IMAGE EVALUATION TEST TARGET (MT-3) 1.0 I.I IIIM 1125 IIIIM :iiti6 12.2 2.0 1.8 1.25 1.4 1.6 ^ 6" - ► Va ^ /} om( e". el /a o> -'N y ^^ 4 Photographic Sciences Corporation 23 WEST MAIN STREET WEBSTER, NY. 14S80 (716) 872-4503 Q- CIHM/ICMH Microfiche Series. CIHIVI/ICMH Collection de microfiches. Canadian Institute for Historical Microreproductions Institut Canadian de microreproductions historiques 1980 Technical and Bibliographic Notes/Notes techniques et bibliographiques The Institute has attempted to obtain the best original copy available for filming. Features of this copy which may be bibliographically unique, which may alter any of the images in the reproduction, or which may significantly change the usual method of filming, are checked below. L'Institut a microfilm^ le meilleur exemplaire qu'il lui a 6t6 possible de se procurer. Les details de cet exemplaire qui sont peut-dtre uniques du point de vue bibliographique, qui peuvent modifier une image reproduite, ou qui peuvent exiger une modification dans la mdthode normale de filmage sont indiquds ci-dessous. n n D D n D D D Coloured covers/ Couverture de couleur Covers damaged/ Couverture endommagde Covers restored and/or laminated/ Couverture restaurie et/ou pellicul6e Cover title missing/ Le titre de couverture manque Coloured maps/ Cartes gdographiques en couleur Coloured ink (i.e. other than blue or black)/ Encre de couleur (i.e. autre que bleue ou noire) Coloured plates and/or illustrations/ Planches et/ou illustrations en couleur Bound with other material/ Relid avec d'autres documents Tight binding may cause shadows or distortion along interior margin/ La reliure serree peut causer de I'ombre ou de la distortion le long de la marge intdrieure Blank leaves added during restoration may appear within the text. Whenever possible, these have been omitted from filming/ II se peut que certaines pages blanches ajout^es lors d'une restauration apparaissent dans le texte, mais, lorsque cela 6tait possible, ces pages n'ont pas 6t6 film^es. n >/ n Coloured pages/ Pages de couleur Pages damaged/ Pages endommagdes Pages restored and/or laminated/ Pages restaurdes et/ou pellicul^es Pages discoloured, stained or foxed/ Pages d6color6es, tacheti^es ou piqu^es Pages detached/ Pages d^tachdes r~^ Showthrough/ I I Transparence I I Quality of print varies/ D D Quality in6gale de I'impression Includes supplementary material/ Comprend du materiel supplementaire Only edition available/ Seule Edition disponible Pages wholly or partially obscured by errata slips, tissues, etc., have been refilmed to ensure the best possible image/ Les pages totalement ou partiellement obscurcies par un feuillet d'errata, une pelure, etc., ont 6t^ film^es d nouveau de fapon d obtenir la meilleure image possible. D Additional comments:/ Commentaires suppl6mentaires: This item is filmed at the reduction ratio checked below/ Ce document est film^ au taux de reduction indiqud ci-dessous. 10X 14X 18X 22X 26X SOX v/ 12X 16X 20X 24X 28X 32X lils lu Jifier ine age The copy filmed here has been reproduced thanks to the generosity of: The Nova Scotia Legislative Library The images appearing here are the best quality possible considering the condition and legibility of the original copy and in keeping with the filming contract specifications. L'exemplaire film6 fut reproduit grAce A la g6n6rosit6 de: The Nova Scotia Legislative Library Les images suivantes ont 6ti reproduites avec le plus grand soin, compte tenu de la condition et de la nettet6 de l'exemplaire film6, et en conformity avec les conditions du contrat de filmage. Original copies in printed paper covers are filmed beginning with the front cover and ending on the last page with a printed or illustrated impres- sion, or the back cover when appropriate. All other original copies are filmed beginning on the first page with a printed or illustrated impres- sion, and ending on the last page with a printed or illustrated impression. Les exemplaires originaux dont la couverture en papier est imprim6e sont filmds en commenpant par le premier plat et en terminant soit par la dernidre page qui comporte une empreinte d'impression ou d'illustration, b par le second plat, selon le cas. Tous les autres exemplaires originaux sont filmds en commenpant par la premidre page qui comporte une empreinte d'impression ou d'illustration et en terminant par la dernidre page qui comporte une telle empreinte. The last recorded frame on each microfiche shall contain the symbol — ^^ (meaning "CON- TINUED "), or the symbol V (meaning "END "), whichever applies. Un des symboles suivants apparaitra sur la dernidre image de cheque microfiche, selon le cas: le symbole — ^ signifie "A SUIVRE", le symbole V signifie "FIN". Maps, plates, charts, etc., may be filmed at different reduction ratios. Those too large to be entirely included in one exposure are filmed beginning in the upper left hand corner, left to right and top to bottom, as many frames as required. The following diagrams illustrate the method: Les cartes, planches, tableaux, etc., peuvent dtre film6s d des taux de reduction diffdrents. Lorsque le document est trop grand pour dtre reproduit en un seul clich6, il est filrr.i i partir de Tangle sup6rieur gauche, de gauche d droite, et de haut en bas, en prenant le nombre d'images nicessaire. Les diagrammes suivants illustrent la mdthode. ata siure. 