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I896

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y?;<

CONTENTS.

GENERAL.

PAGE

African Grass Fires and their Effects. By G. F. Scott Elliott, M.A. 77

The Past, Present, and Future Water Supply of London. By E.

Frankland, F.R.S. 163

Gold Extraction Processes. By T. K. Rose, D.Sc, Assistant Assayer

of the Royal Mint ------- 484

ANIMAL MORPHOLOGY.

The Morphology of the Mollusca. By. W. Garstang, M.A., Fellow

of Lincoln College, Oxford 38

The Present Position of the Cell Theory, By G. C. Bourne, M.A.,

Fellow of New College, Oxford - - -94,227,304

Some Recent Memoirs upon Oligochfeta. By F. E. Beddard,

M.A., F.R.S. 19°

ANTHROPOLOGY.

Pre-historic Man in the Eastern Mediterranean. By J. L. Myers,

Fellow of Magdalen College, Oxford - - 335

Selection in Man. By John Beddoe, M.D., LL.D., F.R.S. - - 384

BOTANY.

On Recent Advances in Vegetable Cytology. By J. Bretland Farmer,
M.A., Professor of Botany in the Royal College of Science,
London - ---------22

The Reserve Materials of Plants [Concluded). By J. Reynolds
Green, M.A., F.R.S., Professor of Botany to the Pharma-
ceutical Society, London ------ 60

The Stelar Theory : A History and a Criticism. By A. G. Tansley,

B.A. i33j 215

Ferns : Aposporous and Apogamous. By C. T. Druery, F.L.S. - 242

Insular Floras. By W. Botting Hemsley, F.R.S.- - - 286,374

CHEMISTRY AND PHYSICS.

The General Bearings of Magnetic Observations. By Captain Ettrick
W. Creak, R.N., F.R.S., Superintendent of Compasses to
the Admiralty - - - - - - - - - 81

Solid Solutions. By James Walker, Ph.D., D.Sc, Professor of

Chemistry in University College, Dundee - - - - 121

2 /Sf&

vi CONTENTS.

PAGE

Notes on Atomic Weights. By Alexander Scott, M.A., Jacksonian

Demonstrator in the University of Cambridge - 202

The Growth of our Knowledge of Helium. By J. Norman Lockyer,

C.B., F.R.S. --------- 249

Light and Electrification. By Oliver Lodge, F.R.S., Professor of

Physics in University College, Liverpool - - - - 417

Recent Values of the Magnetic Elements at the Principal Magnetic
Observatories of the World. By Charles Chree, M.A.,
Superintendent of Kew Observatory - - - - - 499

T

GEOLOGY, MINERALOGY AND PALAEONTOLOGY

The Graptolites. By J. E. Marr, M.A., F.R.S., Fellow of St. John's

College, Cambridge -------- 360

Recent Discoveries in Avian Palaeontology. By C. W. Andrews - 398
An Extinct Plant of Doubtful Affinity. By A. C. Seward, M.A.,

F.G.S., University Lecturer in Botany, Cambridge - 428

The Work of the Portuguese Geological Survey. By Philip Lake,

M. A., St. John's College, Cambridge- - 439

Petrology in America. By Alfred Harker, M. A., Fellow of St. John's

College, Cambridge- ------- 459

PATHOLOGY.

The Hereditary Transmission of Micro-organisms. By G. A. Buck-
master, M.D., Lecturer on Physiology at St. George's Hospital,

London ---------- 324

PHYSIOLOGY.

Ludwig and Modern Physiology. By J. Burdon Sanderson, M.D.,
F.R.S., Regius Professor of Physiology in the University of
Oxford ---------- 1

On Some Applications of the Theory of Osmotic Pressures to
Physiological Problems (Part II.). By E. H. Starling, M.D.,
Lecturer on Physiology at Guy's Hospital, London - - 151

Iodine in the Animal Organism. By W. D. Halliburton, M.D.,

F.R.S., Professor of Physiology in King's College, London - 454

APPENDIX I.
Notices of Books, - - - - - - 1, xi, xxi, xxxi, xli

APPENDIX II.
Titles of Chemical Papers, - iv, xv, xxv, xxxm, xlii, xlvii

ALPHABETICAL LIST OF AUTHORS.

PAGE

Andrews, C W. Recent Discoveries in Avian Palaeontology - 398

Beddard, F. E. Some Recent Memoirs upon Oligochaeta - 190

Beddoe, John. Selection in Man - 384

Bourne, G. C. The Present Position of the Cell Theory 94, 227, 304
Buckmaster, G. A. The Hereditary Transmission of Micro-
organisms - - - - - - - ~324

Chree, Charles. Recent Values of the Magnetic Elements - - 499
Creak, Captain Ettrick. The General Bearings of Magnetic Observa-
tions ___-__--- 81
Druery, C. T. Ferns : Aposporous and Apogamous - - 242
Farmer, J. B. On Recent Advances in Vegetable Cytology - - 22
Frankland, E. The Past, Present and Future Water Supply of

London ------- 163

Garstang, W. The Morphology of the Mollusca - 38

Green, J. Reynolds. The Reserve Materials of Plants - 60

Halliburton, W. D. Iodine in the Animal Organism - 454

Harker, Alfred. Petrology in America - - 459
Hemsley, W. Botting. Insular Floras - - - 286, 374

Lake, Philip. The Work of the Portuguese Geological Survey 439

Lockyer, J. Norman. The Growth of our Knowledge of Helium - 249

Lodge, Oliver. Light and Electrification - - - - - 417

Marr, J. E. The Graptolites ------ 360

Myers, J. L. Prehistoric Man in the Eastern Mediterranean - 335

Rose, T. R. Gold Extraction Processes ----- 484

Sanderson, J. Burdon. Ludwig and Modern Physiology - - 1

Scott, Alexander. Notes on Atomic Weights ... - 202

Scott-Elliott, G. F. African Grass Fires and their Effects - - 77

Seward, A. C. An Extinct Plant of Doubtful Affinity - 428
Starling, E. H. On some Applications of the Theory of Osmotic

Pressures to Physiological Problems - - - - - 151

Tansley, A. G. The Stellar Theory - 133,215

Walker, James. Solid Solutions - - - - - - - 121

l-\\

Btimce progress

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No. 25.

March, 1896.

Vol. V.

LUDWIG AND MODERN PHYSIOLOGY.1

I. INTRODUCTION.

THE death of any discoverer — of any one who has
added largely to the sum of human knowledge —
affords a reason for inquiring what his work was and how
he accomplished it. This inquiry has interest even when
the work has been completed in a few years and has been
limited to a single line of investigation — much more when
the life has been associated with the origin and develop-
ment of a new science and has extended over half a
century.

The Science of Physiology as we know it came into
existence fifty years ago with the beginning of the active life
of Ludwig, in the same sense that the other great branch of
Biology, the Science of Living Beings (Ontology), as we
now know it, came into existence with the appearance of the
" Origin of Species ". In the order of time Physiology had
the advantage, for the new Physiology was accepted some
ten years before the Darwinian epoch. Notwithstanding, the
content of the science is relatively so unfamiliar, that before
entering: on the discussion of the life and work of the man
who, as I shall endeavour to show, had a larger share in
founding it than any of his contemporaries, it is necessary
to define its limits and its relations to other branches of
knowledge.

1 Founded upon a lecture delivered at the Royal Institution, Jan.
24, 1896.

2 SCIENCE PROGRESS.

The word Physiology has in modern times changed its
meaning. It once comprehended the whole knowledge of
Nature. Now it is the name for one of the two Divisions
of the Science of Life. In the progress of investigation
the study of that Science has inevitably divided itself into
two : Ontology, the Science of Living Beings ; Physiology,
the Science of Living Processes, and thus, inasmuch as
Life consist in processes, of Life itself. Both strive to
understand the complicated relations and endless varieties
which present themselves in living Nature, but by different
methods. Both refer to general principles, but they are of
a different nature.

To the Ontologist, the student of Living Beings, Plants
or Animals, the great fact of Evolution, namely, that from
the simplest beginning our own organism, no less than that
of every animal and plant with its infinite complication of
parts and powers, unfolds the plan of its existence — taken
with the observation that that small beginning was, in all
excepting the lowest forms, itself derived from two parents,
equally from each — is the basis from which his study and
knowledge of the world of living beings takes its departure.
For on these two facts — Evolution and Descent — the ex-
plorer of the forms, distribution and habits of animals and
plants has, since the Darwinian epoch, relied with an ever-
increasing certainty, and has found in them the explanation
of every phenomenon, the solution of every problem relating
to the subject of his inquiry. Nor could he wish for a more
secure basis. Whatever doubts or misgivings exist in the
minds of " non-biologists " in relation to it, may be attributed
partly to the association with the doctrine of Evolution of
questions which the true naturalist regards as transcen-
dental ; partly to the perversion or weakening of meaning
which the term has suffered in consequence of its introduc-
tion into the language of common life, and particularly to
the habit of applying it to any kind of progress or improve-
ment, anything which from small beginnings gradually
increases. But, provided that we limit the term to its
original sense — the Evolution of a living being from its
germ by a continuous, not a gradual process — there is no

LUDWIG AND MODERN PHYSIOLOGY. 3

conception which is more free from doubt either as to its
meaning or reality. It is inseparable from that of Life
itself, which is but the unfolding of a predestined harmony,
of a prearranged consensus and synergy of parts.

The other branch of Biology, that with which Ludwig's
name is associated, deals with the same facts in a different
way. While Ontology regards animals and plants as in-
dividuals and in relation to other individuals, Physiology
considers the processes themselves of which life is a complex.
This is the most obvious distinction, but it is subordinate to
the fundamental one, namely, that while Ontology has for
its basis laws which are in force only in its own province,
those of Evolution, Descent, and Adaptation, we Physiolo-
gists, while accepting these as true, found nothing upon them,
using them only for euristic purposes, i.e., as guides to dis-
covery, not for the purpose of explanation. Purposive Adapta-
tion, for example, serves as a clue, by which we are constantly
guided in our exploration of the tangled labyrinth of vital
processes. But when it becomes our business to explain
these processes — to say how they are brought about — we
refer them not to biological principles of any kind, but to
the Universal Laws of Nature. Hence it happens that
with reference to each of these processes, our inquiry is
rather how it occurs than why it occurs.

It has been well said that the Natural Sciences are the
children of necessity. Just as the other Natural Sciences
owed their origin to the necessity of acquiring that control
over the forces of Nature without which life would
scarcely be worth living, so Physiology arose out of human
suffering and the necessity of relieving it. It sprang indeed
out of Pathology. It was suffering that led us to know, as
regards our own bodies, that we had internal as well as
external organs, and probably one of the first generalisa-
tions which arose out of this knowledge was, that " if one
member suffer all the members suffer with it " — that all
work together for the good of the whole. In earlier times
the good which was thus indicated was associated in men's
minds with human welfare exclusively. But it was
eventually seen that Nature has no less consideration for

4 SCIENCE PROGRESS.

the welfare of those of her products which to us seem
hideous or mischievous, than for those which we regard
as most useful to man or most deserving of his admiration.
It thus became apparent that the good in question could not
be human exclusively, but as regards each animal its oivn
good — and that in the organised world the existence and
life of every species is brought into subordination to one
purpose — its own success in the struggle for existence.1

From what has preceded it may be readily understood
that in Physiology, Adaptation takes a more prominent
place than Evolution or Descent. In the prescientific
period adaptation was everything. The observation that
any structure or arrangement exhibited marks of adaptation
to a useful purpose was accepted not merely as a guide in
research, but as a full and final explanation. Of an organism
or organ which perfectly fulfilled, in its structure and work-
ing, the end of its existence, nothing further required to be
said or known. Physiologists of the present day recognise
as fully as their predecessors that perfection of contrivance
which displays itself in all living structures, the more ex-
quisitely the more minutely they are examined. No one,
for example, has written more emphatically on this point
than did Ludwig. In one of his discourses, after showing
how Nature exceeds the highest standard of human attain-
ment — how she fashions as it were out of nothing and with-
out tools, instruments of a perfection which the human
artificer cannot reach, though provided with every suitable
material — wood, brass, glass, india-rubber — he gives the
organ of sight as a signal example, referring among its

1 1 am aware that in thus stating the relation between adaptation and the
struggle for existence, I may seem to be reversing the order followed by
Mr. Darwin, inasmuch as he regarded the survival of organisms which are
fittest for their place in Nature, and of parts which are fittest for their
place in the organism, as the agency by which adaptedness is brought about.
However this may be expressed it cannot be doubted that fitness is an
essential of organisms. Living beings are the only things in Nature which
by virtue of evolution and descent are able to adapt themselves to their
surroundings. It is therefore only so far as organism (with all its attri-
butes) is presupposed, that the dependence of adaptation on survival is
intelligible.

LUDWIG AND MODERN PHYSIOLOGY. 5

other perfections to the rapidity with which the eye can
be fixed on numerous objects in succession and the instan-
taneous and unconscious estimates which we are able to
form of the distances of objects, each estimate involving a
process of arithmetic which no calculating machine could
effect in the time.1 In another discourse — that given at
Leipzig when he entered on his professorship in 1865 — he re-
marks that when in our researches into the finer mechanism
of an organ we at last come to understand it, we are
humbled by the recognition " that the human inventor is
but a blunderer as compared with the unknown Master of
the animal creation ",2

Some readers will perhaps remember how one of the
most brilliant of philosophical writers, in a discourse to the
British Association delivered a quarter of a century ago,
averred on the authority of a great Physiologist that the
eye, regarded as an optical instrument, was so inferior a
production that if it were the work of a mechanician it
would be unsaleable. Without criticising or endeavouring
to explain this paradox, I may refer to it as having given
the countenance of a distinguished name to a misconception
which I know exists in the minds of many persons, to the
effect that the scientific Physiologist is more or less blind to
the evidence of design in creation. On the contrary, the
view taken by Ludwig, as expressed in the words I have
quoted, is that of all Physiologists. The disuse of the
teleological expressions which were formerly current does
not imply that the indications of contrivance are less ap-
preciated, for, on the contrary, we regard them as more
characteristic of organism as it presents itself to our obser-
vation than any other of its endowments. But, if I may

1 I summarise here from a very interesting lecture entitled " Leid und
Freude in der Naturforschung " published in the Gartenlaube (Nos. 22 and
23) in 1870.

2 The words translated in the above sentence are as follows : " Wenn
uns endlich die Palme gereicht wird, wenn wir ein Organ in seinem
Zuzammenhang begreifen, so wird unser stolzes Gattungsbewusstsein durch
die Erkenntniss niedergedruckt, dass der menschlicher Erfinder ein Stumper
gegen den unbekannten Meister der thierischen Schbpfung sei ".

6 SCIENCE PROGRESS.

be permitted to repeat what has been already said, we use
the evidences of adaptation differently. We found no ex-
planation on this or any other biological principle, but refer
all the phenomena by which these manifest themselves to
the simpler and more certain Physical Laws of the Universe.

Why must we take this position ? First, because it is a
general rule in investigations of all kinds to explain the
more complex by the more simple. The material Universe
is manifestly divided into two parts, the living and the non-
living. We may, if we like, take the living as our Norma,
and say to the Physicists, You must come to us for Laws,
you must account for the play of energies in universal nature
by referring them to Evolution, Descent, Adaptation. Or
we may take these words as true expressions of the mutual
relations between the phenomena and processes peculiar to
living beings, using for the explanation of the processes
themselves the same methods which we should employ if
we were engaged in the investigation of analogous pro-
cesses going on independently of life. Between these two
courses there seems to me to be no third alternative, unless
we suppose that there are two material Universes, one to
which the material of our bodies belongs, the other com-
prising everything that is not either plant or animal.

The second reason is a practical one. We should have
to go back to the time which I have ventured to call pre-
scientific, when the world of life and organisation was sup-
posed to be governed exclusively by its own Laws. The
work of the past fifty years has been done on the opposite
principle, and has brought light and clearness where there
was before obscurity and confusion. All this progress we
should have to repudiate, but this would not be all. We
should have to forego the prospect of future advance.
Whereas by holding on our present course, gradually pro-
ceeding from the more simple to the more complex, from
the physical to the vital, we may confidently look forward
to extending our knowledge considerably beyond its present
limits.

A no less brilliant writer than the one already referred
to, who is also no longer with us, asserted that mind was a

LUDWIG AND MODERN PHYSIOLOGY. y

secretion of the brain in the same sense that bile is a secretion
of the liver or urine that of the kidney ; and many people
have imagined this to be the necessary outcome of a too
mechanical way of looking at vital phenomena, and that
Physiologists, by a habit of adhering strictly to their own
method, have failed to see that the organism presents prob-
lems to which this method is not applicable, such, e.g., as
the origin of the organism itself, or the origin and develop-
ment in it of the mental faculty. The answer to this sug-
gestion is that these questions are approached by Physio-
logists only in so far as they are approachable. We are
well aware that our business is with the unknown knowable,
not with the transcendental. During the last twenty years
there has been a considerable forward movement in Physio-
logy in the psychological direction, partly dependent on
discoveries as to the localisation of the higher functions of
the nervous system, partly on the application of methods of
measurement to the concomitant phenomena of psychical
processes. And these researches have brought us to the
very edge of a region which cannot be explored by our
methods — where measurements of time or of space are no
longer possible.

In approaching this limit the Physiologist is liable to fall
into two mistakes — on the one hand, that of passing into
the transcendental without knowing it ; on the other, that
of assuming that what he does not know is not knowledge.
The first of these risks seems to me of little moment ; first,
because the limits of natural knowledge in the psychological
direction have been well defined by the best writers, as, e.g.,
by du Bois-Reymond in his well-known essay "On the
Limits of Natural Knowledge," but chiefly because the in-
vestigator who knows what he is about is arrested in limine
by the impossibility of applying the experimental method
to questions beyond its scope. The other mistake is chiefly
fallen into by careless thinkers, who, while they object to
the employment of intuition even in regions where intuition
is the only method by which anything can be learned,
attempt to describe and define mental processes in mechan-
ical terms, assigning to these terms meanings which science

8 SCIENCE PROGRESS.

does not recognise, and thus slide into a kind of speculation
which is as futile as it is unphilosophical.

II. LUDWIG AS INVESTIGATOR AND TEACHER.

The uneventful history of Ludwig's life — how early he
began his investigation of the anatomy and function of the
kidneys ; how he became just fifty years ago titular Pro-
fessor at Marburg, in the small University of his native
State, Hesse Cassel ; how in 1849 he removed to Zurich as
actual Professor and thereupon married ; how he was six
years later promoted to Vienna — has already been admirably
related in these pages by Dr. Stirling. In 1865, after
twenty years of professorial experience, but still in the
prime of life and, as it turned out, with thirty years of
activity still before him, he accepted the Chair of Physio-
logy at Leipzig. His invitation to that great University
was by far the most important occurrence in his life, for the
liberality of the Saxon Government, and particularly the
energetic support which he received from the enlightened
Minister v. Falkenstein, enabled him to accomplish for
Physiology what had never before been attempted on an
adequate scale. No sooner had he been appointed than
he set himself to create what was essential to the
progress of the Science — a great Observatory, arranged
not as a Museum, but much more like a physical and
chemical Laboratory, provided with all that was needed for
the application of exact methods of research to the investiga-
tion of the processes of Life. The idea which he had ever in
view, and which he carried into effect during the last thirty
years of his life with signal success, was to unite his life-
work as an investigator with the highest kind of teaching.
Even at Marburg and at Zurich he had begun to form a
School ; for already men nearly of his own age had rallied
round him. Attracted in the first instance by his early
discoveries, they were held by the force of his character,
and became permanently associated with him in his work
as his loyal friends and followers — in the highest sense his
scholars. If, therefore, we speak of Ludwig as one of the

LUDWIG AND MODERN PHYSIOLOGY. o,

greatest teachers of Science the world has seen, we
have in mind his relation to the men who ranged them-
selves under his leadership in the building up of the Science
of Physiology, without reference to his function as an
ordinary academical teacher.

Of this relation we can best judge by the careful perusal
of the numerous biographical memoirs which have appeared
since his death, more particularly those of Professor His1
(Leipzig), of Professor Kronecker2 (Bern), who was for
many years his coadjutor in the Institute, of Professor v.
Fick 3 (Wlirzburg), of Professor v. Kries * (Freiburg), of
Professor Mosso5 (Turin), of Professor Fano 6 (Florence),
of Professor Tigerstedt 7 (Upsala), of Professor Stirling s
in England. With the exception of Fick, whose relations with
Ludwig were of an earlier date, and of his colleague in the
Chair of Anatomy, all of these distinguished teachers were
at one time workers in the Leipzig Institute. All testify
their love and veneration for the master, and each contributes
some striking touches to the picture of his character.

All Ludwig's investigations were carried out with his
scholars. He possessed a wonderful faculty of setting each
man to work at a problem suited to his talent and previous
training, and this he carried into effect by associating him
with himself in some research which he had either in
progress or in view. During the early years of the Leip-
zig period, all the work done under his direction was
published in the well-known volumes of the Arbeiten, and

1 His. " Karl Ludwig und Karl Thiersch.'' Akademische Geddcht-
nissrede, Leipzig, 1S95.

2 Kronecker. "Carl Friedrich Wilhelm Ludwig." Berliner Klin,
Wochensch., 1895, No. 21.

3 A. Fick. " Karl Ludwig." Nachruf. Biographische Blatter, Berlin,
vol. i., pt. 3.

4 v. Kries. "Carl Ludwig." Freiburg, Bd. i., 1895.

5 Mosso. " Karl Ludwig." Die Nation, Berlin, Nos. 38, 39.

6 Fano. " Per Carlo Ludwig Commemorazione." Clinica Afodema,
Florence, i., No. 7.

7 Tigerstedt. " Karl Ludwig." Denkrede. Biographische Blatter, Berlin,
vol. i., pt. 3.

8 Stirling. "Science Progress," vol. iv., No. 21.

io SCIENCE PROGRESS.

subsequently in the Archiv fur Anat. unci Physiologic of
du Bois-Reymoncl. Each " Arbeit ': of the laboratory
appeared in print under the name of the scholar who
operated with his master in its production, but the
scholar's part in the work done varied according to its
nature and his ability. Sometimes, as v. Kries says, he sat
on the window-sill while Ludwig with the efficient help of
his laboratory assistant Salvenmoser, did the whole of the
work. In all cases Ludwig not only formulated the
problem, but indicated the course to be followed in each
step of the investigation, calling the worker, of course, into
counsel. In the final working up of the results he always
took a principal part, and often wrote the whole paper. But
whether he did little or much, he handed over the whole
credit of the performance to his coadjutor. This method of
publication has no doubt the disadvantage that it leaves
it uncertain what part each had taken ; but it is to be
remembered that this drawback is unavoidable whenever
master and scholar work together, and is outweighed by the
many advantages which arise from this mode of co-opera-
tion. The instances in which any uncertainty can exist in
relation to the real authorship of the Leipzig work are
exceptional. The well-informed reader does not need to
be told that Mosso or Schmidt, Brunton or Gaskell, Stirling
or Wooldridge were the authors of their papers in a sense
very different from that in which the term could be applied
to some others of Ludwig's pupils. On the whole the plan
must be judged of by the results. It was by working with
his scholars that Ludwig trained them to work afterwards by
themselves ; and thereby accomplished so much more than
other great teachers have done.

I do not think that any of Ludwig's contemporaries
could be compared to him in respect of the wide range of
his researches. In a science distinguished from others by
the variety of its aims, he was equally at home in all
branches, and was equally master of all methods, for he
recognised that the most profound biological question can
only be solved by combining anatomical, physical and
and chemical inquiries. It was this consideration which led

LUDWIG AND MODERN PHYSIOLOGY. n

him in planning the Leipzig Institute to divide it into three
parts, experimental (in the more restricted sense), chemical
and histological. Well aware that it was impossible for a
man who is otherwise occupied to maintain his familiarity
with the technical details of Histology and Physiological
Chemistry, he placed these departments under the charge
of younger men capable of keeping them up to the rapidly
advancing standard of the time, his relations with his
coadjutors being such that he had no difficulty in retaining
his hold of the threads of the investigation to which these
special lines of inquiry were contributory.

It is scarcely necessary to say that as an experimenter
Ludwig was unapproachable. The skill with which he
carried out difficult and complicated operations, the care
with which he worked, his quickness of eye and certainty
of hand were qualities which he had in common with great
surgeons. In employing animals for experiment he strongly
objected to rough and ready methods, comparing them to
" firing a pistol into a clock to see how it works ". Every
experiment ought, he said, to be carefully planned and
meditated on beforehand, so as to accomplish its scientific
purpose and avoid the infliction of pain. To ensure this
he performed all operations himself, only rarely committing
the work to a skilled coadjutor.

His skill in anatomical work was equally remarkable.
It had been acquired in early days, and appeared throughout
his life to have given him very great pleasure, for Mosso
tells how, when occupying the room adjoining that in which
Ludwig was working as he usually did by himself, he heard
the outbursts of glee which accompanied each successful step
in some difficult anatomical investigation.

Let us now examine more fully the part which Ludwig
played in the revolution of ideas as to the nature of vital
processes which, as we have seen, took place in the middle
of the present century.

Although, as we shall see afterwards, there were many
men who, before Ludwig's time, investigated the phenomena
of life from the physical side, it was he and the contem-
poraries who were associated with him who first clearly

12 SCIENCE PROGRESS.

recognised the importance of the principle that vital pheno-
mena can only be understood by comparison with their physical
counterparts, and foresaw that in this principle the future of
Physiology was contained as in a nutshell. Feeling strongly
the fruitlessness and unscientific character of the doctrines
which were then current, they were eager to discover
chemical and physical relations in the processes of life.
In Ludwig's intellectual character this eagerness expressed
his dominant motive. Notwithstanding that his own re-
searches had in many instances proved that there are im-
portant functions and processes in the animal organism
which have no physical or chemical analogues, he never
swerved either from the principle or from the method
founded upon it.

Although Ludwig was strongly influenced by the rapid
progress which was being made in scientific discovery at
the time that he entered on his career, he derived little from
his immediate predecessors in his own science. He is
sometimes placed among the pupils of the great Comparative
Anatomist and Physiologist, J. Mliller. This, however, is a
manifest mistake, for Ludwig did not visit Berlin until 1847,
when Miiller was nearly at the end of his career. At that
time he had already published researches of the highest
value (those on the Mechanism of the Circulation and on the
Physiology of the Kidney), and had set forth the line in
which he intended to direct his investigations. The only
earlier Physiologist with whose work that of Ludwig can
be said to be in real continuity was E. H. Weber, whom he
succeeded at Leipzig, and strikingly resembled in his way
of working. For Weber, Ludwig expressed his veneration
more unreservedly than for any other man, excepting per-
haps Helmholtz, regarding his researches as the foundation
on which he himself desired to build. Of his colleagues at
Marburg he was indebted in the first place to the anatomist,
Professor Ludwig Fick, in whose department he began his
career as Prosector, and to whom he owed facilities without
which he could not have carried out his earlier researches ;
and in an even higher degree to the great chemist, R. W.
Bunsen, from whom he derived that training in the exact

LUDWIG AND MODERN PHYSIOLOGY. 13

sciences which was to be of such inestimable value to him
afterwards.

There is reason, however, to believe that, as so often
happens, Ludwig's scientific progress was much more in-
fluenced by his contemporaries than by his seniors. In
1847, as we learn on the one hand from du Bois-Reymond,
on the other from Ludwig himself, he visited Berlin for the
first time. This visit was an important one both for him-
self and for the future of Science, for he there met three
men of his own age, Helmholtz, du Bois-Reymond and
Brticke, who were destined to become his life-friends, all of
whom lived nearly as long as Ludwig himself, and attained
to the highest distinction. They all were full of the same
enthusiasm. As Ludwig said when speaking of this visit :
" We four imagined that we should constitute Physiology
on a chemico-physical foundation, and give it equal scientific
rank with Physics, but the task turned out to be much more
difficult than we anticipated ". These three young men,
who were devoted disciples of the great Anatomist, had the
advantage over their master in the better insight which
their training had given them into the fundamental prin-
ciples of scientific research. They had already gathered
around themselves a so-called "physical " school of Physio-
logy, and welcomed Ludwig on his arrival from Marburg
as one who had of his own initiative undertaken in his own
University das Befremngswerk aus dcm Vitalismus.

The determination to refer all vital phenomena to their
physical or chemical counterparts or analogues, which, as I
have said, was the dominant motive in Ludwio's char-
acter, was combined with another quality of mind which if
not equally influential was even more obviously displayed in
his mode of thinking and working. His first aim, even
before he sought for any explanation of a structure or of
a process, was to possess himself, by all means of observa-
tion at his disposal, of a complete objective conception of
all its relations. He regarded the faculty of vivid sensual
realisation (lebendige sinnliche Anschanung) as of special
value to the investigator of natural phenomena, and did his
best to cultivate it in those who worked with him in the

14 SCIENCE PROGRESS.

laboratory. In himself, this objective tendency (if I may
be permitted the use of a word which, if not correct, seems
to express what I mean) might be regarded as almost a
defect, for it made him indisposed to appreciate any sort of
knowledge which deals with the abstract. He had a
disinclination to philosophical speculation which almost
amounted to aversion, and, perhaps for a similar reason,
avoided the use of mathematical methods even in the
discussion of scientific questions which admitted of being
treated mathematically — contrasting in this respect with
his friend du Bois-Reymond, resembling Brlicke. But
as a teacher the quality was of immense use to him. His
power of vivid realisation was the substratum of that many-
sidedness which made him, irrespectively of his scientific
attainments, so attractive a personality.

I am not sure that it can be generally stated that a keen
scientific observer is able to appreciate the artistic aspects
of Nature. In Ludwig's case, however, there is reason to
think that aesthetic faculty was as developed as the power of
scientific insight. He was a skilful draughtsman but not
a musician ; both arts were, however, a source of enjoy-
ment to him. He was a regular frequenter of the Gewand-
kaus concerts, and it was his greatest pleasure to bring to-
gether gifted musicians in his house, where he played the
part of an intelligent and appreciative listener. Of painting
he knew more than of music, and was a connoisseur whose
opinion carried weight. It is related that he was so worried
by what he considered bad art, that after the redecoration
of the Gczvandhaus concert-room, he was for some time
deprived of his accustomed pleasure in listening to music.

Ludwig's social characteristics can only be touched on
here in so far as they serve to make intelligible his wonder-
ful influence as a teacher. Many of his pupils at Leipzig
have referred to the schbne Gemeinsamkeit which char-
acterised the life there. The harmonious relation which,
as a rule, subsisted between men of different education and
different nationalities, could not have been maintained had
not Ludwig possessed side by side with that inflexible
earnestness which he showed in all matters of work or

LUDWIG AND MODERN PHYSIOLOGY. 15

duty a certain youthfulness of disposition which made it
possible for men much younger than himself to accept his
friendship. This sympathetic geniality was, however, not
the only or even the chief reason why Ludwig's pupils were
the better for having known him. There were not a few
of them who for the first time in their lives came into
personal relation with a man who was utterly free from
selfish aims and vain ambitions, who was scrupulously
conscientious in all that he said and did, who was what he
seemed, and seemed what he was, and who had no other
aim than the advancement of his science, and in that ad-
vancement saw no other end than the increase of human
happiness. These qualities displayed themselves in Lud-
wig's daily active life in the laboratory, where he was to be
found whenever work of special interest was going on ; but
still more when, as happened on Sunday mornings, he was
"at home" in the library of the Institute — the corner room
in which he ordinarily worked. Many of his "scholars"
have put on record their recollections of these occasions, the
cordiality of the master's welcome, the wide range and
varied interest of his conversation, and the ready apprecia-
tion with which he seized on anything that was new or
original in the suggestions of those present. Few men
live as he did, " im Gaznen, Gtiten, Sckonen" and of those
still fewer know how to communicate out of their fulness to
others.

III. THE OLD AND THE NEW VITALISM.

Since the middle of the century the progress of Physio-
logy has been continuous. Each year has had its record,
and has brought with it new accessions to knowledge. In
one respect the rate of progress was more rapid at first than
it is now, for in an unexplored country discovery is relatively
easy. In another sense it was slower, for there are now
scores of investigators for every one that could be counted
in 1840 or 1850. Until recently there has been throughout
this period no tendency to revert to the old methods — no
new departure — no divergence from the principles which
Ludwig did so much to enforce and exemplify.

16 SCIENCE PROGRESS.

The wonderful revolution which the appearance of the
Origin of Species produced in the other branch of Biology,
promoted the progress of Physiology, by the new interest
which it gave to the study, not only of structure and de-
velopment, but of all other vital phenomena. It did not,
however, in any sensible degree affect our method or alter
the direction in which Physiologists had been working for
two decades. Its most obvious effect was to sever the two
subjects from each other. To the Darwinian epoch Com-
parative Anatomy and Physiology were united, but as the
new Ontology grew, it became evident that each had its own
problems and its own methods of dealing with them.

The old vitalism of the first half of the century is easily
explained. It was generally believed that, on the whole,
things went on in the living body as they do outside of
it, but when a difficulty arose in so explaining them the
Physiologist was ready at once to call in the aid of a
" vital force' '. It must not, however, be forgotten that, as I
have already indicated, there were great teachers (such,
for example, as Sharpey and Allen Thomson in England,
Magendie in France, Weber in Germany) who discarded
all vitalistic theories, and concerned themselves only with
the study of the time- and place-relations of phenomena ;
men who were before their time in insight, and were only
hindered in their application of chemical and physical prin-
ciples to the interpretation of the processes of life by the
circumstance that chemical and physical knowledge was in
itself too little advanced. Comparison was impossible, for
the standards were not forthcoming.

Vitalism in its original form gave way to the rapid ad-
vance of knowledge as to the correlation of the physical
sciences which took place in the forties. Of the. many
writers and thinkers who contributed to that result, J. R.
Mayer and Helmholtz did so most directly, for the con-
tribution of the former to the establishment of the Doctrine
of the Conservation of Energy had physiological considera-
tions for its point of departure ; and Helmholtz, at the time
he wrote the Erhaltung der Kraft, was still a Physiolo-
gist. Consequently when Ludwig's celebrated Lehrbuch

LUDWIG AND MODERN PHYSIOLOGY. 17

came out in 1852, the book which gave the coup de grace to
vitalism in the old sense of the word, his method of setting
forth the relations of vital phenomena by comparison with
their physical or chemical counterparts, and his assertion that
it was the task of Physiology to make out their necessary
dependence on elementary conditions, although in violent
contrast with current doctrine, were in no way surprising to
those who were acquainted with the then recent progress
of research. Ludwig's teaching was indeed no more than
a general application of principles which had already been
applied in particular instances.

The proof of the non-existence of a special " vital force "
lies in the demonstration of the adequacy of the known
sources of energy in the organism to account for the actual
day by day expenditure of heat and work — in other words,
on the possibility of setting forth an energy balance sheet in
which the quantity of food which enters the body in a given
period (hour or day) is balanced by an exactly correspond-
ing amount of heat produced or external work done. It is
interesting to remember that the work necessary for
preparing such a balance sheet (which Mayer had attempted,
but, from want of sufficient data, failed in) was begun
thirty years ago in the laboratory of the Royal Institution
by the Foreign Secretary of the Royal Society. But the
determinations made by Dr. Frankland related to one side of
the balance sheet, that of income. By his researches in 1 866
he gave Physiologists for the first time reliable information
as to the heat value {i.e., the amount of heat yielded by the
combustion) of different constituents of food. It still re-
mained to apply methods of exact measurement to the
expenditure side of the account. Helmholtz had estimated
this, as regards man, as best he might, but the technical
difficulties of measuring the expenditure of heat of the
animal body appeared until lately to be almost insuperable.
Now that it has been at last successfully accomplished, we
have the experimental proof that in the process of life there
is no production or disappearance of energy. It may be
said that it was unnecessary to prove what no scientifically

sane man doubted. There are, however, reasons why it is

2

18 SCIENCE PROGRESS.

of importance to have objective evidence that food is the
sole and adequate source of the energy which we day by
day or hour by hour disengage, whether in the form of heat
or external work.

In the opening paragraph of this section it was observed
that until recently there had been no tendency to revive the
vitalistic notion of two generations ago. In introducing the
words in italics I referred to the existence at the present
time in Germany of a sort of reaction, which under the
term " Neovitalismus " has attracted some attention — -so
much indeed that at the Versani7nlung Deutscher Natur-
forscher at Ltibeck last September, it was the subject of
one of the general addresses. The author of this address,
Prof. Rindfleisch, was, I believe, the inventor of the word ;
but the origin of the movement is usually traced to a work
on Physiological Chemistry which an excellent translation
by the late Dr. Wooldridge has made familiar to English
students. The author of this work owes it to the language
he employs in the introduction on " Mechanism and
Vitalism," if his position has been misunderstood, for in
that introduction he distinctly ranges himself on the vital-
istic side. As, however, his vitalism is of such a kind as
not to influence his method of dealing with actual problems,
it is only in so far of consequence as it may affect the reader.
For my own part I feel grateful to Professor Bange for
having produced an interesting and readable book on a dry
subject, even though that interest may be partly due to the
introduction into the discussion of a question which, as he
presents it, is more speculative than scientific.

As regards other physiological writers to whom vitalistic
tendencies have been attributed, it is to be observed that
none of them have even suggested that the doctrine of a
"vital force" in its old sense should be revived. Their
contention amounts to little more than this, that in certain
recent instances improved methods of research appear to
have shown that processes at first regarded as entirely
physical or chemical do not conform so precisely as they
were expected to do to chemical and physical laws. As
these instances are all essentially analogous, reference to
one will serve to explain the bearing of the rest.

LUDWIG AND MODERN PHYSIOLOGY. 19

Those who have any acquaintance with the structure of
the animal body will know that there exists in the higher
animals, in addition to the system of veins by which the
blood is brought back from all parts to the heart, another
less considerable system of branched tubes, the lymphatics,
by which, if one may so express it, the leakage of the blood-
vessels is collected. Now, without inquiring into the why
of this system, Ludwig and his pupils made and continued
for many years elaborate investigations which were for long
the chief sources of our knowledge, their general result
being that the efficient cause of the movement of the lymph,
like that of the blood, was mechanical. At the Berlin Con-
gress in 1890 new observations by Professor Heidenhain of
Breslau made it appear that under certain conditions the
process of lymph formation does not go on in strict accord-
ance with the physical laws by which leakage through
membranes is regulated, the experimental results being of
so unequivocal a kind that, even had they not been con-
firmed, they must have been received without hesitation.
How is such a case as this to be met? The "Neovitalists "
answer promptly by reminding us that there are cells, i.e.,
living individuals, placed at the inlets of the system of
drainage without which it would not work, that these let in
less or more liquid according to circumstances, and that in
doing so they act in obedience, not to physical laws, but to
vital ones — to internal laws which are special to themselves.

Now, it is perfectly true that living cells, like working
bees, are both the architects of the hive and the sources of
its activity, but if we ask how honey is made it is no answer
to say that the bees make it. We do not require to be told
that cells have to do with the making of lymph as with
every process in the animal organism, but what we want to
know is how they work, and to this we shall never get an
answer so long as we content ourselves with merely ex-
plaining one unknown thing by another. The action of
cells must be explained, if at all, by the same method of
comparison with physical or chemical analogues that we
employ in the investigation of organs.

Since 1890 the problem of lymph formation has been

20 SCIENCE PROGRESS.

attacked by a number of able workers, among others here
in London, by Dr. Starling of Guy's Hospital, who, by
sedulously studying the conditions under which the dis-
crepancies between the actual and the expected have arisen,
has succeeded in untying several knots. In reference to
the whole subject, it is to be noticed that the process by
which difficulties are brought into view is the same as that
by which they are eliminated. It is one and the same
method throughout, by which step by step, knowledge per-
fects itself — at one time by discovering errors, at another
by correcting them ; and if at certain stages in this pro-
gress difficulties seem insuperable, we can gain nothing by
calling in, even provisionally, the aid of any sort of Eidolon,
whether "cell," "protoplasm" or internal principle.

It thus appears to be doubtful whether any of the
biological writers who have recently professed vitalistic
tendencies are in reality vitalists. The only exception
that I know is to be found in the writings of a well-
known morphologist, Dr. Hans Driesch,1 who has been
led by his researches on what is now called the Me-
chanics of Evolution to revert to the fundamental con-
ception of vitalism, that the laws which govern vital
processes are not physical, but biological — that is, peculiar
to the living organism, and limited thereto in their
operation. Dr. Driesch's researches as to the modifi-
cations which can be produced by mechanical inter-
ference in the early stages of the process of ontogenesis
have enforced upon him considerations which he evidently
regards as new, though they are familiar enough to Physio-
logists. He recognises that although by the observation of
the successive stages in the ontogenetic process, one may
arrive at a perfect knowledge of the relation of these stages
to each other, this leaves the efficient causes of the develop-
ment unexplained [fukrt nicht zu einem Erkenntniss ihrer
bewirkenden Ursacheii)- — it does not teach us why one

1 Driesch. " Entwicklungsmechanische Studien " : a series of ten
Papers, of which the first six appeared in the Zeitsch. /. w. Zoologie, vols,
liii. and lv. ; the rest in the Mittheihingen of the Naples Station.

LUDWIG AND MODERN PHYSIOLOGY. 21

form springs out of another. This brings him at once face
to face with a momentous question. He has to encounter
three possibilities — he may either join the camp of the
biological agnostics and say with du Bois-Reymond, "ignora-
mus et ignorabimus" or be content to work on in the hope
that the physical laws that underlie and explain organic
Evolution may sooner or later be discovered, or he may
seek for some hitherto hidden Law of Organism of which
the known facts of Ontogenesis are the expression, and
which, if accepted as a Law of Nature, would explain every-
thing. Of the three alternatives Driesch prefers the last,
which is equivalent to declaring himself an out and out
vitalist. He trusts by means of his experimental investiga-
tions of the Mechanics of Evolution to arrive at " elementary
conceptions" on which by "mathematical deduction"1 a
complete theory of Evolution may be founded.

If this anticipation could be realised, if we could con-
struct with the aid of those new Principia the ontogeny of
a single living being, the question whether such a result
was or was not inconsistent with the uniformity of Nature,
would sink into insignificance as compared with the
splendour of such a discovery.

But will such a discovery ever be made ? It seems to
me even more improbable than that of a physical theory
of organic evolution. It is satisfactory to reflect that the
opinion we may be led to entertain on this theoretical
question need not affect our estimate of the value ol Dr.
Driesch's fruitful experimental researches.

J. Burdon Sanderson.

1 " Elementarvorstellungen . . . die zwar mathematische Deduktion
aller Erscheinungen aus sich gestatten mochten." Driesch. " Beitrage
zur theoretischen Morphologic" Biol. Centralblatt, vol. xii., p. 539, 1892.

ON RECENT ADVANCES IN VEGETABLE

CYTOLOGY.

PART I.

DURING the last quarter of a century a considerable
change has passed over the aspect of biology,
especially in this country. It was formerly possible for a
man to be, fairly at any rate, well up in the two branches
of zoology and botany, but this is no longer possible,
regarded from our modern standpoint. Specialisation,
inevitable owing to the rapid advances which have been
everywhere made, has not only effected a practical
divorce between these two sciences, but the same disrupting
agency is operating continuously in each of them.

None the less is it true, however, that there are certain
features of fundamental importance which are shared alike
by animals and plants. This community of structure is
most clearly recognised within the limits of the individual
cells, and it is perhaps nowhere more impressively demon-
strated than in the remarkable similarity which exists
between the nuclear division as observed in animals and in
plants, — a similarity which may extend to the most minute
details.

The cell, using the word in its widest sense, is, as
Haeckel said long ago, emphatically the unit of life. For
though the several parts, such as nucleus and the cell-
protoplasm, which together constitute a cell, all possess
autonomy to a certain degree, it still remains true that it is
only when they operate jointly and in harmony that a suc-
cessful and "going concern," a living individual, is the
result. And since we have strong reasons for believing
that animals and plants represent the diverging limbs of a
stock traceable at the root to a common source, viz., lowly
unicellular organisms, it is obvious that the study of the cell,
of its structure and of the functions discharged by its
various parts, offers an immensely important, though it
may well be a very difficult, field for research.

RECENT ADVANCES IN VEGETABLE CYTOLOGY. 23

What, we may ask, is the essential structure of the
protoplasm, of the nucleus, and of those marvellous bodies,
the chromosomes, which reappear at every nuclear division ?
What is it that initiates the division of a cell or of its
nucleus, and why do some cells go through such complex
evolutions whilst others seem to adopt a relatively simple
course? What is it that determines that the descendants of
one cell shall develop differently from those of another, so
as to give rise to this or that tissue system ? Or again,
how is the unicellular condition of an infusorian compatible
with an intricate and often highly differentiated organisa-
tion ?

These and a host of other questions rise and confront
us on the very threshold of our inquiry, and the hints which
Nature has dropped for our guidance are at best only
obscure ones ; thus the position of the biological investigator
contrasts unfavourably with that of the chemist or physicist,
inasmuch as he is generally debarred, owing to the very
conditions of the bodies he is dealing with, from having
recourse to direct experiment ; Nature conducts the experi-
ments and he has to remain content with watching- the
result, analysing the factors and reconstructing the process
as best he can. Nevertheless there is, clearly, no funda-
mental distinction between the (so-called) observational
and experimental sciences.

It is, then, only by patient accumulation and careful
comparison of all the facts that even a proximate solution
of the difficulties before us can ever be reached. Much
has been done in collecting the data, and a good deal is
known both as to the structure of the cell and the phases
through which it passes during its existence. And fortu-
nately one generalisation is gradually emerging with in-
creasing clearness from beneath the ever-growing pile of
detail, and it promises to prove a guide of no small value,
namely, that in those processes which we have reason to
regard as fundamentally important there exists a surprising
degree of similarity between the structural elements of
animals on the one hand and of plants on the other. And
these points of similarity are now known to be so numerous

24 SCIENCE PROGRESS.

and so close that we are almost warranted in drawing the
conclusion that the measure of the resemblance will afford a
criterion as to the relative degree of importance to be
attached to this or that phenomenon of cell life.

It seems almost certain that this similarity is to be
interpreted as the result of the evolution along parallel
lines of a particular structural arrangement, or, to put it in
another way, as being the outcome of the continuous opera-
tion of similar forces upon an essentially similar proto-
plasmic structure. No doubt all the change manifested in
protoplasm is ultimately to be ascribed to the effects of
forces upon its own material substance ; the special point
of interest here lies in the similarity of the results. It
cannot be due to mere accident that the stages in the develop-
ment of the spermatozoa of a newt should bear a closer
resemblance to the corresponding divisions in the pollen-
mother-cell of a lily than they do to the rest of the tissue
cells in the body of the same newt.

In the present article it is not my purpose to attempt to
summarise the vast amount of detail which has accumulated
within recent years ; my aim is rather to try to indicate the
general directions in which the results seem to be tending,
and to point out the kind of evidence on which the current
views are based. And although I am here especially dealing
with the botanical aspect of the questions involved, it will
be clear from what has been already said that it will be
impossible, and certainly not desirable, to ignore the in-
vestigations which have been prosecuted by the zoologists.

And in order to make clear that which is to follow, it
may not be superfluous to recapitulate the general relations
of nucleus and cell protoplasm as commonly received at the
present time. The essential character of all cells, whether
animal or vegetable, and whether they exist as free inde-
pendent organisms, or whether they form more or less
highly differentiated colonies, consists in this, the association
of a nucleus with a certain amount of cell protoplasm (com-
monly called Cytoplasm, to distinguish it from the nuclear
protoplasm). And this is equally true, so far as we have
means of determining the question, in the case of those

RECENT ADVANCES IN VEGETABLE CYTOLOGY. 25

organisms in which we as yet have failed to recognise a de-
finite nuclear body, for there are reasons for believing that the
nuclear substance is in all cases really present, whether it
happens to be collected into a specialised mass or not. And
it should be remembered that the number of cells supposed
to possess what we may term a distributed or discrete
nucleus is becoming smaller as our means of investigations
improve. Thus according to Wager ( 1 ) even Bacteria
possess a true nucleus.

I am perfectly aware that attacks have recently been
made on the cell-theory as extended to explain the organisa-
tion (Whitman, Sedgwick) of animals, and that nobody
would assert the cell to the ultimate unit of living substance.
But neither of these propositions really affects, or is con-
cerned with, the point of view just now before us. We are
not here dealing with the wide questions connected with the
architecture of the organism as a whole, nor with the
equally difficult one, as to what constitutes the ultimate
units of living matter, rather we are content just now to
study the interaction of the parts which together are capable
of carrying on a continuous living existence, which form a
living individual, and these parts consist jointly of the
nucleus and its surrounding cytoplasm.1 The occurrence of
cell walls is a matter of no importance from a general stand-
point, although when present they may profoundly modify
the characters of the organism in which they are formed.
Many plants are known in which the protoplasm is only
delimited by a cell wall from the surrounding medium, while
the oftentimes huge protoplasmic mass suffers no internal
partitioning, although it contains a vast number of nuclei
distributed through it.

Sachs, with characteristic insight, long ago perceived
that the presence or absence of cell walls is a matter of
only secondary importance. Their sequence and arrange-
ment at the time of their first appearance can be predicted

1 The researches of Klebs, Acqua, and others have shown that although
protoplasm deprived of a nucleus may sometimes even assimilate food and
maintain life for a not inconsiderable period of time, it is incapable of
division.

26 SCIENCE PROGRESS.

from simple geometrical considerations quite independently
of the ultimate form which will be finally assumed as
the result of specialised growth. And in applying the word
Non-cellular to those plants in which partition walls do not
occur, he merely gives formal expression to the fact that
these anatomical structures are absent, although in other
respects the plants in question conform with those usually
called multicellular, and they are not at all to be regarded as
consisting of a single enlarged cell. In fact he has expressly
stated that non-cellular plants are really the equivalent of
multicellular organisms in which the formation of internal
cell walls does not occur. More recently he has introduced
the term Energid (2) to express the physiological individu-
ality of those units I have here continued to call cells, and
he thereby emphasises the fact of their real existence
whether any positive anatomical boundaries can be dis-
cerned between them or not.

It must however be clearly understood that in formulat-
ing the expression energid, Sachs lays especial stress on
the dynamical aspect of the relations existing between the
cytoplasm and the nucleus. But it will be admitted by most
people that a conception of force apart from the material
substance on or through which it acts, and by which its
operation becomes perceptible to the senses, belongs to the
domain of purely abstract ideas. We require to know far
more of the nature and structure of protoplasm before we
can usefully divorce our conceptions of force from our ex-
perience of matter in attempting to ascertain the nature
of those physiological causes of which all external form is
but the outward and visible sign. Sachs himself, however,
escapes the charge of vagueness, by restricting the applica-
tion of his expression so as to impose a territorial limit to
the sphere of influence mutually existing between each
nucleus and the surrounding cytoplasm. For him the word
Energid embodies the idea that the whole protoplasmic
region is partitioned into smaller provinces each dominated
by its own nucleus. And although it may be advantageous
for the seprovinces to be delimited from each other by cell
walls, permitting thereby a more complete independence to

RECENT ADVANCES IN VEGETABLE CYTOLOGY. 27

attach to each one severally, the existence of such well-
defined boundaries is by no means an indispensable condition
of great complexity of organisation. Caulerpa amongst the
algae imitates very closely the differentiated form of some
of the higher terrestrial plants, without however possessing
their corresponding internal structure. Its protoplasm is
bounded by an external wall only, and is not internally
partitioned. And yet the characters distinctive of the
energids in the leaf-like parts are assuredly different from
those of the energids which exist in the creeping stem or
rootlike fibres. A transition from the condition of Caulerpa
to that of the higher plants may be seen in Cladophora, in
which the filamentous body seems, at first sight, to be made
up of chains of cells, each of which stands in a definite
relation to the general symmetry of the branched plant ;
nevertheless, closer examination shows that each "cell" is
multi-nucleate, and really represents a federation of energids
which so act together as to constitute morphological units as
far as the external form of the plant as a whole is concerned.
Sachs' conception of the energid has been assailed by
some writers, and he has to some extent perhaps invited
criticism by formerly affixing a quasi-morphological, as well
as a physiological significance to the term. At first sight
it may seem difficult to justify its application in those cases
in which streaming movement happens to go on in certain
layers of the protoplasm, whilst the layer in which the
nuclei are embedded is at rest. It is obvious that if we
admit, as we can hardly avoid doing, that the nucleus does
really exert a directive action over a localised area, the
migratory protoplasm (assuming the movement to affect the
protoplasm, and not merely the granular bodies contained
in it) must be constantly coming within the range of
fresh centres of influence. It may perhaps be compared
to the case of a person passing from a region presided
over by one government into one under the jurisdic-
tion of another. Such a person would naturally be subjected
to changed conditions, without however affecting either his
own identity or that of the particular political centres through
which he may happen to travel.

28 SCIENCE PROGRESS.

Strasburger (3) has attempted to define more clearly the
position of the individual energid, by proposing to limit its
application to the nucleus together with a special part of the
cytoplasm which he calls Kinoplasm and which he regards
as the proximate seat of the effective manifestation of the
forces at work in the cell. He regards the nomadic
streaming protoplasm as being mainly charged with the
function of providing nourishment for the nucleus and
kinoplasm, and he distinguishes it by the special term of
Trophoplasm. Strasburger maintains this same distinction
between the active Kinoplasm and the nutritive tropho-
plasm in those cases in which the limits of the several
energids correspond with those of the individual cells ;
and in this he is logical enough, for we know that living
cells are not isolated from each other, but that protoplasmic
continuity exists between adjacent cells by means of pores
in the intervening walls. How far the distinction between
kinoplasm and trophoplasm is either justified by observa-
tion or demanded by theory is another matter altogether.

But although the conception of energids is a happy one,
as enabling us to distinguish discrete individualities in what
may at first sight appear to consist of a common structure,
it is not to be inferred that the individuals enjoy independ-
ence. The great merit of the idea lies in the fact that it
serves to narrow down, and hence to render more clearly
comprehensible, many important problems which call for a
solution before we can hope to grapple successfully with
the more advanced questions relating to those forces of a
still higher order which control and apparently direct the
development of the organism as a whole, or to put it in
another way, which determine the course of development
which the particular energids shall follow. Such control is
plainly apparent at every stage in the life of an organism.
Why does growth take place symmetrically so that the
energids, cells, or whatever we may choose to call them, so
act in unison as to produce a " body fitly joined together
and compacted by that which every joint supplieth, accord-
ing to the effectual working in the measure of every
part " ? Without some such assumption how is it

RECENT ADVANCES IN VEGETABLE CYTOLOGY. 29

possible to account for the fact that in certain embryos
which have been mutilated, the surviving cells are enabled
to so modify the course of their normal development as
to make good the loss, and thus to form a perfect, if
somewhat miniature organism ? For had there been no
mutilation the cells thus concerned would unquestion-
ably not have developed in the same way, but would have
fulfilled the allotted task of merely providing for the genesis
of their normal tissue products. Or again, why is it that
when a lizard's tail is broken off the general form of the
entire animal is once more reproduced, even though there
are important histological and structural (but probably not
functional) differences in the new tail as compared with
that of the original one (4) ?

When differentiation has so far become manifested in
an organism that the limits of the several energids are
coterminous with the cell walls, a considerable increase in
their degree of independence doubtless ensues, but it is, as
already stated, by no means absolute, and the examples just
quoted support the statement. Whether organisation is
the result of, or the factor which determines, the co-ordi-
nate action of the cells is a question which we may safely
leave to the future to decide. But perhaps it may be
permissible to compare the cell colony which forms the
organism to an isolated society in which the caste system
prevails. Each caste or cell group is predestined to dis-
charge certain definite offices in the state or the organism.
If some indispensable caste should become exterminated, it is
obvious that a differentiation and displacement must occur
amongst those which survive, and this differentiation
might either be readily complete, or it might only arise as
a reluctant concession to necessity, just as a willow twig
planted upside down in damp soil will form roots at this, its
upper, end ; though comparison with a twig planted with
its basal end in the ground will show how severe a tax the
unusual effort has proved.

It has already been said that an energid, and it might
also be added, a typical cell, consists essentially of a nucleus
and the protoplasm included within a certain area around

30 SCIENCE PROGRESS.

it. But we cannot as yet answer the more obvious and, one
might think, almost preliminary question as to what the
chief functions which are discharged by these two com-
ponents really may be. It is certain that the existence of a
nucleus is essential to morphological development such as is
implied in the production of new cells, and very probably
also in the further differentiation of those which have
already been formed. Instances of this are seen for example
in the growth or alteration of the cell wall. Haberlandt
(5) some years ago drew special attention to the fact
that when local thickening occurred in a cell wall the
nucleus commonly moved to this spot, and the present
writer has repeatedly observed it during the formation of
the hard coat found on many seeds ; here the deposition of
substance is usually localised on the inner parts of the cell,
and the nucleus takes up a corresponding position as soon
as the process begins. Korschelt (6) has observed a
similar relation to exist during the chitinisation of the mem-
branes of insect cells, and quite recently Istvanffi (Ber. Deut.
Gesel., Dec, 1895) has observed that when the tubular
hypha of Mucor branches, a nucleus is invariably present at
the spot whence the branch is arising. Strasqurger (3^) has
also drawn attention to the same truth, inasmuch as he
states that before the opening of the zoosporangium of
CEdogonium, the nucleus and kinoplasm aggregate in the
vicinity of the spot at which the hole is about to be formed.

But perhaps one of the most striking instances of the
directive effect of the nucleus as a whole is to be seen in
the result of an experiment of Boveri, who asserts that he
impregnated a non-nucleated piece of protoplasm of an
echinoderm ovum with the sperm nucleus of another species ; 1
development ensued, and the larva resembled the paternal
form (7).

In discussing the relations which exist, or are supposed
to exist, between the cytoplasm and the nucleus, it is clearly
of the first importance to know what are the changes which
occur in them, and especially in the nucleus, during the

1 The animals actually employed were Echinus microtuberculatus
(male), and Sphaerechinus granulans (female).

RECENT ADVANCES IN VEGETABLE CYTOLOGY. 31

growth, maturity and senescence of the cells. Some ex-
tremely interesting results in this direction have recently been
published by Zacharias (8). An ordinary resting nucleus
consists, as all biologists are aware, of a somewhat dense
thread-like framework, often spoken of as linin, which
usually exhibits copious anastomosis, sometimes to such a
degree that it almost forms a spongy texture. In this
framework granules are found embedded which react
definitely to stains and to solvents ; they constitute the
nuclein, a phosphorus-containing substance which at the
periods of nuclear division undergoes an enormous increase
in bulk. The linin is bathed in a more fluid substance, the
paralinin. One or more spherical bodies, the nucleoli,
are often present in addition to the foregoing constituents,
and the nucleus is delimitated from the cytoplasm by a
pellicle or membrane. The nucleolus contains, as was
shown by Zacharias many years ago, at least two
substances, one of which is of an albuminous nature, and is
dissolved out on treatment with gastric juice ; after peptic
digestion has extracted the albumin, a substance is left
which Zacharias calls Plastin. Now observation shows
that the relative proportion of these two constituents varies
considerably at different periods of the life of the cell, and
this is of importance in connection with the intricate series
of changes which the nucleus passes through during the
process of ordinary division. The conviction has slowly
been forced upon us within the last few years that there
exists a considerable variety amongst the bodies which
have been included in the common term of nucleoli.
Auerbach (9) showed in 1890 that some of them
absorbed certain red dyes with greater avidity than they did
certain blue ones, whilst other nucleoli reacted in the oppo-
site manner. He thus distinguished between erythrophil
and cyanophil nucleoli. These results have been extended
to plants by the investigations of Rosen (10) and others,
but especially by Zacharias, who has applied the test of
solvents to them, with the result that the difference between
the two classes of nucleoli proves to be a much more real
one than had hitherto been supposed. And these observa-

32 SCIENCE PROGRESS.

tions are specially interesting when considered from the
point of view of the great dissentience of opinion which exists
between most botanists and zoologists as to the nature and
function of the nucleolus. Strasburger, who admitted the cor-
rectness of Rosen's statements, considered that the difference
between an erythrophil and a cyanophil nucleus was largely
one of nutrition, and he instanced in support of his view
the difference between the erythrophil nucleolus in the
nucleus of the well-nourished oosphere and the cyanophil
nucleus of the much smaller, and therefore presumably
worse nourished generative cell of the pollen tube. But
Zacharias, in criticising Strasburger's views, considers that
there is no evidence to prove that the one nucleolus is in a
better position than another as regards its nutrition, and it
is still more difficult to accept the suggested explanation in
those cases in which both forms of nucleoli are concomi-
tantly present.

Zacharias has shown that whereas the erythrophil
nucleoli contain albumin and plastin, the cyanophil kind
(the "pseudo-nucleoli" of Rosen and others) contain nuclein,
a substance quite absent from the other class of nucleoli.
Rosen in 1892 stated his conviction that his pseudo-nucleoli
in reality consisted of chromatic substance (nuclein) and
that they contribute to the formation of those remarkable
bodies, the chromosomes, which are evolved by the break-
ing up of the linin framework after the amount of nuclein
has greatly increased in it, previous to the division of the
nucleus. Now the nucleolus exhibits striking chancres both
during the growth, and also during the division of the cell and
its nucleus. As regards the behaviour during cell growth, the
relation of the nucleolus to theothercomponents of the nucleus
is highly suggestive, and seems to support the view of those
who hold that its function is largely, at any rate, nutritive.

In the embryonic tissue situated at the growing points
of plants, the cells are all much alike, differentiation and
specialisation only taking place behind these regions.
Consequently it is possible to trace the changes which a
cell exhibits during its transition from a primitive state to
its adult form, and often, further, through the various stages

RECENT ADVANCES IN VEGETABLE CYTOLOGY. 33

of senescence and death. Some cells, indeed, are not really
useful to the plant of which they form a part, until they are
dead, i.e., till the wall of the cell alone remains, whilst from
its cavity the protoplasm has disappeared.

The researches of Zacharias and of Rosen, which have
recently been published, were directed especially to the
behaviour of nuclei in the apical regions of plants, and
their results in the main are confirmatory of each other,
though the two observers were interested in rather different
aspects of the same problem. The nuclei of all actively
dividing cells are markedly cyanophil, and this character is
especially noticeable just below the active generative cells.
At first sight it may seem remarkable that in a fern root
the nucleus of the large apical cell is less cyanophil than
are the nuclei of the dividing segment cells which have
been cut off from it. But the anomaly is only apparent,
for though all the cells in the root owe their origin ulti-
mately to the division of the apical cell, it must not be
forgotten that the nuclear divisions in the segments which
are cut off from it are far more frequent. The segments
divide up into a very large number of cells before they
finally form permanent tissue cells, and therefore it is not
surprising to find that the nucleus of the apical cell, which
is the ancestor of them all, contains less nuclein than the
more actively dividing descendants. But there are several
other significant observations which go to show that in cells
which are in a state capable of further division, this faculty is
correlated with the presence of nuclein in their nuclei. Rosen
found in the roots of the bean and other flowering plants
that after the tissues were beginning to show differentiation,
the zone of cells forming the pericycle1 retained, in their
nuclei, the characters of embryonic cells, that is to say,
that, whereas the nuclei of the rest were losing their cyano-
phil character and were becoming erythrophil, the pericyclic
•nuclei retained their nuclein contents. . Now the lateral
roots arise in this pericyclic layer, and they do so by the
differentiation in it of new growing points. Hence these

1 A zone of parenchymatous cells sheathing the more central wood and
bast parts of the vascular strand.

3

34 SCIENCE PROGRESS.

new rootlets can only be developed from cells which still
retain, or can re-awaken, embryonic characteristics. Be-
hind the region in which lateral roots arise, the cells of
the pericycle lose their cyanophil nature, and here again
the loss is first apparent in those cells from which, even
normally, no roots would originate, viz., those situated
opposite the phloem. It would be interesting to know
whether in the case of those roots in which the lateral
rootlets arise right and left of the protoxylem (e.g., Cruci-
ferse) a corresponding difference obtains.

Again, Zacharias noticed that during the development
of the guard-cells of the stomata in a number of leaves
a similar difference held good. In a simple case, e.g.,
many Liliacese, the mother-cell of the guard-cells is cut
off from a cell which is destined at once to form one of the
ordinary and relatively large epidermal cells. In this case,
whilst the nucleus of the mother-cell of the stoma retains
its nuclein contents, the other one rapidly becomes poorer
in this constituent, it grows and develops a large nucleolus.
The small mother-cell again divides to form the guard-cells
of the stoma, and only then does a nucleolus become at all
conspicuous, and the nuclein diminish in quantity. And
therewith the further capacity for division ceases.

Besides the connection which is shown to exist between
a nucleus which is capable of division, and its richness in
nuclein, there are certain other facts of importance which
demand notice. The nuclei of cells which are actively
dividing are commonly characterised by the possession of
smaller nucleoli than are those in which no further divisions
will take place, but which are still growing in size. In fact
Zacharias states generally that, as regards nuclei of cells
emerging from the meristem region, the nucleoli first
increase to a maximum, that this is accompanied by an
enlargement of the nucleus as a whole, which however only
reaches its maximum size after the nucleolus has done so,
and that the latter body then diminishes faster than does
the nucleus as a whole.

Further, Zacharias found that not only is the nucleolus
losing substance in those cells which are specialising to

RECENT ADVANCES IN VEGETABLE CYTOLOGY. 35

form tracheids, vessels and sieve tubes, but that the nucleus
as a whole is losing, and still more rapidly, those substances
which are capable of being removed by peptic digestion
from the cell. The facts seem to suggest that it is albumin,
or some other proteid, which is disappearing ; and it is
clear that the loss is due to a change in the nucleus itself,
irrespective of the amount of nutrition available in the
surrounding plasma, since the change is extremely obvious
in the degenerating nuclei of sieve tubes, in spite of
the fact that they are surrounded by abundant albuminous
substances in the slimy contents of the cells. On the other
hand, in those cells which are growing in size, preparatory
to further divisions, such as in spore-mother-cells, the
increase in albuminous substances, both in the nucleus
generally, and especially in the nucleolus, is strongly marked.
Spore-mother-cells, as a rule, pass through a relatively long
period of growth, and hence we might perhaps anticipate
(as we find to be the case) that they exaggerate the changes
seen in the dividing and growing cells of the apical meri-
stem. But I do not wish to lay too much stress on this,
because we know that other, and profound, changes occur
during the growth of spore-mother-cells, and it is uncertain
to what extent the facts just mentioned may be connected
with them.

It may possibly be objected that observations like those
of Zacharias are open to adverse criticism on the ground that
the chemistry, and a fortiori the microchemistry, of the
proteids and other substances which occur in cells is as yet
in such an unsatisfactory condition. But this objection is
really not a legitimate one. We know that certain struc-
tures in the cell are differentiated by their selective action
on certain dyes, and it is to this fact that their recognition
was due in the first instance. But we find the action of
certain solvents to yield no less definite results. Given a
nucleus in a particular condition (as judged by the structure
rendered visible by staining), and it will be found that the
degree of solubility of its constituent substances is charac-
teristic for the particular stage in the life history of the cell
or of the nucleus which may happen to have been selected.

36 SCIENCE PROGRESS.

Hence it seems clear that the two methods ought both to
be employed ; for whilst the staining exhibits more or less
completely the structural arrangement of the substances
present, the microchemical method not only indicates some
at least of the important differences which exist between
the different structures revealed by the action of staining,
but it teaches us that certain of these same structures are by
no means so homogeneous in their nature as one might be
led to suppose relying on the evidence derived from stain-
ing alone.

But those who pin their faith on stains sometimes seem
to forget that they are after all only employing a sort of
microchemical method themselves. For the fact that
different histological elements of the cell are distinguishable
by stais, implies the existence of a chemical dissimilarity
between them. And this becomes the more obvious when,
owing to periodically recurring changes in the cell, we
assert that this or that structure is growing or diminishing.
The investigator who is consciously proceeding on micro-
chemical lines is at least not so open to the charge of mere
empiricism as are those who look for salvation to
haematoxylin or the anilin dyes. He may be wrong in
supposing, for example, that the phosphorus within the
nucleus only occurs in the nuclein, just as he may be in
error in assuming that the substance nuclein itself really re-
presents a chemical substance in the same way that sugar
does. But he materially advances our knowledge of the
cell when he determines the fact that a body which fluctuates
in size as does the nucleolus, is composed of two substances
or groups of substances one of which is soluble in gastric
juice whilst the other is not ; and that further, the relative
size is, in the first instance, correlated with the amount of
substance which the fermentative action of pepsin can render
soluble.

It is readily conceded that the bodies we call nuclein,
plastin, and the like, possibly may not, as stated already,
represent chemical molecules at all. This does not, how-
ever, diminish the interest attaching to the proof that this
or that substance is at one time present, while at another

RECENT ADVANCES IN VEGETABLE CYTOLOGY. ^

time it can be no longer recognised in its former place.
Nor does this observation lose in importance when the
differences are shown to closely accompany changes in the
general characters of the cells themselves.

BIBLIOGRAPHY.

(i) WAGER, H. Preliminary Note on the Structure of Bacterial
Cells. Annals of Botany, vol. ix.

(2) Von Sachs. Physiol. Notizen II. Flora, 1892. Also

Physiol. Notizen IX. Flora, Erganzungs bd., 1895.

(3) STRASBURGER. Ueber d. Wirkungssphare d. Kerne u. d.

Zellgrosse. Histologische Beitrdge, v., 1893.
(3«) STRASBURGER. Schwarmsporenjgameten.Pflanzlichen sperm-
atozoiden, und das Wesen d. Befruchtung. Hist. Beitr., iv.,
1892.

(4) Boulenger, G. A. On the Scaling on the Reproduced Tail

in Lizards. Proc. Zool. Soc, 1888.

(5) HABERLANDT, G. Ueb. d. Beziehungen Zwischen Function

u. Lage d. Zellkerns b. d. Pflanzen. Jena, 1887.

(6) KORSCHELT. Beitrager 2. Morph. u. Physiol, d. Zellkerns.

Zool. Jahrb., 1889.

(7) BOVERI. Ein Geschlechtlich erzeugter Organismus ohne Mtit-

terliche Eigenschaften. Sitzungsber. d. Gesellsch. f. Morph.
u. Physiol, zu Miinchen, 1889.

(8) ZACHARIAS, E. Ueb. d. Verhalten d. Zellkerns in Wachsenden

Zellen. Flora, Erganzungs bd., 1895.

(9) AUERBACH, L. Zu Kentniss d. Thier. Zellen. Sitzungsber. d.

Kgl. Preuss. Akad. d. Wissensch., 26th June, 1890.
(10) ROSEN, F. Ueb. tinctionelle unterschied verschied. Kernbes-

tandtheile u. d. sexualkerne. Colitis Beitr. z. Biol. d. Pflanzen,

v., 1892.
(iOtf) ROSEN, F. Beitr. z. Kentniss d. Pflanzenzellen. Colitis

Beitr., vii., 1895.

