Quick viewing(Text Mode)

Development of Invertebrate Paleontology in America

Development of Invertebrate Paleontology in America




(Read before the Paleontological Society, December 29,1932.)

CONTENTS Page Historical background...... 265 Field of the Paleontologist...... 269 Bibliographic aids...... 271 General statem ent...... 271 Bibliographic indices...... 272 Description and illustration of ...... 274 Service Committee of the Paleontological Society...... 277 Safekeeping of type specimens...... 278 Current problems of invertebrate paleontology...... 279

H is t o r ic a l B a c k g r o u n d

The address given annually by the retiring president of our Society has usually been the occasion for the presentation of new discoveries, or for philosophic deductions or observations on the broader phases of paleon­ tology and . In these of economic storm and stress, however, it seems more appropriate that I should take stock of the progress of our science, briefly review the , and consider the , so that we may plan and build more firmly for the future, and it is par­ ticularly desirable that someone should call attention not only to our opportunities but to certain of our failings. I have restricted my re­ marks to invertebrate paleontology because of my greater familiarity with that division of the subject. My topics are matters well known to us all; indeed, perhaps so familiar that we do not always accord them proper attention in our work, and so I venture to recall them to you in the interest of better results in our science. American invertebrate paleontology set the standard for the world during the latter half of the nineteenth century. With all our resources and superior opportunities for publication, is this the case today? And, if not, why not ? (265)

Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/44/2/265/3414963/BUL44_2-0265.pdf by guest on 30 September 2021 266 E. s.- BASSLER----INVERTEBRATE PALEONTOLOGY IN AMERICA

Paleontology had its beginnings in America in Colonial times and the early days of the Republic, when mastodon bones were frequently dis­ covered and described as remains of the gigantic men lost in the Noachian deluge. Thus, Cotton Mather, in 1714, in describing elephant bones and teeth, identified them as relics of the antediluvian giants of the Scriptures. The work of our paleontologist-statesman, Thomas Jefferson, on the Great or , read in 1797, is classic; and his continued studies of paleontology after his election to the presidency, with the conversion of a part of the White House into a paleontological mu­ seum, are known to us all. These striking extinct vertebrate remains had greatest significance for students of and , and their study was usually pursued along these lines. It was not astonishing, therefore, that the paleontology of invertebrate and plants, fos­ sils less conspicuous but more interwoven with the science of stratigraphy, did not commence until a later date. Until 1820, American was generally dominated by the Werne­ rian ideas of William Maclure, although in 1818 Amos Eaton had published his “Index to the Geology of the Northern States” which, although still tinged with Wernerism, contained the first definite attempt to arrange the geological strata of in logical . Here in the red sand­ stones of the Catskills, Eaton noted a fossil plant, identifying it as a petrified root of the common laurel. Long before this, however, in 1752, Jean Etienne Guettard had examined a collection of fossils from Canada and endeavored to establish a subdivision of the rocks, based on them, thus being one of the first men to recognize geology as an historical science. The decade in American geology which began in 1820 was, as George P. Merrill points out in his valuable volume, “The First One Hundred of American Geology,” noted for the first systematic effort in America to correlate strata by fossils. This decade was dominated by and named after Amos Eaton, the most prominent worker of the . In the second edition of his index, Eaton took up the subject of fossils, classifying them as petrifactions and conservations. The latter were fossils still composed of the same material as the living , while the petrifactions were relics made up of mineral matter which had run into the place occupied by the body before it decayed. The nomenclature of fossils was a simple matter at that time, and Eaton classified all organic remains under nine genera. For example, all belonged, according to him, to the Ichthyolites, and all shells to Concholites. It was Thomas Nuttall, in the account of his travels in the Great Lakes region published in 1820, who

Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/44/2/265/3414963/BUL44_2-0265.pdf by guest on 30 September 2021 HISTORICAL BACKGROUND 267

made the first serious attempt to correlate the rocks of North America by means of invertebrate fossils. Nuttall antedates by fifteen years similar efforts by Morton on the of the Atlantic Coastal Plain, and by a longer time the researches of James Hall and other New York . Shortly after Nutt all’s work, there appeared some of the earliest descrip­ tions of of American invertebrate fossils. Among these were those published by John J. Bigsby, a surgeon of the British Army, who was stationed in Canada. So much of the work of the next fifty years of American geology and paleontology, beginning in 1830, was done by the state geological surveys that Dr. Merrill has appropriately named it “The of State Surveys.” Early in this era Maclure and Eaton were still active, but there soon rose to prominence such paleontologists as Timothy A. Conrad and James Hall. Systematic paleontological research upon the Tertiary shells of North America commenced with Conrad’s first work upon the subject in 1832. With the inauguration of the Geological Survey of New York in 1836, and the appointment of James Hall as a member, in­ came into its own, and the great series of New York paleontologic volumes was inaugurated. In other states initiated surveys, many of them devoting at least a part of their publica­ tions to paleontology. Ohio, Illinois, and Minnesota are conspicuous ex­ amples of states which added especially noteworthy contributions to in­ vertebrate paleontology. Then, in the middle of the century, Elkanah Billings was appointed on the Geological Survey of Canada under Sir William Logan, and for two decades he did excellent work upon the Paleozoic invertebrate fossils of that country. The latter half of the Era of State Surveys was conspicuous for various exploring expeditions to the West, which resulted especially in important additions to our knowledge of post-Paleozoic fossils. The Civil War brought forth men of great physical and moral courage for these expedi­ tions. The West was now beckoning, and Congress was willing to appro­ priate funds for its exploration. At first military in their , these expeditions soon added geographic explorations to the scope of their work. Then military, geographic, and geologic aims were combined, and finally geological and natural researches became the prime objects of these endeavors. Hayden’s “Geological Survey of the Territories,” King’s “Geological Survey of the 40th Parallel,” Powell’s “Survey of the Rocky Mountain Region,” and Wheeler’s “Survey west of the 100th Meridian” are well known. Meek was the outstanding paleontologist of these surveys, although not officially connected with any of them. He early became

Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/44/2/265/3414963/BUL44_2-0265.pdf by guest on 30 September 2021 268 E. S. BASSLEE----INVEETEBEATE PALEONTOLOGY 11ST AMEEICA

associated with Hayden, and continued to study the fossils collected by the territorial surveys until after Hayden’s death. Arriving in Washington in 1858, Meek had a room in the Smithsonian building where he lived and did all his work during the rest of his . Had he possessed the of a Hall and been of a less retiring disposition, he undoubtedly would have become the outstanding paleontologist of this period. The territorial explorations culminated in 1879 in the founding of the United States Geological Survey, the greatest institution in the world’s history for the increase of geological knowledge. Under the Survey, invertebrate paleontology has been encouraged equally with vertebrate paleontology and , and the many important memoirs by the paleontologist-director, Charles D. Walcott, and other members of the organization, as well as by others not on the staff, today form a most essen­ tial part of every American paleontologist’s library. The twentieth cen­ tury has seen a continuation of both national and state surveys, and an increasing appreciation of invertebrate paleontology. Students of invertebrate paleontology of the nineteenth century com­ prised comparatively few professional men, recognized as the logical persons to describe fossil , and a large number of amateur col­ lectors, whose ambition it was to assemble a cabinet of fine specimens or describe a new species. An amateur would sometimes graduate into a professional; first, by independent publication on a small scale; then, perhaps, by temporary work on a state survey, and finally through recogni­ tion of his abilities by appointment to some permanent position on the na­ tional survey or in some large museum or university. Thus did an Ulrich arise, and, indeed, most of the master of paleontology of the nineteenth century underwent such a training. College education had little, and in most cases nothing, to do with their training. The col­ lecting instinct, coupled with energy and natural ability and a great love of nature, as well as environment, were largely, if not entirely, respon­ sible for the work of these men. The twentieth century has produced the college bred paleontologist, and so far has seen a great decrease in the number of amateur collectors. Today, the student often attains his majority before discovering that he wishes to make paleontology his life work. Thereby he loses all the early years of training and interest that were formerly considered essential to success. In such cases, the science has often become a vocation, pure and simple, instead of an avocation pursued as a vocation. The automobile has done its part; for in these days of swift transportation few travelers have the time to stop and search the dusty outcrops for fossils, if indeed

Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/44/2/265/3414963/BUL44_2-0265.pdf by guest on 30 September 2021 HISTORICAL BACKGROUND 269

they can even see them as they speed along. In the mad rash of our machine age, fewer men are enjoying as amateur'collectors the pleasures, simple perhaps, but all the more pleasant, of the discovery and study of interesting fossils. It is true that there are more professional paleontolo­ gists and more research work is produced, but there are fewer paleontolo­ gies of New York or Minnesota published.

F ie l d o f t h e P aleontologist

While the science of paleontology is, strictly speaking, concerned only with the study of organisms existing previous to the present time, the successful paleontologist of today must have a broad training in other branches of geology. As a rule, the early American paleontologists were paleobiologists; that is, describers of species. They did include in their descriptions the general horizon and locality of the species, but the stratigraphy of the area supplying the fossils was seldom considered. With increasing knowledge, a record of the precise locality and exact stratigraphic horizon became so necessary that in order to obtain this detailed information for many of the described species, additional re­ search was required. This led to faunal studies by zones, in consequence of which the paleontologist had either to become a student of stratigraphy or to depend upon the work of others who often had little paleontologic knowledge. Thus, the paleobiologist developed into the stratigraphic paleontologist. Stratigraphy is practically impossible without fossil evi­ dence, for the law of the order of superposition upon which it is based, breaks down in the absence of fossils. Close stratigraphic work, accompanied by faunal studies, showed why areas of apparently continuous deposition, such as the Cincinnatian limestones and shales of the Ohio Valley, did not exhibit an unbroken story of the evolution of their contained life. The reason was plain when it was learned through stratigraphic studies and mapping that en­ tire formations, well developed elsewhere, were absent in the Ohio Valley, or were represented there only by overlapping feather edges. Then still another factor was introduced when it was discovered that the faunas of the past originated in definite oceanic basins, and were as characteristic of them as are modern faunas of the present oceans. The geographic dis­ tribution and change of thickness of the formations and the composition of their contained faunas gave the clues to their ocean origin, and by such means the Arctic and Gulf faunas of the Paleozoic were discovered to

Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/44/2/265/3414963/BUL44_2-0265.pdf by guest on 30 September 2021 270 E. S. BASSLEB---- INVERTEBRATE PALEONTOLOGY IN AMEEICA

differ as greatly—yes, even more than the corresponding ones of the present time. The distribution of the strata with these faunas of various origin in­ dicated that the was invaded repeatedly by different oceans, more or less regularly or in a rhythmic manner, an Arctic invasion, for example, being followed by a flooding of Gulf , and then an Atlantic submersion by a Pacific one. It is no wonder that continuous evolution could not be discovered with such breaks in the record; indeed, it is probable that the record of the evolution of life under such conditions can be worked out only by a study of the successive, although interrupted, invasions from the same sea. Furthermore, the principles of sedimenta­ tion must enter into the work of the paleontologist, and the ecologic con­ ditions of the time should also receive his attention. The subject has now become so complicated from the taxonomic side, particularly by the introduction of so many names for the same species, that a legal training is almost a necessity if one is to solve some of the questions arising in nomenclatorial problems. , also, is the province of the paleontologist, for the fossils tell the story of faults and similar phenomena most accurately. In the work of the paleontologist has been particularly exemplified in the relation of to the oil industry, but it should also be remembered that fossils are often an important aid in the discovery and determination of the origin of certain metallic ores. The species-maker, therefore, of several decades ago has now changed into a with training in many diverse branches of the science, if he has evolved with the progress of paleontology. This increase in the magnitude of the field is brought out in the records of the Geological So­ ciety of America, where at the end of 1931, 155 of the 607 Fellows were Fellows of the Paleontological Society, which latter society itself has a total membership of 425. With such a broad field of endeavor, it is evident that the individual paleontologist must devote a large amount of time to the study of the vast literature and the preparation of bibliographies on his special subjects unless, by concerted action, such aids and timesavers can be completed for the benefit of all, once for all. A good beginning along such lines has been made for invertebrate paleontology in America, and in the fol­ lowing pages I present a brief outline of the results achieved so far, with suggestions for future work in this and other subjects, of much value to all, but of greatest value to the beginner in the science.

Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/44/2/265/3414963/BUL44_2-0265.pdf by guest on 30 September 2021 FIELD OF THE PALEONTOLOGIST 271

The technique of the preparation of fossils is now available to every­ one with the publication of the volume entitled “Paleontologisches Prakticum;” written by 0. Seitz, the invertebrate paleontologist, and W. Gothan, the paleobotanist, both of the Prussian Geological Survey. This book has been translated into English by B. F. Howell, and it is hoped that it may be published in America in the near future. The American edition is expected to be greatly enlarged by the inclusion of information on the technique of a wider field, and chapters by specialists on the methods of study of their own particular groups.

B ibliographic A id s

GENERAL STATEMENT The student of North American paleontology is fortunate in having the literature very completely listed and indexed in the splendid set of volumes, the “Bibliography of North American Geology,” by John M. Nickles, and by the earlier work of Darton and Weeks published by the United States Geological Survey. When his researches embrace foreign publications—and no problem should disregard the literature of other countries—his troubles begin, for there is no work abroad comparable to that of Nickles. Few of our paleontologists, however, have realized that there are certain general bibliographies useful in this connection, and American invertebrate paleontology particularly has suffered from a lack of study and comparison of the little known, foreign literature. To remedy this the Paleontological Society printed, in 1930, in volume 41, Bulletin of the Geological Society of America, a list of general bibliographies of foreign paleontological literature, with valuable remarks and comments as to their contents, compiled by Ignatius McGuire, of Princeton Univer­ sity. McGuire’s entire list deserves repetition, but in it there are certain works which are indispensable to the serious student, and for that reason I am now repeating them. First, there are the catalogues of scientific and other papers and books in the libraries of various societies in London, which should be thoroughly searched when one is working up the biliogra- phy of his subject. Among these the “Catalogue of Scientific Papers,” published by the Royal Society of London, is most useful, as is also the “Catalogue of the Library of the British Museum” (), where bibliographic information of all kinds is included. Almost equally helpful are the catalogues of the Geological Society of London, the Lin- nean Society of London, the Royal Geographical Society of London, and

Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/44/2/265/3414963/BUL44_2-0265.pdf by guest on 30 September 2021 272 E. S. BASSLER----INVERTEBRATE PALEONTOLOGY IN AMERICA

the Zoological Society of London. Then, for more detailed references to paleontologic literature, abstracts, and lists of species and genera, the following works must be consulted.

International Catalogue of Scientific Literature. Paleontology. 1901. May, 1916. 14 volumes published by the Royal Society of London. Zoological Record. Volume 1, 1864, to date published by the Zoological Society of London. Concilium Bibliographicum Index Universalis. Published on cards by the Bibliographic Council, Zurich. Biological Abstracts. Commenced with literature of 1926. Published at Philadelphia, Pa. Geologisches Zentralblatt. Volume 1, 1901, to date. Leipzig. Neues Jahrbuch für Mineralogie, Geologie und Paleontologie. Stuttgart.

One of the most important steps forward in paleontology in recent years has been the establishment of the Paleontologisches Zentralblatt, the first abstract journal devoted entirely to our science, the first issue of which appeared in March, 1932, under the editorship of O. H. Schinde- wolf. With proper encouragement, this journal will insure the prompt publication of abstracts of the paleontological papers of the entire world. Such encouragement has begun, for arrangements have been concluded whereby Dr. Schramm, editor-in-chief of Biological Abstracts, will ex­ change abstracts with Dr. Schindewolf, with resulting mutual advantage to the journals they represent and for the greater benefit of paleontology throughout the world. It is to be hoped that eventually the geologic literature of the world outside of North America can be published in a form comparable to the Nickles" bibliographies, and I can think of no undertaking which would benefit a greater number of students in our science.

BIBLIOGRAPHIC INDICES Systematic paleontology is now so burdened with synonyms or incor­ rect identifications that one must spend a large percentage of his time on the literature in working up the correct bibliographies of his species. As many paleontologists do not have access to large libraries, this part of their study must be neglected, with the result that there is necessarily a tendency to increase the synonymy. The need for complete synonymic bibliographies of invertebrate fossils is, therefore, very evident, and I am happy to say that materials are in hand for publishing those dealing with North America as soon as printing funds become available. The Cam­ brian bibliography by C. E. Eesser is practically up to date. The Ozar- kian, Canadian, , and systems have been kept up to

Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/44/2/265/3414963/BUL44_2-0265.pdf by guest on 30 September 2021 BIBLIOGRAPHIC AIDS 273

