Ancient Plants – Appendix III

APPENDIX III
LITERATURE

A short list of a few of the more important papers and books to which a student should refer. The innumerable papers of the specialists will be found cited in these, so that, as they would be read only by advanced students, there is no attempt to catalog them here.

Carruthers, W., “On Fossil Cycadean Stems from the Secondary Rocks of Britain,” published in the Transactions of the Linnean Society, vol. xxvi, 1870.

*Geikie, A., A Text-Book of Geology, vols. i and ii, London, 1903.

Grand’Eury, C., “Flore Carbonifère du département de la Loire et du center de la France”, published in the Mémoirs de l’Académie des Sciences, Paris, vol. xxiv, 1877.

*Kidston, R., Catalogue of the Palæozoic Plants in the Department of Geology and Palæontology of the British Museum, London, 1886.

*Lapworth, C., An Intermediate Text-Book of Geology, twelfth edition, London, 1888.

Laurent, L., “Les Progrès de la paléobotanique angiospermique dans la dernière decade”, Progressus Rei Botanicæ, vol. i, Heft 2, pp. 319-68, Jena, 1907.

Lindley, J., and Hutton, W., The Fossil Flora of Great Britain, 3 vols., published in London, 1831-7.

Lyell, C., Principles of Geology and The Student’s Lyell, edited by J. W. Judd, London, 1896.

Oliver, F. W., and Scott, D. H., “On the Structure of the Palæozoic Seed, Lagenostoma Lomaxi”, published in the Transactions of the Royal Society, series B, vol. cxcvii, London, 1904.

Renault, B., Cours de Botanique fossile, Paris, 1882, 4 vols.

Renault, B., Bassin Houiller et Permien d’Autun et d’Epinac, Atlas and Text, 1893-6, Paris.

*Scott, D. H., Studies in Fossil Botany, London, second edition, 1909.

Scott, D. H., “On the Structure and Affinities of Fossil Plants from the Palæozoic Rocks. On Cheirostrobus, a New Type of Fossil Cone from the Lower Carboniferous Strata.” Published in the Philosophical Transactions of the Royal Society, vol. clxxxix, B, 1897.

*Seward, A. C., Fossil Plants, vol. i, Cambridge, 1898.

Seward, A. C., Catalogue of the Mesozoic Plants in the Department of Geology of the British Museum, Parts I and II, London, 1894-5.

*Solms-Laubach, Graf zu, Fossil Botany (translation from the German), Oxford, 1891.

Stopes, M. C., and Watson, D. M. S., “On the Structure and Affinities of the Calcareous Concretions known as ‘Coal Balls’”, published in the Philosophical Transactions of the Royal Society, vol. cc.

*Stopes, M. C., The Study of Plant Life for Young People, London, 1906.

*Watts, W. W., Geology for Beginners, London, 1905 (second edition).

Wieland, G. R., American Fossil Cycads, Carnegie Institute, 1906.

Williamson, W. C., A whole series of publications in the Philosophical Transactions of the Royal Society from 1871 to 1891, and three later ones jointly with Dr. Scott; the series entitled “On the Organization of the Fossil Plants of the Coal Measures”, Memoir I, II, &c.

Zeiller, R., Éléments de Paléobotanique, Paris, 1900.

*Zittel, K., Handbuch der Palæontologie, vol. ii; Palæophytologie, by Schimper & Schenk, München and Leipzig, 1900.

Those marked * would be found the most useful for one beginning the subject.

Ancient Plants – Appendix II

APPENDIX II
TREATMENT OF SPECIMENS

1. The commonest form in which fossils are collected is that which has been described as impression material. In many cases these will need no further attention after the block of stone on which they lie has been chipped into shape.

In chipping a block down to the size required it is best to hold it freely in the left hand, protecting the actual specimen with the palm where possible, and taking the surplus edges away by means of short sharp blows from the hammer, striking so that only small pieces come away with each blow. For delicate specimens it is wise to leave a good margin of the matrix round the specimen, and to do the final clearing with a thin-bladed penknife, taking away small flakes of the stone with delicate taps on the handle of the knife.

Specimens from fine sandstones, shales, and limestones are usually thoroughly hard and resistant, and are then much better if left without treatment; by varnishing and polishing them many amateur collectors spoil their specimens, for a coat of shiny varnish often conceals the details of the fossil itself. Impressions of plants on friable shales, on the other hand, or those which have a tendency to peel off as they dry, will require some treatment. In such cases the best substance to use is a dilute solution of size, in which the specimen should soak for a short period while the liquid is warm (not hot), after which it should be slightly drained and the size allowed to dry in. The congealed substance then holds the plant film on to the rock surface and prevents the rock from crumbling away, while it is almost invisible and does not spoil the plant with any excessive glaze.

