal Transformations and their bearing on the Theory of Development. Are there any other facts in living nature bearing on the hypothesis of development as stated by the Author of the Vestiges f He dwells on the transforma- tions exhibited by every vertebrate animal during its foetal life — from its first existence as an animated germ, to its full maturity of organic structure. If it be true that all the higher animals (of course including man) have, during their early life, gone through a series of transformations whereby they have been made to pass through all the successive inferior Classes in the great ascending scale of nature ; why should we not suppose that in the universal womb of the living world one species may be transformed into another on a similar ascend- ing scale ? Taking it at the very best, the assertion implied in such a question is based only on a vague analogy, which may help us to turn a figurative sen- tence, but can never serve a higher purpose, or take the place of fact as the support of a sound theory. The broad intelligible fact is this: — whatever transformations their progeny may go through while in the foetal state, like species continue to produce their like. " By no artifices of human skill (and artifice has not been want- ing) has the animated ovum of one species been deve- loped into another ; by no artifice has the ovum of any known species been permanently developed into any c2 v XXV111 PREFACE TO THE FIFTH EDITION. new species ; by no continued operation of analogous con- ditions, however carefully conducted, have the ova of different species been developed into animals of one kind." (Dr. Clark.) Nature is true to her work, and will not turn aside to follow the crooked track of an hypothesis. But is it true that the higher animals do undergo during their fcetal state a transformation from one organic class to another, on a regular ascending scale? Is it true, for instance, that the foetus of a man, during the successive periods of gestation, is a monad, a polype, an insect, or a cephalopod? Is it afterwards a fish, a reptile, a bird, a beast, a monkey, and lastly a human being with a permanent organic form * ? It is impossible to discuss such questions to much purpose within the limits of this Preface. All I pretend to * This question is discussed, in a very condensed form, through twelve pages of the Edinburgh Review, (July, 1845), to which I may refer the reader. The Reviewer borrowed the best part of his argument from an excellent Memoir on Fcetal Development, read before the Cambridge Philosophical Society by Dr Clark, in the early part of 1845. I cannot withhold an earnest wish that he would publish this Memoir in a somewhat more expanded form, and with anatomical illustrations. Should any Reader wish to consult the Article in the Edinburgh Review, just referred to, I may inform him that it is very carelessly printed, and that its Author seems not to have well understood the mystery of correcting proof-sheets. The following errata will justify this remark — E. R. No. 165, p. 10, 1. 11, for Mackay read Macleay, and 1. 18, for analyses read analogies : p. 21, 1. 25, for positions read portions : p. 27, 1. 15, and 1. 32, for Bailey read Baily : p. 31, 1. 16, for original read natural : p. 42, (line 2 from the bottom), for radiata read articulata — the word is correctly written, 1. 19 of the same page: p. 56, 1. 7, for quane read quant; and 1. 8, for cretes read cries : p 59, 1. 34, and 1. 41, for Bimana read Quadrumana ! ! Were not the words written correctly on other pages one might conclude that the Reviewer gave four hands to men, and only two to monkeys : p. 66, 1. 11 from the bottom, for hecomes read become : p. 68, 1. 30, and 1. 33, for Hyatid read Hydatid: p. 74, 1. 24, for spermatazoa read spermatozoa. PREFACE TO THE FIFTH EDITION. XXIX do is to state a series of fundamental facts, out of which, when illustrated by anatomical designs and properly expanded, the true answers to these several questions may be drawn. First. There are certain phenomena which seem to imply a formal or specific character in the very begin- nings of mammal life. I allude to the spermatozoa, first seen at the age of puberty ; ami if they differ speci- fically in different animals, then (whatever may be the office of these mysterious bodies — whether they act as mere stimulants, or in whatsoever way they act) there is an end of all approach to specific identity in the first beginnings of organic life. Secondly. Let us suppose animal life to have begun. The first changes of the organic germ within the ovum of a mammal do resemble those observed in what has been called the " fissiparous generation " of the lowest grades of the animal kingdom. But these resemblances soon after cease ; and the organic globules, by some mysterious bond of union unappreciable by microscopic sense, arrange themselves in two nearly parallel rows ; and thus we have the first rudiments of a backbone, and a continuous spinal chord. But during the elaboration of this early organic structure, no anatomist has ever observed any succession of changes bringing the nascent embryo into a true anatomical similitude with the Radiata, Articulata, or Mollmca. Thus are three great Divisions, or Sub-kingdoms, including fifteen Classes in the organic scale (as given in the system of Cuvier) passed over without any corresponding foetal type. XXX PREFACE TO THE FIFTH EDITION. Assuredly this fact, were there no other, is fatal to a theory of regular progressive transformations ; which starts from this position — that the organic germs of all animals are alike — and that man, and all the other higher animals, pass, while in the womb, through all the successive conditions that are permanent in the lower Classes of the great organic scale of nature. Thirdly. There runs through all animated nature a grand unity of plan and purpose ; were it not so, comparative anatomy could never have risen into a science. So much of similitude is found even among animals widely placed apart, that organs subservient to a common purpose may be brought into anatomical comparison, and often described under common names : and this is true not only of the perfect animal frame- work, but is true also of the successive organic changes during the foetal state. But these resemblances produce no confusion of species, nor do they interfere with the clear distinctions between separate organic types. There are two very distinct sets of changes, follow- ing in regular succession, during the foetal state of all the higher animals. " In the first set are laid down the animal organs, the nervous system and organs of motion, as well as the intestinal canal and its appen- dages (sometimes called the vegetative organs), and a kind of intermediate system evolving gradually the heart and blood-vessels. The combination of all these is the true embryo state of the animal. The second set of changes produce the perfection of the animal, and determine its sex. These belong to what is called PREFACE TO THE FIFTH EDITION. XXXI the larva state. Now the embryo state and the larva state are both passed in ovo by mammals and birds (and some vertebrates of another class) ; but the larva state is passed out of the ovum by batrachians, fishes, and most of the invertebrates*." During the progress of these changes, tufts and gills are gradually formed on the " branchial fissures" of batrachians and fishes ; and when this structure is sufficiently advanced to enable these organs to discharge their offices, the growing animals are forced, by anatomical necessity, to quit the ovum, and begin an independent life. But during the corresponding period in the gestation of a mammal, no tufts or gills are found in the (so-called) "branchial fissures 1 ' of the embyro. No microscopic power has ever shewn the minutest germination of branchial tufts or gills. The extremities of the fcetus are ill-defined, and might in popular language be called fins or paddles : but they have not the anatomical struc- ture of true fins ; and the embryo breathes not, for a single instant, by help of gills. It is not, therefore, true, that the foetus of a man, or any other mammal, ever passes through the animal conditions of a fish : and here again the theory of progressive foetal development, from one corresponding germ through a succession of common types, breaks down, and is untrue to the work- manship of nature. Fourthly. Do men, or any other of the higher ani- mals, pass, during their foetal growth, through the condi- tions of reptile life ? The grand distinctions between the * Memoir, by Dr Clark. XXX11 PREFACE TO THE FIFTH EDITION. organic life of a reptile, and that of a bird or mammal, arise out of the modifications of the heart. This truth becomes obvious when we consider that the nutriment of the whole body, and the secretions of every organ, are drawn directly or indirectly from the blood. No reptile has the perfect double heart of a bird or mammal. What, then, are the organic transformations in the hearts of birds and mammals during their foetal growth I To prevent mistake, I will again quote the Memoir of Dr. Clark : " The first rudiment of the heart appears in a single tube, and it gradually becomes bent like an Italian S ; and it then makes three swellings which are afterwards, in mammals and birds, to become the two auricles, the two ventricles, and the aorta with the pul- monary artery. This led to the belief that the swelling for the auricles was first divided into two compartments by a septum ; and that the swelling for the ventricles was divided at a later period of foetal life. This belief is, however, contrary to fact. The septum is formed in the swelling corresponding to the ventricles a consider- able time before it is formed in that corresponding to the auricles. So that, for a period, the heart of a human foetus (as well as that of other mammals and birds) has one auricle and two ventricles. Hence it does not pass through the form which is permanent in the Amphibia; but it does pass through a form not found permanent in any known creature. This grand correction of an old mistake we owe to the concurrent labours of Valentin, Rathke, and Bischoff, who stand in the first rank of discoverers; and no good anatomist has pretended to contradict PREFACE TO THE FIFTH EDITION. XXX111 them. The hearts of birds and mammals do not, there- fore, pass through forms which are permanent in fishes and reptiles* ." Again, therefore, the theory of progressive foetal development breaks down ; and whatever sem- blance of reality it may have in the eyes of those who amuse themselves with tracing similitudes among the ill-defined and immature organs of foetal life, the theory is anatomically untrue. Fifthly. As the foetal forms of the higher animals approach maturity, and become gradually capable of breathing air, and supporting an independent existence, they are still bound up in anatomical conditions which are essential to their continued life, and fix an impass- able barrier between one species and another. " At the period of foetal life, 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 foetal development hot-blooded quadrupeds are breathing by allantoid and placenta jointly ; while man is breathing by placenta alone. These are essential foetal differ- ences connected with the last perfection of animal struc- ture ; and they form a wide anatomical separation, so as to bar all interchange or confusion of organic type." (Dr. Clark). To make these assertions clear would * The above passage first appeared in the Edinburgh Review, July 1845, p. 80 ; and I am happy to quote it here on account of its great value, and also because it contained, 1 believe, the first allusion, made by an English writer, to a very remarkable discovery of the German anato- mists. I need not, perhaps, inform the reader that, in the normal type, a fish's heart has one ventricle and one auricle, and that a reptile's heart has one ventricle and two auricles. XXXI V PREFACE TO THE FIFTH EDITION. require a series of good anatomical drawings : but enough has been stated for my purpose. I have no wish either to extenuate or exaggerate the dealings of nature : but what has been stated crushes to atoms the theory of The Vestiges, so far it as has been drawn from the progressive forms of foetal life. There is one grand fallacy which has warped all the descriptive writings of our Author's school. To serve the purpose of an hypothesis they have described the foetus, in the successive stages of its growth, only by its central portions ; and not by its whole mass, including its organic appendages. But it cannot be separated from these appendages without instant death, unless it have reached that maturity of structure which will enable it to maintain an independent life. Had they reference only to existing conditions of foetal life, we might perhaps suppose, with a semblance of reason, that different Classes of the animal kingdom were not merely laid down upon the same general plan, but that they passed, by insensible gradations, into one another. As a matter of fact, however, to which there is no ex- ception, these fcetal appendages are not defined by existing conditions. Their office is to perfect the ani- mal form ; they are true prospective contrivances, im- plying, under strict anatomical necessity, a subsequent and more perfect condition of organic life. We cannot hatch a rat from a goose's egg (one of the Author's pleasant dreams) ; because, during every stage of incu- bation there are organic contrivances within the egg which have a prospective reference only to the struc- PREFACE TO THE FIFTH EDITION. XXXV ture of a bird, and apply not to that of any mammal. There is, therefore, so far as we can comprehend it, no obscurity in this part of nature^ workmanship, nor any semblance of confusion or structural interchange be- tween the different Classes of the living world. Again, there is no intelligible contrivance for the