date by myself since 1915, when my bibliographic “Index of American Ordovician and Silurian Fossils” was published. The species are kept well in hand by E. M. Kindle and his associates, and the remain­ ing part of the Paleozoic is being cared for by Marvin Weller and 6. H. Girty, each having an extensive catalogue of invertebrates. In the , Boyle’s catalogue brings the literature of invertebrates up to 1892, and Whitney’s work carries it to 1918. The literature since that date has been catalogued and is available in the files of the United States Geological Survey. Likewise, a catalogue of species for North America, commenced by W. H . Dali and continued by his suc­ cessors, is available to students at the United States Geological Survey. With a little encouragement all these bibliographies could be quickly prepared for publication, and one of the bugbears of paleontological sci­ ence could be removed forever. Unfortunately, most of these works cover only the Americas, and similar volumes must yet be produced for the rest of the world. The literature of paleontology has become so enormous that it is almost impossible even for specialists in restricted fields to assemble compre­ hensive libraries covering their subjects. This condition will, no doubt, lead ultimately to the preparation of illustrated card catalogues of spe­ cies, if progress in systematic paleontology is not to be retarded. E. M. Kindle has offered a plan for publishing an illustrated catalogue with revised descriptions and other information of the Devonian fossils of North America, which is so feasible and also so reasonable in cost to the subscriber that he deserves all possible encouragement. Our Society has gone on record as approving not only his proposal but also one to extend it to the fossils of the other systems of the American Paleozoic. Such projects can not succeed without the hearty cooperation of our member­ ship, and it is hoped that all who are able will contribute to this work as a labor of love. Another urgent need of our science is the publication of up-to-date systematic classifications and keys covering the various groups of in­ vertebrate fossils. These should include lists of the literature and reviews of the classification with generic descriptions, as well as a general sum­ mation of past work, so that the modern student will have a firm basis for research work and will not be required to lose so much effort indi­ vidually in compiling such data. Such a publication is a great to workers already engaged in the field involved, and frequently leads others to take up such studies. This is well illustrated in the case of the conodonts, the toothlike structures now believed to be the teeth of primi­

Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/44/2/265/3414963/BUL44_2-0265.pdf by guest on 30 September 2021 274 B. S. BASSLER----INVERTEBRATE PALEONTOLOGY IN AMERICA

tive Paleozoic fishes or some still simpler . These had been neglected for several decades in both Europe and America until, in 1926, a review of the subject and a classification with generic descriptions and illustrations appeared, which apparently aroused such interest that a number of students are now specializing in this group and publishing excellent articles. A similar article on the classification of Paleozoic Ostracoda, published in 1923, may have aided in stimulating the many students who have taken up the study of this group since that date. Cer­ tainly the most striking development in invertebrate paleontology in recent years has been the growth of micropaleontology, and especially the study of the foraminifera, ostracods, and conodonts.

D e s c r ip t i o n a n d I llustration o f F o s s il s

After the bibliographic references have been studied and the species identified with previously described forms or determined as new, next in order comes the matter of description and illustration. The relative value of these two items has been reversed, in my opinion, almost invari­ ably in the past. Usually, following the cumbersome methods of some of the earlier paleontologists, the species has been described in the great­ est detail according to a formula, but illustrated very inadequately. Pos­ sibly it has been believed that illustration should give merely the general idea of the fossil, leaving the specific characters to be furnished by the description. Page after page devoted to the description of a single species, embodying a detailed account of the generic characters and even of the , as has often been done in the past, is, in my , not only useless, but very wasteful. Few of us ever wade through these ponderous descriptions, but many go immediately to the illustration for identifica­ tion. It seems to me that more effort should be expended in the prepa­ ration of adequate, as well as correct, illustrations, and that the specific description should, whenever possible, be limited to measurements and a few lines of succinct characterization'and comparison with some well- known species of the same genus which has been more fully described. In the matter of illustration our science has gone through a series of interesting phases. The early workers most often employed free-hand drawings, made by themselves or by some artist who knew little, if any­ thing, of paleontology. Then came a period of larger monographs, such as those of D’Orbigny in France, when the author made free-hand sketches of the object, and the artist converted these into schematic drawings. The many plates of , ostracoda, and foraminifera published at that time

Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/44/2/265/3414963/BUL44_2-0265.pdf by guest on 30 September 2021 DESCRIPTION AND ILLUSTRATION OF FOSSILS 275

suffered because of such drawings, for the illustrations are so diagram­ matic that many of the species can not be accurately identified, and so require refiguring. A great advance was made in the plates of the New York Survey, when more exact methods were used in making the draw­ ings. Many of the Hall types still retain the lead pencil cross-marks which divided the fossil into quarters, each of which could thus be drawn to more accurate scale. In the hands of competent artists, this was, by far, the most satisfactory method of illustration, and gave pleasing results, as the New York volumes fully attest. However, this method was unduly expensive, and as a result, retouched photographs came into use, especially in the publications of the United States Geological Survey. This method was undoubtedly the best, when the retouching was done by the student himself, who understood the characters which should be emphasized or reduced. Here again a nonscientific artist can ruin the best of photo­ graphs, and so, within comparatively recent years, some museums and surveys have required unretouched photographs to accompany publica­ tions. In most cases, this has led to deplorable results, because the im­ perfections of the specimen invariably photograph more distinctly than the specific characters. Certain plates of recent publications are so bad in this respect that even the originals of the photographs can not be matched with the illustrations themselves. In this connection, for the promotion of better illustrations, I should call attention to the use of the whitening process in photographing fos­ sils, the details of which have been published in several works on micro­ paleontology. It will be remembered that by the use of an apparatus whereby the fumes of strong hydrochloric acid and ammonium hydrox­ ide could be combined by blowing through tubes, there resulted the white sublimate of . This, when directed against the fossil, condenses as an ivory white coating which gives to the specimen the even tone necessary for the best results in photography. The objection has been made that this coating obscures the structure or becomes granu­ lar, and thus gives a wrong impression in the photograph. However, this is a matter of technique, for if the tubes are kept dry and the sublimate not applied too strenuously, a bluish white, often scarcely visible, and absolutely smooth coating, which will show no structure even under a magnification of 25 diameters, will form on the fossil. I have photographed thousands of specimens of glassy bryozoans and ostracods at such an en­ largement, with more success in the matter of exhibiting specific details than can be had in any other way. Indeed, in my studies I keep the whitening apparatus constantly at hand for use in bringing out the details