J. Bretland Farmer.

THE MORPHOLOGY OF THE MOLLUSCA.

^> H E recent publication of a number of new manuals and
monographs dealing with the Mollusca offers a favour-
able opportunity for a review of our knowledge of this
great phylum of the animal kingdom. It is not fifteen
years since Professor Lankester's classical article on Mollusca
was published in the Encyclopedia Britannica, yet the con-
tributions to Molluscan morphology since that date have
been not only numerous, but in many cases of prime im-
portance.

The older method of inquiry, that of the comparison of
types more or less arbitrarily selected from different groups,
has been succeeded by investigations more directly in-
fluenced by the idea of evolution. The comparison of types
has been replaced by the study of groups. The founda-
tions of the morphological edifice were laid upon the former
method ; the superstructure and details are the result of
the latter. Homologies having been to a large extent
determined, we now seek phylogenies. It happens also
from time to time that the detailed study of a group with
the object of reconstructing the phylogeny of its members
leads occasionally to the discovery that homologies based
on the simple method of anatomical comparison turn out
to be nothing more than analogies — recurrent examples of
similar modifications.

One result of these phylogenetic inquiries has been the
concentration of particular attention upon forms which are
presumably the most primitive in each group ; and great
advances have thus been made in our knowledge. Kow-
alewsky and Marion, Pruvot, Wiren, and Thiele have
enormously extended our acquaintance with the Apla-
cophorous Isopleura ; primitive Prosobranchs (Docoglossa
and Rhipidoglossa) have been thoroughly investigated by
Haller and Boutan ; Bouvier has thrown new light upon the
Opisthobranchia by his researches on Actceon ; Boas and
Pelseneer have revolutionised our ideas of the Pteropoda

THE MORPHOLOGY OF THE MOLLUSC A, 39

by their work upon Limacina among the Thecosomata, and
upon Dexiobranchcea and other types among the Gymnoso-
mata ; the morphology of the Pelecypoda has been further
elucidated by Pelseneer's observations upon Nucula and
other primitive forms, and important contributions to our
knowledge of the Cephalopoda were made during the past
year by Huxley and Pelseneer in the case of Spirilla, that
last survivor of the ancient types of Decapod Dibranchiates.
We doubt if any equivalent group of the animal kingdom,
except perhaps the Echinoderma, has been the subject of
such productive researches as the M ollusca during the period
under consideration ; and certainly the phylogenetic method
of inquiry has attained no greater triumphs than in the
hands of Bouvier, Haller, Pelseneer, and other inves-
tigators of the Gastropod and Lamellibranch series.

In the present article I propose to deal more especially
with recent contributions to our knowledge of the Molluscan
nervous system, reserving a fuller consideration of other
questions for a later article.

There is one writer, however, whose views must first of
all be dealt with, as on a great number of fundamental
points they are opposed to all current conceptions of
Molluscan morphology. These views merit some detailed
consideration, moreover, for they are based on propositions
which are not without a certain appearance of plausibility,
and may well serve as test-questions by which to examine
into the accuracv of the homologies which have been
generally admitted to exist between the different sections
of the Molluscan phylum.

Thiele has published his views in a series of lengthy
papers, the references to which will be found in the biblio-
graphy (23, 24, 25). He regards the Mollusca and Anne-
lida as direct descendants of Polyclad Turbellarians, and
his identifications of homologous organs in the different
Molluscan groups are determined, not by a direct comparison
of the organisation of these types one with another, but
by independent comparisons of the organisation of the
different Molluscan types with that of sucker-bearing
Polyclads. The group Mollusca is thus made to lose its

40 SCIENCE PROGRESS.

compactness, and characteristic organs, such as mantle and
ctenidium, which have been regarded as homologous
throughout the Molluscan series, are interpreted in different
ways in the different types, as the exigencies of Thiele's
theory demand. One of the first propositions assumed by
this writer is that the foot of the Mollusca is simply a colossal
enlargementof the ventral sucker of the Polyclad; thesuctorial
function of the foot in Chiton and the lower Gastropoda is
pointed to in support of this comparison. A series of
more revolutionary propositions is then promulgated in
consequence of the necessity under which the author is
placed of discovering the primitive body-edge of the
Mollusca comparable to the edge of the body of the Tur-
bellaria. This primitive body-edge Thiele identifies by
means of the lateral sense-organs which characterise the
epipodium in the Rhipidoglossa and the margin of the
mantle in Pelecypoda. The epipodium in Gastropoda and
the mantle edge in Pelecypoda are thus taken by this writer
to represent the sides or edge of the body in the Tur-
bellarian ancestor. The epipodium in Gastropoda and the
mantle edge in Pelecypoda consequently separate the
dorsal from the ventral regions of the body in those groups.
It follows from this that the ctenidia of Gastropoda, which
are supra-epipodial in position, are not homologous with
the ctenidia of Pelecypoda, which are infra-pallial. How we
are to regard the anus, which is dorsal in the one group and
ventral in the other, is not explained. But since in oper-
culate Rhipidoglossa the operculum, like the shell, is
situated above the epipodium, we are told that the oper-
culum must also be regarded as dorsal in position, as well
as serially homologous with the shell proper. This, in
Thiele's eyes, compares well with the condition of affairs in
Chiton, whose shelly plates are without doubt serially
homologous. Moreover, although the existence of an
epipodium in Chiton has not been hitherto recognised,
Thiele argues that, since the pallial fold in this form re-
presents the primitive body-edge, it must also, together with
the series of ctenidia which are attached to its lower surface,
be regarded as the homologue of the epipodium of the

THE MORPHOLOGY OF THE MOLLUSC A. 41

Rhipidoglossa. The ctenidia of Chiton are, in fact, re-
garded as modified epipodial cirri. The consequence of
this view is that while the mantle of Chiton and the mantle
of Pelecypoda are regarded as homologous, the mantle of
the Gastropoda is supposed to represent only a portion of
the mantle in these other forms, and its projecting rim,
similar as it appears to be in the two cases, is held to be a
new and secondary formation unrepresented in the Am-
phineura and Pelecypoda.

Nowhere, however, do we find in Thiele's voluminous
writings any explanation of the anomaly which ought to
have occurred to him, that while in Chiton the anus is
"ventral," and lies well beneath the "epipodium" and the
last shell-plate, in operculate Gastropods the intestine opens
not only above the epipodium, but between the operculum
and the shell of the embryo — a relation which could only be
represented in Chiton, if Thiele's theories were correct, by
the situation of the anus between two of the shell-plates
upon the back of that animal !

The nervous system of the Mollusca is treated by Thiele
with a ruthlessness no less than that which is meted out
to the external organs of the body. Let us take the
Amphineura first. In this group, if the relations of the
nervous system in Chiton be taken as typical, we have
dorsal to the gut a great ganglionic nerve-ring whose lateral
components are usually referred to as the lateral or pleuro-
visceral cords. Connected anteriorly with the cerebral
enlargements of this nerve-ring is a pair of ventral or pedal
cords, connected with one another by a series of commis-
sures lying beneath the gut, and also with the lateral cords
by means of lateral connectives. The lateral cords inner-
vate the pallial sense-organs, gills, and viscera ; the ventral
cords the musculature of the foot. The lateral cords are
regarded by Thiele as the homologues of the lateral cords
or nerve-ring of the Turbellarians. and the ventral cords are
taken to correspond to the ventral longitudinal nerves of
the same forms. So far we find nothing either erratic or
original, for the same view has already been taken by Lang

(16).

42 SCIENCE PROGRESS.

But the novelties begin with Thiele's interpretations of
the nervous system of Gastropoda and Pelecypoda. We
have already pointed out Thiele's view that the epipodium
of Gastropods represents the primitive body-edge. Now
at the base of the epipodium in Fissurella and Haliotis there
lies a ganglionic plexus ; and this plexus, which takes the
form of an incomplete ring, is regarded as the homologue
of the lateral cords of Turbellarians and Amphineura. The
series of epipodial nerves which connect the epipodial plexus
with the upper half of the pedal cords in Rhipidoglossa is
compared with the series of connectives between the lateral
and ventral cords in Amphineura.

This seems very plausible until one recollects (i) that,
the epipodium being infra-rectal, the epipodial plexus is
also infra-rectal and thus difficult to compare with the
lateral cords of Amphineura, whose "commissure" is supra-
rectal ; and (2) that, whereas in Amphineura the lateral
cords innervate practically the whole of the pallium and
viscera, in Rhipidoglossa the epipodial plexus has nothing
to do with any other organs except the sense-organs of the
epipodium. If the pallium of the Gastropoda is really, as
Thiele maintains, a secondary differentiation of the primary
pallium of the Amphineura, one would expect that its
innervation would also be effected by progressive differen-
tiation of the nerve-centres which supplied the primary
pallium, viz., from the lateral or epipodial centres. So far
from this being the case, however, Thiele himself (xxv., pp.
587-9) adopts the view that the pallial nerves as well as the
pleural ganglia of Gastropoda are secondary derivatives of
the ventral or pedal cords.

The recklessness of Thiele's comparisons reaches its
high-water mark, perhaps, in his remarks on the nervous
system of Pelecypoda. Correlated with the existence of
numerous sense-organs (eyes, tentacles, etc.) along the
mantle edge, there exists in many forms {Area, Pecten,
Pinna, etc.) a nervous ring around the mantle which may
take the form either of a complete ring of peripheral ganglia
united by a plexus, or of a circumpallial ganglionated nerve,
as was recognised by Duvernoy (5) more than thirty years

THE MORPHOLOGY OF THE MOLLUSC A. 43

ago. Since the mantle-lappets of the two sides of the body
unite posteriorly above the anus, this pallial nerve-ring lies
above the gut. The ring is connected with the cerebro-
pleural ganglia by means of the anterior pallial nerves, and
with the visceral (parieto-splanchnic) by means of branches
from the great posterior pallial nerves. Accordingly Thiele
homologises the circumpallial nerve-ring with the lateral
cords of Chiton and with the epipodial plexus of the Rhi-
pidoglossa.

The first of these homologies seems not unreasonable, for
no one disputes the homology between the mantle of Chiton
and that of Pelecypoda. Moreover Kowalevsky's discovery
that Chiton in its later embryonic phases is provided with
a pair of transitory eyes which lie outside the velar area
and have some close connection with the lateral nerve-
cords, renders this comparison particularly worthy of
attention. But how the circumpallial nerve of Pelecypoda
can be in any sense homologous with the epipodial plexus
of Gastropoda, when the latter structure lies beneath the
gut and has no connection with the cerebral ganglia, either
directly or by the intermediation of the pleural ganglia, it
is altogether impossible to conceive. And this is not all.
The posterior connection between the circumpallial nerve
of Pelecypoda and the visceral ganglia is compared by
Thiele with the posterior connectives between the lateral
and ventral cords of Amphineura ; and the time-honoured
visceral nerve-cords of Pelecypoda, with the visceral (parieto-
splanchnic) ganglia upon them, are homologised with the
ventral cords of the Amphineura. To reveal the absurdity
of these comparisons it is sufficient, I think, to remind my
readers that the ventral cords of Chiton are concerned ex-
clusively with the innervation of the musculature of the
foot ; while the visceral cords of Pelecypoda innervate
the body-wall, ctenidia and viscera^ in addition to the
posterior adductor muscle. How these supposed homo-
logues of the ventral cords of Chiton have come to assume
so many of the functions of the lateral or pallio-visceral
cords, is not explained ; and since Pelecypoda possess a
pair of pedal ganglia in the foot, as typical in their relations

44 SCIENCE PROGRESS.

as those of any Gastropod — in Nucula to the extent even
of having separate cerebro-pedal and pleuro-pedal connec-
tives (18, 19) — it seems profitless to pursue these ill-
balanced speculations any further.

The utmost ingenuity cannot overcome the fact that
there is a fundamental disparity between the Turbellarian
and Molluscan body. This disparity is revealed by em-
bryology ; but to embryology Thiele pays scant attention.
Thiele's argument is practically this (24, p. 504), — that
the only route from Ccelenterates to Bilateralia is via the
Ctenophores to Polyclads, and that Annelids and Molluscs
are consequently to be derived from Polyclad ancestors.
Embryology seems to me, however, to point to two lines of
descent at least, from the Ccelenterates to the Bilateralia.
In each case the oral surface of the Ccelenterate ancestor
became the ventral surface of the Bilateral descendant ; but
along one line of descent the primitive mouth or blastopore
retained its ancestral form as a simple circular orifice in the
middle of the ventral surface, and opened into a gastral
cavity devoid of an anal orifice (Polyclads) ; while along the
line of descent which led to the Annelida and Mollusca the
blastopore elongated along the ventral surface, as Sedg-
wick has so ably contended, its lips coalesced except at the
two extremities, and these open ends constituted the mouth
and anus of the Ccelomate descendants. Thiele has
altogether overlooked the significant behaviour of the blas-
topore in Annelidan and Molluscan embryos ; and since
no similar modification of the blastopore is known in the
case of Turbellarians and Trematodes, in which groups the
absence of an anus is so marked a characteristic, we are
amply warranted, I think, in drawing the conclusions which
I have emphasised above.

The admission of this distinction is however fatal to
any theory of the Polyclad ancestry of the Mollusca. The
foot of the Mollusca is a development of the fused lips of
the elongated blastopore, and can in no case be homo-
logised with the ventral sucker of Turbellarians which lies
entirely behind the blastopore. The same remark applies
to Lang's comparison of the Molluscan foot with the ventral

THE MORPHOLOGY OF THE MOLLUSC A. 45

surface of the Turbellarian. The foot is undoubtedly part
of the ventral surface of the Mollusc, and as such may be
compared, in a general way, with the creeping surface of a
Planarian ; but as a specialised organ, developed from the
fused lateral margins of a slit-like blastopore, it has no
homoloeue in the organisation of the Turbellaria.

Let us now see what light has been thrown on the
problems of Molluscan morphology by the researches of
other investigators.

The visceral commissure. — One of the greatest dif-
ficulties in comparing the Amphineura with the Gastropoda
or other Molluscan types has long been the fact that the
lateral or pleuro-visceral cords of Chiton, which innervate
the gills, viscera, and mantle, are united to one another
posteriorly by a "commissure" lying above the rectum;
whereas the visceral commissure of Gastropoda and Pelecy-
poda, etc., lies below the intestine.

A little care in the use of words would have prevented
much of the confusion and controversy which has arisen on
this subject of the position of the visceral commissure.
Words, as Bacon phrases it, put constraint upon the in-
tellect, and there is no doubt that the disagreement and
perplexity of naturalists concerning this point have been
caused by one of the idola fori which they have themselves
set up, rather than by any intrinsic incompatibility in the
facts themselves. If the language must still be maintained,
I must at least point out that there are commissures and
commissures, and that one may be a commissure in fact,
and another only in name. The suprarectal ''commissure"
in Amphineura is ganglionic, and, like the rest of the
pleuro-visceral nerve-ring, is formed in situ by delamination
from the ectoderm (15). It is not a commissure in the
strict sense of the word, but an integral portion of an
annular central nervous system. But the visceral loop of
other Molluscs consists merely of nerve-fibres connecting
usually a couple of visceral ganglia with one another, and
with the pleural ganglia. Now nerve-fibres are outgrowths
from nerve-cells, and if two groups of nerve-cells should
happen to take a somewhat deep-seated position in the body

46 SCIENCE PROGRESS.

before their fibres have grown out (which is not a rare
embryological phenomenon), there should be nothing in-
comprehensible in their fibres taking the shortest route and
meeting beneath the gut instead of over it. Clearly, there-
fore, the ventral position of the visceral commissure in
most Mollusca by no means precludes the possibility of the
essential homology between the visceral loop of these
forms and part of the pleuro-visceral ring of Amphineura.

The other differences between the visceral loop of most
Mollusca and the pleuro-visceral ring of Amphineura are-
principally differences in the degree of segregation and
concentration of ganglion-cells and nerve-fibres. The
pleuro-visceral ring of Chiton represents a very primitive
nervous system, characterised by the more or less even
diffusion of ganglion-cells over the whole length of the
cord, while the nerves arising from it are not united into
large trunks, but are given off at repeated intervals in a
manner which is almost metameric. The nerves springing
from it innervate the same parts of the body as the com-
bined pleural and visceral ganglia of Gastropods and other
Molluscs, viz., mantle, ctenidia, intestine, heart, nephridia,
and gonads. But if, after the reduction of the ctenidia to
a single pair, we imagine a process of segregation to set in
between these various elements, the more strictly visceral
centres would become separated from the superficial pallial
centres, and would assume a deeper position in the body.
The law of concentration would apply in this as in other
cases of evolution of nervous systems (3), and the result of
the whole process would be the differentiation of a visceral
nervous system, consisting of ganglia and commissural
fibres, out of the primitively mixed and diffuse pleuro-visceral
system. If the primitive relations to the gut and ring-like
form were retained at all, they would be retained, not
necessarily by the visceral system, which has ex hypothesi un-
dergone considerable changes, but by the pallial (= pleural)
system, which has undergone no change, except possibly
one of incipient concentration.

The position of the commissural fibres of the visceral
ganglion in relation to the gut becomes a matter of sub-

THE MORPHOLOGY OF THE MOLLUSC A. 47

ordinate importance if the evolution of the nervous system
has proceeded upon these lines, as will be made evident
later on. As a matter of fact the visceral commissure is
situated below the gut — a relation which is possibly fore-
shadowed in Chiton by a connection beneath the gut of the
two gastric nerves described by Haller (8).

Pelseneer (19) indeed goes so far as to identify these
gastric nerves of Chiton with the visceral commissure of
Gastropoda and Pelecypoda; but the considerations which I
have emphasised above show that the typical visceral nerves
and commissure have not yet arisen in the Amphineura ;
they do not arise, in fact, until the branchial, nephridial,
genital and enteric branches of the primitive pallio-visceral
cords are all united into one common trunk. There is
some doubt, moreover, as to the existence of the gastric
nerves described by Haller, since two investigators, Plate
(20) and Thiele, have been unable to discover them in
species of Chiton examined by themselves.

A valuable contribution to this part of the subject is
contained in Haller's recent Studien (11). In the
common cyclobranchiate types of Limpet the pallial nerves
are separate from one another behind, and seem to be
mere outgrowths of the pleural ganglia (Bouvier, 3, p. 19);
but in Lottia, one of the more primitive monobranchiate
forms, Haller shows that the pallial nerves of the two sides
are directly continuous with one another posteriorly, and make
a complete arch round the edge of the mantle. They are
moreover not mere nerves, since they consist of a core of
fibres surrounded by an outer coating — discontinuous, it is
true — of ganglion-cells. They are clearly the posterior
continuations of the pleural ganglia, and represent the re-
mainder of the pallio-visceral nerve-ring of the Amphineura
after the separation of the visceral elements. This view is
further borne out by the existence of several connectives
between the pallial ring and the pedal cords in addition to
the stout ganglionic connective which in higher forms
becomes the persistent pleuro-pedal connective.

The pleural ganglion. — Haller's discovery recorded in
the preceding paragraph shows clearly the error of the

48 SCIENCE PROGRESS.

view by which the pleural ganglion is regarded as a
derivative of the pedal cords (Bouvier, Pelseneer, etc.,
passim). This view is founded on the fact that in the lower
Gastropoda (Docoglossa and Rhipidoglossa) the pleural
ganglia are directly continuous with the anterior ends of
the pedal cords, while in the higher types the pleural ganglia
gradually move further and further away from the pedal
ganglia, and, travelling along the cerebro-pleural connectives,
eventually come into contiguity with the cerebral ganglia
(Tenioglossa) or even fuse with them to form a single
cerebro-pleural ganglion on each side (Pelecypoda).

The close connection between the pleural and pedal
ganglia in the lower forms may now be interpreted
in a different manner. The ganglion-cells which were
primitively distributed over the whole extent of the pallial
nerve-ring have been concentrated at the anterior ex-
tremities of its lateral portions, as Haller's observations
on Lottia show— or rather in the reo-ion of the first
pleuro-pedal connective, for the most anterior portion of
the primitive pallial cords is represented by the cerebro-
pleural connective. The shortness of the pleuro-
pedal connecting piece and the great concentration of
ganglion-cells which takes place at its two extremities
prevent any sharp demarcation between the pleural and
pedal ganglia in these lower forms ; but a comparison of
the nervous system of Lottia with that of Chiton (Thiele,
2 3 ? P- 387) leaves no room for doubt as to the correct-
ness of this interpretation, which throws a flood of light
upon numerous other points which have been difficult to
understand upon the older views. It explains, for example,
why the cerebro-pleural and cerebro-pedal connectives
should be already distinct from each other in the lower
Gastropods at a stage when the pleural ganglia are in
actual continuity with the pedal cords, and it sets at rest
the controversy as to the meaning of the lateral furrow
in the pedal cords of Rhipidoglossa which has been waged
with so much skill in the rival pages of the Archives de
Zoologie and the Bulletin Scientifique de la France et de la
Belgique.

THE MORPHOLOGY OF THE MOLLUSC A. 49

Development of the pleural ganglion. — That the pleural
ganglion is essentially distinct from the pedal is, I think,
sufficiently clear from the facts of development. Although
these ganglia are placed so close together and are so inti-
mately connected in the lower Gastropods there is not a
single case on record in which the pleural ganglion has been
observed to arise from the pedal ganglion, or from a
common pleuro-pedal rudiment in the embryo. It is
equally true on the other hand that Sarasin's derivation of
the cerebral and pleural ganglia from a common rudiment
in Bithynia (the cephalic sense-plate) has been opposed by
v. Erlanger, who shows that all the great ganglionic centres
arise separately, and do not become connected with one
another until after their differentiation (7).

A renewed investigation of the origin of the cerebro-
pleural ganglion in Pelecypoda would be of great interest
in this connection. Pelseneer's ( 1 8) observations on Nuctila
have placed the fact of the composite nature of this ganglion
in Pelecypoda beyond all doubt ; and still, to the best of
my knowledge, no one has yet observed the appearance in
the embryo of a pleural element distinct from the main body
of the ganglion. This apparent community of origin of the
cerebral and pleural ganglia in Pelecypoda may be compared
with the direct continuity of the cerebral and pleural
elements of the nervous system in Amphineura.

Development of the visceral ganglia. — Sarasin en-
deavoured to show that the visceral ganglia of Bithynia,
together with the pedal and abdominal ganglia, arise in the
embryo from a common ventral proliferation of the ectoderm
which he compares with the ventral ganglionic chain of
Annelida. On this point also Sarasin has been corrected
by v. Erlanger, who shows that all these ganglia arise
separately from one another in Bithynia (7), as well as in
Palndina (6).

The visceral ganglia are also quite distinct from the
pleural ganglia in their origin, as v. E Hanger's observations
show. In one important respect, however, the visceral
ganglia and the pleural ganglia betray a marked similarity,
the significance of which seems, however, to have escaped

4

50 SCIENCE PROGRESS.

the attention of its discoverer. In Paludina v. E danger
figures the pleural ganglia arising from the ectoderm on
each side of the body at a point just outside the velar area,
but in actual contiguity with the cells of the ciliated ring.
In Bithynia (7, Taf. xxvi., fig. 16) he figures the same
condition of things for the pair of visceral ganglia. The
only difference in origin between the two ganglia is that the
visceral ganglia arise behind the pleural ganglia. If the
Molluscan veliger possessed a nerve-ring beneath its proto-
troch (velum), as occurs in the trochosphere of the Annelida,
it is quite clear that the pleural and visceral ganglia of
Bithynia and Paludina would represent a series of gangli-
onic thickenings along the course of the nerve-ring. Apart
from this inference, however; the topographical relations to
which I have called attention seem sufficient to establish
the proposition that the pleural and visceral ganglia, and,
as I shall show directly, the abdominal ganglion also, of
Gastropods — and, therefore, of other Mollusca — belong to
a group of dorso-lateral nerve-centres quite distinct from
that which is represented by the ventral or pedal cords.
Here again we are reminded of the direct continuity of the
pleural and visceral nerve-centres in the Amphineura.

Development of the abdominal ganglion. — In Chiton,
as Kowalevsky has shown (15), the unpaired abdominal
ganglion, or, as it is often called, the visceral ganglion,
arises by a proliferation of the ectoderm at the hinder pole
of the embryo, dorsally to the site of the future proctodeum.
In the adult this ganglion is simply a special concentration
of ganglion-cells on the supra-anal portion of the pleuro-
visceral ring.

The abdominal ganglion of Gastropods is also situated
at the hinder end of the visceral loop, but lies of course
ventral to the gut. Can these two ganglia be regarded as
homologous ?

If Molluscs were mere mechanical models the answer
would be undoubtedly in the negative ; but embryology
points unhesitatingly to the opposite conclusion. Von
Erlanger has shown that in Bithynia as well as in Paludina
the abdominal ganglion develops as an ectodermal pro-

THE MORPHOLOGY OF THE MOLLUSC A. 51

liferation of the floor of the mantle-cavity, i.e., that the
ganglion is essentially a dorsal ganglion. Its final situation
on the course of the sub-intestinal nerve-loop is rendered
possible by the fact that its connectives with the visceral
eanolia are not delaminated from the ectoderm, as are the
ganglionic pleuro-visceral cords of Chiton, but are mere
fibrous outgrowths from the ganglia themselves. Embry-
ology is thus in complete accord with the views which have
been maintained in the earlier part of this paper as to the
homologies and origin of the visceral nervous system in
Mollusca.

The pallial and visceral commissures in Cephalopoda.
— It has long been known (Hancock) that in many Cepha-
lopoda the stellate ganglia on the pallial nerve-cords are
connected with one another above the gut by a transverse
commissure. Is this commissure a relic of the pallio- visceral
nerve-ring of the Amphineura and homologous with the
pallial ring of Lottia, or is it merely a secondary connection ?

In Spirilla a remarkable arrangement of the pallial
commissure has been recognised by Huxley and Pelseneer
in their recent memoir (12). The commissure is not in
this case a straight transverse band, but consists of two
curved cords which arise from the right and left stellate
ganglia respectively, and at their junction in the median
line of the body give off a median pallial nerve which runs
for a short distance forwards, and then passing over the
anterior margin of the shell — which is, of course, internal —
becomes recurrent and runs along the part of the mantle
contained within the last chamber of the shell. Pelseneer is
thus led to regard the commissure with its median nerve as
formed by the two original pallial nerves fused together.
The connection between the stellate ganglia having thus
arisen in the primitive Dibranchiates (apparently in con-
nection with the reduction in size and enclosure of the
chambered shell), higher forms show a series of stages in
its subsequent degradation, until it is finally lost in the
Octopoda. The absence of a pallial commissure in Nautilus
also supports Pelseneer's view that in Cephalopoda this
structure is not of any primary importance.

52 SCIENCE PROGRESS.

At the same time when Pelseneer added a paragraph to
the effect that the supra-rectal commissure of the Amphi-
neura is also a merely secondary junction of the pallial
nerves, he was probably not yet acquainted with Haller's
work on Lottia, and allowed his views upon the Polychsete
ancestry of the Mollusca to bias his interpretation of the
Molluscan nervous system.

In a recent paper on the anatomy of Nautilus Mr.
Graham Kerr (13) also refers to the question of the supra-
rectal commissure. It will be remembered that in Nautilus
the pleuro-visceral ganglia of the two sides form a stout
ganglionic band encircling the oesophagus in the region of
the cerebral ganglia. The pallial nerves radiate from the
lateral portions of this half-ring, and the pair of visceral
nerves arise from the ventral portion. The visceral cords
pass backwards on either side of the vena cava, and, after
giving off the branchial nerves, are prolonged posteriorly as
far as the post-anal papilla, behind which Mr. Kerr has
recognised an apparent anastomosis. Mr. Kerr adds that
in this case " the homologue of the pleuro-visceral cord of
Chiton is not merely the posterior sub-cesophageal nerve-
mass, but rather the two lateral portions of this, together
with the post-branchial prolongations which run on either
side of the vena cava. The mesial part of the posterior
sub-cesophageal nerve-mass would therefore be a secondary
fusion between the nerve-masses of the two opposite
sides."

In his suggested homology of this possible post-anal
{i.e., supra- rectal) commissure of the visceral nerves in
Nautilus with the supra-rectal " commissure " of Chiton,
Mr. Kerr has undoubtedly failed to appreciate the true
nature of the posterior sub-cesophageal loop of Nautilus, as
well as the relation of the visceral nerves to the pleuro-
visceral cords of Chiton. The explanation of the Cephalo-
pod nervous system is most readily found by comparing it
with that of Dentalium, whose organisation in many respects
supplies connecting links between that of the Cephalopoda
and that of the primitive prae-torsional Gastropod or
primitive Pelecypod. In Dentalium (22, p. 401) we find

THE MORPHOLOGY OF THE MOLLUSC A. 53

a pair of post-anal prolongations of the visceral nerves
precisely resembling those described by Kerr in Nautilus ;
yet in Dentalium, owing to the smaller degree of concen-
tration or cephalisation which has taken place in the
nervous system, it is easy to see that the typical sub-intes-
tinal visceral commissure exists as in Gastropods and
Pelecypods. The posterior sub-cesophageal nerve-mass
of Cephalopods has clearly been produced, not, as Mr.
Kerr suggests, by a secondary fusion of the pleuro- visceral
nerve-masses of the two opposite sides, but by a simple
shortening of the visceral loop as it occurs in Dentalium.
This would bring the visceral ganglia into continuity
with the pleural ganglia and with one another, — a process
of condensation with which we are already familiar in the
Tenioglossa and the Euthyneura among Gastropoda.

It may here be mentioned that Willey's simultaneous
account (26) of the visceral nerves of Nautilus, while con-
firming Mr. Kerr's observations as to the existence of post-
anal prolongations of a pair of visceral nerves, differs from
his statement as to their origin. Willey states that the
nerves supplying the post-anal papilla arise independently
from the sub-cesophageal visceral loop, although at their
origin they are adjacent to the branchial nerves and for a
large part of their course are actually contiguous with them.
The significance of this separation is not remarked upon by
Willey ; but if the separation really exists it is certainly a
difficulty in the way of his contention that the post-
anal papilla represents an approximated posterior pair of
branchial sense-organs, since the anterior osphradium and
both gill-plumes are all innervated from the outer visceral
nerve.

Etithyneurism. — Since the publication of Spengel's paper
on the olfactory organ and nervous system of Mollusca, a
division of the Gastropoda into two groups, the Strep-
toneura and the Euthyneura, has been generally adopted.
This classification has been accepted, moreover, not merely
as an expression of the anatomical facts concerning the
condition of the visceral loop in the two groups, but as a
classification of phylogenetic significance. It is to be in-

54 SCIENCE PROGRESS.

ferred that the two groups have been independently derived
from a common type of archi-Gastropod, possessing an un-
twisted visceral loop — the Prosobranchs (Streptoneura) by
the twisting of the loop, the Opisthobranchs and Pulmonates
(Euthyneura) by the mere shortening and concentration of
the untwisted loop. This view derives support from the
fact that the persistent ctenidium retains its primitive posi-
tion on the right side of the body in Opisthobranchs, while
in Prosobranchs it shows a marked displacement and lies
on the left side. Bouvier's observations on Actceon
( = Tornatella), however, have completely altered the posi-
tion of affairs. Actceon is a very primitive Opisthobranch,
as may be inferred from the high development of its shell,
the persistence of its operculum, and the absence of pleuro-
podial fins. Bouvier tell us (4) that Actcson resembles the
Prosobranchs, not only in these points, but also in possess-
ing a distinct twist of the visceral loop (streptoneurism,
chiastoneurie). The ctenidium is innervated from a supra-
intestinal ganglion, which lies on the left side of the body.
We are accordingly led to the conclusion that the
euthyneurous condition of Opisthobranchs and Pulmonates
has not been directly inherited from the orthoneurous
ancestors of the Gastropoda, but has been derived from a
previously streptoneurous condition. In other words the
Opisthobranchs and Pulmonates have descended from
Prosobranch ancestors, and the right-sided position of the
gill-plume in Opisthobranchs is not primitive, but the result
of a secondary process of detorsion.

Orthoneuroidism. — Without going further into the
matter it may also here be mentioned that the supra-in-
testinal commissure has been recently discovered in various
species of Nerita, Neritina, and Navicella by Boutan (2),
Bouvier (3^), and Haller (11) — a discovery which de-
stroys the last refuge of orthoneurism in Prosobranchiate
Gastropods. Streptoneurism may now be affirmed of all
Prosobranchiate Gastropods.

Origin of the Moliuscan nervous system. — The attempts
of previous writers to explain the relations of the nervous
system of Mollusca have been based almost exclusively

THE MORPHOLOGY OF THE MOLLUSC A. 55

upon comparisons with the fully constituted nervous
systems of such types as the Turbellaria and Annelida.
With Thiele's theory of the Turbellarian ancestry of the
Mollusca I have already dealt, and I do not propose to
deal with the Annelidan hypothesis, since this theory can-
not provide any satisfactory explanation of the high develop-
ment of the pleuro-visceral nervous system of the Mollusca.
Those authors who, like Thiele and Pelseneer, homologise
both the pleural and pedal centres of the Mollusca with the
ventral cords of Annelids, base their view upon the sup-
posed origin of the pleural centres from the pedal cords.
This derivation I have already shown in this article to be
completely erroneous. Pelseneer's theory of the origin of
the Mollusca from Polychsete ancestors (18a), and all
theories which seek the origin of the Mollusca in the
specialised representatives of any of the vermiform groups,
may at once in my opinion be dismissed from considera-
tion.

Apart from matters of minor importance it will, I think,
be conceded that the following cardinal points in regard
to the morphology of the Molluscan nervous system have
been established by the facts and arguments which have
been presented in this article : —

(1) That the pleural ganglia have not been derived by

segregation from the ventral or pedal cords.

(2) That the pleural, visceral, and abdominal ganglia

of Gastropoda form a group of dorsal nerve-
centres — the two former owing to their dif-
ferentiation in the immediate neighbourhood of
the velum, and the latter owing to its differentia-
tion from the mid-dorsal wall of the body (floor
of mantle-cavity).

(3) That the dorso-lateral nerve-ring of Amphineura

is primitive and is represented in other groups
of Mollusca by both the pallial and visceral
nerve loops, or their derivatives.

(4) That the sub-intestinal position of the visceral loop

in all groups except the Amphineura is a
secondary one, which has been rendered possible

56 SCIENCE PROGRESS.

only by the decentralisation of the primitive
pleuro-visceral nervous system, and its separa-
tion into special ganglia and nerves, the latter
being formed ontogenetically as fibrous out-
growths from the ganglionic centres.
Venturing now, in conclusion, upon more speculative
ground, I believe that the embryonic relations, to which I
have drawn attention, between the pleural and visceral
ganglia and the ciliated band are of phylogenetic importance.
It has long puzzled me that the larval forms (trochospheres) of
two groups so closely allied as the Annelida and Mollusca,
while presenting a close similarity in general structure,
should differ so remarkably in regard to their nervous
system. The Annelid trochosphere has a nerve-ring
beneath its ciliated band, while the Molluscan trocho-
sphere has none. In this respect the Molluscan trocho-
sphere appears to be less primitive than that of the
Annelida. The explanation of this now appears to me to
be as follows. In the evolution of the Annelida the proto-
troch and nerve-ring remained for a long time unmodified,
and did not share in the elongation of the postero-ventral
region of the body which gave rise to the trunk of the
Annelid. This would explain the absence of the dorsal
nerve-ring in the adult Annelid, provided that the nerve-
ring, together with the prototroch, came to have merely a
larval significance, — as actually happens in the ontogeny of
Annelids to-day. On the other hand, in the evolution of
the Mollusca from the same simple type of ancestor, the
whole body must have shared in the elongation — the proto-
troch and nerve-ring as well as the more ventrally placed
parts of the body. This elongated nerve-ring I identify
with the pleuro-visceral ring of Amphineura, although the
phyletic connection between the nerve-ring and the ciliated
band is inferred from the development of certain Gastro-
pods rather than from the Amphineura themselves. As a
larval adaptation for conveniences of natation I imagine
that a separation became gradually effected in embryonic
life between the ciliated ring and the nerve-ring, the former
becoming restricted to the anterior end of the larval body,

THE MORPHOLOGY OF THE MOLLUSC A. 57

while the latter became more and more extended pari passu
with the elongation of the trunk. Such a separation is to
some extent paralleled in the development of Holothurians
from the Auricularia larva, as described by Semon. On
this theory alone can I explain to myself the absence of the
ancestral nerve-ring in the trochospheres of Mollusca, and
I find some support for this view in the ontogeny of Nemer-
tines. The lateral nerve-cords in this group have the same
relation to the gut and brain as have the pleuro-visceral
cords of Chiton, since they form a dorso-lateral ring, the
posterior commissural portion passing above the rectum.
In Nemertines there can be very little doubt that this
nerve-ring has been derived phyletically by the elonga-
tion of a nerve-ring which underlay the ciliated band of a
more or less Pzlidzum-like ancestor, as it underlies the
ciliated band of the Pi/idzum-laxva., although this phyletic
origin is disguised by the profound metamorphosis which
breaks the continuity of the ontogenetic record in Nemer-
tines. On this theory of course the lateral cords of Nemertines
do not correspond to the ventral cords of Annelids. The
latter are represented by the general ventral plexus of
Nemertines and by the pedal plexus or cords of Mollusca.
These ventral nervous systems appear to bear relations to
the dorso-lateral ring-nerve similar to those of the subum-
brellar plexus of Medusae to the circumferential nerve-ring.
It will be recognised from these remarks that the
conclusions to which I have arrived present distinct points
of agreement with those of Balfour (1, p. 37&) and Sedg-
wick (21) on the same subject, although attained throughout
by an independent series of inductions. With both these
writers I agree in tracing back the Molluscan nervous
system to a primitively annular type, such as might be
expected to exist in a Ccelenterate ancestor. Balfour
derives the whole Molluscan nervous system from a
peripheral nerve-ring which followed the course of a hypo-
thetical ciliated ring: ; Sedgwick derives it from a broad
plexus surrounding an elongated blastopore, such as occurs
in existing Actinians. Sedgwick's theory was practically
an alternative to Balfour's, but I find myself able to give a

5» SCIENCE PROGRESS.

partial acceptance to both these views. For the nervous
system of Mollusca appears to me to consist of two parts, a
circumferential ring and a peri-blastoporal plexus. The
circumferential ring, which was primitively associated with
a ciliated ring, is represented by the pleuro-visceral nervous
system, which I have shown to possess significant relations
with the velum or prototroch of the larva ; and the peri-
blastoporal plexus seems to me to be recognisable in the
pedal nervous system, which in primitive Molluscs has a
very diffuse plexus-like arrangement, and in Amphineura,
at any rate, reveals its peri-blastoporal character in the
cerebro-pedal connectives in front and its connectives with
the supra-rectal abdominal ganglion behind.

BIBLIOGRAPHY.

(i) Balfour, F. M. Comparative Embryology, ii., 1885.

(2) BOUTAN. Arch. Zool. Exp. (3), i., pp. 221-265, 1893.

(3) Bouvier. Systeme Nerveux des Prosobranches. Ann. Sci.

Nat. (7), iii., 1887.
{id) Bouvier. Comptes Rendus, cxiv., p. 1281, 1892.

(4) BOUVIER. Comptes Rendus, cxvi., pp. 68-70.

(5) Duvernoy. Mem. sur le systeme nerveux des Mollusques

Acephales. Mem. Acad. Sci. Paris, xxiv.

(6) ERLANGER, R. von. Zur Entwicklung der Paludina vivipara,

I. u. II. Theil. MorpJi. Jahrbuch, xvii., 1891.

(7) ERLANGER, R. VON. Zur Entwicklung von Bithynia ten-

taculata. Mitth. Zool. Stat. Neapel. x., 1892.

(8) HALLER, BELA. Die Organisation der Chitonen der Adria.

Arb. Zool. Inst. Wien, 1882-3.

(9) HALLER, BeLA. Untersuchungen Liber marine Rhipido-

glossen, I. Morph.Jahrb., ix., 1884.

(10) Haller, Bela. Die Morphologie der Prosobranchier. Morph.

Jahrb., xiv., 1888.

(11) HALLER, BELA. Studien liber Docoglosse u. Rhipidoglosse

Prosobranchier, 4I-0, 1894.

(12) HUXLEY and PELSENEER. Report on Spirula. "Challenger"

Reports, Zool, part lxxxiii., Appendix, 1895.

(13) KERR, J. G. On some Points in the Anatomy of Nautilus

pompilius. Proc. Zool. Soc, part iii., 1895.

(14) Korschelt u. Heider. Lehrbuch der Entwicklungs

geschichte, iii., 1893.

THE MORPHOLOGY OF THE MOLLUSC A. 59

(15) KOWALEVSKY, A. Embryogenie du Chiton polii. Ann. Mus.

Hist. Nat. Marseille., Zool., i., 1883.

(16) LANG, ARNOLD. Lehrbuch der Vergl. Anat, 3 heft.

(17) Lankester, E. Ray. Mollusca. Encycl. Brit., ninth

edition.

(18) PELSENEER. Contribution a l'etude des Lamellibranches.

Arch, de Biol., xi., p. 166, pi. vi., fig. 3, 1891.
(i8#) PELSENEER. Classification Generale des Mollusques. Bull.
Sci. France et Belg., xxiv., p. 346, 1892.

(19) PELSENEER. Introduction a l'etude des Mollusques. Bruxelles,

1894.

(20) PLATE. Bemerk. lib. d. Phylogenie u. d. Entstehung d.

Asymmetrie d. Mollusken. Spengel's Zool. Jahrbiicher, Abth.
f. Anat. u. Ont., ix., i., p. 169, 1895.

(21) Sedgwick, Adam. On the Origin of Metameric Segmenta-

tion. Quart. Jour. Micr. Sci., xxiv., 1884.

(22) SlMROTH. Bronn's Klassen u. Ordnungen des Thier-Reichs .

Mollusca. I. Amphineura u. Scaphopoda, 1892-94.

(23) Thiele, J. Ueber Sinnesorgane der Seitenlinie und das

Nervensystem von Mollusken. Zeit.f. IViss. Zool, xlix., pp.
385-432, 1890.

(24) Thiele, J. Die Stammesverwandschaft der Mollusken. Jena

Zeit., xxv., p. 480, 1 89 1.

(25) Thiele, J. Beitrage zur Kenntniss der Mollusken. Zeit. J.

Wiss. Zool, liii., p. 578, 1892.

(26) WlLLEY, A. Natural Science, vi., p. 412, 1895.

Walter Garstang.

THE RESERVE MATERIALS OF PLANTS.

( Concluded. )

THE position of the glucosides in vegetable metabolism
has been for a long time a subject of considerable
controversy, which has, however, been most largely con-
cerned with tannin. The details of its formation, its locali-
sation and its fate have been discussed at great length, but
the discussion has been largely conducted on the lines of
hypothesis and analogy rather than experiment. The con-
clusions reached by such a method of treatment have some-
what hastily been applied to all glucosides, as if tannin were
eminently the typical one. There are now reasons for
thinking that so far from this being the case it is especially
exceptional.

The number of oflucosides known has increased con-
siderably in recent years as our investigations into plant
metabolism have been pursued, and increasing knowledge
of them forces the conviction more and more upon us that
they take a more or less active share in the nutritive pro-
cesses, possibly direct, but more probably through certain
of the products to which they give rise on decomposition.
They are not so markedly reserve stores for seeds as are
many of the bodies we have already discussed, though many
seeds, and notably many of those of plants of the Rosaceae
and Cruciferse and orders allied to these, contain them in
quantity together with other reserves. They occur, how-
ever, in other parts of the plant, not quite as circulating
reserves, but rather as transitory stores for more localised
growth and nourishment. The old advocates of their
nutritive functions rested their case largely on the presence
of sugar in the glucoside molecule, and held that this is the
body which is available for the constructive processes of the
organism. There are, however, reasons for holding that
this view is too limited a one. and that some of the other
products of their decomposition may be as valuable as the
sugar, if not of even greater importance.

THE RESERVE MATERIALS OF PLANTS. 61

The glucosides that have attracted most attention during
recent years are those which occur in the plants belonging to
the families already mentioned, the Rosacese, the Cruciferae,
and other orders which show affinities with these. These
plants contain, very widely distributed through their tissues,
amygdalin and sinigrine or myronate of potash respectively.
Of these the former is perhaps the most interesting, as
from its decomposition by enzyme agency there is produced
hydrocyanic acid, which has always been regarded as most
virulent in its action upon all living things. The existence
of this noxious principle in the plant has perhaps been partly
the cause of the readiness of botanists to class the glucoside
which yields it, and hence the whole class of glucosides,
among the products of excretion.

The localisation of the amygdalin is calculated to throw a
good deal of light upon the question of its probable function
and fate. For many years attention has been given to it,
at first, owing to imperfect methods of research, without
much practical result. Improvement in technique has,
however, yielded very valuable results, and has led to
conclusions greatly at variance with those held thirty
years ago. Thome (60), who wrote in 1865 upon the
nutritive materials contained in the sweet and bitter al-
monds respectively, said that amygdalin occurs in the
parenchyma of the cotyledons of both varieties, and that
its corresponding enzyme, emulsin, is only present in the
bitter almond, being localised in the weak fibrovascular
bundles that are in the cotyledons. This statement has
been shown to be the exact converse of the truth. Portes
(61), who worked twelve years later, showed that the gluco-
side and the enzyme occupy different parts of the seed, the
former being distributed in the cotyledonary parenchyma,
while the latter is to be found in the axis of the embryo.
Pfeffer (62), in his Pflanzenphysiologie, suggests that this
localisation is not accurate, and that the two bodies probably
occupy the same cells, the only degree of separation being
that the ferment is in the protoplasm and the glucoside dis-
solved in the cell-sap. In 1887 Johansen (63) by chemical
methods succeeded in ascertaining the distribution of the

62 SCIENCE PROGRESS.

two bodies in the seeds. He found the emulsin to be pre-
sent in both varieties of the almond, and to be chiefly
localised in the fibrovascular bundles. He further ascer-
tained that the glucoside, amygdalin, is only present in the
cotyledonary parenchyma of the bitter one. The absence
of the glucoside from the seed of the sweet almond points,
of course, to the conclusion that even if it be a nutritive
body it is not one of very great prominence in the nutrition
of the embryo on germination.

Guignard has published within the past few years a
series of researches which deal primarily with the localisa-
tion of the enzymes which decompose the glucosides, but
which incidentally throw a certain light upon the occurrence
and meaning of the latter. In his first papers (64) he treats
of the amygdalin which is found in the almond and in the
cherry laurel, in the latter of which it is found to have a
fairly copious distribution. He confirms Johansen as to its
position in the seed of the almond, and still more closely
localises the enzyme. In the laurel (Prunus lauro-cerasus)
the parenchyma of the leaves as well as of the axis appears
to contain it in solution in the cell-sap. The occurrence of
the emulsin is confined to the neighbourhood of the con-
ducting- tissues, it being chiefly found in the endodermis
round the fibrovascular bundles. In the bundles of the axis
of the embryo in the almond the ferment occurs in the many
layered pericycle, chiefly outside the bast. The distribution
of the amygdalin is not definitely known. It may happen
that the fluid sap containing it may travel along the cellular
tissue, and the occurrence of the ferment which decomposes
it, in the immediate neighbourhood of the conducting tissues,
suggests that it is charged with the duty of preparing from
the glucoside certain nutritive products that may easily make
their way to the conducting tissues, and so travel to the
actual seats of constructive metabolism. That sugar so
travels is of course a matter of every-day experience, but
whether or no the remaining products are made use of in a
similar way is open to discussion. On the other hand it
may be that the amygdalin descends by the conducting
tissue of the bast and undergoes decomposition as it passes
downwards, yielding simpler products to the young cortex.

THE RESERVE MATERIALS OF PLANTS. 63

In the face of the problem of the utilisation of the bodies
resulting from the action of emulsin upon amygdalin great
importance must be ascribed to the recent work published
by Treub on the occurrence and meaning of hydrocyanic
acid in the tissues of Pangium edule (65), one of the
Bixacese. This compound, according to the author, does
not occur as a glucoside, but in the free condition, and is
present in relatively large amount. Greshoff found more
than 1 per cent, to be hydrocyanic acid of the dry weight
of the plant in one sample among many others analysed.
A brief resumi, of the author's conclusions seems not to be
out of place here, as throwing light upon the question of
the nutritive value of the glucoside of the laurel. Indeed
it seems not improbable that the hydrocyanic acid itself may
be regarded as, in some cases at least, a reserve material.

Treub has made a careful investigation into the
localisation of this principle in the plant, using as his
method the reaction given in the formation of Prussian
blue when hydrocyanic acid comes in contact with a ferric
salt in the presence of hydrochloric acid. The reaction is
very distinct and takes place well in the interior of the
cells, causing those which contain the hydrocyanic acid
to stand out with great distinctness.

In the whole of the adult axis, both stem, root and
peduncles, he finds it to exist in quantity in the conducting
tissue of the bast and pericycle. In the leaves it is still in the
same regions, but is more widely spread, nearly all the
parenchymatous tissue of the blade containing more or less
of it. The epidermis especially is noteworthy, showing it
present in the basal cells of the hairs which the leaves bear,
and in certain idioblasts which contain also crystals of
oxalate of lime. In the young fruits and those which are
growing a considerable quantity is present, partly in the
bast and partly in parenchyma outside the conducting tissue.
In the seeds there is an accumulation in the peripheral
layers of the endosperm and in other cells of the same
tissue abutting on the embryo.

In these regions, and in the cortex, and sometimes the
pith of the axis, Treub describes the hydrocyanic acid as

64 SCIENCE PROGRESS.

existing in special cells which are sharply marked off from
the others round them when stained as above described.
These special cells vary a good deal in number, apparently
according to the amount of the acid present in the plant,
and have no very specially regular distribution. Indeed it
seems probable that any cell of the tissue may become a
centre of deposition of the acid. Generally, if not quite
isolated, they only occur two or three together. Certain of
the fibres of the pericycle may be observed almost similarly
isolated.

Treub further says that these special cells of the cortex
or of the pith derive their supply of hydrocyanic acid from the
conducting tissue of the bast and that the amount of them
and consequently of the acid varies with the condition of
the stem.

Tracing the hydrocyanic acid upwards through the axis
by means of longitudinal sections it can be found to extend
throughout its whole length, but to disappear at a little dis-
tance from the growing point, the apical meristem of which
contains none.

It is impossible to avoid being struck with the similarity
here exhibited to the fate of sugar, amides, etc., which as
we have seen can be traced up to the seats of constructive
metabolism and there cease, apparently giving rise to
protoplasm. If this be so, the hydrocyanic acid must be
regarded as a plastic material, unsuitable as at first sight it
would appear for that purpose.

This view is supported by several observations which
the author details at some length. He finds that in the
apices of young shoots which have suffered an arrest of
growth, there are more of the special cells containing the
hydrocyanic acid than there are in similar ones which are
undergoing rapid elongation. That is, where there is active
consumption of plastic material there is no accumulation of
the acid, but where plastic substances are compelled to remain
unused, hydrocyanic acid is one of such stored bodies.

Another series of observations considerably strengthens
this view, while it points more definitely to the ultimate
purpose of the acid. In many of the special cells the latter

THE RESERVE MATERIALS OF PLANTS. 65

may be seen to be accompanied by quantities of proteid
substance. Taking young cells near the apex of the shoot
the special cells contain the hydrocyanic acid alone, showing
that it precedes proteid in the time of its occurrence. A
little farther back the proteid can be detected, and gradually
as sections are taken at increasing distances from the apex
it increases in amount while the acid diminishes. As the
active life of the cells becomes less and less vigorous, the
proteid becomes more and more preponderating in the cell
contents, and ultimately cells are found which contain
proteid only, the hydrocyanic acid having all disappeared.
The same succession of events can be seen if the develop-
ment of the pericyclic fibres be traced towards the apex of
the stem.

There seems from these observations to be very strong
reasons for supposing that hydrocyanic acid is a nutritive
substance and leads at any rate in these plants to the
formation of proteid.

Treub holds that this is its immediate function ; he
believes it to be primarily formed in the leaves, principally
in the basal cells of the hairs and the idioblasts with calcic
oxalate in the epidermis of the leaves. Thence it makes
its way to the conducting tissues of the bast and pericycle
and travels to the apical meristems. It is thus primarily a
body originating only in the constructive processes, and not,
as in the cases of the almond and cherry laurel, the product
of a decomposition of a glucoside. Indeed Treub says very
emphatically : " L'acide cyanhydrique du Pangium edule
n'est pas un produit de decomposition ou de desassimila-
tion," basing the statement on both indirect and direct
arguments. The former are founded on the localisation of
the product in the bast and pericycle and its evident trans-
portation by the bast tissue. The latter involve the
consideration of its localisation with a material which
serves as a temporary proteid reserve in the same elements
of the tissues, and the order of appearance and disappear-
ance of the two substances in such special cells.

That hydrocyanic acid can subserve not only the for-
mation of temporary reserves of proteid but can be used,

5

66 SCIENCE PROGRESS.

immediately after its first formation, by the leaves in which
it is formed also appears certain. When plants whose
leaves contain it are put for some days in the dark the acid
gradually disappears, and as usual in such cases their whole
metabolism suffers. On being again illuminated the vital
processes gradually resume their activity. If a plant be
put in the dark till nearly all the acid has gone from
the leaves and then it be brought into the light, the little
that remains is soon removed by the returning activity of
the metabolism.

That the acid is used, and not simply transported from
the leaves, can be shown in another way, by cutting a
circular section through the conducting tissue of the petioles,
when removal by transport becomes impossible. Yet the
hydrocyanic acid disappears gradually.

It was said above that in some cases the hydrocyanic
acid itself might be looked upon as a reserve material.
This seems to be the case in the special cells described by
Treub in the cortex of plants when they do not contain
also proteid. In such cases we seem to have temporary
reservoirs to supply local and transitory needs and to
supplement the current passing along the bast. " Dans
les endroits non on pas suffisamment desservir pour le
systeme conducteur liberien ces usines locales prennent
naissance, et en plus grand nombre, a mesure que la
plante a on aura besoin dans ces endroits de plus de
substances plastiques." Thus in the older part of the
stem, where the active life is confined almost altogether
to the cortex, the latter contains many of these special cells,
while they are absent from the rest of the fundamental
tissue. Where they are present, as in certain portions of
the petioles, active life continues, although it may be de-
cadent in other parts.

This temporary storage comes out very prominently in
the cases of the developing fruit and seed. At the base of
the former, just above its point of junction with the pedicel,
there is a very marked accumulation of the hydrocyanic acid,
the cells staining blue under the treatment described being
much more numerous than lower down the stalk. The

THE RESERVE MATERIALS OF PLANTS. 67

peripheral layer of the seed in its young condition is
also supplied very fully with these local reservoirs. We
appear to have here a deposit laid down to supplement the
regular stream which is passing all about the plant by means
of the conducting tissue of the bast. It is doubtless derived
from the circulating supply, for if the latter be interrupted
by a section passing across the stem through its path, the
disappearance of the acid takes place from the bast tissues
below the wound some time before it does from the isolated
special cells of the cortex.

From the work of Treub and of Guignard then it seems
increasingly probable that the glucosides are reserve
materials, and not simply bye-products or products of
excretion. Nor is it apparently only the sugar in them
which has a nutritive value, but the other products of their
decomposition have a particular part to play in the meta-
bolism. This is certainly the case with hydrocyanic acid,
and no doubt further investigation will show that it is the
same with other products similarly formed.

Guignard (66, 67) has made similar researches to those
already described upon the plants of the natural orders
Cruciferae, Capparidaceae, Tropceolacese, Limnanthaceae,
Resedaceae and Papayaceae ; which all contain the ferment
myrosin, a body capable of decomposing more than one
glucoside. There are several of the latter compounds
found in this group of plants, the best known of which are
sinio-rine, ancj sinalbine. Siniorine is found in the black
mustard (Brassica nigra), and is often called myronate of
potassium. On decomposition it yields besides sugar a vola-
tile body, sulphocyanate of Allyl, and potassic hydrogen
sulphate. Sinalbine, as its name implies, is found in the
white mustard (Sinapis or Brassica alba). When decom-
posed the volatile constituent is found to be sulphocyanate
of orthoxybenzyl. Others, the composition of which is not
yet fully known, are those of the watercress {Nasturtium
officinale) which yields phenyl propionic nitrile, the common
cress {Lepidium sativum) affording the nitrile of alpha-
toluic or phenylacetic acid. Though the fate of these
complex volatile bodies has not been investigated, it is

68 SCIENCE PROGRESS.

noteworthy that some of them at any rate contain cyanogen
compounds, which may well be utilised after the manner of
hydrocyanic acid itself as established by Treub.

Their distribution in the plants appears to follow that of
the amygdalin in the Rosaceous group, but very little
definitely is known on this head. The enzyme which splits
them up is according to Guignard always found in special
cells which do not contain the glucoside.

Very closely allied to the group of the glucosides is
that of the tannins, about the importance of which there
has been a good deal of controversy. Some of them are
no doubt glucosides, yielding among their products of de-
composition gallic acid and sugar. Others are apparently
not so associated with a carbohydrate group. They are
very widely distributed, and often occur not only in parts of
plants which are devoted to storage of materials, but in the
tissues where active metabolic work is going on. The
task of deciding whether or no they serve as reserve
materials or as bye-products is consequently not easy.

The two views have been strenuously supported by
different writers. Sachs, while working on the germination
of the Scarlet-runner (68) in which tannin is comparatively
plentiful, suggests an antithesis between carbohydrates
and proteids on the one hand, and the tannins and colour-
ing matters on the other, the latter being in his opinion
only bye-products. He advances in support of his view the
fact that they appear or increase with renewed growth of
the embryo, instead of diminishing as reserve materials
should do. Their appearance is coincident with the chemical
changes in the undoubted reserves which lead to the
utilisation of the latter. The same view is advanced by
Schell (69), who suggests that in some cases, however, it
may be a nutritive product. In the germination of certain
oily seeds, chiefly of plants belonging to the Boroginaceae,
tannin, which is present in addition to the oil, diminishes
in quantity during the germination. In the stem of the
mature plant there is during the winter a considerable
quantity of tannin which almost vanishes as spring ad-
vances. On the other hand he finds in certain almost parallel
cases that the tannin accumulates instead of diminishing.

THE RESERVE MATERIALS OF PLANTS. 69

The view that these bodies have a nutritive value has
been supported with some emphasis by other writers.
Wigand associated it very closely with the carbohydrates,
and thought it was an essential factor in vegetable meta-
bolism. Wiesner also supported the view of its carbohy-
drate relationships, and indicated a probability that it stands
between the starch and cellulose groups and the great class
of resins, etc. The latter relationship has been again
brought forward by Hillhouse (70), who found in Pinus
sylvestris that as resin increases in the stem tannin dimin-
ishes in like proportion, and that the cells surrounding the
resin ducts invariably show its presence. Hartig suggests
that tannin remains in the oak through the winter in the
form of grains similar to starch grains, but distinguishable
from the latter by characteristic reactions. These grains,
he says, are dissolved and utilised in the spring. In his
later writings Sachs inclines to the same view ; he says
that besides those which must be looked upon as excreta or
bye-products, some of the tannins of the oak are most likely
to be regarded as reserve products, on account of their origin
and disappearance and their behaviour generally during the
growth of the plant (71).

The localisation of tannin in the different parts of the
plant does not give us much assistance in determining which
of these views has most to support it. It is often found in
special sacs in the midst of metabolic tissues ; it is very
frequently found in epidermal cells, either in the interior or
saturating the cell wall ; it is extremely prominent in bark.
These positions certainly suggest that it is of but little value
as a food-stuff; on the other hand it is often abundant in
assimilating parenchyma in which starch formation is pro-
ceeding.

In Hillhouse's paper (70) already alluded to, the author
describes a considerable number of observations he made to
determine whether or no a disappearance or diminution of
tannin could be detected in the spring, and if so, whether it
was a reasonable conclusion that such diminution indicated
a utilisation of the vanished portion.

He investigated a large number of trees in which tannin

70 SCIENCE PROGRESS.

is present in greater or less amount, and noted the changes
in the amount present in winter and in spring in their various
tissues. He concludes that in no case is there noticeable a
diminution of tannin in early winter as starch accumulates,
and there is no sign that the starch is formed at the expense
of the tannin. When growth recommences in the spring,
instead of tannin disappearing from the older tissues it makes
its appearance in quantity depending on the amount of
growth. The tissues of the bud are commonly crowded
with it. Hillhouse's experiments proceeded upon three
lines. In the first place plants or parts of plants rich in
tannin were made to grow under conditions in which assim-
ilation of C02 was impossible ; a second set of experi-
ments consisted of germinating in darkness seeds containing
tannin ; and finally corms were investigated to see whether,
as their nutritive material was transported to the newly-
formed corm springing from them, tannin was transferred
together with the starch.

In no case was any diminution or transference found,
except in the case of Pinus sylvestris already alluded to,
when the probability of the tannin being an antecedent of
the resin became evident.

Those tannins which are undoubtedly glucosides must,
however, be of some nutritive value, as they give off sugar
on decomposition taking place. There is some evidence to
show that during the ripening of certain fruits part of the
sweetness is derived from an astringent principle resembling
and probably identical with tannin, which diminishes in quan-
tity as the fruit matures (72).

A similar uncertainty as to its physiological meaning
must for the present be associated with phloroglucin and
the compounds into which it enters, which are to be re-
garded as ethers corresponding to glucosides. There are
two classes of these compounds, which have been described
as phoroglucides and phloroglucosides respectively. The
former include such bodies as hespentine, phloretine, etc.,
while the latter, which contain a sugar group in their for-
mula, embrace aurantine, rhamnine, hesperidine, etc. They
are somewhat difficult to localise, as the reactions they give

THE RESERVE MATERIALS OF PLANTS. 71

are either not well ascertained or not particularly distinctive.
The most reliable is perhaps that with vanilin in the pre-
sence of hydrochloric acid. When this is made to react
upon a cell which contains phloroglucin in the sap, the
latter forms a fine precipitate of red granules which are
composed of a compound of vanilin and phloroglucin, known
as phloroglucivanilni.

Phloroglucin appears to be often present in the plasma
of meristem cells rather than in the vacuole, for when chlo-
ride of vanilin is added to a tissue containing it the colouring
mainly affects the protoplasm, some of the vacuoles remaining
altosfether uncoloured.

The distribution of phloroglucin, like that of tannin,
leaves a good deal of uncertainty as to its physiological
meaning. It has been investigated in recent years by
Waage (73), who has carefully examined representative
plants taken from almost all sections of the vegetable
kingdom. Out of 185 plants submitted to experiment
135 showed it to be present, but in very different quan-
tities. Of the 135, 51 contained a very considerable
quantity, 41 less but still a tolerably large amount,
while in 43 though present only a feeble reaction could
be obtained. Its distribution was to a certain extent
regular, for the author states that if one species contains
it, it is found with tolerable certainty in all the species of
that genus. The plants of the Polypetalae as a rule show
most, while the Gamopetalae and the Monocotyledons are
on the whole poor in it ; lower down in the scale the Vas-
cular Cryptogams and the Gymnosperms are charged with
it to a degree intermediate between the other groups.

Examining the tissues of such plants as contain a con-
siderable quantity it may be found in meristems and in
permanent tissues. In axial organs it occurs in the
epidermis and later in the bark ; also in the parenchyma
of the cortex, and in the sclerenchyma of the tissues more
deeply seated. It is found sometimes in the endodermis ;
also in the dead cell walls of the xylem parenchyma, fibres,
and vessels. The medullary rays frequently contain a
certain quantity. It is uniformly absent from the bast

72 SCIENCE PROGRESS.

fibres and the sieve tubes, and may be present or not in
the pith. When the epidermis contains it, it is usually
in the hairs if any are present ; even root-hairs giving
evidence of a certain amount. Taking the members of the
axis, Waage found that roots as a rule contain more than
stems, unless the latter be rhizomes, in which it is fairly
abundant. Petioles and the peduncles of flowers contain
less than branches. In plants where the axis is highly
charged with it, there is generally a quantity also recog-
nisable in the leaves, chiefly occurring there at the edges
near the endings of the veins, and further in the neighbour-
hood of the vessels of the latter. The palisade tissue of
the leaf has usually more than the spongy mesophyll, and
the upper has more than the lower epidermis. The seed
as a rule contains but little, and that is only in the integu-
ments.

If the disposition may be taken as any indication of
its being a reserve material at all, the probability is that its
value in the latter sense is but slight. The disposition of
varying amounts in the medullary rays and its frequent
presence in the cells of the cambium layer point possibly
to its supplying nutritive material for the latter. On the
other hand, its consistent absence from all parts of the seed
except the integuments seems to indicate that storage of
nutriment is not its main purpose. It may be that its value
to the meristem tissues is based upon its easily oxidisable
character, affording energy thereby, rather than being a
reserve substance. Its occurrence in the leaves in the
localities named suggests a formation in the mesophyll and
a subsequent transport to the axial regions. But against
the view of its value in metabolism as a reserve material
we have the statement that light does not affect its forma-
tion. It is in Waage's opinion found in the cell-sap as a
general rule, rather than in either protoplasm or choro-
plastids. It seems on the whole to be a product of
destructive metabolism, for it occurs in the same cells as
starch and sugar and may be derived from the latter by
abstraction of three molecules of water, C6HI206 - 3 H20 =
C6H6Q3. It seems to resemble tannin in that it often

THE RESERVE MATERIALS OF PLANTS. 73

increases with the greater development of the plant, and in
being frequently plentiful in parts that are thrown off from
the latter, such as old leaves, the coats of fruits, seeds, etc.,
and in regions withdrawn from active metabolism, such as
bark and to a less degree epidermis. In a further paper
Waage and Nickel suggest that it may possibly be a source
of tannin, as the latter is generally found in the same
parts as phloroglucin (74). Tannin does not appear, how-
ever, to give rise to phloroglucin.

Like tannin, therefore, phloroglucin appears to be on the
whole an accessory product and only rarely to act as a
reserve material. The compounds of it which contain
sugar, i.e., the phloroglucosides, may serve as such, yielding
sugar on their decomposition.

In certain cases the alkaloids appear to serve as reserve
materials, though their value in this direction is probably
but slight. Many seeds which contain them in some con-
siderable quantity lose them during germination, and other
bodies, principally amides, replace them in the developing
embryo or young seedling. This is especially the case with
the seed of Lathyrus Sativus, an Indian species which
contains sometimes as much as '5 per cent, of its dry
weight of an alkaloidal product known as viciine (75).

The possibility of alkaloids helping in such cases to
form albuminoid materials or proteids has been pointed out
by Jorissen (76) in his discussion of the chemical processes
incident to germination, in which he claims for them a
certain value as reserve materials. Heckel [jj) comes to
the same conclusion. He carried out experiments with
Sterculia acuminata, Strychnos Nux-vomica, Physostigma
venenostim, and Datura Stramonium, and found in all these
cases that during germination the greater part of their
alkaloidal principles disappears. He claims that this
disappearance is due to a transformation into assimilable
substances under the influence of the embryo. If the
latter be extracted from the seeds, and they be then sur-
rounded by or buried in moist earth, the alkaloids remain
for a considerable time unchanged.

The conclusions of Jorissen and Heckel are disputed by

74 SCIENCE PROGRESS.

Clautriau (78), who finds another explanation of the dis-
appearance of the alkaloids during germination in a possible
destruction of them as deleterious bodies which would
affect prejudicially the development of the young seedling.
He has ascertained with considerable precision the dis-
tribution of the alkaloid in the seeds of Atropa Beliadona,
Datura Stramonium, and Hyoscyamus Niger, and states
that it is confined entirely to a layer of cells situated
between the albumen and the integument of the seed, which
when the latter is mature is very much reduced in its
dimensions. This layer is much more prominent while the
seed is ripening, consisting of many cells with very rich
contents, the latter consisting of starch and albuminoid sub-
stances as well as alkaloids. As the albumen grows, this
nourishing layer gradually yields up both starch and pro-
teids, while the alkaloid persists ; the cells become
gradually nearly empty, and dry up considerably, ultimately
becoming dead. In this condition they still contain the
alkaloid, the quantity of which does not diminish during the
changes described. When the seed is mature, this layer
is very thin, the cells being flattened and compressed to-
gether, forming a sort of membrane in which the alkaloids
remain, partially or wholly combined with an organic acid.

The nutritive value of the alkaloid seems improbable
when we consider the disappearance from this layer of the
starch and proteids, and the retention of the former. If it
were then a reserve product it would in all probability ac-
company the other undoubted nutritive bodies. Clautriau
has obtained further information on this point by depriving
seeds of Datura Stramonium of this alkaloidal layer and
submitting them to germination, either in moist earth or in
an atmosphere saturated with watery vapour. He found
that under such conditions they germinated normally, and
produced young seedlings which differed in no particulars
from normal seedlings of Datura.

Clautriau extended his researches to other plants than
those named, particularly Conium maculatum, from which
he obtained the same results.

Examining the young seedlings grown under these

THE RESERVE MATERIALS OF PLANTS. 75

conditions, no alkaloid being allowed to remain in the seed,
Clautriau found that the active principle made its appear-
ance in considerable quantity, and chiefly in thegrowingapices.
The same thing was noticeable in the development of mor-
phine in the poppy (79), where a more gradual formation
was detected. Morphine does not show itself at the out-
set of the development of the plant, but appears to be
preceded by another alkaloid, giving very clear reactions,
which does not seem to be identical with any of the nitro-
genous principles extracted from opium.

The conclusion that must be drawn from these investiga-
tions is that these alkaloids, and hence probably all such bodies,
are not to be regarded as reserve materials, but as bye-
products or excreta, appearing coincidently with the active
metabolic processes of the growing plant.

Besides these accumulations of more or less complex
organic compounds in the tissues of plants we meet with
certain cases where inorganic material is deposited with a
view to subsequent utilisation. These are, however, of
much less importance and only occur in comparatively few
plants. We have the well-known globoids in the aleurone
grains of the castor-oil seeds, the seeds of Bertholletia
excelsa and several others. From their disposition and
fate, and from the fact that they afford a supply of phos-
phorus, it is probable that we may include them in this
group. In certain cases also the collections of crystals of
calcium oxalate gradually disappear from the cells in which
they are deposited, and so seem to minister to the needs of
the plant for calcium, an element whose function, however,
is still practically unknown.

BIBLIOGRAPHY.

(60) Thome. Ueber das Verkommen des Amygdalins und des

Emulsins in den bittern Mandeln. Botanische Zeitung, p.
240, 1865.

(61) PORTES. Recherches sur les amandes ameres. Journal de

pharmacie et de chimie, t. xxvi., p. 410, 1877.

(62) PFEFFER. Pflanzenpkysiologie, t. i., p. 307, 1881.

(63) JOHANSEN. Sur la localisation de l'emulsine dans les aman-

des. Ann. des. Sc. Nat. Bot., 7 ser., t. vi., p. 118, 1887.