production of a new species during the progress of foetal growth. Many larvae (for example the tadpole) can, for a time, support an independent life. But such animals are immature, and, without one exception, unfruitful. Their life may be destroyed, or, within limits, may be lengthened. They may be well or ill-fed, they may be large or small, but we cannot change their nature. Speaking of the tadpole, our author tells us that (under artificial treatment) "this progeny of a Reptile literally becomes a Fish; and transition of species is thoroughly realized, although in retrogres- sion *." We deny that in this (or any similar) instance there is even an approach to a specific transmutation. The tadpole contains not the organs most essential to the structure of a perfect fish : and if its organs be defective on the one hand, so are they excessive on the other ; for it contains within the framework of its body certain organic appendages from which it cannot be separated without death; and these appendages, by a strictly anatomical necessity, produce in due time the mature organic structure of a frog. The loose un- scientific statement of the Author may be fitted to startle a superficial reader, but it contains not the * Vestiges of the Natural History of Creation, 6th Edition, p. 226. XXXVI PREFACE TO THE FIFTH EDITION. elements of exact truth, and is only an example of that grand anatomical fallacy to which I have before alluded. Again, the Author tells us (p. 224), " that we see nature alike willing to go back and to go forward. Both effects are simply the result of the operation of the law of development in the generative system." No one denies the great modification of specific types from a change of external conditions : but when he appeals to a law of development in the generative system which produces a change of species, either on the ascending or descending scale, we can only state in reply, that we utterly deny the existence of any such law, or of a single fact whereon to build it. So far from being based on a wide induction of facts, (and without such induction the verbal expression of a material law is no better than a mockery), the Author has not advanced so much as one unequivocal instance in support of it. The voice of all nature is against him. But he has published his Explanations, a Sequel to the Vestiges, fyc, wherein he attempts to vindicate his views on the foetal question. However much I may wish to avoid details, I will notice these Explanations in a few sentences. (1) Has he answered the Reviewer's statement — that, in the very beginning of foetal life there are phe- nomena that seem of themselves to imply definite and specific differences \ He has not, I believe, even made the attempt. (2) Has he answered the objection of the Re- viewer — that, during the early progress of foetal life, in PREFACE TO THE FIFTH EDITION. XXXV11 animals of the higher grade, three great Divisions of the animal kingdom are passed over without any cor- responding foetal type ? He has made the attempt, and failed. We learn, he tells us, from the Bridgewater Treatise of Dr. Roget, that animals of a high grade exhibit, during their early fcetal progress, u a marked resemblance to the lowest animals of the same series." This may be true in a popular sense ; but it is not anatomically true that these resemblances produce any confusion of species. The quotation proves nothing to the Authors purpose, and I know that Dr. Roget repudiates its application. Again, he tells us, " the Reviewer states what is not true, if any faith is to be placed on the first authorities of the age ... for have we not seen Mr. Owen affirming that the human embryo is first vermiform?" In the sentence from which this word is taken Professor Owen wrote in figurative language, and never meant to be anatomically exact. The first " organic streak " (or rudiment of a back-bone) may well be called vermiform : but it has not the structure of a worm ; and it has ap- pendages, that are as true a part of the nascent foetus as the " streak," and involve a development of the higher grades of animal life. I have consulted Professor Owen, more than once, on the very point in question, and he confirmed every atom of the Reviewer's state- ment : nay, so exactly did his language agree with that of the Reviewer, that one seemed almost the echo of the other. With the interpolation of one single word (to prevent a quibble) I can, with the utmost confidence, XXXV111 PREFACE TO THE FIFTH EDITION. repeat the assertion of the Reviewer — that among the vertebrata, during the early fcetal progress, " no physio- logist has observed the shadow of any change assimi- lating (anatomically) the nascent embryo to any of the Radiata, Articulata or Mollusca." (3) Has the Author replied to the statement of the Reviewer — that the foetus of a mammal never breathes by gills, and is never, for an instant, in the true anatomical condition of a fish I He has done no such thing. He has contented himself with repeating his early blunder. (4) Has he replied to the argument of Dr. Clark ; and especially to his statement respecting the fcetal changes in the heart of a mammal ? He has not, so far as I know, even made the attempt ; and in his sixth edition (Vestiges, p. 207) he has gravely repeated his old blunder, forgetting the labours of the great anato- mists formally quoted against him by Dr. Clark ! (5) Has he replied to the concluding remarks of Dr. Clark on the apparatus supplied by nature for the full maturity of the fcetal form ! They are all passed over. But he informs us (Explanations, p. 1 08) that his theory has been misrepresented. He only meant to state that " there is a resemblance in general character between the particular embryotic state of being and the mature condition and form of the appro- priate inferior animal, V &c. He is, undoubtedly, the best interpreter of his own words : but they sounded differently in the ears of all who read them ; and by him- self they were applied, again and again, as if they were used in the very sense given to them by the Reviewer. PREFACE TO THE FIFTH EDITION. XXXIX While speaking of the foetal changes of a man, the Author tells us, in his last edition, " that the organic structures pass through conditions generally resembling a worm, a fish, a reptile, a bird, and the lower mam- malia," &c. But he has not always expressed his meaning with like caution ; and I may remark that " general resemblances" will not serve his purpose. His scheme of development supposes that the foetus passes through the ascending organic scale — that it may be thrown off by abortion, and live and propagate its likeness on an inferior grade — that a Reptile, in this way, may produce a Fish, or a Mammal may produce a Reptile. On the other hand — that by improved incu- bation or gestation the offspring may rise on the organic scale above the parent's grade — that a goose's egg (for example) may produce a rat. This theory (if it deserve the name of theory) has no meaning, unless we take for granted that the foetal changes of a mammal do produce something more than general resemblances. They must produce foetal conditions identical with the several grades of animal life, which they are, by the hypothesis, assumed capable of generating. It was against this view that Dr. Clark's argument was di- rected : and, so far as I know, not the shadow of a reply has been given to it. But the Author adheres to his scheme, and will adhere to it so long as a new hypothesis can give it any semblance of consistency. Should every alleged fact be smothered under the weight of opposing evidence it matters not. The doc- trine of specific transmutations, and of a generative law XI PREFACE TO THE FIFTH EDITION. of foetal development, whereby a pair of animals may produce a progeny either lower or higher than them- selves on the great organic scale of nature, may still be upheld by our Author : for he ventures to tell us, " though no such changes have taken place since the beginning of the human family, and though this know- ledge were never to be clearly attained, it would not much affect his argument, provided it be satisfactorily shewn that there must be some such power within the natural range of things ! " I need not tell the academic reader that this is not written in the spirit of in- ductive truth. To strive against it would be a waste of strength. We cannot wrestle with a cloud. I will endeavour to conclude this part of my Pre- face with the following general summary. From the harmony and order of the material world, we infer the existence of an intelligent power superior to the dead matter which surrounds us. This is admitted by the Author of the Vestiges : but in making this admission he is in direct antagonism with the whole school from which he borrows his philosophy. From the adaptation of the several parts of nature to one another, we infer a prescient wisdom in the great First Cause. This First Cause we clothe with personal attributes ; we compre- hend them all under our conception of the Godhead ; and in this way we refer all the phenomena of the visible world to the fiat of his will, and the continued exercise of his sustaining power. In drawing this conclusion we use the voice of Nature, and we only speak of her as she is reflected in the mind of man. For man, by PREFACE TO THE FIFTH EDITION. xli the exercise of his own forethought and will, can pro- duce a series of orderly phenomena — feebly resem- bling the works of God, however inferior to them in vastness, in complexity, and in the sure indications of power and wisdom : and humble as man's faculties may be, he does know how to separate such phenomena, wheresoever he meets with them, from the results of accident, and from the rude effects of second causes that come not under law, and are unmodified by the prescient will of beings like himself. In no part of nature are the wisdom and provident care of God more clearly seen than during the pro- gress of foetal life. The eye is formed in the dark recesses of the womb before light has ever touched the nerves of sight. The ear also is prepared in dark- ness, while the nascent being is surrounded by water, and before the pulsations of the air have ever reached its bodily substance. Neither the immediate wants of the growing embryo, nor the conditions of the sur- rounding matter, imply, by any conceivable necessity, the existence of such organs as the ear and the eye : and we but mock the intellect of man when we tell him that they are produced only by " the elective af- finity of organic elements,'' 1 and that they may be com- pared (as phenomena of the same order) to the mecha- nical actions of matter upon matter, or to the results of a chemical combination. Whatever there may be that is either chemical or mechanical in our fcetal organs of sense, they shew prospective contrivances which enter not into our conceptions of what is chemi- s. d. d Xlii PREFACE TO THE FIFTH EDITION. cal or mechanical, and have reference only to future conditions of life after the foetus has passed into what may be truly called a new living world. In like man- ner, while in the foetal state, neither man nor any mammal has need of a double heart. The foetus is resting in a dark chamber surrounded by a watery fluid ; and a simple heart we believe (on the analogy shewn to us by the hearts of fishes) would best suit its state of being. A simple heart is given to it, not however the heart either of a fish or a reptile ; but a heart with a structure of its own, and with appendages — a true and inseparable portion of itself — whereby a new double heart is gradually laid down and per- fected. When this complicated apparatus has reached perfection, and the foetus becomes capable of support- ing an independent life, then it passes into the air, and the double heart begins from that moment its predestined organic movements. I have only stated facts which have been stated a thousand times before. I have stated them as plainly as I can ; and I have given them their true physiological and moral meaning. 