3 I2X 1 2 3 1 2 3 4 5 6 ■^■' m-'" \ *-" 'b1>^<^ ^ 5" c/x i\ (From the Canadian Naturalist V^dl.'j^ No. 4.) NOTE ON RECENT CONtROVEKSIES RESPECTING •»v«i» EOZOON CANADENSE. Bv Princii'al Dawson, LL.D., F.R.S., Ac. In ^a' recent article, published in the American Jourruil 0/ iSai^ce, I have rem;»rked that ^^^Eozoon Canadeiise hnii, since the first anoounocment of its discovery by Logan in 1859, attracted njuch attentioD, and has befen very thoroughly investigated and disoasseii,- and at present its organic character is generally admitted; 8tRt its claims «re e^er and anon disputed, and as fast as one of^enent is disposed of, another appears. This is in great part due tc the fact that so few scietvtific men are in a position fully to apprecistte the evidence respecting it. Geologists and mineralogists look upeii it. with suspicion, partly on account of the great age and crystul- line structure of the rocks in which it occurs, partly because it is associated with the protean and disputed mineral Serpentine, which some regard as eruptive, some as mctamorphic, some as psoudomorphic, while few have had enough experience to enable them to understand the difference between those serpentines which occur in limestones, and in such relations as to prove their contemporaneous deposition, and those which may have resulted from the hydration of olivine or similar changes. Only a few also have learned that Eozoon is only sometimes associated with serpentine, but that it occurs also mineralized with loganite, pyroxene, dolomite, or even earthy limestone, though the .«ierpen- tinous specimens have attracted the most attention, owing to their beauty and abundance in certain localities. The biologiuts on the other hand, even those who are somewhat familiar with foramiuiferal organisms, are little acquainted with the appearance ©f these when mineralized with silicates, traversed with iQiRiite fnineral veins, faulted, crushed and partly defaced, as is the case with most specimens of Eozoon. Nor are they willing to admit the possibility that these ancient organisms may have presented n more generalized and less definite structure than their modern suoceasors. Worse, perhaps, than all these, is the circumstance ihat dealers and injudicious amateurs have' intervened, and have oireulated specimens of Eozoon, in which the structure is too imperfectly preserved to admit of its recognition, or even Diere »-«ife«H :-fr- 3 fragmeDts of serpentindus limestone, without any structure what- ever. I have seen in the collections of dealers and even in public museums, specimens labelled " Eozoon Canadtnse,'' which have as little claim to that designation as a chip of limestone has to be called a coral or a crinoid," ='• These statements v^ere called forth by the appearance of a learned and well illustrated paper, disputing the animal nature of Eozoon, by Prof Karl Moebius of Kiel, and in which, on the evidence of several specimens given to him by Dr. C-irpeiiter and myself, he assumes that he has " investigated more closely and described more minutely " than any other naturalist, its forms and structures, and that by his labours Eozoon has been '* suc- cessfully eliminated from the domain of organic bodies." feince the appearance of this memoir, and of my criticism upon it, Moebius has published in the same Journal a reply, which has appended to it a note by the principal editor, closing the contro- versy in so far as that Journal is concerned, by stating that the editor had pledged himself that no rejoinder would be permitted. This, of course, excludes ti;e advocates of tlu; animal nature of Eozoon from any farther argument, in so far as ilie principal organ of scientific opinion in th(^ United States is concerned; and it is partly for this reason that I appear at present in the attitude of a defender of Eorjtou on its own soil, instead of, as heretofore, carrying the war into the enemy's country. Still later than this reply of Moebius, are two additional papers of still more remarkable ciiaracter. For. while Moebius is content to take up a purely nesrative position, these undertake to account for the structures of Eozoon by other causes than that of animal growth, and by causes altogether inconsistent with one another. The first of these is an abstract of a memoir •' On the origin of the mineral, structural and chemical characters of :^ Ophites and related rocks." presented to the Royal Society of London by Professors King and Rowney. The second is a quarto pamphlet of 96 pages with 30 plates, by Dr. Otto Hahn, entitled " Die Urzelle,,' the " Primordial cell." I confess I do not regard either of these papers as of any scientific value, in so far as Eozoon is concerned, but as they are at least bold and confident in their tone, and emanate from quarters which may be supposed to give them some little influ- * Amor. .lour, of Hitience. March. 