XVIII—B ü l l . G e o l . S o c . A m ., V o l . 4 4 , 193 3

Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/44/2/265/3414963/BUL44_2-0265.pdf by guest on 30 September 2021 276 R. S. BASSLER----INVERTEBRATE PALEONTOLOGY IN AMERICA

of poorly preserved specimens or for material requiring special attention. By this method, the specific details upon certain vitreous organisms, such as foraminifera, ostracods, bryozoans, and , flash into plain view when gently and carefully whitened. By this process, also, the varying colors in the rock, which make accurate photography difficult, are elimi­ nated, and the high lights and shadows are correctly distributed. In re­ touching such photographs, the specific details are so well shown that almost all that is necessary is to strengthen the outline and perhaps in­ tensify a few shadows here and there. The economic and artistic preparation of plates is another subject to which most American paleontologists could well direct more of their efforts. Considered from the standpoint of economy, it is well to realize that routing a plate—cutting out, with an engraver’s tool, all the super­ fluous background, and inserting the numbers of the illustrations in clear cut figures— adds a further expense of at least 60 per cent to the cost of the plate. Any method to eliminate this unnecessary cost is desirable. Mounting the illustration upon a black background and using white numbers makes a most artistic half-tone plate, as evidenced by the recent publications of Cushman. No routing is necessary in such cases, and the background becomes still blacker because the screen, employed in photog­ raphy for the half-tone, does not register but leaves the background a solid black. Another method to eliminate the cost of routing is to paste the illustrations, carefully trimmed to their edges, upon a white cardboard plate, and ink in the numbers. In this case, the background will emerge as slightly shaded but not unpleasing to the eye. Here it should be noted that a photograph under by half-tone loses at least one- fifth of its original contrast, so that the originals should have a slightly darker shade than the one desired in the final prints. Much space is lost by the improper arrangement of figures on the plate, and as a result, a corresponding amount of money is wasted. In many eases, also, the figures are arranged inartistically, and the plate is often so unbalanced as to hurt the eye, at least of the artist. Since in most of our publications the author prepares and arranges his own plates, and there is no further check upon it from the editor or publisher, it is desir­ able that all of us should study some standard form. For this purpose, the paleontological publications of the United States Geological Survey are recommended. Excellent suggestions for the preparation of paleon- tologic illustrations are given in an article by J. B. Beeside, Jr., published in 1930, in volume 4 of the Journal of Paleontology.

Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/44/2/265/3414963/BUL44_2-0265.pdf by guest on 30 September 2021 SERVICE COMMITTEE OF THE PALEONTOLOGICAL SOCIETY 277

Service Committee of the Paleontological Society

The scope of paleontology has increased so tremendously that a clear­ ing house is now just as much of a necessity as in commercial fields. The Paleontological Society has recognized this need, and the Service Com­ mittee is acting as such a clearing house for the paleontologists of North America. The breadth of its field will be noted from the following. Paleontologists wishing to sell or purchase fossils, or exchange them, are put in touch with each other. Those wishing new positions have been placed in contact with institutions where there was an opening or a possibility of one. The committee has prepared an up-to-date list of the paleontologists of the world, which is at the command of American students, and has proven very useful to them. This list contains infor­ mation concerning the field of research of most paleontologists, and every effort is made to keep this information up-to-date. American paleontolo­ gists have been assisted in securing photostat copies of rare publications of both Europe and America, and in obtaining copies of rare books and papers which they wish to purchase. The chairman of the committee has been called on for advice of all sorts, especially by young paleontologists. In thè few years of its existence, this committee has shown that its service is of real value to the , and that it is also necessary and fills a long desired need. The Secretary of our Society, under instructions from the Council, has assembled data for the purpose of considering the formation of an international paleontological union. In a report submitted at this meet­ ing, he has indicated that there are at present some 2,200 active paleon­ tologists, of whom somewhat more than 1,000 are primarily invertebrate paleontologists, with 400 of these classed as micropaleontologists. Of the 2,200 total, some 1,000 are residents of North America, nearly 900 of them dwelling in the United States. With such a large number now working in the science, it is apparent that the time has arisen, when, by general agreement, research in paleontology should be put on a more systematic basis. Too often the subjects under study have been selected casually, and without any thought that someone else might have been better fitted or more suitably located to do the work. The majority of paleontologists today are engaged in museum work, on Federal or State geological surveys, in teaching at our universities, with industrial concerns, particularly oil companies, or as students fol­ lowing the science as a hobby. Most of those attached to the large uni­ versities and museums or government surveys have access to large libra­

Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/44/2/265/3414963/BUL44_2-0265.pdf by guest on 30 September 2021 278 R. S. BASSLER INVERTEBRATE PALEONTOLOGY IN AMERICA

ries. Such persons should feel it their duty to do more than their share of bibliographic work and the preparation of such lists and manuals as require a broad survey of the literature. In this same group, one should find the specialists on particular divisions of the and plant kingdoms, because it is there that the most extensive paleontological collections are found. Our Service Committee could, if so directed, use its good offices in forwarding such work. Another field in which there is much opportunity for research is the description of local faunas; i. e., study of the of the particular formation or zones of a formation in a definite area. Hitherto, too many of our researches have been of a diverse nature, including species from widely separated horizons and localities, without any unifying purpose. Here is a field for the student following our science as an avocation, for intensive work on almost any local field in the United States is sure to bring forth good results. Dr. Kindle’s plan of publishing new descriptions and illustrations of described Devonian fossils, mentioned previously, if extended to the other Paleozoic systems, will require much tim e; so, in the meantime, no oppor­ tunity should be lost to refigure little known or poorly illustrated species. A. F. Foerste has demonstrated the great value of such work in the case of the Paleozoic , and his example can well be followed by students of other classes. On the other hand, it is sincerely hoped that the policy, followed by one of our leading organizations a few years ago, of rejecting all illustrations of previously described but unfigured species from one of their monographs, be judged as most detrimental to the science. In this particular case, a large part of the value of the resulting monograph was sacrificed in order to save the expense of a few plates, and undeserved criticism was called down upon the of contributors.