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. This is the voice of inspiration, and reaches the profoundest depths of true philosophy. The knowledge of man can neither add to its meaning nor diminish its strength. It teaches not that the moral parts of our nature are sunk under the material ; neither does it tell us that the material are beneath the contemplation of the moral ; PREFACE TO THE FIFTH EDITION. xlift but it unites together the moral and material in bonds which the power of man will never tear asunder. All living Nature then, so far as I can understand her language, or can read the interpretations of it by other men, contradicts the theory of spontaneous generation and progressive development. Spontaneous generation (in our Author's sense) has not one good unambiguous fact to rest upon. The theory of develop- \ / ment has no firmer support in^nature: and the only pretended fact which has any clear and unequivocal bearing on the question, and is put forth by the Author of The Vestiges, with the view of destroying the separa- tion between vegetable species, turns out to be nothing better than a misconception and a blunder*. It has been said, however, that animals undergo a progressive development while they pass through their successive foetal conditions in the womb. True ! and many of them, while in the larva state, leave the ovum, and are enabled for a time to support an independent life. But larvw, when they leave the ovum, have no sexual development ; and can never without a miracle (for what is a miracle but a viola- tion of an ascertained law of nature ?) have the power of generating any new continued forms of animal being. And were it true, by a miracle in nature, that any one of them were suddenly endowed with this power, the development would then be on a descend- ing, and not on an ascending scale. Again, we have been told that animals may, under favourable conditions, * Supplement to the Appendix No. IV. d 2 xliv PREFACE TO THE FIFTH EDITION. and by a longer period of gestation, produce some being of a higher order than themselves : that a beast (for example) may in this way be hatched from a bird's egg; and that woman may hereafter make perfect the organic scale, by producing some being of higher attri- butes than man ! What beings may be produced out of the abortive imaginations of the human brain, is not a question worth one moment's pause. So far as nature is concerned, philosophy has nothing to do with what may be, but with what is. $ 4. Organic Phenomena of Geology, and general remarks on their bearing on the Theory of Development. Leaving the consideration of living nature, another question may be started : Are there, among the old de- posits of the Earth, any traces of an organic progres- sion among the successive forms of life ? I think there are such traces ; and to explain my meaning, I will quote an extract from an Anniversary Address read by myself before the Geological Society of London, in 1831. " I think that in the repeated and almost entire changes of organic types in the successive strata of the earth — in the absence of mammalia in the older, and their very rare appearance (and then in forms entirely unknown to us) in the newer secondary groups — in the diffusion of warm-blooded quadrupeds (frequently of unknown genera) in the older tertiary system ; and in their great abundance (and frequently of known genera) in the upper portions of the same series — and lastly, in the PREFACE TO THE FIFTH EDITION. xlv recent appearance of man on the surface of the Earth (now universally admitted) ; — in one word, from all these facts combined, we have a series of proofs the most emphatic and convincing, — that the existing order of nature is not the last of an uninterrupted succes- sion of mere physical events derived from laws now in daily operation : but on the contrary, that the ap- proach to the present system^, of things has been gradual, and that there has been a progressive develop- ment of organic structures subservient to the purposes of life. " Considered as a mere question of physics (and keeping all moral considerations entirely out of sight), the appearance of man is a geological phenomenon of vast importance — indirectly modifying the whole surface of the earth — breaking in upon any supposition of zoo- logical continuity — and utterly unaccounted for by what we have any right to call the Laws of Nature. If by the laws of nature we mean only such manifestations of power as seem good to the Supreme Intelligence, then there can be no matter for dispute. But in physical questions such terms as ' the laws of nature, 1 have a proper reference only to second causes ; and I may ask, by what operation of second causes can we account for the recent appearance of man*?" I wish to make no change in the previous extract. Its language might be improved, and brought into more exact accordance with the advance of knowledge during the last twenty years : but it expresses, with sufficient clearness, what may be called a great historical truth ; * Proceedings of the Geological Society. London, Vol. i. p. 305. Xlvi PREFACE TO THE FIFTH EDITION. and the words " progressive development" have (in the sentences just quoted) no reference to any theory either true or false. At the time it was written I neither be- lieved in the spontaneous generation, nor in the specific transmutations of any portion of the animal kingdom. Let no one, therefore, quote this passage without allow- ing its author to define the meaning of his own words'*. Three great divisions of the fossili/erous strata. Con- sidered under the most general and simple point of view, the fossil-bearing strata of the earth admit of an arrangement into three great divisions ; the Primary, or Palaeozoic ; the Secondary ; and the Tertiary. — In the lowest groups of the Primary division neither land- plants nor air-breathing marine animals have yet been found ; but other marine animals are found in abund- ance, and some of them are of the very highest organic type. In the upper groups of the same division we have a noble terrestrial flora; and coeval with that flora were Insects and Reptiles. In the very highest group (the Permian) bones of Reptiles had long been discovered : but remains of the reptile Class have lately been found also in the Carboniferous strata. Among the Secondary rocks — including under that name all the formations, from the new red sandstone * A historical development is, or ought to be, a record of successive facts in the past phenomena of the organic world. A theory of develop- ment may be true or false ; but must not be confounded with a mere statement of the successive facts on which it is supposed to rest. In the remaining portions of this Preface the word development may sometimes be used historically ; but the words theory of development are always used with an expressed or implied reference to the hypothesis of a progressive natural development by specific transmutations. PREFACE TO THE FIFTH EDITION. xlvH (Trias) to the chalk inclusive — we have, in addition to all the lower grades of the animal kingdom, a few Birds and Mammals. But the Birds and Mammals are so few and far between, that we can arrange them chro- nologically on no regular organic scale. Two strange genera of terrestrial Mammals shew themselves among the fossils of the lower oolites : but not one remnant of a terrestrial Mammal has been yet discovered among the higher Secondary rocks. No cetacean bone has yet been found in the lower oolites. One doubtful example of a cetacean bone occurs in the middle division of the oolites ; but this form of organic life disappears again ; and during the long epoch of the cretaceous series (forming a prelude to the tertiary system, in which mammals' bones are abundant) not one cetacean bone, or one fragment of any other marine Mammal, has yet been found. In the Tertiary division bones of Mammals occur in abundance ; and in the highest beds of the series we are introduced to many existing types of the organic world: but the remains of Man have not yet been discovered even among the highest of the regular ter- tiary deposits. It is true that the phenomena of geology are widely separated, broken, and disjointed ; and the progress of knowledge may compel us to modify some of our pre- sent conclusions, so far at least as they are built upon the assumption of negative facts. In an advancing science, our theory may be true or false, perfect or imperfect : but as it professes to start from ascertained pheno- xlviii PREFACE TO THE FIFTH EDITION. mena, so must it continue to be in co-ordination with such facts as come before us during our progress, or it is good for nothing. Do, then, the ascertained phenomena of geology sug- gest a theory of development based on any known law of organic nature ? So far as the theory is concerned the real questions for discussion are such as follow. — Are the animal remains of our successive groups of strata pre- sented to us in such an order as to suggest a theory of natural development by transmutation from one organic form to another 8 Are the Genera and Families of the old world so ill defined as to pass one into another by insensible gradations ? Are the organic intervals be- tween the different Orders and Classes of the animal kingdom so far interpolated by new forms of nature, as to lose all semblance of reality and permanence, and to shew that all our systematic lines of separation are but the artifices of immature knowledge — that Order may spring from Order, and Class from Class, in the way of natural generation ? Do the organic types of the old world follow one another chronologically, in such a manner as to arrange themselves on any conceivable organic scale, whether simple or complicated ? To all such questions I can do no more than return a most unqualified negative : and I may add, that the Genera and Families of the old fossil world are more abruptly defined, and exhibit fewer connecting links, than in existing nature. But it is, I fear, impossible for me, within the limits of this Preface, to discuss such ques- tions effectually. PREFACE TO THE FIFTH EDITION. xlix The materialist school must, in some form or other, give an affirmative answer to these questions. And how have they given even the semblance of truth to their dogmatic theory of development? By first discarding the pregnant facts of living nature — by ex- plaining the known by the unknown, and thereby con- founding the very nature of true inductive evidence. — By reconstructing, hypothetically, a chain of being out of the organic fragments of the old world ; and then taking this chain, every link of which is hypothetical, to bind together their system of nature ; thereby discarding the first principles of sound logic. — By pretending to rescue nature from the province of miracle and fable, while their system at every step is both fabulous and miraculous : for neither is it historically true to nature, nor is it grounded on any ascertained natural law. The imperfection of our knowledge may be a good reason for withholding any attempt at theory : but if we do venture to theorise it must be in conformity with such results as science has established by firm evidence. And, assuredly, the imperfection of our knowledge can never justify us in publishing our idle dreams, and then trying to make all nature bend before them. The materialists have not, however, stopped short in the exhibition of bad logic : they have given us both an imperfect, and an erroneous enumeration of facts and phenomena : and, worse still, they have so dis- turbed the chronological order of phenomena, as to gain a response from Nature the very opposite to that which she addresses to our senses. I accuse not this 1 PREFACE TO THE FIFTH EDITION. school of bad faith ; but I do accuse them of a spirit nearly touching on fanaticism. With incomparable cre- dulity in the admission of any story that seems to make for the honour of their idol, they are deaf to the plain speaking voice of Nature. Hypothesis is to be upheld, while facts are to be kept in abeyance. " My system may be true," says the Author of The Vestiges, M though one half the illustrations presented at its first appearance should be wrong.'" Such a sentence could never have been written by a man who had any sober conception of the nature of inductive truth. He exhibits, in his own person, the very worst faults of the school in which he has enrolled his name : for he is credulous in the admission of supposed facts, careless in the analysis of physical evidence, and throughout the pages of his book exhibits a more intrepid use of " the circular logic " than is to be met with in the works of any other English writer on a subject of modern science. When convicted of an imperfect enumeration and false arrangement of geological phenomena, it is not enough to tell us in reply that he borrowed his facts from others : if he adopted them without marks of reference or quotation, interpolated them with observations of his own, and drew his own conclusions from them ; then was he, from first to last, as responsible for them to the public, as if they had all been of his own invention. The real question at issue is this ; Do the organic types of the old world, when taken with all the condi- tions under which nature has placed them before our PREFACE TO THE FIFTH EDITION. ll senses, suggest the "theory of development?" My negative reply to this question would be of small value were it not confirmed by the conclusions of those who, during the last thirty years, have been labouring in the field. They tell us that this theory is neither proved, nor made probable, by the phenomena of Geology. On the contrary, they affirm, almost with one voice, that the organic phenomena elaborated in the past his- tory of the earth throw most formidable difficulties in the way of this theory ; even admitting that it is made probable (which it assuredly is not) by a fair induction from the phenomena of living nature. They are a body of hard-working and truth-loving men, who, on points where men may reasonably differ, exhibit many shades of opinion ; but on the present question they appear to speak with one consent. So far from starting with any natural prejudice against this theory, one large section of their body has boldly adopted views which would gain in harmony and consistency by its acceptance. The Huttonians tell us that there is a mechanism within the earth which ex- plains all past changes in the distribution of land and sea, and brings under one natural system of causation all the successive deposits of Geology. Could they point out to us any corresponding material cause that so modified the successive types of animated nature as to bring the organic and mechanical changes of the earth into a good natural co-ordination, their system would then be theoretically perfect. I need not tell J the reader that Sir Charles Lyell has, in this country* Hi PREFACE TO THE FIFTH EDITION. long stood at the head of the Huttonian school, and directed the best efforts of his life to its illustration. He is no timid speculator; yet he rejects the theory of organic development (however gracefully it would lend itself to his general views) because he finds it untrue to nature. Authors who have only glanced at the vestiges of our ancient monsters, and never dared to track so much as one of them to its lurking-place, may, perhaps, tell us that Geologists are in fetters — that they are so embarrassed by a load of facts that they have no power of onward movement — that they have so dimmed their sense in the dark chambers of the earth, that they can hardly endure the light of day. Is there then "no speculation in their eyes?" Are they so cowardly a body that they dare not look beyond the material forms to which they cling ? Their history tells us a far differ- ent story ; and