76 SCIENCE PROGRESS.

(64) GuiGNARD. Sur la localisation, dans les amandes et le

Laurier-cerise, des principes qui fournissent l'acide cyan-
hydrique. Journal de pharmacie et de chimie, 5 ser., t. xxi.,
pp. 233-289, 1890.

(65) Treub. Sur la localisation, le transport, et le role de l'acide

cyanhydrique dans le Pangium edule Reinw. Ann. du
Jardin Botanique de Buitenzorg, xiii., p. 189, 1895.

(66) GuiGNARD. Recherches sur la localisation des principes

actifs des Cruciferes. Journal de Botanique (March), 1890.

(67) GuiGNARD. Recherches sur la nature et la localisation des

principes actifs chez les Capparidees, Tropeolees, Limnan-
thees, Resedacees, et Papayacees. Journal de Botanique,

1893-

(68) SACHS. Ueber die Keimung von Phaseolus multiflorus.

Sits, der Wien Akad., 1859.

(69) Schell. Physiologische Rolle der Gerbsaure. Bot. Jalires-

berlcht, 1875.

(70) HlLLHOUSE. Some Investigations into the Function of Tannin

in the Vegetable Kingdom. Midland Naturalist, 1887-8.

(71) SACHS. Vorlesungen iiber PJlanzenphysiologie, 1882.

(72) BuiGNET. Ann. Chemie Phys., ser. iii., Bd. 61, 1861.

(73) Waage. Ueber das Vorkommen und die Rolle des Phloro-

glucins in der Pflanze. Ber. d. dent. bot. Gesell., November,
1890.

(74) Waage and NICKEL. Zur Physiologie des Geitstoffs und der

Trioxybenzol. Bot. Central., 1891.

(75) RlTTHAUSEN. Journ. Jur pract. Chem., new series, vol. xxiv.,

p. 202, 1 88 1.
(j6) JORISSEN. Les phenomenes chimiques de la germination.
Memoires couronncs de I' Acad. Royale de Belgique, lxxxviii.,

P- 73-

(77) HECKEL. Sur l'utilisation et les transformations de quelques

alcaloi'des dans la graine pendant la germination. Comptes
Rendus, January, 1891.

(78) Clautriau. Localisation et signification des alcaloides dans

quelques graines. Ann. de la Societe beige de Microscopie
{Memoires), t. xviii., 1894.

(79) CLAUTRIAU. Recherches microchimiques sur la localisation

des alcaloi'des dans le Papaver somniferum. Mem. de la Soc.
beige de Microscopie, t. xii.

J. Reynolds Green.

jj L I » & A R Yj 3u

AFRICAN GRASS FIRES AND THEIR^ m + £V

EFFECTS. N& V >^

MANY parts of the interior of tropical Africa consist
of wide grassy plains, occasionally varied by
scattered trees, but usually very bare and monotonous in
appearance. In the rainy season these steppes are green
with vigorously growing grass, and patrolled by hundreds
of antelopes and other kinds of game ; a few months after-
wards when the rains are over, they are covered by
blackened ashes and charcoal, and not a living creature will
be visible except perhaps a few birds or a very occasional
ground-rat.

These fires are usually due to the natives, who find
that the bush can be most easily cleared by their assistance,
though they are often lighted to satisfy the childish delight
in a big blaze which is characteristic of the Suahili porter.

Their effects are most interesting, both economically
and also in the way in which they entirely change the
aspect of the vegetation.

It is, of course, immediately obvious that all the valu-
able feeding material of many square miles of luxuriant
grass is by these fires entirely wasted ; but, besides this,
the soil is never permitted to grow rich through the
accumulation of leaf-mould and stems, and in fact the land
is every year brought back into exactly the same condition.
No true turf is formed, and the soil remains more like the
subsoil in cultivated countries and never becomes in the
least improved.

The effect on the vegetation is very curious. The
season of flowering for many trees and herbaceous
plants is completely altered. A large number of low-
growing herbaceous plants possess woody root-stocks or
some sort of underground store of nourishment. With the
very first shower of the rainy season, these stores send up
flowering stems entirely without leaves, and the bare and
blackened earth is studded with the bright purple flowers of

78 SCIENCE PROGRESS.

Dolichos spp., the blue Pentanisia Schweinfurthii, little
white Euphorbias, Lasiosiphon spp., etc. These all have
the appearance of a flower cut off and planted in the earth,
and give rise to remarks on the collector's carelessness in
not bringing leaves when worked up by untravelled
botanists. With the setting in of the rains, the stems
begin to grow and produce leaves until, when the grass has
sprung up, all these herbs are in full foliage. This habit is
of great advantage to the flowers concerned, as insects
can readily perceive the scattered flowers which in the grass
would be quite inconspicuous. The same thing occurs in
many of the trees. Several species of Dombeya, for example,
send out their flowers at this foreshadowing- of the rains
and are most conspicuous.

Another curious effect of the fires is the manner in
which trees are either kept down or obliged to protect
themselves in some way against their action. In the more
arid plains trees seldom exist, or if present occur in the
form of stumps perhaps ten years old, but never able to
grow higher than a foot or so. Such stumps put out every
wet season vigorous shoots, which are annually burnt away
and only the short stem with another layer of wood is left
to survive.

Of the trees which do manage to exist in spite of the
annual conflagration, the most remarkable are the tree
Euphorbias, often twenty to twenty-five feet high. These
have angular fleshy branches protected by a leathery
epidermis, and besides their milky juice, which contains
gum, caoutchouc and other substances, have a large amount
of mucilage or slimy matter in the ordinary tissue. This
latter is a strongly waterholding substance, and the most
violent fire seems unable to do more than scorch a very few
of the outermost branches.

It is a most curious fact that though when living they
resist fires in this wonderful manner, dead branches make
an excellent fire and blaze up most vigorously. I cannot
understand this difference.

Of the other trees which continue to thrive in these
places, there are some seven species which grow in abun-

AFRICAN GRASS FIRES AND THEIR EFFECTS. 79

dance ; there will be usually 500 of one of these species to
every individual of some other kind. I brought home
specimens of the bark of these six or seven forms, which
were given to Professor Bretland Farmer for examination,
who replied as follows : " I examined your specimens of
bark and they all agree in possessing cells which show a
certain amount of gummy degeneration of the cells in the
bark, together with the presence of a considerable amount
of sclerotic cells ; it seems not impossible that these two
facts may be connected with the resistance of the plants to
the fires, and I found as a matter of fact that, on comparing
the rate of burning of these barks with that of laburnum,
they were very slowly consumed.

" I should have added that there are repeated periderms,
and intermixed with the cork are the sclerotic cells
already mentioned." Now the artificially produced cork
of commerce shows great similarity in some respects to
the cork of these fireproof trees. The process adopted
both with the birch and the cork oak is to carefully peel off
the cracked superficial layer of bark or " male cork " (this is
known as "demasclage"). After this the layer of cork
increases enormously and may perhaps attain to 17 cm.
in thickness if left untouched : the result is the ordinary
commercial article. I do not think that it is going too far
to say that we have in grass fires a natural " demasclage "
process, for they will certainly destroy the outer more or
less dead tissues.

From the researches of Henslow,1 Tschirch2 and
Volkens 3 on desert plants, it may be considered proved
that cutin, which most modern authorities consider nearly
identical with suberin, is directly increased by dry and arid
conditions, so that this direct effect is probably also of
use in increasing the deposition of corky matter. Both
evils — -the fire and the drought — have, as so often happens,
brought about their own remedy. The sclerotic cells (or stone
cork ?) may doubtfully be set down to the same cause, for

1 Origin of Plant Structures.

2 Angewandte Anatomie and Linnea, 1881.

3 Flora der egypt. arab. IVuste.

80 SCIENCE PROGRESS.

culture experiments (Duchartre and Henslow, loc. cit., p. 57)
show that sclerenchyma may be directly diminished by a
more moist atmosphere.

The occurrence of gum is not so clearly dependent on
the climatic conditions ; its use in these forms is, however,
obvious enough, for all apertures by which water might be
lost are, so to speak, gummed up. This is quite similar in
physiological action to the drops of mucilage or gum which
hermetically seal the vessels exposed by cutting across a
branch of any ordinary deciduous tree.

It is true that the production of gum is known to be
most abundant in a dry and hot season, but according to
the explanation given by Tschirch, loc. cit., p. 2 1 1 (and an
identical account has been given me by Mr. Malcolm Dunn
as the result of experience), this is due to the gum being
squeezed out by the contraction of the bark following on a
wet period, during which the masses of gum in the bark
are greatly swollen. I cannot find any explanation of the
actual cause of the change of cellulose into gum, but Mr.
Malcolm Dunn states the general opinion that it is abundant
after a severe shaking of the trees, as, for example, in a violent
wind. Such places as those here treated of are certainly
exposed to wind (otherwise they would be covered by
forest, according, that is, to my experience), and it is possible
that the wind may have assisted in starting gum formation ;
but if, as is not unlikely, the wind acts indirectly by straining
the layers of the cell walls, it seems more probable that the
fierce heat of the fire, causing sudden and violent shrinking
and warping of the bark, strains the cell walls in the same
manner. This may of course be quite unproved, but the
facts are sufficiently interesting to justify further research.

G. F. Scott Elliot.

Bcimce progress.

No. 26. April, 1896. Vol. V.

THE GENERAL BEARINGS OF MAGNETIC

OBSERVATIONS.

IF necessity be the surest prompter of invention, it is not
too much to say that the necessity of the navigator
has been a most potent factor in producing the observer of
the elements of Terrestrial Magnetism. The traveller on
land might rest during darkness until daylight enabled him
to resume his journey ; but the seaman on the trackless
ocean was dependent upon the indications of his compass
by day and night ; and after the discovery of Columbus
that the magnetic Declination or Variation of the needle
from the direction of the geographical North varied in
amount with the Latitude and Longitude, a new impetus
was given to observation.

The publication of Gilbert's grand discovery that the
earth is a magnet and the director of the freely suspended
needle, followed by the discovery of the secular change in
the value of the Declination, naturally added to the desire
of both landsmen and seamen to know as much as possible
concerning that great magnet, both from purely scientific
reasons and to meet the practical ends of the navigator.
Thus the seventeenth and eighteenth centuries were re-
markable for the number of observers both of the magnetic
Dip and Declination.

So important had a correct knowledge of the Declination

become to the requirements of navigation, as early as the

close of the seventeenth century, that Halley, under the

6

82 SCIENCE PROGRESS.

immediate auspices of the Government, made his celebrated
voyage over the Atlantic Oceans in a man-of-war, in order
that intelligent observation should set at rest much that was
doubtful. The results of this voyage, combined with the
observations of previous navigators, were embodied in his
celebrated chart of lines of equal value of magnetic Varia-
tion or Declination, the first of its kind and of so convenient
a form that charts of equal values of the three magnetic
elements are to this day the most acceptable form for
representing the combined results of magnetic observations
made over large areas of sea and land, as well as of the
special magnetic surveys which in recent years have been
made in various countries.

Here we may pause to consider the word Declination as
applied to the angle which the direction of the horizontal
magnetic needle makes with the true meridian. Many
magneticians object to the word, but no better has yet been
proposed or at any rate accepted ; the result being that
while observers on land use the term, seamen adhere firmly
to the expression "Variation of the Compass". This is as
might be expected when it is remembered that navigators
look upon the word Declination as connected with the posi-
tion of the sun and other heavenly bodies, and would find it
most inconvenient to have the same word in daily use,
meaning two totally different things.

During the eighteenth century charts of the magnetic
Declination were published by Mountaine and Dodson,
Bellin, and Churchman, and for their time may be con-
sidered as fair approximations to the truth. Churchman's
design was not only to give values of the Declination but
to furnish the seaman with a means of ascertaining the
Longitude, an ambitious project, especially as we now
know there were probably considerable elements of error
in these charts caused by local magnetic disturbance of the
observing compass on land, and from the iron used in con-
struction disturbing the compass on board the ships.

This latter source of error was only beginning to be
viewed in its true light at the close of the eighteenth
century.

THE BEARINGS OF MAGNETIC OBSERVATIONS. 83

In the years 1801-2 Commander Flinders of H.M.S.
Investigator, then surveying the southern coasts of Australia,
found that when his vessel's head was north or south by
compass the observed Declination agreed very nearly, but
when she lay with her head east or west, it differed largely.
Moreover these errors on the east and west points of the
compass had the opposite sign to those observed in Eng-
land.

Flinders, however, had supplemented the existing
scanty knowledge of the distribution of the Dip over
navigable waters by several observations of his own in
northern and southern latitudes, and from these he drew
the conclusion that the errors in the Declination observed
on board ship were caused by magnetism induced by the
earth in the vertical iron of the ship, and changed in value
proportionally to change of Dip. Here Flinders was wrong,
as the errors were really proportional to the tangent of the
Dip.

In spite of this mistake he was enabled from his know-
ledge of the Dip to conceive the idea of so placing vertical
bars of iron that they produced an equal and opposite effect
on the compass to that of the ship in all latitudes, and thus
invented what is now called the Flinders bar, one of the
most important correctors of compass disturbance in the
iron and steel ships of the present day.

In 1 8 14 Flinders induced the Admiralty to have ex-
periments made on board men-of-war at Portsmouth,
Sheerness, and Devonport, to ascertain the amount of the
magnetic disturbance of the compass caused by the iron in
each ship. The chief reason for making these experiments
was to show the necessity for ascertaining and applying
these errors to ensure the safe navigation of the ships, but
it had also a direct bearing in enabling observers to elimi-
nate the hitherto inexplicable divergencies in the values of
the Declination observed in different ships in the same
geographical position. The results of these experiments
bore no immediate fruit, for with the death of Flinders the
subject was temporarily neglected.

In 1 8 19, Hansteen published his Magnetismus der Erde

84 SCIENCE PROGRESS.

with an atlas containing charts of the elements Declination
and Dip for different epochs between the years 1600 and
1787. These charts were in a large measure compiled from
observations made with imperfect instruments and subject
to the causes of error already mentioned attending both land
and sea results. Hansteen, however, considered them of
sufficient value to enable him to draw certain important con-
clusions with regard to the cause of the secular change of
the magnetic elements. Thus he not only concurred with
Halley that the earth considered as a magnet had four
poles or points of attraction, but computed their geo-
graphical positions. Further than this, he computed that
to account for the secular change these four supposed
poles revolved round the terrestrial poles, each pole
occupying a widely different number of years to complete
the revolution.

If these theoretical results had been true, a great
advance would have been made not only in the science
of terrestrial magnetism but in its practical bearing on the
requirements of the present day.

Although Humboldt had about the year 1800 shown
that the intensity of the earth's magnetism varied with the
latitude, the general distribution of that magnetic element
was so little known that we may with our present extended
knowledge consider that Hansteen's conclusions were based
on insufficient data. In fact the idea of the earth being a
magnet with four poles has long since been abandoned in
favour of there being one pole with two foci of intensity in
each hemisphere, and reasons will be given further on
which tend to throw doubt on there being any revolution of
these two magnetic poles round their adjacent terrestrial
poles.

Subsequently to Hansteen's charts there appeared those
of the Declination by Yeates, Duperrey, and by Barlow in
1836. These were useful to navigation but helped very
little towards the solution of the problem of the ever vari-
able distribution of the earth's magnetism.

Besides this by the year 1835 the iron-built ship had
appeared on the ocean and a correct knowledge of the

THE BEARINGS OF MAGNETIC OBSERVATIONS. 85

three magnetic elements became a necessity in solving the
problems which the magnetism of different iron ships
presented.

With Gauss's invention of the absolute horizontal force
magnetometer in 1833, many hitherto unknown move-
ments of the magnetic needle of the highest interest were
discovered, which with the coarser instruments previously
in use lay concealed. This discovery gave the desired
impetus to the scientific men of that epoch, and the period
included in the years 1835-45 was "a time of unparalleled
activity in the extension of systematic and accurate mag-
netical observations over the earth's surface ".

Whilst most of the continental nations joined in this
movement, the principal share in the work was divided
between Germany, Russia, and England in Europe, and the
United States in America. But before the splendid series
of simultaneous observations made on the continent, and
four British colonial observatories were organised, Gauss
in 1839 published his general theory of Terrestrial Magnetism
coupled with a series of charts of the three magnetic elements
for the whole world, based upon observations made at
ninety-two selected stations distributed over the earth's
surface ; and it may be remarked that Gauss's charts not
only gave results in fair accordance with observation in
explored regions, but also as afterwards proved in Antarctic
latitudes hitherto unvisited by man.

The proof came in the years 1839-43, when Ross's
Antarctic voyage of exploration was carried out in the
interests of terrestrial magnetism. Besides the importance
of a knowledge of the general distribution of the magnetic
elements in those regions, one great aim of this expedition
was to reach the south magnetic pole. This was found to
be impossible, but sufficient data were collected to give its
approximate position. Whilst this Antarctic magnetic
survey was being completed, that of British North
America was also undertaken with the result of the deter-
mination of the locality of one of the foci of greatest
intensity in the northern hemisphere.

The results of these surveys formed, as will be well

86 SCIENCE PROGRESS.

remembered, a valuable series of "contributions" to terres-
trial magnetism by Sabine, and, coupled with every available
observation between the years 1818 to 1876, formed the
materials for the series of charts entitled " The Magnetic
Survey of the Globe " for the epoch 1842*5. Each map
gave normal lines of equal values of the Declination, In-
clination and Intensity. Although it may be said that from
the Arctic circle to the Antarctic, the direction of the lines
was efficiently given by observation, the lines within those
circles were largely taken from Gauss's computed lines
modified to agree with observation.

Another difficulty in compiling these charts of Sabine's
with accuracy lay in the uncertain knowledge of the secular
change then available, and which had to be applied to
observations made so far apart in time.

Sabine's charts are doubtless the best we have for the
epoch 1842*5, but in the light of the requirements of
modern science they leave much to be desired as regards
the Antarctic regions. The observations south of 6o° S.
were made entirely on board ships, where the errors of the
compass sometimes exceeded 50° due to the horizontal
forces in the ship, thus rendering accurate observations of
the Declination very uncertain and correction of the observed
Inclination very difficult ; besides which there are no
records of the ship's disturbing force in the vertical direc-
tion.

Naval requirements, however, did not permit of any
delay in publishing magnetic charts affecting navigation,
for in 1846 the Hydrographer of the Admiralty requested
Sabine to provide charts of the Declination for the Atlantic
Oceans from 6o° N. to 6o° S. These were largely used until
Evans's chart of the Declination for the whole navigable
world was issued in 1858.

The excellent work of Flinders already referred to, of
ascertaining from his knowledge of terrestrial magnetism
the chief cause of the deviation of the compass in wood-
built ships, and providing a corrector for those deviations,
had to be followed up on a much larger scale and with
more exact methods in the iron-built ship, which, in that

THE BEARINGS OF MAGNETIC OBSERVATIONS. 87

period of activity in terrestrial magnetic science — 1835-45 —
was rapidly increasing in numbers on the ocean.

Thus in 1835 observations were made on board iron
ships showing that they acted as a magnet on their com-
passes, but there was nothing to show in the results what
the causes of this condition of the iron ship were, until
Poisson in 1838 published his celebrated "Memoir on the
deviations of the compass produced by the iron in a ship ".
This was a rigorous mathematical investigation of the
subject, showing that the deviations of the compass were
due to induction in the ship by the magnetic force of the
earth.

If the iron ship had simply been built for service in one
locality, a limited knowledge of terrestrial magnetism would
have sufficed to elucidate the causes of her magnetic con-
dition ; but she was destined to traverse every navigable
sea over large changes of magnetic latitude, hence the
necessity for an accurate knowledge of the distribution of
magnetism over the great parent magnet, in order to
determine the magnetic condition of her comparatively
minute offspring the magnetised iron ship ; and this at all
times and in all places in the interests of navigation.
Observations of the terrestrial magnetic elements were
therefore an absolute necessity if iron-built ships were to be
substituted for those of wood.

The ability to predict the deviation of the compass on
change of latitude did not, however, satisfy Airy, for after
a remarkable mathematical investigation of iron ship's
magnetism of a less rigorous character than Poisson's, but
sufficiently accurate for his purpose, he in 1839 proposed
his methods of annulling the deviation of a ship's compass
by means of magnets and soft iron, so arranged as to pro-
duce equal and opposite magnetic effects to that of the
ship. Provided with Airy's admirable and simple directions
this method of correction was comparatively easy in one
latitude, but experience at sea, especially in voyages to the
Cape of Good Hope, showed that every iron ship required
a different application of Airy's correctors.

To discriminate between the amount that was to be

88 SCIENCE PROGRESS.

corrected by permanent magnets, by horizontal soft iron,
and by vertical soft iron, an accurate knowledge of the
magnetic elements Dip and Intensity obtained from obser-
vations on land and at sea was essential.

Before dismissing the subject of the above application
of magnetic observations, it may be remarked that we have
now heavily armed, protected steel cruisers steaming over all
parts of the world with less change of deviation of the
compass than the wood-built Erebus and Terror of Ross's
Antarctic expedition, and this remarkable result could not
have been achieved if the terrestrial magnetic observer had
not done his work.

Moreover, if magnetic observations are not continued
the secular change of the magnetic elements will soon
commence to mar the precision with which our rapidly
moving ships traverse the globe.

The voyage of the Challenger in 1872-76 contributed
the most valuable series of observations of the magnetic
elements in modern times, when the large areas of the
principal oceans traversed by that vessel during three and
a half years are taken into consideration. These observa-
tions, combined with those taken from every available
source, both British and foreign, between the years 1865-87,
formed the materials from which the magnetic charts of
1880 were compiled (see vol. ii., Physics and Chemistry,
part vi., Voyage of H.MS. "Challenger").

The Challenger only crossed the Antarctic circle at one
point in longitude 78° EM and, therefore, although we know
large secular changes to be going on south of 400 S. we have
no measure of the amount, nor anything like an accurate
knowledge of distribution of the earth's magnetism in those
regions. This points to the necessity for a new Antarctic
expedition.

In the year 1888 the late Professor J. C. Adams was
provided with a complete set of magnetic charts for the two
epochs 1842-5 and 1880 previously mentioned, and as it
was known he had directed his profound mathematical
ability to the analysis of the results contained in them, it
was hoped that some new and important light might be

THE BEARINGS OF MAGNETIC OBSERVATIONS. 89

thrown upon the bare facts presented. His lamented death
occurred without his publishing any results.

If, however, reference be made to the report on the
magnetical results of the Challenger, a discussion of the
secular change is contributed founded in a great measure
on a comparison of those charts. The outcome of this
discussion is to throw considerable doubt upon the theory
that the motion of the magnetic poles round the terrestrial
is the cause of secular change ; in fact, that the magnetic
poles remain fast, and we must look elsewhere for the cause
whatever it may be.

Magnetic observations have so far been considered in
their all-important bearing as necessary to safe navigation
in wood-built ships, and in a far higher sense as indispens-
able to that of the iron- or steel -built ships which now
cover the ocean ; the magnetic charts hitherto generally re-
quired for these purposes being those on which normal
lines of equal values have been given, but something more
is now needed.

Observation in comparatively recent years has shown
that not only are there large " regional " magnetic dis-
turbances extending over large areas of land, but that in
moderate depths of water where the largest ship can navi-
gate freely, the land below is also found to have considerable
areas of local magnetic disturbance which, if not allowed for,
may in thick or foggy weather lead ships into danger by
seriously disturbing their compasses.

The United States have done excellent work in pro-
ducing charts of iso-magnetic lines, or charts in which the
chief local magnetic disturbances are recognised, and the
full results of observation recorded. The maonetic sur-
veys of Riicker and Thorpe in the British Isles, of Moureau
in France, of Rijckevorsel in Holland and elsewhere, have
thrown considerable light on the magnetic conditions of
those countries, but there remain whole continents to be
covered by the observer.

The direction of the iso-magnetics too from the deep
sea to the dry land of the coasts is an extension of the
subject, which the observer has hardly touched as yet, but

go SCIENCE PROGRESS.

one affecting the safety of navigation, as well as the question
that has been raised, whether the water areas of the globe
are as a whole more, or less magnetised than the land areas.

To possess charts of iso-magnetic lines for even a few
countries is an evidence of considerable advance in the
knowledge of terrestrial magnetism, for if reference be
made to Sabine's lines of intensity in his contribution on
the magnetic survey of North-West America it will be
found that he rejected certain observations he considered
abnormal and defective, which Lefroy the observer con-
sidered to be his best and naturally retained in his map ;
the result being a considerable difference in the form of the
curves adopted by the two magneticians, Sabine giving
normal curves, Lefroy iso-magnetics.

Respecting the local disturbances of the needle which
have been so clearly proved, the question naturally arises,
whence the cause of these disturbances ? It is now believed
by many, if not finally accepted, that Rlicker and Thorpe
have answered the question by the results of their laborious
survey of the British Isles, coupled with Riicker's elegant
investigations as to the permeability of specimens of the
rocks taken from the localities in which magnetic dis-
turbances were found. Their answer is to the effect that
these disturbances, which have been found to extend over
a region 230 miles long by about 110 miles broad, are
due to induction by the earth's magnetism in rocks of dif-
ferent permeability, either present as in the basalts on the
surface or concealed by superficial deposits.

These results are distinct from the extraordinary dis-
turbances of the needle when in the immediate vicinity of
permanently magnetised rocks, and when the radius of dis-
turbance may be only as many feet as the extent of the
regional disturbance is in miles.

The points of interest in the question of regional
magnetic disturbance are not confined to the magnetician,
for the geologist cannot afford to neglect the valuable in-
formation the magnetic needle affords. Thus although
Rlicker and Thorpe have since made a second and more
elaborate survey of the British Isles, their remark of 1890

THE BEARINGS OF MAGNETIC OBSERVATIONS. 91

that "the kingdom can be divided into magnetic districts
in which the relations between the direction of the disturb-
ing forces and the main geological characteristics are so
suggestive as to be worthy of careful statement and further
investigation," not only holds good, but has received con-
firmation.

The mining engineer is deeply interested in a know-
ledge of the Declination. Charts of normal lines are of
great use to him whether above or below the earth's surface,
but especially below when he has no other guide. To such
an one a knowledge of regional magnetic disturbance as de-
duced from surface observations is most important, as it
tells him that he is in the neighbourhood of magnetic
rocks, the disturbing effect of which on his compass needle
may be far greater in the depths of his mine and turning it
into a treacherous guide.

We have now considered magnetic observations in a
measure from the point of view of the immediate practical
results which their scientific treatment produces, but who
will say in this great maritime nation that the work of mag-
netic observers, even if solely to make navigation poss'ble,
is not worthy of the fullest consideration ?

There is besides a vast field of inquiry for the observer of
terrestrial magnetism in unravelling thesecretsof the earth con-
sidered as a magnet, and the ceaseless change of its magnetic
condition which the needle tells us of, for which no immediate
practical result can be foreseen, yet is worthy of the attention
of the ablest physicists and most advanced mathematicians.

Inquiry into the causes of the secular change is one
requiring the fullest attention, but observation has not yet
done sufficient work. It certainly has done much in certain
countries, and for a large portion of the world as regards
secular change in the past, and data obtained for predicting
future changes for a few years, but only one expedition has
examined the Antarctic regions magnetically, and it is
doubtful if any substantial progress will be made until a
second expedition is made thither, one profiting by the
experience of its precursor, and equipped with possibilities
for work hardly hoped for by Ross.

92 SCIENCE PROGRESS.

It may be remarked in passing that a remarkable
alteration in the amount of the secular change has been
noticed in the Declination and Inclination at the following
observatories : Bombay, Batavia, and Hong Kong about
the period of the eruption of Krakatoa in 1883. This may
be only a coincidence, but may it not also point to the
possibility that the changes below the surface of the earth
which culminated in that mighty explosion, and may still
be at work, have had, and continue to have, magnetic
effects which are recorded by the needles at those observa-
tories ?

Critical investigations have for many years been directed
to the elucidation of the causes of the observed diurnal
variations of terrestrial magnetism. This work was long
seriously retarded by the various methods adopted at different
observatories for recording their results, obliging those who
entered upon a comparison of such results to go through a
tedious conversion of them into a common method. It may
be said that the first large departure from this objectionable
practice occurred when the International Polar Inquiry of
1882-83 was undertaken by the various expeditions.

This was an important step in the right direction, but
there remains much to be done, as shown by the ten re-
ports of the British Association Committee on "the best
means of comparing and reducing magnetic observations ".
Their last report consists of an able and suggestive paper
by Dr. Chree, being the analysis of the results of five years'
observations on "quiet days" at Kew, and is well worthy
of attention as indicative of the present state of our know-
ledge as regards the diurnal variation of the three magnetic
elements.

Such investigations only encourage one in the hope that
the much required observations in southern latitudes may
be undertaken. The observatories at the Cape and Mel-
bourne could do invaluable work if it were carried out on
the lines of Kew, for example.

Lastly, what more is there to be said about magnetic
observations and their bearings ? We do not know why
the earth is a magnet, the cause of the secular change of its

THE BEARINGS OF MAGNETIC OBSERVATIONS. 93

magnetism, why it is subject to solar diurnal, lunar diurnal,
sidereal diurnal and the other variations and disturbances,
nor the cause of magnetic storms, although we can observe
connections between them, earth currents, and aurorae.
Whether the causes of all these exist below the surface
of, or are external to, the earth, or are a combination of
the two, has still to be learnt, and it seems hardly too much
to hope that the restless needle will sooner or later be the
means of opening up sources of knowledge invaluable to
cosmical science, as well as to those only concerned with the
planet upon which they dwell.

When the causes of the secular change are understood
there will be no difficulty in providing the navigator with
magnetic charts for years in advance, much as the tides can
now be tabulated for his use. In the latter case observa-
tion has done its work for several frequented ports, in the
former case a vast amount remains to be done, and the
word that goes forth is still, as Lord Kelvin thrice said
on a kindred subject connected with ships' magnetism,
" Observe".

Ettrick W. Creak.

THE PRESENT POSITION OF THE CELL-
THEORY.

PART I.

A FEW years ago a discussion of the cell-theory would
have seemed superfluous. To-day, partly because
of criticisms which have been directed against the theory,
partly because of the great increase of our knowledge re-
specting cell-structure, the advantage and even the necessity
of such a discussion will be admitted by everybody who has
read and reflected on the subject. In what follows, I
propose to examine the cell-theory in the light of recent
criticisms and researches. I set out with the intention of
avoiding anything in the shape of polemical writing, but I
fear that I have in places fallen away considerably from the
course which I had proposed. In a much disputed subject
controversv is inevitable, a circumstance which need not be
regretted, for controversy is the whetstone of argument, and
obliges those who engage in it to be doubly careful both of
their facts and of the language in which they express them.
My antagonists will, I hope, give me the credit of the
desire to deal fairly with their arguments and criticisms, and
will acquit me of unnecessary bitterness. It has been my
object to elucidate the subject in hand rather than to try to
gain a dialectical advantage.

It is advisable, before entering on the examination, to
have a clear conception of what the cell-theory really is.
This is the more necessary because one of its most recent
critics, Mr. Adam Sedgwick, has complained than nobody
will define the theory in an exact manner ; it is, he says, a
kind of phantom which takes different forms in different
men's eyes. I have shown in another place that this state-
ment is hardly fair, because there are some authors whose
researches on cytology entitle them to speak with authority
who have recently defined the cell-theory in a very precise
manner, though it may be conceded that there are biologists

THE PRESENT POSITION OF CELL-THEORY. 95

whose views are not so exact, and who habitually commit
themselves to statements which on careful examination may
prove to be altogether untenable.

It was pointed out some time since by Whitman,1 and I
have since emphasised the fact,2 that in his broad generalisa-
tions Schwann defined the cell-theory in a very exact manner,
and that the words originally used by him are perfectly
applicable to the cell-theory as it has been held up to the
present time. In saying this, I do not forget that Schwann
held some very erroneous views as to the nature and
structure of cells, which he regarded as vesicles, filled with
fluid, which made their appearance in a structureless matrix,
named for this reason, a cytoblastema. But Schwann's
work consisted of two parts, a statement of observations,
which have proved to be entirely erroneous, and a theory
of organisation, which has been very fruitful of results. He
was careful to say that his theory was only a provisional
explanation which suited the facts as nearly as possible, and
it is a great merit of the theory that it afforded such an in-
sight into organisation that the essential part of it did not
cease to be serviceable long after the "facts" on which it
was founded were shown to be, for the most part, false.
We need not therefore concern ourselves with the fact that
Schwann's conceptions of the origin and structure of cells
were false, but we may examine his theory and see how
much of it we may hold to, and how much we must reject
at the present day.3

Schwann was a very cautious writer, and the quotations
which are given below will dispose effectually of the state-

1 C. O. Whitman, "On the Inadequacy of the Cell-theory of Develop-
ment, "Journal of Morphology, viii., p. 639, 1893.

2G. C. Bourne, "A Criticism of the Cell-theory," Quart. Jour. Micro-
scopical Science, xxxviii., p. 137, 1895.

3 A large part of Schwann's theory of cells, viz., that part of it which
compared cell-formation to the process of crystallisation, was soon shown
to be untenable. But as this part was based on his erroneous views on
the structure and origin of cells, I have passed it over, since the falsity of
his views on this subject involved the falsity of as much of his theory as
was founded on them.

96 SCIENCE PROGRESS.

ment which stands in the first paragraph of Whitman's
work, that he believed that in cell-formation lies the whole
secret of organic development. There are, says Schwann,
two possible theories on the subject of organic development:
(i) The organism theory, namely, that there is an inherent
power modelling the body in accordance with a predominant
idea. (2) The physical theory, namely, that the funda-
mental powers of organised bodies agree essentially with
those of inorganic nature. Rejecting the former of these
two theories as being outside the domain of physical science,
Schwann went on to write : x " We set out with the sup-
position that an organised body is not produced by a
fundamental power which is guided in its operation by a
definite idea, but is developed according to the blind laws
of necessity by powers which, like those of inorganic
nature, are established by the very existence of matter.
As the elementary materials of organic nature are not dif-
ferent from those of the inorganic kingdom, the source of
the organic phenomena can only reside in another com-
bination of these materials, whether it be in a peculiar
mode of union of the elementary atoms to form atoms of
the second order, or in the arrangement of these con-
glomerate molecules when forming either the separate
morphological elementary parts of organisms, or the entire
organism. We have here to do with the latter question
solely, whether the cause of organic phenomena lies in the
whole organism or in its separate elementary parts. If
this question can be answered a further inquiry still re-
mains as to whether the organism or its separate elementary
parts possess this power through the peculiar mode of
combination of the conglomerate molecules or through the
mode in which the elementary atoms are united into con-
glomerate molecules."

Is it not perfectly clear from this that Schwann fully
recognised that there was a further question underlying

xTh. Schwann, Microscopical Researches into the Accordance in the
Structure and Growth of Animals and Plants. Translated by Henry
Smith. London: Printed for the Sydenham Society, 1847.

THE PRESENT POSITION OF CELL-THEORY. 97

the cell-theory, and do not the words which he used with
regard to the union of elementary atoms to form atoms of
the second order show a prescience of the assumptions
which would have to be made to explain the powers mani-
fested by cells ? Because he confined himself to the one
question, it is not fair to say that Schwann had not a clear
appreciation of the importance of the other. I may relate,
in this connection, an anecdote which will finally clear
Schwann's reputation from the reproach fastened upon it.
Professor Lankester tells me that about the time when a
sort of jubilee was held in Schwann's honour at Liege in
1878, he was introduced to him, and ventured to ask in
the course of conversation how it was that after the publica-
tion of his famous essay he had so long been silent.
Schwann answered that he had not been idle, but that
ever since he had been unsuccessfully occupied in trying to
find out the secret of the constitution of the cell.

To return to the question propounded by Schwann,
does the cause of organic phenomena lie in the organism or
in its separate elementary parts, the cells ? He answers
very decidedly, in the separate elementary parts, and gives
the following reasons for his answer: " All organised
bodies are composed of essentially similar parts, namely, of
cells ; these cells are formed and grow in accordance with
essentially similar laws, and therefore these processes must
in every instance be produced by the same powers. Now
if we find that some of these elementary parts not differing
from the others are capable of separating themselves from
the organism and pursuing an independent growth, we may
thence conclude that each of the other elementary parts —
each cell — is already possessed of the power to take up fresh
molecules and grow, and that therefore each elementary
part possesses a power of its own, an independent life, by
means of which it would be enabled to develop itself in-
dependently if the relations which it bore to external parts
were but similar to those in which it stands in the organism.
The ova of animals afford us examples of such independent
cells apart from the organism."

A little further on he says : " In inferior plants any given

7

98 SCIENCE PROGRESS.

cell may be separated from the plant and can grow alone.
So that here are whole plants consisting of cells which can
be positively proved to have independent vitality. Now as
all cells grow according to the same laws, and consequently
the cause of growth cannot in one case lie in the cell, and
in another in the whole organism, and since it may be
further proved that some cells, which do not differ from the
rest in their mode of growth, are developed independently,
we must ascribe to all cells an independent vitality, that is
such combinations of molecules as occur in any single cell
are capable of setting free the power by which it is enabled
to take up fresh molecules. The cause of nutrition and
growth resides not in the organism itself but in its separate
elementary parts. . . . The manifestation of the power
which resides in the cell depends upon conditions to which
it is subject only when in connection with the whole or-
ganism."

The whole theory is very succinctly summed up in the
following passage : " The elementary parts of all tissues are
formed of cells in an analogous though very diversified
manner, so that it may be asserted that there is one uni-
versal principle of development for the elementary parts of
organisms, however different, and that this principle is the
formation of cells ".

No doubt objection may be taken to-day to the uni-
versality of this statement, but if we modify the last part
of it and read " that the most general principle of develop-
ment for organisms, however different, is the formation of
cells," we shall have very nearly expressed the truth, as we
know it at the present day.

I have found it necessary to quote Schwann's work at
considerable length, and to repeat more emphatically what
I stated in my previous essay on Epigenesis and Evolution.1
Dr. Whitman,2 in a reply which deals partly with my

1 G. C. Bourne, "Epigenesis and Evolution," " Science Progress,"
vol. i., 1894.

2 C O. Whitman, Evolution and Epigenesis. Boston : Ginn & Co.,
1895.

THE PRESENT POSITION OF CELL-THEORY. 99

criticisms, and partly with the much more weighty argu-
ments brought forward at the same time by Dr. Oscar
Hertwig, says that my criticisms, in so far as they are
directed against the inadequacy of the cell-theory of develop-
ment, are largely the result of misunderstanding ; this may
in part be true, but I cannot have misunderstood the simple
meaning of his first paragraph, and I wish to insist on the
fact that the cell-theory, as it was promulgated by Schwann,
did not regard cell-formation as the whole secret of organic
development, and that the cell was not, in the mind of the
author of the cell-theory, the alpha and omega of both
morphological and physiological research in the animal
kingdom. If this is clearly understood at the outset, it will
help to remove much possible misunderstanding.

But, as Mr. Sedgwick has rightly said, we have to deal
not only with what its authors thought, but with the cell-
theory as it is understood and taught at the present day.
I have already pointed out * that the most recent definition
of the cell-theory is, to all intents and purposes, identical
with the broader generalisations of Schwann. Dr. Oscar
Hertwig writes : 2 " Animals and plants, so dissimilar in their
outward appearances, are similar in the essentials of their
anatomical structure, since both are composed of similar
elementary parts which for the most part are only recognis-
able by the microscope. . . . Since the cells, into which
the anatomist resolves vegetable and animal organisms, are
the bearers of the vital processes, they are, as Virchow has
expressed himself, the vital units. Viewed from this stand-
point the whole life process of a composite organism appears
to be nothing else than the extremely complicated result of
the individual life processes of its numerous and variously
functional cells." This is simply a restatement in other
words of two of the fundamental principles of Schwann,
namely (1) that the elementary parts of all tissues are formed

1 G. C. Bourne, "A Criticism of the Cell-theory," Quart. Jour. Micr.
Science, vol. xxxviii., p. 137, 1895.

2 O. Hertwig, Die Zelle utid die Gewebe. Berlin : R. Friedlander
und Sohn, 1893.

ioo SCIENCE PROGRESS.

of cells ; (2) that the cause of nutrition and growth resides
not in the organism but in its separate elementary parts.

The attacks which have recently been directed against
the cell-theory may be resolved into contradictions of these
two fundamental propositions. On the one hand there is
the considerable number of cytologists, whose opinions
may be taken to be summed up in Whitman's essay on
the inadequacy of the cellular theory, who deny the second
proposition, and in so doing implicitly deny the truth of
the first. They would say that the cause of nutrition and
growth does not reside in the cells considered as elementary
parts, but in parts still more elementary, the ultimate vital
units of which the cells themselves are composed. On
the other hand Mr. Adam Sedgwick denies the first pro-
position in toto. He states boldly that the elementary
parts of tissues are not formed of cells, but of a continuous
mass of vacuolated protoplasm containing nuclei.1 These
objections, though they are raised from different stand-
points, are not irreconcilable, but it will be convenient to
deal with them separately. First let us consider the
objections to the cell as an ultimate vital unit.

These objections are of long standing. They were first
brought forward by Briicke 2 in 1861 ;3 not long afterwards

1 Since this was written Mr. Sedgwick has published a further account
of his views, which makes it necessary to modify this statement. See
infra.

2 Ernst Briicke, " Die Elementarorganismen," Sitzungsberichte der K.
Akademie der Wissenschaften, Wien, bd., xliii., p. 381, 1861.

3 Delage points out that the merit of regarding protoplasm as an
organised substance belongs to Dujardin, and not to Brucke. At the
same time he points out the essential difference between Briicke's concept
of organisation and that of Dujardin, greatly to the advantage of the latter :
" La difference entre Dujardin et Brucke est tres simple. Le premier a
devine l'existence de structures que le microscope demontre aujourd'hui ;
tandis qu'en introduisant dans la conception de protoplasma cette notion
acceptee avec enthousiasme, d'organismes tres compliques et invisibles,
Brucke a ouvert la porte aux nombreuses theories speculatives qui cher-
chent a imaginer la structure de ces organismes pour expliquer par elles les
phenomenes de la vie." Delage adopts the expression organisation, saying :
" Le protoplasme n'est pas simplement, comme on l'a cru longtemps, une
substance chimique organique, mais il est organise, c'est-a-dire possede une

THE PRESENT POSITION OF CELL-THEORY. 101

Herbert Spencer followed with his theory of physiological
units. Darwin's theory of pangenesis expressed the same
idea, and more recently Nageli, De Vries, Wiesner, Weis-
mann and others have entered the same or at least similar
objections to the cell-theory. Even Oscar Hertwig, although
he appears in the sentence above quoted to give his
adherence to the view that the cell is a vital unit, abandons
this concept, for all practical purposes, in the latter part of
his book ; for he says, in a most unmistakable manner,
that the cell is an organism composed of ultimate units
which he calls idiosomes.

Each author whose name I have quoted has a somewhat
different account to give of the ultimate constitution of the
cell. But the points on which they disagree are of subor-
dinate importance ; they are all agreed on the main issue,
that the vital activities manifested by the cell are not to be
explained by the visible constitution and structure of the
cell itself, nor by the mere chemical elements of which the
protoplasm of the cell is composed. Each of them avers
that the cell is organised, which means that it is made up of
countless organic units of a lower order, differing among
themselves, and arranged in groups and sub-groups within
the cell in a manner analogous to that in which the cells
themselves are arranged in a composite organism. Since
there is so general an agreement in fundamental principle,
1 am spared the necessity of examining each separate theory
of ultimate vital units in detail ; should anybody wish for a
condensed account of the various theories he will find it in
Weismann's introduction to his work on the Germ Plasm.1

structure d'un ordre plus eleve que la structure atomique des molecules
chimiques des composes organiques non vivants ". No fault can be found
with this definition, but would it not be better to adopt some other term to
express this extra complexity of structure rather than " organisation," which is
inseparably connected with our ideas of the composition of the bodies of
higher animals and plants? For Brucke the organisation of protoplasm
was the same in kind as the organisation of higher animals : for Dujardin
it was something different, and had best be expressed by a different term.
Delage puts the word structure in italics.

1 Still better in Delage's book, referred to further on.

102 SCIENCE PROGRESS.

The point for present consideration is this : Is it neces-
sary for the explanation of vital phenomena to assume
the existence of ultimate vital particles, so minute as
to be invisible with the best microscopical powers
which we possess, each of which is to be considered
as being in posse an independent organism capable of
displaying some of the most characteristic of vital pheno-
mena, viz., assimilation, growth, metabolism, reproduction
by division ?

As it will be necessary to refer frequently to these
assumed vital units, I must call them by some name, and I
shall use Weismann's term biophor, without meaning to
exclude the conceptions of other authors, the pangenes of
De Vries, the plasomes of Wiesner and so forth. I use the
term biophor in the sense of Lebenstrager, the bearer of the
vital properties, without necessarily implying that it pos-
sesses all the particular properties assigned by Weismann
to his biophors.

Whatever the point from which the different authors
have started, they all postulate the existence of minute
biophors on the grounds that the vital phenomena exhibited
by cells, say by an Amoeba, or by the ovum of a Metazoon,
imply the existence of an organisation adequate to the
production of the observed processes. The life processes
are too various and too complicated in their kind to be
explained by the visible constitution of protoplasm, even if
it be allowed, as it generally is allowed, that protoplasm is
not a chemical compound of fixed molecular composition
but a mixture of many chemical substances, each having a
molecular composition of some considerable complexity. I
have already shown that Schwann himself was possessed of
such an idea, which he expressed sufficiently clearly when
he referred to " a peculiar mode of union of the atoms
to form atoms of the second order," but he did not attempt
to follow out the idea, confining himself to the inquiry
into " the arrangement of these conglomerate molecules
when forming either the separate elementary parts of
organisms or the entire organism ". The term consdomer-
ate molecule is in fact synonymous with the term biophor

THE PRESENT POSITION OF CELL-THEORY. 103

in the sense in which I am using it, for the biophor or
ultimate vital unit is held to be an aggregate of chemical
molecules ; the constitution attributed to it is that it is made
up of many different kinds of molecules, just as a molecule
may be composed of several different kinds of atoms. I shall
have to refer aram to the difficulties which still remain if
we accept the hypothesis that a group of different molecules
is able to exhibit the vital functions which are necessarily
attributed to a biophor. Before proceeding to criticism I
must try to give as fairly as I can the grounds for believing
in the existence of biophors. To put the matter as briefly
as possible, the theories of ultimate vital units are the resuh
of attempts to make a mental analysis of living substance
Chemical analysis is impossible, for in the process the
living substance is destroyed as such and becomes dead
substance, possessed of different and much less important
properties. One fact of great importance, however, is
learnt from chemical analysis, and it was appreciated by
Schwann, namely, that, to use his original words, "the
elementary materials of organic nature are not different
from those of the inorganic kingdom " ; hence it has been
inferred, with all reason, that the powers of organic nature
are essentially the same as those of inorganic nature, and
are established by the very existence of matter. It is only
necessary to mention this because there has recently been
a tendency in some quarters to call in the assistance of some
mysterious " vital force " ; a tendency begotten no doubt by
the apparent futility of all attempts to find an explanation
on mechanical and chemical principles of the fundamental
powers of organic nature, assimilation and metabolism.
This, however, need not detain us ; we have to consider
the process of reasoning which, in default of assistance
from chemical analysis, has led so many distinguished
observers and thinkers to analyse the cell into other com-
ponents, and those again into others of a lower grade,
until the biophor, the smallest particle of possible life, is
reached.

The weightiest reason which I have been able to dis-

104 SCIENCE PROGRESS.

cover is given by von Sachs.1 According to this author,
whose views are in agreement with those of Nageli on this
subject, it is necessary for the explanation of certain pheno-
mena exhibited by organic substances that we should assume
the existence of combinations of molecules which form very
large numbers of small particles or micellae as Nageli calls
them. One of the most important of these phenomena is
the imbibition of water. Dry organic substances, such as
gelatine, when placed in water, imbibe it and increase in
volume to a very considerable extent. The increase in
volume produced by the swelling up in water is almost
equal to the volume of water which has been absorbed.
The imbibition of water in such a case is something very
different from the imbibition of water by a porous inorganic
body, such as gypsum, unglazed porcelain, etc. The latter
substances are full of small visible and invisible cavities or
pores, which in the dry state contain air. The water passes
into these cavities or pores according- to the laws of capil-
larity, and in so doing displaces the air, which is forcibly
expelled and can be collected and measured ; there is no
pushing asunder of solid parts, as is shown by the fact that
the porous body is not perceptibly enlarged by the water
which has penetrated into it. But the water penetrating
into gelatine expels no air, it does not enter by capillarity
into spaces previously existent, but forces its way between
the particles of the dry substance, pushing these asunder,
and so causing the considerable increase in volume. The
particles thus pushed asunder are the micellae, and although
they are pushed further apart from one another, they do
not completely lose their connection. Each micella may be
regarded as being surrounded by an envelope of water
when in the moist state ; in the dry state the micellae com-
posing the substance are in mutual contact. This familiar
phenomenon of the swelling of organic substances by the
imbibition of water is contrasted by von Sachs with the
process of solution of a salt. In the latter case the water

XJ. von Sachs, Lectures on the Physiology of Plants, translated by
H. Marshall Ward. Oxford, Clarendon Press, pp. 205 and sq., 1887.

THE PRESENT POSITION OF CELL-THEORY. 105

seizes on the molecules of a crystal and takes them in
between its own molecules ; in the former case the dry
organic body seizes on the molecules of water and forces
them between its own. These reasons are held by von
Sachs and Nageli to be among the weightiest for regarding
protoplasm as an "organised" body, in the sense of being
made up of micellae, and not as being a structureless slime
or fluid.

No doubt they are weighty reasons for regarding or-
ganic substances such as gelatine, starch grains, cell walls,
etc., as being composed of combinations of polyatomic
molecules into groups of a higher order, and there is no
objection to giving these groups a name, such as micellae.
But the admission that such groups exist does not really
bring us much nearer to an explanation of the phenomena
of life. Von Sachs himself points out that even in the
region of pure chemistry it is necessary to assume that
polyatomic molecules are grouped into closer molecular
unions, thus giving rise to chemical properties which did
not belong to the individual molecules.

Gelatine, starch grains and cellulose are not living but
dead substances, and the fact that the behaviour of dead
organic substance finds an explanation on a theory of
micellar structure is but a very small step towards the
explanation of the very different behaviour of living sub-
stance. The micellae may exist in the organic substances
in question, but they are not to be confounded with biophors ;
the very fact that the properties of dead substances may be
attributed to their existence shows that they cannot be con-
sidered as bearers of vital properties.

In point of fact the living substance, which we generalise
under the name of protoplasm, behaves quite differently
in respect of the imbibition of water to the dead substances
which are derived from it. An amoeba or an infusorian,
living in the water, does not imbibe it as a mass of gelatine
would. But when it dies in the same water it immediately
begins to swell up, and eventually bursts and disintegrates.
So that we see that with respect to this very property which
is held to be a reason for assuming a micellar structure of

io6 SCIENCE PROGRESS.

protoplasm, the actual living substance does not exhibit the
property, whilst the same substance when dead does.
Clearly then, the admission that protoplasm has a micellar
structure, that is, that it is composed of minute and invisible
particles consisting of groups of polyatomic molecules, does
not involve the admission that there are ultimate vital units,
biophors, which reside in the cell-like organisms within the
cell-organism. This distinction indeed has already been
made and dwelt upon at some length by Weismann (op.
cit., pp. 41 and 42).

It follows then that whilst we may freely admit that
protoplasm, and also various inert organic substances, are
composed of micellae, and are therefore "organised" in the
sense spoken of by von Sachs, we have still to consider the
evidence for the existence of biophors. At the outset of
this inquiry we meet with a difficulty in that the existence
of biophors is assumed by most authors as a means of ex-
plaining the phenomena of heredity, and this opens up a
wide range of questions into which it is not the purpose of
this essay to enter. But it has well been pointed out by
Wiesner that if minute vital elements occur at all, those
same units which make life possible, and control assimila-
tion and growth, must also be the agents in bringing about
the phenomena of heredity. This view, which commends
itself to everybody, implies that the biophors have only
secondarily acquired historic qualities, and that they are
primarily concerned in the production of the fundamental
processes of life. We may therefore dismiss for the present
purpose the complications introduced by heredity and con-
fine our inquiry to the functions of biophors as bearers of
the essential vital qualities.

It is urged in favour of a theory of biophors that life
must be connected with a material unit of some sort (Weis-
mann) ; that function presupposes structure (Whitman), and
that the structure necessary for the exhibition of such
complicated functions as those of living protoplasm cannot
be of such a simple molecular kind even as the micellar
structure postulated by von Sachs and Niigeli, but must
consist of a definite arrangement, an architecture or organ-

THE PRESENT POSITION OF CELL-THEORY. 107

isation of separate living particles, the aggregate functions
of which produce the vital phenomena. It is further urged
in favour of this view of organisation, that in almost all
cells we are able to recognise structures under the micro-
scope each of which behaves in respect of growth and
multiplication in a manner analogous to that in which the
cell behaves. Not only the nucleus but also the chromatin
bodies, the microsomata of which these are composed, the
centrosomes, the green chromatophores of plant cells, may-
be observed to increase in size, i.e., to grow and to multiply
by division, and it is held that this is proof that the ultimate
particles composing these bodies must assimilate, grow and
divide in a manner similar to that in which cells assimilate,
otow and divide.

This view, whilst receiving a considerable measure of
support from other sources, has been most energetically
supported by Wiesner,1 whose extensive work on the subject
has received the weighty approval of Weismann. Wiesner
refers in detail to the various structures in the form of
granules or corpuscles which may be observed in animal
and vegetable protoplasm, and he attributes to one and all of
them the powersof assimilation and multiplication bydivision.
Nor does he confine himself to the living substance gener-
ally recognised under the name of protoplasm. He labours
at great length to prove that the cell wall, so often con-
sidered as an inert non-living product of living protoplasm,
is not in fact dead, but contains a living substance distin-
guishable under the name dermatoplasm, and ultimately
composed of structural elements of the same fundamental
nature as that of the cytoplasm. These ultimate particles
are the fi/asomes, which form the central point of his theory
of the constitution of living matter. Further than this he
accepts in full the theory of De Vries with regard to vacuoles,
and considers them to be just as much independent organ-
isms as the chromosomes, the centrosomes, the chlorophyll
bodies and other things. This theory of vacuoles, which

1 J. Wiesner, Die Elementar structur und das Wachsthum der Lebendem
Substanz. Wien : Alfred Holder, 1892.

108 SCIENCE PROGRESS.

assumes that they are products of minute bodies called
tonoplasts, is of itself improbable, and is contrary to the
teaching of observations which may readily be made on the
constitution and behaviour of vacuoles in living protoplasm.
It has been shown by Butschli l that the contractile and
other vacuoles of Protozoa continually make their appear-
ance without owing their origin to the division of previously
existing vacuoles. It is not possible to go into details here,
but the reader will find a full discussion of this question in
Butschli's work (p. 230) as also a resume of the various
theories which have from time to time been put forward on
the subject of the granular theory of protoplasm. But even
if peculiar views on the nature of vacuoles be laid aside,
the gist of Wiesner's arguments is not materially weakened.
None of the structures which are observable in protoplasm
are observed to originate neogenetically : they are all, he
says, derived directly by division from pre-existing struc-
tures of similar character. In short, he fully accepts the
aphorism put forward somewhat earlier by Altmann :
" Omne granulum e granulo ". Wiesner does not definitely
say that the various particles observable in protoplasm are
to be severally identified with the ultimate vital units, his
plasomes. Some of them may be individual plasomes, but
the majority of them are, he thinks, aggregates of plasomes,
units of a hioher order which in turn are combined to form
the still higher unit the cell. Thus he presents a scheme
of organisation which, instead of taking the cell as the
lowest structural unit, goes several grades lower ; instead
of the old conception of

organ — tissue — cell,

he represents the scheme of organisation as being

organ — tissue — cell — granules — plasomes.

A detailed criticism of Wiesner's views would occupy a

much larger space than I have at my disposal, and such a

criticism is unnecessary, since all that need be said has

1 O. Butschli, Investigations on Microscopic Foams and Protoplasm.
Authorised translation by E. A. Minchin. London : A. and C. Black,
1894.

THE PRESENT POSITION OF CELL-THEORY. 109

already been set forth by other authors in their criticisms of
similar theories, particularly by Biitschli {loc. cit., p. 195)
and O. Hertwig, both of whom occupy themselves with
Altmann's views, which are to all intents and purposes
identical. Only a few of the most important points need be
touched upon here.

It is certainly a remarkable fact, and confirmed by
abundant experience, that many of the constituent parts of
cells are produced by divisions which recall the divisions of
the cell itself. The nucleus is the most important and the
most familiar constituent of the cell : it is within the experi-
ence of every biologist that nuclei are never observed to
originate neogenetically, but always by division of a pre-
existing nucleus. The chromatin elements of the nucleus may
be shown to be composed of minute particles, the so-called
chromosomes, and these reproduce themselves by division,
and are never observed to originate neogenetically. The
same statement holds good for the centrosomes, for
chlorophyll corpuscles and for various kinds of chroma-
tophores. It is not to be denied that these facts, which
become more and more familiar to the working microscopist,
appear to lend a powerful support to the theory of
biophors ; in a limited sense they may be said to be a proof
of the statement that the cell is an organised body.
Whether, as Wiesner claims to be the case, there are many
other constituents of cells which similarly reproduce their
kind by division, and are never observed to originate
independently, may for the present be left out of considera-
tion. The evidence that amylum grains and granules of
various kinds behave like the centrosomes in this respect, is
as yet too slight, and the observations are too conflicting to
enable us to come to a judgment without entering into a
mass of detail which is not wholly relevant to the question
at issue. But there is at least one criticism which is worthy
of mention, namely, that of Biitschli, who points out {loc. cit.,
p. 200) that among the strongly staining granules of proto-
plasm there are bodies which are not actually constituents
of the protoplasm but are symbiotic micro-organisms.
The existence of such organisms, which have been called

no SCIENCE PROGRESS.

Bacterolds, has been frequently demonstrated in animal
and vegetable cells, and Biitschli points out that granules
similar in appearance to bacteroids occur in the Vorticellinse
and may be observed at certain times to be in a state of
rapid proliferation.

Just before writing these pages I have been shown
preparations exhibiting the numerous bacteria symbiotic
in Pelomyxa, and it is very possible that the rapid
proliferation of bacteroids has been mistaken by various
observers for the reproductive activity of granules forming
an integral part of the cell. It is almost certain that the
mistake has been made in some cases, and until further
investigation has increased our knowledge of the various
micro-organisms which are symbiotic or parasitic in cells, it
is well to be somewhat sceptical of statements regarding
the divisional processes of cell contents. It would seem then
that our present knowledge does not justify our regarding
all the particles of a cell as originating in a similar manner
from the division of pre-existent similar particles, though
we must affirm in the most positive manner that some few
of the constituents of the cell originate in this way only, and
are never produced de novo. The question now to be
considered is this : must we, because these bodies (the
centrosomes, chromosomes, etc.) assimilate, grow and
reproduce themselves by division, regard them as indepen-
dent vital units? A cell exhibits these phenomena and the
cell is regarded as an independent unit in posse, if not
actually in esse ; must we therefore attribute to all bodies
exhibiting the same phenomena the character of indepen-
dent units ? The answer, I believe, is very decidedly no.
Cells would never have been regarded as independent units
if they had merely been observed to assimilate, grow and
divide, whilst retaining their connection with other cells
undergoing the same processes. The quotations which
I have given from Schwann's work show that the
theory that the cell is an independent life unit was not
founded on the fact that it assimilates, grows and divides, —
Schwann indeed overlooked the phenomena of reproduction
by division — but upon the fact that cells are capable of

THE PRESENT POSITION OF CELL-THEORY, in

leading an independent existence. This is so important a
part of the cell-theory that I may again quote in his own
words Schwann's reasons for calling the cell an elementary
unit of life. " Now if we find that some of these elementary
parts not differing from the others are capable of separating
themselves from the organism and pursuing an independent
growth, we may thence conclude that each of the other
elementary parts is already possessed of the power to take
up fresh molecules and grow, and that therefore each
elementary part possesses a power of its own, an indepen-
dent life."

In the case which we are considering the very faculty
which was so powerful a reason for regarding cells as
independent units is wanting. Nobody has ever observed
a nucleus or a centrosome or even a chromatophore to
separate itself from the cell and pursue an independent
existence. And not only is there no recorded case of the
constituent particles of cells separating themselves spon-
taneously from the cell, but experiments which have been
made with the express purpose of determining whether
these particles can live apart from the cell to which they
belong have in every case given a negative result. Even
the nucleus, highly complicated as it is, and itself composed
of smaller particles which may easily be demonstrated,
perishes when removed from the cell body. The chroma-
tophores similarly perish, and so no doubt would the
centrosomes if it were possible to isolate such very minute
particles. Many instances might be cited in proof of this,
but it is scarcely necessary to bring forward the details ;
the reader can obtain them by reference to the works of
Nussbaum,1 A. Gruber and Verworn.2

It is of some interest in this connection to contrast the
process of reproduction in unicellular and multicellular or-
ganisms. In the latter reproduction is effected by the
separation of a single unit, a cell, from the aggregate, and

1 M. Nussbaum, Biol. Centralblatt, vol. iv.

2 Max Verworn, " Die physiologische Bedeutung des Zellkerns,"
Pfliiger s Archiv, vol. li., 1892.

ii2 SCIENCE PROGRESS.

the unit so separated has from the time of its separation an
independent individuality and eventually reproduces the
aggregate. The fact that the union of two cells is commonly
necessary for the maintenance of life and the exhibition of
the powers of development, need not be urged as an objec-
tion to this simple statement of the case, for the facts of
parthenogenesis show that the union of two cells is not an
essential feature. Now if we adopt Wiesner's scheme, and
imagine that organisation does not stop at the cell, but that
beyond this there are granules, and beyond these again
plasomes, and that the plasomes stand in the same relation
to the cell that the cell stands to the multicellular organism ;
we should expect to find that in the reproduction of
monocytial organisms the plasome plays a part anal-
ogous to that played by the cell in the reproductive
processes of polycytial organisms. But we find nothing
of the kind. The monocytial organism reproduces itself in
just the same way as the polycytial, by the separation of a
cell, complete in all its parts. There is no such thing
known, even in cases where a flagellate or a radiolarian
breaks up into innumerable particles or spores of extreme
minuteness, as the separation of any one individual con-
stituent of a cell possessed of the power of leading an in-
dependent existence and in time of reproducing all the other
constituents. Every spore, however minute, has its portion of
the cytoplasm and its share of nuclear matter. If there are
any other constituents, it probably has its share of these
also, but one cannot speak with certainty on this point, for
positive evidence is wofully deficient. At any rate Wiesner,
holding fast to his theory that nothing, not even an amylum
or an aleurone grain, is produced neogenetically, is at great
pains to prove that in cellular reproduction all the parts
of the parent are transferred to the offspring. Assuming
that this is so, and remembering that there is abundant
evidence that nuclear matter and cytoplasm are always
transferred, it is evident that the relation in which the
plasomes or biophors, regarded as ultimate vital units,
stand to the cell, is not at all the same as the relation in
which the cell, regarded as an ultimate unit, stands to the

THE PRESENT POSITION OF CELL-THEORY. 113

polycytial organism. Biitschli, in a short but very weighty
sentence,1 brings forward the same argument that I have
just used in opposition to Altmann's theory of the part
played by granules in the vital processes of protoplasm. In
my judgment the argument as far as it goes is a sound
one, but I am aware that it does not altogether refute the
theory of biophors, but only that part of it which states that
as cells are to polycytial aggregates so are biophors to cells.
This refutation, however, seems to me to be a considerable
gain. For it enables us to apprehend that the structure or
constitution of the cell, whatever it may be, is not to be ex-
pressed in the same terms as the structure of the higher
organisms.

It may be objected that nobody does express the
structure of the cell in such terms, but the objection does
not hold good. It is true that most authors are more
guarded in their expressions than Wiesner, and evade the
responsibility of declaring that the biophor is to the cell
as the cell is to the polycytial organism, by means of re-
servations, couched for the most part in terms so ambiguous
and even transcendental that the whole issue is involved in
an obscurity from which it seems hopeless to try to escape.
But these expedients are really of little use. The fact re-
mains that in every case the fundamental idea is the same,
that the phenomena exhibited by isolated cells having an
independent individual existence are of essentially the same
kind as the phenomena exhibited bypolycytial organisms and
must be explained on the same grounds.

If it be not so, what is the meaning of the argument
which was first put forward in definite shape by Brlicke,
and has been repeated by every author who attacks the
question in the same manner that he did, that the com-

1 " So long as the individual constituents of the cell are not seen to
persist when isolated, nor are distinct living phenomena observed in them,
it is very dangerous to speak of their life as something which they possess
in themselves. They are so far living, as long as the opposite is not proved,
in that they are parts of living organism, so that the granula may be
living in the same way as the nucleus, even though they no longer betray
any sign of life after isolation" (Joe. eit., p. 199).

8

ii4 SCIENCE PROGRESS.

plexity of the phenomena exhibited by individual cells, say
by an amceba, is so great, the functions observed are so
many and so various in their kind that they can only be
explained by the assumption that protoplasm is an organised
body ? Taking the words of O. Hertwig as a fair ex-
pression of current opinions on the life processes of a poly-
cytial organism, " that the aggregate life processes of a com-
posite organism appear to be nothing more than the ex-
ceedingly complicated result of the individual life processes
of its numerous and variously functional cells," it is evident
that to the minds of Briicke and his successors the aggre-
gate life processes of the corpuscle of protoplasm called a
cell are nothing more than the highly complicated result of
the individual life processes of its numerous and variously
functional biophors. If they do not mean this, I am quite
at a loss to know what they do mean, or to understand the
relevancy of the so-called axiom laid down by Whitman,
that "function presupposes structure," or the meaning of
the statement expressed so often and with such obvious
satisfaction, that " the cell is an organism ". These sen-
tences, so terse and so epigrammatic, exercise a peculiar
fascination over most minds. To understand their exact
applicability to the question at issue they must be carefully
examined. Function presupposes structure. To the bio-
logist who makes a rapid mental survey of his experiences,
this appears to be a generalisation of universal truth.
Physiology, which draws its inferences almost exclusively
from the study of the higher animals, tells us that ultimately
every function of the composite organism is to be referred
to a particular group of cells, and that cells differ in kind
according to the different functions which they exhibit. So
much is this truth forced upon us that if conceivably a new
function were to make its appearance, we should immediately
search for the cell groups appropriate to the performance of
that function. So far so good, but before proceeding further
we must take note that the statement that function pre-
supposes structure is a generalisation founded on experience.
It is not an axiom as Whitman calls it, for an axiom is a
proposition which is self-evident, and this assuredly is not.

THE PRESENT POSITION OF CELL-THEORY. 115

The next step is to transfer this generalisation, founded on
experience, into a new region, to the functions of cells. In
order to do this we should possess the same experiences
with regard to the functions of cells which we possess
with regard to the functions of composite organisms. But
these experiences are entirely wanting. We observe that
protoplasm exhibits functions, that it assimilates, that it is
irritable, that it is contractile, that it is reproductive, and so
forth ; but who has been able to demonstrate or even to
suggest with any plausibility that there are structures
specially devoted to assimilation, to contractility, to irrit-
ability, and to reproduction in protoplasm? It is evident
that the absence of any such experiences has been felt by
many observers, who have accordingly studied protoplasm
with a view to finding the required structures, and some
are inclined to say that the nucleus or perhaps the centro-
some is reproductive, the amylum and aleurone bodies are
assimilative and so forth. But there are protozoa endowed
with active functions which have no centralised nucleus ;
the presence of centrosomes has yet to be demonstrated in
protozoa in general, and there are forms in which, as
Biitschli well points out, the protoplasm is homogeneous,
e.g., in the pseudopodia Gromia dujardini} The reader
should refer to Biitschli's work for a discussion of the sub-
ject of hyaline protoplasm (loc. cit., p. 262). The fact that
it exists is of the highest importance, for it shows that there
is living substance exhibiting the usual vital phenomena of
assimilation, contractility, etc., which, nevertheless, defies
all attempts to recognise an organisation which in the light
of previous experience would seem adequate to the effects
produced, and it shows also that the centrosomes, the
amylum grains, and their analogues, and the whole category
of granules are secondary phenomena, which may be

1 Not only are there no granules in homogeneous protoplasm, but the
alveolar structure of it is unrecognisable. It is easily shown, however, that
the homogeneous substance is produced from alveolar protoplasm and is
capable of reconversion into it. The physical explanation of the dis-
appearance of the alveolar structure is given by Biitschli on p. 264 of the
English translation of his work.

n6 SCIENCE PROGRESS.

altogether absent and yet the life processes go on un-
changed.

It must be confessed then, that the experiences which
so amply justified our generalisation when applied to com-
posite organisms are altogether lacking when we seek for
a justification for applying it to the simplest unicellular
organisms. Moreover I have just shown that in one im-
portant particular at least, we do not merely lack these
experiences, but that we have experiences of an entirely
different kind. In face of this is it not obvious that the
captivating generalisation must be abandoned altogether in
the region which we are now discussing ? For it is founded
on experience, and where experience fails or is contradictory
the generalisation fails also.

After what has already been said it is unnecessary for
me to enter into a detailed examination of the other state-
ment which is considered to mark a great advance in bio-
logical thought, that "the cell is an organism". It is
sufficient to say that if this proposition means anything at
all, it means that the cell has an organisation which is
similar in kind to that of a composite organism of which a
cell is a part. If I am told that it does not mean this, but
something else, then I ask, firstly, what does it mean ? And,
secondly, if it does not mean this, what necessity is there for
assuming that the protoplasm of the cell is built up of bio-
phors, the biophor being the elementary living constituent,
assimilating, growing and dividing, taking up definite posi-
tions in the cell, combining with others like or unlike itself to
form higher aggregates, and so impressing a fixed archi-
tecture on the cell of which it is a component ? Why, in
short, if the statement does not mean that the organisation
of the cell is the same in kind as the organisation of a
composite animal, why then does everybody who believes
that the cell is an organism ascribe to it an organisation
which is the same in kind as that of the higher animals ?