S a f e k e e p i n g o f T y p e S p e c i m e n s

With the increasing economic importance of invertebrate paleontology, the value and the necessity for careful preservation of type specimens have grown correspondingly in the minds of students. In the early days of the science, types were considered of no more importance than any other examples of the species, and I know of cases where they were sent out to collectors and institutions as so many duplicates. Again, they were placed in the general study series of university collections, where they were at the mercy of the students after year, finally, of course, becom­ ing lost. Now, types are regarded of such importance that even their


Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/44/2/265/3414963/BUL44_2-0265.pdf by guest on 30 September 2021 SAFEKEEPING OF TYPE SPECIMENS 279

classification has become complicated, and a considerable amount of liter­ ature has been printed about this subject alone. Our Secretary, in 1929, Volume 40, Bulletin, Geological Society of America (pages 215-220), published an excellent resume of the various kinds of type specimens and the methods for distinguishing them. Not so long ago, some paleontolo­ gists were incited to the description of new species, partly to increase the value of their private collections by the types thus added to it. Certain of these collections have been lost entirely, but, fortunately, most of them have been purchased by the larger museums, and the types saved to science. To prevent such losses in the future, I suggest that all paleontologists, for the good of science, encourage the feeling that type specimens should be deposited safely in a well-endowed museum or university collection. I am glad to say that most of the micropaleontologists have felt thus with­ out any urge whatever, and have placed their types in the large museums. Since the danger of loss by transit through the mail is great, most mu­ seums hesitate to loan types; but this, instead of being an objection to the plan I am advocating, should be in its favor. Plaster of Paris or guttapercha casts of the are so easily made, and almost as useful for purposes of study as the original types themselves, that they can be used for transit through the mail.

C u r r e n t P r o b l e m s o f I nvertebrate P aleontology

A review of the various groups of invertebrate' fossils brings up some interesting features regarding what has been accomplished and what is still required. Certain classes have been studied in much detail, while in many others hardly a beginning has been made. Thus, in the , the foraminifera, on account of their use in economic geology, have been the subject of many publications. With the study of the Paleozoic forms in the hands of Dunbar, Henbest, and others, the post-Paleozoic faunas under description by Cushman and Galloway and their associates, and the work of Vaughan on the larger Tertiary forms, the order is receiving deserved attention. The Eadiolaria, on the contrary, have been so little studied in America that practically a new field of research is offered by them. These play such an important part in the composition of many siliceous rocks in Europe that it is unquestionably only a matter of effort and time before they will be found in equal abundance in Ameri­ can strata. European students of Radiolaria have been numerous, and have discovered the remains of these animals at all horizons; indeed, it

Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/44/2/265/3414963/BUL44_2-0265.pdf by guest on 30 September 2021 280 R. S. BASSLER----INVERTEBRATE PALEONTOLOGY IN AMERICA

has been stated that Radiolaria, occurring in Brittany in quartzites inter­ bedded with pre- schists, are the oldest known animal fossils. American fossil also require much study, for now more than a generation has elapsed since an important work on them has been published. Walcott’s work on Middle Cambrian sponges, Ulrich’s and Everett’s on Ordovician forms, and Hall and Clarke’s upon Devonian glass sponges constitute the major publications. Much anatomical work is still necessary in this group, and abundant material is available in the Ordovician and Silurian of the Mississippi and Appalachian valleys. Post-Paleozoic sponges are comparatively rare in America in contrast with European deposits; hence, correspondingly little has been done or can be expected here. Excellent opportunities for research are presented by the Receptaculi- tidae, that curious group of sunflower-like, Paleozoic invertebrates, often found abundantly in Ordovician rocks. Their position and classification are as wholly conjectural as ever, and it is even possible that they are plants. Turning next to the coelenterates, it is astonishing how little work has been accomplished in America in the last three decades upon the Tetra- coralla. Abroad, the efforts of W. D. Lang and Stanley Smith in deter­ mining the true nature of the types of many genera are most praise­ worthy, but other students have added so many new genera on such a slight foundation that a great amount of reinvestigation must be con­ cluded before progress can be made in the study of the Paleozoic corals. Again, certain students have published volumes upon the same faunas, without regard to the rules of nomenclature or reference to each other, so that synonyms abound. I refer particularly to the Middle Devonian corals of the Ohio Valley where Hall, Rominger, Greene, and Davis have named many species, with little attempt to recognize each other’s work. Mesozoic corals, long considered as almost nonexistent in our country, have had some attention. The forms have been discussed and received excellent study by Smith and Shimer during the past few years, and J. W. Wells is now studying our forms. Vaughan and others, working upon the Cenozoic corals, have kept this branch of the subject nearer up to date than the others. The systematic position of the Tabulata is as uncertain as ever, and interesting lines of research are offered by this suborder. Among the Hydrozoa, the stromatoporoids have received little attention since the studies of Parks, which ended about 1910. The imperfection of the internal structure of many of these so-called hydroid corals makes

Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/44/2/265/3414963/BUL44_2-0265.pdf by guest on 30 September 2021 CURRENT PROBLEMS OF INVERTEBRATE PALEONTOLOGY 281