we learn from it that they have too often grasped at consequences beyond the reach of the ground on which they stood ; and that their besetting sin has too often been a rash and intemperate spirit of speculation. Who have been the great leaders in our know- ledge of the laws that govern the material world ? We may reply : the men without exception, who have been great observers themselves, or (at the very least) have learned to appreciate, and embody in their own know- ledge, the labours of the great observers who have gone before them. Every new fact is a spark fitted to kindle in the mind of man some new train of general thought ; so that the best experimenters have ever PREFACE TO THE FIFTH EDITION. liti been the most successful speculators. Theory is not the idol, but the animating soul of advancing know- ledge ; and is then only mischievous when it is set up that it may be worshipped, as if it contained the highest truth ; though it be built on an untried foun- dation, and raised only to the level of our shallow know- ledge. Most of all is it mischievous when it teaches us to turn away from, and, it may be, laugh at the toils of those who are working onward, in good hdpe, along the only road that has ever led to the discovery of material truth. But it may be said that our practical geologists are wanting in that knowledge of natural history and physiology which would make their opinions of decisive value on the theoretical question of development. To such a remark I would oppose the great works of Cuvier, who, after twenty years of labour in deciphering the extinct organic forms of the tertiary rocks of France, came to the conclusion that, in accordance with no known law of nature, could the extinct animals of the tertiary period be regarded as the true progenitors of the nearest analogous forms of animal life in the present world. He did not overlook the theory of develop- ment ; but he denied its truth. In like manner, Agas- siz ; after classifying with consummate skill, and arranging in chronological order more than a thousand extinct species of fossil fishes, derived from all the successive deposits, (commencing with the primary, and ending with the newest tertiary strata,) found that his suc- cessive fossil groups, when so arranged, belonged to no llV PREFACE TO THE FIFTH EDITION. natural ascending scale, and that no one group could be derived, on any known law of generation, from the group which went before it. He, therefore, (whatever may have been his early opinions, of which it would be unfair to judge from a few figurative sentences) re- jected the theory of transmutation and development, as both inadequate and untrue. Owen, again, was a com- parative anatomist of consummate skill before he turned his thoughts to the study of palaeontology. How greatly he has added to our knowledge of the extinct forms of animal life, during the ancient epochs in the history of our globe, need not be stated here : but we know, from his published works, that he also repudiates the theory of development as both inade- quate and untrue. Were the theory true in the living world, geology would oppose to it, at every step, the most formidable difficulties. Take, for example, the chronological ar- rangement of the Reptile Class, so far as we can collect it from the works of Owen; and when so arranged the several Orders, Genera, and Species, cannot be brought into accordance with any conceivable ascending organic scale, whether simple or complicated ; neither are the organic groups so arranged that the species of one epoch can (by any rational law of transmutation) be derived from those of the epoch immediately pre- ceding it. Lastly, I may here refer to the published works and well-known opinions of Professor E. Forbes. He has long been known as an accomplished and philoso- PREFACE TO THE FIFTH EDITION. lv phical naturalist, and as a most unwearied and original investigator into the causes that have modified the dis- tribution of our living organic types. For a few years he has devoted the best efforts of his skill to some of the vital questions of Geology, by labours in the field as well as in the closet : and taking as his guide the great facts that influence the distribution of the living inhabitants of the sea, he has so explained and har- monized the distribution of organic types in the old strata of the earth, as to put them in an intelligible sequence, and to modify the views and language in which the successive phenomena of geology must now be placed before us. It adds a great value to his opinions on the theoretical question of development, that he has personally examined some of the oldest fossil-bearing strata of the geological series, and has seen the order in which the earliest known organic types are arranged by the hand of nature : and assuredly it is among these old deposits, if any where on earth, that the theory of development ought to derive its most unambiguous illustrations. No one can doubt his knowledge of the extreme modifications to which animal life is now ex- posed by a change of physical conditions ; and no one will doubt his boldness as a theorist, or his capacity for the apprehension of the highest form of physical truth. Guided by facts, and the analogies of living nature, he denies the reality of any development whatsoever di- rectly depending upon time. He contends, that no modification of specific types, and no rational theory lvi PREFACE TO THE FIFTH EDITION. of transmutation, can account for such a succession of organic types as is seen in the old strata of the earth. The succession implies nothing less than a creative power bringing the forms of organic life into co-or- dination with the successive physical conditions of the earth. It is not my wish to misrepresent his views, and I believe that I have stated them correctly. In one sense it may be true that time has influenced the development of organic life. For during past epochs, the superficial temperature of the globe, the distribution of land and water, and, in one word, all the great phy- sical causes which modify the distribution of the animal and vegetable types, appear to have undergone a succes- sion of slow, gradual changes : and while we are con- templating these changes, we seem to be ascending step by step to the conditions of the existing period. On this view we might naturally expect the organic types of the old world to exhibit a development towards the forms of living nature : not, however, simply as an effect of time ; but rather as an effect of physical con- ditions brought about gradually during the long lapse of time. And we may remark by the way, that this conclusion is equally true whichever theory we adopt ; whether we affirm that new forms of animal life were produced by physical necessity out of the conditions, or that a creative power adapted these new forms to the gradually changing conditions. As no fauna can exist without some flora to sup- port it, we might conclude, without any further evidence, PREFACE TO THE FIFTH EDITION. Ivil that some species of the vegetable kingdom must have preceded the animal. In like manner, however im- perfect may be our ancient organic records, we might conclude that some of the herbivorous tribes of the mammal class must have preceded the carnivorous. Reasoning of this kind may be admitted without scruple, because it is based on what we know of existing nature ; and the facts of geology, notwithstanding the imperfec- tion of its documents, seem to be m accordance with these sure elements of our knowledge Admitting, however, all which has been stated — that vegetables preceded animals ; and, so far as we have physical evidence bear- ing on the question, — that fishes came into being before reptiles, — reptiles before mammals — and that man is one of the last beings in the order of creation; what does all this prove for the theory of development ? Absolutely nothing ; unless it can be farther shewn that the genera and species of the several Classes have been produced suc- cessively on some natural, ascending scale. And were this proved, (which it is not,) how shall we ascend by any- natural means from Class to Class, unless we can shew some connecting links between them, indicating a slow chronological progression, and a series of "modest steps," whereby one Class may seem to slide into another. Geologists, with one voice, deny that there is any such evidence of progression. They point to continual breaks in the organic scale; and they believe that the highest development of each Class is a fact not dependent upon time, but upon physical conditions. With these remarks I might end this imperfect comment on the theory of s. d. e lviii PREFACE TO THE FIFTH EDITION. development: but physical truth depends not upon authority, and the reader may ask for an enumeration of, at least, some of the facts that have a direct bearing on the question in debate. $ 5. Animal and vegetable Remains of the Primary or Palaeozoic Division. Oldest fossil groups, — Have geologists discovered any denned group of strata marking the period when or- ganic life first began ? We shall never, I think, be able to give any thing better than a doubtful answer to such a question as this. Sir R. I. Murchison thinks he has seen such a group in Scandinavia. It contains Fucoids, rests unconformably on crystalline or metamorphic rocks, and underlies all the other palaeozoic deposits of the country. This discordancy of position proves a want of continuity in the geological sequence, and therefore greatly damages the conclusion, that this group contains the earliest traces of organic life. Better evidence bearing on this question is, perhaps, found in Cumberland ; for in the Skiddaw slates, at an enormous depth below the Silurian groups, are found certain strata with impressions of Fucoids and Grapto- lites. These are, perhaps, the oldest fossil beds of the British Isles ; and below them are other beds of great thickness, not metamorphic, and fit for receiving im- pressions of organic remains, yet without any traces of animal or vegetable life. These lower strata finally pass into a metamorphic condition, and rest on Granite. PREFACE TO THE FIFTH EDITION. Hx No unequivocal traces of this group are found in North Wales, nor is it, I believe, enumerated (as a distinct group or system) in the vast descending series of palaeozoic rocks in North America : and it certainly appears not in any of the well-described portions of the continent of central and western Europe*. Such are our meagre details respecting this supposed protozoic group. Should its place be ever established, we may then expect to find within it the traces of that ancient flora which formed the necessary base of the first germs of animal life. Leaving all hypotheses respecting the most ancient traces of animal or vegetable life, we may next inquire in what form the types of the animal kingdom present themselves in our older Palaeozoic strata. — Commencing with the well-defined upper Silurian strata, and de- * This note is addressed only to geologists, and would be quite out of place were I to introduce any details. In the year 1824 I found one or two places where the Skiddaw slates were stained with carbon, which was probably of vegetable origin : and about two years since J. Ruthven, of Kendal, at my request, re-examined these carbonaceous slates, and found in them the fossils above mentioned. I wish to bring the old dark-coloured slates of the Menai Straits into co- ordination with the Skiddaw slates, but the comparison is defective from the want of fossil evidence. The older palaeozoic sequence in North America is almost identical with that of the British Isles. This opinion was confirmed, in the early part of the present year, by Professor H. D. .Rogers (one of the greatest American authorities), who personally examined the Woodwardian collection, in which a very large series of British palaeo- zoic fossils is arranged stratigraphically. During the past year I examined the border-chain of Scotland that runs from St Abb's Head to the Mull of Galloway. The evidence given by the fossils is not comparable in clear- ness and fulness to that derived from Cumberland, Wales, and the noble sections of North America: but I believe that Mr M'Coy, after very carefully sifting the evidence, has seen enough to prove that the animal sequence in this border-chain, so far as it goes, is almost identical with that given in the great works of the United States Geological Surveyors. e2 lx PREFACE TO THE FIFTH EDITION. scending to the lowest beds containing traces of animal remains, we have in the British Isles a series of de- posits not less than twenty or thirty thousand feet in thickness ; and below them all are beds of great thickness (not crystalline or metamorphic), in which animal remains seem gradually to disappear. This description, with a very slight verbal modification, may also be applied to the older palseozoic deposits of the North of Europe and North America. In some beds of North Wales (at a vast depth below the Upper Silurian strata) are found Lingular, Tellinomyce, and Graptolites ; and a very little higher are Trilobites and Graptolites. These are among the lowest animal remains of the British series; and no Crinoidea and no stony Corals (though admirably fitted for fossil preservation) have been found among them. This little group would hardly deserve a separate notice were it not true that Lingular and Tellinomyce are among the lowest animal fossils of North America. We have seen that the lowest well-marked animal remains discovered in this Island are Graptolites, Telli- nomyw, Lingular, and Trilobites. Among rocks, appa- rently of the same age, in America, are Lingular and other Brachiopoda, followed by Tellinomyw, Orthoceratites, &c. ; but without Trilobites. Should we from this infer that Trilobites came sooner into being in England than in North America ? Certainly not. The evidence offered by our earliest fossil-bearing