2. For specimens of casts the same treatment generally applies, though they are more apt to separate completely from the matrix after one or two sharp blows, and thus save one the work of picking out the details of their structure.

3. Those blocks which contain petrifactions, and can therefore be made to show microscopic details, will require much more treatment. In some cases mere polishing reveals much of the structure:such, for instance, were the “Staarsteine” of the German lapidaries, where the axis and rootlets of a fossil like a treefern show their very characteristic pattern distinctly.

As a rule, however, it is better, and for any detailed work it is essential, to cut thin sections transversely across and longitudinally through the axis of the specimen and to grind them down till they are so transparent that they can be studied through the microscope. The cutting can be done on a lapidary’s wheel, where a revolving metal disc set with diamond powder acts as a knife. The comparatively thin slice thus obtained is fastened on to glass by means of hard Canada balsam, and rubbed down with carborundum powder till it is thin enough.

The process, however, is very slow, and an amateur cannot get good results without spending a large amount of time and patience over the work which would be better spent over the study of the plant structures themselves. Therefore it is usually more economical to send specimens to be cut by a professional, if they are good enough to be worth cutting at all, though it is often advisable to cut through an unpromising block to see whether its preservation is such as would justify the expense.

In the case of true “coal balls” much can be seen on the cut surface of a block, particularly if it be washed for a minute in dilute hydrochloric acid and then in water, and then dried thoroughly. The acid acts on the carbonates of which the stone is largely composed, and the treatment accentuates the black-and-white contrast in the petrified tissues. After lying about for a few months the sharpness of the surface gets rubbed off, as the acid eats it into very delicate irregularities which break and form a smearing powder; but in such a case all that is needed to bring back the original perfection of definition is a quick wash of dilute acid and water. If the specimens are not rubbed at all the surface is practically permanent. Blocks so treated reveal a remarkable amount of detail when examined with a strong hand lens, and form very valuable museum specimens.

The microscope slides should be covered with glass slips (as they would naturally be if purchased), and studied under the microscope as sections of living plants would be.

Microscopic slides of fossils make excellent museum specimens when mounted as transparencies against a window or strong light, when a magnifying glass will reveal all but the last minutiæ of their structure.

4. Labelling and numbering of specimens is very important, even if the collection be but a small one. As well as the paper label giving full details, there should be a reference number on every specimen itself. On the microscope slides this can be cut with a diamond pencil, and on the stones sealing wax dissolved in alcohol painted on with a brush is perhaps the best medium. On light-coloured close-textured stones ink is good, and when quite dry can even be washed without blurring.

The importance of marking the stone itself will be brought home to one on going through an old collection where the paper labels have peeled or rubbed off, or their wording been obliterated by age or mould.

A notebook should be kept in which the numbers are entered, with a note of all the items on the paper label, and any additional details of interest.

Ancient Plants – Appendix I

APPENDIX I
LIST OF REQUIREMENTS FOR A COLLECTING EXPEDITION

In order to obtain the best possible results from an expedition, it is well to go fossil hunting in a party of two, four, or six persons. Large parties tend to split up into detachments, or to waste time in trying to keep together.

Each individual should have strong suitable clothes, with as many pockets arranged in them as possible. The weight of the stones can thus be distributed over the body, and is not felt so much as if they were all carried in a knapsack. Each collector should also provide himself with:

A satchel or knapsack, preferably of leather or strong canvas, but not of large size, for when the space is limited selection of the specimens is likely to be made carefully.

One or two hammers. If only one is carried, it should be of a fair size with a square head and strong straight edge.

One chisel, entirely of metal, and with a strong straight cutting edge.

Soft paper to wrap up the more delicate fossils, in order to prevent them from scraping each other’s surfaces; and one or two small cardboard boxes for very fragile specimens.

A map of the district (preferably geologically colored). Localities should be noted in pencil on this, indicating the exact spot of finds. For general work the one-inch survey map suffices, but for detailed work it is necessary to have the six-inch maps of important districts.

A small notebook. Few notes are needed, but those few must be taken on the spot to be reliable.

A pencil or fountain pen, preferably both.

A penknife, which, among other things, will be found useful for working out very delicate fossils.

Ancient Plants – Preface and TOC

 

ANCIENT PLANTS

cover

front

Photo. of the specimen in Manchester Museum.
THE STUMP OF A LEPIDODENDRON FROM THE COAL MEASURES

ANCIENT PLANTS

BEING A SIMPLE ACCOUNT OF THE PAST VEGETATION OF THE EARTH AND OF THE RECENT IMPORTANT DISCOVERIES MADE IN THIS REALM OF NATURE STUDY

BY

MARIE C. STOPES, D.Sc., Ph.D., F.L.S.