their study especially difficult, but here the student must ever be on the lookout for specimens with the interior better preserved than usual. Devonian stromatoporas, so abundantly represented in the Mississippi Valley, are especially in need of study by modern methods. The grapto- lites, until recently classed at the end of the coelenterates but now referred to the bryozoa by Ulrich and Ruedemann, have always interested students more, in proportion to other groups, so that their study has been con­ tinued more or less actively. The general faunas were supposed to be fairly well described, so the 1928 work of Cumings and Shrock, on the Niagaran of North Indiana, was a pleasant surprise and indication that the field still affords good opportunities. Discoveries of recognizable remains of fossil flat and thread are so rare that publication has usually kept pace with them. Walcott’s work on the of the Middle Cambrian of British Columbia is evi­ dence of the possibilities for research when the right conditions for preservation are found. The tubicolous annelids, with their calcareous tubes, afford many opportunities for research, while the jaws, quite distinct from the conodonts, are known to occur in many formations from which no species has as yet been described. These annelid jaws are insoluble in weak acid, so that it is only a matter of technique to release from the solid limestones free examples for study. Throughout the Echinodermata, with the exception of certain echinoids and blastoids, entire examples are usually so rare that researches must wait upon their discovery. It is only special collections like the Springer collection at Washington, the result of the life work of many collectors, that can afford material for detailed study. However, opportunities for research in the Echinodermata are still available, as shown in the stimulat­ ing paper on fossil Holothuroidea by Croneis and McCormack. This work contains not only descriptions and illustrations of many new species from rocks hitherto not supposed to contain them, but also all the information upon fossil and recent examples of these , needed by subse­ quent students. E. T. Jackson’s monograph on the Paleozoic echini, issued a generation ago, is not only a classic of American paleontology, but proved to be a stimulus to European students. In the Mesozoic and Cenozoic, there is need for revision and continuation of the work of Clark and Twitchell. In the Bryozoa, the post-Paleozoic forms in America have received per­ haps more than their proportionate share of attention, but the Treposto- mata and Cryptostomata, restricted to the Paleozoic, require not only a

Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/44/2/265/3414963/BUL44_2-0265.pdf by guest on 30 September 2021 282 R. S. BASSLER---- INVERTEBRATE PALEONTOLOGY IN AMERICA

close study of many new faunas, but, I regret to say, most of the work of recent years is of such low grade, especially as regards illustration, that it must be done over. Illustration of the internal structure of such bryozoa by photographs of thin sections, instead of drawings, has been responsible for most of this poor work. Unfortunately, the lens of the camera does not eliminate, as does the eye, the aspects produced by light rays passing through the calcite of the section, with the result that the internal structure of the fossil is either blurred or completely ob­ scured. By proper manipulation of the light, good thin sections can be photographed successfully, but it is best in all such cases to bring out the structure by strengthening the essential features in the photograph with pencil or pen. Better still, a part of the illustration can be left as an unretouched photograph, but the rest should be retouched or replaced by a drawing. It is unfortunate, as noted before, that certain American universities insist upon the use of only unretouched photographs in their publications. The results are generally atrocious. The beautiful Cryptos­ tomata, with their lacelike fronds and geometrical external structure of the zooecia, require careful illustration of their surface features. It is heart­ rending to compare the practically useless figures of many recent works with those of 1890 in volume 8 of the Illinois Geological Survey. Nomen­ clature could well devise some rules as to the validity of species illustrated by useless figures. Carelessness is at the basis of such illustrations, for anyone can find out from the literature how good figures can be made. If the Trepostomata and Cryptostomata, perhaps the most abundant fossils in American post-Cambrian Paleozoic rocks, are to be of use in stratigraphie work, many careful students must work upon them. These students must, first of all, be willing to clear up the poor work of the past— a thankless task—before proceeding into new fields, so as to avoid fur­ ther complications. The number of formations crowded with unstudied bryozoa is really astonishing. For example, in the Trenton group alone the Curdsville, Hermitage, Wilmore, Bigby, Flanagan, Perry ville, and Cynthiana formations of the Ohio Valley afford large bryozoan faunas with many new species. Equivalent formations in other parts of the country are often just as rich in unstudied species, and equally rich opportunities for the study of the Trepostomata exist, particularly in the Chazyan, Rich­ mond, and succeeding groups of the Paleozoic. The study of the fossil in America has always been in good hands, and is still receiving careful attention, as shown by the excellent generic work recently issued by Doctors Schuchert and Cooper. Per­ haps no other class of invertebrates has experienced so many taxonomic

Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/44/2/265/3414963/BUL44_2-0265.pdf by guest on 30 September 2021 CURRENT PROBLEMS OP INVERTEBRATE PALEONTOLOGY 283

changes within recent years, as one may readily see from the work of Dr. Schuchert and Miss LeVene; but such changes are in line with the prog­ ress of study and are for the good of the science. monographs have almost always, in the matter of excellence, ranked higher than those of other groups of fossils, and this high standing has been maintained in recent years in those issued by Stuart Weller, Raymond Moore, Carl Dunbar, and Schuchert and Cooper. The Cambrian and post-Silurian brachiopods have proportionately received more attention, but much re­ mains yet to be done on those of the intermediate systems. Among the Paleozoic , the Pelecypoda perhaps require most attention; for although many species have been described, the generic is in great need of revision. This applies particularly to Silurian pelecypods and the many genera of the Devonian. As for the , although the Ordovician and later Paleozoic faunas have been fairly well described, the intervening Silurian species require much ge­ neric study. Since the excellent monographic studies upon early Paleozoic gastropods and pelecypods published by Ulrich in the “Paleontology of Minnesota,” little advance has been made upon the classification of these two, difficult groups. Paleozoic cephalopods have for years received the careful attention of A, P. Foerste, and his excellent results now seem destined to be continued in the studies of A. K. Miller. These researches have been restricted almost entirely to the pre-Devonian cephalopods, so that a similar revision of the Devonian and Carboniferous species is still necessary. Part of this need will doubtless be met by the studies of Plummer and Scott on Carboniferous forms. In the remarks upon the Mollusca no mention has been made of the abundant undescribed molluscan faunas in the Ozarkian and Canadian systems. I am happy to say that arrangements have been made where­ by the descriptions of these interesting progenitors of the later, better known, Paleozoic forms will be issued in the near future. The late lamented and beloved J. Perrin Smith has placed the Ameri­ can Triassic cephalopods on such a firm basis that future students will find the path made easy for them, but much work is still to be done on other Mesozoic mollusca. Pew thorough studies of any group of and Cretaceous mollusca have been published in recent years except those of the Cretaceous pelecypods and gastropods of the Coastal Plain and the studies in Mexico of Burckhardt and Böse. Most of the -work on the ammonites remains to be done for both the Jurassic and Cretaceous, and much of that on the other mollusca. In the Cenozoic there has been a

Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/44/2/265/3414963/BUL44_2-0265.pdf by guest on 30 September 2021 284 R. S. BASSLER----INVERTEBRATE PALEONTOLOGY IN AMERICA

comparatively large number of active students, and the field has been more fully covered, though even here there is no lack of opportunity. In the Crustacea, the most fertile field of study at present is in the of the Canadian and Ozarkian systems, well represented in the collections of the United States National Museum, where researches upon them are in progress. The trilobites have always been a favorite subject of study, and numerous articles upon them have been published, as evi­ denced by the series of bibliographic lists, both of the literature and of the genera and species, issued by A. W. Yogdes. The result is that the number of new species which may be expected to be found in the post- Ozarkian systems of the Paleozoic is perhaps smaller than in the case of other classes of fossils. Fossil Ostracoda have received most uifusual attention in recent years, with their increasing importance in economic geology. Furthermore, students of this order during the past two decades have, as a rule, done their best to furnish faithful illustrations, in contradistinction to the authors of the last century, who illustrated their species with such diagram­ matic drawings that their work, in many cases, has to be done over. The Upper Paleozoic ostracods have received particular attention recently in America, and I am glad to say that a bibliographic index of the Paleozoic Ostracoda of the world, embodying bibliography, synonymy, classification, and other features is in process of publication. Unfortunately, the Ameri­ can Mesozoic and Cenozoic Ostracoda, although numerous, are not so well known, and, in spite of some excellent contributions to their study by several younger men in recent years, an enormous amount of work still remains incomplete. Such work is complicated by the fact that the post- Paleozoic ostracods were apparently wide rovers of the ancient seas, so that undoubtedly many species will be found common to the several con­ tinents. In Europe, many large monographs on Mesozoic and Cenozoic Ostracoda have been published, accompanied, for the most part, by such poor or diagrammatic illustrations that the types or topotypes must be refigured before accurate specific identifications in America can be made with confidence. The higher Crustacea, the Malacostraca, offer another interesting, although difficult, field of study. With the exception of the decapods so ably investigated by Miss Eathbun, this superorder has re­ ceived little attention for more than a generation. Work is especially needed in the post-Cambrian phyllocarids. With this brief review of some of the studies which are still necessary among the invertebrate fossils, it is fitting that we pay some attention, in closing, to the research work still to be done from a stratigraphic stand­

Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/44/2/265/3414963/BUL44_2-0265.pdf by guest on 30 September 2021 CURRENT PROBLEMS OF INVERTEBRATE PALEONTOLOGY 285

point. To review the needs throughout the geological column, even briefly, would require much more time than is at our disposal. If we restrict ourselves to the Paleozoic, we still find many faunas which re­ quire careful study and description. In the Cambrian, in spite of the great works of Walcott, in which certain groups of organisms, such as the brachiopods and trilobites, have been studied in considerable detail, other elements of the fauna are often greatly in need of description or revision. In the Ozarkian and Canadian systems only a small portion of the species has been described, but investigations on the rest are well under way by members of the United States Geological Survey and the United States National Museum, whose collections contain the most com­ plete representation of these faunas. There is, perhaps, no system of the Paleozoic which has received more attention in proportion to its size than the Ordovician of North America, partly because of the wealth of well-preserved fossils afforded by it. The faunas of the standard sections in New York, Ohio, and Canada are fairly well known, but elsewhere, almost invariably, they are little known. Ordovician in our country exhibit their development in differ­ ent basins of deposition, with frequent changes in the contained life, bet­ ter perhaps than do those of any other system of geologic time. Certain regions, such as the Appalachian Yalley in Virginia and Tennessee, where such basins are well developed, contain large assemblages of fossils, most of which are still undescribed. For example, in this region the Chazyan is composed, in ascending order, of the Murfreesboro limestone, 300 feet thick; Mosheim limestone, 50 to 125 feet thick; the Lenoir limestone, 40 to 700 feet; the Holston marble, 350 feet; the Whitesburg limestone, 500 feet; the Athens shale, 4,000 feet; the Tellico formation, 1,500 feet, and the Ottosee shale, 2,600 feet. Throughout this great thickness, fossils are abundant at a number of zones, and, of the great faunas represented there, only a comparatively few species have been described. In other parts of the country, especially in Oklahoma and Nevada, this same inter­ val is represented by quite distinct and abundantly fossiliferous forma­ tions. In the course of his stratigraphic studies, Ulrich has devoted many years to the separation and tentative classification of the Chazyan fossils. Although about 200 species have been published, at least four times that number remain unknown to the scientific world. The Silurian system likewise affords many examples of regions where much faunal study is still necessary. These are in areas, such as the Southern Appalachians, far from the type sections, or in the Mississippi Valley, where various dolomites and other strata of this age do not afford

Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/44/2/265/3414963/BUL44_2-0265.pdf by guest on 30 September 2021 286 E. S. BASSLER----INVERTEBRATE PALEONTOLOGY IN AMERICA

the best preserved fossils. In the Devonian, the formations of various parts of the Mississippi Valley and Eocky Mountain region have many unstudied invertebrates. In the Mississippian and Pennsylvanian, brief mention may be made of the faunas of the Southern Appalachians and the regions west of the Eockies. ' In concluding, I may state my idea of the greatest need in American invertebrate paleontology today. It is for more careful work, prepared less hastily, and issued with more regard to its value to the workers of the future. Students young in the science would do well to copy the standard authorities, rather than branch out too independently at first. A student should not, as is often the case, attempt the description and illustration of an entire fauna for his first publication. It is obvious that close study and mastery of a single class, or part of a fauna, will be of more lasting value to the science. With the many advantages which they enjoy that were not possessed by their predecessors, the paleontolo­ gists of the future can and should do better work than has ever been done in the past. Let us hope that the Paleontological Society will foster, en­ courage, and aid its younger members in their efforts to raise the standards of their science on this continent.

Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/44/2/265/3414963/BUL44_2-0265.pdf by guest on 30 September 2021