groups is far too imperfect to bear out any such conclusion. But (says the Author of The Vestiges, Explanations, p. 39,) " The remains of PREFACE TO THE FIFTH EDITION. lxi inferior animals may be found on some lower level, in some as yet unexplored place not far off, so that a time- interval may then appear to allow for progressive de- velopment." True ! Such animals may he hereafter found, whether the theory be true or false. The question at issue is this. Do the organic phenomena of geology suggest the theory of development? We meet the question by a direct jjenial, and an appeal to facts. And it is no reply to tell us, in return, that other facts may hereafter he brought to light so as to modify the nature of the evidence before us. This is the inevitable condition of every advancing science, and is an excellent reason for using much caution in the propagation of any positive dogmatic theory. Leaving the necessarily doubtful evidence respecting the first vestiges of organic life, we have an enormously thick ascending series of deposits, terminating with the Llandeilo and Caradoc groups of the Silurian system. After what has been stated, it would be somewhat incongruous to call the whole series Protozoic, but, pro- visionally, I may call it Cambro-Silurian ; and it includes all the oldest known fossil-bearing groups of North America, and of the north of Europe, under whatsoever names they may hereafter pass. In this vast series we have many portions without fossils, and many wherein they abound. Some of the species ascend from the lowest groups to the highest ; but new species appear to have been gradually added, so that the higher groups are, on the whole, more fossiliferous than the lower. Cephalopods and Crustaceans are seen among the lower Ixii PREFACE TO THE FIFTH EDITION. groups. It is not true that the Crustaceans are all of a humble type. It is not true that the first Cephalopods are small and of a lower type than those which follow them among the higher Palaeozoic groups. In North America some of the very old Cephalopods are almost gigantic. Neither is it true that the fossil species, considered as a whole, conform chronologically to any natural ascending scale of animated nature. Bivalves and univalves are seen together ; and though the former as a general rule, abound more than the latter, yet in certain spots the univalves take the lead. Professor E. Forbes explains this fact by reference to local con- ditions, which produce an analogous distribution among the living inhabitants of deep seas. There is no con- fusion of species. Those which first existed do not slide into those which are superadded, by insensible gradations, either on an ascending or a descending scale ; and many of the species have a great vertical range without the least modification of their spe- cific characters. On the other hand, while on the same geological line, and among deposits of the same date, certain fossils (without changing their specific types) do undergo, like the kindred animals of the present sea, certain variations of form arising out of changes of marine depth, or changes in the nature of the marine bottom. The hard Radiata are rarely, if ever, found in the very lowest groups; but are in great abundance in the upper : and the different Families in this division of the animal kingdom do not appear in any natural order of development. When PREFACE TO THE FIFTH EDITION. lxHi we place them chronologically, as they shew themselves among the ascending deposits, their arrangement is not anatomically natural, and is sometimes on an inverted scale. The same remark applies to the other groups of the animal kingdom. It has been said that the Cephalopod may perhaps be derived by natural trans- mutation from the Pteropod, and that such an arrange- ment would fall in admirably with the theory of deve- lopment. Unfortunately for this theory, the Cephalopod, so far as we have any direct evidence to rest upon, appeared before the Pteropod. Do I then affirm, from such facts as these, that we know the exact order of creation ? I make no such assertion : but I do affirm, and with great confidence, that the organic sequence, brought to light among our oldest palaeozoic strata, does not, when closely examined, suggest the theory of development. Were the theory proved, or made probable, among the phenomena of living nature, it might then, with some show of reason, be taken as our guide while we are endeavouring to unite together the organic fragments of an older world ; and we might endeavour, by help of it, to explain away what we thought anomalous in the order of our oldest fossil types. But to take this theory for granted, while living nature is in most positive antagonism with it ; and, by help of it, to interpolate our oldest geological documents, (sometimes without any pretended evidence, and sometimes in the very teeth of most positive con- flicting evidence,) so as to obtain from them a natural ascending scale in accordance with the scheme of deve- Ixiv PREFACE TO THE FIFTH EDITION. lopment ; and, when we have done all this, then to go back to the phenomena of living nature, and to apply this theory to their interpretation, is as flagrant an instance of bad logic as is to be found in the whole catalogue of human fallacies. The first appearance of fossil fishes may, in the next place, be noticed. In the " Silurian system " we have a description of several species derived from the upper Ludlow rocks, which appear at the base of the Old red sandstone. Collectively, the species belong to a very high organic type, and among them are two Cestracionts. A Cestracion was afterwards found by Mr Brodie in the Wenlock-shale. The extreme rarity of such remains in our oldest fossil-bearing groups, and their entire absence from some of them, is accounted for by Professor E. Forbes, on the supposition (plainly indicated by the whole Fauna of the period), that our oldest Palaeozoic strata were the deposits of a deep ocean ; and probably below the descending limit within which Fishes are found to inhabit our present seas. Be this as it may, all our most ancient fossil Fishes belong to a high organic type ; and the very oldest species, that are well-de- termined, fall naturally into an Order of Fishes which Owen and M tiller place, not at the bottom, but at the top of the whole Class. No man living is infallible, whatever may be his knowledge of nature ; but it is ut- terly incredible that these two great anatomists (with no hypothesis to warp their judgment, and in a classification founded, not upon one character, but upon a combina- PREFACE TO THE FIFTH EDITION. lxV tion of all the united characters which minister to the perfection of an organic type,) should have so egre- giously blundered as to mistake the whole order of precedence, and to place the lowest grade of Fishes at the top of their ascending scale*. Respecting some of the oldest families of fossil fishes, it may be said that our evidence is founded on nothing better than general analogy. JBut how are we to ad- vance one step in the way of physical truth if we shut our eyes to the evidence of analogy ? In the case of the Cestracionts we are not, however, left to mere analogy ; for that family exists in our present seas ; and its anatomy is perhaps as well known as that of any living fishes with which we are most familiar. Anatomical details, are unfit for the nature of this Preface ; but the facts just noticed were too important to be passed over in silence f. They prove that Fishes of the very highest organic type existed during the * Agassiz divides the whole Class of Fishes into four Orders dependent on the exo-skeleton, or the scales. The system is obviously artificial; but is excellently adapted to the classification of fossil fishes, of which (with limited exceptions) the exterior portions only are subjects of examination. His four orders are called Placoids, Ganoids, Ctenoids, and Cycloids. Miiller and Owen have attempted a more natural classification, founded on the collective character of all the nobler organs, whether internal or ex- ternal. In the scheme of Owen (who very nearly follows Miiller), fishes are divided, on an ascending scale, into eleven Orders and six Sub-orders. The highest Order (No. 11 ) includes the whole tribe of Sharks, at the top of which stands the Cestracion — one of our very oldest fossil fishes. The eighth Order includes some of the most remarkable Ganoids of Agassiz, which are characteristic of the Old Red-Sandstone. See Owen's Lectures on Comparative Anatomy, Vol. n., read before the College of Surgeons in 1846. •f For a short abstract of the evidence on which depends the high organic place of the Cestracion, see the Supplement to the Appendix, No. III. 1XV1 PREFACE TO THE FIFTH EDITION. period of some of our old Palaeozoic strata ; and no Fishes of an inferior organic grade have been found below them. Facts more in antagonism with the theory of develop- ment could hardly be expressed in written language. With some of these facts the author of The Ves- tiges was acquainted before he published his Explan- ations, and the more recent editions of his work. And what has he stated in reply ? Absolutely no- thing that has any bearing on the question of classifi- cation. It is true that some living cartilaginous Fishes are very low in the organic scale ; but what has that fact to do with the place of Sharks and Cestracionts ? It is also true that Reptiles, Birds, and Mammals, have hard bones ; for their muscular structure requires the support of a hard skeleton. But who would dream of arranging them on any scale dependent on the percent- age of phosphate of lime, or of any other earthy salt a chemist might extract out of their bones ? A natural classification, to have any meaning, must depend, for its true support, on the collective relations of all the nobler organs — the very principle adopted by M tiller and Owen in their arrangement of the whole Class of Fishes*. * I will endeavour in this note to put before the reader one or two remarkable passages in Owen's Comparative Anatomy of Fishes, " Why, (says this great anatomist, when discussing the true organic place of sharks and other Plagiostomous fishes) the gristly skeleton should be, as it com- monly has been pronounced to be, absolutely inferior to the bony one, is not obvious. The ordinary course of age and decrepitude is associated with a progressive accumulation of earthy and inorganic particles, gradually im- peding and stiffening the movements, and finally stopping the play of the vital machine ; and I know not why a flexible vascular animal substance should be supposed to be raised in the histological scale, because it has PREFACE TO THE FIFTH EDITION. lxvii From a consideration of such facts as have been above stated, Professor E. Forbes concludes, that the become impregnated, and as it were petrified, by the abundant intus-suscep- tion of earthy salts into its areolar tissue. It is perfectly intelligible that this accelerated progress to the inorganic state may be requisite for some special office of such calcified parts in the individual economy; but not, therefore, that it is an absolute elevation of such parts in the series of ani- mal tissues." (p. 146.) Again : M The predaceous sharks are the most active and vigorous of fishes : like birds of prey they soar, as it were, in the upper regions of their atmosphere.... They are the fishes in which the instruments of voluntary motion are the best developed, and in which the cerebellum presents its largest size and most complex structure" (pp. 147 and 188.)..." The gristly skeleton is in prospective harmony with this mode and sphere of life."... "Lightness, toughness, and elasticity, are the qualities of the skeleton most essential to the shark.. ..To have had their entire skeleton consolidated and loaded with earthy matter would have been an incumbrance altogether at variance with the offices which sharks are appointed to fulfil in the economy of the great deep. — Yet there are some who would shut out, by easily com- prehended but quite gratuitous systems of progressive transmutation and self-creative forces, the soul-expanding appreciations of the final purposes of the fecund varieties of animal structures by which we are drawn nearer to the great First Cause. They see nothing more in this modification of the skeleton, which is so beautifully adapted to the exigencies of the high- est of organized fishes (the sharks), than a foreshowing of the cartilaginous condition of the reptilian embryo in an enormous tadpole, arrested at an incomplete stage of typical development. But they have been deceived by the common name given to the Plagiostomous fishes. The animal basis of the shark's skeleton is not cartilage; it is not that consolidated jelly which forms the basis of the bones of the higher vertebrates ; it has more resemblance to mucus ; it requires 1000 times its weight of boiling water for its solution; and it is neither precipitated by infusion of galls, nor yields any gelatine upon evaporation" (p. 147.) In the next paragraph (pp. 147 and 148) he combats the opinion that Ganoid fishes are of a low organic type because of their hard dermal skele- tons. "It is true that in the lowest class of Vertebrata we have the most numerous examples of a hard exterior skeleton. But some anatomists, in their zeal to trace the serial progression of animal forms, seem to have lost sight of all the vertebrate instances of the bony dermal skeleton, except those presented by the Ganoid and Placoid fishes. He must have been sunk to the low conception — that nature had been limited to a certain allowance of the salts of lime in the formation of each animal's skeleton who could affirm, that in the higher Vertebrata the internal articulated skeleton takes all the earthy matter for its consolidation." He then lxviii PREFACE TO THE FIFTH EDITION. oldest truly aquatic and marine fauna, of which we find traces among the monuments