The fact is, and it is patent to everybody, that most
authors do conceive of the cell-organisation as being the
same in kind as the organisation of higher animals. They
either have the courage of their opinions, like Wiesner,

THE PRESENT POSITION OF CELL-THEORY. 117

and say so in so many words, or they tacitly admit it by
their description of what they conceive cell-organisation to
be. They are dominated by the cell-theory. Mr. Adam
Sedgwick has recently said that the cell-theory is an incubus
which perverts the minds of biologists, whose minds are so
saturated with conceptions borrowed from the cell-theory
that they are unable to see anything else. I have else-
where found fault with this statement, but when the theories
of cell-organisation are considered, I must freely confess
that he has right on his side. Not only does the zoologist
believe "that the cell is the unit of structure, and that it
forms the basis of organisation in the metazoa," but he also
believes that some correlative of the cell forms the basis
of all organisation whatsoever. His eyes are " blinded to
the most patent facts" by ideas derived from the cell-theory,
and it is not too much to say that the theory does " obstruct
the way of real progress in the knowledge of structure ".
Whether consciously or unconsciously the believer in bio-
phors starts with ideas derived from the cell-theory, he
tacitly assumes the universal applicability of the proposition
that function presupposes structure, and he seeks to explain
the functions of protoplasm by attributing to it an organisa-
tion which in all essential characters is the equivalent of
the organisation of the metazoa. Since I have just shown
that there is no justification for transferring a generalisation
based upon experience to a region in which experience is
either wholly wanting or, if present, of a different kind, it is
hardly necessary for me to elaborate and show that it is
equally unjustifiable to attribute to the unknown a plan of
organisation identical in kind with the plan which we have
learnt by experience to recognise as the attribute of the
known.

Some time ago I pointed out that there was a fallacy in
the word organism.1 Whitman has ridiculed the statement,
yet the more I reflect upon it the more I am convinced
that the fallacy exists, and that it is in the highest degree
mischievous and misleading. By an organism we mean

1 G. C. Bourne, " Epigenesis and Evolution," this journal, vol i., 1894.

n8 SCIENCE PROGRESS.

either an independent living thing, in which case the term
is loose but applicable to every animal in the monocytial
stage, or we mean a thing possessing organisation, and by
organisation we mean a certain structural plan, the idea of
which is a generalisation from our experience of animal and
vegetable structure in general. That this is historically
and in fact the connotation of the term organisation is in-
dubitable.1 When we use the term organisation we
either use it in this connotation or in some other. If we
use it in the same connotation with respect to protoplasmic
structure, we are consistent, but, as I have shown, we are
applying ideas derived from one set of phenomena to
another set of phenomena to which they are not appropriate.
But if we use it with another connotation, then we expose
ourselves at once to the risk of the well-known fallacy which
is inseparable from the use of the same term with different
connotations. If the two connotations are clearly defined
and generally understood, the fallacy may be avoided,
though the inconvenience remains ; but if the one connota-
tion is clear and definite whilst the other is vague and
ambiguous in the highest degree, no amount of circum-
spection will prevent our falling into the fallacy almost at
the first opportunity. This is exactly the case with the term
organisation. In the one sense we know its connotation
exactly, and when authors use it in that sense they have,
in the course of their arguments, to adhere strictly to the
technical sense of the word. Most of them do this, for
they are aware of the absurdities and inconsistencies into
which they would fall if they did otherwise. But what
of those who use the term with another connotation ? They
assure us that it does not denote a plan of structure like in
kind to that of the metazoa : what then does it denote ?
Something so vague, so unreal and unsubstantial that we

1 Thus in Worcester's Dictionary of the English Language, 1881 : —
Organisation. The condition of an organised body or the totality of

parts which constitute and the laws which regulate an organised body.

Organised. Formed with organs : composed of several individual parts

or organs, each of which has its proper function and conduces to the

existence of the entire system.

THE PRESENT POSITION OF CELL-THEORY. 119

are even at a loss to know to what to apply it ; its connota-
tion has never even been attempted. The futility of using a
term without connotation and with the most vague denotation
is so well illustrated by the following passage from Whit-
man that I cannot refrain from introducing it here : " When
we speak of the organisation of the germ as cut directly
from a pre-existing parental organisation of the same kind
we are not thinking of the definitive organisation which
belongs to the fully formed organism, but of that primary
organisation which belongs to the protoplasm itself". This
raises our expectations, we are going to hear something of
the primary organisation which belongs to protoplasm itself.
Whitman continues: "We are so accustomed to connect
the idea of organisation with the anatomical organs of the
adult that we are apt to forget that there is a primary
organisation which underlies every anatomical organ. The
germ has this primary organisation ; it is therefore an
organism, and as such may dominate its own development."
From which weighty and sententious passage we gather
that the germ is an organism because it has a primary
organisation which is not the definitive organisation which
belongs to the fully formed organism, but a primary organ-
isation which belongs to protoplasm itself. What on earth,
we may well ask, is this primary organisation ? The
answer is given on the same page. It is "that original
constitution of the germ which pre-determines its type of
development and the form which ultimately distinguishes it
from other species developing under like external conditions".
The terms "original constitution" and "primary organisa-
tion " are merely synonyms. So we learn that the primary
organisation so important to those who have more thought-
fully scanned the gap between the cell and the physical
molecule, is the primary organisation of the germ, which
pre-determines its type of development, etc. I hope that
others are satisfied by this most remarkable piece of
scientific exposition. For myself I must humbly confess
that I am none the wiser for it, any more than I should be
if I asked what was a Megalosaurus and I was told : "A
Megalosaurus, why you know it is a big lizard, it is — a — a

120 SCIENCE PROGRESS.

Megalosaurus in fact ". Nor is confusion less when I am
told in one sentence that the organisation of the germ cut
directly from pre-existing parental organisation of the same
kind is not the definitive organisation which belongs to the
fully formed organism, but is that primary organisation
which belongs to protoplasm itself, and I read in the
sentence immediately preceding that " the essential thing is
not simply continuity of germ substance of the same
chemico-physical constitution, but actual identity of germ-
organisation with stirp-organisation ". The organisation of
the germ is identical with the organisation of the stirp, and
yet the organisation of the germ is not that of the fully
formed organism, but is a primary organisation which
belongs to protoplasm itself. What does it all mean ? It is
different and yet it is identical, and it is organisation, organisa-
tion, toujours organisation. I beg Dr. Whitman, for pity's
sake, to descend from his altitude, scarcely dreamed of in the
philosophy of Harvey and Wolff, and to condescend to
inform a poor bewildered mortal, who confesses to a pre-
judice in favour of things which he can understand, what
this wonderful primary organisation is.

Seriously speaking I believe that organisation either
means a plan of structure of the same type as the structure
of higher animals and plants, and capable of being described
in intelligible terms as it has been by Weismann, Wiesner
and others, or it means nothing at all ; it is a mere phrase
which seeks to cover but does not conceal our ignorance.

G. C. Bourne.
( To be continued. )

SOLID SOLUTIONS.

IF we define solutions as homogeneous mixtures of sub-
stances in variable proportions, we are at once obliged
to admit the existence of solid solutions, for there are many
mixed solids which fulfil the requirements of this definition.
Common potash alum, for example, can crystallise together
with ammonia alum, and form mixed crystals which are
perfectly homogeneous and of the same composition through
out, although the proportions of the two constituents may
be varied at will by proper selection of the aqueous solution
from which the crystals separate.

We are inclined, however, to look in solutions for some-
thing more than mere homogeneity and uniformity of com-
position, and perhaps one of the most obvious characters of
a liquid solution is this, that should it at first be of different
composition in different parts of its mass, there is always
present the tendency of the dissolved body to attain a uni-
form distribution throughout the solvent. The process of
equalisation of the composition, or diffusion, occurs in all
solutions which are more concentrated in one part than in
another, the dissolved substance moving from the place of
greater to the place of less concentration. Diffusion in
solution goes forward very slowly if the liquid is protected
from mechanical disturbance and sudden change of tem-
perature, months being requisite for the attainment of uni-
form concentration if a comparatively short column of pure
solvent is placed above a denser layer of strong solution
contained in the bottom of a cylinder. If diffusion takes
place in solids we might expect it to proceed even more
slowly.

A class of substances which form in some sort a connect-
ing link between liquids and solids, and are specially suited
to the study of diffusion phenomena, is to be found in jellies.
Graham, to whom we owe our first exact knowledge of
diffusion in liquids, prepared a stiff jelly containing common
salt in solution in one part, and compared the rate at which

122 SCIENCE PROGRESS.

the salt diffused in it with the rate at which salt dif-
fused in pure water. He found that the diffusion in the
jelly took place almost, if not quite, as fast as in water
itself. The composition of the jelly was 2 per cent, gelose
and 98 per cent, water, so that, as far as actual substance
was concerned, the salt had to meet practically the resistance
of water alone in both cases, and the experiment showed
that the mere change in apparent condition of the whole
mass had little or no influence on the rate of diffusion.
Subsequent experiments have served to confirm Graham's
results.

When we pass to solids proper we find that instances
are not wanting of what is apparently diffusion within them.
Van't Hoff in his fundamental paper on solid solutions gives
numerous examples. In the preparation of steel by the cem-
entation process bars of wrought iron are packed in charcoal
and subjected to a red heat for several days. The charcoal
gradually penetrates the iron and converts it into steel. It
matters little for our purpose what the particular form is that
the carbon assumes during its passage through the iron — in
some fashion or other it reaches the centre of the dense bar.
The distribution of the carbon, too, if the operation is inter-
rupted before uniformity has been attained, is precisely what
would be expected if the phenomenon were one of real diffu-
sion ; and the influence of time is the same in both processes.
Not only has carbon been observed to pass through iron,
but it has even been proved to travel slowly through por-
celain, when porcelain crucibles have been heated in a bed of
graphite.

When a metal such as copper is deposited galvanically
on another metal, it penetrates beyond the surface of the
latter into its substance, and zinc objects which have been
lightly coppered are, even when protected by a coating of
varnish, occasionally observed to become white again
owing to the gradual mixing of the two metals near the
surface.

Professor Spring, of Liege, who has devoted special
attention to the chemical behaviour of solids under high
pressure, has supplied some interesting instances of pheno-

SOLID SOLUTIONS. 123

mena which can only be explained by the assumption of
solid solutions. When equivalent proportions of barium
sulphate and sodium carbonate are finely powdered,
intimately mixed, and subjected to a very high pressure, a
double decomposition takes place with formation of barium
carbonate and sodium sulphate. The decomposition, how-
ever, is not complete, only 20 per cent, of the original
substances being transformed. If, on the other hand, we
start with a mixture of barium carbonate and sodium
sulphate and compress it, we find that the reverse trans-
formation now occurs, barium sulphate and sodium carbonate
being formed, and that to the extent of So per cent, of the
original substances present. Here we are evidently dealing
with a state of equilibrium between the four substances
above mentioned, which can only exist together permanently
under pressure in certain definite proportions. If these
proportions are departed from, the system so transforms
itself that the requisite state for equilibrium is attained.
Now this of itself points to the substances existing here in
a state analogous to that of bodies in liquid solution, for we
know that in general definite proportions are necessary in
solutions for stable equilibrium to exist. In the case of
solids the general rule is that when they are in equilibrium
under given conditions in one proportion, they are in
equilibrium under the same conditions in every other pro-
portion. The behaviour, then, of these solids under pressure
is analogous to the behaviour of substances in solution, and
different from the ordinary behaviour of solids. The con-
tinuance of the pressure is not essential to the establishment
of such a definite solid equilibrium, for Spring has shown
that by relieving the pressure after 73 per cent, of a
system of barium carbonate and sodium sulphate had been
transformed, the process continued, though less rapidly,
and after a week had reached the proportion of 80 per cent,
necessary for equilibrium. Here diffusion must have played
a part, for no matter how finely divided the reacting sub-
stances originally were, their surface of contact (where alone
the mutual decomposition could take place if there were no
diffusion) must have been comparatively small.

124 SCIENCE PROGRESS.

It is well known that some metals have the property of
allowing certain gases to pass through them under favourable
conditions, the most thoroughly investigated instance of
this kind being the permeability of the metal palladium to
gaseous hydrogen at moderately high temperatures. At
about 300° C. hydrogen can pass quite freely through a
palladium septum, and it is difficult to conceive the nature
of this phenomenon without admitting the existence of
diffusion in the solid. Whether the hydrogen is dissolved
in the palladium or forms a compound with it, as has been
asserted, is of little consequence, for in the latter case the
compound superficially produced must have possessed the
power to penetrate the remaining metal, or to allow of the
passage of hydrogen through itself.

Connected with the process of diffusion in solution we
have the phenomena of the conduction of electricity in
solutions, or electrolysis. Here the electric current is
carried by material particles, and the resistance that these
experience in their passage through the solution is of the
same nature as the resistance offered to diffusion. Helm-
holtz, in his Faraday lecture, drew attention to the fact that
glass behaves as an electrolyte towards an electric current,
i.e., that the current in passing through the glass is as-
sociated with two currents of particles moving in opposite
directions. The particles travelling towards the negative
pole of the battery have since been proved to move faster
than those moving towards the positive pole. Lehmann
also has shown that when two silver electrodes are immersed
in fused iodide of silver, which is afterwards allowed to
solidify, and a current of electricity is passed through the
solid iodide, one of the electrodes increases in weight at the
expense of the other, and that the phenomenon can be
reversed by reversing the current.

These examples will suffice to indicate that we are not
without data to establish an analogy between the behaviour
of certain solids and the behaviour of ordinary liquid solu-
tions. Since the appearance of van't Hoff's original paper
on the subject a considerable number of researches have
been published more or less directly bearing on the question,

SOLID SOLUTIONS. 125

but the results achieved have on the whole been small, owing
chiefly to the experimental difficulties encountered.

An important application of the idea of solid solutions
was made by van't Hoff in explaining the abnormalities
that are sometimes met with in the determination of mole-
cular weights by the lowering of the freezing-point in solu-
tions. It had been proved theoretically that the freezing-
point of a given solvent should be depressed to a certain
value (calculable from the freezing-point and the latent
heat of fusion of the solvent) when the solution was of
normal concentration, i.e., contained one gram-molecule
of dissolved substance per litre. The nature of the dis-
solved substance should be without influence on this value.
Now, whilst it was ascertained experimentally that this
theoretical relation was in the vast majority of cases ac-
curately fulfilled, yet there remained certain combinations
of dissolved substance and solvent which gave values of the
depression constant altogether at variance with the cal-
culated value. Thus, metacresol dissolved in phenol gave
a depression of 48 instead of 74, and thiophene dissolved in
benzene a depression of 34 instead of 53. Van't Hoff's
explanation of these and similar abnormally low values of
the depression was that the freezing-point observed was not
in the strict sense the freezing-point which had been assumed
in the theoretical reasoning. The true freezing-point of a
solution is the temperature at which the liquid is in equi-
librium with the solid solvent. The freezing-point of an
aqueous salt solution, for example, is the temperature at
which it can exist in contact with pure ice without the ice
melting or without fresh ice being deposited from the solu-
tion. Now, in the exceptional cases above alluded to it is
known that the solid and the solvent have a tendency to
crystallise together, i.e., to form mixed crystals, so that the
substance that separates out is not the pure solvent but
rather a solid solution. The temperature at which such a
solid solution would be in equilibrium with the liquid solu-
tion might not by any means be the freezing-point of the
solution as above defined. The apparent observed freezing-
point of the solution, therefore, would not in general coincide

126 SCIENCE PROGRESS.

with the calculated depression, and van't Hoff from theo-
retical considerations showed how the divergence could be
estimated from a knowledge of the composition of the solid
which actually separated out from the solution on cooling.
That the abnormal values for the points of solidification
depend on the separation of the dissolved substance along
with the solvent has now been experimentally verified in a
considerable number of cases. Heycock and Neville found
that for the case of solutions of antimony in molten tin, the
freezing-point of the tin was raised instead of lowered by
the presence of the second metal. Kiister has shown that
this and similar instances are susceptible of a very simple
explanation. The two metals separate out together in very
nearly the same proportion as that in which they remain
behind in the liquid, so that the solution solidifies as a
whole. In such circumstances the point of solidification of
the liquid can be calculated by the simple mixing formula.
If the melting-point of each pure substance is multiplied by
the proportion in which it exists in the mixture, the sum of
the two numbers thus obtained will give the point of solidi-
fication of the solution. As antimony melts 200 degrees
higher than tin, the admixture of the former in however
small proportion will, since the mixture freezes as a whole,
raise the point of solidification instead of lowering it, as
would be the case if pure solid tin separated from the liquid
on cooling.

Not only do solutions exhibit a lower freezing-point than
that of the pure solvent, but they also exhibit a lower
vapour tension. The pressure of aqueous vapour over
salts containing water of crystallisation may in many cases
be measured with accuracy, and there it is found that the
isomorphous admixture of another salt lowers the vapour
pressure of water which is in equilibrium with the solid.
Thus the vapour tension of a mixed crystal of ordinary alum
with iron alum is less than the vapour tension of either of
its components. In this respect then the mixed crystal
behaves as a solid solution. Again, the solubility of a sub-
stance is diminished when it itself acts as a solvent for
another substance insoluble in the original solvent. Of the

SOLID SOLUTIONS. 127

three liquids, ether, water, and benzene, ether and water are
partially miscible, benzene and water are immiscible, and
ether and benzene miscible in all proportions. Suppose we
take water as the original solvent — then on shaking it up
with ether we find that the latter dissolves to a certain
definite extent in it, i.e., possesses a certain solubility
in water. If now we previously dissolve benzene in the
ether which we shake up with the water, we find that the
water will now take up less ether than before. The solu-
bility of ether in water is thus diminished when benzene is
dissolved in it — and this behaviour is characteristic of all
such combinations of substances.

A case of this kind where two solids play the part of the
ether and benzene in the previous instance has been
thoroughly studied by F. W. Klister. The solid hydrocarbon
naphthalene is, like the hydrocarbon benzene, insoluble in
water ; /3-naphthol, on the other hand, is, like ether,
sufficiently soluble in water to permit of accurate estimation.
But naphthalene and /3-naphthol can crystallise together in
any proportion so as to form a complete series of isomor-
phous mixtures, the melting-points of which vary according
to the rule given above for mixtures of antimony and tin.
A comparison of the amount of /3-naphthol dissolved by a
given quantity of water from such mixtures led to some-
what unexpected results. Instead of the addition of a
small quantity of naphthalene to /3-naphthol lowering the
solubility of the latter in water, it was found that mixtures
containing as much as 30 per cent, of naphthalene had
precisely the same solubility as /3-naphthol itself. As more
naphthalene was added the solubility increased slightly,
afterwards to diminish continuously to zero as the mixture
was made to contain more and more naphthalene. The
explanation of this behaviour suggested by Klister is that
naphthalene and /3-naphthol are capable of forming a chemi-
cal compound consisting of one molecule of each substance,
this compound being decomposable by water, an assumption
by no means improbable, as many similar cases have been
observed. If we allow further that the solubility of the
compound is greater than the solubility of /3-naphthol, the

128 SCIENCE PROGRESS.

results are satisfactorily accounted for. The diminution
of solubility when much naphthalene is present is the
normal depression of the solubility of the compound by
the addition of excess of naphthalene. The solubility
greater than that of pure naphthol is the solubility of the
compound naphtholnaphthalene. The constant solubility
(equal to that of /3-naphthol) observed when there is little
naphthalene in the mixture is the solubility of /3-naphthol,
for the naphthalene in the mixture is in the form of the
compound naphtholnaphthalene, which is decomposed at
the surface by water into naphthalene and /3-naphthol,
which exist now alongside of each other and not in the
intimate union of a crystalline isomorphous mixture.

In connection with the results of these experiments
Klister is inclined to make a distinction between crystalline
isomorphous mixtures and solid solutions proper, because in
the former there is practically no diffusion owing to what
may be termed the rigidity of the crystalline structure.
He admits, however, that no absolutely sharp line can be
drawn, as there are various intermediate degrees in which
diffusion may take place. A reference to the examples of
diffusion in solids previously cited in this paper will show
that they all occur in amorphous bodies without any regular
structure.

A point of considerable interest in the theory of solid
solutions is that it affords us the possibility of determining
molecular weights of the dissolved substances, and since in
isomorphous mixtures we usually attribute similarity of
molecular structure to the two components, we can also in
this case form an estimate of the molecular weight of the
solid solvent. From his experiments on the amount of /3-
naphthol dissolved by water from mixtures of that substance
with naphthalene, Kiister was able to calculate with a high
degree of probability the molecular weight of each of these
substances in the solid state. In the first place he found
that with mixtures containing excess of naphthalene the
ratio of the square root of the concentration of /3-naphthol
in the solid mixture to the concentration in the aqueous
solution saturated by that mixture was very nearly constant,

SOLID SOLUTIONS. 129

varying but little with the actual composition of the mixtures
taken. The general theory of solutions asserts that when a
substance(here /3-naphthol) is divided between two immiscible
solvents (here water and naphthalene, or naphtholnaph-
thalene) it will be distributed in a constant ratio between
the two solvents, no matter what amount of it be taken,
provided only the molecular weight of the substance is the
same in both solvents. In the case investigated this does
not hold — the ratio of the concentrations in the two solvents
is not constant ; and the molecular weight of /3-
naphthol dissolved in water is therefore different from the
molecular weight of /3-naphthol " dissolved " in naphthalene.
The theory further asserts that when, as in the present
instance, the concentration in one of the solvents is pro-
portional to the square root of the concentration in the
other solvent, the molecule in the second solvent must be
twice as great as the molecule in the first. We know that
/3-naphthol dissolved in water has the normal molecular
weight corresponding to the formula CIOHsO ; in naphthalene
solution it has consequently the molecular weight corre-
sponding to the formula (CIOH80)2.

The theory of solutions likewise enables us to calculate
the molecular weight of the naphthalene in the above
experiments from the diminution of the solubility of the
/3-naphthol in water as it dissolves more and more naph-
thalene. In the case before us the question is slightly com-
plicated by the existence of naphtholnaphthalene molecules,
but Kiister was able to arrive at the result that naphthalene
must have double the molecular weight in the state of solid
solution that it has in the state of vapour, viz., (CIOH8)2.

Another well-investigated case of solid solutions is that
offered by the absorption of hydrogen by palladium.
T roost and Hautefeuille, in order to obtain information as to
the state in which the hydrogen existed within the metal,
made an extensive series of observations of the pressure of
hydrogen in equilibrium with palladium containing different
amounts of hydrogen. They found that with compositions
of the solid up to one atom of hydrogen to two atoms of
palladium the pressure of hydrogen remained constant

9

i3o SCIENCE PROGRESS.

at ioo° C, after which it increased rapidly as the pro-
portion of hydrogen in the solid increased. The analogy
between this case and the case of the solubility of mixtures
of /3-naphthol and naphthalene in water is at once apparent.
In both instances we have constancy of pressure (gas-
tension) and solubility (solution-tension) within a certain
range of composition, and then rapid variation with further
change of composition. The conclusions arrived at in both
instances are also similar. The constant solubility was
attributed by Klister to the formation of a compound
naphtholnaphthalene — the constant tension was attributed
by Troost and Hautefeuille to the formation of a compound
Pd2H, in which any excess of hydrogen was then absorbed.
Quite recently, however, grave doubts have been thrown
on the existence of this compound. A very careful repetition
and extension of Troost and Hautefeuille's experiments by C.
Hoitsema has proved that the constancy of tension observed
by these investigators was not absolute but only approxi-
mate, and that under slightly varying conditions the
apparent constancy disappeared altogether. It would
seem, therefore, that no compound of palladium and hydro-
gen is formed when the gas is absorbed by the solid, the
state of the hydrogen being rather one of simple solution
in the palladium. A comparison of the concentrations of
the hydrogen above the palladium and of the hydrogen in
the palladium indicates that at very low pressures the
hydrogen in the metal exists as molecules only half as great
as those of the gas, i.e., as molecules consisting of only one
atom. At higher pressures the concentration of the free
gas and that in the palladium stand in a nearly constant
ratio, from which it is to be inferred that the molecule of
hydrogen in the metal, as well as the molecule of gaseous
hydrogen, is represented by the formula H2.

A problem which has long interested chemists is the
determination of the nature of the process involved in dyeing.
Some contended that the process was one of chemical union of
the dye with the substance of the fibre, others that it was
merely one of mechanical absorption. In 1890, however,
O. N. Witt propounded a new theory which, on account of

SOLID SOLUTIONS. 131

its plausibility, met with a ready acceptance in many
quarters.

According to Witt the state of the dye-stuff in the fibre
is one of solid solution, and many analogies were advanced
in support of this assertion. For example, dyed materials
show the colour, not of the solid dye-stuff, but of the dye-
stuff in solution, when there is a difference of colour between
the two states. Solid fuchsine is green, its aqueous solutions
are red, and so also are materials dyed with it. The dye-
stuff rhodamine in the solid state exhibits no fluorescence, in
solution it does, and silk dyed with rhodamine is fluorescent
likewise. The theory of Witt thus appeared very promising
as an explanation of the phenomena of dyeing, but a closer
investigation has shown that it cannot be accepted uncondi-
tionally, although some modification of it may be found to
satisfy the experimental requirements. It has been proved
in a considerable number of instances now investigated
that the concentrations of the dye in the dye-bath and
in the fibre do not stand to each other in a relation
of simple proportionality, but the concentration in the bath
is roughly proportional to a power (usually 3 to 5) of the
concentration in the fibre. Now on the theory of solid
solutions this indicates that the molecule of the dye in the
water is three to five times as great as the molecule of the
dye in the silk ; but this cannot be the case, for the mole-
cule of the dye-stuff in aqueous solution can be shown by
other means to be the simplest possible. The numbers
rather indicate analogy to the process known as absorption
from solution. Substances like animal charcoal and
platinum black have the property of condensing gases in
the extensive surface they present. Similarly they can
abstract certain substances from solution, as may be seen in
the employment of animal charcoal for the decoloration of
solutions. The relation between the concentration in the
solution and that in the charcoal proves to be of the same
kind as is met with in dyeing, so that we are led to suspect
a similarity in the nature of the two processes. The so-
called "iodide of starch," the blue compound formed when
starch and iodine solution are brought into contact, would

i32 SCIENCE PROGRESS.

appear to be a substance of the same nature as a dyed fibre
and as charcoal saturated with an acid from solution, for the
concentrations of the iodine in the aqueous solution and in
the starch obey approximately the same law as in the other
instances.

We are therefore forced to conclude that whatever
success has attended the application of the theory of
solid solutions to other processes, the theory can scarcely
without modification be accepted as giving an explanation
of the process of dyeing.

BIBLIOGRAPHY.

J. H. VAN'T Hoff. Zeitschrift fiir physikalische Chemie, v., 322

(1890).
A. VAN BlJLERT. Ibid., viii., 343 (1891).
O. N. WlTT. Fdrber-Zeitung, i. (1 890-91).
C. T. HEYCOCK and F. H. Neville. Journal of the Chemical

Society, Ixi., 888 (1892).

E. A. Schneider. Zeitschrift fiir physikalische Chemie, x., 425

(1893).
A. Ferratini and F. GARELLI. Gazzetta chimica italiana, xxii.,

ii., 245 ; xxiii., i., 442 (1893).

F. GARELLI. Ibid., xxiii., ii., 354 (1893).

F. GARELLI. Zeitschrift fiir physikalische Chemie, xviii., 51 (1895).
F. W. KtJSTER. Ibid., xii., 508 (1893); xiii., 445 (1894) 5 xv»-> 357
(1895).

F. W. KtJSTER. Liebigs Annalen, cclxxxiii., 360 (1894).

C. HoiTSEMA. Zeitschrift fiir physikalische Chemie, xvii., 1
(1895).

G. C. Schmidt. Ibid., xv., 56 (1894).

E. Beckmann and A. Stock. Ibid., xvii., 120 (1895).
J. M. VAN BEMMELEN. Ibid., xviii., 331 (1895).
G. V. GEORGEVICS. Monatshefte fiir Chemie, xv., 705 (1894).
G. v. Georgevics and E. Lowy. Ibid., xvi., 345 (1895).

James Walker.

THE STELAR THEORY; A HISTORY AND A

CRITICISM.

PART I.

IN the study of the histological anatomy of plants, apart
from the structure of the individual cell, the greatest
advances of the last two decades have been made rather by
the establishment of new points of view than by the dis-
covery of new facts. Twenty years ago the solid founda-
tions of the subject had been securely laid, and a consider-
able portion of the imposing fabric of histological detail
which now rests upon them had already been built up.
This fact is most clearly brought out by the masterly
summary of existing anatomical knowledge published by
De Bary in 1877. But splendid monument as it is of its
author's unsurpassed knowledge of his subject, there can be
few who have not felt that the Vergleichende Anatomie
is, as a whole, essentially unreadable. Compare it, in
imagination, with Sachs' Vorlesungen or with Haber-
landt's Physiologische Pflaiizenanatomie , and we are
forced to recognise that De Bary's work is rather an ency-
clopaedia than a piece of great scientific literature. The
cause is to be found in the simple fact that there did
not exist in 1877 a philosophy of the morphological aspect of
the subject capable of informing " an epitome of the pre-
sent knowledge of 'the Anatomy of the Vegetative Organs
of Vascular Plants,' " as the idea of adaptation informed the
works of Sachs and Haberlandt.

It is nothing less than the establishment of such a
philosophy that we now owe to the great Frenchman, Van
Tieghem. The most important part of his ideas is con-
tained in what we may call the Stelar Doctrine of Vascular
Tissue, and it is with this that we shall here be exclusively
concerned.

Although the foundations of the stelar theory were laid
many years ago, outside France it has made its way very
slowly. In Germany even now it is apparently ignored

134 SCIENCE PROGRESS.

by the majority of anatomists, notwithstanding its accept-
ance by the most brilliant of German contemporary in-
vestigators.

In England, though these ideas have recently been
made familiar to the student by more than one of our lead-
ing botanists, their discussion has still the interest of com-
parative novelty. And although the general idea of the
stele as a morphological unit is simplicity itself, yet the
application of this idea is in some cases by no means easy,
so that not only does Strasburger's interpretation of certain
facts differ from Van Tieghem's, but the author of the
theory has himself been led to modify his original views in
an important manner. The possibility of such a difference
in the interpretation of facts which are undisputed seems to
spring, if we may say so without presumption, from a
certain want of definiteness in the apprehension of the
criteria legitimate to their interpretation.

To investigate these criteria and to endeavour to as-
certain their relative validity is one of the primary objects
of the present paper.

We shall begin with an account of the development of
the stelar doctrine.

HISTORY OF THE STELAR DOCTRINE. FIRST PHASE—
THE IDEA OF THE CENTRAL CYLINDER.

In 1 8 70- 1, Van Tieghem published, in the Annales des
Sciences Nattirelles, a memoir (1) which was to have been
the first of a series entitled " Recherches sur la syme.trie
de structure des plantes vasculaires". This instalment con-
sisted of a general introduction setting forth the plan of
the whole work, followed by 274 pages devoted to an ex-
tended anatomical account of the root, in vascular plants.

The introduction is of the Greatest interest. The
author tells us how he wished to obtain anatomical defini-
tions of root, stem, and leaf, in order to give a basis to the
study of comparative anatomy. These definitions are to
be framed in accordance with the different kinds of sym-
metry exhibited in the arrangement of the vascular strands
in the three organs, to each of which a separate memoir

THE STELA R THEORY. 135

is to be devoted. The results so obtained are to be
applied, in a further series of memoirs, to the solution
of a number of morphological problems, such as the true
nature of tendrils, tubers, spines, phylloclades, ovules, etc.,
and finally, to the elucidation of the laws of symmetry
governing the structure and relations of the ideal colony
that would be formed if every seed germinated in situ.

This elaborate scheme for "un cercle d'etudes an-
atomiques complets et fermes " enables us to understand
the strength and the weakness of the author's stelar theory.
The imperative desire to reduce the anatomy of vascular
plants to a perfect system depending upon simple laws of
symmetry governing the arrangement of the vascular tissue,
has been the means of giving us a doctrine, luminous indeed,
and of wide significance, but scarcely of that rigidly uni-
versal application which its author claims. But here again,
as is so often the case in the history of science, the attempt
to work out logically the various implications of such a
theory, has been of the utmost value in clearing our ideas
and extending knowledge, not only by stimulating to the
discovery of new facts, but by forcing us to examine the
foundation of our conceptions.

Of Van Tieghem's scheme, as it stood in 1870, how-
ever, only the first memoir, that on the root, was ever
written. The author demonstrates the fundamental identity
of structure in the roots of all vascular plants, and obtains his
anatomical definition based on the symmetry of the vascular
system. He shows that the vascular tissue of a young root
forms a central cylinder which contains near its periphery
" faisceaux liberiens" (phloems) alternating with "faisceaux
vasculaires" (xylems) united by "cellules conjonctives ".
Hence the vascular system is symmetrical in relation to a
line, which is the organic axis of the organ. The stem
agrees with the root in this last point, but on the other
hand has its "faisceaux libero-vasculaires," " reunis directe-
ment par le parenchyme primordial ". Where the main
root passes into the main stem there occurs a "cessation du
tissu conjonctif special, qui se trouve remplace par le
parenchyme primitif ". This sentence is specially interest-

136 SCIENCE PROGRESS.

ing because it shows that when it was written Van Tieghem
had no idea of a central cylinder in the stem.

Two years later, however, in 1872, in describing (2)
the transition from root to shoot in Tagetes patiila, he
writes how the " membrane protectrice " (endodermis) is
continued up into the stem, retaining its characteristic
thickenings, and immediately internal to it the "membrane
rhizogene" of the root (later named the pericycle) is also
found in the stem still giving rise to rows of lateral roots,
one row arising from each interval between two bundles.
Opposite the bundles, however, he holds that the "membrane
rhizogene" is interrupted, since here the endodermis abuts
directly on the group of fibres capping the bundle, fibres
which in accordance with the current opinion he considered
to belong to the phloem. Here then we have the first
clear description of the continuation of the central cylinder
of the root into the stem, and the idea of this continuation
is the fundamental idea of the stelar theory. It is most
clearly expressed in a note on p. 112, " Ainsi, et j'insiste
sur ce point, la tige est, comme la racine, et dans toute son
etendue, composee d'un cylindre central et d'un parenchyme
cortical limite en dehors par un epiderme, en dedans par
une membrane protectrice ou endoderme ".

The generality of this condition is further insisted upon :
" Le caractere sur lequel je viens d'appeler l'attention se
retrouve dans la tige de la grande majorite des plantes
vasculaires, mais il souffre pourtant quelques exceptions.
M. Caspary a montre, en effet, que dans quelques plantes
(Minyanthes trifoliata, Adoxa moschatellina, Bi-asema
peltatd) chaque faisceau constitutif de la tige est indivi-
duellement entoure par une membrane protectrice a cellules
plissees (' Bemerkungen liber die Schutzscheide,' in Pring-
scheims Jahrbucher, 1865-66, iv., p. 10 1). J'ai retrouve le
meme fait sur quelques autres plantes, notamment sur
r Hydrocleis Humboldtii. Dans ce cas, il n'y a pas non
plus de membrane rhizogene dans les entrenceuds de la
tige, et il n'existe aucune solution de continuity aucune
distinction reelle entre le parenchyme cortical et la moelle '
(p. 113). This paragraph shows clearly that thus early

THE STELA R THEORY. 137

Van Tieghem had recognised the condition which he
afterwards described as " astely ".

The "membrane rhizogene," now considered, under the
name of pericycle, as forming merely the external layer of
the conjunctive tissue of the cylinder, was at that time
treated as a region external to, and distinct from, the rest
of the parenchyma, to which the name " conjonctif " was
given. But the clear recognition of the existence of an
individualised stem cylinder, forming a direct continuation,
tissue for tissue of that of the root, was the first and funda-
mental step in the evolution of the stelar idea.

Little progress was made during the next ten years in
the development of this conception.

Falkenberg (3), in 1876, showed that the " Aussen-
scheide " in monocotyledonous rhizomes corresponds with
the " pericambium " in roots, both in position and role ;
and Mangin (4) in 1882 entirely confirmed his results and
showed that not only adventitious roots but also the
" reseau radicifere " arises from this layer, which he calls
the " couche dictyogene ".

In 1882 Van Tieghem published a short paper (5) in
which, a propos of the Cucurbitacese, he gives conclusive
reasons, based upon grounds of comparative anatomy, for
regarding the fibres in the stem, hitherto called primary
"bast fibres," as really belonging to the "membrane
rhizogene ". With these extended limits, this layer forms a
complete investment of the stem cylinder, just as the peri-
cambium does of the root cylinder. Since the one layer is
the direct continuation of the other, and the two correspond
very largely in function as well as in position, it is clearly
desirable that they should have a common name. For this
purpose Van Tieghem introduced the word pericycle, which
was to supersede the various terms "pericambium,"
" Aussenscheide," "membrane rhizogene," "couche dictyo-
gene," etc., applied by various writers to the same layer in
various plants and parts of plants, according to its various
histological characters and functions. The importance of
this introduction of the conception of the pericycle was of
course very great, since it fixes more accurately the external

138 SCIENCE PROGRESS.

limit of the cylinder, and thus brings into greater promi-
nence the idea, already clearly stated in 1872, of an indi-
vidualised stem cylinder in direct continuity with that of
the root.

The term has eventually, though very slowly, found
its way into general use.

In 1884 Morot, a pupil of Van Tieghem, published the
results of a research (6) devoted to a comparative investiga-
tion of the pericycle in both root and shoot.

The publication of Morot's paper brings to an end what
we may call the first phase in the development of the stelar
idea.

SECOND PHASE— POLYSTELY AND ASTELY.

The second phase was inaugurated in an investigation (70)
by Van Tieghem and his pupil Douliot, of the anatomy of the
stem of various species belonging to the genus Primula. Their
observations were carried out on a number of new species from
the East, as well as on many old species, making together a
total of 114. They resulted [yd) in a division of the aggre-
gate genus Primula L., into two segregates, Primula Tourn.
and Auricula Tourn., as had been already done by Tourne-
fort, but now based on a fundamental difference in the
structure of the stem of the two segregate genera. While
the stem of the species belonging to Primula possesses
a single normal central cylinder in its whole extent, the
narrow cylinder of the hypocotyl of an Auricula, instead
of dilating in the ordinary way above the level of the coty-
ledons, gives rise by successive bifurcations to two or more
vascular strands, each surrounded by an endodermis and
possessing" the structure of the single hypocotyledonary
cylinder. In the genus Gunnera {Haloragece) a similar
state of things obtains. These facts were, in the main,
already known, having been investigated by Vaupell,
Kamienski and Reinke. The opinion of these authors
was, however, that the separate vascular strands were vas-
cular bundles of the " concentric " type with peripheral
phloem, comparable for instance to those found in the
cortex of certain Mclastoniace<z ; and this was the view

THE STELA R THEORY. 139

taken by De Bary in his classical Vergleichende Anatotnie.
The numerous vascular strands in the rhizomes of most
Leptosporangiate Ferns were regarded by De Bary in the
same light.

But Van Tieghem, having, as we have seen, come
to regard the central cylinder rather than the bundle as
the morphological unit of vascular tissue in both root and
shoot, was now led to the conclusion that in Auricula,
Gunnera and the majority of Ferns 1 we have really to
deal with a splitting- of the single cylinder of the hypocotyl,
as we trace it upwards, by successive bifurcations, into a
number of such cylinders (jc and 8). Van Tieghem
and Douliot proposed to call such a cylinder a stele (Greek
<7r/;X»7, a column). A root or a stem containing one such
stele would be monostelic, if it contained more than one
polystelic. A third case was distinguished. If the cylinder
of the hypocotyl breaks up, as it is traced upwards, into
its component bundles, each of which is surrounded by a
special endodermis, the cylinder, according to our authors,
no longer exists ; the stem is astelic. This case, already
described in 1872, obtains in the stems of various Ranun-
culacece, in Nymphceacece, in Hydrocleis, in some species of
Equisetum, etc., as well as in the majority of petioles and in
blades of all leaves.

Cases of Polystely fall into two groups. First, where
on a transverse section the various steles are seen to be
completely separate, we have a state of dialystely. Secondly,
where the steles are united laterally, so as to form a more or
less complete ring in transverse section, enclosing a more or
less isolated portion of extra-stelar tissue, which occupies the
centre of the ring, we have a state of gamostely. These
two conditions are not to be sharply separated, since the
steles of all polystelic stems show more or less frequent
lateral unions, and the gamostelic condition is simply a
case where these unions are very frequent and persistent.

1 Leclerc du Sablon in 1890 (9) worked out the connections, in
several Ferns, of the single hypocotyledonary cylinder with the cylinders
of stem.

140 SCIENCE PROGRESS.

We may tabulate the results thus obtained as follows: —

Monostely. — A single central cylinder. All roots and
hypocotyls, nearly all Phanerogamic stems, and stems of
many Vascular Cryptogams.

Polystely. — More than one cylinder. Stems of most
ferns, most species of Selaginella, and among Phanerogams
of Auricula and Gunner a}

(a) Dialystely.— Steles separate for most of their
course. Most Ferns Selaginella and. Auricula ursi, etc.
Gunnera.

(6) Gamostely. — Steles united laterally for most of their
course. Marsilia, Pilularia, Pteris aurita, etc. Auri-
cula japonica, etc.

Astely. — No cylinder. Leaf blades, most petioles,
stems of some species of Equisetum and Ranunculus^
stems of Hydrocleis, Ophioglossum, Limnanthonum, Nym-
phceacece, etc. (yc).

The publication, in 1890-91, of the second edition of
Van Tieghem's Trait e" de Botanique (10), which contains a
full exposition of the stelar doctrine on the lines indicated,
may be said to mark the close of the second phase in the
development of the theory.

THIRD PHASE— EXTENSIONS AND MODIFICATIONS.

The third phase, from that date to the present time, has
been occupied by various developments and modifications of
the doctrine on the part of the author and his pupils, and has
been marked by considerable criticism, mainly of these
newer developments.

The first line of research that calls for notice is a re-
investigation of the conjunctive tissue of the typical central
cylinder of the flowering plant. This has led Flot (11) to

1 In a paper recently communicated to the Linnean Society, Mr. B.
G. Cormack describes cases of polystely met with in the adventitious roots
of three genera of Palms, viz., Areca, Cocos and Verschaffeltia. It appears
that the single stele of the root splits, as it is traced downwards, into a ring
of separate steles. Later on these steles again pass over into a single
cylinder. This seems to be an important modification of Polystely as
described by Van Tieghem and Douliot, and Leclerc du Sablon.

THE STELA R THEORY. 141

add a new region to those already distinguished. He
finds a zone situated at the periphery of the pith, i.e., just
internal to the ring of bundles, corresponding exactly to
the pericycle external to the ring, as well characterised
histologically as the pericycle itself, and indeed resembling
the latter very closely in structure and role. This zone,
the perimedullary zone, is according to Flot (and his
figures entirely support this) separate in development from
the pith proper, or internal conjunctive, and belongs rather
to the hollow cylinder of tissue (the "thickening ring " of the
older German anatomists) giving rise to the bundles and
the conjunctive immediately surrounding them {external
conjunctive). It is impossible sharply to separate the peri-
medullary zone on the one side, just as Morot found it
impossible to separate the pericycle on the other, from the
ray tissue, and we should rather regard the contrast of
the pith with the external conjunctive tissue, as of greater
importance than the division of the latter into pericycle,
rays and perimedullary zone, which are in the main
topographical regions marked out by the limits of the
bundles. In many adult stems it is however impossible to
fix the limits of external and internal conjunctive, just as
it is often impossible to fix the limits between external con-
junctive and cortex. Flot is of opinion that this is owing
to a growth in breadth of the cells of the external conjunc-
tive continued longer than in the pith, the whole of the tissue
of the cylinder thus becoming approximated in size and
shape. This same cause, together with a masking of the
endodermal thickenings (in cases where these are originally
present) by a general thickening of the walls of all the
parenchyma cells may very conceivably account for the
frequent absence of the obvious limit between cortex and
cylinder, though we are not aware that such an occurrence
has been either established or suggested.1 Further in-
vestigation on this point, as well as on the separation of
the regions in root cylinders with a well-developed con-

XI now find that Sanio (24, pp. 371-2) states that this is practically
what occurs in the stem of Ranunculus acris.

i42 SCIENCE PROGRESS.

junctive system, is much needed to complete our know-
ledge of these matters.

An important modification of the theory of steles has
been made by Van Tieghem himself in extending the use
of the term astely so as to make it include the state of
things obtaining in the stems of all species of Equisetum
(12), and of 0 p hio gloss ace ce (13).

Let us take first the case of Equisetum. Well-
marked endodermes are found in the stems of all species,
but their disposition, which was fully worked out many
years ago by Pfitzer, is very various, not only in different
species, but in different parts of the stem of the same
species. There are three types of arrangement. In the
first each vascular bundle is surrounded by a special endo-
dermis ; in the second the ring of bundles is bordered within
and without by a general endodermis ; and in the third
the outer endodermis alone is present. In the second
edition of the Traite Van Tieghem assigned the first
two conditions to the astelic, the third to the monostelic
type, but in a paper (12) published in the same year (1890)
he calls attention to the fact, discovered by Pfitzer, that
all the species possess, at their nodes, the first or second of
the arrangements in question. He therefore concludes
that all belong really to the astelic type, and that where,
for instance, the second type, just above a node, passes
back into the third, we have simply a case of the dis-
appearance of the special characters of the inner endo-
dermis, which must still be supposed to exist. The " mono-
stely" is only apparent, and the tissue bordering the
central canal of the stem, internal to the inner (theo-
retical) "endodermis," is not in reality pith, but rather
" inner cortex" (extra-stelar tissue). The first of the three
arrangements is to be called dialydesmic, since each bundle
with its sheath of conjunctive is separate ; the second and
third gamodesmic, since the conjunctive tissue surrounding
the bundles is in lateral confluence.

Turning now to the Ophioglossacece we have a similar
argument (13). The stem of Ophioglossum vulgahtm,
below the level of the first leaf, is monostelic, but above the

THE STELA R THEORY. 143

first leaf contains five separate bundles each with a separate,
though feebly suberised, endodermis. Hence it was
treated by Van Tieghem, in the Traits, as astelic. In
Botrychium Lunaria, whose stem is also monostelic at the
base, the endodermis, after the departure of the first leaf
trace, does not close round each separate bundle but
becomes as it were invaginated into the cylinder, so that
the vascular tissue forms on transverse section a horse-
shoe bounded by the endodermis. The free edges of the
horseshoe meet, as we pass up the stem, and the inner
portion of the endodermis becomes entirely separated from
the outer, so that we have an equivalent of the second or
gamodesmic condition found in the stems of Eqtiiseta.
Higher up the inner endodermis loses its thickenings, just
as in some Equiseta, and this gives us an apparently
monostelic condition. In accordance with his revised
view, Van Tieghem considers that OpJiioglossum has an
astelic-dialydesmic stem, while those of Botrychium and
Helminthostachys are astelic-gamodesmic.

THE STATUS OF THE STELE CRITICISM.

It will be most convenient to introduce here a critical
investigation of the stelar theory as thus modified by its
author, and so far as it depends upon the morphological
interpretation of the arrangement and relations of vascular
tissue in the adult organs of vascular plants ; deferring for
the present a consideration of the developmental facts
bearing upon the theory.

There is no need to discuss at any length the funda-
mental conception of the stele arrived at in the period which
we have called the first phase of development of the idea.
It depends upon the tracing into the stem of the root
cylinder, and upon the demonstration that its characters as
a cylinder are maintained in the latter. This demonstration,
begun, as we have seen, in 1872, eventually led to the
explicit recognition of the fact that the system of bundles
forming the central cylinder possesses morphological charac-
ters much more constant than those of the vascular bundle,

144 SCIENCE PROGRESS.

and is hence more worthy to be taken as the morphological
unit of vascular tissue. It is indeed impossible to give a
morphological definition of a vascular bundle at all. " From
the very first those bundles which consist essentially of
definitely arranged groups of tracheae and sieve tubes . . .
have been called vascular bundles" (14, p. 232, Eng. ed.).
But thus defined, a "vascular bundle" has no constant
histological characters beyond the fact of containing both
xylem and phloem. According to the arrangement of these,
bundles have been classified as radial, concentric, collateral,
etc. Such an arrangement brings together vascular strands
of very different orders of complexity. In the first place
it associates the axial cylinder ("radial bundle") of a root,
possessing a number of quite distinct xylem and phloem
strands, with the "collateral bundle" of a Phanerogamic
stem, formed of a single strand of xylem and phloem in close
association, the latter being continuous moreover with a
portion only of the former. Again it associates even more
closely under the term " concentric bundle " the vascular
strands found in the stem of Auricula, Gunnera and Ferns
with those of quite different structure found in the pith and
cortex of Melastomacecz, etc.

Such a classification is clearly, from a morphological point
of view, quite artificial. But if we extend the use of the term
bundle, as is often done, so as to include strands of tracheae
alone, and of sieve tubes alone, we can retain it as a con-
venient word without morphological connotation, and
applicable to any strand of tissue belonging to the vascular
system. And we may then qualify the word by any adjec-
tive we choose without morphological implication. Thus we
may speak of the composite radial bundle of the root as
composed of separate xylem bundles and phloem bundles
alternating at its periphery ; of the concentric bundle of the
stem of an aquatic plant as sometimes composed of separate
collateral bundles, in other cases consisting simply of a con-
tinuous cylinder of phloem surrounding a central strand of
xylem ; of the concentric bundle of a fern petiole gradually
passing to the collateral type as we trace it into the lamina,
and so on. Meanwhile the study of the homologies of the

THE STELA R THEORY. 145

various strands is quite a distinct matter, and requires a
distinct terminology.

THE BOUNDARY OF THE STELE.

The acceptance of the central cylinder in the " mono-
stelic " stem as a region of the first morphological rank is
now very general. The only criticism which we have to
consider is that which calls attention to the frequent want
of definiteness about its external limit, and is inclined on
this ground to question its individuality. This want of
definiteness arises from the absence, in many adult stems,
of the special characters of the endodermis (innermost
layer of the cortex), often combined with an identity in
size, shape and characters of cell-membrane between
the cells of the cortex and those of the conjunctive. Such
a state of things obtains, to take a single instance, in the
stem of Ranunculus repens. A transverse section of such
a stem shows the separate bundles imbedded in a homo-
geneous ground tissue, and to speak of a well-marked central
cylinder is to speak of that which does not, in fact, exist.

Now this, as it stands, is a perfectly legitimate criticism,

and its force as against the general validity of the stelar

idea depends simply upon the greater or less generality of

the condition described. Van Tieghem (10, p. 752) states

that when, after the formation of the endodermis, the stem

undergoes considerable intercalary growth, the folds on

the radial walls of the endodermal cells become stretched out

so that they become difficult or impossible to see. In other

cases no suberisation of the radial walls occurs, and then,

unless the endodermal cells are distinguished by possessing

starch, it is admitted that the limit of the cylinder is difficult

to determine, but says Van Tieghem {Joe. eit.) : " il reste la

forme differente des cellules ". This, however, as has been

said, is by no means always obvious. A possible cause of

such a condition, assuming the limits of the young cylinder

to be well defined, has already been suggested, but

new investigations are necessary to determine the point.

If, for the sake of argument, we make the opposite assump-

10

146 SCIENCE PROGRESS.

tion, that the vascular bundles are sometimes differentiated
in the middle of a homogeneous ground tissue, no trace
of a special endodermis or pericycle being visible at any
time, we could not predicate the existence, in such cases,
of a central cylinder in the stem. And further, if such
a condition obtained in the majority of instances (certainly
an unlikely supposition) we should not, of course, be
justified in predicating the general existence in the stem
of a central cylinder, and this would necessitate such a
radical modification in the generalised statement of the
facts, that the stelar idea would lose the greater part of
its significance. We shall have to recur to a discussion
of the limit of the cylinder, but these simple considera-
tions are insisted upon here, because they are apparently
lost sight of in much of the current writing of Van Tieg-
hem's adherents. It seems to be implicitly assumed that if
a good anatomical distinction can be made in a certain
number of cases, it is permissible to generalise the distinc-
tion and erect it into a morphological doctrine. The
existence of those cases to which the doctrine does not
apply is either ignored, or the distinction is said to be
" theoretical ". There is of course no such thing as a true
"theoretical" distinction which is not also actual. The
fallacy arises from a tendency to regard all morphological
doctrine as of absolute value, whereas its value is never
anything but relative. What we have to decide in any
given case is the amount of this relative value, and whether
that amount is sufficient to make the doctrine express a
general truth so far as the objects under consideration are
concerned.

The foregoing reflections lead us naturally to consider
those cases which Van Tieghem himself excepts from the
application of the stelar doctrine, namely, the cases of
"astely". Already in the earliest paper containing the
germ of the stelar idea we find certain cases not covered
by the general statement of the existence of a cylinder in
the stem. In 1886 these cases together with other similar
ones were called astelic, and more recently still the concep-
tion has been further elaborated.

THE STELA R THEORY. 147

The conception is governed throughout by the idea of
the endodermis as a definite morphological layer, always
separating" stelar from extra-stelar tissue. And the en-
dodermis is to be recognised by the suberised thicken-
ings on its radial walls. It is simply by the disposition of
layers of cells so thickened that we are supposed to be
able to distinguish the various arrangements described.
It is easy to show that this criterion is quite illegitimate.
The term endodermis is defined by Van Tieghem as the
innermost layer of the cortex which " offre frequemment "
the special character in question (10, pp. 738-9). Not
only, however, do cell layers with the same character
occur in quite other situations {e.g., in the middle of many
periderms), but the innermost layer of the cortex certainly
does not always possess it. So that these thickenings
cannot be used to mark a layer of invariable morpho-
logical value. And even in Equisetum, Van Tieghem does
not keep to his own criterion. For when the " astelic
gamodesmic " passes to the apparently monostelic con-
dition we are told that the inner endodermis is still
present though its special characters have disappeared.
But, we may well ask, if such great importance is to be
attached to these special characters as to justify us in
founding new types of structure simply upon the disposition
of the layers exhibiting them, why should we be suddenly
asked to recognise as equivalent a layer which does not
exhibit them ? The criterion becomes completely chimeri-
cal.

Strasburger (15) has pointed out that an endodermoid
layer is an air-tight barrier which does not prevent the
passage of water through its cells. Such a layer is found
in a position to shut off the water-conducting system of a
plant from its air-containing lacunar system, but this posi-
tion may vary within the same genus [Ranunculus,
Equisetum), and has no necessary connection with any
morphological region. As a matter of fact it is most often
formed from the inner layer of the cortex, but may be
developed from conjunctive tissue, or even (leaf of Isoetes)
from intra-fascicular parenchyma. Since the innermost

148 SCIENCE PROGRESS.

layer of the cortex does not always possess the special
thickenings which give it the right to be called a
" membrane," Strasburger objects to Van Tieghem's re-
definition of the word endodermis, and proposes to sub-
stitute the term Phloeoterma, to be applied to the inner
layer of the cortex, i.e., to be used in the strictly morpho-
logical sense, whether this inner layer has special characters
or not, and to reserve the term endodermis in accordance
with its original sense for any sheath or membrane com-
posed of cells with suberised radial walls or other dis-
tinctive thickenings, without reference to its position.
This revised terminology certainly helps us to get rid
of the confusion of thought manifested in Van Tieg-
hem's use of the word endodermis. Strasburger concludes
that as all species of Equisetum agree in possessing a ring
of simple collateral bundles, they should all be considered
monostelic, whether the phloeoterma be developed as a
general endodermis, or each bundle possess a special
endodermis, the phloeoterma having no characters by which
it can be distinguished. The same considerations would
apply to the genus Ranunculus and the other cases of
"astely ". While we must fully admit the general force of
his argument on the ground of comparative anatomy, it is
difficult to agree with the following sentence : " Die
Grenze der Rinde gegen den Centralcylinder ist dort wo
sie sich nicht besonders als Endodermis oder Starkescheide
markirt, nur theoretisch zu ziehen, dieselbe ist aber flir alle
Falle festzuhalten ': (15, p. 484). How is one to "hold
fast " a limit which one cannot distinguish ? We can only
refer to the remarks which have been already made upon
this subject, but we shall briefly recur to the subject in
considering the development of the stele.

Leaves furnish us with excellent examples of the frequent
impossibility of separating stelar from extra-stelar tissue.
Putting aside those cases in which one or more steles
from the polystelic stem directly enter the petiole
[Gunncra, Ferns), we have to consider the ordinary
case in a flowering plant, where we have one or more
bundles leaving the cylinder and passing into the petiole.

THE STELA R THEORY. 149

These bundles are accompanied by a certain amount of
closely associated parenchyma belonging to the external
conjunctive of Flot, a tissue which in the leaf Van Tieghem
now calls peridesm (16). The bundles are sometimes
arranged in a ring, and the whole may be, though com-
paratively rarely, surrounded by an endodermis. The
petiole is then, according to Van Tieghem (10, p. 842),
monostelic. In the commoner case where each bundle has
an endodermis of its own the petiole is astelic.

Strasburger prefers the term schizostelic (15), since the
stelar tissue of the petiole represents a separated portion or
portions of that of the stem. To such a portion he gives the
name schizostele or schistostele \ at the same time denying the
existence of monostelic petioles in Phanerogams on the
ground that the apparent pith of the petiole is continuous
with the cortex, and not with the pith, of the stem. This
last contention brings forward a difficult position. Is it de-
sirable to introduce the question of continuity at all ? If we
have in the petiole a structure apparently identical with that
which we have agreed to call monostelic in the stem, should
we be satisfied to call it monostelic here also, without con-
sidering the connections of its parts with those of the stem ?
The strength of Strasburger's position lies in the fact that
the continuity, region for region, of the cylinder of root
and stem is really the basis of the stelar idea. The origin
of the difficulty is to be found in the tendency of a petiole,
where it is subject to the same conditions as a stem, to
assume the characters of a stem, and among them the
arrangement of its vascular tissue according to a radially
symmetrical type. We might, perhaps, fitly call such a
structure a pseudostele.

The mesophyll of the leaf (corresponding with the cortex
of the stem) which surrounds the smaller vascular bundles,
often has its innermost layer or phloeoterma, which abuts

1Van Tieghem has since (17, p. 285) used the word meristele for
Strasburger's " schizostele," and applied the latter term to the portion of
stelar tissue enclosed by each special endodermis in an "astelic" stem.
This seems an unwarrantable diversion of the meaning of Strasburger's
term.

i5o SCIENCE PROGRESS.

immediately upon the peridesm of the bundle, specially
characterised. The cells of the phloeoterma are often de-
prived of chlorophyll, or this is confined to the side walls,
and these walls may also be suberised. It is, however, a
rare case for such layers to be united in a continuous
system with the phloeoterma of the stem, and thus to shut
off completely, by means of a continuous membrane, the
entire stelar system of the plant from its cortical tissue.
This state of things obtains, however, in Pinus and some
dicotyledonous genera, e.g., Galium. In most dicotyledo-
nous petioles endodermoid layers, if distinguishable at all,
are often incomplete and not necessarily formed from the
phloeoterma. A closed sheath to the bundles is, however,
often formed in Angiosperm petioles by thickened peri-
desmic (stelar) tissue, such a sheath being called by Stras-
burger a stelolemma (15). The ensemble of the phenomena
shows us, clearly enough, that the endodermis, in its original
sense, cannot be taken here, any more than in the stem,
as a layer of constant morphological value. The phloeo-
terma may be distinguishable by endodermal or other char-
acters, but on the other hand, it may not.

The main fact in regard to the vascular system of the
leaf is one which was pointed out by Van Tieghem in 1870.
The system is bilaterally symmetrical in relation to the
plane including the organic axes of both leaf and stem,
and not, like that of root and stem, radially symmetrical
about its organic axis. The designation of the continuous
cylinder of root and stem as a stele and of each bundle or
the whole bundle system of the leaf as a schistostele or
meristele is in complete accord with this general fact. But
we must not disguise from ourselves that both the stele and
the meristele may not exist in the adult as sharply separated
structures.

A. G. Tansley.
( To be contimted. )

ON SOME APPLICATIONS OF THE THEORY
OF OSMOTIC PRESSURES TO PHYSIO-
LOGICAL PROBLEMS.

PART II.

IN my previous article I gave some account of a research
by Heidenhain in which this observer, after drawing
certain deductions from the theory of osmotic pressures, shows
that the phenomena of absorption from the intestinal canal are
irreconcilable with these deductions, and are therefore not
susceptible of a mechanical explanation, but must be as-
cribed to the active intervention of cells. Since analogous
problems to those discussed by Heidenhain are continually
coming before us in physiology, it is important that we
should have a clear idea of the factors which are involved
in the passage of water or dissolved substances across
membranes. I therefore propose to reproduce Heiden-
hain's statements, and then to consider how far they are
true for the special cases which occur in the body.

These statements are as follows : —

i. If two watery solutions with the same osmotic pres-
sure are separated by a membrane through which diffusion
can take place, no change in volume occurs on either side
of the membrane.

2. If the solutions on either side of the membrane are of
unequal osmotic pressure, water passes from the side where
the pressure is less to the side where the osmotic pressure
is greater.

3. The osmotic pressure of a solution is equal to the sum
of the partial pressures of the various dissolved substances.

4. If the solutions on the two sides of the membrane
have the same total osmotic pressure but unequal partial
pressures of their various constituents, each constituent of
the solution passes from the side where it has the higher
partial pressure to the other side. No change in the volume
of water on the two sides takes place.

Of these four statements only one (No. 3) is absolutely

152 SCIENCE PROGRESS.

correct. The other three are only correct under certain
defined conditions which are rarely fulfilled in the body.
There are factors at work which have been practically dis-
regarded by most of the recent workers on the subject, and
which may tend to produce movement of fluid in apparent
opposition to the difference of osmotic pressure. Instances
of such cases are afforded in a paper by Lazarus Barlow, to
a consideration of whose work we shall shortly return.

There can be no doubt that in the phenomena of trans-
ference of fluid or dissolved substances across a membrane
the nature of the membrane itself is all-important. I will,
therefore, shortly run through the various modes in which
interchanges may take place across membranes of varying
permeability. We shall see that the close analogy which
exists between substances in solution and gases, when
dealing with "semi-permeable" membranes, is also borne
out by experiment when used to predict the behaviour of
solutions separated by such permeable membranes as occur
in the body.

The simplest case is that in which two fluids are sepa-
rated by a perfect semi-permeable membrane that permits
the passage of water but is absolutely impermeable to dis-
solved substances. In this case the transference of water
from one side to the other depends entirely on the difference
of osmotic pressure between the two sides.

m.

A

B

If we suppose two vessels, A and B, separated by such
a membrane, A containing a solution of a and B a solution
of (5, water will pass from A to B so long as the osmotic
pressure of /3 is greater than the osmotic pressure of the
solution of a. If B be subjected to a hydrostatic pressure
greater than the osmotic difference between the two fluids,
water will pass from B to A until the force causing filtration
or transudation (the hydrostatic pressure) is equal to the

THE THEORY OF OSMOTIC PRESSURES. 153

force causing absorption into B (the difference of osmotic
pressures). Under no circumstance will there be any trans-
ference of salt or dissolved substance between the two sides.
Such semi-permeable membranes as this, however, rarely
occur in the body. It is possible that the external layer of
the cell-protoplasm may in some cases resemble the proto-
plasmic pellicle of plant-cells in possessing this "semi-per-
meability " ; but in nearly all cases where we have a mem-
brane made up of a number of cells, it can be shown that
such a membrane permits the free passage of at any rate a
large number of dissolved substances.

Let us now consider what will occur when the two solu-
tions A and B are separated by a membrane which permits the
free passage of salts and water. If the osmotic pressure of
B be higher than A at the commencement of the experi-
ment, the force tending to move water from A to B will be
equal to this osmotic difference. But there is at the same
time set up a diffusion of the dissolved substances from B
to A and from A to B. The result of this diffusion must
be that there is no longer a sudden drop of osmotic pressure
from B to A, and the result of the primary osmotic difference
on the movement of water will be minimised in proportion
to the freedom of diffusion which takes place through the
membrane. Now let us take a case in which A and B re-
present equimolecular and isotonic solutions of o and /3.
It is evident that the movement of water into A will vary
as Ap - Bpl = O. But diffusion also occurs of a into B and
of (3 into A. Now the amount of substance diffusing from
a solution is proportional to the concentration, and there-
fore to its osmotic pressure, as well as to its diffusion
coefficient.

Hence the amount of a diffusing into B will vary as
Aft . ak (when k is the diffusion coefficient).

In the same way the amount of (3 diffusing into A will
vary as Bp, (5k'.

Hence if ak is greater than (3k', i.e., if a is more diffusible
than (3, the initial result must be that a greater number of

1 Ap = osmotic pressure of A, etc.

154 SCIENCE PROGRESS.

molecules of o will pass into B than of /3 into A. Hence
the solutions on the two sides of the membrane will be no
longer equimolecular, but the total number of molecules of
a + (3 in B will be greater than the number of molecules of
a + j3 in A, and this difference will be most marked in the
layers of fluid nearest the membrane. The result therefore
of the unequal diffusion of the two substances is to upset
the previous equality of osmotic pressures. The layer of
fluid on the B side of the membrane will have an osmotic
pressure greater than the layer of fluid in immediate contact
with the A side of the membrane, and there will thus be a
movement of water from A to B. Hence if we have two
equimolecular and isotonic solutions of different substances
separated by a membrane permeable to the dissolved sub-
stances, there will be an initial movement of fluid towards
the side of the less diffusible substance.

We have an exact parallel to this in Graham's familiar
experiment in which a porous pot filled with hydrogen is
connected by a vertical tube with mercury. In consequence
of the more rapid diffusion outwards of the hydrogen than
of atmospheric air inwards, the pressure within the pot sinks
below that of the surrounding atmosphere, and the mercury
rises several inches in the tube. We must therefore con-
clude that even when the two solutions on either side of the
membrane are isotonic, there may be a movement of fluid
from one side to the other with a performance of work in
the process.

The experimental proof of the truth of this argument is
to be found in a recent paper by Dr. Lazarus Barlow.
This observer — after pointing out that the huge total
osmotic pressures of the salt solutions in the body can very
seldom come into play — insists on the fact that the most im-
portant point to study in this regard is the initial changes
that take place between dissimilar fluids separated by a
membrane — as he terms it — the initial rate of osmosis. For
this purpose he employs a funnel, the neck of which is pro-
longed into a capillary tube, while on the mouth is tied a
piece of peritoneal membrane. The funnel is filled with
the solution whose osmotic attraction for water it is wished

THE THEORY OF OSMOTIC PRESSURES. 155

to measure, and its mouth covered with the membrane is
immersed in distilled water or in dilute serum.

The experiments which are the most interesting are
those in which decinormal solutions of glucose, urea,
sodium chloride were compared as to their initial rates of
osmosis, the outer fluid being water. He concludes from
his experiments that, in the case of prepared peritoneal
membrane, the initial rates of osmosis of glucose, sodium
chloride and urea in equimolecular solutions do not corre-
spond to the ratio between their final osmotic pressures (as
estimated by the depression of freezing-point), but the
initial rate of osmosis of glucose {i.e., the rate with which
water passes into this solution) is greater than that of
sodium chloride, and the initial rate of osmosis of sodium
chloride greater than that of urea.

In these experiments the only two solutions which
are strictly comparable are those of urea and glucose
(A = 0*189° C), since the decinormal Na CI solution had
nearly double the osmotic pressure of these two (A = 0*35 1).
In three typical experiments, each of which lasted three
hours, the average rates at which the fluid in the funnel
increased in volume during the first hour were : in the case
of glucose, 7! mm. in five minutes ; in the case of sodium
chloride, 43 mm. ; and in the case of urea, iJT mm.
These figures are evidently not proportional to the differ-
ence of osmotic pressures between the fluid and the funnel
and the water in the reservoir. But we have already seen
that the moving force is not the total difference of pressure
between the fluids in the vessels on either side of the
membrane, but the difference of pressure between the
layers of fluid in immediate contact with each side of the
membrane. The fall of osmotic pressure across the thick-
ness of the membrane varies inversely as the rate of
diffusion of the dissolved substance. The question arises
therefore whether the results obtained by Lazarus Barlow
can be accounted for by differences in the rate of diffusion.
In the carefully worked-out tables by this observer we have
all the data necessary to decide the question. In the case
of glucose, the freezing-point of the solution at the begin-

156 SCIENCE PROGRESS.

ning of the experiment was - o'i8q° ; at the end of the three
hours' experiment it was — ot JJ° C. — corresponding to a
loss of 6 per cent, of the dextrose. In the case of the
urea, the freezing-point at the beginning was "189°, and at
the end was- 0*154° C, a loss of 18 per cent. Here then
the initial rate of osmosis of the glucose was about five
times that of the urea ; the loss by diffusion of the glucose
was about one-third that of the urea. In the case of the
sodium chloride the loss amounted to 22 per cent. ; but
here the total difference of osmotic pressure was very
nearly double that of the other two solutions, and the result
is that the initial rate of osmosis of the sodium chloride takes
an intermediate place between that of urea and that of
glucose.

In this paper the results of another experiment are
given to show that osmosis may occur from a fluid having
a higher final osmotic pressure towards a fluid having a
lower final osmotic pressure. If, for example, equimolecu-
lar solutions of sodium chloride and glucose be separated
by a peritoneal membrane, the osmotic flow will take place
from the fluid having the higher final osmotic pressure —
sodium chloride. We might compare with this experiment
the results of separating hydrogen at one atmosphere's
pressure from oxygen at two atmospheres' pressure by
means of a plate of graphite. In this case the initial result
will be a still further increase of pressure on the oxygen
side of the diaphragm — a movement of gas against pres-
sure taking place in consequence of the greater diffusion
velocity of hydrogen.

So far we have only considered the behaviour of solu-
tions when separated by a membrane, the permeability of
which to salts is comparable to that of water ; so that the
passage of salts through the membrane depends merely on
the diffusion rates of the salts. There can be no doubt,
however, that we might get analogous movements of fluid
against total osmotic pressure determined, not by the
diffusibility of the salts, but by the permeability of the mem-
brane for the salts — a permeability which may depend on a
state of solution or attraction existing between membrane

THE THEORY OF OSMOTIC PRESSURES. 157

and salts. We have a familiar analogue to such a condition
of things in the passage of gases through an india-rubber
sheet. If two bottles, one containing carbonic acid, the
other hydrogen, be separated by a sheet of india-rubber,
C03 passes into the hydrogen bottle more quickly than
hydrogen can pass out into the C02 bottle, so that a dif-
ference of pressure is created between the two bottles, and
the rubber bulges into the C02 bottle. We might, in the
same way, conceive of a membrane which permitted the
passage of dextrose more easily than that of urea. With
such a membrane, experiments conducted in the same way
as Dr. Barlow's, would lead to diametrically opposite re-
sults. The importance of the membrane in determining
the direction of the osmotic passage of fluid is well illustrated
by Raoult's experiments. When alcohol and ether were
separated by an animal membrane, alcohol passed into the
ether, whereas if vulcanite were employed for the dia-
phragm, the osmotic flow was in the reverse direction,
and an enormous pressure was set up on the alcohol side of
the diaphragm.

Here we have a possible clue to the "explanation" of
many phenomena of cell activity, to which the term " vital"
is often assigned. In the swimming-bladder of fishes, for
instance, we find a gas which is extremely rich in oxygen,
and the oxygen is said to have been secreted by the cells
lining the bladder. It is, however, very possible that the
processes here may be exactly analogous to Graham's
atmolysis, and that the bladder may represent a perfected
form of Graham's india-rubber bag.