1879. l^^J^ H , 3 ence, I think it well to notice thorn along with the reply of Prof. Moebius. Moebius has thought proper to take advantage of the security guaranteed to him by the Editor of the American Journal, to reply to my courteous and somewhat forbearing criticism, in a manner which relieves me from any obligation to be reticent as to his errors ;md omissions. I shall, however, contint? myself to those points in his rejoinder which seem most important in the interest of scientific truth. 1. With reference to the geological and mineral relations of Eozoon, I cannot acquit Moebius of a certain amount of inex- cusable ignomnce. More especially, he treats the structures as if they consisted merely of serpentine and c.wlcite, and neglects to consider those specimens which, if more rare, are not less impor- tant, in which the fossil has been mineralised by Loganite, Pyroxene and Dolomite. If he had not specimens of these, he should have procured them before publishing on the subject. He neglects also to consider the broken fragments of Eozoon scattered thiough the limestones, and the multitudes o^ Archceo- spherina' lying in the layers of deposit. Nor can I find that he has any clear idea how the structures of Eozoon could have been produced otherwise than by living organisms. Still farther, he mnkes requirements ;is to the state of preservation of the proper wall and canal system which would be unfair even in the case of Tertiary or Cretaceous Foruminifcra injected with Glauconite, how much more in the case of a very ancient fossil contained in rocks which have been subjected to great mechanical and chemi- cal alteration. 2. In his reply he reiterates the statement that Eozoon is so different from existing Foraminiferd. tliat, if this is a fossil, we must divide all organic bodies in "I. Organic bodies with protoplasmic nature (all plants and animals) ; and 2. Organic bodies of Eozoonic nature (AW^o/t, Dawson)," Without refer- ring to the somewhat offensive way in which this is stated, I need only say that Dr. Carpenter has well replied that the structures of Eozoon are in no respect more different from those of modern Foraminifera than those ol' many other old fossils are from their modern representatives. All palaeontologists know, for example, that while we cannot doubt that Receptuculites, Archctocyaihus, and iStromatopora are organic, and probably Protozoan, it has proved most difficult to correlate their structures with those of modern animals. 3. I took occaHion to ineution certain errors of Prof. Moebius, due* to his limited inforrautiou on tlic subject of which he treats. He admits two of these, wliich were particularly pointed out, but taunts me with not producing others. This, however, would not have been difficult had I been disposed to enter in detail into a task so ungracious. Another example may be taken from his plate XXXV, in which he represents together, and obviously for comparison, portions of the pores or tubuli of the modern Pnly- tirnia. and an imperfect fragment of the proper wall of Eozoon. and this more especially, as appears in the text, to show the comparative fineness of the latter. But the specimen of Eozoon is magnified only 75 diameters, while that of Polytrema is mag- nified 200 diameters, or in the prnportioii of oH'i.') to 40,000. Again he has affirmed and repeats in his reply tint the casts of the canal systems of Eo::oon do not present cylindrical forms but are ''flat and uvr^'f^fO' branched stalk-like bodies." If they appeared .so to him, he must have possessed most exceptional specimens. Some canals, especially the larger, no doubt have flattened ibrms, particularly at their points of bifurcation ; but this is comparatively rare, more especially in the vastly nu- merous minute canals which are more frequently filled with dolo- mite than with serpentine. T have indeed been able to detect only a few out of very numerous specimens in which the majority of the casts of canals are not approximately round in cross .sec- tion, even in the case of the larger canals. It is a <(uestion also if some flattening may not be due to pressure , and there are flat stolon-like tubes which can scarcely be called canals.^ It occurs to me here to remark that Moebius seems to have overlooked the extremely fine canals injected with Dolomite that fill the upper and thinner calcite walls of the better preserved specimens, and which in the thinner walls are nearly as fine as the tubuli of the j)roper wall, into which in many cases they almost insensibly pass where these last are themselves filled with dolomite. Possibly these structures iiave not been present in his specimens, or may have been destroyed or rendered invisible by his methods of prejiaration, and if so this would account for • Tlie forms of the canals are jjorliaps best seen in (lecaleifiert siu'cimens ; l>nt Mr. Weston, who has done so mneli toward this in- vesti.gation, has managed to eut slices so aoturately at right anghis to th«! general (course of groups of canals, as to show tluir round cross sections with great distiu'tness. % 5 some of his concluHioii^. These tine e.'inals are best seen in well- preserved serpentinous specimens free from chrysotile veins, and etched with very dilute nitric acid. They liave scarcely been done justice to in any of the published fij^ures either of Dr. Car- penter or myself, and do not appear in those of l*roi'. Moebiufl. 