of geology, is, when taken collectively, not less noble than the corresponding fauna of our present seas ; and that it offers not the shadow of any ground whereon to build a theory of development. The animals of this ancient fauna were created in ac- cordance with the surrounding physical conditions ; but did not, so far as we have any positive evidence, come into being in any natural organic sequence ; neither have we the semblance of a proof that the several types of the animal kingdom underwent, during the long lapse of ages, any gradual elevation by specific transmutations on any ascending scale: and if all evidence for the theory fail us among the most ancient strata, in vain shall we seek it among the organic phenomena of any more recent epoch*. Three great systems of deposits — the Devonian or Old red sandstone, the Carboniferous, and the Permian — follow the upper Silurian rocks in a regular ascending order, and complete the whole Primary or Palaeozoic division of our fossil-bearing strata. In passing from one system to another, we perceive a great change in the old inhabitants of the sea ; and where these quotes the examples supplied by the Glyptodon and the Armadillos, which have internal skeletons as perfectly ossified as any other mammals ; and concludes — "that the organizing energies, which perfect and strengthen the osseous internal skeleton, do not destroy, or in any degree diminish, the tendency to calcareous depositions on the surface, when the habits of the warm-blooded quadruped require a strong defensive covering." These extracts, combined with the notes in the Supplement to the Appendix, No. III., are, I trust, sufficient for their purpose. * See the Supplement to the Appendix, No, V. PREFACE TO THE FIFTH EDITION. lxix changes are greatest and most sudden, we find (almost without exception) distinct traces of vast physical revo- lutions which must have modified all the conditions bearing on the distribution of the organic types. For example : the upper Silurian rocks are not unusually deposited on the broken edges of the older groups. The Old red sandstone (or Devonian system) followed some of the greatest external movements that ever affected the surface of our globe. Many of its strata are made up of abraded fragments torn from the older rocks and deposited on their broken edges. The physical separa- tion between the Devonian and Carboniferous systems is less complete ; and in some places they seem to pass one into the other by almost insensible gradations. Lastly we have, as a general rule, a great physical break, and a very great organic change, as we pass from the Carboniferous to the Permian groups. What conclusions may we draw from facts like these ? That the great organic changes were brought about, not by gradual transmutation wrought among the spe- cific types during a long lapse of ages, but by altered conditions to which the organic types were successively adapted. Time, considered as a separate element, and independently of changes in the physical conditions bearing on the distribution of organic life, does not appear, so far as we can reason on the evidence, to have produced any specific changes in the old kingdoms of animated nature. I have no wish to describe at any length the three highest systems of the Palaeozoic series enumerated in 1XX PREFACE TO THE FIFTH EDITION. the preceding paragraphs ; but I may be permitted to detain the reader, while alluding, through a few pages, to the Fishes of the Devonian system, . and to the plants of the Carboniferous. Fishes abound in some parts of the Old red sandstone (Devonian sys- tem), and their natural history may be studied in the monograph of Agassiz. In the first four editions of The Vestiges we were told — " that the earliest fishes partook of the character of the lower sub-kingdom, the articulata," — that the Cephalaspis resembled a Trilo- hite — that the Coccosteus had a jaw like the nipper of a lobster, its mouth opening vertically, contrary to the usual mode of the vertebrata — and that such facts compelled us to place these Fishes near the Crustaceans. Now these supposed facts (as remarked in the Edin- burgh Review,) " were only blunders and guesses made by the first observers before any good evidence was before them." And what reply has the Author given (in his Explanations, and his new editions of The Ves- tiges) to the Reviewer's comment ? Nothing but a sneer at a clerical blunder committed in a single sentence where Radiata had been written for Articulata ; and a strenuous reassertion of what is not anatomically true — that the Devonian fishes are low in the organic scale. The whole strength of the Reviewer's comment consists in this statement; — that the fossil Fishes, both of the Devonian and Silurian strata, are of a high organic type, and that some of them exhibit the highest type of their whole Class ; " and that in none of them is there the most remote affinity to Crustaceans or any PREFACE TO THE FIFTH EDITION. lxxi other Artieulata."..." On the contrary, that in many- respects they make an approach to the higher Class of Reptiles — for example, in their dentition, and some of them in their ball -and -socket -jointed vertebrae." (Review, p 35.)* It is in vain to tell us that 30,000 species of fossil Fishes may be hereafter discovered, and so arranged as to fall in with the theory of development. I advance no dogmatic theory ; I simply appeal to facts, and affirm that they do not suggest the theory of development. On the contrary, they oppose to it, in the present condition of our knowledge, an evidence as strong as can be expressed in written words. The whole blame of a rash dogmatic hypothesis rests with my opponent. A theory is worse than nothing if it reflect not back the present condition of our knowledge. If it tell of laws, neither proved nor suggested by the lessons of experiment and observation, it is nothing better than imposture. It is not true, as was rashly stated in former editions of The Vestiges, that our earliest fishes were imperfect and half-abortive forms linked to the lower Class of Artieulata: neither is it true, as con- tinues to be stated by the Author, that the earliest fishes known to geologists were of a humble organic type. Neither is it true, so far as I have any knowledge of the subject, that the fossils, in any part of the world in which the Palaeozoic strata have been well examined, * It is impossible to discuss questions of this kind without details which are ill fitted for this Preface. I have, therefore, thrown into a note some additional facts bearing on the classification of our oldest fossil Fishes. Supplement to the Appendix, No. III. lxxii PREFACE TO THE FIFTH EDITION. follow one another chronologically in any true accord- ance with the hypothetical law of development. Such are the facts on which I join issue with a dogmatic hypothesis. The facts bear out my negative conclu- sion ; they lend not support to the hypothesis, but flatly contradict it. Vegetable Types of the Palaeozoic Period, Sfc. In order to speculate securely about the first beginnings of vegetable life, we ought to know more of the pri- meval condition of the Earth than is, or ever will be, revealed to us by direct physical evidence. Our oldest Palaeozoic strata appear to have been deposited in a deep ocean ; and in such formations we have no right to look for the vegetable spoils of the land, even though we hypothetically admit their existence in as great abundance as during any after period. Again, the first elevated land may have presented nothing but a surface of bare rock utterly unfit to support any of the higher forms of vegetable life ; yet, during the same early period, we can conceive it possible that marine plants may have flourished in abundance, and given support to the first animal in- habitants of the ocean. Through the whole Palaeozoic series we find innu- merable examples of animal remains, entombed in the very spots where they once flourished, and exhibited to us in the very succession in which they once lived at the bottom of the sea, generation after generation. On the contrary, many of our vegetable fossils have been drifted from a distance ; and on this account the PREFACE TO THE FIFTH EDITION. lxxiU successive organic types are far less clearly put before us in the vegetable kingdom than in the animal. In the midst of much doubt and uncertainty, one thing, however, is clear — that some forms of vegetable life must have flourished at the commencement of our very oldest Palaeozoic strata ; for no fauna could possibly exist without them : and, as a matter of fact, we do find, among our oldest known Palaeozoic beds, occasional traces of fucoids and other marine plants ; and the fre- quent absence of all such traces among our very ancient rocks may be accounted for when we remember, that marine plants, from the want of hard ligneous fibre, are but ill fitted for fossil preservation. The oldest groups of our Palaeozoic rocks are of enormous thickness — a fact which in itself explains their consolidation, and partially metamorphic structure. For we have only to bear in mind that they are many thousand feet in thickness — that each bed once formed the bottom of the sea — and that for every hundred feet of descent below the solid surface of the Earth, we have a right to suppose an increment of temper- ature of more than one degree of our common scale. In this way we may, without any appeal to a more direct Plutonic action, account for a great internal ter- restrial heat — sufficient perhaps (when continued for long periods of time, and aided by enormous pressure) to solidify, and entirely mineralize, some of these ancient deposits. Mineral changes of this kind have, no doubt, obliterated innumerable traces of organic life; and I believe every sober-minded geologist will allow that s. d. / Ixxiv PREFACE TO THE FIFTH EDITION. the first commencement either of animal or vegetable types (and more especially of terrestrial plants) is wrapped in impenetrable darkness. I wish not to disturb the reader by ill-timed speculations on the most obscure and difficult points of Geology. What I wish to impress upon him is — that we cannot for a moment reason, with security, on the organic phe- nomena of any period, without taking into account the contemporaneous physical conditions of the Earth's surface. Many of the upper Silurian rocks were formed in a shallow sea ; and during the Devonian period (that followed immediately afterwards) we find traces of very widely-expanded deposits, which appear to have taken place near ancient shores, and in comparatively shallow water. The organic remains belonging to both these periods, whether of mollusks or fishes, bear out this inference. Among the Devonian rocks of the continent of Europe land-plants, nearly agreeing with the Carbonifer- ous type, were drifted abundantly from the neighbouring shores ; and among the deposits of this age in the Rhe- nish provinces I found Coniferous wood, forms nearly allied to Lepidodendra, and Calamites. Some of the Calamites had the external portions so well preserved as to enable Mr M'Coy, in 1847, to determine their dicotyledonous structure*. In the British Isles this evidence is less complete ; yet within them are spots, * This determination has been since verified by Mr Dawes (Geo- logical Journal, May 1848). PREFACE TO THE FIFTH EDITION. lxXV as we have already hinted, where we hardly know how to draw a line between the rocks of the Carbo- niferous and Devonian epochs. Through the Carboniferous period plants were in infi- nite abundance : and from the facts of Geology we learn, that the ancient sea was then studded with great tracts of elevated land surrounded by vast swamps that were covered with forests like those of. a tropical jungle. In the part of the globe now occupied by North America there were, during this period, two great jungles, each of which was spread continuously over an area almost as great as the whole surface of the British Isles. It was not a continued period of repose. Changes of level, both of elevation and depression, destroyed the ancient forests, and buried them under fresh accumulations of drifted matter ; and new forests grew over those which were buried under the new surface of the land. This state of things went on for unnumbered ages, till at length the Carboniferous formations were interrupted by newer changes, and perhaps still greater movements, which brought in the deposits of another system. Judging from the vegetable types, the Carboniferous climate was tropical ; and these types stretched so far north as to pass within the limits of our Arctic seas. Conditions so widely differing from those of existing nature implied, by physical necessity, a widely different flora from that now decorating the earth : and the modi- fying causes were not simply geographical ; for the atmo- sphere must have gradually changed by the submergence of so many great forests and their fixation in successive /2 lxxvi PREFACE TO THE FIFTH EDITION. coal-beds. But was this flora of an imperfect or half- abortive type, as if nature were only in the agonies of a struggle towards something higher and better? No such marks of imperfection are stamped on it ; and we believe it to have been a perfect flora, in accordance with the conditions of its time. The several species, so far as we can reason on them through the analogies of living nature, shew no marks of imperfection : and many of the species and genera, which flourished in infinite abundance during the Carboniferous epoch, and never lived afterwards, are of strange but most complicated organic structure ; so that some of our best botanists were long in doubt whether to place them among the monocotyledonous or the dicotyledonous divisions of their flora. If they be monocotyledonous, then are they among the very highest types that ever existed in that division of the vegetable world. Again, we derive not, from this ancient flora, any