The next point to be considered is the passage of a
dissolved substance across membranes in consequence of
differences in the partial pressure of the substance in ques-
tion on the two sides of the membrane. Great stress is
laid by Heidenhain and his pupil Orlow on the fact that
in the peritoneal cavity, as well as from the intestine, salt
may be taken up from fluids containing a smaller percentage
of this substance than does the blood plasma, and they
regard this absorption as pointing indubitably to an active
intervention of living cells in the process. This argument

158

SCIENCE PROGRESS.

requires examination. Supposing the two vessels A and B
to be separated by a membrane which offers free passage
to water, and a difficult passage to salts. Let A contain '5

n

A

B

per cent, salt solution and B a solution isotonic with a 1
per cent. Na CI, but containing only '65 per cent, of this
salt, the rest of its osmotic tension being due to other dis-
solved substances. If the membrane were absolutely " semi-
permeable," water would pass from A to B until the two
fluids were isotonic, i.e., until A contained 1 per cent. Na CI
(we may regard volume of B as infinitely great to
simplify the argument). If, however, the membrane per-
mitted passage of salt, the course of events might be as
follows : At first water would pass out of A, and salt would
diffuse in until the percentage of Na CI in A was equal
to that in B. There would now be an equal partial pres-
sure of Na CI on the two sides of the membrane, but the
total osmotic pressure of B would still be higher than A.
Water would therefore still continue to pass from A to B
more rapidly than the other ingredients of B could pass
into A. As soon, however, as more water passed only
from A, the percentage of N a CI in A would be raised
above that in B. The extent to which this occurs will
depend on the impermeability of the membrane. As soon,
however, as the Na CI in A reaches a certain concentration
it will pass over into B, and this will goon until equilibrium
is established between A and B. Extending this argument
to the conditions obtaining in the living body, we may con-
clude that neither the raising of the percentage of a salt
in any fluid above that of the same salt in the plasma, nor
the passage of a salt from a hypotonic fluid into the blood
plasma, can afford in itself any proof of an active interven-
tion of cells in the process.

THE THEORY OF OSMOTIC PRESSURES. 159

Thus in the case of the pleura we seem to have a mem-
brane which is very imperfectly semi-permeable. It is per-
meable to salts, but presents rather more resistance to their
passage than to the passage of water. Hence on injecting
•5 per cent. Na CI solution into the pleural cavity water
passes from the pleural fluid into the blood, until the per-
centage of sodium chloride in the fluid is raised perceptibly
above that in the blood plasma. The limit of the resistance
of the pleural membrane to the passage of salt is, however,
soon reached, and then salt passes from pleural fluid into
blood ; but in every case this passage is from a region of
higher to a region of lower partial pressure. Hence at
a certain stage of the experiment we find a higher percentage
of salt in the pleura than in the blood-vessels, although
the total amount of salt in the pleural fluid is less than
that originally put in, or, in other words, salt has been
absorbed.

We have already seen that the effective osmotic pressure
of a substance, i.e., its power of attracting water across a
membrane, varies inversely as its diffusibility, or as the
permeability of the membrane to it. What then will be
the effect supposing that on one side of the membrane we
place some substance in solution to which the membrane
is impermeable ?

We will suppose that A and B both contain 1 per cent.
Na CI, but that B contains in addition some substance x to
which the membrane is impermeable. Since the osmotic
pressure of B is higher, by the partial pressure of x, than
that of A, fluid will pass from A to B by osmosis. But the
consequence of this passage of water will be to concentrate
the Na CI in A, so that the partial pressure of this salt in
A is greater than in B. Na CI will therefore diffuse from
A to B with the result that the former difference of total
osmotic pressure will be re-established. Hence there will
be a continual passage of both water and salt from A to B,
until B has absorbed the whole of A. This result will
be only delayed if the osmotic pressure of A is at first
higher than B, in consequence of a greater concentration
of Na CI in A. There may be at first a flow of fluid

160 SCIENCE PROGRESS.

from B to A, but as soon as the Na CI concentration on
the two sides has become the same by diffusion the power
of x to attract water from the other side will make itself
felt, and this attraction will be proportional to the osmotic
pressure of x.

We have an example of such a process in the absorption
of salt solutions from the connective tissues by the blood-
vessels, as well as in the absorption of the normal tissue
lymph. The capillaries of the connective tissues of the
limbs and peripheral parts of the body are almost imperme-
able to proteids. In consequence of this impermeability the
fluid which is transuded from the capillaries under pressure
contains very little proteid, whereas it contains exactly the
same proportion of salts as does the blood plasma. It seems
probable therefore that the proteid left in solution in the
capillaries must exert a certain osmotic attraction on the
salt solution outside the capillaries. It is easy to
measure this attractive force. If blood serum be placed in
a small thistle funnel, on the open end of which is stretched
a layer of membrane soaked in gelatine, and the inverted
funnel be immersed into salt solution which is isotonic or
even hypertonic as compared with the serum, measured by
the freezing-point, within the next two to four days fluid
will pass into the funnel and rise up in its capillary stem to
a considerable height. I have found that the osmotic
pressure of the non-diffusible constituents of blood serum
measured in this way amounts to between 30 mm. and 40 mm.
Hg. Now although this osmotic pressure is so small, it is of an
order of magnitude comparable with that of the hydrostatic
pressure in the capillaries. This fact is of importance in
that, whereas the capillary pressure determines transudation
from the vessels, the effective osmotic pressure of the
serum (proteids ?) determines absorption by the blood-
vessels. Moreover the osmotic attraction of the serum for
the extravascular fluid will be proportional to the force
expended in the production of this extravascular fluid, so
that at any given time there must be a balance be-
tween the hydrostatic pressure in the capillaries and the
production or absorption of fluid from the extravascular

THE THEORY OF OSMOTIC PRESSURES. 161

spaces — a balance which is known to obtain under physio-
logical conditions. If we increase the volume of circulating
fluid we increase intracapillary pressure and the blood
volume tends to diminish in consequence of increased
transudation. If we diminish the capillary pressure by
bleeding the animal, absorption will predominate over exu-
dation, and the volume of circulating fluid will tend to
increase towards its normal amount.

From this cursory study of some of the simplest examples
of transference of fluids and salts across membranes, we
may draw certain conclusions as to the main factors which
are of importance for the process.

These are : (i) The permeability of the membrane to the
dissolved substances. This permeability may be of the
same character as the permeability of water, in which case
the rates of passage of the dissolved substances across the
membrane vary as their diffusibilities, and are therefore
probably some function of their molecular weights. On the
other hand the membrane may exhibit a certain attraction
for, or power of dissolving, some dissolved substances to the
exclusion of others, in which case there will be no relation
between the diffusibilities and rates of passage of the dis-
solved substances.

(2) The osmotic pressure of the solutions. It is evident
that the rules deduced by Heidenhain from the accepted
theory of osmotic pressures, and quoted at the beginning of
this article, are fallacious in consequence of a too narrow con-
sideration of this second factor to the exclusion of the first.
At the same time it must be confessed that our knowledge
of the permeability of different membranes to different
substances, as well as of the factors on which this per-
meability depends, is still in an embryonic condition.
There can be no doubt that a careful exploration of this
field of research would yield results not only interesting
to the physicist, but also of incalculable value to the
physiologist in his investigation of the phenomena of
living things.

11

162 SCIENCE PROGRESS.

BIBLIOGRAPHY.

(i) Heidenhain. Neue Versuche liber die Aufsaugung im Diinn-
darm. Pfiiigers Archiv, lvi., p. 600, 1894.

(2) LAZARUS BARLOW. Observations upon the Initial Rates of Os-

mosis of certain Substances in Water and in Fluids containing
Albumen. Journ. of Phys., vol. xix., p. 140, 1895.

(3) ORLOW. Einige Versuche iiber die Resorption in der Bauch-

hohle. Pfiiigers Archiv, vol. lix., p. 170, 1894.

(4) Leathes and Starling. On the Absorption of Salt Solutions

from the Pleural Cavities. Journ. of Phys., vol. xviii., 1895.

(5) Leathes. Some Experiments on the Exchange of Fluid be-

tween the Blood and Tissues. Journ. of Phys., vol. xix., p. 1,

1895.

(6) HAMBURGER. Ueber die Regelung der osmotischen Spannkraft

von Fliissigkeiten in Bauch und Pericardialhohle. Du Bois
Archiv, p. 281, 1895.

(7) STARLING. On the Absorption of Isotonic Solutions from the

Connective Tissues. Journ. of Phys., 1896.

Ernest H. Starling.

Science |)ragre$s.

No. 27. May, 1896. Vol. V.

THE PAST, PRESENT AND FUTURE WATER
SUPPLY OF LONDON.1

IN a discourse to the Members of the Royal Institution
on the subject of the Metropolitan Water Supply
nearly thirty years ago, I stated that out of every thousand
people existing upon this planet at that moment, three
lived in London ; and, as the population of London
has in the meantime doubtless grown at a more rapid rate
than that of the rest of the world, it will probably be no
exaggeration to say that now, out of every thousand people
alive on this earth, four live in London ; and therefore any
matter which immediately concerns the health and comfort
of this vast mass of humanity may well merit our most
earnest attention. Amongst such matters that of the
supply, in sufficient quantity, of palatable and wholesome
water is certainly not the least in importance.

It is not therefore surprising that this subject has
received much attention from several Royal Commissions, —
notably from the Royal Commission on Water Supply of
1867, presided over by the Duke of Richmond, the Royal
Commission on the Pollution of Rivers and Domestic
Water Supply of Great Britain, presided over by the late
Sir William Dennison, of which I had the honour to be a
member ; and lastly the Royal Commission, appointed in
1892 to inquire into the Water Supply of the Metropolis,

1 A discourse delivered at the Royal Institution, 21st February, 1896.

12

1 64 SCIENCE PROGRESS.

of which Lord Balfour of Burleigh was Chairman, and of
which Professor Dewar was a member.

The Royal Institution has also for nearly three-quarters
of a century been prominently connected with the investiga-
tion and improvement of the Metropolitan Water Supply ;
no less than four of our Professors of Chemistry having
been successively engaged in this work, viz., Professors
Brande, Odling, Dewar, and myself, whilst three of them
have been members of the Royal Commissions just
mentioned. I may therefore perhaps be excused for
accepting the invitation of our Secretary to bring the
subject under your notice for the third time.

On the present occasion I propose to consider it from
three points of view, viz., the past, the present and the
future ; and, for reasons which will appear hereafter, I shall
divide the past from the present at, or about, the year 1883,
and will not go back farther than the year 1828, when Dr.
Brande, Professor of Chemistry in the Royal Institution ;
Mr. Telford, the celebrated engineer ; and Dr. Roget,
Secretary of the Royal Society were appointed a Royal
Commission to inquire into the quality and salubrity of the
water supplied to the Metropolis.

The Commissioners made careful examinations and
analyses, and reported as follows : " We are of opinion that
the present state of the supply of water to the Metropolis
is susceptible of, and requires, improvement ; that many of
the complaints respecting the quality of the water are well
founded, and that it ought to be derived from other sources
than those now resorted to, and guarded by such restrict-
tions as shall at all times ensure its cleanliness and purity.
(At this time the water was pumped from the Thames
between London Bridge and Battersea.) To obtain an
effective supply of clear water free from insects and all
suspended matter, we have taken into consideration various
plans of filtering the river water through beds of sand and
other materials ; and considering this, on many accounts, as a
very important object, we are glad to find that it is perfectly
possible to filter the whole supply, and this within such
limits, in point of expense, as that no serious objection can

THE WATER SUPPLY OF LONDON. 165

be urged against the plan on[ that score ; and with such
rapidity as not to interfere with the regularity of service."

Before the year i82g, therefore, the river water supplied
to London was not filtered at all ; but after the issue of
this report, the Companies set themselves earnestly to work
to improve the quality of the water by filtration.

The first filter, on a working scale, was constructed and
brought into use by the Chelsea Water Company in the
year 1829. But even as late as 1850 only three out of the
seven principal companies filtered the river water which
they delivered in London ; and it was not until 1856 that
filtration was made compulsory by Act of Parliament,
whilst it can scarcely be doubted that, between this date and
the year 1868, when my observations on turbidity were first
commenced, the operation was very imperfectly performed.

In the year 1832, and again in 1849, London was
severely visited by epidemic cholera, and the agency of
drinking water in spreading the disease forced itself upon
the attention of the observant portion of the medical pro-
fession. It was Dr. Snowe, however, who in August,
1849, first formally enunciated the doctrine that drinking
water polluted by choleraic matters is the chief mode by
which cholera is propagated.

Received at first with incredulity, this doctrine was
supported by numerous facts, and it soon caused renewed
attention to be directed to the quality of the water then
being supplied to the Metropolis ; with the result that the
intakes of the various Companies drawing from rivers
were, one after another, removed to positions above the
reach of tidal influence ; the Thames water being with-
drawn from the river above Teddington Lock, and the Lea
water at Ponder's End, above the tidal reaches of that river.

In every visitation of Asiatic cholera to London, the
water supply was either altogether unfiltered or imperfectly
filtered, besides being derived from highly polluted parts
of the Thames and Lea ; and the enormous loss of life,
amounting in the aggregate to nearly 36,000 people, can
only be attributed to this cause. It has been abundantly
proved that efficient filtration is a perfect safeguard against

1 66 SCIENCE PROGRESS.

the propagation of the disease, and since the year 1854 no
case of Asiatic cholera in London has been traced to the
use of filtered river water.

These are the results arrived at by the most general
investigation of the subject. They show that in every
epidemic, the mortality varied directly with the intensity of
the drainage pollution of the water drunk by the people ;
but if time permitted, a more detailed study of the
statistics in both epidemics would demonstrate, much more
conclusively, this connection between cholera mortality and
the pollution of drinking water — a connection which has quite
recently been terribly emphasised in the case of Hamburg.

Such is the verdict with regard to cholera, and the
same is true of that other great water-borne disease typhoid
fever. But, unlike cholera, this disease is disseminated in
several other ways, and its presence or absence in any
locality may not, of necessity, have any connection with
drinking water, as is strikingly shown by the health
statistics of Manchester.

There is no evidence whatever that, since the year
1869, when typhoid fever appeared for the first time as a
separate disease in the Registrar General's reports, it has
been conveyed by the water supply of the Metropolis.
An inspection of the diagram (No. 1) shows, it is true, a
greater proportional mortality during the period of imperfect
filtration than during the later period ; that is to say from
1883 when the process began to be performed with uniform
efficiency ; but the plotting of a similar curve for the deaths
by typhoid in Manchester shows that this disease arises from
other causes than polluted water, since the water supply
of Manchester, derived as it is from mountain sources, is
above all suspicion of this kind. These other causes have
during the last ten years been much mitigated in London
by various sanitary improvements ; whilst, as shown in
the diagram, there has been no corresponding mitigation
in Manchester.

Although very soon after the year 1856 all the water
supplied to the Metropolis was obtained from sources much
less exposed to drainage pollution, it was still very carelessly

THE WATER SUPPLY OF LONDON.

167

filtered. Previous to the year 1868, there are no records
of the efficiency, or otherwise, of the filtration of the
Metropolitan water supply derived from rivers, as dis-
tinguished from deep wells, the water of which is perfectly
clear without filtration.

It was in the year 1868 that I first began to examine
the water supplied to the Metropolis from rivers with
reference to efficiency of filtration. I n that year, out of
eighty-four samples examined, seven were very turbid,
eight turbid, and ten slightly turbid, so that altogether no
less than nearly 30 per cent, of the samples were those of
inefficiently filtered water. The Metropolitan Water Supply
then, up to the year 1868, may be shortly described as

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derived for many years from very impure sources with
either no filtration at all, or with very inefficient filtration ;
and afterwards, when the very impure sources were
abandoned, the supply was still often delivered in a very
inefficiently filtered condition. But, after the establishment of
monthly reports on the filtration of the river-derived supplies,
the quality of these waters gradually improved in this most
important respect, as is seen from diagram No. 1. In this
diagram, the continuous line with dots represents the
mortality from typhoid in Manchester, the broken and
eroped line the contemporaneous mortality in London, and
the dotted curve the degree of turbidity of the London
water supply.

1 68 SCIENCE PROGRESS.

These observations graphically represented in the dia-
gram show that, at the time they were commenced, the
filtering operations were carried on with considerable care-
lessness, and that this continued, though to a less extent,
down to the year 1883, since which time, and especially
since 1884, the efficiency of filtration of all the river waters
supplied to the Metropolis has left little to be desired.

What is it then that separates the past from the present
water supply of London ? In the first place there is the
change of source — I mean the change in position of the
intakes of the several Companies drawing from the Thames
and Lea — and the total abandonment of the much-polluted
river Ravensbourne by the Kent Water Company. So
long as the water supply was derived from the tidal reaches
of the Thames and Lea, receiving as these reaches did the
drainage of immense populations, the risk of infection from
water-borne pathogenic organisms could scarcely be other-
wise than imminent ; for, although we now know efficient
filtration to be a perfect safeguard, anything short of effi-
ciency must be attended with risk in the presence of such
extreme pollution.

Nevertheless, the line of demarcation between the past
and the present water supply of the Metropolis is, in my
opinion, to be drawn, not when the intakes of the river
companies were removed to positions beyond the possibility
of pollution by the drainage of London, but it must be drawn
at the time when efficient filtration was finally secured and
ever since maintained, that is to say, in the year 1884.

The removal of turbidity by sand filtration, however,
refers only to suspended matters ; but there are sometimes
objectionable substances in solution of which organic matter
is the most important. River water and mountain water,
even when efficiently filtrated, contains more organic matter
than spring or deep well water; but this is reduced in quantity
by storage and especially by filtration, although these waters
can perhaps never be brought up to the standard of organic
purity of spring and deep well water.

THE WATER SUPPLY OF LONDON.

169

THE PRESENT WATER SUPPLY.

At present London is supplied with water from four
sources — the Thames, the Lea, the New River, and deep
wells. Of these the deep wells yield as a rule the purest
water, requiring no filtration or treatment of any kind before
delivery for domestic use. The river waters, on the other
hand, require some kind of treatment before delivery —
storage, subsidence in reservoirs, and filtration. The water
from the Thames is abstracted at and beyond Hampton, far
above the reach of the tide and London drainage. The
water from the Lea is taken out at two points, viz., at Angel
Road near Chingford, by the East London Water Company,

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and above Hertford by the New River Company, who
convey it to Green Lanes by an open conduit twenty-five
miles long, called the New River Cut, in which it is mixed
with a considerable volume of spring and deep well water.

All three river waters are affected by floods and are, as
raw materials, of considerably different quality as regards
organic purity (see diagram No. 2). From these raw
materials by far the largest volume of the Metropolitan
Water Supply is derived, and the chemical or organic
purity of the water sent out to consumers stands in direct
relation to the organic purity of the raw material used, as

170

SCIENCE PROGRESS.

is seen from the diagrams Nos. 3, 4 and 5, which show the
proportional amounts of organic elements in the raw and
filtered waters ; they also show the advantage of storage
in excluding flood water, No. 4 shows that floods in March

PROPORTIONAL AMOUNT OF CRCANIC ELEMENTS
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arid August were circumvented, but not in November. The
numbers in the margins of the diagrams express the pro-
portional amount of organic elements, that in the Kent

PROPORTIONAL AMOUNT OF ORGANIC ELEMENTS
IN RAW LEA AND EAST LONDON COMPANY'S WATER

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Company's water during the nine years ending December

1876 being taken as unity, as is depicted in diagram No. 5.

Hitherto I have spoken of chemical purity or comparative

freedom from organic matter only, but the spread of diseases

THE WATER SUPPLY OF LONDON.

171

such as cholera and typhoid fever through the agency of
drinking water has no connection whatever with the chemical
or organic purity of the water. These diseases are propa-
gated by living organisms of extreme minuteness, to which
the names bacilli, bacteria, and microbes have been given,
and here comes the important question how, if at all, does
filtration secure immunity from these water-borne diseases ?
To Dr. Koch of Berlin, we are indebted for the answer
to this question. By his discovery of a means of isolating
and counting the number of bacteria, or bacilli, or microbes
and their spores in a given volume of water, we were, for
the first time, put into possession of a method by which the
condition of water as regards these living organisms, before

PROPORTIONAL AMOUNT OF ORGANIC ELEMENTS
IN NEW RIVER AND DEEP-WELL WATERS.

1835

so

No. 5.

and after filtration, can be determined with quantitative
exactness. The enormous importance of this invention
(which was first made known and practised in England in
1882 by the late Dr. Angus Smith) is evident, when it is
borne in mind that the living organisms, harmful or harm-
less, contained in water are of such extreme minuteness as
practically to defy detection by ordinary microscopical
examination. But although the microscope cannot detect
with certainty single bacteria or their spores, even the
naked eye can easily discern towns or colonies consisting of
thousands or even millions of such inhabitants.

Dr. Koch's method accomplishes at once two things :
it isolates, in the first place, each individual microbe or

172 SCIENCE PROGRESS.

germ ; and, secondly, places it in conditions favourable for
its multiplication which takes place with such amazing
rapidity that, even in a few hours, or at most in two or
three days, each organism will have created around itself
a visible colony of innumerable members — a town in fact
comparable to London itself for population.

By operating upon a known volume of water, such as
a cubic centimetre for instance, the number of separate
organisms or their spores, in a given volume of the water
under investigation can thus be determined. The following
is the method now adopted in carrying out Koch's process
for the bacterial investigation of drinking water : —

i. Preparation of the nutritive medium.

2. Sterilisation of the medium.

3. Collection of the sample of water in a vacuous tube

afterwards to be hermetically sealed.

4. Transport of the sample to the bacteriological

laboratory, packed in ice to prevent multiplica-
tion.

5. Mixture of a known volume of the water sample

with the nutrient medium.

6. Casting of the mixture into a solid plate.

7. Incubation of the solid plate.

8. Counting of the colonies.

9. Examination of separate colonies, or rather of the

individual members under the microscope.

Sometimes the cultivations are made upon a plate of
the substance called agar which resembles isinglass, and
bears a temperature of blood heat without melting.

In order to ascertain the effect of filtration upon the
bacterial quality of water, it is absolutely necessary that
the sample should be taken immediately after it has passed
through the filters ; for, if it be obtained from the delivery
mains in town, that is to say, after the water has passed
through many miles of pipes, the rapid multiplication of
these organisms, except in very cold weather is such, that
a water which contains only a single living organism per
cubic centimetre, as it issues from the filter, may contain

THE WATER SUPPLY OF LONDON.

173

100 or 1000 in the same volume when, after several hours,
it arrives on the consumer's premises.

Now what is the effect of sand filtration as carried out
by the various Water Companies supplying London upon
the living matter contained in the raw river water ? // is
simply astounding : water containing thousands of bacteria
per cubic centimetre, for a single drop of Thames water
sometimes contains nearly 3000 separate living organisms,
comes out from the sand filters with fifty, thirty, ten, or even
less of these organisms per cubic centimetre, or the number
of microbes in a single drop is reduced to two or even to zero.

MICROBES IN RAW AND FILTERED THAMES
WATER 1894.

JANUARY

FEBRUARY MARCH APRIL

MAY JUNE

JULY AUCUST SEPTEMBER

OCTOBER

NOVEMBER DECEMBER

No. 6.

MEAN

Rather less than one-tenth of the total volume of water
supplied to London is derived by the Kent Water Company
from deep wells in the chalk. As it issues from the porous
rock into the fissures and headings of these wells, this water
is, in all probability, absolutely sterile ; but by the time it
has been pumped up to the surface it usually contains a
certain number, though small, of microbes. Thus, during
the year 1892 it contained on the average six per cubic
centimetre in 1893, thirteen; in 1894, fifteen; and in
1895, eight.

The diagram No. 6 shows graphically the bacterial
improvement of the Thames water by filtration during

i74 SCIENCE PROGRESS.

the year 1894. ^n this diagram the black squares represent
the number of microbes in a given volume of the raw water
in each month, and the white centres the number remaining
in the same volume after filtration.

Although deep well water has, from a bacterial point
of view, a decided advantage, the filtered river waters
are not very far behind, and there is every reason to believe
that with the improvements which are now being carried out
by the various river Water Companies, the Kent Company's
deep well water will, before long, be run very hard by the
other supplies.

By the examination of the water as it issues from the
filters, the utmost freedom from microbes, or maximum
degree of sterility of each sample is determined. This
utmost freedom from bacterial life after all sources of con-
tamination have been passed is obviously the most
important moment in the history of the water ; for the
smaller the number of microbes found in a given volume at
that moment the less is the probability of pathogenic or
harmful organisms being present ; and although the non-
pathogenic may afterwards multiply indefinitely this is of
no consequence in the primary absence of the pathogenic ;
but it is only fair, in describing the character of the present
water supply of London, to say that not a single pathogenic
organism has ever been discovered even in the ^filtered
water as it enters the intakes of the various Companies,
although these organisms have been carefully sought for.
It is sometimes said that the non-pathogenic organisms
found in water may be beneficial to man ; but this idea is
not borne out by the fact of their entire absence from the
food which nature provides for young animals. Healthy
milk is absolutely sterile.

As it is at present impracticable to obtain water, uni-
formly at least, free from microbes, it is desirable to adopt
some standard of bacterial purity ; and 100 microbes per
cubic centimetre has been fixed upon by Dr. Koch and
myself as the maximum number allowable in potable water.
This standard is very rarely infringed by the London
Water Companies, whilst I have every reason to hope that,

THE WATER SUPPLY OF LONDON. 175

in the near future, now that special attention is directed to
bacterial filtration, it will not be approached within 50 per
cent. This hope is based not only upon my own observations,
but also upon the exhaustive and exceedingly important
investigations carried out at the Lawrence Experiment
Station by the State Board of Health of Massachussetts,
under the direction of Mr. George W. Fuller, the official
biologist to the Board.

More than six years have already been spent in the prose-
cution of these American experiments, and many thousands
of samples of water have been submitted to bacterial cultiva-
tion. The Massachussetts experimental filters are worked at
rates up to 3,000,000 gallons per acre daily, which renders
the results available for application to public water supplies ;
indeed none of the water delivered in London is filtered at
so rapid a rate as this. It was found that at these rates all
the disease-producing germs, which were intentionally and
in large numbers added to the unfiltered water, were
substantially removed. The filters were so constructed
and arranged as to allow direct comparison of the bacterial
purification of water under different rates of filtration, with
sand of different degrees of fineness, with different depths
of the same sand, and with intermittent and continuous
filtration.

The actual efficiency of these filters was also tested by
the application of the bacillus of typhoid fever. Very large
numbers of these bacilli and of other species were applied
in single doses to the several filters at different times, and
the effluent was examined four times daily for several days
afterwards. The results so obtained give a thoroughly
trustworthy test of the degree of bacterial purification
effected by each of the experimental filters, and these are
the data which have been largely used by the Mas-
sachussetts State Board of Health in deducing the rules
which they consider ought to be observed in water filtration.

Among the subjects investigated by means of these
experimental filters were : —

1. The effect, upon bacterial purification, of the rate of
filtration.

176 SCIENCE PROGRESS.

2. The effect of size of sand grains upon bacterial

purification.

3. The effect of depth of material upon bacterial

purification.

4. The effect of scraping the filters upon bacterial

purification.
Time does not permit of my giving the answers to these
questions in detail ; but they may be summarised as follows : —

1. The rate of filtration between 500,000 and 3,000,000
gallons per acre per day exercises practically no effect on
the bacterial purity of the filtered water. It is worthy of
note that the rates of filtration practised by the several
Water Companies drawing their supplies from the Thames
and Lea are as follows: Chelsea Company, 1,830,000;
West Middlesex, 1,359,072 ; Southwark Company, 1,568, 160;
Grand Junction Company, 1,986,336; Lambeth Company,
1,477,688; New River Company, 1,881,792; and East
London Company, 1,393,920. Hence not one of the
London Companies filters at the rate of 2,000,000 gallons
per acre per day ; at which rate in the Massachussett's
filters 99*9 per cent, of the microbes present in the raw
water were removed.

2. The effect of size of sand grains was found to be very
considerable ; and, in confirmation, I find that by the use of
a finer sand than that employed by the Chelsea Company,
the West Middlesex Company is able, with much less stor-
age, to attain an equal degree of bacterial efficiency.

3. The depth of sand, between the limits of one and five
feet, exercises no practical effect on bacterial purity when
the rate of filtration is kept within the limits just specified.
And this result is quite borne out by my own experience
gained in the bacterioscopic examination of the filtered
waters of the seven Companies supplying the Metropolis
from rivers. Thus the New River Company, with i*8 feet
of sand on the filters, compares favourably with the Chelsea
Company, the sand on whose filters is more than twice that
depth.

Placed in the order of thickness of sand on their filters,
the Metropolitan Companies range as follows : Chelsea,

THE WATER SUPPLY OF LONDON. 177

Lambeth, West Middlesex, Southwark, East London,
Grand Junction, and New River. Placed in the order of
efficient filtration they range as follows : Chelsea and West
Middlesex equal, New River, Lambeth, East London,
Southwark, and Grand Junction.

4. When there is such an accumulation of deposit on
the surface of a sand filter that, for practical purposes,
sufficient water cannot be made to pass through it, the
surface of the filter has to be scraped ; that is to say, the
mud and about half an inch of the sand are removed from
the surface. After this operation, there is sometimes an
increase in the number of bacteria in the filtered water, and
it was noticed that the increase was greater in shallow than
in deep filters and with high than with low rates of filtration;
and there is no doubt that the effect of scraping is con-
siderably magnified when coarser descriptions of sand are
employed, as in the case of the filters of the London Water
Companies. I should like, therefore, to impress upon the
engineers of these Companies the desirability of using finer
sands than are at present employed.

INFLUENCE OF THE BACTERIAL CONDITION OF THE RAW
RIVER WATER UPON THAT OF THE FILTERED EF-
FLUENT.

I have found that the number of bacteria in a given
volume of filtered water is to a considerable extent in-
fluenced by the number contained in the raw water supplying
the filter ; and from this point of view, therefore, the bacterial
condition of the raw river water used in the Metropolis is of
no inconsiderable importance.

Since May, 1892, I have made monthly determina-
tions of the number of microbes capable of developing
on a gelatine plate in a given volume of raw Thames water
collected at the intakes of the Metropolitan Water Companies
at Hampton ; and the number has varied during this time
between 631 and 56,630 per cubic centimetre, the highest
numbers having, as a rule, been found in winter or when

178

SCIENCE PROGRESS.

the temperature of the water was low, and the lowest
in summer or when the temperature was high.

Now, besides temperature, there are two other conditions
to either of which this difference may be attributed, viz.y
sunshine and rainfall, and I have endeavoured by a series
of graphic representations to disentangle these possible
influences from each other by placing the results of the
microbe determinations in juxtaposition with (i) the tem-
perature of the water at the time the samples were taken ;

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(2) the number of hours of sunshine on the day and up to
the hour when each sample was drawn and on the two
preceding days, and (3) the flow of the Thames over
Teddington Weir on the same day expressed in millions
of gallons per twenty-four hours. Although the graphic
representations were confined to the Thames, the conditions
affecting bacterial life in this river are doubtless equally
potent in other rivers and streams.

The samples for microbe cultivation were collected at

THE WATER SUPPLY OF LONDON.

179

about nine inches below the surface of the water in partially
exhausted and sealed tubes, the ends of which, when the
tubes were lowered to the required depth, were broken off
by an ingenious contrivance devised by my Assistant, Mr.
Burgess. On being withdrawn from the river the tubes
were immediately hermetically sealed and packed in ice for
conveyance to my laboratory, where the cultivation was
always commenced within four hours of the time of collection.

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No. 8.

For the records of sunshine, I am indebted to the
kindness of Mr. James B. Jordan of Staines ; and for
gaugings of the Thames at Teddington Weir to Mr. C. J.
More, the engineer to the Thames Conservancy Board.

The graphic representation of these collateral observa-
tions affords definite evidence as to which of the three
conditions — temperature, sunshine, and Mow of the river —
has the predominant influence upon bacterial life in the
water. The first diagram (No. 7) compares the number of

13

i8o

SCIENCE PROGRESS.

microbes per cubic centimetre with the temperature at the
time the sample was taken. The horizontal lines express
the numbers of microbes and the temperature, while the
vertical lines denote the months when the samples were
taken. For obvious reasons the horizontal lines express-
ing the numbers of microbes and temperatures are num-
bered in opposite directions.

The diagram shows that although coincidences between
a high number of microbes and a low temperature are not

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wanting, some other condition entirely masks the effect, if
any, of temperature.

The next diagram (No. 8) institutes the comparison
between the number of microbes and the hours of sun-
shine to which the water has been exposed. The diagram
is constructed on the same lines as the first.

It is here seen that, as in the case of temperature,
there is some other condition which entirely overbears the
influence of sunlight in the destruction of microbes in the

THE WATER SUPPLY OF LONDON. 181

river water. This condition is the amount of rainfall higher
up the river, or, in other words, the volume of water flowing
along the river bed, as is seen from the comparison repre-
sented in the next diagram (No. 9).

This diagram shows very conclusively that the volume
of water flowing in the Thames is the paramount influence
determining the number of microbes. It compares the
volume of water in the river gauged at Teddington Weir
with the number of microbes found in the raw Thames
water at Hampton on the same day. In this diagram, the
numbers representing the flow of the river in millions of
gallons per day and the number of microbes per cubic
centimetre in the water both run from the bottom of the
diagram upwards.

Comparing the curves in the diagram it is seen that,
with very few exceptions, a remarkably close relation is
maintained between them.

The only exception of any importance to the rule that
the number of microbes varies directly with the flow of
the river, occurring during the thirty-two months through
which these observations were continued, happened in
November, 1892, when the flow increased from 501 mil-
lions of gallons in October to 1845 millions in November,
whilst the microbes actually diminished in number from
2216 to 1868 per cubic centimetre. Neither the sunshine
nor the temperature records of these two months, however,
afford any explanation of this anomalous result, for there
was a good deal of sunshine in October before the collection
of the sample and the temperature was higher, whilst in
November no ray of sunshine reached the Thames during
the three days preceding the taking of the sample and the
temperature was nearly 40 C. lower than in the preceding
month. I have ascertained, however, that the Thames
basin had been twice very thoroughly washed out by heavy
floods before the time when the November sample was
taken, and this affords a satisfactory explanation of the
anomalous result yielded by this sample.

These comparisons demonstrate that the number of
microbes in Thames water depends directly upon the rate

182

SCIENCE PROGRESS.

of flow of the river, or, in other words, on the rainfall, and
but slightly, if at all, upon either the presence or absence of
sunshine or a high or low temperature ; and they are con-
firmed by the continuation of these observations during the
year 1895 exhibits in diagram No. 10.

With regard to the effect of sunshine upon bacterial
life, the interesting observations of Dr. Marshall Ward
leave no doubt that sunlight is a powerful germicide ; still
it is obvious that its potency in this respect must be greatly
diminished, if not entirely annulled, when the solar rays
have passed through a stratum of water of even com-

MICROBES and FLOW of THAMES

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No. 10.

paratively small thickness before they reach the living
organisms. By a series of ingeniously contrived experi-
ments, Mr. Burgess has demonstrated the correctness of
this view.

A sterile bottle about half filled with Thames water was
violently agitated for five minutes to insure equal distribu-
tion of the organisms. Immediately afterwards a number
of sterile glass tubes were partially filled with this water
and sealed hermetically. Three of these tubes were
immediately packed in ice, and the remainder were attached
in duplicate at definite distances apart to a light wire frame
which was then suspended vertically in the river. The

THE WATER SUPPLY OF LONDON. 183

experiments were made near the Grand Junction Company's
Intake at a place favourable for the sun's rays to fall on the
river without any obstruction.

The river was at the time in a very clear condition and
contained but little suspended matter ; whilst the day was
fine, although clouds obscured the sun occasionally. The
tubes were exposed to light in the river for four and a half
hours — from ICV30 a.m. to 3 r.M. on 15th May, 1895. At
the end of this time the tubes were packed in ice for trans-
port to my laboratory, where the cultivation was started
immediately. The colonies were counted on the fourth day
and yielded the results given in the table : —

No. of Colonies
per c.c.
Thames water packed in ice immediately after collection - 2127
Thames water after exposure to sunlight for 4^ hours at

surface of river ------- 1140

Thames water after exposure to sunlight for 4^ hours at

6 in. below surface of river ----- i^o

Thames water after exposure to sunlight for 4^ hours at

1 ft. below surface of river - - - - - 2150
Thames water after exposure to sunlight for 4J hours at

2 ft. below surface of river ----- 2430
Thames water after exposure to sunlight for 4! hours at

3 ft. below surface of river ----- 2440

These experiments show that, on 15th May the
germicidal effect of sunlight on Thames microbes was nil
at depths of one foot and upwards from the surface of the
water. It cannot, therefore, excite surprise, that the effect
of sunshine upon bacterial life in the great mass of Thames
water should be nearly, if not quite, imperceptible. It is
thus ascertained that sunlight can only kill the germs, or
microbes, near the surface of the water, whilst those at any
depth, for the most part, escape destruction.

On the other hand the enormous effect of floods in
augmenting the number of microbes can hardly surprise us,
for when a great body of water has flowed over the banks
of the river, which are at other times dry and exposed, it
carries along with it countless impurities — an effect common
both to the main stream and its tributaries. The Thames

184 SCIENCE PROGRESS.

basin is as it were, on every such occasion, thoroughly-
washed out, and it is only to be expected that the number
of microbes in the water should be enormously increased as
is found to be the case.
Now with respect to

THE WATER SUPPLY OF THE FUTURE.

In view of the rapid increase of the population of Lon-
don, fears have from time to time been entertained that the
water supply from the Thames basin, that is to say from
the rivers Thames and Lea, supplemented by water from
springs and deep wells within the basin itself, would soon
be insufficient in quantity ; whilst the quality of the
water taken from the river has, up to a comparatively
recent date, been considered unsatisfactory. On these
grounds various schemes have, from time to time, been
brought forward for the supply of the Metropolis from
other river basins — from the Wye, the Severn, the river
basins of North Wales, and of the Lake Districts of
Cumberland and Westmoreland.

It is worthy of note, however, that all the Royal Com-
missions have arrived tinanimously at the conclusion
that the quantity of water obtainable from the Thames
basin is so ample as to render the necessity of going else-
where a very remote contingency.

I shall now endeavour to put, very shortly before you
a few facts which, in my opinion, prove that, both as
regards quantity and quality, the Thames basin will for a very
long time to come afford an abundant supply for the Metro-
polis. There is indeed no river basin in Great Britain
which affords such an abundant supply of excellent water
as that available in the Thames basin.

Besides that which flows directly into the rivers, this
water is contained in the Chalk, Oolite, and Lower Green-
sand, which are the best water bearing strata in the
kingdom. From these rocks it issues in copious springs
of unsurpassed organic purity. I have personally inspected
every spring of importance in the Thames basin and have

THE WATER SUPPLY OF LONDON.

185

analysed samples of the water. The results, in a very con-
densed form, are recorded in the annexed Table. Twenty-

SPRING AND DEEP-WELL WATERS IN THE THAMES

BASIN.

Results of Analysis in
Parts per 100,000.

Oolite.

Average of 21

Samples.

Lower

Greensand.

Average of 5

Samples.

Chalk.

Springs.

Average of 8

Samples.

Wells.

Average of 36

Samples.

Total Saline Matters -
Organic Carbon - -
Organic Nitrogen - -
Hardness before boiling

after

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one samples of Oolitic spring- water were analysed, and
every one of these was of even greater organic purity
than the water delivered by the Kent Company, which I
have always regarded as the standard of organic purity to be
aimed at in all other Water Works.

Five springs issuing from the Lower Greensand were
examined ; and again, every one of these was of even
greater purity, organically, than the Kent Company's
water ; whilst they were, on the average, only one-third as
hard. Forty-six samples of water from the Chalk were
chemically examined, and these also contained but the
merest traces of organic matter.

All these samples from the Chalk were derived from
sources where the water-bearing- stratum is free from a
covering of London clay ; but, as soon as the Chalk dips
beneath the London Tertiary Sands and clay, the quality of
the water undergoes a remarkable alteration. The total
solids in solution are greatly increased in amount, whilst
the hardness is much mitigated, owing to the replacement
of bicarbonate of lime by bicarbonate of soda. These
waters are also of high organic purity ; but, as the quantity
is very limited, it is useless to dwell upon them. They

186 SCIENCE PROGRESS.

supply the Trafalgar Square fountains and the London
breweries, and we can well afford to leave them to be con-
verted into beer. For dietetic purposes there is no better
water in the kingdom than the underground water of the
Thames basin. For sentimental reasons I should like to
see it conveyed to the works of the various companies in
special conduits ; but we have seen that, on hygienic
grounds, it may safely be allowed to flow down the bed of
the Thames if it be afterwards efficiently filtered.

So much for quality, now as to quantity ; the basins of
the Thames and Lea include an area of upwards of 5000
square miles. Of this rather more than one half (including
the Oolitic, Cretaceous, and portions of the Tertiary Forma-
tions) is covered by a porous soil upon a permeable water
bearing stratum. The remainder is occupied by the
Oxford, Kimmeridge, Gault, and London Clays ; being
thus covered by a clay soil upon a stiff and impervious
subsoil.

The annual rainfall of the district is estimated at an
average of twenty-eight inches. The rivulets and streams
of the Thames basin are formed and pursue their course on
clay land. There are no streams on the Chalk. That
which falls upon this porous stratum and does not evaporate
sinks, mostly where it alights, and heaps itself up in the
water-bearing stratum below, until the latter can hold no
more. The water then escapes as springs at the lowest
available points.

Innumerable examples of these springs occur all round
the edge of the Thames basin, and at various points within
it. Thus from the Chalk they are ejected at the lip of the
Gault ; and in the Oolitic area by the Fuller's Earth below
it, or by the Oxford Clay, geologically, above it.

According to the guagings of the engineer of the
Thames Conservancy Board there passed over Teddington
Weir, in 1892, 387,000 millions of gallons, equal to an
average flow of 1060 millions of gallons daily. In the
following year, 1893, their passed over Teddington Weir
an aggregate of 324,227 millions of gallons, or a daily
average of 888 millions, the average for the two years being

THE WATER SUPPLY OF LONDON. 187

974 millions of gallons, and this number does not in-
clude the 1 20 millions daily abstracted by the five London
Water Companies who draw their supplies from the
Thames.

Thus, in round numbers, we may say that after the
present wants of London have been supplied from this
river, there is a daily average of nearly 1000 millions of
gallons to spare. Surely it is not too violent an assumption
to make that the enterprising engineers of this country can
find the means of abstracting and storing for the necessary
time one-fourth of this volume.

As regards the quality of this stored water, all my
examinations, of the effect of storage upon the chemical and
especially upon the bacterial quality, point to the conclusion
that it would be excellent. Indeed the bacterial improve-
ment of river water by storage for even a few days is
beyond all expectation. Thus the storage of Thames water
by the Chelsea Company for only thirteen days reduces
the number of microbes to one-fifth the original amount,
and the storage of the river Lea water for fifteen days,
by the East London Company, reduces the number on the
average from 9240 to i860 per cubic centimetre or to one-
fifth ; and lastly, the water of the New River Cut, con-
taining on the average 4270 microbes per cubic centimetre
contains, after storage for less than five days, only 18 10,
the reduction here being not so great, partly on account
of the shorter storage, but chiefly because the New River
Cut above the point at which the samples were taken, is
itself a storage reservoir containing many days' supply after
filtration. Indeed quietness in a subsidence reservoir is,
very curiously, far more fatal to bacterial life than the most
violent agitation in contact with atmospheric air ; for the
microbes which are sent into the river above the falls of
Niagara, by the City of Buffalo, seem to take little or no
harm from that tremendous leap and turmoil of waters,
whilst they subsequently, very soon, almost entirely dis-
appear in Lake Ontario.

It is not, therefore, too much to expect that storage for,
say a couple of months, would reduce the number of

188 SCIENCE PROGRESS.

microbes in the Thames flood water down to nearly the
minimum ever found in that river in dry weather, whilst,
by avoiding the first rush of each flood, a good chemical
quality could also be secured.

There is, therefore, I think, a fair prospect that the
quantity of water derivable from the Thames at Hampton
could be increased from its present amount (120 millions of
gallons per diem) to 370 millions.

Again, in the river Lea, although here the necessary
data for exact calculations are wanting, it may be assumed
that the present supply of 54 millions of gallons could
be increased by the storage of flood water to 100
millions per day. To these volumes must be added the
amount of deep-well water which is attainable from those
parts of the Thames basin which lie below Teddington Lock,
and in the Lea basin beloiv Lea Bridge, and which was
estimated by the last Royal Commission at rather more
than 67J millions of gallons.

Thus we get the grand total of 53735- millions of
gallons of excellent water obtainable within the Thames
basin, the quality of which can be gradually improved, if it
be considered necessary, by pumping from the water bear-
ing strata above Teddington and Lea Bridge respectively,
instead of taking the total supply from the open rivers
above these points. Such a volume of water would scarcely
be required for the supply of the whole water area of Lon-
don at the end of fifty years from the present time, even
supposing the population to go on increasing at the same
rate as it did in the decade 1881-91, which is an assumption
scarcely likely to be verified.

In conclusion, I have shown that the Thames basin can
furnish an ample supply for fifty or more years to come,
whilst the quality of the spring and deep-well waters and of
the filtered river water would be unimpeachable. To secure
these benefits for the future, storage must be gradually pro-
vided for 1 1,500 millions of gallons of flood water judiciously
selected in the Thames Valley, and a proportionate volume
in the basin of the Lea ; whilst filtration must be carried to
its utmost perfection by the use of finer sand than is at

THE WATER SUPPLY OF LONDON. 189

present employed, and by the maintenance of a uniform rate
during the twenty-four hours.

There is nothing heroic in laying pipes along the banks
of the Thames, or even making reservoirs in the Thames
basin. They do not appeal to the imagination like that
colossal work, the bringing of water to Birmingham from
the mountains of Wales, and there is little in such a scheme
to recommend it to the minds of the enterprising engineers
of to-day. Nevertheless, by means of storage, by utilising
springs, by sinking deep wells, and by such comparatively
simple means, we have, in my opinion, every reason to con-
gratulate ourselves that for half a century at least we have
at our dooi's, so to speak, an ample supply of water which for
palatability, wholesomeness, and general excellence will not
be surpassed by any supply in the world.

E. Frankland.

SOME RECENT MEMOIRS UPON
OLIGOCH^TA.

THE literature relating to this group of worms is
summed up in my Monograph of the Oligochceta
lately issued by the Clarendon Press ; but so energetic are
the unfortunately somewhat few workers in this particular
subject that new facts have gone on accumulating with some
rapidity since the publication of that work. It is my
intention in the present article to offer the reader a re'sume
of this latest work with, naturally, some references to what
has gone before.

It is agreed by all those who are acquainted with the
terrestrial Oligochaeta that their peculiar mode of life, their
susceptibility to sea water, and the comparatively few
chances of dispersal enjoyed by them, render their distribu-
tion highly important in estimating the relations between
land masses now and in the past. This has an especial
bearing upon the theory of the former northward extension
of the Antarctic Continent, a matter upon which much has
been written lately. To deal adequately with this large
question would of course demand more space than can be
allowed me. I shall content myself with referring solely to
the evidence which is forthcoming from the study of earth-
worms. Fortunately we are in possession of a considerable
amount of information about the terrestrial Olioochaeta of
New Zealand and Patagonia ; the former country indeed
must be regarded as being better known perhaps than any
quarter of the globe, excepting of course Europe. The
extensive collections lately made by Dr. Michaelsen in
South America have added largely to the number of species
brought back by his predecessors. It results from an
examination of the species found in the two countries that
in both of them the prevailing types belong to the genera
Acanthodrilus and Microscolex, particularly the former. Of
the thirty-two indigenous species at present known from
Patagonia and the more southern parts of the South Ameri-

SOME RECENT MEMOIRS UPON OLIGOCH/ETA. 191

can Continent, twenty are members of the genus Acantho-
drilus, eleven are Microscolex and one is a PericJiesta. Besides
these are a few obviously imported Lumbricus and
Allolobophora from Europe or North America. I say
obviously imported because these worms are only found in
cultivated ground and near the coast ; as civilisation is left
behind these species decrease and are replaced by the
truly indigenous species. Among the twenty species of
Acanthodrilus are included two or three which occur in the
Falkland Islands and in South Georgia. Turning to New
Zealand we find that out of twenty indigenous species nine
are Acanthodrilus, six belong to the closely allied genera
Octochcehis, Deinodrilus, and Plagiochcsta, three are Micro-
scolex, while the two remaining are a Perichceta and a
Megascolides, two genera which are eminently characteristic
of the adjoining continent of Australia. Between New
Zealand and South America is a long stretch of ocean,
sparsely scattered over which are islands of volcanic origin.
From three of these islands earthworms have been collected.
In Kerguelen and Marion Island is a species of Acantho-
drilus peculiar to those islands, and I have lately received,
and am describing in the forthcoming June number of the
Proceedings of the Zoological Society, a second species of
that genus from Macquarie Island. The significance of
these facts will be more apparent when we consider how
far the genera that have been referred to in the fore-
going are distributed outside of this antarctic area. Micro-
scolex is found in many parts of central and the warmer
western regions of North America ; it has been met with
also in Europe, Algeria and Teneriffe. Acanthodrilus
occurs in Australia where it is represented by three species,
all of which however inhabit the eastern half of the island
continent, that part in fact which is nearest to New
Zealand ; Acanthodrilus has one species in Natal, one in
New Caledonia and two in North America.

We have evidently therefore a fauna of earthworms
peculiar to the antarctic region, into which more northern
forms have been able to make but slight inroads and from
which but few stragglers have wandered.

i92 SCIENCE PROGRESS.

As to other distributional facts and theories, it is
probable that I have underestimated in my Monograph the
distinctness of the Palaearctic and the Nearctic regions of
Mr. Sclater. I was disposed to unite them into one Hol-
arctic as Professor Newton has called it. Further investi-
gations have tended to emphasise the justice of separating
these two regions. This evidence has been mainly collected
by the industry of Dr. Gustav Eisen, of San Francisco ;
but others whose names and memoirs will be found quoted
in the list of literature at the end of this article have added
details of importance. The North American continent is
inhabited by a fair number of peculiar genera, of which
Diplocardia, originally described some years since by
Garman, has four species (partly referred to the undoubtedly
synonymous genus Geodrilus) ; there are also peculiar to
this region Phoenicodrilus, nearly related to the central
and South America Ocuerodrilus, and Sparganophilus ; of
this latter genus the original species was found by
Benham in the Thames ; but as there are half a dozen
American species it seems likely that its occurrence in
England is a case of importation. Bimastos is a genus
perhaps justly separable from Allolobophora, from which it
chiefly differs in the large size (for a Lumbricid) of the
glandular sac in which the efferent male ducts terminate.
Besides these peculiar genera are a few species of the
Central and South American genera Ocuerodrilus and
Kerria, and of the almost world-wide Benhamia. Aleodrilus
is an Acanthodrilid that Eisen is disposed to separate from
Diplocardia ; two species of Acanthodrilus complete the
list of non-European inhabitants of the North American
Continent. But in addition to these are a number of Allolo-
bophora and Lumbricus — the characteristic forms ol the
Palaearctic region — two or three of which are, however, so
far as our present knowledge goes peculiar to North
America. These facts perhaps justify the retention of
the Nearctic region, and they are perhaps also significant
in that the peculiar forms are western in range — a possible
indication of their approaching extirpation by European
species introduced by commerce.

SOME RECENT MEMOIRS UPON OLIGOCHJETA. 193

The original indigenous forms, South American in
character, may be regarded as having been gradually
driven to the west by the encroachment of artificially in-
troduced species. In other respects the geographical regions
indicated by the distribution of earthworms agree fairly well
with the generally received scheme of Mr. Sclater. The
Ethiopian region is peculiarly distinct ; the Neotropical is
also nearly if not quite as plainly marked ; but the Oriental
fades into the Australian, and it is indeed not easy to
separate them at all.

The only other matter affecting the distribution of earth-
worms with which I shall deal here is the question of
oceanic islands. Our information upon the subject is not
however by any means extensive ; the largest collection
made is due to the energy of Mr. Perkins, and has been
described by me in a paper communicated to the Zoological
Society. These worms were gathered in the Sandwich Is-
lands, and belong to a number of species of which only two
(and a doubtful third) have not been found elsewhere ;
these two belong to the genus Perichccta, a genus prevalent
in tropical regions, especially of the old world. That the
bulk of the species known from these and other oceanic
islands are forms which have been in all probability intro-
duced by accidental transference by man is rather what might
be expected from the limited powers of independent travel
possessed by these animals. There is at present no certain
evidence that there are any truly indigenous earthworms in
oceanic islands, with the exception of Kerguelen — a fact
which as I have already hinted may be due to other causes.

To Linnaeus only a single species of earthworm was
known, his Liimbricus terrestris, now believed to have beeii
a compound of more than one species. Grube in his
Familie der Anneliden, published in 1851, reckoned up
only forty-two earthworms, and of these one or two are
now known not to be earthworms at all, and of the re-
mainder many are unrecognisable or synonyms. Since that
period the increase of new forms has gone on — of late
with extreme rapidity ; at the present moment we are
acquainted with rather over 500 distinct and well char-

i94 SCIENCE PROGRESS.

acterised species. And this estimate does not take into
consideration subspecies or well marked varieties, and pays
no attention to " species incertae ". Of aquatic Oligochceta
150 is about the number of known species ; but this
group is decidedly less known than the former. As with
other groups of animals this great increase in the number
of known species has added to our knowledge of anatomical
fact, but rendered harder the formation of classificatory
schemes. No indistinctness, however, has arisen to blur
the perfectly sharp outlines of the group Oligochaeta, no
''intermediate" forms have been discovered whose relega-
tion to the group is a matter of uncertainty or convenience.
At the same time a few approximations in structure to the
leeches on the one hand, and to the Polychseta on the
other have been discovered ; but these are in no case of
first-rate importance. Perhaps the most remarkable is the
description of the gills of the African genus Alma. This
worm was originally described under that name by Grube
in 1855. Thirty-four years later Levinsen, apparently in
ignorance of Grube's paper, named a fragment of what was
obviously the same worm Digitibranckus, and described in
the same paper Siphonogaster, an Annelid characterised by
a pair of long processes an inch or so in length, and of a
spatula-like form arising from the eighteenth segment.
These have been subsequently shown to be processes con-
taining the outer section of the sperm duct which opens
near to the extremity. Michaelsen showed that all these
three worms are identical, and has thus been able to put
beyond question the existence of a true earthworm l with
branched retractile gills on the posterior segments of the
body. It was not by any means clear from the earlier
descriptions that the gilled worm was not a Polychaet.
Among the lower aquatic Oligochsetes there are at least
three gilled forms, apart from Dero which has a circlet
of ciliated processes, with vascular twigs lying round the
anus. These forms are Chcstobranckus of Bourne, and
Branchiura and Hesperodrilus branchiatus of myself. In

1 Structurally ; in habit it is aquatic.

SOME RECENT MEMOIRS UPON OLIGOCHJETA. 195

the two latter (which are allied to Tubifex) are contractile
branchiae, not branched however, on some of the posterior
segments of the body. More numerous are indications of
affinity with the leeches. I may, in the first place, refer
to that group of parasitic Oligochaeta, once placed among
the leeches but now usually allowed to be true Oligochaeta,
for which Vejdovsky has proposed the name of Disco-
drilidae on account of their posterior sucker. An American
genus Bdellodrilus has lately been studied with care by
Moore whose results entirely confirm the placing of the
worms amono- the Oligochaeta and their removal from the
leeches. Their chief points of likeness to the Hirudinea are
(1) absence of setae ; (2) existence of jaws ; (3) presence of a
sucker ; (4) median unpaired character of reproductive pores.
The first and last of these characters are, however,
found in a few undoubted Oligochaeta, for instance, Anachczta,
as its name denotes, has no setae, and besides Mr. Moore
describes large gland cells in Bdellodrilus which may re-
present setigerous cells of Oligochaeta. As to the median
generative pores they are very frequent among Oligochaeta.
The reproductive organs themselves are decidedly upon the
Oligochaetous pattern. The gonads are entirely free from
their ducts, and there is a single spermatheca, a structure
entirely wanting among the true leeches. The male ducts
are two pairs, opening freely by ciliated mouths into the
coelom and uniting into a common terminal atrium. Their
arrangement recalls that of the Lumbriculidae. The ovaries
are proliferations of the coelomic walls and their contents
escape to the exterior by a slit in the body walls lined by
epithelium, a kind of rudimentary oviduct paralleled in the
Enchytraeidae, and in the Eudrilid Nentertodrilus. There
is nothing leech-like about the reproductive organs, except-
ing the terminal penis — a structure, however, which is
also found in many Eudrilids and in some other Oligo-
chaeta. The conclusions of the author that the Disco-
drilidae are Oligochaeta slightly modified for a parasitic
life is quite borne out by their structure. We may admit
at the same time that this modification is in the direction
of the leeches.

14

196 SCIENCE PROGRESS.

In addition to questions of relationship to other neigh-
bouring groups, recent investigation has brought to light
facts of interest in the anatomy of the Oligochaeta which
bear upon the mutual affinities of the families and genera
into which the order is divided. In this direction the main
discoveries of importance relate to the excretory system. In
all the simple aquatic genera each segment of the body
contains a single pair of nephridia ; as a rule these organs
are wanting in the anterior segments, and Professor Bourne
was unable to find any nephridia at all in Uncinais littoralis.
The absence of nephridia in the anterior segments of the
body, however, also characterises certain earthworms. It
was originally described by Perrier in Pontodrilus, and all
the species of this genus (6) are in the same condition.
More recently Benham and Risen have shown that the
same state of affairs characterises the aquatic Geoscolecid
Sparganophilus. A distinction therefore between the
Limicolae and Terricolse of Claparede quite breaks down.
That these genera have no gizzard or calciferous glands
(or at most the rudiments of a gizzard) is evidence of general
degradation, which may have something to do with their
aquatic or semiaquatic existence. It suggests too that
the simplification in structure of the Limicolae of Claparede
may be rather due to degeneration than to the retention of
primitive characters.

Among the earthworms, however, the single pair of
nephridia to each segment is far from being the rule. In
a large number of genera the nephridia are multiple. Two
pairs in each segment exist in BracJiydriliis ; three pairs in
Trinephrus; and Eisen has lately shown that in certain
North American Benhamias there may be three or four
distinct and separate pairs each with its own internal funnel
and external pore. The complexity of the excretory
system culminates in Perichceta where a single segment may
be furnished with probably at least one hundred external
nephridiopores. It is, however, a question whether in
this latter case there is really an intercommunication be-
tween the several nephridia of each segment, and between
those of adjacent segments as has been alleged by Spencer

SOME RECENT MEMOIRS UPON 0L1G0CHJETA. 197

and myself. The matter requires renewed investigation.
In any case Bourne, Vejdovsky and I have shown that the
" plectonephric " condition, as Benham has termed these
diffuse nephridial tubes, is preceded by a series of paired
nephridia one pair to each segment. This has been proved
in Pericktzta, Qciochcetus and Megascolides. The nephridium
elongates and becomes thrown into loops, each loop finally
appears in Megascolides to break away and to form a
distinct and separate nephridium. It is clear, therefore,
that whether or not the connection is retained in Octochcetris
and Perichceta there is originally a connection, so that that
matter is of less importance than the alleged intercom-
munication from segment to segment. This multiple
arrangement of the nephridia is only found in the families
Acanthodrilidae, Perichsetidae and Cryptodrilidae, and is the
principal argument for uniting them into one superfamily,
Megascolicides, as I have done in my Monograph. Brachy-
drihts, however, is a member of the family Geoscolicidse,
but it has only two pairs of nephridia to each segment ;
there is nothing like the complicated system of Perichceta.
This family Geoscolicidse has been through the recent re-
searches of Rosa and Michaelsen brought still nearer to the
Lumbricidse. It was always difficult to separate them,
mainly on account of the aquatic Criodrilus, now it is
practically impossible unless we accept Michaelsen's inter-
mediate family Criodrilidse. The ornament setae which
used to be a distinctive mark of the Geoscolicidse have
been found by Michaelsen in Allolobophora moebii and
in A. lonnbergi ; many Geoscolicidae, e.g., Microckceta are
distinguished by the fact that instead of a single pair
of spermathecae in each of those segments which con-
tain them there are a considerable number of minute
pouches ; this distinction, however, falls to the ground
since more than one Allolobophora is now known to
possess the same character — which has moreover been met
with in Perichceta. It is in these two families that most
instances are met with of total absence of spermathecae ;
Kynotus, a Madagascar genus, is anteclitellian like the
Lumbricidae, and in short it seems impossible to lay down any

ig8 SCIENCE PROGRESS.

set of characters which should absolutely separate the two
families. Several members of the two families are aquatic ;
thus among the Geoscolicicke Bilimba (with which Michaelsen
now suggests to unite Horst's A nnadri/us and Glyphidrilus),
Criodrilus, whose range the same author has lately ex-
tended to South America, Alma and Sparganophilus. Of
Lumbricidae Allurus is the only form which is often
aquatic. Michaelsen has dwelt upon the fact that all of
these, with the exception of Sparganophilus, have the
body generally or at least the posterior region markedly
quadrangular in outlines with the setae implanted at the
four corners. This is an apparent consequence or at least
concomitant of aquatic life which is more curious than
explicable. So much then for recent modifications of the
systematic arrangement of the group. I shall deal finally
with various anatomical and histological discoveries which
have a general interest unconnected with systematic rela-
tions. The most important work under this heading is
undoubtedly the recent investigations into the structure of
the remarkable family Eudrilidae, a well-defined family
whose boundaries have not become in the least indistinct
by the discovery of new forms. The family is remarkable
on account of its distribution as well as on account of
certain anatomical peculiarities. It is limited to tropical
Africa — to the Ethiopian region of Sclater, with the sole
exception of the type genus Eudrilus, whose ubiquitous-
ness, however (America, West Indies, India and the East
generally, New Zealand, etc.), makes one suspect direct
transference by man. This family is chiefly interesting on
the anatomical side by reason of the illustration which it
gives of two phenomena, viz., substitution of organs and
change in function of organs.

In all Oligochaeta the ovaries are paired (rarely
unpaired) structures which arise from the peritoneal
epithelium of the earthworms invariably the thirteenth
segment. They are totally unconnected with the oviducts
whose open mouths are placed exactly opposite to them.
In the Eudrilidae these gonads are enclosed in sacs
which communicate with a system of sacs the complexity of

SOME RECENT MEMOIRS UPON OLIGOCHMTA. 199

which varies in different genera, and of which it would be
impossible to give any detailed account without the assis-
tance of figures. There is a separate receptaculum ovorum
like that of the common earthworm, with which is connected
the oviduct. This system of sacs, through which the ova
can travel in so far as there are no physical hindrances, also
contain sperm, and play the part of spermatheca? or a sperma-
theca. They commonly open by a single ventral pore ;
sometimes the structures are paired as in the genus Eudrilus
itself. Now these pouches generally contain sperm, and
there is therefore the possibility of the ova being impreg-
nated within them ; Michaelsen has even suggested that
some species are viviparous. In a few genera, for example
in Heliodrilus, these pouches do not communicate with the
exterior except through the oviducts. They appear to do
so by a large ventral pore, but when careful sections are
made it is found that this pore is the mouth of a closed sac,
exactly like a spermatheca, which is enclosed within the
large pouch. Thus the ccelomic nature of this system of
sacs is established on anatomical grounds, and develop-
mentally they have been shown, at least in one genus, to
be derivatives of the intersegmental septa just as are the
sperm sacs of other earthworms ; their cavities are therefore
separated portions of the general ccelom. But, as already
mentioned, in most cases they do open on to the exterior
directly by a conspicuous orifice, and contain sperm which
probably finds its way into them by this orifice. The fact
that in some cases these sacs contain structures which are
precisely like the spermathecae of other earthworms, and
that in other cases where they open directly on to the
exterior the character of the lining epithelium changes near
to the orifice, becoming distinctly columnar, suggests that
we have to do here with the substitution of sacs derived
Irom the septa for the true spermathecae which are gradually
disappearing, only the extremity being left in the majority
ot cases. The second point with which I wish to deal
concerns the calciferous glands. Most, but by no means
all, earthworms possess one or more pairs of these organs,
which are attached to and open into the cesophagus. What-

200 SCIENCE PROGRESS.

ever may be their functions they contain crystals of car-
bonate of lime, and have a rich vascular supply, the lining
epithelium being much folded and therefore extensive. In
some Eudrilidae these structures are absent or rather are so
altered that they are nearly unrecognisable as calciferous
glands. At the same time they have become more numerous.
The structure is altered in that instead of an extensive lumen
produced by the folding of an excretory epithelium there is
a very short sac connected with the oesophagus, which
is, however, enveloped by an extensive coating of cells
which I regard as ccelomic cells, and among which meander
abundant blood-vessels. These ccelomic cells, where they
abut upon blood-vessels, very often lose their oval or
rounded form and become columnar and at the same time
more darkly staining. They surround the blood-vessel as if
it were the lumen of a secreting gland, the cells themselves
having acquired the appearance of a secreting epithelium.
These phenomena suggest that we have to do here with a
change of function on the part of the calciferous glands ; that
their function of producing carbonate of lime, that their
connection with alimentation has disappeared or is dis-
appearing, and that a new function more intimately connected
with the vascular system has supervened. There is a
certain analogy here with the vertebrate liver which has
certainly more functions than that of pouring bile into the
intestine, though originally it may have been merely an
annex of the alimentary canal.

In histology there is only one matter to which I shall
direct the attention of the reader. It concerns the minute
structure of muscular fibres in the Oligochoeta. The careful
researches of Cerfontaine have established the fact that the
Oligochseta, like the leeches, have muscular fibres which
consist of an outer sheath often radiately striated, the
muscular substance, and a soft central core. Hesse, how-
ever, while admitting this, goes a step further and
endeavours to prove a resemblance to the muscular fibres
of the Nematoidea. He figures in the Enchytraeidae and
in the Lumbricidse a gap in the sheath of the fibre through
which the soft less-modified protoplasm of the interior com-

SOME RECENT MEMOIRS UPON OLIGOCH^ETA. 201

municates with a pear-shaped nucleated body outside. If
these observations prove ultimately to be correct it is clear
that there is a close resemblance in this particular between
the Oligochseta and the Nematoidea.

BIBLIOGRAPHY.

Beddard. A Monograph of the Order Oligochseta, Oxford :

Clarendon Press.
ElSEN. Pacific Coast Oligochaeta. Mem. Calif. Acad. Set., vol. ii.,

1895-96.
Hesse. Beitrage zur Kenntniss des Baues der Enchytraeiden.

Zcitschr. fur iviss Zoo/., 1893.
HESSE. Zur vergleichenden Anatomie der Oligochaeten. Ibid.,

1894.
MlCHAELSEN. Zur Kenntniss der Oligochaeten. Abh. Nat. Ver.,

Hamburg, 1895.
H. F. MOORE. On the Structure of Bimastos palustris. Journ.

Morph., 1895.
J. P. MOORE. The Anatomy of Bdellodrilus illuminatus. Ibid.
ROSA. Allolobophora dugesii. Boll. Mus. Zooi, Torino, 1895.
BOURNE. In Quart. Journ. Micr. Sci., 1894.
SMITH. Notes on Species of North American Oligochaeta. Bull.

Illinois State Lab.

F. E. Beddard.

NOTES ON ATOMIC WEIGHTS.

IN a former article 1 a sketch of the state of our know-
ledge as to the relative atomic weights of hydrogen and
oxygen was given. It was there shown that although the
great mass of the evidence was in favour of the atomic
weight of oxygen being about 15*88 times that of hydrogen
yet there was a certain amount of experimental work by
well-known and tried observers which seemed irreconcilable
with this result, the chief paper (1) being that of Professor
Julius Thomsen of Copenhagen, and based on the propor-
tion by weight in which ammonia and hydrochloric acid
combine to form neutral ammonium chloride. In a short
paper by the late Lothar Meyer (2) it was proved con-
clusively how little value could be attached to a determina-
tion of this nature however accurate and careful the mani-
pulative work might be.

Any hopes which might have survived in the minds of
the most ardent follower of Prout, that the atomic weight
of oxygen is exactly sixteen times that of hydrogen, must
now be dispelled by the recent publications of E. W.
Morley (3) and of Thomsen (4) himself. The work of
Morley is so conclusive, and has been carried out with
such untiring patience and skill, that to any one who reads
the clear account which he gives of his methods and of the
various checks employed, it must be quite evident that that
type of worker of whom we regard Stas as the chief is not
yet extinct, in spite of the prevailing view that one must
publish as many papers as possible in the least possible
time before one can be said to engage in " original re-
search ". Morley's scheme for the complete determination
of the relative atomic weights of oxygen and hydrogen is
a most ambitious one, and, although his results are quite
conclusive now, it is much to be regretted that bad health
and other circumstances over which he had no control
(such as a workman pushing a brick through a wall on to a

1 August, 1894.

NOTES ON ATOMIC WEIGHTS. 203

delicate piece of glass apparatus) have up to the present
time prevented him from carrying out his original pro-
gramme in its entirety.

The paper consists of four distinct parts —

I. The determination of the weight of a litre of oxygen.

II. The determination of the weight of a litre of

hydrogen.

III. The ratio by volume in which these two gases

combine to form water.

IV. The synthesis of water from known weights of

hydrogen and oxygen, the weight of the water
formed being also accurately determined.

It would be impossible to give any idea of the precau-
tions taken to obtain results free from all objections in a
sketch so short as this must be, for such details the
original memoir must be consulted ; only a summary of
the results obtained can here be given.

Three methods were adopted to determine the weight
of a litre of oxygen. In the first method the barometer
and thermometer were used, and the gases weighed in
balloons holding in three of the experiments about 9 litres,
and in the other six about 21^ litres.

In the second method a globe of pure and dry hydrogen
was used as the standard for temperature and pressure, the
globe containing the oxygen having its pressure deter-
mined at the same temperature as that of the hydrogen
by means of a very sensitive differential manometer.

In the third method the globes were filled with oxygen
when they were immersed in melting ice and the pressure
accurately determined at the moment of closing. This
method had the disadvantage of wetting the surface of the
globes, and probably thereby changing their weight (although
this was duly investigated).

The values obtained by these three methods for the
weight of 1 litre of oxygen under normal conditions of
temperature and pressure at sea level in lat. 450 were

By use of thermometer and manometer- 0 = 1-42879 + "000034.
By compensation - 0=1-42887 + -000048.

By use of ice and barometer - - 0 = 1*42917 + -000048.

204 SCIENCE PROGRESS.

From various considerations taking into account errors
incidental to certain methods and liability to constant errors
Morley gives the most probable value as i "42900 ±0*000034.