4. In reply to my objection that he lias confounded the proper wall of Eozoon with veins of ehrysotile. and that both are repre- sented in his figures, he challenges me to point out which of the latter are ehrysotile and which proper wall. 01 course doing so will be of little importance to the argument, but I may indicate his tigs. 18, 43, 44 and 4S as in my opinion taken from portions of proper wall, and fig. 45 seems to show the proper wall along with ehrysotile. 1 may I'arther now point out to him that even Profs. King and llowncy in their recent paper admit that the proper wall is not continuous ehrysotile, but consists of" aciculae separated by calcareous interpolations," though they try to ac- count for this structure by complicated changes supposed to have occurred in veins of ehrysotile subsecjuontly to theii' deposition. In truth, the ehrysotile veins crosfs all the structures of Eozoon^ and those specimens are best preserved which have suffered least from this subsequent infiltration of ehrysotile into cracks formed apparently by mechanical means. This has been amply shewn in figures which I have already published, but I have now still more characteristic specimens which I hope may yet be engraved. 5. Prof. Moebiiv- sneers at my statement that when tlie proper wall of Eozoon is merely calcareous and not infiltrated, its struc- tures are invisible, and that in many cases it has become opaque, while in thick slices its structure is always indistinct ; but he should know that this is the case with all tine organic tubuli or pores in fossils penetrated with mineral matter, and eminently so with fossil Nummulites, as the researches of Carpenter have long ago demonstrated, and as any one possessing slices of the.se fossils can see for himself. I may add tliat in some decalcified speci- mens in my possession, where the proper wall has been wholly of calcite, it is indicated merely by an empty band intervening be- tween the serpentine cast and the supplemental skeleton fflled with casts of canals. 6. Lastly, he seems to think that no offence should be t:>ken at his insinuation that the figures printed by Dr. Carpenter and myself are idealized or untruthful representations, and he repeats the accusation in the following terms : '* The individual peouli- ..^ 6 arities of diagrams should not exceed the Kmita of the known variability of the real specimens, but in the Eoxooii diuiirams of Carpenter and Dawson these limits are exceeded." There could not, I think, be a more plain charm; of wilful falisification, and this is made by a naturalist who discusses Aozwh without having taken the pains oither to study it /// Hitu, or to avail himself of the larfre (ioljcctions of specimens which exist in P]nj:;land and in Canada. I can only reply that while I have been unable to figure all the peculiarities of the canal .systems of this complicated and often badly preserved fo.ssil, I have endeavoured to select the most characteristic specimens ; and that my representations are princij)al!y. nature-prints, photonraphs, and camera tracings, some of the latter by irtists in no way interested in Eozooii. Dr. Carpenter's representations appear to me to be equally truthful. Neither of us have taken the trouble to repre.sent badly preserved or imperfect specimens, any more than we siiould do so in the case of any other foi^sil, when better examples were procurable. In conn"ction with this, Moebius seems to think that in my criticism I should have gone into all the details into which he enters. This was unnece.ssary, except to i.-xpose his principal errors or mis-statements. It could not have been done without publishing a treatise as long and as expensivt'ly illustrated as his own ; and this I .should prefer to do in .>^ome other form than as a mere reply to him ; and with reference to much larger and more varied collections than those at his command. It is to be hoped that his expectations will be satisfied in this respect by a monograph which Dr. Carpenter proposes to undertake. He is good enough to add that if I will send him more and better specimens, he will willingly " forgive " me for '• disappoint- ing" him and other naturalists. 