proof that monocotyledonous plants preceded the dico- tyledonous ; for fragments of pine-trees are found among some of the older Carboniferous rocks. Still less have we any proof that monocotyledonous plants were, in pro- gress of ages, transformed into dicotyledonous. On the contrary, we believe, on good analogy, that the two great divisions of the vegetable world, after they were called into being, went on, side by side, on two separate organic lines ; the numerical proportions between the two depending, during all epochs, upon physical con- ditions. In some of our present tropical forests we have a great preponderance of monocotyledonous trees ; PREFACE TO THE FIFTH EDITION. lxXVH while, in climates like our own, all the forest-trees are dicotyledonous. Should we then conclude that the pre- sent tropical forests are both of a lower organic type, and of an older date, than those of our own climate ? We know that such a conclusion would be false. Why then should we venture to affirm a similar conclusion while we are reasoning on the Carboniferous flora f Analogy, our best guide while we are deprived of any other* rather tells us, that the numerical proportions among the organic types of the Carboniferous flora depended not on the time that had elapsed after the several species had come into being, but on the physical con- ditions under which they flourished. But great injustice is sometimes done to the rank of the Carboniferous flora while we are comparing it with that of the living world. The ancient flora is but a mere fragment of an organic series produced during one almost unvaried set of conditions; while the present flora consists of species, counted by tens of thousands, and derived from every condition of climate, from the arctic to the tropical, compatible with vegetable life. No wonder, then, that the present flora should seem to lord it over the older, and give an appearance of inferi- ority to the ancient types, which belongs not to their collective nature because they are ancient ; but depends, more probably, on the conditions under which they grew, and on the mutilated state in which we find their scattered fragments. Conclusion. — In this section of the Preface I have endeavoured to shew in what manner geologists try to lxxviil PREFACE TO THE FIFTH EDITION. clear their way among the broken fragments of a for- mer world. They examine these fragments one by one, and learn to arrange them, in the exact order of their history : and taking the analogies of living nature as their clew through the dark labyrinths of the earth, they do their best to interpret the past by help of the present — what is dark by what is light — what is un- known by what is known. They are not anxious to form any theory : and if as a matter of speculation they do construct a theory, they profess to base it on allowed facts, and not on vague assumptions, which the progress of knowledge may prove to be untrue ; and at every mo- ment of their progress they are ready either to modify it, or to abandon it altogether, as new phenomena rise up before them. First Forms of Vegetable and Animal Life as described in " The Vestiges," &c. Let us now cast an eye over the shorter method by which the Author of The Vestiges professes to give colour to his hypothesis, and to bring the successive organic types, whether animal or vegetable, into a seem- ing accordance with it. I wish not to misrepresent him, and I should gain nothing by the attempt. First, he supposes that the humble vegetable types of the sea were the oldest of their Class. This conclu- sion may be true ; but, as we have seen, it rests not on good direct evidence. Secondly, he supposes the vegetable types to have undergone a gradual transmutation, during a long lapse PREFACE TO THE FIFTH EDITION. lxxix of ages — to have come out from the sea, and to have been spread over the dry land under modified organic forms. Of this derivation of our earliest land-plants we have no proof. Its assumption is nothing better than a begging of the whole question in debate ; and it is both gratuit- ous and unnecessary to the hypothesis of development. It certainly accords not with any phenomena of our liv- ing flora. We have innumerable opportunities on our own coasts of testing the truth of this rash hypothesis. We find marine and land-plants growing side by side. In a few years the sea gains upon the land, and marine plants now grow where only land-plants grew before. In other cases the sea retires, and we now find land- plants where before we only found either marsh-plants, or those that were purely marine. But who, that is in his senses, refers such changes to specific transmutations? Or who that has seen marine and land-plants struggling side by side, as they have done for centuries, under con- ditions unfavourable to both, will dare to tell us that one set gradually gets the mastery by specifically trans- forming and naturalizing the other*? Thirdly, he assumes that monocotyledonous plants passed by gradual transmutation into dicotyledonous — that the Carboniferous flora was of an humble and im- perfect type — and that its antiquity and inferiority is proved by the excess of its monocotyledonous types. Of this part of the scheme we may affirm that it is de- fective in the statement of fact and erroneous in infer- ence ; and it derives no probability from the succession * See Supplement to the Appendix No. IV. and No. VI. ]XXX PREFACE TO THE FIFTH EDITION. of organic types in our older strata. The succession of vegetable types is, however, so broken and imperfect as to be of comparatively small value to the argument. Most of our Palaeozoic rocks are marine ; and among them, as before stated, we have no right to look for, nor do we find, any thing like a continued sequence of such plants as might have grown contemporaneously on the land. If there be any show of probability in the application of our Author's scheme to the Palaeozoic epochs, it must be derived analogically from some dif- ferent source. The theory is not shadowed forth among the vegetable phenomena of the Secondary or Tertiary rocks ; and I know not of any source of good evidence, bearing upon the question, beyond that which flows from the vegetable kingdoms of the present world. Let us next glance at our Author's method of in- terpreting the history of the animal kingdom, from succession of organic types among our oldest Palaeozoic strata. In the first four editions of The Vestiges he stated, without any reserve, that the animals of the old world appeared, among the successive strata, in a natu- ral ascending organic scale ; and what he asserted then he now only insinuates. " The first animals, (as he tells us, Vestiges, 6th Ed. p. 52), we are called on to notice, are Polyparia" — the creatures producing coral-reefs. Next he notices Graptolites; and then Crindidia. Now Graptolites do appear at the base of our known organic series ; but the Polyparia which produce coral- reefs do not ; neither do Crindidia. When he after- wards adds, that these latter animals may hereafter PREFACE TO THE FIFTH EDITION. Ixxxi be discovered in the place he has given them, he writes in the language of theory, and not of chro- nological history. — " Of the Articulata we have,' 1 (he says, p. 54), "first a few examples of its lowest class, the Anellides or sea- worms ;" and he quotes the well- known case of the Lampeter species. These Lampeter Anellides are undoubtedly of great antiquity ; but they belong not to a low type of Anellides, but to the high- est type of their class ; and tnere are found in Wales other creatures of far higher organization, such as Trilo- bites, and Cephalopods, several thousand feet below them*. He adds, " that Trilobites stand low in the Crus- tacea; nor were there any higher animals of the order (such as crabs and lobsters) yet in existence." I have never seen Crabs among the fossils of the great Cambro-Silurian groups ; but the gentlemen of the Government Survey tell me that they have. He then notices the Brachiopoda, Pteropoda, Gas- teropoda, and Cephalopoda, in their natural order on an organic scale ; and he reasons on this order as if it were historically true. A Brachiopod (Linguld) is one of our oldest known Mollusks ; but it occurs, as stated above, along with the Tellinomya, which is a Lamellibranch ; and the Cephalopods are found quite as * In the frontier chain of Scotland I found sixteen species of Grapto- lites. Four of them are new ; the others (with one exception) are described by Hall (Palaeontology of New York) from the Utica slate. These Grap- tolites of Scotland are associated with Anellides ; and they are, beyond doubt, of great antiquity, and perhaps not far from the parallel of the Lampeter fossils. They are, I think, not so old as the Graptolites found in the Skiddaw slate. (Supra, note p. 59.) The species have been care- fully determined by Mr M'Coy ; and the specimens in the Cambridge Museum prove, beyond any doubt, that Graptolites belong to the Order of Hydroida, as was first asserted by Neilson. lxxxii PREFACE TO THE FIFTH EDITION. low as, and I believe much lower than, the Pteropods. — Lastly, he tells us " that during the lower Silurian era, there was as yet no fish nor any other kind of vertebrated animal, nor any creature which lived on dry land."... Giving him all the benefit of these asser- tions, (which it would be very hard to establish on mere negative evidence), I reply, that we have no right to expect land-animals, or even fishes, among the fossils of a very deep sea : and that fishes of the vert/ highest organic type are found near the upper limit of our older Palaeozoic groups. When facts are told histo- rically, what becomes of the theory of development ? Be it true or false, it is not suggested by Geology ; and we can see no signs " of the comparative newness of life"" among these most ancient fossils *. Passing on to the Devonian Fishes (Placoids and Ganoids), he tells us, " that they are manifestly inferior to the two other Orders — Ctenoids and Cycloids — which afterwards came into existence" (p. 64). What is so manifest to the Author is not true to nature. The reader has some of the evidence before himf. The very highest families of Sharks, and Ganoids of the noblest type and close upon the Class of Reptiles, are found among the Devonian Fishes. — It is not true that all these Ganoids have their backbones imper- fectly represented by a continuous cartilaginous chord. Some of them at least (and perhaps most of them) had as true vertebral joints as any living Fishes ; and they do not all conform to the embryonic type of * Supplement to the Appendix, No. V. -f Note supra p. 64, and Supplement to the Appendix, No 111. PREFACE TO THE FIFTH EDITION. lxxxitt hard-boned Fishes. It is not true that in all the Fishes, without exception, which have been found in the strata of the Palaeozoic period, the caudal fin is truly heterocer- cal, (p. 66). And were this true, it would only prove the worthlessness of any attempt to arrange the organic rank of Placoids and Ganoids by an appeal to the embryonic tails of the Fishes of another Order *. Finally, we are taught (p. J)9) — "that, overlook- ing possible exceptions of a very dubious and narrow kind, we meet with no traces of land-plants" during the Devonian period. — I must state in reply, that the ex- ceptions are neither dubious nor small in number — that land-plants are found among the Devonian deposits of our Island, — and that among the rocks of that age in the Rhenish provinces, such plants are numerous. If the reader believe the previous statements, and I wish not to deceive him, he will at once see how widely different is the history given in the unerring book of nature from the fabulous narrative in some written records of creation. Leaving what we may call the Author's historical narrative, let us next examine his more general views on the origin of animated nature. Bearing on this sub- * I know that my opinion is of little value, but I have often wished certain strange monsters, such as the Pterichthys and Coccosteus, to be taken from the other Ganoids, and placed in some natural Order by them- selves. This has been done (and in no compliancy with any suggestion of mine) by Mr M'Coy, who arranges these and kindred Genera in his Order Placodermata(An. Nat. Hist. 1846.) Some of them, at least, have as per- fect vertebrae as any fishes : and as we find the noblest Ganoids running towards the Lacertian type ; so these singular fishes, cased in an exo- skeleton of great osseous plates, may perhaps be found to range toward the type of the Chelonians. Be this as it may, they certainly link not on, as was at first conjectured, to the Articulata. lxxxiv PREFACE TO THE FIFTH EDITION. ject, I will first quote a very characteristic passage from his Explanations (p. 151): "In an arbitrary system," (meaning by these words any system that does not imply the theory of development), "we have scarcely any reason to expect mammals after reptiles ; yet in this order they come. The Edinburgh Re- viewer speaks of animals as coming in adaptation to conditions; but this is only true in a limited sense. The groves which formed the coal-beds might have been a fitting habitation for reptiles, birds, and mam- mals, as such groves are at the present day; yet we see none of the last of these classes, and hardly any trace of the two first, in that period of the earth. Where the iguanodon lived, the elephant might have lived : but there was no elephant at that time. The sea of the Lower Silurian era was capable of support- ing fish ; but no fish existed. It hence forcibly appears that the theatres of life must have lain unserviceable, or in the possession of a tenantry inferior to what might have enjoyed them, for many ages. There surely would have been no such waste allowed in a System where Omni- potence was working upon a plan of minute attention to specialities." I have not time to point out the bad logic, the unwarranted assertions, and the positive mis- takes of this passage : but I may return to the con- cluding sentence, which is mischievous and irreverent. In the same spirit he writes in the last edition of The Vestiges, (p. 159 — 168): but my limits compel me to abridge the extracts from this work. " Organic beings came not at once, as they might have been expected to do if produced by some special act on part PREFACE TO THE FIFTH EDITION. lxXXV of the Deity .... They came in a long succession in the order of progressive organization. 