In the same way experiments were made with hydrogen
and in live series but practically by three methods.

First method was practically the same as the first series
of oxygen experiments.

Second method was like the third oxygen series.

Third method utilised the power of absorbing hydrogen
possessed by palladium. The hydrogen was weighed in
the palladium and expelled into globes, and its volume and
pressure determined at the temperature of melting ice.
Series III., IV. and V. were made by this method, but
the apparatus employed varied somewhat in the various
series.

The values which result from these experiments are

Series I. Dh = -089938 gram.

Series II. Dh = '089970 gram.

Series III. Dh = -089886 + -0000049 gram.

Series IV. Dh = -089880 + -0000088 gram.

Series V. Dh = -089866 + -0000034 gram.

The higher results of Series I. and II. are possibly due to
some constant error, probably traces of mercury vapour.
The most probable value is

Dh = -089873 + 0*0000027 gram.

Part III. of the paper begins with a sketch of the methods
it was proposed to employ to determine the volumetric
composition of water. Of the three methods proposed Morley
unfortunately has only been able to carry out the one which
is the least satisfactory, viz., the determination of the
density of electrolytic gas and of the excess of hydrogen
over and above what the oxygen can unite with. Leduc
made a similar density determination, but apparently
assumed that the hydrogen and oxygen were in the exact
proportions in which they would recombine to form water.
Morley found that he always had an excess of hydrogen
when he kept his voltameter in ice and water, but that
when the temperature was allowed to rise to about 20° C.
then oxygen was in slight excess, so that no doubt at a

NOTES ON ATOMIC WEIGHTS. 205

certain temperature the gases do come off in atomic propor-
tions. In each experiment the weight of the gases given
off was about 23 grams.

The weight of a litre of the gas thus given off from
solution of soda made from clean sodium was —

°'53551Q ± o-ooooio,
and corresponds to a mixture of one volume of oxygen with
2*00357 volumes of hydrogen, but the excess of hydrogen
was found to be -ooo88 giving therefore the ratio in which
the gases combine as 1 : 2*00269.

Part IV. gives an account of experiments in which
hydrogen was weighed in palladium foil, oxygen was
weighed in a globe, these were then made to combine, and
the water produced was weighed also.

From these experiments we get the following values for
the atomic weight of oxygen : —

(1) From the ratio of hydrogen and oxygen, - - 15-8792

(2) From the ratio of hydrogen and water, - - - 15-8785

or as a mean, ------ 15879

From Parts I., II., III. of the memoir we get

1*42000 2 0

—17~ x = 15-879

•089873 2-00269

How excellent Morley's work is can perhaps best be
seen by comparing his results with the means of those of
previous experimenters,

Rayleigh's

summary. Morley.

Density of oxygen at Paris, - - 1-42961 1-42945

Density of hydrogen at Paris, - - -08991 -089901

Ratio of densities mean of all previous determinations, - - 15-9005
Ratio of densities, Morley's, 15-9002

Ratio of combining volumes, Morley, - 2*00269
„ ,, Scott, - 2*00285

,, ,, Leduc, - 2*0037 (corrected = 2 0024)

Although the results obtained by Thomsen agree
wonderfully well with those of Morley it is not because his
apparatus and his methods of working are so carefully
elaborated. On the contrary what strikes one most forcibly
is the extreme simplicity of the apparatus and mode of

206 SCIENCE PROGRESS.

working it as well as the neglect of certain precautions
which could well have been taken, and ought to have been
taken in an attempt to settle such an important constant as
the present ; such precautions as to weighing with counter-
poises of equal volume, for example, seem to have been
neglected.

The method was to determine, firstly, the weight of
hydrogen given off from unit weight of aluminium when
dissolved in strong potash solution ; secondly, by supplying
oxygen to a small combustion chamber so as to burn the
hydrogen evolved from a known weight of aluminium, and
collect all the water formed in the apparatus, one gets thus
the gain of the equivalent amount of oxygen to the hydro-
gen and to the aluminium. The only corrections not of
the simplest order were due to the oxygen and hydrogen
remaining in the apparatus or which had to be evolved after
the combustion had ceased. It was not found possible to
burn all the hydrogen evolved completely as the current
became so very slow when a very little aluminium remained
undissolved. The aluminium did not require to be perfectly
pure as long as it gave off no other gas than hydrogen. It
was found that 162 "3705 grams of aluminium gave off
1 8*1778 grams of hydrogen giving the ratio

Hydrogen

p — = 0*111902 + "000015

Aluminium

as the mean of twenty-one experiments.

The weight of oxygen required to combine with 86*9358
grains of aluminium (or rather with the hydrogen evolved
by its solution in potash) was found to be yyiSyG grams
from which we get the ratio

°*W^ = -88787 ±00001 S
Aluminium

from which two results we get

O -88787

5- = — — = 7 '9345

Ho '11190

or — = i?-86qo + "oo22
H D ~

We seem to have every reason now to regard it as com-
pletely proved that the atomic weight of oxygen is 15*87 to

NOTES ON ATOMIC WEIGHTS. 207

r 5*88 times that of hydrogen, the higher value being in all
probability the more correct.

Having now satisfactory determinations of our funda-
mental ratio we still require other ratios to be able to de-
termine conveniently the atomic weights of many elements.
If an element forms many compounds with oxygen it is
never safe to conclude without the most rigorous proof that
we have a pure oxide absolutely free from the other oxides
of the same element. Hence determinations of atomic
weights made by the reduction of oxides to the element or
of one oxide to a lower one or of the oxidation of an
element to an oxide or of one oxide to a higher oxide must
always be accepted with caution. The use of the haloid
compounds (especially those of bromine), of many elements,
is of the greatest value, and for this we require an exact
knowledge of the ratio bromine : oxygen. For this we
depend chiefly on the classical work of Stas. The publica-
tion of the complete works (5) of J. S. Stas under the able
editorship of Professor W. Spring, of Liege, enables every
one now to obtain in an elegant and convenient form these
models and masterpieces of accurate research which were
formerly so difficult to procure. How great the contrast
between the work of Stas and too much of that turned out
at the present day a glance at almost any page of his
works will show. Every step was proved most conclusively,
however simple and even axiomatic it may seem to us now,
before he proceeded to more elaborate propositions and
deductions. For instance, in his Nouvelles Recherches he
begins by proving that ammonium chloride prepared from
absolutely different sources and purified in different ways
always contains exactly the same proportion of chlorine,
and that the same weight of each sample precipitated
exactly the same amount of silver from its solution in
nitric acid. He obtained his ammonia from ordinary sal
ammoniac after destroying any organic bases by a treat-
ment with aqua regia, and from commercial ammonium
sulphate by a similar purification, by heating it to a high
temperature with strong sulphuric acid, and then oxidation
with nitric acid, and from potassium nitrite by reduction in an

2o8 SCIENCE PROGRESS.

alkaline solution with purified metallic zinc. The ammonium
chloride was sublimed now in a current of ammonia gas,
now in vacuo, but the results obtained showed that for the
complete precipitation of 100,000 parts of silver, 49,592 to
49,602 parts of ammonium chloride were required. In
other words, the extreme difference in a large number of
determinations carried out with very considerable modifica-
tions only amounted to one part in five thousand.

Having thus proved that a compound always contains
the same proportion of its constituent elements it was
essential for his purpose as well as for the complete
establishment of the atomic theory to prove that the equiva-
lent weight of an element was not affected in the slightest
degree by the various elements with which it might
combine. To take an example, silver combines with
iodine to form the iodide, and with iodine and oxygen to
form the iodate, and these compounds are represented by
the formulae Agl and Ag I03 respectively. It was just
possible, one might even say probable, that the ratio of silver
to iodine in the one compound might not be the same as
that in the other, but that it would be modified by the large
quantity of oxygen present in that other substance. If,
however, the elements consist of small particles alike in all
respects, such a variation would be impossible, and the
relative masses of silver and iodine in the iodide and in the
iodate must be absolutely the same. To prove this may
seem very easy, but Stas found it by no means so, lor
whenever he prepared his silver iodate by precipitation from
the nitrate, after the reduction with sulphurous acid there
was always a small excess of silver over and above the
iodine present. This he finally traced to a minute quantity
of the nitrate being carried down mechanically by the
iodate, but so firmly held that no amount of washing would
remove it. By using other soluble salts of silver such as
the sulphate and the dithionate, however, he was able to
prepare silver iodate so pure that on reduction to silver
iodide not the slightest trace of either silver or iodine re-
mained in excess. In the case of that prepared from the
nitrate the excess of silver only amounted to one part in

NOTES ON ATOMIC WEIGHTS. 209

3,000,000. These simple experiments give us some idea
as to how hard it is to obtain even very simple compounds
in a state of absolute purity. Having thus laid the founda-
tions for his further work, and shown that the combining
proportions of elements are mathematically exact, Stas con-
sidered no labour too great if thereby he could obtain more
accurate values for these proportions. Any work done
since his determinations has only tended to uphold his
values and to increase our admiration for his work.

The great value of very accurate experimental work
has been most strikingly exemplified by Lord Rayleigh's
determinations of the density of nitrogen (6). He
found that the nitrogen which he could obtain from air
alone by removing the oxygen was very little denser, but
was always denser than that prepared from the air with the
aid of ammonia by Harcourt's method, and that the nitro-
gen prepared from ammonia or from any compound had
always the same density, and that this was still lighter than
that partly from air and partly from ammonia. From this
he concluded that besides nitrogen the atmosphere must
contain another constituent still denser, which like nitrogen
resisted the action of iron and copper as well as their oxides,
even when very strongly heated. By combining the
nitrogen with oxygen after the method of Cavendish, or by
causing the nitrogen to unite with metallic magnesium, a
new gas to which the name of argon has been given was
finally separated by Rayleigh and Ramsay after much
laborious work. The detection in the atmosphere of a
constituent hitherto unsuspected as well as its isolation are
apparently only the first fruits of a number of more or less
startling discoveries Mowing directly from Lord Rayleigh's
very accurate work. The molecular weights of argon
(7) and helium (8) are respectively 40 and 4, and if their
molecules are monatomic this would give us the same
numbers for their atomic weights, but if the molecules are
diatomic, as is probable, these numbers would be halved for
the atomic weights. It is far from certain that either what
we call argon or what we call helium is not a mixture of
several similar substances.

210 SCIENCE PROGRESS.

Several atomic weights have been redetermined with
great care, and of these determinations perhaps those
of T. W. Richards of barium and of strontium are the most
accurate and most interesting. By an exhaustive research
on barium bromide he deduces the value Ba = 137*434
(O = 16) (9). From a similar study of barium chloride the
value Ba = 137*440 is deduced (10).

This value is notably higher than that usually accepted
and is no doubt due to the careful elimination of small
quantities of strontium and calcium which have contaminated
the preparations of earlier experimenters. From a study of
strontium bromide Richards found Sr = 87*659 (O = 16)

Still more recently the atomic weight of zinc has been
determined by Richards and Rogers again by means of the
bromide and precipitation with silver, and as a mean they
find the value (Zn = 65*404) (O = 16) (12).

In all the above determinations Richards estimated the
percentage of silver in his haloid silver salt and showed it
to be identical with that found by Stas, thus placing his
work on the same footing and guaranteeing in this way its
very high accuracy.

In 1888 two other American experimenters, Burton and
Morse (13), published the results of their work on the same
atomic weight which they arrived at by means of the con-
version of the metal into the oxide by treatment with nitric
acid and ignition of the nitrate. Although their work
agrees throughout very well the value found is lower than
that of Richards, due no doubt to the retention by the
oxide of oxides of nitrogen as Marignac pointed out. In
defending their work against this objection they expose
their want of knowledge of the commonest reactions in such
a way as to make one distrust all their work. The perusal
of their paper provides much food for reflection of a serious
nature although it does give a certain amount of instruction
as well as amusement. They carry out their weighings to
*ooooi of a gram and pretend to detect differences of this
minute amount in porcelain crucibles which have been
heated up to the melting point of steel. In their account

NOTES ON ATOMIC WEIGHTS. 211

of the purification of metallic zinc by distillation in vacuo it
is rather odd to find it stated that indiarubber tubing with
glycerine joints could not be used because the vapours of zinc
and of glycerine interact. What pressure of the vapour of
each is likely to exist at the highest temperature to which the
joints would ever be subjected ? The presence of gold in
the nitric acid distilled from a platinum still, and coming
from the gold solder used in it sounds also rather peculiar.
One knows that very finely divided gold will dissolve in
fuming nitric acid if kept cold, but one could hardly have
thought of finding it as an impurity in nitric acid prepared
by distillation. But the gem of all the statements comes at
the end of the paper when these two rising experimentalists
proceed to criticise Marignac's work (14), and finally to
teach him and us how we ought to test for oxides of nitro-
gen by means of starch and potassium iodide. After
proving to their own satisfaction by a process which cannot
reveal the presence of any of these oxides that they are
therefore obviously absent, they conclude that Marignac
was ignorant of the necessary precautions which must be
taken to exclude oxygen, especially that of keeping the
solution practically boiling so that the steam may keep out
the air. It is usually accepted as a well-established fact
that the delicacy of this reaction decreases rapidly with rise
in temperature, and that the colour goes completely before
the boiling point is reached, even in the presence of
relatively large quantities of free iodine.

Amongst other noteworthy determinations of atomic
weights made recently are those of Winkler, who finds
the values Ni = 58*91 and Co = 59*67 by means of the
reaction between the chlorides and silver (15); and still
more recently Ni = 5871 and Co = 59*37 (16) by deter-
mining the amount of iodine required to unite with the
pure metal. Winkler uses the value Ag = 107*66, if we
use O = 16 or Ag = 107*93 these last values become

Ni = 58-863
Co = 59*517

The determinations of the atomic weight of boron by

15

212 SCIENCE PROGRESS.

Ramsay and Acton (17), as well as by Rimbach (18), are
very interesting as examples of various methods of attacking
this problem, and which give fair results, but they can
hardly be said to have given results possessing greater
accuracy than those of Abrahall (19).

Of all the elements of which the atomic weights are still
in doubt, and of which the determinations are very unsatis-
factory, by far the most interesting is undoubtedly tellurium.
According to the periodic classification of the elements it
ought, as is well known, to have an atomic weight less than
that of iodine, but all the most satisfactory determinations
are irreconcilable with this, and make the atomic weight
notably higher than that of iodine. The experiments made
in recent years both by Brauner (20) and by Wills (21)
agree in this, no matter what method is adopted as long as
it is one which gives concordant results. The latest deter-
minations, those of Staudenmeier (22) which start from
telluric acid, give, according to him, the values 127*6,
127*1, and 127*3 f°r three series of experiments in which
different ratios were determined. He takes as his standard
O = 16 and H = 1*0032. Staudenmeier upholds that tel-
lurium is an element in opposition to Brauner who at one
time maintained that it was a mixture of true tellurium with
a higher homologue, but now concludes that this is very im-
probable, and since the discovery of argon suggests that
the assumed impurity may be a homologue of argon.
Speculations of this nature are strongly to be discouraged
and condemned, especially when their basis is nothing
more than the assumed abnormality in the periodic ar-
rangement of the elements coupled with a very decided
want of agreement in the results of an experimenter's own
work obtained by different methods. They may afford an
easier way out of a difficulty than by working steadily at
the causes of such discrepancies, but afford at best but a
feeble and undignified cover for one's retreat.

P.S. — About the middle of last month, and after the
above article was written, Thomsen (23) published the
results of some new determinations of the densities of
oxygen and hydrogen. The oxygen was prepared by

NOTES ON ATOMIC WEIGHTS. 213

heating a mixture of potassium chlorate and ferric oxide,
and the hydrogen from a solution of caustic potash by the
action of metallic aluminium. The values found were : —

Weight of one litre of oxygen at 0° C. and 760 mm. pressure, at
sea-level in Latitude 45° - - - = 1*42906 grams.
And of hydrogen similarly = -089947 gram.

From these he deduces the ratio of the volumes in which
they must combine to form water to be 1 : 2*00237.

BIBLIOGRAPHY.

(1) Thomsen, J. Experimentelle Untersuchungen zur Feststel-

lung des Verhaltnisses zwischen den Atomgewichten des
Sauerstoffs und Wasserstoffs. Zeitschrift fur physikalisdie
Chemie, xiii., 398, 1894.

(2) Meyer, L., und Seubert, K. Ueber das Verhaltniss der

Atomgewichte des Wasserstoffes und des Sauerstoffes.
BericJite ler deutsclien chemischen Gesellschaft, xxvii., 2770-
2773, 1894.

(3) Morley, E. W. On the Densities of Oxygen and Hydrogen,

and on the Ratio of their Atomic Weights. Smithsonian
Contributions to Knoivlcdge, No. 980, 1895.

(4) THOMSEN, J. Experimentelle Untersuchung iiber das Atom-

gewichts verhaltniss zwischen Sauerstoff und Wasserstoff.
ZeitscJirift fur anorganische CJiemie, xi., 14, 1896.

(5) STAS, J. S. Giuvres completes. Edited by Professor W.

Spring, Bruxelles, 1894.

(6) Rayleigh, Lord. On an Anomaly Encountered in Deter-

minations of the Density of Nitrogen Gas. Proceedings of
the Royal Society, lv., 340, 1 894.

(7) Rayleigh and Ramsay. Argon, a New Constituent of the

Atmosphere. Philosophical Tra?isaction±, clxxxvi., A. 223,
1895.

(8) Ramsay, W. Helium a Constituent of Certain Minerals.

Journal of the CJiemical Society, Ixvii., 684, 1895.

Langlet, N. A. Ueber das Atomgewicht des Heliums.

Zeitschrift fur anorganische Chemie, x., 289, 1895.

(9) Richards, T. W. A Revision of the Atomic Weight of

Barium ; the Analysis of Baric Bromide. Proceedings of
the American Academy of Arts and Sciences, xxviii., 1-30,
1893.

214 SCIENCE PROGRESS.

(10) RICHARDS, T. W. A Revision of the Atomic Weight of
Barium; the Analysis of Baric Chloride. Proceedings of the
American Academy of Arts and Sciences, xxix., 55-91, 1893.

(n) RICHARDS, T. W. A Revision of the Atomic Weight of
Strontium ; the Analysis of Strontic Bromide. Proceedings
of the American Academy of Arts and Sciences, xxx., 369-
389, 1894.

(12) RICHARDS, T. W. and ROGERS, E. F. Neubestimmung des

Atomgewichtes von Zink ; analyse von Zinkbromid. Zeit-
schrift fiir anorganische CJiemie, x., 1-24.

(13) Morse, H. N. and Burton, W. M. The Atomic Weight

of Zinc as Determined by the Composition of the Oxide.
American Chemical Journal, x., 31 1-32 1, 1888.

(14) Marignac,C.DE. Verification de quelques poids atomiques :

Zinc. Archives des sciences physiques et naturelles [3] x., 193,
1883.

(15) Winkler, C. Ueber die vermeintliche Zerlegbarkeit von

Nickel und Kobalt und die Atomgewichte dieser Metalle.
Zeitschrift fiir anorganische Chemie, iv., 10 and 462,
1893.

(16) Winkler, C. Die Atomgewichte von Nickel und Kobalt.

Zeitschrift fiir anorganische Chemie, viii., 291, 1895.

(17) RAMSAY, W. and ASTON, E. The Atomic Weight of

Boron. Journal of the Chemical Society, lxiii., 207, 1893.

(18) RlMBACH, E. Zum Atomgewicht des Bors. Berichte der

deutschen chemischen Gesellschaft, xxvi., 164, 1893.

(19) ABRAHALL. The Atomic Weight of Boron. Journal of the
Chemical Society, Ixi., 650-666, 1892.

(20) BRAUNER, B. Experimental Researches on the Periodic

Law. Journal of the Chemical Society, lv., 382-411, 1889.

(21) Wills, W. L. On the Atomic Weight of Tellurium. Journal

of the Chemical Society, xxxv., 704-713, 1879.

(22) Staudenmeier, L. Untersuchungen iiber das Tellur.

Zeitschrift fur anorganische Chemie, x., 189, 1895.

(23) Thomsen, J. Experimentelle Untersuchung iiber die Dichte

des Wasserstoffes und des Sauerstoffes. Zeitschrift fib
anorganische Chemie, xii., 1-1 5, 1896.

Alexander Scott.

THE STELAR THEORY; A HISTORY AND A

CRITICISM.

PART II.
THE METAMORPHOSES OF THE STELE.

IT is clear that the theory of polystely forms an
integral part of the general stelar doctrine, and we
can hardly refuse to accept its main idea. But though each
stele in the polystelic stems of, for instance, Aiiricula Ursi
and many Polypodiacea^ is clearly the equivalent of the
whole cylinder in the hypocotyl of the same plants, cases
exist in which we seem forced to consider as steles,
vascular strands which have none of the characters of the
cylinder left about them.

Deriving our idea of the typical stele from the mono-
stelic organ, we come to consider it as essentially cylindrical
and radially symmetrical. It is true that diarch roots are
bilateral in structure, and the primary root and hypocotyl of
very many ferns being diarch the steles of a great number
of their stems are likewise diarch and hence bilateral. And
this bilaterality often extends to the shape of the stele which
becomes oval or band-shaped instead of circular in transverse
section, the two protoxylems being situated at the extremi-
ties of the figure. Another step is for the stele to become
more or less semilunar in transverse section, so that it is no
longer symmetrical about the plane passing through the
protoxylems, but only about the bisecting plane perpendi-
cular to this. And further the protoxylems may lose their
symmetrical arrangement, or one only may be present, and
this may be excentrically placed (Angiopteris). We clearly
could not tell that such strands were steles if we had no
knowledge of their connexions and disposition. At least
as far as tissue arrangement goes they may often be said to
have lost those characters which entitle them to the name.
A similar difficulty meets us in the case of the vascular
strands in many fern leaves. Undoubted steles found in

216 SCIENCE PROGRESS.

the petiole, after repeated branchings gradually lose the
phloem from their upper sides, and thus come to possess the
collateral structure of the bundle of a Phanerogamic leaf.
On the other hand the curved bundle in the petiole of
Osmunda is certainly a meristele, if we may judge from its
connexion with the bulky central cylinder of the mono-
stelic stem, yet it is surrounded by a complete mantle of
phloem, and indeed conforms in structure to many true
steles (cf. 1 8). We may probably draw the same con-
clusion as to the " petiolar steles " of Gleicheniacese (19).

Similar facts appear to obtain in the polystelic genera of
Phanerogams, upon which we may expect much new light
from as yet unpublished researches. One instance is,
however, too instructive to be omitted. A number of
distinct steles arranged in a circle enter the peduncle of
Auricula Delavayi (8, p. 304), fuse laterally, and become
indistinguishable from a monostele, the central extra-stelar
tissue passing over into pith.1 Van Tieghem warns us (10,
p. 768) not to confound such a structure formed in an
essentially polystelic stem with an essentially monostelic
stem. But if this sort of thing may occur, what guarantee
have we that an "essentially monostelic" stem is really
essentially monostelic, or, for the matter of that, that an
" essentially polystelic " stem is really essentially polystelic ?
If a stele can become a collateral bundle in the course of a
shoot system, the same transformation may very well occur,
or a collateral bundle may become a stele, in the course of
descent ; at least we are quite debarred from dogmatically
drawing or denying homologies between the one and the
other. Of course we can speculate, and in some cases
claim a fair degree of probability for our speculations,
especially when we have a minute knowledge of all the
facts in the anatomy of a given group, but since it is impos-
sible to draw a sharp line between a stele and a vascular
strand that is not a stele we are clearly not on very firm
ground. There is certainly nothing to surprise us in this ;

1 A similar state of things appears to obtain in some of the Palm roots
investigated by Mr. Cormack.

THE STELA R THEORY. 217

the instructive fact is that "there's such divinity doth
hedge " a stele — indeed any morphological conception, as in
almost every fresh case to prevent for a time our realisation
of the truism that " Nature knows no sharp boundaries ".
In the stelar doctrine, we have, no doubt, a classification
that enables us to perceive a little more closely the direc-
tions along which the various types of vascular system in
the higher plants have been evolved, and that after all is
the most we can expect.

DEVELOPMENTAL EVIDENCE BEARING ON THE STATUS

OF THE STELE.

We have now to consider the developmental basis
of the stelar theory. Let us take the Phanerogams first.
It is well, as Dr. Scott (20) has already pointed out
in this journal, to draw a distinction between de-
velopment from the embryo, and development of the
various axes from their permanently embryonic grow-
ing points. It is clear, on reflection, that the former
alone is comparable to ontogenetic development in animals,
though it would be a mistake to suppose that the latter is
not of importance to morphology. In the comparatively
few types of monostelic plants with the anatomy of whose
embryos we have a sufficient acquaintance, it appears
that both in the plumule and radicle there is really a
clear separation at the apex between central cylinder
and cortex (plerome and periblem). But it is certainly
open to doubt whether this distinction, as Hanstein
thought, is really maintained at the growing points of the
various axes throughout the life of the plant. Into the
history of the differences of opinion on this point we need
not enter. The inherent difficulties of arriving at valid
conclusions from observations have been nearly as powerful
as the subjective causes which have evidently influenced
the views of the observers in creating the extraordinary
discrepancies which exist between the various accounts.

The method employed by Ludwig Koch (21 and 22),
who recognised that the state of things at the growing
point was likely to differ at different epochs of growth, and

218 SCIENCE PROGRESS.

that hence conclusions drawn from observation of a few
sections could not be final, marks a great advance on
previous work. Koch claims to have proved (22), in Syringa
and Berberis, that the single layer of cells immediately
beneath the dermatogen, i.e., the periblem of earlier ob-
servers, divides periclinally, during a period of leaf forma-
tion, across the actual apex of the shoot, thus giving rise to
three or four superposed layers of cells. It is clear that,
if this is the case, all but the uppermost of these layers
must become part of the plerome when the apex passes
back to the state of possessing a single layered periblem.
But though our author has convinced himself that this
actually happens, his figures are not decisive. Most of the
periclinal divisions which he shows in the periblem of the
Lilac (Taf. xvi.) are clearly in connexion with the forma-
tion of the leaf rudiments. In no case are such divisions
shown across the actual apex. In fig. vi. periclinal walls are
drawn in two periblem cells removed by one cell from
the cell-group obviously concerned in the formation of a
leaf rudiment, but these walls are also removed by one
or two cells from the centre of the flat growing point,
and considering how much this free surface is encroached
upon by the developing- leaves {cf. fig. vii.) it is not
at all clear that the periclinal wall in question is not
precociously formed in a cell which will later be involved in
the base of the leaf. Yet this single periclinal wall is
really the sole evidence obtainable from his figures of the
truth of Koch's view. Nevertheless the thorough method
of investigation inaugurated by Koch must sooner or
later settle the point. For the present we must admit
that though Hanstein's case is made out for a certain small
number of plants, the great majority of cases which have
been investigated must remain doubtful. Van Tiegfhem
(10, p. 776) does not definitely commit himself, though he
implies the suggestion that Hanstein's three initial layers
are universal in Phanerogams, though often not distinguish-
able owing to " enchevetrement" of the layers. But his
pupil Douliot (23) concluded that there was a single apical
cell in all Gymnosperms, and a plero- periblem in most

THE STELA R THEORY. 219

monocotyledons and some dicotyledons, while Koch takes
the view that there is a generalised meristem without
separate layers in Gymnosperms (21) and that only the
dermatogen is separate in most Angiosperms (22). So
that the "triple layer" theory of Hanstein and Van
Tieghem is accepted by neither of these two most recent
investigators as of general application, widely divergent as
are their views inter se. Considering that the theory of
the direction of ontogeny by the separation of different
kinds of somatic idioplasm is now generally discredited, it
is difficult to see what we gain by an adherence to the un-
proved hypothesis of the strict separation of the initial
layers, even if it is still a possible hypothesis.

In the root apex on the contrary the plerome is in the
great majority of cases sharply separated from the peri-
blem, but even this rule is not universal. The sharp
separation seems to be correlated both in root and stem
with the formation of a slender compact cylinder.

In Vascular Cryptogams, which nearly all possess either
a single apical cell or a single layer of initial cells giving
rise to the whole of the tissue of the axis, there is of course
no question of a separation, at the apex itself, of initial
layers.

The separation of the young cylinder behind the actual
growing point is quite a distinct question from its separation
at the apex. It is during the development of the cylinder
that we get, usually at least, a distinct limit between it and
the cortex which is often lost in the adult stem, and this is
a point of great importance.

Long before the stelar theory was originated, most of
the great anatomists, who laid the foundations of our know-
ledge of the histology of vascular plants, were practically
agreed on the generality of this early separation. This is
clearly shown in the terminology employed in designating
the various regions.

Thus Sanio (24), tracing from the apex the development
of the various tissues, showed that in many cases the young
pith first became separated from an outer zone, and that
in the latter the "thickening ring" (really corresponding to

220 SCIENCE PROGRESS.

Flot's "vascular meristem," i.e., the ring of tissue produc-
ing the bundle system plus the "external conjunctive":
shortly became differentiated from the peripheral zone or
young cortex. In other cases {Euonymus and Berberis),
the "thickening ring" appeared or began to appear before
the young pith became separated from the " outer zone".
Hanstein (25), as a consequence of his separation of the
primary meristem into Dermatogen, Periblem and Plerome,
makes the outer limit of the young cylinder, i.e., that
between periblem and plerome, of primary rank. Russow's
scheme (26), on the other hand, drawn from instances like
those of Sanio's first group,1 in which the young pith is the
first tissue to become apparent, divides the young tissue
produced by the general Protomeristem at the apex itself
into Endistem (Sanio's young pith) and Existent (Sanio's
" Aussenschicht "), the latter being separated into Mesistem
(Sanio's "thickening ring ") and Peristem or young cortex.
Thus the limit between "Mesistem" and "Peristem' is
reduced to secondary rank. But De Bary (14, pp. 395-6)
again sums up clearly in favour of the individuality of the
plerome.2 As a matter of fact the young pith often does

1 Russow placed Hanstein's best instances, for example, stem of Hip-
puris, and Roots, where there is a well-defined plerome at the apex itself,
under the separate heading of "Axes with Combined Bundles ".

2 The development of the pericycle is of great importance in this
connexion. Sanio (24) showed in several cases that what we now call the
pericycle was developed from the outer edge of the "thickening ring".
Schmitz (27) confirmed this view in Berberis and Menispermum. Van Tieg-
hem, however (5), based his conception of the pericycle entirely on the
ground of adult comparative anatomy. This is explicitly stated (p. 152) in
a remark he made at the close of a " Note sur le pericycle," read by
D'Arbaumont (28) to the Botanical Society of France. D'Arbaumont had
endeavoured to show that the sclerised portions of the pericycle, capping
the phloems of the stem bundles in dicotyledons, were developed in
common with the bundles themselves from the desmogen strands, and
were thus often separate from the interfascicular pericycle. His account
of the development of the continuous zone of fibres in Cucurbitacese and in
Berberis is different, and indicates differences in the origin of the pericycle
in various plants. It is unfortunate that no figures are given. Morot re-
plied (29) that even if the pericycle, or parts of it, were developed dif-
ferently in different plants, that made no difference to the validity or applica-

THE STELA R THEORY. 221

become recognisable in comparatively bulky apices (owing
to the early ceasing of longitudinal divisions, and the stretch-
ing of its cells), before the outer limit of the young cylinder
is defined. On the other hand, in the slender stems of
many water plants, Hanstein's scheme applies with dia-
grammatic precision, the outer limit of the cylinder being
clearly marked at the apex, before there is any sign of a
differentiation between pith and bundle ring. But these
differences of precocity in the development of the various
regions of the cylinder, depending, as they do, upon the
subsequent duration and size relations of the regions are
clearly of little importance to morphology. The important
fact which remains is the clear separation, slightly sooner,
or slightly later, of the young cylinder from the cortex, in
at any rate the vast majority of cases.

The separation thus made in development is, as a rule,
more or less clearly maintained in the adult stem, though
sometimes it is lost altogether. There is the possibility
of a complete loss of a visible boundary between cylinder
and cortex by the occurrence of irregular cell divisions in
the young pericycle and inner cortex, together with a
"shifting" (Verschiebung) of the original walls separating
the two ; unfortunately we do not know if this takes place
in some cases or not. But apart from such an occurrence
the distinction between cylinder and cortex, once made, is
always made, and the layer of cells which once abutted on
the young cylinder is still the phloeoterma, not merely
"theoretically," but in substance and in fact, however im-
possible it may become to distinguish it from the surround-
ing tissue.

It is these facts which form the real developmental basis
of the stelar theory.

The phenomena (supposing them to be established) of
real importance in the opposite sense, would be the occur-
rence of stems in which the external limit of the cylinder is
never clear, of stems, in a word, which never possess a

tion of the term. The further pursuit of the theoretical implications of this
statement would lead us into very deep waters, but it is clear that an ex-
tended comparative investigation of the origin of the pericycle is needed.

222 SCIENCE PROGRESS.

cylinder as such. While we could not admit that the stelar
doctrine applied to such stems, we should probably be
forced to the conclusion if their vascular system conformed in
all other respects to the monostelic type, that the plants in
question were derived from truly monostelic ancestors, whose
descendants had lost the limit between cortex and cylinder.

The Nymphseaceae, many of whose stems contain a
large number of "scattered" bundles, seem to furnish us
with examples of such plants. Caspary (27) states that
the bundles are here developed in centripetal order : this
would seem to indicate an analogy with those plants
(Piperaceae, Begoniacese, etc.), which possess a proper
bundle ring" and also younger bundles in the pith, rather
than with the monocotyledonous type. In at least one
member of the family, Victoria regia, which possesses
a particularly large number of these "scattered" bundles,
it appears that no well-defined cylinder is visible anywhere
in the stem.1 So here if anywhere we seem to have a real
case of "astely". We cannot, however, say the same
with certainty of any dicotyledonous stem with a single
ring of bundles. Nageli's observations (28) indeed led him
to the conclusion that the " cambial " strands were, as
a rule, developed in the midst of a homogeneous ground
tissue, but his conclusions, as we have seen, have been
negatived by most subsequent observers.

Turning to the vascular cryptogams we find that
whether monostelic or polystelic, the stele or steles can be
traced nearly up to the stem apex. The first formed peri-
clinal walls do not indeed necessarily mark the limit of
stelar tissue. They may cut off the pith, as in Equisetum
or mark the middle of the cortex, as in many roots, or
the outer limit of the ring of steles, as in many fern stems,
or of the single cylinder, as in the stolon of Nephrodium
(10, pp. 692 and 773-4). Clearly no special importance
can be attached to these walls, and we certainly can-
not use the fact that they mark off the pith in Equisetum,

1 1 owe this information to the kindness of a friend in telling me the
results of some unpublished observations.

THE STELAR THEORY. 223

as Van Tieghem does, to support the view that the genus
is really astelic. This argument depends on the assump-
tion that these walls always separate stelar from extra-
stelar tissue, which is not a fact, according to Van
Tieghem himself (10, p. 774), and further, a similar line of
reasoning would tend to show that the stems of a great
many dicotyledons, namely, those in which the pith is the
first tissue to be marked off, are also astelic.

SUMMARY OF RESULTS.

We have attempted in the foregoing pages to ex-
hibit, as clearly as possible, the bearing of well ascer-
tained facts of anatomy and development upon the stelar
theory as developed by Van Tieghem and his pupils. We
may appropriately conclude with an attempt to summarise
the results to which we are thus led.

We recognise in the central cylinder of the axes of the
great majority of the higher plants an anatomical region of
the first rank to be co-ordinated with the other great
anatomical regions, the cortex and the epidermis. The
central cylinder consists of vascular tissue (xylem and
phloem) and conjunctive tissue (typically parenchyma).
In the bulky typical * cylinder the vascular tissue is separ-
able into distinct strands corresponding with its centres (or
rather lines) of development, and giving to the cylinder a
radial symmetry ; the conjunctive of such a cylinder is
separable into distinct regions. Typically, also, the inner-
most layer of cortex, which abuts on the cylinder is dis-
tinguished by special characters.

Reduced central cylinders are found in various stem
structures, especially the thin stems of water plants. The
reduction acts first on the conjunctive, which may (though
rarely) quite disappear. This leads to the coalescence of
the strands of vascular tissue into a more or less solid
cylinder. Such a reduced cylinder is always sharply marked
of! from the cortex.

On the other hand we have stems in which it is im-
possible to separate the conjunctive from the adjacent

1 In Sach's sense of " most highly developed ".

224 SCIENCE PROGRESS.

cortical tissue. When this is the case in the adult, it is still
often possible to make the separation in the young stem.

Naming the central cylinder a stele, we call all stems
with a single cylinder monostelic.

Stems in which we cannot make the separation in any
part, and which are therefore not strictly monostelic, yet
conform more or less to the monostelic structure in other
respects, and are no doubt usually derived in descent from
the monostelic type.

Most Ferns and Selaginellas, and two genera of
Phanerogams, while showing a monostelic structure in
their hypocotyls, possess in their later formed stems more
than one cylinder, each comparable in structure to the single
stele of the hypocotyl. Such stems are known as polystelic.
The steles of a polystelic stem may, however, take on the
most various forms, and lose all the characters of the
original cylinder ; several may even coalesce to form a
structure indistinguishable from a single stele. As this, or
indeed the converse case of a non-stelar vascular strand
assuming the characters of a stele, may have happened in
descent without leaving any traces of the transformation, we
are not justified in asserting the homology of all steles or
denying homology between steles and non-stelar vascular
strands. Nevertheless the stele is undoubtedly a real and re-
latively stable type in the arrangement of vascular tissue, and
hence the name represents a real morphological conception.

The vascular tissue of a leaf is arranged in one or more
strands, each of which, bilaterally rather than radially
symmetrical, is called a schistostele or meristele, representing,
as it does, a part only of the stem cylinder. The meristele
of a petiole may, however, simulate a stele. In most poly-
stelic stems one or more of the stem steles directly enters
the petiole, and the branches maintain more or less of the
stelar character till near their endings in the lamina, where
they become indistinguishable from collateral bundles.

We are probably justified in supposing the monostelic
type to be primitive in vascular plants, and we may assume
the original stele to have been relatively simple. To the
increase in bulk of the stem and correlated increasing de-

THE STELA R THEORY. 225

mands for the supply of vascular tissue to leaves, the plant
either responded by increasing the bulk of the stele and
multiplying the number of its vascular strands, or by sub-
stituting a number of simple steles for the original single
one. This last occurrence happened once at least in the
Pteridophyta (probably more often), and more than once
among the Phanerogams.

The primordial stele is represented at the present day
by the single sharply defined stele of the embryo, which is
maintained in the root and hypocotyl, and which passes over
in the stem to one of the modern types of structure,
necessary to the various demands of the leafy shoot. The
arrangements at the apex of the latter are naturally adapted
to form the particular type of structure in question, and
can in no case be considered as representing an ancestral
form.

BIBLIOGRAPHY.

(1) Ph. van Tieghem. Recherches sur la symetrie de structure

des plantes vasculaires. Introduction, pp. 5-29. La Racine,
pp. 30-314. Annates des Sciences Naturelles, Botanique, 5
ser., tome xiii., 1870-71.

(2) Van Tieghem. Memoire sur les canaux secreteurs des

plantes. Ann. Set. Nat. Bot., 5 ser., tome xvi., 1872.

(3) FALKENBERG. VergleicJiende Untersuchnngen fiber d. Ban d.

der Vegctationsorgane d. Monocotyledonen. Stuttgart. 1876.

(4) MANGIN. Origine et Insertion des racines adventives. Ann.

Set. Nat. Bot., 6 ser., tome, xvi., 1882.

(5) VAN TIEGHEM. Sur quelques points de l'anatomie des Cucur-

bitacees, p. 277. Bulletin de la Societe" Botanique de Fratice,
tome xxix., 1882.

(6) Morot. Recherches sur le pericycle. Ann. Sci. Nat. Bot., 1884.

(7) Van Tieghem et Douliot. (a) Structure de la tige des

Primeveres nouvelles du Yun-nan, p. 95. (b) Groupement
des Primeveres d'apres la structure de leur tige, p. 126. (c)
Sur les tiges a plusieurs cylindres centraux, p. 213. Bull.
Soc. Bot. France, tome xxxiii., 1886.

(8) Van Tieghem et Douliot. Sur la polystelie. Ann. Sci.

Nat. Bot., 7 ser., tome iii., 1886.

(9) Leclerc du Sablon. Recherches sur la formation de la tige

des Fougeres. Ann. Sci. Nat. Bot., 7 ser,, tome xi., 1890.

(10) Van Tieghem. Traite de Botanique, 2ieme edition, 1888-91.

226 SCIENCE PROGRESS.

(il) FLOT. Recherches sur la zone perimedullaire. Ann. Sci.
Nat. Bot., 7 ser., tome xviii., 1893.

(12) VAN TlEGHEM. Remarques sur la structure de la tige des

Preles. Journal de Botauiqne,tome iv., p. 365, November, 1 890.

(13) Van TlEGHEM. Remarques sur la structure de la tige des Ophio-

glossees. Journ. de Bot., tome iv., p. 405, December, 1890.

(14) De Bary. Vergleichende Anatomie der Vegetationsorgane

der Gefasspflanzen, 1877 (English edition, 1884).

(15) STRASBURGER. Ueber den Bau und die Vorrichtungen der

Leitungsbahnen in den Pflanzen. Histologische Beitrage iii.,
1891.

(16) VAN TlEGHEM. Pericycle et Peridesme. Journ. de Bot.,

tome iv., p. 433, December, 1890

(17) Van TlEGHEM. Sur la structure primaire et les affinites des

Pins. Journ. de Bot., tome v., p. 265, etc., August, 1891.

(18) PAUL Zenetti. Das Leitungssystem im Stamm von

Osmunda regalis L. und dessen Uebergang in den Blattstiel.
Botanische Zeitung, April, 1895.

(19) Poikault. Recherches anatomiques sur les Cryptogames

vasculaires. Ann. Sci. Nat. Bot., 7 ser., tome xviii., 1893.

(20) D. H. Scott. Recent work on the Morphology of Tissues

in the Higher Plants. "Science PROGRESS," vol. i.,
August, 1894.

(21) L. KOCH. Ueber Bau und Wachsthum der Sprossspitze der

Phanerogamen. Pringsheinis Jahrbiicher f. zvissenschaftliche
Botanik, Bd. xxii., 1891.

(22) L.KOCH. Die vegetative Verzweigung der hoheren Gewachse.

Pr.J., Bd. xxv., 1893.

(23) DOULIOT. Recherches sur la croissance terminale de la tige

des Phanerogames. Ann. Sci. Nat. Bot., 7 ser., tome xi., 1890.

(24) San IO. Vergleichende Untersuchungen iiber die Zusam-

mensetzung des Holzkorpers. Bot. Zeit., 1863.

(25) Hanstein. Die Scheitelzellgruppe, 1868.

(26) Russow. Vergleichende Untersuchungen betreffend die

Histologic . . . der Leitbiindel-Kryptogamen, u. s. w.
Memoires de V academic imperiale des Sciences de St. Pcters-
bourgi 7 ser., tome xix., 1872.

(27) Schmitz. Ueber die Entwicklung d. Sprossspitze d. Phanero-

gamen. Halle. 1874.

(28) D'Arbaumont. Note sur le pericycle. Bull. Soc. Bot. de

France, tome xxxiii., p. 141, 1886.

(29) Morot. Reponse a la note de M. D'Arbaumont sur le

pericycle, ibid., p. 203.

(30) Nageli. Beitrage zur tvissenschaftliche Botanik, i., 1858.

A. G. Tansley.

THE PRESENT POSITION OF THE CELL-
THEORY.

PART II.

SINCE I have shown that protoplasm in the simplest
form in which it is known to us may not be regarded
as having an organisation in the sense in which that term
has any meaning, and since it is a waste of time to discuss
the use of the term when it has no meaning, we may more
profitably turn to the question whether protoplasm has a
structure, and if so, what kind of structure? Is it essenti-
ally the same in all the kinds of protoplasm which have
been studied, and is it of the same kind as the structure of
tissues and organs of metazoa or is it of a different kind ?
For it must be insisted upon that one may deny to proto-
plasm an organisation, in the proper sense of the term, and
yet one may consistently attribute to it a structure, even a
very complex structure. But that structure need not be
called an organisation, to do so is to confuse two clear
issues. It is worth while to emphasise this point, for some
people think it very inconsistent to affirm that protoplasm
has a complex structure and at the same time to deny that
it is organised.

I conceive that the view that protoplasm is composed of
granules, which are either biophors or secondary aggregates
of biophors, has been sufficiently refuted by Butschli's re-
searches on hyaline protoplasm already referred to. The
hyaline pseudopodia of Gromia show no trace of granules,
not because the granules are too small to be seen, for the
highest powers of the microscope reveal in the protoplasm,
at the moment of its protrusion to form a pseudopodium, a
structure which is not granular, namely, an alveolar structure,
and if granules were present they must necessarily be sought
for in the alveoli or in the alveolar walls. But they are to
be found in neither, so it may be affirmed that in the
simplest form of protoplasm there are no granules, a

circumstance which deprives the theory of biophors of much

16

228 SCIENCE PROGRESS.

of its weight. Of course it may be objected that the
alveolar walls and contents may be composed of biophors
so small as to defy detection ; such an objection must be
defended on theoretical grounds, and I will deal with it
presently ; just now I will confine myself to the considera-
tion of the visible structure of protoplasm.

After rejecting the granular theory we have a choice of
several others ; the fibrillar theory, the reticular theory, and
the alveolar theory of Biitschli. It would take too long for
me to examine these several theories in detail ; it has
already been done by Biitschli (loc. ciL, p. 177), and still
more recently by Yves Delage,1 if I were to undertake the
task I should only give a resume of their arguments.
For my own part I am strongly inclined in favour of Biit-
schli's " Wabenlehre ".

For some reason or other Biitschli's account of the
structure of protoplasm has not, to use a common ex-
pression, " caught on ". Possibly because it was published
at a time when men's minds were occupied with the more
alluring prospect offered by the granular theory of proto-
plasm, with all its delusive hopes of an explanation by means
of biophors, and primary organisation of the phenomena
of heredity, and of all the vital processes. Possibly also
because Biitschli himself pushed the analogy between micro-
scopic foams and protoplasmic structure too far. But if
his theoretical considerations are put aside, there is a great
deal to be said for his fundamental views. The alveolar
structure which he describes may be demonstrated in many
various forms of protoplasm. It is particularly obvious in
Pelomyxa, in which form the larger vacuoles serve admir-
ably as a contrast between the finer alveolar structure which
he claims to be common to all protoplasm and the grosser
vacuolar structure which is often mistaken for it. I have
myself identified the alveolar structure in a considerable
variety of protozoa, and in a number of tissue cells, and I
have succeeded in making Biitschli's artificial amoebae, and am

1 Yves Delage, La Structure du Protoplasma et les Theories sur
V Heredite et les grands problems de la Biologie generate. Paris : C.
Reinevald et Cie, 1895.

THE PRESENT POSITION OF CELL-THEORY. 229

convinced of the close analogy in structure between the
artifact and the natural product. The resemblance between
the two is exact, and it is astonishing. The optical char-
acters of the artificial product are explained, on physical
grounds, as the outcome of a certain structure, namely, an
alveolar structure. The identical optical characters of pro-
toplasm may surely be explained on the same grounds. It
is not pushing analogy too far to say that identical optical
characters are the result of identity of structure. The
analogy is somewhat strained when it is sought to prove
that the identity of the streaming movements in the arti-
ficial product with those in protoplasm are attributable to
the same physical causes. The chemical constitution of
the. two bodies is so different that the phenomena observed
might be regarded as secondary. Nor is the identity
absolute, for Biitschli himself points out that the induced
currents in the surrounding medium take place in the re-
verse sense in an amoeba to what they do in the case of
the microscopic foam. I cannot think that the criticism of O.
Hertwig invalidates Biitschli's theory seriously. Hertwig
says that lamellae of oil consist of a fluid which is not
miscible with water. If the comparison between the
structure of an emulsion and the structure of protoplasm
depends on something more than a superficial resemblance,
then the lamellae of plasma which are compared with the
lamellae of oil must consist of a solution of albumen
or of a fluid albumen. But a solution of albumen is
miscible with water, and therefore it would mix with the
contents of the alveoli : emulsions of albumen must be formed
with air, not with water. To this Biitschli answered that
the framework of plasma consists of a fluid composed of a
combination of an albumen and a fatty acid, which was
therefore not miscible in water. Another obvious answer
is that living plasma is not a simple albuminous solution,
for if it were most protozoa could not exist, they would
immediately dissolve in the water in which they live.
Whether a fatty acid exists in combination with the plasma
or not, there is something in the constitution of living-
plasma which differentiates it from albumen, for it does not

23o SCIENCE PROGRESS.

dissolve in water ; dead plasma on the other hand becomes
albumen and dissolves speedily. What that something is
I do not venture to suggest ; could we ascertain what it is,
no doubt we should have discovered the solution to the
riddle of life. Hertwig says that the structural elements of
protoplasm, be they filaments, or reticular, or lamellae, or
alveoli, or granules, or what else, have a fixed state of
aggregation. Protoplasm is no mixture of two immiscible
substances such as water and oil, but consists of a union of
fixed organic material particles with abundant water. This
is but a verbal statement of the facts and is no explanation,
but he adopts later on {Joe. tit., p. 49) Nageli's micellar
theory as an explanation. No doubt it is the best explana-
tion possible, but it again does not give more than a verbal
explanation of the remarkable and fundamental phenomenon
that protoplasm, be its structure what it may, does not when
alive dissolve in water, but when dead it becomes some-
thing else which readily dissolves, provided of course that it
is not killed by means which coagulate the albumens into
which it is converted at death.

I shall recur again to the micellar theory, for the pre-
sent purpose it is sufficient to say that it is not inconsistent
with Biitschli's " Wabenlehre,"1 and might even be pressed
into service to explain why the plasma does not mix with
the watery alveolar contents without the necessity of calling
fatty acids to aid.

Supported by these considerations, and by a considerable
mass of objective evidence, I venture to think that Btitschli

1 Biitschli criticises the micellar theory and the analogous theory of
"inotagmas" put forth by Engelmann. He does not accept either, but
does not give in their place any theory of the ultimate compositions of the
substances which form the alveolar framework and contents, except that
(p. 309) he says, " a series of reflections . . . led me to suppose . . . that
the chemical basis of the framework substance must be formed by a body
which has arisen from a combination of albuminoid and fatty acid mole-
cules." Such a combination must mean the formation of a chemical unit
of a higher order than the molecules which enter into its composition, and
for my purposes such a chemical unit is a micella. In this limited sense
the acceptance of a micellar structure is not incongruous with the " Wa-
benlehre ".

THE PRESENT POSITION OF CELL-THEORY. 231

has given a true account of the minute structure of proto-
plasm, so far as it can at present be determined by optical
means. And I even venture to prophecy that when the
history of the biological work of this half century comes to
be written some half century hence, the theories of biophors
and plasomes and the such like will have merely a historical
interest, whilst the work of Biitschli will be regarded as the
most sagacious and far-sighted contribution of our time to
this momentous question. In saying this I do not wish
to declare my adhesion to the more theoretical part of
Biitschlis work, but only to his account of the microscopic
structure of protoplasm.

Even if one were to accept his explanation of the
streaming movements there would remain all the other
phenomena of life to be accounted for, and they are inex-
plicable on the visible structure of protoplasm, even if it be
an alveolar structure.

Underlying the visible structure then there must be an
invisible structure, which is the cause of the phenomena.
This admission once made, the claims of the rival theories
of biophors, plasomes, plastidules and what not, again press
themselves on our attention. Now it is to be remarked
that the most cautious and thoughtful theorists do not claim
that their hypothetical units are an explanation of life.
Weismann categorically denies that his theory of the germ
plasm is a theory of life, it is only a theory of heredity, but
he goes so far as to suggest that a workable explanation of
the more complicated vital phenomena may be the surest
indication of the path which will lead to an explanation of
the more simple (loc. ciL, p. 21).

Others, however, are not so cautious, and in any case
there is this feature common to all, that they aver on the
one hand that vital processes are so complicated that they
cannot be explained by a physico-chemical theory of the
constitution of protoplasm, and that therefore we must
assume the existence of ultimate vital units or biophors :
on the other hand, after endowing these biophors with all
the attributes of life, they say that they have a comparatively
simple molecular constitution upon which the phenomena

232 SCIENCE PROGRESS.

which they exhibit depend. In fact they describe essenti-
ally similar functions in biophors and in cells, but they
allow a physico-chemical explanation in one case and
disallow it in the other. This contradiction has been
noticed by others, and it has never been satisfactorily
explained away. Whitman draws attention to it, and
observes that no one, as far as he knows, has looked upon
the unit as anything more than the seat of the mystery.
This is true, but it is no reason for putting" the mystery in
a small bag instead of a big one. He defends the theories
of smaller units, however, by saying that they have ex-
tended our knowledge of organic mechanism {Joe. cit.,
prefatory note, p. vi.). This again I believe to be true,
but not quite in the sense in which Whitman apparently
means it to be. The theories of minute independent vital
units have, I believe, led many on the wrong track as
regards vital mechanism ; the attacks on such theories are
leading to a considerable extension of our knowledge in
this direction. The ultimate vital units confessedly do not
remove the mystery ; ultimately the explanation of life
must be a chemico-physical one ; there is no alternative
but a vitalistic theory, and this is not admissible in science.
The strongest ground, viz., the granular hypothesis, for
assuming the presence of vital units is removed by the
observed constitution of hyaline protoplasm, and finally
none of the assumed aggregates of units which are admitted
to be visible, are identified with various sorts of granules
and considered to constitute units of a higher order, have
ever been shown to be capable of leading an independent
existence.

On the other hand there is a oeneral consensus of
opinion that protoplasm is not a simple organic compound.
Its unit is not the molecule, but an aggregate of molecules
forming a unit of a higher order to which the molecule
stands in the same relation as the atom does to the mole-
cule. It is also admitted that these molecular aggregates
may exist in many different kinds in protoplasm. Such a
conception is absolutely necessary for the explanation of
the most simple properties of organic bodies, for example,

THE PRESENT POSITION OF CELL-THEORY. 233

their optical properties and the imbibition of water. But it
is a physico-chemical conception, and the molecular aggre-
gate need not and should not be endowed with independent
vital powers. Such a molecular aggregate is the micella.
In accepting the micella one may attribute any amount of
complexity to protoplasmic structure without for a moment
admitting that it is a cono-eries of elementary organisms.
Nor need we admit all the theories which Nageli has tried
to establish as the necessary consequences of the assumption
that there are such things as combinations of polyatomic
molecules into groups of a higher order. As I have already
said, it was pointed out by von Sachs that even in the
region of pure chemistry it is necessary to assume that polya-
tomic molecules are grouped into closer molecular unions,
thus giving rise to chemical properties which did not belong-
to the individual molecules. But in the region of pure
chemistry such a grouping is not called an organisation,
nor is there any reason why it should be called an organisa-
tion in the present case. Let us be perfectly definite and
say that by a micella we mean a combination of polyatomic
molecules into closer union to form a group ; nothing more,
except in so far as we may reason on chemico-physical
grounds as to the behaviour of such groups and their
relations inter se. For instance (I am quoting from O.
Hertwig's summary of this part of the micellar theory) :
"The micellae exert an attraction both on water and on one
another, whereby the phenomena of swelling may be ex-
explained. In a dry organic body the micellae lie close to
one another, separated only by exiguous envelopes of
water : these latter enlarge considerably during imbibition,
since the attractive forces between the micellae and water
are at first greater than between the micellae themselves.
The micellae are separated from one another by the imbibed
water as it were by a wedge ; but an organised body does not
arrive at a condition of solution, since the attraction of the
micellae for water diminishes in the course of their separa-
tion from one another, at a greater rate than the attraction
of the micellae for one another, and therefore, when the
watery envelopes have attained a certain size, a condition

234 SCIENCE PROGRESS.

of equilibrium, the limit of imbibition is reached." And
also: "Since particles of water may be held fast on the
surfaces of the micellae by molecular attraction, so also
other matters (lime and siliceous salts, colouring matters,
gelatin compounds, etc.) may be deposited on them after
they have been taken into the organic body in a state of
solution ". So far as my physical knowledge enables me to
form a judgment, attributes such as these may justifiably be
ascribed to micellse on purely physical grounds and their
importance can hardly be overestimated, since the last
passage quoted affords a hint as to the nature of the essen-
tially vital process of assimilation. It is not my business
now to develop a complete theory ; I doubt indeed whether
a complete theory is possible in the present state of our
knowledge. I have done sufficient for present purposes if
I have succeeded in indicating what ideas we may justifiably
hold on the subject of protoplasmic structure, and I believe
that I have given some good grounds for justification of the
views that ; (i) the ultimate visible structure of protoplasm
is an alveolar structure ; (2) that the invisible structure of
protoplasm is a "micellar" structure in the sense defined
above.

But before I proceed I must enter a caveat against
being considered as an adherent of the micellar theory of
Nageli. I cannot enter here into my reasons, but I may
say that the further theories which Nageli assumes to
be the necessary consequences of the existence of micellae,
do not appear to me to be necessary consequences at all ;
indeed I part company with him at once when I express my
conviction that the hypothesis of a micellar structure is
compatible with the alveolar structure described by
Butschli.1

1 Since the above argument was first written out the work of Yves
Delage has come into my hands. It is most gratifying to find that the
opinions of so distinguished an author accord so exactly with my own. The
reader who finds my argument involved and laborious may turn with profit
to Delage's book, in which he will find a lucidity of expression and a
precision in argument which I can only envy without hoping to imitate. It
is worth while quoting the following passages here: "On peut accorder

THE PRESENT POSITION OF CELL-THEORY. 235

I may now anticipate the objection which is certain to
be raised that the visible and invisible structure which I
assign to protoplasm is utterly inadequate to explain the
phenomena of life. It is inadequate and it is intended to
be inadequate. Were I to pretend that it is adequate I
should be running counter to all the lessons taught by our
experience of living things. The structure which I have
assigned to protoplasm applies particularly to that simplest
known form of it which we rarely meet with, but which we
do meet with in exceptional cases, for instance in the pseudo-
podia of Gromia dujardini. But separate a protoplasmic
corpuscle formed by the thickenings of the thread-like pseu-
dopodia of this species from the rest of the animal ; the cor-
puscle separated is not any longer capable of an indepen-
dent existence, it soon perishes, it has all the structure
which I have described, but it is not capable of in-
dependent life. Clearly then life is not the outcome of this
structure, though the structure may play its part, and no
unimportant part in the life processes.

When I have been speaking of protoplasm I have
obviously been confining my attention to that form of it
which is now generally distinguished under the name of
Cytoplasm. Cytoplasm taken by itself is not living matter
in the sense that it is capable by itself of maintaining an
independent existence. The experiments of Nussbaum,1 of
A. Gruber and Verworn, confirmed by other observers, have

a l'auteur (Nageli) ses Micelles. Leur constitution, leurs proprietes n'ont
rien que de tres admissible. Bien que leur mode de generation ne soit
guere probable, il n'y a aucune raison positive pour le repousser. Mais
l'arrangement des micelles et la structure de l'idioplasma sont invraisem-
blables au plus haut point. Nous avons demontre, au cours de notre
expose, que cet arrangement n'est pas de tout, com me l'auteur l'avance, le
resultat necessaire du seul jeu des forces moleculaires initiates ce n'est
qu'a grand renfort d' hypotheses etagees l'un sur les autres qu'il arrive a
faire disposer les Micelles en Files, les Files en Faisceaux, les Faisceaux en
Cordons et les Cordons en un Reseau repandu dans tout l'organisme."

1 It was Nussbaum who first introduced the method of dividing in-
fusoria by artificial means, and the credit of having devised this very useful
class of experiment belongs to him. In my previous article I inadvertently
assign it to Gruber.

236 SCIENCE PROGRESS.

shown that pieces of cytoplasm cut off from the remainder
of a protozoon are incapable of maintaining life and soon
perish. If, on the other hand, a fragment of cytoplasm
similarly cut off contains nuclear matter, it is shown to con-
tain the attributes necessary to life, for the fragment does
not perish but reconstitutes itself and becomes an inde-
dependent living being. The converse also holds good.
A nucleus or a fragment of a nucleus isolated from a
protozoon, is incapable of life and perishes. But a nucleus
or a fragment of a nucleus in conjunction with a fragment
of cytoplasm is capable of life and constitutes an indepen-
dent living being. The reasonable inference is that cyto-
plasm plus nuclear matter is indispensable for the per-
formance of vital functions.

Now cytoplasm plus nuclear matter constitutes a cell.

I have elsewhere discussed at some length the definition
of a cell,1 and I have defined it as a corpuscle of protoplasm
which contains nuclein. In the present state of our know-
ledge this definition seems the only one possible. The cell
then consists of two essential substances, cytoplasm and a
substance which is different from cytoplasm, both structurally
and in chemical constitution, namely, nuclein. In a great
majority of cells other substances are present which are
different from both of these. Such substances are the
centrosomes, that modification of cytoplasm which is called
archoplasm, amylum and aleurone grains and so forth. As
far as we know, however, these substances are not essential
to life, but are secondary products characteristic of dif-
ferentiated cells. Recent researches on the structure of
Bacteria and Oscillaria justify the assertion that cells exist
in which these substances are absent. We know next to
nothing about the presence or absence of centrosomes and
archoplasm in the Protozoa, and it may be that further
investigation will lead us to the conviction that these two
are as essential to the life of these forms as the presence of
cytoplasm and nuclein. Maybe not ; in any case it does

1 Quarterly Journal of Microscopical Science, vol. xxxviii., p. 137,
1895.

THE PRESENT POSITION OF CELL-THEORY. 237

not matter for present purposes. It is sufficient to know
that two substances, cytoplasm and nuclein, must be brought
together or life cannot exist, and that it does exist in
organisms in which these substances, and these only, can be
detected, viz., in Bacteria. This statement may appear some-
what hazardous, seeing that the presence of a nucleus is
denied in several living beings, in bacteria, for instance, and
in yeast. A nucleus in the sense of a centralised body is
certainly absent in these and in many other forms, but
Biitschli has demonstrated the presence of nuclein in
Oscillaria in Bacterium lineola. As for Saccharomyces it
undoubtedly contains nuclein, for Raum has prepared it
from yeast cells, and the most recent observer, Macallum,1
is of the opinion that the nuclein is distributed through the
cytoplasm but also aggregated in the so-called granules of
Raum.

The statement therefore can scarcely be called hazardous,
and it is really warranted by the facts at our disposal, for
the more carefully that researches are made, and the more
delicate the methods of investigations employed, the more
is the presence of nuclein demonstrated where it was not
previously supposed to exist.

Macallum's paper, by the way, is of great interest, for he
shows that nuclein is essentially the iron-holding substance
in cells. Knowing as we do the close connection there is
between the presence of iron and the due performance of
the vital processes, this observation opens up a fruitful
source of inquiry as to the dependence of life on chemical
processes.

Throughout this argument I have tried to stick to the
rule of drawing legitimate inferences from observed facts
without wandering into the obscure regions of hypothesis.
If I have been successful and have fairly stated the facts,
and have drawn legitimate inferences, the conclusion which
I come to must be admitted to be of considerable weight.

1 A. B. Macallum, "On the distribution of Assimilated Iron Com-
pounds, other than Haemoglobin and Haematins, in Animal and Vegetable
Cells," Quart. Jour. Mir. Sri., vol. xxxviii., pp. 175-274, 1895.

238 SCIENCE PROGRESS.

The conclusion is this : that life is possible only when two
(or more) substances of complex chemical constitution are
brought together, and that when these two (or more) substances
ai'e brought together we have before us a cell. The cell there-
fore is the vital unit /car' e^o^V. The component parts of
the cell are not vital units, for by themselves they are in-
capable of life; they are the auxiliaries, the indispensable
auxiliaries of life, but they are not themselves living.

This is not a theory of life, and it does not pretend to
be one. It is the generalisation which the facts seem to
warrant, and if it be true, as I believe it must be true, it is
entirely inconsistent with the whole group of theories based
upon hypothetical biophors, gemmules, plasomes, physio-
logical units, plastidules et hoc genus omne. Those theories
are false. And the cell theory is not inadequate, but it is
the only theory which our knowledge of structure and of
life processes permits us to adopt, at least if we confine
ourselves to that part of it which is essential, namely, that
there is one general principle for the formation all tissues,
animal and vegetable, and that principle is the formation of
cells.

Cells are the ultimate vital units, though they are not
the ultimate structural units ; they are the Lebenstrager, or
biophors, and there are no living individuals lower than
cells.

As I have made an effort to stick to facts and have
slighted hypotheses, I shall doubtless incur the profound
contempt of those superior persons who find no mental
repose in things which can be clearly apprehended, but
must leave the material support of earth and seek for rest on
the unsubstantial pillows of cloudland. They will have
abundant scope for exercising their contempt, for my con-
clusion explains nothing, and gives no clue to the problems
of heredity.

As I have said in the earlier part of this essay, I have
no intention to discuss here the complicated problems which
are involved in the question of heredity. I take my stand
on the position from which I started, namely, that if minute

THE PRESENT POSITION OF CELL-THEORY. 239

vital elements occur at all, those same elements which make
life possible and control assimilation and growth must also
be the agents in bringing about the phenomena of heredity.
I have shown that minute vital elements smaller than
cells cannot be believed to exist, and it is clear that the
phenomena of heredity cannot be explained by things
which have no existence. This is a sufficient answer to
those who would say that the phenomena of heredity are
such that we must make use of a hypothesis of minute
vital elements, which are at once the bearers of the vital
qualities and the bearers of the heritable qualities (the his-
toric properties if the expression is preferred) of protoplasm.
It is not true that a theory of heredity is impossible unless
such elements are postulated. Delage has brought forward
a theory of heredity which discards altogether the use of
hypothetical biophors. I pass no criticism on his theory,
favourable or unfavourable, but call attention to it merely
for the purpose of showing that a theory without biophors
is possible. It is no argument to say that the theories
based on ultimate vital units have largely extended our
knowledge of heredity. The Ptolemaic system of astronomy
largely extended men's knowledge of the movements of
the heavenly bodies, but it was not on that account a true
theory.

Moreover, it will be hardly fair to twit me with the
fact that I renounce, for the present, an attempt to explain
the most complicated manifestations of life, for this is only
an essay, and makes no pretence to be the development of
a doctrine.

It is not my present intention to frame hypotheses, not
because I undervalue the use of hypothesis, but because I
regard the first necessary step to be the formation of ideas
appropriate to the facts.

Dr. Whitman has recently written quite a nice little
lecture on the subject of fact and theory, and has directed
it against myself in particular, winding up with a trenchant
paragraph to the effect that the claim to a monopoly of
fact reflects an arrogance which seems to be epidemic.
This homily is fortified by quotations from von Baer,

240 SCIENCE PROGRESS.

Goethe, Huxley and Whewell. Now I never claimed
a monopoly of fact, but that facts should receive a due
share of recognition. Mutual service, as Whitman says,
is the principle which ties theory and fact together ; quite
so, but when theory runs altogether away from fact, the
mutual service is wanting. Fact is a slow servitor, and
drags heavily on the impatient feet of theory. The quota-
tions from Goethe and Huxley do not lend support to the
practice of making hypotheses, rather the contrary. "Ex-
perience. Reflection, Inference " is an excellent motto, but
inference does not mean making hypotheses, nor yet does
the necessary process of generalisation and classification
which Huxley recommends. The passage quoted from the
last-named author condemns the mere cataloguing of facts
under the name of Science, but it does not countenance the
reckless use of theory. As for Whewell's aphorism, let me
commend to Whitman a study of what that author says
with regard to the failure of the Greek schools of philo-
sophy. They did not fail, he says, because they neglected
facts ; the Aristotelian school may be held to have surpassed
the moderns in its appreciation of the value of facts. The
Greeks certainly did not fail for want of boldness in theor-
ising, nor for want of acuteness, of ingenuity and power of
close and distinct reasoning. Nevertheless with all help
from the twin-service of fact and theory their philosophy
was a failure, and why ? Because, as Whewell points out,
their ideas were not distinct and appropriate to the facts.
May not the same thing be said of many of the theories of
cell life and of heredity which have been so much in vogue
in the last few years ? It was my object when I wrote on
Epigenesis and Evolution to show that some ideas then
current, were not appropriate to the facts ; it has been my
object in the present essay to show that certain theories on
cell life, beautifully constructed and ingeniously defended as
they have been, are not appropriate to the facts. I am far from
undervaluing the use of theory, and when I took occasion
before, as I have done again now, to emphasise the impor-
tance of attention to fact, I was not quite so ignorant nor
so arrogant as Whitman supposed. The motto of Goethe

THE PRESENT POSITION OF CELL-THEORY. 241

might well have been reversed for the adornment of the
title pages of some works of the last twenty years. " Theory,
reflection, experience," the last named to be fitted in as best
it might.

Since the above passages were first written the great
work of Yves Delage has came into my hands. Mine is
not the only voice crying out in the great wilderness of
theories. This new voice, however, is far greater and
more powerful than mine. The reader who may be uncon-
vinced by my clumsy argumentation should turn to the
pages of Delage. For clear and candid exposition, trenchant
criticism, and rigorous exposure of defects of reasoning,
they are unsurpassed. Now that this part of my work is
ended I feel that it need never have been begun, for all
that I have had to say has been said in greater detail and
with much greater force by Delage.

FERNS, APOSPOROUS AND APOGAMOUS.

THE normal life cycle of ferns, owing to the micro-
scopic character of their reproductive apparatus,
long baffled the comprehension of botanists. But some
half a century ago, starting with the observations of Naegeli
and Suminski and culminating in those of Hofmeister,
the whole course of their ontogeny has been cleared up.
The fern plant, as ordinarily so-called, produces on the
back of its leaves or fronds, countless numbers of spores,
which are formed within minute capsules or sporangia.
When these spores germinate they give rise, not to a new
fern plant, but to a leaf-like scale — the Prothallus. Upon
the lower surface of this the sexual organs arise, and within
them the sexual cells themselves are differentiated, and as the
result of the fertilisation of one of the female cells or
oospheres, by the male cell or antherozoid, a new fern plant
arises. Thus in normal cases a regular alternation of a
sexual with a sexless generation is seen. But although
this is the course followed by the vast majority of the ferns
which have been hitherto investigated, it is not the only
one open to the plants. Thus Prof. Farlow in 1874 dis-
covered that the formation of the sporophore (fern plant)
generation might arise directly from the oophore (prothallus)
generation, without the intervention of sexual organs, by a
process resembling ordinary budding. De Bary, who
followed the matter further, found that several ferns other
than that examined by Farlow reproduced themselves in
the same fashion, to which phenomenon the name of
Apogamy was given, the marriage link being eliminated.
Curiously enough De Bary found that a variety of one of
our most vigorous British ferns reproduced itself constantly
in this asexual manner, though the common form exhibited
no abnormality in this respect. Recently, however, L.
Kny,1 pursuing these investigations further, has found the

1 Entivickehing von Aspidium Filix mas. Sk'., i Theil., L. Kny,
Berlin.

FERNS, APOSPOROUS AND APOGAMOUS. 243

normal form to reproduce itself in both ways, and since his
asexual examples occurred in thickly-sown pots, it would
appear to be due to some extent to a starved condition
induced by overcrowding, which checks the formation of
the archegonia, and leads to the simple budding in their
place. In all these instances the young plants are en-
gendered upon precisely the same spots on the prothallus
as the sexual one would occupy, and as their development
and appearance are identical, it is only by preliminary
watching that their apogamic origin can be determined.