1 must say that I cannot pur- chase forgiven ne.ss on such terms, but if he will take the trouble to visit Canada and inspect my collections, he shall have every opportunity to do so. I think it is only due to the interests oi'palgeontological science to add here, that I attach more blame to the editors of the Ger- man publiciition " Palaeontographica,'' in which his memoir ap- pears, than to Prof. Moebius himself. We have been in the habit of regarding this publication as one in which the matured results of original observers and discoverers are given, and when it devotes 40 costly plates to the labours of a naturalist who is not of this character, in so far as Eozoon is concerned, and who has t not cvon studied the principal collections on which other natur- alists ecjually competent have based their conclusions, they incur a responsibility much more grave than if they were merely the conductors of a popular scientific journal, open to cursory dis- cussions of controverted points. They cannot rel'evc themselves from tills responsibility till they shall liavc publislud a really ex- haustive description of Kozoon by some one of the original workers on the subject. This is the more necessary, since if hJtK.(H)>i is really a fossil, its discovery is one ot' the most important in modern palwontoldgy, and since its claims cannot be .settled except by the most fnll itivestigation and illustration. The second {)aper referred to abov(! contains little that is new, being a re-h;ibilitation of that hypothfsis of " Methylosls," or chemic il transmutation, which the authors have already fully explained in the Transactions of the Irish Academy and else- where. Its bearing on Eozoon is simply this: — that if any one ac()uainted with geological and chemical possibilities can be in- duced to believe that the L:iurentian limestones of Canada are '' Methyjosed products,'' which originally • existed as gneisses, hornblende schists, and other mineralised silacid meiamorphics," he may be induced also to believe that h'o-.'nm is a product of nirrely mineral metamorphism. When we consider that these great limestones hav<' been so fully traced and mapped by Sir William Logan and his succes- sors on the Geological Survey ; that some of them are several hundreds of feet in thickness and traceable for great distances, that they are quite conformable with tli'' containing beds, and themselves exhibit alternating layers of limostoiu' and d lomite, with layers (tharacterized by the presence of graphite, serpentine, and other minerals, and subordinate thin bands of gneiss and pyroxene rock, the idea that they can be products of a sort of pseudomorphism of gneisses and similar rocks, becomes stupend- ously absurd, and can only be accounted foi' by want of acquaint- ance with the facts on the part of the authors. To explain tlu^ structures of hJnzoon. however, even this is not altogether sufficient, but we must su[)pose a peculiar and complex arrangianent of laminae, canals, and microscopic tubuli or fibres simulating them, to be produced in some parts of llie limestones and not in others; ajid this by the agency of several different kinds of minerals. In other words we have to suppose a conversioti on a irigantic -^ scale ofgnoi^.s into dolomite, limestone, j^raphite, Mcrpcntinc, aud other minerals, consisting for the mcst part even of difFcrcnt elements, and this at the same time or by still more mysteriouh subsequent chauucs, producinj^ imitations ol' the most delicuti- organic forms. Tiie mere statement of this hypothesis is, 1 think, sufficient to show that it ciinnot be accepted either by chemists or |»Mljcoiitol()L>ists, and if (mly serves to illustrate the difficulties which hjor.oon present.- to those who will not accept the theory of its organic origin. Dr. Otto llalin regards the matter from an entirely diffiirent point of view. He lias himself visited Canada, has collected specimens of I'Jo:j)oii, and now proposes to effect an entire revolu- tion in our ideas df the pahcoiitology of the Eozoic rocks. In a former pa|ier he hid miintaiiied that hJozoon is altouether of mineral origin, that its seri>entine is hydrated olivine, iuiries of such productions. He regards the lamina) as petrified fronds of a .sea-weed, and the canal systi'uis .is finer algte of .seve- ral genera and species. Not content with this, he describes as plants other forms found in gr.mite, gneiss, basalt, and even meteoric iron, and others found included in the substance of crystals of Arragonite. Corundum and Beryl. All these are suppo.sed to be algju of new species, and science is enriched by great numbers of generic and specific names to designate them, while they arc illustrated by thirty plates representing the ([ualnt and grotesque forms of these objects, many of which are obviously such as we have been in the habit of regarding as mere dendritic crystallisations, cavities, or im{)iirities included in crystals. Among other curious di.sct)veries the author refers to a plant which he honours me by naming Photophohn Dut tlir liiu- -Manal syHti-ms" iis Dr. ('ai'iM'ntvT had iiuni*' was nt'crssarily nu^'Uicnlrd liy tin- t'ol- lowin;; ronNidi'iatioii. of wliicl) 1 could not rid myst'lt'. -(JnciKK i.'^ formed liy watt-r and tin ri. Dawson iiud then< e went to Cote St. I'ielle. Petit Nation, there I saw tin; stratified layers and obtained a LTieat niinilM'r of jiieces of Ko/.ooiiic Limestone tind of Koy,o(ini( specimens, (n my return I examined the material. 'Die result of my examinati>ns I puhlisli here: the l.iiiK'sloiif {ft' ihr I .nuiinlmn i 1 iuisk dJ Cnuii'hi. llu dLIisI sitlinii iihiiji sli'diii ill oir iiiri/i. iiiiiliii IIS ii i^iiiit (ii\'/