1 ' What might have been expected I profess not to tell : but if we are to trust our senses they did not follow in such an order as to suggest a natural derivation, one from another. Again, M At the beginning of geological investigation it was thought that some intermediate external con- ditions ruled the appearance- of particular classes of animals at particular times .... But it is now seen that the progress of the animal world was in its main features independent of such circumstances." We may ask in reply, By whom has this been seen? Not by the geologists who are now doing the best service in the field. They, every day, see more and more proofs of the modifying influence of conditions ; and some of them deny that there are any features of animal progress which are independent of conditions. He then tells us, " It was a dream of the dawn of true geology that fresh creations of animals were connected with great physical revolutions of the surface .... but this idea is likewise passing away In short, it is becoming more and more clear that organic progress depended not by any means wholly or immediately upon external circumstances, but in a great part upon time."" (p. 161.) What the Author means by the "dawn of geology," I profess not well to understand: but I affirm it as certain truth, that the greatest changes of organic types among our strata are connected with physical revolutions ; and that it is by a change of con- ditions, and not, properly speaking, by a lapse of time, lxXXVi PREFACE TO THE FIFTH EDITION. that we can rationally interpret the organic sequence of the old world. *' All this," the Author adds, " looks unlike either special working or special willing on the part of the Creator." Having given us a history of nature, not warranted by fact, he then tells us this history is inconsistent with the idea of any exercise of a Provi- dential and Creative will. I shall return to this last inference in another part of the Preface : my present business is with our Author's history, and the physical theory he pretends to found upon it. How he is to reconcile all the previous extracts to the expression of his more general views, I profess not to understand. Thus, he tells us, (p. 154), "that life, as it were, pressed in whenever and wherever there were suitable conditions : " yet within a few pages he tells us, as we have seen, that the phenomena of orga- nic development "depended comparatively little upon conditions, but in a great part upon time." Again, he teaches us, " that the oolitic continents, where only rep- tiles roamed, could equally have supported mammalia .... yet mammalia came not." (p. 161.) Now had these unqualified statements been true, Mammals ought, on his own principles, to have been developed in great abundance before the end of the Oolitic and Cretaceous periods : for Mammals did come into being during the deposit of the Stonesfield slate, not far from the base of the great Oolitic group ; and this at least is true, that not so much as one fragment of a terrestrial Mammal's bone has yet been discovered in the higher parts of the Oolites, the Wealden beds, or the Chalk. PREFACE TO THE FIFTH EDITION. lxXXVH But after the period of the Chalk, and in the lowest division of the great Tertiary series, terrestrial Mammals appeared again ; and in a comparatively short lapse of time, so far as we can judge from the evidence, they multiplied in Genera and Species, and flourished in great abundance. Such facts seem to prove (whether the transmutation scheme be true or false), that con- ditions, far more than time, have, in all ages influenced the progression of animal types. I will give the reader another example of the Author's logical skill ; and it exhibits one of those cases of plausible, verbal sophistry, which have so often cheated men, ill acquainted with facts, into unwarrant- able conclusions. After informing us "that (while we are examining the successive deposits of geology) the total mass of animal creation puts on, more and more, the appearance which it now bears," — he proceeds to ask us, u if this does not seem to imply that the present system of things is essentially connected with the past ; in which case, if the present is a natural system, we have an additional proof that the past was a na- tural system also?" (p. 162.) No one has ever denied that the whole geological sequence presents a series of true historical monuments. We believe that the successive deposits, of all periods, were formed by natural means ; and that the animals entombed within them performed all the functions of life as animals perform them now, and that they flourished under conditions which were in fit accordance with their organic structure. But the words, natural system, lxXXViii PREFACE TO THE FIFTH EDITION. have two very different meanings in the previous ex- tract. In the first instance, they only mean that natural sequence of organic life which is going on before our eyes from one generation to another : but in their second use they are meant to imply that the animal types of one geological period produced (in the way of natural generation) the new animal types of the next period ; and so on, in a regularly ascending order, till we reach the present system of nature, in which species do not change. In other words, that mollusks pro- duced fishes, that fishes generated reptiles, that rep- tiles generated birds, that birds became mammals, and that monkeys (the highest type of old mammals) be- came the natural parents of the human family. By a slippery use of the words, natural system, the Author imposes on the careless reader, and perhaps imposes on himself. If this pedigree be true, we may well ask, as Cuvier did nearly forty years since, pourquoi les entrailles de la terre n'ont-elles point conserve les monu- mens d'une genealogie si curieuse f He found no traces of it among the rocks above the Chalk ; and since his time geologists have spared no pains to discover and interpret the oldest records of creation ; and, so far as they have read them, they find not one leaf of this monstrous genealogy ; nor is its possible existence sug- gested by any hint which they have derived from their ancient documents. Here I conclude my remarks on the organic series of the Palaeozoic rocks, so far as it bears on the theory of development. PREFACE TO THE FIFTH EDITION. lxxxix fi 6. Fossils of the Secondary Division, fyc. While we ascend from the Palseozoic (or Primary) to the lowest Secondary groups, we continually meet with proofs of great internal movements and altered physical conditions. Beds piled on one another, and sometimes in a discordant position — great heaps of conglomerate — abraded fragments ground down into beds of sandstone, marl, and mud, generally of a deep red colour — these are the physical monuments of the period ; and they may be traced through the European Continent, and the British Isles, and (with some change of mineral type) through wide tracts of North America. Volcanic action on a vast scale may, perhaps, have supplied the materials whereby the sea in many places became of a deep red colour ; and whereby the older types of marine organic life were, through many re- gions, utterly destroyed. Trees, however, flourished during this time upon the land, and were sometimes washed down into the sea and saved from entire de- struction ; for we, here and there, find their petrified trunks among these red deposits. Tortoises, gigantic Batrachians, and other strange Reptiles, were, during this tumultuous period, crawling near the margin of the sea ; for we sometimes (though rarely) find their bones, but more frequently the marks of their foot- steps, on strata deposited at this period between the high- and low-water level. The whole series of the deposits above noticed is called Trias, and has been divided, by the geologists s. d. g XC PREFACE TO THE FIFTH EDITION. of Germany, into three groups — the Bunter-sandstein, the Muschel-kalk, and the Keuper — which are followed in a regular ascending order by the Oolitic series and the Chalk. The middle group of the three {Muschel- Jcalh) abounds in fossils; and it gives us one good marine fauna between the Palaeozoic rocks and the Lias which forms the base of the Oolites. Unfortunately this middle group is not found in the British Isles. Its absence may, I think, be ex- plained by the fact, that all those parts of the sea, out of which in after times rose up our Island, were turbid and deeply tinged by the continued agency of volcanic fires : and that great changes of level did take place at this time, is proved by the fact, that the upper part of the New red-sandstone of England is not unusu- ally deposited on the broken edges of the upheaved red beds which we find below them. Be this explanation right or wrong, the sea was for a time less turbid in that part of the world where we now find central Ger- many and an adjacent part of France, and the con- temporaneous deposits were of a more ordinary colour : and in conformity with these conditions there flourished the noble marine fauna of the Muschel-lcalJc. But this fauna was in its turn destroyed — the sea again became red and turbid ; and the Keuper of France and Ger- many became physically identical with those beds of our New red-sandstone which form the top of the whole series here described, and are packed immediately under the Lias beds and Oolites. The fossils of the Muscliel-kalk give us therefore PREFACE TO THE FIFTH EDITION. XC1 the first distinct organic step among the marine deposits, after we leave the Palaeozoic rocks, and begin our ascent among those of the great Secondary division. What then are the organic types we find in this fauna of the Muschel-kalk ? I will answer this question in the words of the Edinburgh Reviewer : " We do not here find so much as one single species with which we are familiar in the Palaeozoic series; All the older Families and Orders have disappeared, and even the Saurians differ in Order from those of the preceding epoch. It is not too much to say that nature has destroyed all her old moulds of workmanship, and begun a new work on a different plan. Yet is there (in those parts of the world where we find the Muschel-kalk) no break or interruption in the regular sequence of deposits. We accept these facts of nature as we find them. The physical conditions of the earth were changed, and Creative Wisdom called into new being organic struc- tures to suit the change. With this we are content ; and we defy any man living, whatever may be his knowledge, to prove that in these steps of the great ascending series 'the stages of advance were very small' — 'only a new stage in the progress of gestation, an event simply natural ' — ' a development from species to species/ — ' phenomena of a simple and a modest cha- racter ! ' Assertions more opposed to the works of ancient nature were never before recorded in the writ- ten language of a gratuitous hypothesis*." * See Edinburgh Review, No. clxv. p. 52; and Vestiges, &c. 3rd Edition, p. 231. 9% XC11 PREFACE TO THE FIFTH EDITION. I entreat the academic readers, to whom the fol- lowing Discourse is more immediately addressed, to examine for themselves, in the cabinets of the Wood- wardian Museum, (thanks to Mr M'Coy, now in excellent arrangement,) the organic sequence of the Primary and Secondary series ; and they will there see good evidence for these strong affirmations of the Re- viewer; to which, indeed, nothing has been opposed but vague hypotheses. It may perhaps be urged, that the intervening and connecting types might have ex- isted in some remote seas from which they passed by migration to that part of the ocean out of which central Germany was elevated in after times : but we have neither positive facts nor probable presumption for the hypothesis : for there is neither gradation nor mingling of Species, so far as we know, between the newer Palaeozoic types and those of the Muschel-Jcalk : nor are there in those parts of Germany and France where we find the Muschel-Jcalk any indications of break or interruption among the deposits which might suggest to the mind a notion that some great links of the organic chain have been lost. Again, certain organic families (for example Orthoceratites) are found, in a few rare instances (for example, among the Alps), straggling beyond their ordinary bounds into the lower parts of the Secondary groups : but they shew no deviation from their normal structure, nor any passage towards the known Secondary types of Brachiopoda. They offer no argument for the theory of development: but they do seem to shew, that in all cases, both the beginning PREFACE TO THE FIFTH EDITION. XC111 and the end of organic families depended rather upon physical conditions than upon time*. Lastly, it might perhaps be urged, that allowing nature to have broken her ancient moulds of workman- ship when she commenced with the fauna of the Mus- chel-kalk, we have a right to suppose that she began her work afresh, and completed it in the way of natural development. If so, we ought jto see some traces of this mode of working among the successive beds ; — but we find no such trace ; for the fossils of the group are not produced, one above the other, in the approximate order of any conceivable organic scale. Well may we again (in the words of Cuvier) ask those who affirm the theory of development, " Pourquoi les entrailles de la terre rCont elles point conserve les monumens