A case of Apogamy (or rather two cases), however,
recently occurred in a sowing of my own, which is quite
distinct from any I have seen described. A sowing of a
plumose variety of Athyrium jilix foemina failed almost
entirely, only two or three prothalli surviving. One of
these after growing very large, nearly half an inch across,
remained perfectly dormant the whole of the summer ;
early in the autumn, however, the edge of the prothallus
began to grow out and upwards in two places, and eventu-
ally two slightly curved horns,1 each about one quarter
inch long, developed perpendicularly, one on each side of
the indentation or sinus common to most prothalli. Later
on, at a short distance from each tip, a small whitish bulbil
appeared and these increased in size until the circination of
several fronds was plainly visible, a small crown or caudex
being developed. No roots, however, were emitted, and
the two little plants, both, be it remarked, identically
situated and very like in form, were evidently supported by
the prothallic root-hairs, though by this time most of the
prothallus was brown and dead. Subsequently I placed a
piece of loam in contact, and into this both plants rooted
and fronds were sent up, the first of which had no less than
ten pinnate divisions on either side. It was thus, it will be
seen, very different from the usually simple primary fronds
produced either sexually or apogamously heretofore. Later
on still, noticing that the tips of the horns were showing
signs of dilating, I cut these off with a razor and laid them

1 Gard. Chronicle, 10th Nov., 1894.
17

244 SCIENCE PROGRESS.

down, two apparently normal and full-sized prothalli being
the present result. In this case it will be noted that both
plants were far removed from the usual site of reproduction,
and both in this respect and in their vigorous development
are differentiated from previously cited cases of apogamy.
The second case alluded to occurred on another prothallus
in the same pan, wherein the bulbil developed likewise
upon a horn-like excrescence, but on the centre of the upper
surface of the prothallus. This bulbil has developed into
what is so far a very weakly plant of a different type to the
others, but otherwise presenting no special feature.

Until 1884 the Prothallus had always been regarded as
necessarily the offspring of the spore, but in the autumn of
1883 a presumed barren variety of Athyrium jilix fcemina
{var. C/arisstma) was sent me for examination. For
twenty years this plant had been observed to produce an
immense number of apparent sori, but no spores were
ripened or shed, and no offspring had consequently been
raised. Some previous observations on dorsal bulbils, i.e.,
bulbils associated with the spore heaps in this same
species, led me to the opinion that these apparent sori,
which consisted of green pear-shaped masses instead of the
capsules proper to spores, did not represent bulbils, but
some abnormality in the development of the sporangia.
To test this I laid down portions of the fronds, and
to my intense surprise these pearshaped bodies com-
menced at once to grow into prothalli, their tips dilating
and spreading, while root-hairs and subsequently both
archegonia and antheridia appeared in abundance. I at
once gave a note of my observations at the Linnean
Society x as demonstrating the development of the prothallus
without the agency of the spore. The following season,
pursuing my culture, I was able to exhibit a number of
plants and such material as satisfied the society of the
facts put forward.2 Prof. F. O. Bower 3 then undertook

1 " Observations on a Singular Mode of Development in the Lady Fern
{Athyrium filix fosmina)" Linn. Soc. Journal Botany, vol xxi., p. 354-7.

2 " Further notes on ditto,'' ibid., vol. xxi., pp. 358-60.

3 " On Apospory in Ferns (with special reference to Mr. Charles T.
Druery's observations),'' F. O. Bower, ibid., vol. xxi., pp. 360-68.

FERNS, APOSPOROUS AND APOGAMOUS. 245

the further investigation of the case, and found that the
development of the sorus or spore heap went as far as the
formation of the stalk of the sporangium or spore capsule,
but at that stage it stopped and a vegetative growth set in
to form the clusters of pear or club-shaped bodies which
eventually went through the normal evolution of prothalli
and sexual plants. Mr. G. B. Wollaston followed by
providing material from a variety of Polystichum angulare
in his possession, wherein the elimination of the spore and
the entire soral apparatus was so complete that the prothalli
were developed from the slender-pointed tips of the ultimate
divisions of the fern-frond. Padley, P. ang. var pule her rinmm
was the plant in question, and as it chanced that several
other varieties of the same type existed, though found at
widely sundered spots in England, it resulted that Dr.
F. W. Stansfield and myself found the same character in
two of them. Prof. Bower further observed that soral
apospory, i.e., the form first noted, was also present on
Padley's plants, and this too we, Dr. Stansfield and my-
self, confirmed in the others. We have in these four
examples, and in the genus Polystichum especially, ample
proof that the spore is not an essential preliminary to
the existence of the Prothallus, but that the latter may
be developed direct from the tissues of the Sporophore,
precisely as this latter in Apogamy may be developed
direct from those of the oophore.1 Curiously enough
the next case which came before the writer's notice
was an aposporous seedling of the same variety of Lastrea
(Aspidium) determined by De Bary as being persistently
apogamous, viz., Lastrea pseudo ?nas var. cristata. This
case was distinct from previous ones as it was a young
plant and not an adult, which produced the prothalli. The
tip of the second frond evolved from the prothallus (the
first was eaten off and was not seen) bore a prothallus of
the normal form. Subsequently this and the succeeding

1 Professor F. O. Bower subsequently prepared an exhaustive mono-
graph "On Apospory and Allied Phenomena". Linnean Transactions,
vol. ii., part 14, July, 1887, to which reference should be made for details
of the preceding cases.

246 SCIENCE PROGRESS.

frond became covered with prothalli developed not merely
from the edges, but also from the upper surface, and being-
pegged down produced a number of plants, but whether
apogamously or not I cannot say, though from De Bary's
observations, they should be so. It is worthy of remark
that in some of these youngsters, the line between the two
generations of sporophore and oophore was so vague that
the primary fronds were simply stalked prothalli, the next
frond half one and half the other, while the fourth or
fifth had quite outgrown the tendency and were of the
typical varietal form. This plant was exhibited and de-
scribed at the Linnean Society, 3rd November, 1892.1 Of
the next two cases I observed, the first was an Athyrium
found in Lancashire and exhibited in 1893 at the meeting
of the Pteridological Society at Lancaster by Mr. Bolton
the finder. Immediately on seeing it I remarked, "How
very like Col. Jones's Clarissima," simultaneously with which
Mr. Bolton said, " It is strange, but it never ripens its
spores " ". Turning the frond over, the reason was clear,
it was perfectly white with aposporal excrescences. On
submitting these to culture they produce plants freely by
sexual action, but of two types, one very depauperate, mere
skeleton plants, and the other of the parental form with
occasional reversion towards the normal. In some of these
young plants the whitish excrescences are plentiful in
fronds only an inch or two high, and there are evident
signs of prothalloid growth at the tips of the segments as
well, pointing to apical apospory when the plants are more
developed. The next case occurs in a most unlikely species,
especially as apical apospory is in question. This is seen
in a variety of Scolopendrium vulgare (S. v. cri spurn
DrummondicB) which occurs in the wild state, like all the rest,
characterised by being frilled and crested, and having more-
over a finely fimbriated edge to the fronds. Visiting Mr.
Bolton to inspect the Athyrium last cited, I saw a fine plant of
this fern, and it immediately struck me that the tips of

lu Notes on an Aposporous Lastrea (Nephrodium)" Linn. Soc. Journal
Botany, vol. xxix., pp. 479-82.

FERNS, APOSPOROUS AND APOGAMOUS. 247

the fimbriate projections were remarkably translucent. I
obtained material, laid it down, and at once prothalli began
to develop vigorously from every point, so vigorously
indeed that a single tip has formed a mass of prothalli an
inch across which yielded at least a dozen plants of the
parental form.1

Dr. F. W. Stansfield has recently sent me prothalli
developed from a finely fimbriated form of Lastrea of
which the reputed parent is that already described, and in-
forms me that it is profusely aposporous though fairly de-
veloped in size.

By the various instances of this phenomenon so far
cited, we see that the normal life cycles of the ferns in
question have been successively shortened, first by the
elision of the spore and then by that of the whole soral
apparatus, while if we accept De Bary's observations as
establishing the constant apogamous reproduction of L.
pseudo mas cristata, in that case, it is shortened almost to
the utmost, the chain being simply sporophore, prothallus,
sporophore. Consistently indeed with the alternation of
generation the chain could not apparently be shorter since
the prothallus being eliminated we naturally come, or
seem to come, to simple bulbils, such as occur on many
ferns, Aspleniuvi bulbiferum for example. In the final
case, however, which I have to cite, we arrive at the
elimination even of the prothallus by substitution of the
frond itself as the oophore or egg-bearer, the archegonia
and antheridia being generated upon the frond without the
prior formation of a prothallus proper. In a small plant
of Scolopendrium vulgare recently sent me by Mr. E. J.
Lowe, and exhibited by me at the Linnean Society in
November last, although a definite axis of growth had been
formed and several fronds had arisen in the normal spiral
fashion around it, indicating that the prothallus stage had
been unmistakeably passed, each of these fronds bore a
thickened cushion at its tip upon which were seated both

1<lNote on Apospory in a form of Scolopendrium vulgare" etc., Linn.
Soc. Journal, vol. xxx., pp. 281-84.

248 SCIENCE PROGRESS.

antheridia and archegonia, accompanied by aerial roothairs,
the frond itself thus assuming the functions of the pro-
thallus. Mr. Lowe raised a number of similar plants on
the genesis of which he is preparing a paper which I will
not forestall ; but he informs me that in time they throw
off this aposporous character. Fronds which he has sent
me, and which I have laid down, have developed prothalli
all over their surface and at all terminals, but so far my
cultures are too recent to permit me to report the advent of
plants.

This completes the sketch of the cases which have
come under my immediate notice, but considering that, in-
cluding the first discovery, the phenomenon has been
observed in no less than nine instances in our limited num-
ber of British species, viz., Lastrea [Nephrodium) two, Athy-
rium filix fcemina two, Polys tic hum angular e three, and
Scolopendrium vulgare two ; it is only reasonable to ex-
pect that many undiscovered instances must occur in the
innumerable other species existent throughout the world.

Charles T. Druery.

Science progress*

No. 28.

June, 1896.

Vol. V.

THE GROWTH OF OUR KNOWLEDGE OF

HELIUM.

THE DISCOVERY OF THE LINE D3, 1868.

IN the year 1868, spectrum analysis was first utilised in
endeavouring" to unravel the message which was con-
veyed to us by a most interesting eclipse observed in India.
The diagrams will indicate the kind of record with which
we have to deal in studying these celestial hieroglyphics.
We are in one part dealing with the long waves of light,
the red ; we are in the other dealing with the shorter waves
of light, the blue. The work done in that eclipse is
indicated by the bright lines — the hieroglyphics — which,
when translated as they have been, describe for us the
chemical nature of the particular stuff in the sun, which
made him put on a blood-red appearance " on his getting
out of his eclipse ". Taking the notes in the light scale
which are lettered in the ordinary spectrum of sunlight, in
order that they may be easily recognised and remembered,
we learn the particular qualities of the light emitted by the
blood-red streak.

We have one quality represented by the line D, another
at C, and another at F. According to the diagram, one of
the lines is in the position of D. One observer said it was
"at D, or near D ".

Soon after this eclipse was observed in India, a method,

18

250

SCIENCE PROGRESS.

long before formulated, of studying the blood-red streak
surrounding the sun without waiting for an eclipse was
brought into operation.

By this method it was quite easy to make observations
whenever the sun was shining, perfectly free from any of
the difficulties attending the hurry and the worry and the
excitement of an eclipse, which lasts only a few seconds.

B C -D Ef F G

Fig. i. — Pogson's diagram of the spectra of the sun's surroundings in the
Eclipse of 1868. The bright lines seen are shown in the upper part
of the diagram ; the chief lines in the solar spectrum, red to the left,
blue to the right, are shown in the lower part.

A 1

BC

D Eb

F G

H

J

. 1

Ha

H/» Hr

BB

■

I

Fig. 2. — Summation of the observations of the spectrum of the
sun's surroundings in the Eclipse of 1868. (1) Solar
spectrum showing the position of the chief lines. (2)
Rayet's observations of bright lines. (3) Herschel's obser-
vations of bright lines. (4) Tennant's.

Further, as the method consists of throwing an image of
the sun, formed by a telescope, on to the slit of a spectro-
scope, so that the spectrum of the sun's edge and of the
sun's surroundings can be seen at the same time, exact
coincidence or want of coincidence between the bright and
dark lines can be at once determined. During an eclipse

THE GROWTH OF OUR KNOWLEDGE OF HELIUM. 251

this of course is not possible, as the ordinary spectrum of
the sun, with its tell-tale dark lines, is invisible because the
sun, as we ordinarily see it, is hidden by the moon.

Working, then, under such very favourable conditions, it
was seen that there was certainly a red line given by this lower

1

I

Fig. 3. — The exact coincidence of the red line with the dark line C.

part of the solar atmosphere coincident with the very im-
portant line in the solar spectrum which we call C.

Another part of the spectrum in the blue-green was
examined, and there again it was seen that the parts out-
side the sun gave us a bright line exactly in the position of

> ii 1 1 1 11 1 1 1 1 1 1 I ■

Fig. 4. — The exact coincidence of the blue-green line with the dark line F.

the obvious dark line in the solar spectrum which is called
F ; so that with regard to those two most important lines,
there was no doubt whatever that we were dealing with
the substance which produces these dark lines in the solar
spectrum.

252

SCIENCE PROGRESS.

Fig. 5 is a diagram of the yellow, or rather the orange,
part of the solar spectrum, showing two very important
lines, which are called the lines D, due to the metal sodium,
the investigation of which was just as important in solving
the celestial hieroglyphics we call spectral lines as the
Rosetta stone was important in settling the question of the
Egyptian ones.

Pogson, in referring to the eclipse of 1868, said that the
orange line was "at D, or near D ". We see from the

D1 D2

Fig. 5. — The want of coincidence of the orange line D3 with the dark

lines D1 and D2.

diagram (Fig. 5) that the new method indicated that "near
D " was the true definition. The line in this position in
the spectrum, unlike the other two lines which I have
indicated, has no connection at all with any of the dark
lines in the ordinary solar spectrum. We were therefore
perfectly justified in attaching considerable importance to
this divergence in the behaviour of this line, taking the
normal behaviour to be represented by the two strong lines
in the red and the blue-green. The new line was called
D3 to distinguish it from the sodium lines D1 and D2.

A considerable amount of work was done with regard
to the orange line. It was found that there was no sub-
stance in our laboratories which could produce it for us,
whereas in the case of the line D we simply had to burn
some sodium, or even common salt, in a flame to produce
it, and the other lines in the red and the blue-green were
easily made manifest by just enclosing hydrogen in a
vacuum tube, and passing an electric current through it,

THE GROWTH OF OUR KNOWLEDGE OF HELIUM. 253

or observing the spectrum of a spark in a stream of coal-
gas.

Now at the first blush it looked very much as if this
line was really due to the same element which produced
the others at C and F, and it was imagined that the reason
we did not see it in our laboratories was because it was a
line which required a very considerable thickness of hydro-
gen to render it visible. That was the first idea, and Dr.
Frankland and myself found that there was very consider-
able justification for this view, because a simple calculation
showed that the thickness of the solar atmosphere, which
was producing that orange line under the conditions which
enabled us to see it in our instruments by looking along the
edge of the sun, was something like 200,000 miles.

ABC
Fig. 6. — Changes of wave-length of the F hydrogen line when a solar
cyclone is observed. A, the change towards the red indicates the
retreating side of cyclone. C, the change towards the blue indicates
the advancing side. B, the whole cyclone is included in the width of
the slit, and both changes of wave-length are visible.

Hence, in order to get a final decision on this point,
there was nothing for it but to tackle the question from a
perfectly different point of view, and the different point of
view was this. The work had not gone on very long
before one found minute alterations in the positions of these
lines in the spectrum ; the orange line, for instance, might
sometimes be slightly on one side, and sometimes on the
other of its normal position. Further work showed that in
these so-called " changes of wave-length " we had a precious
means of determining the rate of movement of the gases
and vapours in the solar atmosphere.

Fig. 6 indicates how these changes of wave-lengths are

254 SCIENCE PROGRESS.

shown in the spectroscope. The lines are contorted in both
directions, and sometimes to a very considerable extent,
indicating wind movements on the sun, reaching and some-
times exceeding ioo miles a second.

We had here a means of determining whether the
orange line was produced by the same gases which gave the
red and blue lines, because if so, when we got any altera-
tion in the position of the red and blue lines, which always
worked together, we should get an equivalent alteration in
the position of the orange one.

I found that the orange line behaved quite differently
from either the red or the blue lines ; so then we knew that
we were not dealing with hydrogen ; hence we had to do
with an element which we could not get in our laboratories,
and therefore I took upon myself the responsibility of coin-
ing the word helium, in the first instance for laboratory
use.

This kind of work went on for a considerable time, and
what one found was, that very often in solar disturbances
we certainly were dealing with some of the lines of sub-
stances with which we are familiar on this earth ; but at the
same time it was very remarkable that when the records
came to be examined, as they ultimately were with infinite
care and skill, it was found that not only did we get this
line in the orange indicating an unknown element associated
with substances very well known, like magnesium, but that
there were many other unknown lines as well. Within a
few months of my first observations, several new lines about
which nothing was known were thus observed.

THE DISCOVERY OF OTHER UNKNOWN LINES, 1869.

The place of the orange line D3 I determined on
20th October, 1868. Among many other lines behaving
like it, two at wave-lengths 4923 and 5017 were discovered
in June, 1869, and afterwards another at 6677, while Pro-
fessor Young noted another in September, 1869, at 4471.
He wrote : —

" I desire to call special attention to 2581*5 [ = 4471 on

THE GROWTH OF OUR KNOWLEDGE OF HELIUM. 255

Kirchhoff's scale], the only one of my list, by the way,
which is not given on Mr. Lockyer's. This line, which was
conspicuous at the Eclipse of 1869, seems to be always
present in the spectrum of the chromosphere. . . . It has no
corresponding dark line in the ordinary solar spectrum, and
not improbably may be due to the same substance that
produces D3."

This same line was noted also by Lorenzoni and named
f. Another line at 4026 was added later by Professor
Young.

Fig. 7. — Tacchini's observations of two slight solar disturbances
showing the height to which the layers of the different gases
extend. Magnesium vapour is highest of all, and is furthest
extended ; next comes a gas of still unknown origin, indicated
by a line at 1474 of Kirchhoff's scale and so on.

Then with regard to solar disturbances. Let me refer
in detail to a diagram indicating some results arrived at by
the Italian observers. We are dealing with the spectro-
scopic record of two slight disturbances in a particular part
of the sun's atmosphere. The spectroscope tells us that in
that region there was a quantity of the vapour of magnesium
which is collected in that place. Then we find that another
substance, about which we again know nothing whatever,
is also visible in that region, and then we get the further
fact that in those particular disturbances we get four other
spectral lines indicated as being disturbed, and of those four
lines we only know about one.

256 SCIENCE PROGRESS.

In that way it very soon became perfectly clear to those
who were working at the sun, that in all these disturbances,
or at all events in most of them, we were dealing to a large
extent with lines not seen in our laboratories when dealing
with terrestrial substances ; this work went on till ultimately,
thanks to the labours of Professor Young in America, we
had a considerable list of lines coming from known and un-
known substances which had been observed under these
conditions in solar disturbances, and Professor Young was
enabled to indicate the relative number of times these lines
were visible. For instance, the lines which are most
frequently seen under these conditions he tabulated as
represented by the number 100, and of course the line
which was least frequently seen would be represented by
1 ; and therefore from these so-called "frequencies" we
got a good idea of the number of times we might expect
to see any of these disturbance-lines when anything was
going on in the sun.

It was this kind of work which made Tennyson write
those very beautiful lines :

" Science reaches forth her arms
To feel from world to world ".1

1 And then he added :

" and charms
Her secret from the latest moon ".

I mention this because Tennyson, whose mind was saturated with
astronomy, had already grasped the fact that what had already been done
was a small matter compared with what the spectroscope could do ; and
now the prophecy is already fulfilled, for by means of the spectroscopic
examination of the light from the stars we can tell that some of them are
double stars, that is to say, in poetic language, stars with attendant moons.
Although we can thus charm the secret from each moon by means of the
spectroscope, to see the moon it would require (in the case of (3 Aurigse) a
telescope not eighty feet long, but with an object-glass eighty feet in dia-
meter, because the closer two stars are together the greater must be the
diameter of the object-glass, independently cf its focal-length and magnifying
power.

THE GROWTH OF OUR KNOWLEDGE OF HELIUM. 257

DR. HILLEBRAND'S RESEARCHES ON URANINITE, 1888.

In this year Dr. Hillebrand, one of the officials in the
Geological Department at Washington, was engaged upon
the chemical examination of specimens of the mineral
uraninite from various localities.

He dealt with crystals which he put in a vessel contain-
ing some sulphuric acid and water. He found that bubbles
of gas were produced out of the crystal by means of the
sulphuric acid. He collected this gas and came to the
conclusion that it was nitrogen.

This result was new. He thus wrote about it : —

"In consequence of a certain observation " [the one I
have just referred to] " and its results, an entirely new
direction was given to the work, and its scope wonderfully
broadened. This was the discovery of a hitherto un-
suspected element in uraninite, existing in a form of com-
bination not before observed in the mineral world."

It is not needful here to follow -Dr. Hillebrand through
all the painstaking and patient labour he cut out for him-
self to explain this anomalous behaviour. Needless to
say he did not omit to employ the spectroscope to test the
nature of the new gas.

His observations were thus described : — 1

"In a Geissler tube under a pressure of ten milli-
metres and less, the gas afforded the fluted spectrum of
pure nitrogen as brilliantly and as completely as was done
by a purchased nitrogen tube. In order that no possibility
of error might exist, the tube was then reopened and
repeatedly filled with hydrogen, and evacuated till only the
hydrogen lines were visible. When now filled with the
gas and again evacuated, the nitrogen spectrum appeared
as brilliantly as before, with the three bright hydrogen lines
added."

On this paragraph I may remark that it has long been
known that gases like nitrogen give us quite distinct spectra
at different temperatures — one fluted, another containing

1<(On the Occurrence of Nitrogen in Uraninite," Bulletin, No. 78,
U.S. Geol. Survey, 1889-90, p. 55.

258 SCIENCE PROGRESS.

lines. Which of these we shall see in a tube will depend
upon the pressure of the gas and the electric current used.
The fluted spectrum of nitrogen is very bright and full of
beautiful detail in the orange part of the spectrum ; the line
spectrum, on the other hand, is almost bare in that region.

It is important to note that it so happened 'that the pressure
and electric conditions employed by Dr. Hillebrand enabled
him generally to see the fluted spectrum. This however
was not always the case. In an interesting letter to Pro-
fessor Ramsay he writes (Proc. Roy. Soc, vol. lviii., p. 81): —

" Both Dr. Hallock and I observed numerous bright
lines on one or two occasions, some of which apparently
could be accounted for by known elements — as mercury, or
sulphur from sulphuric acid ; but there were others which I
could not identify with any mapped lines. The well-known
variability in the spectra of some substances under varying
conditions of current and degree of evacuation of the tube
led me to ascribe similar causes for these anomalous appear-
ances, and to reject the suggestion made by one of us in a
doubtfully serious spirit, that a new element might be in
question."

Dr. Hillebrand concludes his paper as follows : —

"The interest in the matter is not confined merely to a
solution of the composition of this one mineral ; it is broader
than that, and the question arises : May not nitrogen be a
constituent of other species in a form hitherto unsuspected
and unrecognisable by our ordinary chemical manipulations?
And, if so, other problems are suggested which it is not now
in order to discuss."

D3 AND OTHER UNKNOWN LINES IN NEBULA, 1890.

A negative of the nebula of Orion, taken at my observatory
at Westgate-on-Sea in 1890, contains fifty-six lines, and of
course by determining, as we have been able to do approxi-
mately, the wave-lengths — the positions of these lines in
the spectrum — we can determine the exact light notes
represented, and therefore the substances which produce
them. In this spectrum of the nebula of the Orion were

THE GROWTH OF OUR KNOWLEDGE OF HELIUM. 259

lines of unknown origin exactly coinciding with those un-
known lines which I have already referred to as having
been seen in the sun's atmosphere. Some of the un-
known lines in that atmosphere, those that we have not
been able to see in our laboratories, are identical in position
with some of the unknown lines in the nebula of Orion.

I may remark that as early as 1886 Dr. Copeland had
discovered D3 in the visible spectrum of the nebula, and
in a letter to him I had suggested that another line he had
recorded at 447 might be Lorenzoni's f\ this he thought
to be probable. The matter was set for ever at rest by
the photograph which established the presence of 4471 and
4026 as well, already noted as a solar line.

Professor Campbell, of the Lick Observatory, obtained
other photographs of the spectrum of the nebula some two
or three years after mine was taken. In the following list
of lines in my photograph an asterisk denotes that Campbell
gives a line nearly in the same position. He recorded
no line which did not appear on my photograph.

3896*
3888*
401 1
4026*
4121*

4143*

4168

4390*

4472*

4716*

4924

5875-8 = D3
THE SAME UNKNOWN LINES OCCUR IN THE STARS, 1892.

About the year 1890 I began the photography of stellar
spectra at Kensington, with special reference to their
classification on the basis of the chemical constituents
established by their spectra. By 1892 several important
results had been obtained, while the progress of this branch
of science lately has been so considerable that any state-
ment regarding the positions of lines, and therefore the

260 SCIENCE PROGRESS.

chemical origins of them, may be made with a considerable
amount of certainty as depending upon very accurate work.

The various classes in which the stars have been
classified by different observers according to their spectra
are discussed elsewhere, but some of the more salient differ-
ences must be pointed out here ; thus we have stars with
many lines in their spectra, others with comparatively few.
I will take the many-lined stars first.

The diagram (Fig. 8) represents the spectrum of
Arcturus, a star the spectrum of which closely resembles
that of the sun. In a Cygni we have another star with
many lines, but here we note, when we leave the hydrogen
on one side and deal with the other stronger lines, that
there is little relation between the solar spectrum and these
lines.

I next come to the stars with few lines : these are well
represented by many of the chief stars in the Constellation
of Orion. Bellatrix is given as an example (Fig. 9).

Then, I have next to say that in the photographs of the
spectra of many stars, chiefly of those more or less like
Bellatrix, we found the same lines which we have so far
classified as unknown for the reason that in our laboratories
we have not been able to get any lines which correspond
with them. I again mention D3, 4471 and 4026, previously
noted as appearing both in the chromosphere and in the
nebula of Orion.

But the thing is much more interesting even than this ;
not only these, but all the chief unknown lines appearing in
the nebula of Orion are also found in these stars. And this
is so absolutely true that there is no necessity to give a list
of the unknown lines seen in Bellatrix ; every one of them
given in the nebula has found its place, and (so far) practically
no others.

This of course marked a great development of the
inquiry, and makes the question of the unknown lines
more important than ever.

THE GROWTH OF OUR KNOWLEDGE OF HELIUM. 261

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262 SCIENCE PROGRESS.

PHOTOGRAPHIC RESULTS DURING A SOLAR ECLIPSE, 1893.

A method which was first employed by Respighi and
myself during the eclipse of 1871, was employed on a
large scale and with great effect during the eclipse of 1893.
The light proceeding from the luminous ring round the
dark moon was made to give us a series of rings, represent-
ing each bright line seen by the ordinary method on a
photographic plate. The observers this time were stationed
in West Africa and in Brazil. The African station was
up one of the rivers, not very far away from the town of
Bathurst. The Brazilian station was near Para Curu. The
same instrument which was previously referred to as used for
obtaining photographs of the stars was sent to the African
station in order that photographs of the eclipse of the sun
might be taken on exactly the same scale as the photo-
graphs of the stars had been, so that the stellar and solar
records in the photographs might be compared. The results
obtained by Messrs. Fowler and Shackleton, who were in
charge of the instruments at the two stations, will be gathered
from the accompanying diagrams, Figs. 10 and 11.

We get more or less complete rings when we are deal-
ing with an extended arc of the chromosphere, or lines of
dots when any small part of it is being subjected to a dis-
turbance which increases the temperature and, possibly,
the numbers of the different vapours present.

The efficiency of this method of work with the dis-
persion employed turns out to be simply marvellous, and in
securing such valuable and permanent records as these, we
have done very much better than if we had contented our-
selves with the style of observations that I have referred to
as having been made in 1871.

As was expected the comparison between solar and
stellar records thus rendered possible enabled a very great
advance to be made.

On examining these eclipse records, we find that we
have to do exactly with those unknown lines which had
already been photographed in the stars and in the nebulas.

As was to be expected we, of course, deal with the lines

THE GROWTH OF OUR KNOWLEDGE OF HELIUM. 263

264 SCIENCE PROGRESS.

recorded in the first observations of the solar disturbances,
and chronicled in that table of Professor Young's to which
I have already called attention ; but the important thing is
the marvellously close connection between eclipse- and star-
spectrum photographs so far as the "unknown lines" are
concerned.

Nearly all the lines given in the table on p. 259 as
visible in the Nebula of Orion and afterwards found in
Bellatrix, are also among the lines photographed during the
eclipse.

DISCOVERY OF A TERRESTRIAL SOURCE OF HELIUM, 1895.

The year 1894 was made memorable by the announce-
ment of the discovery by Lord Rayleigh and Professor
Ramsay of a new gas called argon, and you know that the
discovery was brought about chiefly in the first instance
by the very accurate observations of Lord Rayleigh, who
found that when he was determining the weight of air in
the globe of a certain capacity, the weight depended upon
the source from which he got the nitrogen.

From the nitrogen from atmospheric air he obtained one
weight, and from that obtained by certain chemical pro-
cesses he obtained another, and ultimately it was found that
there was an unknown element which produced these results,
these various changes in the weight, and as a consequence
we had the 1895 discovery of argon.

Early in 1895 it struck Mr. Miers, of the British
Museum, that it might be desirable to draw attention to
the nitrogen which we have seen Dr. Hillebrand in 1888
obtaining from his crystal of uraninite ; his observations, of
course, were more in the mind of Mr. Miers than in the
minds of the pure chemists. He therefore communicated
with Professor Ramsay, who lost no time, because it was
very interesting to study every possible source of nitrogen
and see what its behaviour was in regard to the quantity
of argon that it produced, and in the relation generally of the
gas to the argon which was produced from it.

Professor Ramsay treated uraninite in exactly the same

THE GROWTH OF OUR KNOWLEDGE OF HELIUM. 265

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266 SCIENCE PROGRESS.

way that Dr. Hillebrand had done in 1888. The gas
obtained as Dr. Hillebrand had obtained it was eventually-
submitted to a spectroscopic test, following Dr. Hillebrand's
example. But here a noteworthy thing comes in.

It so happened that the pressure and electrical conditions
employed by Professor Ramsay were so different from those
used by Dr. Hillebrand that, although nitrogen was un-
doubtedly present, the fluted spectrum which, as I have
previously stated, floods the orange part of the spectrum
with luminous details, was absent. But still there was
something there.

Judge of Professor Ramsay's surprise when he found
that he got a bright orange line ; that was the chief thing,
and not the strong suggestion of the spectrum of nitrogen.
Careful measurements indicated that the twenty-six-year-
old helium had at last been run to earth, D3 was at last
visible in a laboratory. Professor Ramsay was good enough
to send specimens of the tubes containing this gas round
to other people, and he sent one of them to me.

I received Professor Ramsay's tube on 28th March, but
it was not suitable for the experiments I wished to make.

On 29th March, therefore, as Professor Ramsay was
absent from England, in order not to lose time I determined
to see whether the gas which had been obtained by chemical
processes would not come over by heating in vacuo, after the
manner described by me to the Royal Society in 1879/and Mr.
L. Fletcher was kind enough to give me some particles of
uraninite (broggerite) to enable me to make the experiment.

This I did on 30th March, and it succeeded ; the gas
giving the yellow line came over, associated with hydrogen,
in good quantity.

From 30th March onwards my assistants and myself
had a very exciting time. One by one the unknown lines
I had observed in the sun in 1868 were found to belong to
the gas I was distilling from broggerite ; not only D3 but
4923, 5017, 4471 (Lorenzoni's/), 6677 (the B C of Fig. 7),
referred to previously, and many other solar lines, were all
caught in a few weeks.

1 Roy. Soc. Proc, vol. xxix., p. 266.

THE GROWTH OF OUR KNOWLEDGE OF HELIUM. 267

But this was by no means all. The solar observations
had been made by eye, and referred therefore to the less
refrangible part of the spectrum, but I had obtained and
studied hundreds of stellar photographs, so I at once pro-
ceeded to photograph the gas and compare its more re-
frangible lines with stellar lines.

Here, if possible, the result was still more marvellous.
In the few-lined stars by 6th May I had caught nearly all
the most important lines at the first casts of the spectroscopic
net. Fig. 1 5, which includes some later results, will give an
idea of the tremendous revelation which had been made as
to the chemistry of some of the stages of star-life. I
pointed out on 8th May that we had already "run home "
the most important lines in the spectra of Group III. in
which stars alone we find D3 reversed.

These results enabled us at once to understand how it
was that the "unknown lines" had been seen both in the
sun's chromosphere and some nebulae and stars. The gas
obtained from the minerals made its appearance in the
various heavenly bodies in which the conditions of the
highest temperatures were present ; and the more the work
goes on, we find that this gas is really the origin of most,
but certainly not of all, of the unknown lines which have
been teasing astronomical workers for the last quarter of a
century.

THE FIRST INVESTIGATIONS OF THE SPECTRUM OF THE

GAS FROM CLEVEITE.

The dates of the papers communicated to the Royal
Society recording the observations of the lines in the gas
obtained from minerals which had been previously recorded
are as follows : —

4026

4922

The lines at 667 and 5016 had been previously seen
by Thalen (Comptes Rendus, 16th April, 1895).

25 th April, -

- 447i

4144

8th May,

- 667

4388

9th May,

- 3889

28th May, -

- 7065

29th May, -

- 5048

5016

268 SCIENCE PROGRESS.

Although the general distribution and intensities of the
lines in the gases from broggerite and cleveite sufficiently
corresponded with some of the chief " unknown lines " in
the solar chromosphere and some of the stars to render
identity probable, it was necessary to see how far the con-
clusion was sustained by detailed investigations of the
wave-lengths of the various lines.

EMPLOYMENT OF HIGH DISPERSION.

This was practically a separate branch of the work, as
the observations had to be made in the observatory. Next
I give here the observations relating- to D3, 4471.

The Orange Line, A 5875*9. — Immediately on receiving
from Professor Ramsay, on 28th March, a small bulb of the
gas obtained from cleveite, a provisional determination of
wave-length was made by Mr. Fowler and myself, in the
absence of the sun, by micrometric comparisons with the D
lines of sodium, the resulting wave-length being 5876*07
on Rowland's scale. It was at once apparent, therefore,
that the gas line was not far removed from the chromo-
spheric D3, the wave-length of which is given by Rowland

as 5875'98.

The bulb being too much blackened by sparking to give
sufficient luminosity for further measurements, I set about
preparing some of the gas for myself by heating broggerite
in vacuo, in the manner I have already described. A new
measurement was thus secured on 30th March, with a
spectroscope having a dense Jena glass prism of 6o° ; this
gave the wave-length 5876*0.

On 5th April, I attempted to make a direct comparison
with the chromospheric line, but though the lines were
shown to be excessively near to each other, the observa-
tions were not regarded as final.

Professor Ramsay having been kind enough to furnish
me, on 1st May, with a vacuum tube which showed the
orange line very brilliantly, a further comparison with the
chromosphere was made on 4th May. The observations
were made by Mr. Fowler, in the third order spectrum of
a grating having 14,438 lines to the inch, and the observing

THE GROWTH OF OUR KNOWLEDGE OF HELIUM. 269

telescope was fitted with a high power micrometer eye-
piece ; the dispersion was sufficient to easily show the
difference of position of the D3 line on the east and west
limbs, due to the sun's rotation. Observations of the
chromosphere were therefore confined to the poles.

During the short time that the tube retained its great
brilliancy, a faint line, a little less refrangible than the
bright orange one, and making a close double with it, was
readily seen ; but afterwards a sudden change took place,
and the lines almost faded away. While the gas line was
brilliant, it was found to be " the least trace more refrangible
than D3, about the thickness of the line itself, which was
but narrow" ("Observatory Note Book"). The sudden
diminution in the brightness of the lines made subsequent
observations less certain, but the instrumental conditions
being slightly varied, it was thought that the gas line was
probably less refrangible than the D3 line by about the
same amount that the first observation showed it to be
more refrangible. Giving the observations equal weight,
the gas line would thus appear to be probably coincident
with the middle of the chromospheric line, but if extra
weight be given to the first observation, made under much
more favourable conditions, the gas line would be slightly
more refrangible than the middle of the chromosphere line.

Pressure of other work did not permit the continuation
of the comparisons. In the meantime, Runge and Paschen
announced (Nature, vol. Hi., p. 128) that they also had seen
the orange line of the cleveite gas to be a close double,
neither component having exactly the same wave-length as
D3, according to Rowland.

They give the wave-length of the brightest component as
5878*883, and the distance apart of the lines as 0*323.

This independent confirmation of the duplicity of the
gas line led me to carefully re-observe the D3 line in the
chromosphere for evidences of doubling. On 14th June
observations were made by Mr. Shackleton and myself of
the D3 line in the third and fourth order spectra under
favourable conditions ; " the line was seen best in the fourth
order, on an extension of the chromosphere or prominence

270 SCIENCE PROGRESS.

on the north-east limb of the sun. The D3 line was seen
very well, having every appearance of being double, with a
faint component on the red side, dimming away gradually ;
the line of demarcation between the components was not
well marked, but it was seen better in the prominence than
anywhere else on the limb " (" Observatory Note Book ").

It became clear, then, that the middle of the chromo-
sphere line, as ordinarily seen, and as taken in the
comparison of 4th May, does not represent the place of
the brightest component of the double line, so that exact
coincidence was not to be expected.

The circumstance that the line is double in both gas
and chromosphere spectrum, in each the less refrangible
component being the fainter, taken in conjunction with the
direct comparisons which have been made, rendered it
highly probable that one of the gases obtained from cleveite
is identical with that which produces the D3 line in the
spectrum of the chromosphere.

Other observers have since succeeded in resolving the
chromospheric line. On 20th June, Professor Hale found
the line to be clearly double in the spectrum of a promin-
ence, the less refrangible component being the fainter, and
the distance apart of the lines being measured as 0*357
tenth -metres (Ast. JVac/i., 3302).

The doubling was noted with much less distinctness in
the spectrum of the chromosphere itself on 24th June.
Professor Hale points out that Rowland's value of the wave-
length (as well as that of 5875*924, determined by himself
on 19th and 20th June) does not take account of the fact
that the line is a close double.

Dr. Huggins, after some failures, observed the D3 line
to be double on 10th July [Ast. Nack., 3302); he also
notes that the less refrangible component was the fainter,
and that the distance apart of the lines was about the same
as that of the lines in the gas from cleveite, according to
Runge and Paschen.

It may be added, that in addition to appearing in the
chromosphere, the D3 line has been observed as a bright
line in nebulae by Dr. Copeland, Professor Keeler and

THE GROWTH OF OUR KNOWLEDGE OF HELIUM. 271

others ; in /3 Lyrae and other bright line stars ; and as a
dark line in such stars as Bellatrix, by Mr. Fowler, Pro-
fessor Campbell and Professor Keeler. In all these cases
it is associated with other lines, which, as I shall show pre-
sently, are associated with it in the spectra of the new gases.

The Blue Line, A 4471*8. — A provisional determination
on 2nd April of the wave-length of a bright blue line, seen
in the spectrum of the gases obtained from a specimen of
cleveite, showed that it approximated very closely to a
chromospheric line, the frequency of which is stated as 100
by Young.

This line was also seen very brilliantly in the tube
supplied to me by Professor Ramsay on 1st May, and on
6th May it was compared directly with the chromosphere
line by Mr. Fowler. The second order grating spectrum
was employed. The observations in this region were not
so easy as in the case of D3, but with the dispersion em-
ployed, the gas line was found to be coincident with the
chromospheric one. In this case also, the chromosphere
was observed at the sun's poles, in order to eliminate the
effects due to the sun's rotation.

Besides appearing in the spectrum of the chromosphere,
the line in question is one of the first importance in the
spectra of nebulae, bright line stars, and of the white stars
such as Bellatrix and Rigel.

The Infra-red Line, \ 7065*5. — In addition to D3 and
the line at 447 1 '8, there is a chromospheric line in the infra-
red which also has a frequency of 100, according to Young.
On 28th May I communicated a note to the Royal Society
stating that this line had been observed in the spectrum of
the gases obtained from broggerite and euxenite {Roy. Soc.
Proc, vol. lviii., p. 192), solar comparisons having con-
vinced me that the wave-length of the gas line corresponded
with that given by Young ; and I added : " It follows, there-
fore, that besides the hydrogen lines all three chromospheric
lines in Young's list which have a frequency of 100 have
now been recorded in the spectra of the new gas or gases
obtained from minerals by the distillation method ".

M. Deslandres, of the Paris Observatory, has also

272 SCIENCE PROGRESS.

observed the line at 7065 in the gas obtained from the
cleveite (Comptes Rendus, 17th June, 1895, p. 1 331).

A great deal of work has been done upon these gases
from other points of view than those which affect their
cosmical relations, and perhaps I may be allowed next to
refer to some of the results which have been obtained by
myself.

HELIUM NOT CONNECTED WITH ARGON.

The first point is that the gas from the minerals contains
no argon. Dr. Ramsay in his first experiments came to the
conclusion that the spectra of argon and helium contained
many common lines ; indeed at first the observed coin-
cidences were so remarkable that he came to the conclusion
that the connection was so close that atmospheric argon con-
tained a gas absent from the argon seen in his helium tube.

This statement was subsequently withdrawn, but the
compound nature both of argon and helium was suggested
by the fact that there were lines common to the two gases.
These lines were in the red ; one coincidence I found broke
down with moderate dispersion, the other yielded subse-
quently to the still greater dispersion employed by Drs.
Runge and Paschen. It may be also stated here that I have
not found a single coincidence between argon and any line
in the spectrum of any celestial body whatever. This
happens, as everybody knows, also in the case of oxygen,
nitrogen, chlorine, and the like.

THE CLEVEITE GAS A COMPOUND.

The first spectroscopic observations made it perfectly
obvious that the gas as obtained from uraninite is a mixture
of gases, that the gas which gives the yellow line is not an
isolated one, but is mixed up with other gases which give
other lines.

In May I wrote as follows : — 1

" The preliminary reconnaissance suggests that the gas
obtained from broggerite by my method is one of complex
origin.

1 Proc. R. S., Iviii., p. 114.

THE GROWTH OF OUR KNOWLEDGE OF HELIUM. 273

" I now proceed to show that the same conclusion holds
good for the gases obtained by Professors Ramsay and
Cleve from cleveite.

" For this purpose, as the final measures of the lines of
the gas as obtained from cleveite by Professors Ramsay and
Cleve have not yet been published, I take those given by
Crookes and Cleve, as observed by Thalen.

" The most definite and striking result so far obtained is
that in the spectra of the minerals giving the yellow line
I have so far examined, I have never once seen the lines
recorded by Crookes and Thalen in the blue. This demon-
strates that the gas obtained from certain specimens of
cleveite by chemical methods is vastly different from that
obtained by my method from certain specimens of brog-
gerite, and since, from the point of view of the blue lines,
the spectrum of the gas obtained from cleveite is more
complex than that of broggerite, the gas itself cannot be
more simple.

" Even the blue lines themselves, instead of appearing
en bloc, vary enormously in the sun, the appearances being

4922 (4921-3) = thirty times
4713 (47 1 2-5) = twice.

" These are not the only facts which can be adduced to
suggest that the gas from cleveite is as complex as that
from broggerite."

It is seen that quite early in the inquiry we had not only
spectroscopic evidence in the laboratory which was com-
plete in itself, but that the case was greatly strengthened
when the behaviour of the various lines in the sun and stars
was also brought into evidence.

In the first case we had the laboratory separation of D,
from the lines 5048, 5016, and 4922.

Later on in the same month I showed that the lines at
D3 and 447 behaved in one way, and that at 667 behaved
in another.

In order to test this view I made some observations
based on the following considerations : —

(1) In a simple gas like hydrogen, when the tension of
the electric current given by an induction coil is increased

274 SCIENCE PROGRESS.

by inserting first a jar and then an air-break into the circuit,
the effect is to increase the brilliancy and the breadth of all
the lines, the brilliancy and breadth being greatest when the
longest air-break is used.

(2) Contrariwise, when we are dealing with a known
compound gas ; at the lowest tension we may get the
complete spectrum of the compound without any trace of
its constituents, and we may then, by increasing the tension,
gradually bring in the lines of the constituents, until, when
complete dissociation is finally reached, the spectrum of the
compound itself disappears.

Working on these lines the spectrum of the spark at
atmospheric pressure passing through the gas or gases,
distilled from broggerite, has been studied with reference
to the special lines C (hydrogen), D3, 667, and 447.

The first result is that all the lines do not vary equally
as they should do if we were dealing with a simple gas.

The second result is that at the lowest tension 667 is
relatively more brilliant than the other lines ; on increasing
the tension C and D3 considerably increase their brilliancy,
667 relatively and absolutely becoming more feeble, while
447, seen easily as a narrow line at low tension, is almost
broadened out into invisibility as the tension is increased
in some of the tubes, or is greatly brightened as well as
broadened in others (Fig. 12).

4471

D3

5875.

c

6563 667.

1.

Mi

Fig. 12. — Diagram showing changes in intensities of lines brought about by varying the
tension of the spark, i. Without air-break. 2. With air-break.

The above observations were made with a battery of
five Grove cells ; the reduction of cells from 5 to 2 made
no difference in the phenomena except in reducing their
brilliancy.

Reasoning from the above observations it seems evident
that the effect of the higher tension is to break up a com-
pound or compounds, of which C, D3, and 447 represent
constituent elements ; while, at the same time, it would

THE GROWTH OF OUR KNOWLEDGE OF HELIUM. 275

appear that 667 represents a line of some compound which
is simultaneously dissociated.

The unequal behaviour of the lines has been further
noted in another experiment, in which the products of
distillation of broggerite were observed in a vacuum tube
and photographed at various stages. After the first heating
D3 and 447 1 were seen bright, before any lines other than
those of carbon and hydrogen made their appearance.
With continued heating 667, 5016, and 492 also appeared,
although there was no notable increase of brightness in the
yellow line ; still further heating introduced additional lines,
5048 and 6347.

These changes are represented graphically in the fol-
lowing diagram (Fig. 13).

D3

447. 492.501. 5876. 634 667.

504
Fig. 13. — Diagram showing order in which lines appear in spectrum of vacuum tube

when broggerite is heated.

It was recorded further that the yellow line was at times
dimmed, while the other lines were brightened.

In my second note, communicated to the Royal Society
on the 8th May, I stated that I had never once seen the
lines recorded by Thalen in the blue, at A 4922 and 4715.

It now seems possible that their absence from my
previous tubes was due to the fact that the heating of the
minerals was not sufficiently prolonged to bring out the
gases producing these lines.

It is perhaps to the similar high complexity of the gas
obtained from cleveite that the curious behaviour of a tube
which Professor Ramsay was so good as to send me, must
be ascribed. When I received it from him the glorious
yellow effulgence of the capillary while the current was
passing was a sight to see. But after this had gone on
for some time, while the coincidence of the yellow line with
D3 of the chromosphere was being inquired into, the lumi-
nosity of the tube was considerably reduced, and the colours

276 SCIENCE PROGRESS.

in the capillary and near the poles were changed. From
the capillary there was but a feeble glimmer, not of an
orange tint, while the orange tint was now observed near
the poles, the poles themselves being obscured by a coating
on the glass of brilliant metallic lustre.

After attempting in vain for some time to determine the
cause of the inversion of D3 and 447 in various photographs
I had obtained of the spectra of the products of distillation
of many minerals, it struck me that these results might be
associated with the phenomena exhibited by the tube, and
that one explanation would be rendered more probable if it
could be shown that the change in the illumination of the tube
was due to the formation of platinum compounds, platinum
poles being used. On 2 1st May I accordingly passed the cur-
rent and heated one of the poles, rapidly changing its direction
to assure the action of the negative pole, when the capillary
shortly gave a very strong spectrum of hydrogen, both lines
and structure. A gentle heat was continued for some time,
and apparently the pressure in the tube varied very con-
siderably, for as it cooled the hydrogen disappeared and the
D3 line shone out wTith its pristine brilliancy. The experi-
ment was repeated on 24th May, and similar phenomena
were observed.

Some little time after1 Professors Runge and Paschen,
from an entirely different standpoint, arrived at exactly the
same conclusion.

The employment of exposures extending over seven
hours has given a considerable extension in the number of
lines, and the bolometer has been called in to investigate
lines in the infra-red ; better still, they have employed well-
practised hands in searching for series of lines. Operating
by chemical means upon a crystal of cleveite free from any
other mineral, they have obtained a product so pure that
from these series there are no outstanding lines. Very
great weight, therefore, must be attached to their conclusions.

As a result of their investigations Drs. Runge and
Paschen stated that the gas given off even by a pure crystal

1 Nature, 26th September, 1895.

THE GROWTH OF OUR KNOWLEDGE OF HELIUM. 277

of cleveite is not simple. In their view the mixture consists
of two constituents.

This conclusion was arrived at from the following con-
siderations. " The wave-lengths A of the lines belonging to
the same series are always approximately connected by a
formula somewhat similar to Balmer's —

i/X = A - B/;//2 - C/m\

A determines the end of the series towards which the lines
approach for high values of m, but does not influence the
difference of wave-numbers of any two lines. B has nearly
the same value for all the series observed, and C may be
said to determine the spread of the series, corresponding
intervals between the wave-numbers being larger for larger
values of C. As B is approximately known two wave-
lengths of a series suffice to determine the constants A and
C, and thus to calculate approximately the wave-lengths of
the other lines. It was by this means that we succeeded in
disentangling the spectrum of the gas in cleveite, and
showing" its regularity.

"In the spectrum of many elements two series have been
observed for which A has the same value, so that they both
approach to the same limit. In all these cases the series
for which C has the smaller value, that is to say, which has
the smaller spread, is the stronger of the two. In the
spectrum of the gas in cleveite we have two instances of
the same occurrence. One of the two pairs of series, the
one to which the strong yellow double line belongs, consists
throughout of double lines whose wave-numbers seem to have
the same difference, while the lines of the other pair of series
appear to be all single. Lithium is an instance of a pair of
series of single lines approaching to the same limit. But
there are also many instances of two series of double lines
of equal difference of wave-numbers ending at the same
place as sodium, potassium, aluminium, etc. There are also
cases where the members of each series consist of triplets of
the same difference of wave-numbers, as in the spectrum of
magnesium, calcium, strontium, zinc, cadmium, mercury.
But there is no instance of an element whose spectrum
contains two pairs of series ending at the same place. This

278 SCIENCE PROGRESS.

suggested to us the idea that the two pairs of series belonged
to different elements. One of the two pairs being by far
the stronger, we assume that the stronger one of the two
remaining series belongs to the same element as the stronger
pair. We thus get two spectra consisting of three series
each, two series ending at the same place, and the third
leaping over the first two in large bounds and ending in the
more refrangible part of the spectrum. This third series we
suppose to be analogous to the so-called principal series in
the spectra of the alkalis, which show the same features.
It is not impossible, one may even say not unlikely, that
there are principal series in the spectra of the other elements.
But so far they have not been shown to exist.

" Each of our two spectra now shows a close analogy to
the spectra of the alkalis.

"We therefore believe the gas in cleveite to consist of
two, and not more than two, constituents."

To the one containing the line D3, which I discovered
in 1868, the name helium remains ; the other for the present
we may call " gas X V

The chief lines of these two constituents are as follows,
according to Runge and Paschen, the wave-lengths being
abridged to five figures.

i

Hi I ol

I II] L

8
If '

i !

~'^r

r 5

1L

Li

,r in.

1

j A

• .1

'

ttSTtTUCHY ■ CAS

1

j

i

\
1
J _

i
i

!

i

j

i

'-'

j

"** '

i

Fig. 14. — Runge and Paschen's results suggesting that cleveite gives off
two gases, each with three series of lines.

1 In the many comparisons I had to make, I soon found the incon-
venience of not having a name for the gas which gave 667, 501 and other
lines. When, therefore, Professors Runge and Paschen, who had endorsed

THE GROWTH OF OUR KNOWLEDGE OF HELIUM. 279

HELIUM.

1st Subordinate

2nd Subordinate

Principal Series.

Series.

Series.

2663-3

3456-9?

3481-6

2677-2

3461-4?

3490-8

2696-2

3466-0

3502-5

2723-3

347I-9

35I7-5

2763-9

3479'1

3537-0

2829-2

3487-9

3563-I

2945-2

3498-8

3733'0

3187-8

35I2'6

3867-6

3888-8

353o-6

4121-0

3554-6

4713-3

3587-4

7065-5

3634-4

3705-1

3819-8

4026-3

4471-6

5875-8

GAS X.

1st Subordinate

1
and Subordinate

Principal Series.

Series.

Series.

3176-6

3756-2

3770-7

3196-8

3768-9

3787-6

3211-6

3785-o

3838-2

323I*3

3805-9

3878-3

3258-3

3833-7

3936-0

3296-9

3872-0

4024-1

3354-7

3926-7

4169-1

3447-7

4009-4

44377

3613-8

4143-9

5047-8

3964-9

4388-1

7281-8

5oi5-7

4922*1
6678-4

my results, and had extended them, called upon me, I thought it right to
suggest to them that, sinking the priority of my own results, we should all
three combine in suggesting a name. Professor Runge (under date 20th
October) wrote me : " The inference that there are two gases is a spectro-
scopical one, being based on the investigation of the ' series '. Now, though
we think this basis quite sound, we must own that the conclusion rests on
induction. . . . For this reason we do not want to give a name to ' gas
X '." I have so far suggested no name, though Orionium and Asterium
have been in my mind.

280

SCIENCE PROGRESS.

More recently Professor Ramsay has abandoned his
view of the simple nature of the cleveite gas, and states
that from his experiments "there appears ground for the
supposition that helium is a mixture ".1

THE EXISTENCE OF THE NEW GASES IN CELESTIAL BODIES.

And now comes the great revelation, and it is this.
The majority of the lines classed as unknown in the spectra
of the Orion nebula, stars of Group III. and the sun are
really due to the cleveite gases.

The following table sets this result out. It will be seen
that of seventeen unknown lines, twelve have been run to
earth.

COMPARISON OF UNKNOWN {PREVIOUS TO HE. AND X)
LINES IN ORION NEBULA AND BELLA TRIX.

Orion Nebula.

Bellatrix and
Eclipse, 1893.

Origin.

Campbell.

Lockyer.

3869

*3869 (7)

t3867-5

(Falls

He.

3889

3888 (7)

3888onHe.)

He.

—

4°i 1 (3)

4009 (8;

X

4026

4026 (5)

4026 (10)

He.

—

4042 (1)

4041 (3)

Still Unknown

4067

4068 (3)

4°7° (3)

Still Unknown

4121

4121 (1)

4121-3(7)

He.

4H3

4143 (T)

4144 (8)

X

—

4168 (1)

4169 (5)

X

4265

4270 (3)

4268 (7)

Still Unknown

4389

439° (3)

4389 (8)

X

4472

4472 (7)

4472 (10)

He.

—

454° (3)

454i (1)

Still Unknown

—

4628 (3)

4630 (3)

Still Unknown

4714

47i6 (3)

47i5 (5)

He.

■ —

*4924 (5)

f4922-i (8)

X

5874

5875-8

5875-8

D3 He.

* Between these AA there are forty-two lines in the Orion photograph of which six are
known other than He. and X.

t Between these AA there are forty-five lines in the Bellatrix photograph of which
five are known other than He. and X.

The following tables give the complete list of lines
and the celestial body in which they have been traced.

1 Nature, vol. liii., p. 598.

THE GROWTH OF OUR KNOWLEDGE OF HELIUM. 281

In the tables, under "sun," C, followed by a number,
indicates the frequency as given by Young ; E indicates the
lines photographed during the eclipse of 1893. Under
"star or nebula" the references are to the tables given in
my memoir on the nebula of Orion {Phil. Trans., vol.
clxxxvi., 1895, P- 86 et seq. N = Nebula of Orion).

HELIUM.

I 1220.

Sun.

Star or Nebula.

3889

C E

N. III. y

3188

2945

2829

2764

'*

2723

2696

2677

5876

C 100 E

4472

C 100 E

4026

C 25 E

3820

E

a Cygni

3705^

3634

3537

3555

35I3

3499

>*

3488

3479

3472

3466

346iy

7066

C 100

47i3

C 2 E

4121

E

N. a Cygni

3868

?

3777

E

Bellatrix

3652

3599

3567

3537

35i7

'*

35°3

349i

3482,

* Means that these lines are out of the range of my observations.

20

282

SCIENCE PROGRESS.

GASX.

Sun.

Star or Nebula.

5016

C 30 E

3965

?

III. y

36M>

E

3448

3355

3297

.*

3258

3231

32i3J

6678

C 25

4922

C 30 E

4388

E

N. III. y

4144

E

III. y

4009

III. y

3927

Bellatrix

3872

Bellatrix

3833

E

Hid byH. line

3806

Bellatrix

3785*

7282

5048

C 2

4438

Bellatrix

4169

Bellatrix

4024

?

N. III. y

3936

Hid in K.

3878

C E

a Cygni

3838

C E

a Cygni

3803"-

* Means that these lines are out of the range of my observations.

The annexed reproduction of a photograph of Bellatrix
will show how striking has been the result of the discovery
so far as stellar spectra are concerned.

Hydrogen, helium and gas X are thus proved to be
those elements which are, we may say, completely repre-
sented in the hottest stars and in the hottest part of the
sun that we can get at. Here then, in 1895, we have
abundant confirmation of the views I put forward in
1868 as to the close connection between helium and
hydrogen.

THE GROWTH OF OUR KNOWLEDGE OF HELIUM. 283

EFFECTS OF DIFFUSION.

A diffusion experiment described in their paper enabled
Messrs. Runge and Paschen to go a stage farther, and to

x

a

31

0

■

M

(

Ln

J

3889

"|

H

3*

- -!: "

3926

W

*"0

rt
0

.

3964

rf

c

; ... _

t

3968

3
0

•;'■•■" HhSFv

i-h

«

4009

rt

;>

"rr

4026

p"

r*

K

-1

.• • ^S^f&v^i

rfi

\

3*

O

4101
4121

<

5'

era

1.

4143

cr 3*

...

4169

r* rt

p ,_.

S'5'

D- tzi

^KHvH

3>o

1 ■

-

- iy: '-y;~; y'y-^.

3^

3 g-

1

; .,.''■

5'°

*

SL 3

,

4340

Cfl ^

" 3

el-

-

4388

'.

''■"•■

s'

0

,- ■

*

;■

4437

C/3

rt

k

3

> z*

-v

• -

— U. ■ -

447 2

3*

n'

I •

s*

.

3*

p

<

re

'". -!

r:^,#*i^f':-'i

cr

n>

'*.

rt

<

3

*

t-t

M

P

O

rt

» - ! •'.

47*3

p.

rf

0

•

'

r+

%

W38&f&'

3"

£$£a, •' "-

rt

OQ

4860

P

W

rt

C/3

<-$ w w TJ

announce that of their two constituents the gas-giving D3
was the heavier one. They also add :—

" From the fact that the second set of series is on the

284 SCIENCE PROGRESS.

whole situated more to the refrangible part of the spectrum,
one may, independently of the diffusion experiment, con-
clude that the element corresponding to the second set is the
heavier of the two ".

As they themselves pointed out, however, the result was
not final, because the pressures were not the same. I have
recently made some experiments in which the pressures
remain the same.

An U tube was taken, and at the bend was fixed a
plaster of Paris plug about 1*5 cm. thick; in one of the
limbs two platinum wires were inserted. The plug was
saturated with hydrogen to free it from air ; the tube was
then plunged into a mercury trough, and fixed upright with
the limbs full of mercury. Into the leg (A) with the plati-
num wires a small quantity of hydrogen was passed, and as
soon after as possible another small quantity of a mixture
of helium and hydrogen from samarskite was put up the
other limb (B) of the U tube.

Immediately after the helium was passed into the limb
(B) spectroscopic observations were made of the gas in the
limb (A) ; D3 was already visible, and there was no trace of
50157. This result seems to clearly indicate that if a true
diffusion of one constituent takes place, the component which
gives D3 is lighter than the one which gives the lines at
wave-length 50157.

Although this result is opposed to the statement made
by Runge and Paschen, it is entirely in harmony with the
solar and stellar results.

In support of this I may instance that of the cleveite
lines associated with hydrogen in the chromosphere and the
stars of Group III. y ; those allied to D3 are much stronger
than those belonging to the series of which 50157 forms
part.

MINERALS EXAMINED.

So far I have worked upon some seventy minerals, and
I have found the orange line in sixteen.

The following are the minerals, etc., which have been

THE GROWTH OF OUR KNOWLEDGE OF HELIUM. 285

investigated ; those which give the D. line beino- marked
with an asterisk : —

*.Eschynite.

Almandine.

Anglesite.

Anhydrite.

Augite.

Barytes.
*Broggerite.

Bronzite.

Calco-uranite.

Cassiterite.

Celestine.

Chalk.

Charnockite.

Chromite.
*Cleveite.

Columbke.

Crocidolite.

Cupro-uranite.
*Eliasite.

Enstatite.
*Euxenite.
*Fergusonite.

Franklinite.

Gadolinite.

Gahnite.

Geikielite.

Gneiss.

Granite.

Graphite.
*Gummite.

Haematite.
*Hielmite.

Hornblende.

Hypersthene.

Ilmenite.

Iridosmine.
Kielhanite.

Kyanite.

Ludvvigite.

Magnesium.

Magnetite.

Manganese Nodule.

Minium.
*Monazite.

Obsidian.

Olivine.

Olivine-Enstatite.
*Orangeite.

Orthite.

Pitchblende.

Plumbic Ochre.
*Polycrase.
*Pyrochlore.

Quartz.

Red Clay.

Rhodonite.
*Samarskite.

Schurlomite.

Sphene.

Staurolite.

Thorite.
*Thoro-gummite.
*Uraninite.

Uranocircite.

Uranophase.

Wulfenite.

Wolfram.

Xenotine.
*Yttro-Gummite.

J. Norman Lockyer.

INSULAR FLORAS.

PART VI. (a).

IN the preceding articles I have briefly reviewed the
literature relating to Insular Floras which has appeared
during the last decade, and I have extracted therefrom the
principal or most interesting facts, which I have given with
some comments of my own. That I have been able to do
this with some profit is largely due to the advantages I have
enjoyed through the kindness of the Director of the Royal
Gardens, Kew. Since the publication in 1885 of my first
essay on this subject, in the Botany of the Voyage of H. M.S.
" Challenger" all or nearly all collections of insular plants
received at Kew have passed through my hands for determina-
tion and reporting on ; and I have also been favoured with
many notes and criticisms by travellers and other persons
interested in plant distribution. I propose therefore to
enter into a short recapitulation and discussion of the main
facts thus accumulated ; but before doing- so I will refer to
some more or less important contributions to the subject
that have come to light during the progress of the present
series of articles.1

It will be convenient to take the islands in the same
geographical order previously followed (1), beginning with
Polynesia.

There are some interesting recent contributions to the
flora of Polynesia, taking the designation in its widest
sense ; but no one has yet attempted to bring together what is
known, or ascertainable from materials preserved in herbaria,
of the vegetation of the numerous small coral islands and
groups of islands, more or less recently annexed by, or taken
under the protection of, Great Britain. This the writer is
engaged upon, and some particulars thus acquired may be

1 A review of the additional literature having extended beyond what
was expected, the discussion referred to will form the subject of a conclud-
ing article.

INSULAR FLORAS. 287

utilised here in dealing with the literature of the subject.
Some years ago Mr. J. T. Arundel delivered a lecture at
San Francisco, before the Geographical Society of the
Pacific, on the Phcenix Group and other islands of the
Pacific, and he has since published it (2) with additional
notes. Mr. Arundel writes from actual experience, having
visited a large number of the most remote islets of the
Pacific and collected samples of their scanty floras, which
were determined for him at Kew, where the specimens are
preserved. Unfortunately several of the names of the
plants in his list have undergone such a transformation as
to be almost unrecognisable.

Besides the Phcenix Group, which was under his personal
control, Mr. Arundel visited such out-of-the-way islands as
Starbuck, Caroline (not the Caroline Group), Fanning,
Maiden, Palmerston and Ducie. Mr. Arundel describes
Starbuck and Caroline Islands as examples of two kinds of
very small islands common in the Pacific, though not con-
fined to it. The former represents those consisting of an
unbroken mass which is treeless, and indeed almost devoid
of vegetation ; and the latter is a typical coral atoll, con-
sisting of a ring of islets encircling a central lagoon, and
supporting a relatively luxuriant vegetation. Starbuck is
very scantily furnished with vegetation, only about half a
dozen species being represented. The principal plants are
Lepidium piscidium and Sida fallax ; both of wide range
in Polynesia. Caroline Island claims a little more atten-
tion, because its history, position, conformation, meteorology,
botany and zoology have been very fully worked out and
illustrated. In 1883 this island was selected by the Ameri-
cans, by the British, and by the French as the most suitable
spot for observing the total eclipse of the sun. The Ameri-
can party was relatively numerous, and they drew up a
somewhat elaborate report (3), illustrated chiefly by prints
from photographs taken by the two gentlemen constituting
the English party. These illustrations give an excellent
idea of the form and vegetation of an atoll, including a
bird's eye view, which enables us, better than any description
could, to realise its smallness and isolation. Caroline Island

288 SCIENCE PROGRESS.

is situated in almost exactly 150° W. longitude and io° S.
latitude, and is distant, according to Mr. Arundel, about
400 miles from Tahiti, the nearest island of considerable
size — say a third larger than the Isle of Wight ; and 420
from Starbuck. Although in most parts well clothed with
vegetation, this vegetation consists of very few, perhaps
not more than twenty, species of vascular plants. Several
others now exist, either as the remains of cultivation or
accidental introduction ; and the abundance of the cocoanut
palm is due to planting, which has now been in operation
for some years. Whether the cocoanut existed in the
island on the first advent of man there is no evidence to
show ; but there are trees of other kinds of large size, as
depicted and described in the report referred to. They are:
Calophyllum Inophylliim (Guttiferse), Morinda citrifolia
(Rubiaceae), Cordia subcordata (Boragineae), Pisonia grandis
(Nyetaginaceae), and a screw pine, probably the widely spread
Pandanus odoratissi?nus. One of the illustrations is a most
effective representation of a group of screw pines. The
Cordia is perhaps the commonest tree, and is most con-
spicuous, having a spreading crown with branches down to
the ground. Pisojiia grandis is described as forty or fifty
feet high, with a trunk four feet in diameter ; dimensions
one would hardly have expected. I have drawn some-
what freely from this report, because it is by far the most
instructive known to me.

A more recent contribution to island literature by Mr.
C. M. Woodford (4) is equally deserving of attention,
though wanting illustrations. It deals with the Gilbert
Archipelago, one of the most remarkable of the numerous
groups in the Eastern Pacific. There are sixteen islands,
not counting the islets of the atolls, forming a chain, trend-
ing from north-west to south-east and extending from about
3° north to 30 south latitude in 1730 to 1 77° east longitude.
Eleven out of the sixteen are of atoll formation, and the
largest of them is little more than twenty miles long and
twenty feet high in the highest part. They are mostly
inhabited, and the population half a century ago was
estimated at 50,000, though it has since dwindled down to

INSULAR FLORAS. 289

probably a quarter of that number. The presence of so
large a population must have had some modifying influence
on the vegetation ; yet not to the extent that might have
been expected, because there is little cultivation, the natives
living largely on fish, with which the waters swarm. Mr.
Woodford says : " The islands are clothed from end to end
with a dense growth of cocoanut palms and other vegeta-
tion, and present a beautiful appearance when approaching
from the sea. The reefs and lagoons teem with fish, thus
enabling the islands to support a population which for
their land area was at one time equalled in no part ot the
world."

Mr. Woodford gives a list of the plants compiled from
observations on the islands he visited, which he believes is
nearly complete. As I am able to supplement it by a few
additional species in the Kew Herbarium, chiefly collected
by the Rev. Mr. Whitmee, and also to supply specific names
in some cases where he gives only the generic, I will give a
list of all the vascular plants known to inhabit the group, as
a sample of the typical coral island flora. Calopkyllum
Inophyllum (Guttiferae), Sidafallax (Malvaceae), Triiunfetta
procumbens (Tiliaceae), Tribulus cistoides (Zygophyllacese),
Pemphis acidula (Lytheraceae), Rhizophora mubronata
(Rhizophoraceae), Guettarda speciosa and Morinda citrifolia
(Rubiaceae), Sccevola Kcenigii (Goodeniaceae), Tournefortia
argentea (Boraginaceae), Pisonia biennis and Boerhaavia
^fksYZ (Nyctaginaceae), Euphorbia Atoto? (Euphorbiaceae),
Ficus tinctoria (Moraceae), Crinum pedunculatum ? (Am-
aryllidaceae), Cocos nucifera (Palmaceae), Pandanus odora-
tissimus (Pandanaceae), Fimbristylis glomerata (Cyperaceae),
Lepturus repens (Gramineae), and Polypodium Phymatodes
(Filices) — just a score of species, it will be seen, belonging
to as many different genera, and to eighteen different natural
'orders of the most diverse habit and structure. They
are almost without exception plants of general distribution
in tropical oceanic islands and on the sea-shores of the
continents. The majority of them indeed inhabit the
smaller remote islands of the tropical parts of the Indian
Ocean. I will only add here that their seeds are such as

2go SCIENCE PROGRESS.

are transported by oceanic currents, birds, and winds, with-
out destroying their vitality. In another article I pro-
pose discussing these agents of dispersal in some detail.
The absence from the above list of the two largest natural
orders — Leguminosae and Compositse — may cause some
surprise, especially as the seeds of many of the former bear
long immersion in salt water with impunity, and the pappose
achenes of the latter are often, it is assumed, conveved
lont{ distances bv wind. Le^uminos£e are rare in all
oceanic islands, both coral and volcanic ; but Composite,
on the other hand, are characteristic of many volcanic
islands, the Galapagos and St. Helena, for example.