Lecturer in Fossil Botany, Manchester University

Author of “The Study of Plant Life for Young People”

LONDON

BLACKIE & SON, Limited, 50 OLD BAILEY, E.C.

GLASGOW AND BOMBAY

1910

Preface

The number and the importance of the discoveries which have been made in the course of the last five or six years in the realm of Fossil Botany have largely altered the aspect of the subject and greatly widened its horizon. Until comparatively recent times the rather narrow outlook and the technical difficulties of the study made it one which could only be appreciated by specialists. This has been gradually changed, owing to the detailed anatomical work which it was found possible to do on the carboniferous plants, and which proved to be of great botanical importance. About ten years ago textbooks in English were written, and the subject was included in the work of the honours students of Botany at the Universities. To-day the important bearing of the results of this branch of Science on several others, as well as its intrinsic value, is so much greater, that anyone who is at all acquainted with general science, and more particularly with Botany and Geology, must find much to interest him in it.

There is no book in the English language which places this really attractive subject before the non-specialist, and to do so is the aim of the present volume. The two excellent English books which we possess, viz. Seward’s Fossil Plants (of which the first volume only has appeared, and that ten years ago) and Scott’s Studies in Fossil Botany, are ideal for advanced University students. But they are written for students who are supposed to have a previous knowledge of technical botany, and prove very hard or impossible reading for those who are merely acquainted with Science in a general way, or for less advanced students.

The inclusion of fossil types in the South Kensington syllabus for Botany indicates the increasing importance attached to palæobotany, and as vital facts about several of those types are not to be found in a simply written book, the students preparing for the examination must find some difficulty in getting their information. Furthermore, Scott’s book, the only up-to-date one, does not give a complete survey of the subject, but just selects the more important families to describe in detail.

Hence the present book was attempted for the double purpose of presenting the most interesting discoveries and general conclusions of recent years, and bringing together the subject as a whole.

The mass of information which has been collected about fossil plants is now enormous, and the greatest difficulty in writing this little book has been the necessity of eliminating much that is of great interest. The author awaits with fear and trembling the criticisms of specialists, who will probably find that many things considered by them as particularly interesting or essential have been left out. It is hoped that they will bear in mind the scope and aim of the book. I try to present only the structure raised on the foundation of the accumulated details of specialists’ work, and not to demonstrate brick by brick the exposed foundation.

Though the book is not written specially for them, it is probable that University students may find it useful as a general survey of the whole subject, for there is much in it that can only be learned otherwise by reference to innumerable original monographs.

In writing this book all possible sources of information have been consulted, and though Scott’s Studies naturally formed the foundation of some of the chapters on Pteridophytes, the authorities for all the general part and the recent discoveries are the numerous memoirs published by many different learned societies here and abroad.

As these pages are primarily for the use of those who have no very technical preliminary training, the simplest language possible which is consistent with a concise style has always been adopted. The necessary technical terms are either explained in the context or in the glossary at the end of the book. The list of the more important authorities makes no pretence of including all the references that might be consulted with advantage, but merely indicates the more important volumes and papers which anyone should read who wishes to follow up the subject.

All the illustrations are made for the book itself, and I am much obliged to Mr. D. M. S. Watson, B.Sc., for the microphotos of plant anatomy which adorn its pages. The figures and diagram are my own work.

This book is dedicated to college students, to the senior pupils of good schools where the subject is beginning to find a place in the higher courses of Botany, but especially to all those who take an interest in plant evolution because it forms a thread in the web of life whose design they wish to trace.

M. C. STOPES.

December, 1909.

Contents

I. Introductory 
II. Various Kinds of Fossil Plants 
III. Coal, the most Important of Plant Remains 
IV. The Seven Ages of Plant Life 
V. Stages in Plant Evolution 
VI. Minute Structure of Fossil Plants: Likenesses to Living Ones 
VII. Minute Structure of Fossil Plants: Differences from Living Ones 
VIII. Past Histories of Plant Families: Flowering Plants 
IX. Past Histories of Plant Families: Higher Gymnosperms 
X. Past Histories of Plant Families: Bennettitales 
XI. Past Histories of Plant Families:The Cycads 
XII. Past Histories of Plant Families: Pteridosperms 
XIII. Past Histories of Plant Families:The Ferns 
XIV. Past Histories of Plant Families:The Lycopods 
XV. Past Histories of Plant Families:The Horsetails 
XVI. Past Histories of Plant Families: Sphenophyllales 
XVII. Past Histories of Plant Families:The Lower Plants 
XVIII. Fossil Plants as Records of Ancient Countries 
XIX. Conclusion
APPENDIX
I. List of Requirements for a Collecting Expedition
II. Treatment of Specimens
III. Literature
Glossary