The distribution of the plants of the Tonga or Friendly
Islands has been worked out by the writer (5), and a few
of the most interesting facts may be repeated here. This
group lies to the south-east of Fiji, between 180 and 230
south latitude, and 1730 and 176° west longitude, and com-
prises both volcanic and coral islands ; some of the former
being considerably larger than those of the Gilbert Group,
and rise to altitudes of 500 to 3000 feet. Fuller informa-
tion on the geology of the islands will be found in an article
(6) by Mr. J. J. Lister. But although the Tonga Islands
are considerably larger than the Gilbert Islands, it is more
in land area and altitude than external dimensions, and
it is due partly to the absence of central lagoons. Ton-
gatabu in the south, the largest of the group, is about
twenty-two miles in its greatest length, and is composed
entirely of coral limestone. This island is the best known
botanically ; but Mr. ]. J. Lister, whose collections were
worked out for my paper referred to above, thoroughly ex-
plored the neighbouring smaller, though more elevated,
Eua, which gave a considerable number of additional
species. Since the publication of my paper, Kew has
acquired a collection of dried plants made by Mr. C. S.
Crosby in the Vavau cluster in the north. This collection
has not yet been thoroughly worked out, but although
it doubtless contains some additions, they will not be of a
character to modify what has been written respecting the
affinities of the flora of the whole group. The total num-

INSULAR FLORAS. 291

ber of assumed indigenous species of vascular plants in
my enumeration is 290, whereof 246 have a westward, and
220 have an eastward extension in Polynesia; 138 are
Australasian (Australia, New Zealand and outlying islands),
162 are Malayan, and at least 150 have a wider range
either in the Old or New World, or in both. From the
foregoing figures it will be seen that the Bora of the
Tonga Islands is largely composed, like the very small one
of the Gilbert Islands, of species of wide distribution.
Indeed no genus is peculiar to the group, and only ten
species so far as our present knowledge goes are endemic,
and a more complete exploration of the Fiji Islands and
other neighbouring groups may reduce this number. The
290 species of the Tongan flora represent no fewer than
202 genera and seventy-nine natural orders out of the 202
recognised in Bentham and Hooker's Genera Plantarum.
The proportions are 2*55 genera to an order, and 1 '43 species
to a genus in the Tongan flora. In the flora of the world
the proportions I obtained by a very rough calculation are
37 '5° genera to an order, and 12*65 species to a genus.
Taking the number of Tongan species (138) which extend
to Australasia, one might overestimate the affinities, be-
cause, as a matter of fact, a large proportion of these species
have a wide range. Indeed only a dozen species have
decidedly Australasian connections. These are : Melicytus
ramiflorus, Ratonia stipitata, Metrosideros polymorpha,
Jasmirmm simplicifolium, Hoya australis, Iponuea congesta,
Pisonia inermis, Peperomia leptostackya, Euphorbia Spar-
mannii, Ficus aspera, Podocarpus elata and Pteris comans.
It will be perceived that the connections are specific rather
than generic. But the most significant facts brought out
in the paper under consideration are two, namely, the
large proportion of species — upwards of a third — peculiar to
Polynesia, and the strongly Malayan character of the flora,
generally, of the Tonga, Fiji and Samoa Islands.

Several additional small contributions to the flora of
the Solomon Islands have appeared (7), including some
highly interesting novelties collected by the officers of
H.M.S. Penguin, and the Rev. R. B. Comins. Excellent

292 SCIENCE PROGRESS.

photographs of the singular new genus Sararanga
(Pandanaceae) have been received at Kew, as well as ripe
fruit in spirit, which will enable me to add to my published
description, though not to complete it, because the male
inflorescence is still unknown. Two species of Begonia, an
Oxymitra (Anonacese) with flowers nearly nine inches long,
a singular Tabernce Montana having a twisted fruit, and
the anomalous genus Lophopyxis (8) are among the latest
additions to the flora of the Solomon Islands. The last is
doubtingly placed in the Euphorbiaceae by Sir Joseph
Hooker, and it has since been twice described (9 and 10),
and placed in different natural orders, namely, Combretopsis
(Olacinese) and Treubia (Saxifragaceae). There are two
or three very closely allied species or races inhabiting
Malacca, Ceram, New Guinea, and the Solomon Islands.
I may refer in passing to a zoological paper (11) in which
the author puts forward the theory of a former connection
of the Solomon, Fiji, New Hebrides, Loyalty, New-
Caledonia, Norfolk and New Zealand Islands with New
Guinea, but not with Australia. That there was, in the
remote past, a greater land area in this region seems
highly probable, but the relationships are so complex that
fuller data are required to afford a solution of the problem.
The present flora of Lord Howe Island, described a few
pages forward, does not favour Mr. Hedley's views in their
entirety on this point.

In my reference to the flora of Christmas Island (12) I
overlooked a paper that supplemented mine to some extent
(13), especially in relation to the vegetation.

Dr. Trimen (14) has published two more volumes of
his admirable flora of Ceylon, bringing it down to the end
of the Balanophoraceae, following the arrangement of
Bentham and Hooker's Genera Plantarum. The same
author has drawn up a provisional list (15) of Maldive
plants ; the first, I believe, that has appeared. As might
be expected there is no endemic element, and the vegeta-
tion is an assemblage of the ubiquitous coral island plants
and weeds of cultivation. Dr. Trimen makes no mention of
the Cocos maldivica or Coco-de-mer (Lodoicea sey die liar inn) \

INSULAR FLORAS. 293

but, although it is improbable that this palm ever grew in
the Maldive Islands, something yet remains to be done to
complete its history. John de Barros, a Portuguese
author, is thus quoted (16) by the writer of an article on
these islands : —

"Their productions he also enumerates minutely, especially
the coconut, both of the ordinary kind and of that called
coco-de-mer, almost peculiar to the Seychelles, the seed of
which appears to have been borne thence to the Maldivas
by the currents of the ocean ".

Since the publication of my notes on the flora of New
Zealand and the outlying islands (17) several interesting
papers on the subject have appeared, though there is only
one of sufficient importance to call for more than brief
mention. But first the minor ones. Mr. F. Kirk is the
author (18) of a series of monographs treating of the
genera Gentiaua, Colobatttktis, and Gunnera, as re-
presented in the New Zealand region, besides descriptions
of a number of new species belonging to various natural
orders. The forms of Gentiana are numerous, and the
species exceedingly difficult of delimitation. Kirk defines
ten species, and about half of them comprise several
varieties. They are spread all over New Zealand, except
the extreme north, and they extend to the Chatham,
Antipodes, Auckland and Campbell Islands ; but hitherto
no species has been found in Macquarie Island, the southern-
most of these islands. They chiefly inhabit the mountains,
in alpine and subalpine situations, and the sea-coast ; four
out of the ten, it is stated, not being found out of the reach
of the sea-spray. They all belong to one group, char-
acterised by having pentamerous flowers, unappendaged
corollas, and versatile anthers. White is the prevailing
colour of all the species, though some of them occasionally
exhibit various shades, mostly dull, of red, purple, and violet,
and more rarely a pale yellow. This is in direct contrast to
the behaviour of the northern species, speaking generally, and
we are indebted to Mr. Kirk for the observation. Colo-
banthus (Caryophyllaceae) is one of those densely tufted
moss-like genera of which there are representatives in

294 SCIENCE PROGRESS.

various natural orders. It is one of the very few genera
common to Australasia, to the Antarctic, and other southern
islands, and the Andes, and confined to these regions. One
species, C. quitensis, ranges from the mountains of Mexico
to Cape Horn and reappears in New Zealand. Kirk also
records it from Amsterdam Island, but that seems to in-
volve two errors, for, so far as our data at Kew go, C.
diffusus inhabits St. Paul, and no species is found in the
neighbouring island of Amsterdam. One species, C.
Billardieri, is found in the Alps of Victoria, in Tasmania, New
Zealand, and the small islands southward to Macquarie. Two
Falkland Islands species also recur in South Georgia, the
southern insular limit of phanerogamic vegetation in the Pata-
gonian region, if we except a grass, Aira antarctica, collected
by Dr. Eights in the South Shetlands, about 620 S. lat., or
8° south of South Georgia. Kirk enumerates and de-
scribes ten species of Colobanthas from the New Zealand
region, including four proposed new ones.

Gunnera (Haloragidacea^) has a similar range to that
of Colobantkus, save that it does not reach the colder limits
either in America or the New Zealand region. Kirk
brings up the species of the latter region to nine, four of
which are new.

W. Colenso, D. Petrie, and H. C. Field also describe
a few novelties (19), and the first named gives a charming
description of his travels and botanising in the romantic
country around Hawke's Bay, upwards of fifty years
ago.

The one paper which I propose to discuss a little more
in detail is devoted to the natural history of Macquarie
Island (20), the most southerly speck of land in the New Zea-
land region known to support phanerogamic vegetation. It
is in the same latitude (540 S.) as South Georgia in American
waters, the flora of which I have described (21), where a
list is given of the vascular plants inhabiting the island.
They are separated from each other by about 164° of
longitude, which in this latitude means, in round numbers,
5875 geographical miles ; yet, as previously stated, nine
out of thirteen of the vascular plants found in South

INSULAR FLORAS. 295

Georgia also occur in some of the southern islands in the
New Zealand region. Later on I shall have something-
to say, or rather repeat, in explanation of this fact. It
should be noted that these islands are in about the same
latitude as York in England ; yet the climate is now so
severe in South Georgia and other conditions are so un-
favourable to vegetation that the flora is perhaps poorer
than in the highest northern latitudes yet explored, and
entirely wanting the colour characteristic of many northern
flowers. For example, such charmingly beautiful plants as
Papaver nudicaule, Silene acaulis, Saxifraga oppositifolia
and Epilobium latifolium are found north of the eightieth
parallel ; whereas the showiest flowers in South Georgia are
those of a very small buttercup, so small indeed that they want
finding. The flora of Macquarie Island is, however, not
altogether devoid of colour, as witness Pleurophyllum ; and
Stilbocarpa is remarkable for its large rhubarb-like leaves.

Macquarie Island is between twenty and twenty-five
miles long and five or six miles across in its broadest part.
It is generally hilly, though the hills are nowhere above
800 feet. The following is a list of the vascular plants
recorded by Mr. Hamilton (20), who visited the island
early in 1894. I may mention that I had most of these
plants under observation (22), and I do not agree in every
instance with his and Mr. Kirk's (23) determinations ; but
the divergencies are unimportant ; and there are several
corrections of the names given in previously published lists.
Ranunculus ci-assipes, Cardaminc hirsuta, var. corymbosa,
Colobanthus muscoides, C. Billardieri, Stellaria decipiens,
Mont ia font ana, Aceena Sanguisorbcz, A. adscendens, Calli-
triche a7itarctica. Epilobium nummularifolium, E. lin-
nceoides, Azorella Selago, Stilbocarpa polaris, Coprosma
repens, Cotula plumosa, Pleurophyllum Hookerii, Uncinia
nervosa, Luztila criuita, Deschampsia Hookeri, D. penicil-
lata, Poa foliosa, P. Hamiltonii, Agrostis antarctica,
Festuca contracta, Aspidium aculeatum, var. vest it um Poly-
podium aust?'ale, Lomaria alpina and Lycopodium Billar-
dieri, var. varium. The last named one would have
hardly expected to find in so high a latitude, where the

296 SCIENCE PROGRESS.

only woody plant is the small creeping Coprosma repens,
because it usually grows on trees. A re-examination
of a very small collection of Macquarie Island plants
sent by Mr. Fraser of the Sydney Botanic Garden to the
late Sir William Hooker, about sixty years ago, has led to
the discovery of Lycopodium Selago, associated with Azor-
ella Selago, a very similar plant in external appearance. In
addition to the foregoing there are three colonised vascular
plants, namely, Stellaria media, Cerastium triviale and Poa
annua ; and Mr. Hamilton states that he also collected
Tillcea muscosa and two sedges, but the specimens were
lost. If we except three imperfectly known grasses, which
Mr. Kirk has described as new (24), there are no endemic
plants in the island. The vascular cryptogams are all
widely spread, two of them recurring in the northern hemi-
sphere. Of the flowering plants upwards of half are confined to
the New Zealand region, and the rest have a wider range.
Stilbocarpa polaris ( Aral iacese) and Pleurophyllum Hookerii
(Composite) are the two most remarkable and most con-
spicuous plants in this meagre flora ; the former having
large rhubarb-like leaves, and the latter silky, silvery leaves
and handsome purple flower-heads in long racemes. Colo-
banthus, Azorella, Acczna and Uncinia are equally charac-
teristic in the South American region.

Quite recently a fresh account of Lord Howe, Pit-
cairn and Norfolk Islands has appeared (25), but it con-
tains nothing new on the botany of these islands. Special
stress is laid on the beauty of the vegetation of Howe
Island, where palms and tree ferns abound, and fig-trees of
the banyan type attain dimensions hardly exceeded else-
where. What is known, however, of the botany of this
interesting island has appeared in Government Reports and
scattered in a variety of publications (26-29) of limited
circulation. It is true that Sir F. von Mueller long ago
published (30) a bare list of all the plants known to him
from the island, but it is incomplete, and supplies no in-
formation beyond the names of the plants. This being so,
I am preparing a detailed account of the flora of this island
with a view to publication elsewhere. I may here give,

INSULAR FLORAS. 297

however, some particulars gleaned from the publications
referred to, though they are mostly anterior to the date
(1885) to which I have limited myself generally in these
articles, adding a few remarks of my own on the distribu-
tion of the plants.

Lord Howe Island is of small extent and peculiar con-
formation, situated about 300 miles from the coast of
New South Wales in 310 35' S. lat. It is seven miles
long with an average breadth of one mile, and the steep
circular flat-topped elevations rise to a height of nearly
3000 feet. Norfolk Island, the nearest land to the north-
east, is about 500 miles distant, and New Zealand, to the
south-east, somewhat farther off. The island is of volcanic
origin, consisting of three basaltic masses connected by
coral-sand rock. About 165 species of indigenous flower-
ing plants are known, and forty-eight ferns and lycopods.
As already indicated palms form a conspicuous feature in
the scenery. There are four species, all endemic, and
they have been very much named, though three out of
the four are well known under the generic name of Kentia.
They are K. Belmoreana, K. Canterburyana and K. For-
steriana — names familiar to many persons, as they have
long been favourite palms in cultivation on account of their
elegance and hardiness. A tall and graceful specimen of
K. Forsteriana is one of the finest ornaments of the central
part of the palm-house at Kew. The fact of there being
a good market for the seeds of these insular palms has led
to considerable destruction of the trees to obtain them ; but
I believe the Government of New South Wales has made
it a punishable offence to destroy trees on public territory.
Beccari (31) has founded the genus Howea for them, which,
if accepted, is the only endemic one. There are also four
indigenous tree ferns, three of which are endemic. But the
banyan trees {Fiats columnaris) are perhaps the most
striking objects in the vegetation. Several appear in the
photographs illustrating Wilson's Report, one of which is
said to cover an area of three acres ! Morcea Robinsoniana
is an outlying gigantic member of an African genus of

Irideae very closely allied to Iris itself. It is known as the

21

298 SCIENCE PROGRESS.

wedding-flower, and there is a fine specimen of it at the
south end of the cactus-house at Kew. Carmichcelia exul
(Leguminosae) is the only species of a considerable genus,
with this exception, not known to inhabit any other country
than New Zealand. There are other connections with the
flora of the latter country, but they are mostly such as extend
to Australia as well. Pimelea longifolia and the handsome
sedge, Gahnia xantkocarpa, are apparently exceptions. In
round numbers 25 per cent, of the species of flowering plants
of Lord Howe Island are endemic, and 62 per cent, are
common to Australia, many of these having a wider
range. A few are common only to Australia, New Zealand,
and Norfolk Island. The shrubby violaceous genus
Hymenanthera is an example. The gum trees {Eucalyptus)
of Australia are represented by the endemic Acicalyptus
Fullagari, a small Fijian genus differing from Eucalyptus 'in
having a calyptrate calyx-limb and separate petals. Two
other conspicuous trees in the endemic element are Draco-
phyllum Fitzgeraldii (Epacridese) and the screw-pine, Pan-
danus Forsteri. The former is a tree, said to be the largest
in the order, attaining the height of fifty to sixty feet. It has
the foliage and aspect of a monocotyledon rather than of a
dicotyledon. One characteristic Australasian type we miss
in the Lord Howe Island flora, and that is Cor dy line.

When reviewing (32) the newer literature relating to
the flora of the Galapagos Islands I found little to add to
what had been done by Darwin, Hooker and Andersson ;
merely mentioning the visit of the United States ship
Albatross, and Dr. G. Baur's theory of the origin of the
fauna and flora. Since then an account of Dr. Baur's
botanical collections has been published (33), and the sub-
stance has also appeared in an English journal (34), and
Dr. Baur himself has written (35) and lectured (36) in
defence of his theory of the origin of this group of islands.
As previously stated, he contends that the evidence points
to the present condition being the result of subsidence ;
that the islands were formerly connected with each other
and at a still earlier period with continental America.
Although this theory has been derided, I think the biologi-

INSULAR FLORAS. 299

cal data strongly favour its correctness, and the soundings
given in the map accompanying Agassiz's report (2,7) of
the Albatross expedition show a relatively shallow area
in which the Galapagos Islands are situated, and which
extends eastward to the mainland of Veraguas. Probably
the separation would be greatly anterior to the segregation
of the West Indian Islands.

In the Botany of the Challenger expedition (38) I
attempted a rough classification of islands in relation to the
composition of their floras. These are defined as follows :
1, Vegetation comprising a large endemic element including
distinct generic types ; 2, vegetation comprising a small,
chiefly endemic element, the derivation of which is easily
traced ; and 3, vegetation containing no endemic element.
Without due consideration the Galapagos were referred to
the first category. Sir Joseph Hooker (39) fully realised
the absolute American affinities of the flora ; but he analysed
and discussed it as a derived one rather than as a remnant.
Darwin, through some misinterpretation of the statistics sup-
plied to him, fell into a singular error respecting the generic
endemic element in the Galapagos (40). Referring to
the Compositse, he says : " There are twenty-one species,
of which twenty are peculiar to this archipelago ; these
belong to twelve genera, and of these genera no less than
ten are confined to the archipelago ! " How this error arose
it is impossible to say, but as a matter of fact the statement
quoted is wrong (and was wrong at the time it was written)
in all its details. With regard to assumed endemic genera
of Compositae, five were founded on galapageian plants,
namely, Microcoecia and Desmocephalum, since reduced to
Elvira ; Macrcea to Lipochczta ; and Scalesia and Lecocar-
pus are so near to Mirasolia and Melampodinm respectively
that the late Mr. Bentham gave it as his opinion that they
might well be reduced. Two genera from these islands
belonging to other orders have also been reduced. These
are Galapogoa = Coldtnia (Boraginacae), and Dictyocalyx
= Cacabus (Solanacese) ; and Pleuropetalum (Amarantaceas)
has since been found in several localities in Western
America. Taking this view of their affinities, there is not

3oo SCIENCE PROGRESS.

a single genus of flowering plants endemic in the Galapagos ;
but each island has its distinct species. Briefly put then,
the genera are the same in all the islands, and the genera
are American ; whereas a large proportion of the species
are peculiar to each island, though they are not so ex-
clusively confined to single islands as Darwin supposed.
On this point he says (41) : " Again Euphorbia, a mundane
or widely distributed genus, has here eight species of which
seven are confined to the archipelago, and not one found on
any two islands. Acalypha and Borreria, both mundane
genera, have respectively six and seven species, neither of
which genera has the same species on two islands, except
in the case of one species of Borreria." Dr. Baur's
recent explorations necessitate a considerable modification
of this statement ; yet in a sense they confirm and empha-
sise it. Baur himself deals more particularly with the fauna
(36) in illustration of this phenomenon. More than 400
specimens of the lizard genus Tropidurus were collected,
and in the result he found that "each island possessed only
a single species ; all the individuals of an island belonged
to one species ; and nearly every island had its peculiar
species or race ".

The botanists who worked out Dr. Baur's collections
selected Euphorbia viminea (33) as an example of a plant
exhibiting racial differences in each of the eight islands,
where it is now known to occur. The genera Acalypha
and Borreria are cited as other instances. On the other
hand, Euphorbia articulata, which was collected on four
different islands, showed no such tendency.

In a former article in this journal (32) I mentioned the
fact that huge branching Cactacese form one of the most
striking features in the lower zone of the vegetation of the
Galapagos, and I have elsewhere (42) given some par-
ticulars of what is known, and how little is known of these
Cactaceae ; and I may repeat here that specimens of only
one species have, so far as I can ascertain, been brought
away from the islands. These were brought to this country
by Darwin, and published by Henslow (43) under the
name of Opuntia galapageia. This species is remarkable

INSULAR FLORAS. 301

in the genus for its very small flowers, which are only about
three-quarters of an inch in diameter, and also for the small
number of petals ; but as the figure was made from dried
specimens, it may be inaccurate in some details. In the
same place it is mentioned that a species of Cereus was
common in the island, but was not found in flower.

Darwin himself specially alludes (44) to the prominent
feature these Cactacese are in the landscape, and likewise
to the fact that they grow in the rough lava where there is
absolutely no other phanerogamic vegetation. He further
points out their importance as food for the gigantic tor-
toises and land lizards. They are also a source of water
during the severe droughts, which often parch the lower
zone.

Subsequent travellers have dwelt upon the part the
Cactacese play in the biology of the island, and Andersson,
a botanist who visited the islands in 1852, states (45) that
he observed four or five species, but had time neither to
prepare specimens nor sketch the plants.

My note on the subject in Nature came under Dr.
Baur's notice, and he forwarded me two photographs, one re-
presenting a fine example of an arboreous Opuntia of great
size, and the other a view embracing a number of large
Cerei, together with a transcript of his notes on the subject
in a paper (46) which I had not seen. He was struck by
the difference in the appearance of the Optmtice on the
different islands, and observed that the large Opuntia has
a different habit on nearly every island. Thus, on Barring-
ton, Indefatigable and South Albemarle, it develops a
very tall stem ; on Charles and Hood a relatively short
but thicker stem ; on Jervis a very short stem, branch-
ing from very near the ground, and on Tower Island
it forms no stem at all, and appears as a dwarf bush.
Dr. Baur attributes these modifications to the varying degrees
of humidity, the greatest development occurring in the driest
climate. In the lower region of South Albemarle, up to
about 500 feet, the Opuntia is very common, attaining a
large size, the largest being about twenty feet high, with a
trunk two feet in diameter. " In old trees the bark looks

302 SCIENCE PROGRESS.

very much like that of a pine, and peels off in very thin
sheets."

The common Cereus, which strongly resembles C.
peruvianus, attains almost the same dimensions ; but this
is all we know about it at present, and there is clearly
much more botanical work to be done in the Galapagos
before the subject is exhausted. It may be of interest to
add that no species of cactus inhabits the island of Juan
Fernandez, but this may be ascribed to climatic differences.
Indeed, so far as is known, none of the other Pacific American
islands, at any considerable distance from the coast, support
any members of the order, though Malpelo, for example,
is barren enough to give them a chance of flourishing.

Another remarkable element in the flora of the Galapagos
is the relatively large number of species of the small order
Amarantacese. About fifteen species are now known to in-
habit the islands, and twelve of them are endemic. They
belong mainly to the genera Telautkera, Alternanthera,
and Froelichia.

Concerning the flora of the Arctic Islands in relation to the
adjacent continents, I have to add a few references (47-48)
to works of older date than my paper (49), and a few recent
ones of unusual interest. Mr. Trevor- Battye's account of
the vegetation of Kolguev Island (50) and Colonel Feilden's
contributions on the subject (51-52) rank first among these.
The former noted ninety-five species of phanerogamia in
Kolguev, and his observations on the vegetation are of
great value. About a score of the plants recorded by
Ruprecht (53) were not found, and Trevor-Battye remarks
on the absence of Saxifraga oppositifolia, Mertensia maritima
and Ledum palustre. Colonel Feilden's short paper on
Spitsbergen plants, as well as his remarks on mild arctic
climates, is worthy of attention on account of his experience.
The only information I have found (54) respecting the
vegetation of Einsamkeit Island is that there is no grass
carpet, and it is added that there is a great quantity of drift-
wood, sometimes far inland. A new list (55) of Iceland
and Faeroe plants does not claim to be anything more than
a contribution to local distribution.

INSULAR FLORAS. 303

There is little new literature relating to the Atlantic
Islands, but Sir Joseph Hooker's comparison (56)
of the Maroccan and Canarian floras was overlooked by me
when reviewing the writings of Dr. Christ. In an article
(57) of more recent publication, the latter gives expression
to a considerable modification of his views on the affinities
of the Canarian flora. He now recognises a much more
intimate connection with the old African flora. But I must
not reopen the subject here.

One important contribution (58) to the flora of the West
Indies has appeared. This part consists of a critical
elaboration of the Myrtaceae, than which there was probably
no group of plants more in need of revision. It is some-
what appalling to see such familiar trees as the allspice and
clove with a page and half of synonyms each ; yet it is
very useful, historically, as well as for practical purposes, to
have them brought together.

W. BOTTING HEMSLEY.

(To be continued.}

THE PRESENT POSITION OF THE CELL-
THEORY.

(CONCLUSION.)

THUS far I have tried to rehabilitate the cell as a vital
unit. I have now to deal with the further question as
to the part played by the cell in the composition of the higher
animals and plants. In the earlier part of this essay I
stated that Mr. Adam Sedgwick denied in toto the proposi-
tion that "the elementary parts of all tissues are composed
of cells ". Since writing those words, Mr. Sedgwick's reply
to my previously published criticisms has appeared,1 and I
find that I have made a mistake. For he does not deny
the proposition, but says: ''The assertion that organisms
present a constitution which may be described as cellular is
not a theory at all ; it is — having first agreed as to the
meaning and use of the word cell — a statement of fact and
no more a theory than is the assertion that sunlight is com-
posed of all the colours of the spectrum ". I can only beg
Mr. Sedgwick's pardon. I certainly was led to suppose
from his earlier writings that he regards the cell as a
nonentity, in so far as it may be considered to be the
ultimate structural unit of the metazoa, and I recoiled from
his suggestion that the essence of development lay in "a multi-
plication of nuclei and a specialisation of tracts and vacuoles
in a continuous mass of vacuolated protoplasm ".

Mr. Sedgwick now explains that he objects, not to the
statement that tissues are composed of cells — or, in his own
words, that they have a composition which may be described
as cellular — but to the statement that an individual meta-
zoon is an aggregate of lesser individuals, or, as it has often
been expressed, a cell colony or cell republic. I have else-
where— and as Mr. Sedgwick well says, after great effort —
come to agree with him on this point, for a careful survey
of a considerable range of facts led me to the conviction

1 Adam Sedgwick, "Further Remarks on the Cell-Theory, with a Reply
to Mr. Bourne," Quart, four. Micr. Sci., vol. xxxviii., p. 331, 1895.

THE PRESENT POSITION OF CELL-THEORY. 305

that the idea of a cell republic was inappropriate. Such
being the case I would willingly have buried the hatchet,
but when I had already dug the hole to bury it in, my hand
was stayed by some criticisms on his views and on mine
which have just been published in a contemporary periodi-
cal.1 These criticisms have restored to me the conviction
which I held when I ventured to write a criticism of Mr.
Sedgwick's views ; a conviction that, as he originally
expressed them, they were calculated to mislead and to do
harm to the very cause whose interests he was desirous to
promote. As he has lately explained that he did not mean
what I supposed him to mean, there is no need for quarrel-
ling any further with him, but he will himself allow that I
was amply justified when I gave the following as a not
unfair statement of his position. That from the connection
known to exist between some cells composing adult tissues,
there is an antecedent probability that similar connections
exist between all cells composing all tissues ; and this
probability is heightened by observations made on the
development of Peripatus, by the fact that the so-called
mesenchyme cells in Avian and Selachian embryoes are
continuous and not isolated as was once supposed, and by
a study of the developing nerves of Elasmobranchs. And
that it follows from this that the morphological concept of a
cell so far from being of primary is altogether of secondary
importance, and that progress in the knowledge of structure
is impossible so long as men persistently regard cells as the
fundamental structural units on which the phenomena mani-
fested by organised beings depend. The true method of
inquiry must be a study of the growth, extension, vacuolation
and specialisation of the living substance protoplasm.

He has been understood by others as I understood him,
and indeed he had so expressed himself that he could
scarcely have been understood otherwise. What I had
anticipated has happened. Persons, ready to grasp at
novel ideas, have said in their hearts : "Tush, there is no cell !
There are protoplasmic masses which may contain one or
many nuclei ; the mass is of no importance, it is scarcely

x Natural Science, vol. vii., No. 46, December, 1S95.

306 SCIENCE PROGRESS.

more than the medium in which the nucleus lives, and
through which it exhibits its powers. The nucleus may
move about in the mass, acquiring ' spheres of influence '
at its halting places, and so producing the vital phenomena.
It is the nucleus which is the vital unit, and there is no
bond between nucleus and cytoplasm which shall compel
us to regard their union as the necessary condition of living
individuality."

I have made use of my own expressions, but if this is not
the plain meaning of the short editorial entitled "The
Reign of the Nucleus" in the January number of Natural
Science, what is ?

The writer of the editorial is so captivated with the pros-
pect opened up by his interpretation — a perfectly legitimate
interpretation — of Mr. Sedgwick's writings, that he forthwith
abolishes the existence of cells altogether and talks glibly
of " protoplasmic masses," ignoring the fact that the masses
in question are divided up into corpuscles. Following up
his theme of protoplasmic masses dominated by nuclei, he
lightly dismisses the arguments which I put forward,
saying that the segmentations of Nereis, Unio, etc., exhibit
nuclear lineage rather than cell lineage (who could
hold such an opinion after a careful study of Wilson and
Lillie's figures ?), and winds up with the following astonish-
ing piece of criticism : " In drawing an argument for the
cell-theory from the definite places assigned to cells in
development Bourne seems to us to have overlooked the
experiments of Wilson, Driesch and Hertwig, who have
shown that the nuclei may be moved about in the proto-
plasmic mass almost as freely as a ' heap of billiard balls
may roll over each other ' ". I rubbed my eyes and
wondered. I thought I knew the works of Driesch,
Hertwig and Wilson pretty well, and that I had considered
them carefully, and I had certainly regarded them as strong
evidence in favour of the cell-theory as I conceived of it.
A short search soon hit upon the passages which are
professedly quoted. First for Driesch : x " Die Furchungs-

1 Hans Driesch, Entwicklungmechanischse Studien, iv., Zeitschrift fUr
IViss. Zoologie, vol. Iv., 1893.

THE PRESENT POSITION OF CELL-THEORY. 307

kugeln der Echiniden als ein gleichartiges Material
anzusehen sind, welches Man in beliebiger Weise, wie
einen Haufen Kugeln durch einander werfen kann, ohne
dass seine normale Entwicklungsfahigkeit darunter im
Mindesten leidet ". (The segmentation spheres of Echinids
are to be regarded as a homogeneous material which one may
roll amongst one another at will like a heap of balls, without
thereby destroying in the least their capacity for develop-
ment.) No hint whatever of rolling the nuclei through the
protoplasmic mass. The statement is made of Furchungs-
kugeln, that is of cells, and it is the cells that one may roll
about like balls. Not a bad argument for my contention,
that the blastomeres of many developing ova are disjunct.
If there were any doubt as to Driesch's words a study of
figures 39-68 which illustrate his paper would satisfy the
most exacting. The blastomeres are unusually distinct
from one another, especially in the embryoes illustrated by
figs. 63 and 67. Now for Hertwig:1 "Bei den verschiedenen
Modificationen des Furchungsplasma werden die aus dem
ersten Furchungskern durch aufeinanderfolgendeTheilungen
erzeugten Kerngenerationen Theilen des Dotters, die in Eir-
aum eine sehr verschiedene Lage einnehmen, zuoetheilt und
mit ihnem zu einem zellkorper verbunden. Die Kerne wer-
den in Eiraum wie ein Haufen von Kugeln durch einander
gewurfelt." This is a very complicated German sentence
and might well lead to a misunderstanding, but it comes out
all right in plain English. "In the various modifications of
the divisional processes the nuclear generations, which are
produced by successive divisions from the segmentation
nucleus, are assigned to a portion of the yolk which occupies
very different positions within the limits of the egg, and are
bound with it to form a cell body. The nuclei are rolled
one over another within the limits of the egg like a heap of
balls." This passage is a summary of preceding state-
ments and inferences, and it might be held to bear a very
different meaning to that which it does bear ; the illustration

1 O. Hertwig, " Ueber den Werth der ersten Furchungszellen fur die
Organbildung der Embryo," Arch, fur Mikr. A nat., vol. xlii., p. 662, 1893.

308 SCIENCE PROGRESS.

of the heap of balls is a very loose one. To understand
the meaning of the summary one must turn to pp. 678-685
of the same memoir, which consist of a section entitled
" Erklarung des abnormen Furchungsverlaufes ". There
we learn, as we had previously learnt from Driesch, that
the divisional planes of segmenting ova are determined by
the direction of the nuclear spindles and that the orientation
of the first nuclear spindle is determined by the character of
the body of the ovum and its contents. The ova of Echinus
are homogeneous throughout, and orientation of the first
nuclear spindle is a chance affair. But the ovum of the
Frog is not homogeneous ; it consists of a smaller cap of
protoplasm resting on a large body of yolk, and the nucleus
lying in the cap of protoplasm, the direction of the first
nuclear spindle is determined by its relations to the more
active yolk on the one hand, and the denser food yolk on
the other. The relations of the food yolk and protoplasm
are changed by the pressure applied during the experiments
and the changes are different according as the pressure is
applied vertically or horizontally. Hence the direction of
the first and the succeeding nuclear spindles is changed
in different senses, according to the pressure employed. As
the divisional planes are always at right angles to the
nuclear spindles, the positions of the two first and the suc-
ceeding blastomeres differ according as the pressure applied
is vertical, horizontal, oblique, or circumferential. One may
in fact cause the blastomeres and their contained nuclei to
take up what position one will by varying the direction of
the pressure. In this sense, and in this sense only, can one
speak of rolling the nuclei about like balls. Not a word about
a protoplasmic mass through which the nuclei are caused to
roll. On the contrary, a great deal about planes of division
and splitting up of the egg into corpuscles round the nuclei.
It only requires a glance at Hertwig's figures and diagrams
to show that the blastomeres are as distinct during abnor-
mal division as during normal division, and that there is not
at any time any question of a "protoplasmic mass," a cir-
cumstance which has been well understood by everybody
who has taken the trouble to read his memoir carefully.

THE PRESENT POSITION OF CELL-THEORY. 309

Most of the experiments of Wilson, Hertwig and
Driesch were of a different kind. They isolated the blas-
tomeres by gentle shaking. Driesch is very careful to say
gentle ; rough shaking destroyed the individual blastomeres.
Things which are so loosely united as to be separated thus
easily from one another scarcely suggest the nature of a
coherent protoplasmic mass.

The criticism falls entirely to the ground and one can
only wonder how any one could have had the temerity to
make it. The very objections urged to my views are but
additional evidence in support of them, and I was well
aware that the evidence existed when I wrote, but I had to
be as brief as possible, and did not refer to it. My state-
ment that it is very clearly established that there are
numerous cases in which there is not "a primitive con-
tinuity which has never been broken" is abundantly
justified. Mr. Sedgwick wonders why I emphasised the
distinction and complete isolation of the cells formed by
the segmentation of the egg. The reason is surely clear
enough. Because he suggested, in no uncertain manner in
his earlier writings, that the connections between adult cells
were due to a primitive continuity which had never been
broken, and that those who urged that such connections
were secondary were in the wrong. This suggestion was
contrary to fact, and it was my object to show that it was.
I did not contradict myself when I stated immediately
afterwards that the organism cannot be considered to consist
of independent life units, for I went on to show that the
cell-republic theory is also contrary to fact, and must there-
fore be condemned. If a contradiction exists, it exists in
nature, and after we have ascertained the facts the next
thing is to try to explain this seeming contradiction. Mr.
Sedgwick says that he does not think it possible to do so,
until we acquire some more understanding of the relative
functions of nuclei and protoplasm. Possibly he is right,
yet I think that an attempt may be made, and if the explana-
tion is after all not very satisfactory yet some service may
be done, for we may arrive at more distinct ideas about
fundamental points, and we must gain much by a careful

310 SCIENCE PROGRESS.

classification of the facts. Such a classification has yet to
be made. So long as a theory is dominant, as the cell-
republic theory was, exceptions and difficulties are glossed
over, or are explained away by a phrase. When I made a
vigorous onslaught on Mr. Sedgwick, I was afraid that he
wished to substitute King Stork for King Log and bring us
under the domination of a new theory of his own. His
reply to my strictures and his careful exposition of his own
standpoint are reassuring on this point, and if I exceeded the
limits of courtesy in my article, I did so under a misunder-
standing and express my regret for it. Mr. Sedgwick has
done a great service in breaking the bonds of the old theory.
Now the question is, having got our liberty, what are we
going to do with it ?

Firstly, I think, we have got to make up our minds as
to what we mean by a vital unit.

In the first part of this essay I stated that the cell is par
excellence the vital unit, by which I meant nothing more
than that it is the simplest form of material aggregate in
which individual life is possible. There would seem to be
no objection to such an application of the word unit. But
the term unit is a relative one, and its correlative is
multiple. If, therefore, we see that the developing embryoes
of many animals and likewise the tissues of the adult forms
are made up of structures which we must call cells, and if
we call the cell a vital unit, we are obliged to conclude that
the animals in question are composed of an aggregate of
vital units, which leads us directly to the doctrine of a cell-
republic. Thus at the outset we are confronted by the
great difficulty that what experience teaches us to deny
reason compels us to affirm.

There must be a flaw somewhere, either in the facts or
in the reasoning. There can hardly be any doubt about
the facts ; the flaw therefore must be in the reasoning, and
I do not doubt that it consists in our insistence on applying
the idea of a unit to biological facts. As Whewell would
have said, the idea is inappropriate. The term unit, as we
use it in Biology, conveys a double meaning. On the one
hand, it borrows part of its meaning from the idea of num-

THE PRESENT POSITION OF CELL-THEORY. 311

ber, and to this extent the term is used in an equivalent
sense to that in which it is used in Physics. But put side
by side such expressions as unit of mass or unit of time with
the expression unit of life, and a little reflection will suffice
to show that the sense is inappropriate. Nor is the case
made better if we compare the unit of life with the chemical
unit. The value of the latter consists essentially in this,
that it is a means of dealing numerically with chemical facts,
and experience shows that ideas of number are very
appropriate to chemical facts. With life the case is very
different. In the present state of our knowledge the con-
nection between life and number is of the slenderest kind,
and it is insufficient to justify our applying numerical ideas
to vital phenomena.

The other sense in which the term unit is used in
Biology is purely subjective. It stands to express our idea
of individuality, an idea which is founded on our own states
of consciousness. It is unnecessary for me to dilate upon
the controversies which have raged round this idea of in-
dividuality in its application to the animal kingdom. The
most acute reasoners are not agreed upon the precise
point where individuality ceases to belong to parts and
belongs to the whole even in some of the simpler colonial
organisms, and in such cases as the Siphonophora a satis-
factory solution of the problem appears to be hopeless.

But these cases are simple in comparison with that
which we are now discussing. If then we cannot agree
about the limit of individuality in colonial organisms, how
are we likely to agree about the same thing in the case of
organic structure in general ?

There is this to be said, however, that for us the test of
individuality should be a biological test, and the idea is there-
fore more appropriate to the question than the numerical idea
just spoken of. It was, no doubt, the recognition of its
propriety which lent such force to Schwann's argument,
" since it may be proved that some cells, which do not
differ from the rest in their mode of growth, are developed
independently, we must ascribe to all cells an independent
vitality ".

3i2 SCIENCE PROGRESS.

Hence, as it seems to me, whilst we can and ought to
get rid of the numerical idea expressed by the word unit, we
cannot get altogether rid of the idea of individuality, and
we must do our best to bring it into harmony with the facts.

Since there is an inseparable connection between the
idea of number and the word unit, we ought to get rid of
the expression " unit of life," and use some other term
which shall denote alike the simplest and the most com-
plex of living beings. The word organism I have aheady
objected to because of its double connotation — would it not
be better to make use of such a word as "biont," which is
as nearly as possible the equivalent of the German " Leben-
diges " ? Anything which leads or is capable of leading an
independent individual life is a biont. Thus a cell may be
a biont, as in the case of the protozoa, or it may be a con-
stituent part of a biont, as in the case of the metazoa. In
any case the cell is the simplest form of biont known, for if
we 2"o behind the cell we have structures which are not
capable of leading an independent individual life.

But a cell in the case of metazoa, or the nucleus and
other structures in the case of protozoa, and unicellular
plants are things which, whilst they participate in, and con-
tribute to life, and to that extent may be considered as living,
are not in themselves capable of independent individual
existence. They may be called metabionts.

The terminology suggested may not be perfect, but by
the use of it or of something equivalent we may shake our-
selves free of the false ideas which have clustered about
individual life units, and start with a new hope on an inquiry
into the nature and growth of bionts.

An essential part of our conception of a biont is the
union of two substances, cytoplasm and nuclein. It does
not matter, for present purposes, that we know nothing
exact about these two substances, and still less of the
manner in which they operate together to produce the
phenomena of life. It suffices that we know that there are
bionts whose structure is so simple that we can affirm no-
thing more of them than that they consist of cytoplasm and
nuclein, e.g., Bacteria, Yeast, Oscillaria, etc.

THE PRESENT POSITION OF CELL-THEORY. 313

Within the limits of the protozoa we study many kinds
of bionts which, whilst retaining great simplicity of structure,
have advanced far beyond the stage represented by these
simple forms.

The most important as well as the most striking
structural advance is the formation of a nucleus. The
nuclein which was, in the simplest bionts, distributed
through the protoplasm, is aggregated to form a compact
body, which from its structure and behaviour may be re-
garded as a metabiont, as also may the part from which it
was segregated, the cytoplasm. The steps which lead up
to the segregation of the nucleus are obscure, but there are
very good grounds for saying that the nucleus, when formed,
is connected, in some manner unknown to us, with the
transmission of the so-called historic qualities of the biont.
In any case it plays a leading part in reproduction, and the
steps from the condition of diffused nuclein to centralised
nuclein are suggested by the infusorian Holosticha scutelhim,
which ordinarily has no definite nucleus, but contains
numerous chromatin particles scattered throughout its sub-
stance. Previous to reproduction by division the scattered
particles are drawn together and unite to form a centralised
nucleus, which divides in a normal manner and breaks up
again into particles in the offspring.1

Besides the nucleus many other structural advances are
to be noted in protozoa and in unicellular plants ; some
must be regarded as metabionts, e.g., chlorophyll corpuscles
and chromatophores of various kinds, many kinds of granules,
etc. Other structures cannot be regarded as belonging to
the same category, e.g., cilia, contractile fibres, etc. We
may for the present purpose leave both cases out of con-
sideration, for it is the nucleus and the part it plays as an
essential constituent of the biont which most concerns us.

We have as yet very obscure notions about the co-opera-
tion of nucleus and cytoplasm in the production of vital
phenomena. But, putting aside the views of those who
postulate the existence of minute vital units, and speak of

1 Aug. Gruber, " Ueber vielkernige Protozoa," Biol. Centralblatt, iv., p.
170. See also the same author, Zeit.fiir Wiss. Zool., xli., p. 186.

22

314 SCIENCE PROGRESS.

an emanation of specialised biophors from the nucleus into
the cytoplasm, there is a general agreement that the co-
operation is of the nature of a complex exchange of
chemical material. If this be the case, the rate of exchange
must be the measure of vital activity, and it is clear that
the rate of exchange will be greatest in immediate proximity
to the nucleus and will become increasingly less the greater
the distance from the nucleus. At a certain distance, which
might be called the limit of nuclear influence, the rate of
exchange will be reduced to zero. We see that in the
protozoa the forms which have a single nucleus are small,
and we may say, in consequence of the foregoing- considera-
tions, that their size is determined by the limits of nuclear
influence. But many protozoa are multinuclear, and I
believe that there is no exception to the rule that protozoa
of relatively large size are also multinuclear. Such is
obviously the case in such forms as Radiolaria, Actino-
sphserium, Pelomyxa, the Myxomycetes and others. From
a consideration of all the facts of the case we may legiti-
mately infer that in any given biont growth beyond
certain limits is incompatible with a uninuclear condition,
and that further growth involves multiplication of the
nucleus, which may have as consequences: (i) discon-
tinuous growth, which in its simplest form is reproduction
by binary fission : (2) continuous growth, in which the
nucleus is multiplied so that all parts of the enlarged cyto-
plasm may receive an equal share of nuclear influence.
There are numerous cases in which, as I pointed out before,
the two conditions are combined. There is a ccenocytial r
stage of considerable duration, followed by reproduction
(or discontinuous growth).

The next phase is the formation of a biont of consider-
able size, in which very numerous nuclei are arranged in
definite manner in a continuous mass of protoplasm. Such
a condition is represented by the Cceloblastas, and also in the

1 When in my earlier essay I coined the word hypopolycytial I was
not aware that Professor Vines had applied the term ccenocytial to the
Cceloblastse. His term has the priority and is more euphonious, so I adopt
it instead of my own.

THE PRESENT POSITION OF CELL-THEORY. 315

growing tissues of many animals and plants, as for instance
in the embryoes of many Arthropods, in the endosperm of
Phanerogams, etc. The condition may be permanent, as
in the case of the Cceloblastae, or non-permanent, as in the
other cases. But in both instances there is a difference
from the ccenocytial condition observed in Protozoa, namely,
that the multiplication of the nucleus does not lead to re-
production in the form of the splitting up of the biont into
as many new bionts as there are nuclei.

In a ccenocytial biont of appreciable size the relations
of the various parts to external conditions will tend to be-
come different, and differences of chemical constitution will
be set up in the different regions exposed to different con-
ditions. We can see that this is the case in Botrydium, in
which root and shoot are plainly marked off from one
another, and better still in Caulerpa, in Codium, and in
many of the Moulds. Differences in chemical constitution
thus induced will mean difference in exchange between
nucleus and cytoplasm, and we may infer that, in accordance
with these differences, the cytoplasm within the limit of
influence of any one nucleus will in time assume a con-
stitution so different from that of the adjacent cytoplasm as
to become sharply marked off from it. It will then acquire
its own surface tension — the first step towards a cell wall—
and will be a separate corpuscle containing a nucleus, in
fact a cell. Such a cell however has not come into being as
an individual unit joined to its like, either phylogenetically
or ontogenetically, but it has from the first formed a part
of an organic whole, of which it is nothing more than a
specialised component part.

One looks naturally for evidence of this mode of forma-
tion of cellular structure in developing Metazoa. The best
evidence is to be found, I think, in the segmentation and
formation of the layers in many Ccelenterata. In some
Ccelenterata — for example, in Renilla — the nucleus divides
without accompanying division of the cytoplasm until eight
or sixteen nuclei are present, and then the cytoplasm
divides and eight or sixteen cells are formed. But of more
importance than this is the formation of the layers. From

316 SCIENCE PROGRESS.

the considerations stated above we should expect that the
changes in chemical composition of the cytoplasm and the
correlated changes in the nucleus, in other words the dif-
ferentiation, would first become manifest in the peripheral
parts of the growing ccenocyte, and that we should have a
stage in which there was a cellular external layer and a
ccenocytial internal mass. We find that in fact in the
embryoes of many Ccelenterates the outer layer is divided
up early into sharply defined cells at an early period, whilst
the central cells retain the character of a ccenocytium ; at
most the cell outlines of the internal mass are confused and
indistinct.

We see also that in the growing tissues of the embryoes
of higher animals the embryonic tissue is not cellular but is
a ccenocytium, for example, the mesoblast of Avian and
Selachian embryoes and of the Rabbit. It is only at a later
stage when different relations to other parts of the body
have been acquired and new exchanges of material are
forced upon the growing mass, that the continuous mass of
cytoplasm is split up into corpuscles, each of which, in my
view, corresponds to the limit of influence of a nucleus.

On the other hand we have the undoubted fact that in
many organisms there is no ccenocytial phase in develop-
ment, but the cytoplasm surrounding the nuclei as they are
successively formed is immediately marked off into definite
corpuscles, so that the whole process of development
suggests the formation of an aggregate of bionts derived by
division from a single parental biont. An explanation of
this fact presents many difficulties, and I have not now
the space to discuss these difficulties and to show that,
obscure as the subject still is, there is ground for supposing
that the difficulties are chiefly due to the prepossession
which exists in most minds in favour of the independent
life unit theory. I hinted in my previous paper (loc. ciL, p.
171) that the discrete condition of the blastomeres of so
many embryoes may be connected with the fact that they
are, from the very outset, specialised. This means that as
the nucleus is in some way associated with the transmission
of historic qualities, these qualities may be located in special

THE PRESENT POSITION OF CELL-THEORY. 317

parts of the nucleus, and on division, some of the daughter
nuclei may possess one set, others may possess another set
of " qualities ". By " qualities " I conceive that we mean
different chemical constitutions, and it would follow that the
daughter nuclei, being of diverse chemical constitutions,
would react in diverse manners on the adjacent protoplasm
and would each cause the delimitation of a territory of
cytoplasm within the limits of its own sphere of influence ;
in other words, cell bodies would be formed round nuclei of
different chemical constitutions.

There is, however, yet another consideration to be taken
into account. As Hertwig has shown, the cytoplasm in
many ova is not homogeneous but is obviously separable
into tracts of unquestionably different chemical constitution.
This is conspicuously evident in the ova of Amphibia. As
the nucleus divides, its products come into relation with
different kinds of cytoplasm and the exchanges between
nucleus and cytoplasm will be different in different places
within the limits of the egg. Arguing on the same prin-
ciples as before, we may attribute the successive formation
of discrete blastomeres to this factor as much as to the
separation in the course of division of different qualities
contained in the egg nucleus, and according as one leans
towards an epigenetic or an evolutionary theory of develop-
ment so will one be disposed to lay more stress on the
one factor or the other. There is this much to be said,
that the most remarkable cell-lineages (which are only
traceable when the blastomeres are discrete) have been
observed in ova which contain a considerable proportion of
yolk, which is not evenly distributed throughout the egg,
and it is suggestive that segmentation in all cases leads to
the segregation of corpuscles richer in yolk from corpuscles
poorer in yolk — in fact to the segregation of materials of
diverse chemical constitution.

Tempting as it is to pursue this subject further, I must
not attempt to do it now. But as I have claimed that the
views which I have tentatively put forward are agreeable
to the facts which we are in possession of, I may well give
a short summary of the facts which I have relied upon.

318 SCIENCE PROGRESS.

( i ) The co-existence of two substances at least, nuclein
and cytoplasm, is requisite for life. (This is an inference,
strictly speaking, and not a fact ; but I think that it may be
considered a legitimate inference from what we know of the
structure of the lowest bionts, and from the experiments of
Nussbaum, Gruber, Verworn and others.)

(2) The existence of bionts, such as Bacteria, in which
we are unable to distinguish more than these two sub-
stances. (This is a fact, which lends material support to
the above inference.)

(3) The existence of bionts in which nuclein and cyto-
plasm are not indefinitely intermingled, but the former is
segregated in the form of particles scattered through the
protoplasm, e.g., Trachelocerca phcenicopterus and Chcenia
teres. (We gather from this fact that the two chemical
substances tend to become separated from one another.)

(4) The temporary aggregation of nuclein particles to
form a centralised nucleus for the purpose of the repro-
ductive act, e.g., Holosticha scutellwm. (We infer from this
that there is some connection, at present hidden from us,
between the nucleus and the reproductive act.)

(5) The existence of many bionts in which the nuclein
is concentrated to form a nucleus. (We infer that this
is a grade of permanent differentiation arising out of
the previous temporary grade.)

(6) The existence of many nuclei in all bionts which,
whilst still undivided as regards their cytoplasm, attain to a
certain size. (From this we infer that the " limit of nuclear
influence " cannot extend through a large mass of cyto-
plasm.)

(7) The origin of "cellular" tissues from a ccenocytial
mass, e.g., the endosperm of Phanerogams; the neural
crest of certain Vertebrate embryoes ; the embryoes of
Arthropods; the mesoblast of many Vertebrates, etc. (From
this we infer that the cells composing many tissues of higher
animals are not to be regarded as bionts, but are secondarily
derived during the growth and extension of the parts of a
single biont.)

This re'sume suffices I think to show that this at least

THE PRESENT POSITION OF CELL-THEORY. 319

may be claimed for the views which I have put forward.
They are founded strictly on the facts, and they do not
depend on the assumption of any kind of hypothetical units
of which the nature and even the very existence is entirely
beyond our ken.

Since I have not been able to develop my views, I
cannot but expect that they will be subject to considerable
modification and even to entire overthrow. They form at
least an attempt to classify and colligate the various pheno-
mena which seem to be germane to the subject, and I have
collected and compared a much larger body of facts than I
am here able to refer to, without finding any which are
contradictory to my ideas. That my ideas are somewhat
indistinct need not, at present, be urged as an objection, for
indistinctness is not necessarily a sign of falsity. The cell-
republic theory was not wanting in distinctness, but
it was inappropriate to the facts. I only claim that my
ideas are appropriate, and I shall hope to give them more
distinctness on a future occasion.

In the meantime I leave out of consideration a large
question, concerning which I think it scarcely possible to
give a satisfactory account, in this standing in opposition to
Mr. Sedgwick, who thinks that which I have attempted to
be impossible, but offers a solution of that which I think
scarcely possible.

The question is, how are we to account for that pheno-
menon which I have described as a progress from the state
of an independent corpuscle, through a state of many coherent
or continuous or conjunct interdependent corpuscles, back
again to the state of a single independent corpuscle ?

Mr. Sedgwick's solution is this : that the unicellular
form is assumed by metazoa in order that conjugation may
be possible. The single independent corpuscle which re-
curs in the cycle is the sexual cell, and the essential feature
of sexual reproduction is the conjugation of reproductive
cells. The unicellular phase is only assumed in sexual, not
in asexual reproduction, and this is to be explained by the
consideration that conjugation is as necessary in metazoan
life as in protozoan life, but that conjugation between the

320 SCIENCE PROGRESS.

ordinary forms of metazoa is impossible for mechanical
reasons, and therefore special individuals of a form simple
enough to admit of conjugation are produced. These
special individuals are the ovum and spermatozoon.

The explanation is extremely ingenious and there is
nothing unreasonable in it, but one cannot say that it is
altogether acceptable at first sight. It would have been
more satisfying if Mr. Sedgwick had marshalled some of
the facts relative to the sexual reproduction of some of the
lowest multicellular organisms and had shown their rela-
tion to his suggestion. A difficulty which at once occurs
to me is that in many plants asexual reproduction is
effected through the agency of a single cell. In fact,
before one can accept any solution of the question one
requires a very extensive and careful survey of all the facts
known about the reproduction of the lower plants. They
afford examples of every conceivable grade of the reproduc-
tive processes, and, once one begins to look into the subject,
hints as to the parting of the ways of sexual and asexual
reproduction occur to one at every step. The pity is that
the mere zoologist, who does not find such a fruitful field in
his own territory, is obliged to disinter the facts from the
load which the peculiarities of botanical terminology have
heaped upon them.

It is quite possible, however, that such a survey would
afford strong support to Mr. Sedgwick's opinions, and if it
should do so they would in no way be inconsistent with
the ideas which I have put forward, but would rather sup-
port them.

A word in conclusion for those who will reproach me
for having attempted to frame a chemico-physical theory
of organic growth, and for having used such phrases as
" complex chemical constitution," " exchange of chemical
material," etc., without assigning any distinct meaning
to them. I admit that our knowledge on the subject
is rather inadequate, and that I have used obscure phrases
to express relations which are in themselves obscure. If
one attempts to lift the veil of obscurity one must inevitably

THE PRESENT POSITION OF CELL-THEORY. 321

call hypothesis to aid, and it has been my object to avoid
the use of hypothesis where I could do without it. It is,
however, legitimate to frame an argument which, while it
agrees with the lessons of experience, is ultimately based
upon hypothetical considerations, provided always that those
considerations are consistent with the accepted teaching of
the sciences whose aid is invoked.

Any attempt whatever to find an explanation of vital
phenomena ends in an appeal to chemistry and physics.
Knowing as we do that the elements of which organic
bodies are composed are not different from those which
occur in the inorganic world, we cannot refuse to acknow-
ledge that vital processes are in the end chemico-physical
processes, and this much is conceded by every author of a
theory of vital units. The difficulty which they have to
face is the same as that which I have to face, and is not one
whit the less because it is compressed into the limits of
a biophor, whereas I would allow it the limits of a cell.
Can we frame any distinct ideas of these chemico-physical
processes ? Not very distinct ideas, perhaps, yet we can
supplement the lack of positive evidence by analogies and
illustrations involving the same ideas as those which are
current in the physical world.

It was Professor W. K. Clifford, I think, who first drew
a graphic picture of the molecular forces which are at work
in any chemical compound, by describing the atoms as
linked to one another and dancing a sort of merry-go-round
within circumscribed limits. We may carry on the illustra-
tion, which, fanciful though it may seem, is supported by
physical and mathematical considerations. A biont is a
great organised war dance, performed by a whole army
corps. The individuals composing each company are the
atoms, they are linked to one another by companies and
each company dances its own figure. Every company is a
molecule, and every company dance is but a part of a larger
dance, in which the companies act in relation to one another
as the individuals act in the company dance. The larger
dances are regimental dances and every regiment is a
micella. The regimental dances are but parts of still larger

322 SCIENCE PROGRESS.

brigade dances, and the brigade dances are but part of the
great dance of the whole army corps, which, taken as a
whole, is the biont. The illustration is not quite exact, for
each company must not be considered as consisting of like
individuals, but of many individuals of all arms, some like
and some unlike, linked in such various ways that no two
companies are the same, partly because of the proportions of
different kinds of individuals composing them, partly because
of the way in which those individuals are linked together.
Nor must we imagine that individuals are permanently
attached to companies, nor yet companies to regiments, but
that in the course of the dance individuals are passed from
company to company, and companies from regiment to
regiment, each conforming temporarily to the particular
figure of that part of the dance to which he or it for the
time belongs. Further than this the individuals engaged
in the whole dance are never lone the same : there are
bystanders who for a time do not participate in the dance
but are caught up one by one, whirled through the figures,
passed from company to company, from regiment to regi-
ment and brigade to brigade, and are eventually passed out
of the dance again, after having participated in some or all
of the figures as the case may be. Every individual in the
dance is at some time passed out of the dance, becomes
a bystander, and may again be caught up and whirled along
in the dance once more.

The illustration is farfciful, if you please, but it is of the
same kind as illustrations used to depict the play of mole-
cular forces in the inorganic world. It serves a purpose in
that it gives the imagination something to work upon, and
it enables one to conceive of the immense complexity which
is possible in a chemico-physical process. The army dance
which I describe is capable of any number of combinations,
a number amply sufficient to satisfy the needs of those who
insist so strongly on the marvellous complexity of life.
Let anybody imagine an army to be composed of four
brigades, each brigade of four regiments, each regiment of
ten companies, and each company to contain 100 indi-
viduals of the eight kinds, carbon, oxygen, hydrogen,

THE PRESENT POSITION OF CELL-THEORY. 323

nitrogen, sulphur, phosphorus, potassium and iron, in
varying proportions, and let him work out the possible
combinations. I think he will be satisfied with the com-
plexity.

What then of heredity and of the capacity which I have
mentioned for acquiring historic qualities ?

Believing as I do that the vital processes must in the
end be attributed to a particular mode of molecular motion,
I believe that it is the form of movement which is trans-
mitted. Returning to my illustration I would say that it is
the figure of the whole dance which makes up the species,
and that it is the figure — the mode of motion — which is
inherited, clearly not the individuals engaged in the dance,
except in a very small degree, for they are constantly
coming into the dance anew and as constantly being passed
out of it. Under certain circumstances there may be an
excess of one or more kinds of new individuals pressing into
one part of the dance which will affect the figure of the
company dance which they crowd into, and this will affect
regimental figures and ultimately, in decreasing degrees,
the whole army figure. In this way we may picture to
ourselves the action of external influences in bringring about
variation. But I have given rein enough to my imagina-
tion. The picture was introduced partly to show that
beneath my obscure phrases there was some distinctness of
ideas, partly to emphasise the immense complexity of
Nature and to show that even atoms and molecules may be
conceived to be so combined together that, in Goethe's
words, " sie bewirken so eine unendliche Production aut
alle Weise und nach alien Seiten ".

Gilbert C. Bourne.

THE HEREDITARY TRANSMISSION OF
MICRO-ORGANISMS.

IT is well known that in the construction of many of the
theories of heredity the doctrine of the transmission of
acquired characters has obtained considerable prominence.
The hypothesis of Lamarck rendered it necessary to assume
that structural characters which had arisen from the use or
disuse of organs, became an integral part of the individual
and reappeared in the descendants, and although the appli-
cation of this idea became greatly restricted when the
principle of natural selection was established, it is only
within the last few years that the transmission of acquired
characters has been considered as unproven, and the in-
stances put forward in support of this view to be capable
of a different explanation. It may be admitted that mutila-
tions and permanent injuries can be included among acquired
characters, and the structural and functional modifications of
the individual which occur in disease may persist, and
therefore also be considered as definite morphological or
physiological changes. Mutilations apparently do not pass
from parent to offspring, and this has been especially pointed
out by Weismann and his followers, since, if heredity is
capable of explanation on the hypothesis of the continuity
of germ-plasm contained in definite reproductive cells, any
change in the structure or modes of activity of the essential
body or somatic cells would not be transmitted. An iden-
tical line of argument also negatives the belief that diseases
can be inherited, and this view was maintained by Weismann
in his well-known criticism on the transmission of experi-
mental epilepsy ; the symptoms in this hereditary disease he
considered might be due to some unknown microbe which
found its nutritive medium in the nervous tissues and
was transmitted in the reproductive cells. The question
whether micro-organisms can actually pass from parent to off-
spring is one which has been carefully investigated, whereas

TRANSMISSION OF MICRO-ORGANISMS. 325

the proof that actual morphological changes, such as modi-
fications of histological or molecular structure, can be trans-
mitted has not yet been given. It is conceivable that
predispositions may be inherited, and these must result
from alterations in the germ-plasm, or a direct infection of
the germ or embryo might cause the transference of a dis-
ease from one generation to another, a phenomenon which
simply depends upon a particular mode of conveyance of a
parasite.1

In many diseases, and particularly those which are directly
caused by micro-organisms, it is a matter of interest to note
the wide differences which exist between the conveyance
of hereditary characters, and of a specific disease. Armauer
Hansen (1) has made this perfectly clear in considering the
etiology of leprosy. He has pointed out that true heredi-
tary characters are usually limited to one sex, frequently
appear at a particular age, and the phenomenon of atavism
is not rare ; but in the conveyance of such a disease as
tuberculosis or leprosy, none of these conditions are ful-
filled. It is a logical deduction from the consideration of
these differences that every specific disease which is trans-
mitted cannot be regarded as hereditary, but as an instance
of the direct bacterial infection of the germ-cells or embryo.
Most writers on cancer and malignant growths have dis-
cussed the hereditary transmission of this disease, and if it
is allowed that a disposition to cancer may be derived by
inheritance, then this condition would depend upon some
peculiarity inherent in the nucleus of the germ-cells ; but
if, on the other hand, malignant disease is caused by a
parasite belonging, as some investigators have sought to
prove, to the group of protozoa or protophyta, then the
transmission of the actual disease will depend upon the
passage of a micro-organism which invades the germ or its

1 " Pour les maladies, vraiement constitutionnelles, c'est la substance
hereditaire elle-meme qui est viceuse; pour les maladies infectieuses, levice
n'est pas dans la substance elle-meme, mais a cote d'elle, et les produits
sexuels servent seulement de vehicule a un parasite capable d'engendrer
plus tard une maladie generate. " Y. Delage, La Structure du Protoplasma
et les Theories sur F Heredite. Paris, 1895.

326 SCIENCE PROGRESS.

product, and the whole phenomenon ceases to be one of
heredity, for the hereditary transmission of micro-organisms
is simply a particular instance of bacterial infection. The
inheritance of actual specific disease must therefore always
be considered as a problem absolutely distinct from that
of heredity and incapable of explanation by any hypothesis
of heredity.

Micro-organisms which reach an individual either by
inheritance or other modes of conveyance may undoubtedly
exhibit a period of latent life extending over many years ;
but when this condition is succeeded by an active life, to
establish the proof of an hereditary transmission is ex-
ceedingly difficult or even impossible (11). The early
researches into problems of this nature were necessarily
made with the help of statistical and clinical methods ; but
it is the application of experimental methods, which could
only be pursued with success as the study of bacteriology
developed, that has finally succeeded in removing the subject
of the hereditary transmission of specific diseases from the
hazy region of speculation. The attitude assumed by
Baumgarten and his followers on this question is well
known. In the case of tuberculosis it is maintained
that individuals are rarely infected with tubercle bacilli
after birth, but that the disease in the majority of cases is
due to a parasitic infection of the egg-cell or embryo. It
is even urged that the bacilli may remain latent in one
individual, and only enter upon a phase of activity in the
offspring, a view which, if correct, would accord with the
opinion of many clinical observers. While destroying the
opinion so commonly held that an "inherited tubercular
predisposition " exists, Baumgarten's theory of hereditary
parasitism makes a still greater demand on the imagina-
tion ; but that the views of this distinguished pathologist
have acted as a stimulus to renewed experimental work on
the transmission of micro-organisms is beyond doubt.
Recent papers by O. Lubarsch (2) of Rostock and J.
Csokor (3) of Vienna give an admirable exposition of the
present position of our knowledge on this subject of the
transference of bacteria from parent to offspring in man and

TRANSMISSION OF MICRO-ORGANISMS. 327

the lower animals, and the evidence that bacteria may in
this manner gain access to the organism is incontestable.

In inherited specific diseases it is possible to distinguish
two forms of infection : first, by a direct bacterial invasion of
the essential reproductive cells ; secondly, the egg-cell or
the embryo may receive micro-organisms from the female,
in which case the blood stream is the channel for conveyance,
and the whole phenomenon is then one of metastasis com-
parable in every respect to what obtains when bacteria
multiply at a definite area of the body, and thence become
distributed by the blood and lymph in distant parts of the
organism. Bacterial infection may therefore be either
germinative or placental, and in mammals the latter
form of transmission is not infrequently observed. The
specific bacteria of anthrax, typhoid fever (6), pneumonia
and tuberculosis (7) have been isolated from the human foetus,
cultivated, and successfully inoculated upon animals, so
that the chain of evidence is complete. The pyogenic
cocci such as streptococcus pyogenes (24) and staphylococcus
pyogenes aureus have also been demonstrated in foetal
tissues by Fraenkel and Kiderlen, and Auche has shown
that in small-pox the placenta may be penetrated by these
micro-organisms. In the lower animals not only may the
bacteria already mentioned be transmitted, but also those of
cholera, glanders and chicken cholera.

In many animals the egg-cell is the largest unit of the
organism, and would be capable of containing numberless
bacteria ; that such an infection does occur was first estab-
lished by the classical observations of Pasteur (4), which
have been confirmed by all subsequent investigators. In
pebrine, a disease of silk-worms, definite sporocyst forms
(microsporidia or Cornalia's corpuscles) are transmitted from
the imago in the egg-cell, and the larva is directly infected
in this manner. Blochmann (5) has also described a similar
mode of conveyance of bacteria in the ova of Blatta
orientalis. In a single instance a tubercle bacillus has
been seen in the mammalian ovum. The sperm-mother-
cells may also be invaded by micro-organisms, but this is
rare, and no example of an infected male reproductive cell

328 SCIENCE PROGRESS.

exists. That this condition will ever be demonstrated is
improbable, since bacteria contrast with parasitic protozoa
in infecting the cell and sparing the cell-nucleus, and the
essential agent in the process of fertilisation is the nucleus
or head of the sperm-cell.

Various observers have attempted a solution of this
question of germinative infection by the employment of
two different methods. The first of these is that pursued
by Mafifucci, who directly infected the fertilised eggs of the
fowl, and in the second not only were the genital glands
and the products of these examined for micro-organisms,
but pieces of them were taken from animals suffering with
specific diseases and used as material for inoculation.

Even if it is assumed that an ovum actually is a site in
which bacilli such as those of tuberculosis exist, it may be
objected either that the microbe is dead, or that such a cell
is incapable of development. This is the attitude taken by
Virchow, who absolutely denies the existence of congenital
tuberculosis. Maffucci's experiments, however, contra-
dict this opinion, for this observer has shown that the
bacilli of avian tuberculosis develop in an infected embryo,
and the chicken succumbs to tuberculosis in twenty days
to four and a half months after hatching. If, however,
instead of infecting the embryo, bacteria such as those of
chicken cholera, or anthrax, or Friedlander's pneumococcus
are introduced in the extra-embryonic area, then these
organisms may actually enter the embryo through the
allantois but do not increase in number provided the
embryo remains alive. The pathogenic micro-organisms
may therefore be destroyed or attenuated by actively pro-
liferating embryonic tissue cells, or they may become capable
of development at a later period of life, in other words,
remain latent. Although these experiments were devised
to establish the view that a genuine germinative infection
may occur, they obviously do nothing of the kind, and it is
to the researches of Gartner that we owe an absolute
demonstration that ova may contain pathogenic germs.
Gartner among: other animals inoculated canaries with mam-
malian tubercle bacilli. After a few weeks he removed

TRANSMISSION OF MICRO-ORGANISMS. 329

nine eggs, washed these in dilute corrosive sublimate,
dried them in wool and introduced the contents of each eo-or
into the peritoneal cavity of guinea-pigs. In two cases
tuberculosis was set up, the animals dying one and a half
months and two and a half months after infection. These
experiments, which are absolutely free from objection,
conclusively prove that the egg-cell may contain virulent
bacteria, and it is easily conceivable that such eggs may
develop and the transmission of the parasite take place by
direct germinative infection, especially since Maffucci's
work shows that such infected eggs are capable of develop-
ment.

Jani, Westermayer, Spano, Walther, Gartner, and quite
recently Jakh, have microscopically investigated the bac-
terial contents of the reproductive glands, and also inoculated
animals with fragments of these organs. With the exception
of Gartner's researches these experiments have not added
greatly to our knowledge of the hereditary transmission of
bacteria. All the experiments of Westermayer were nega-
tive. In fourteen cases of well-marked General tuberculosis
no tubercle bacilli could be recognised, and inoculation
experiments were failures. The experiments of Jakh (10)
were more fortunate. Five inoculations with pieces of the
male reproductive gland and its product, taken from in-
dividuals dead of tuberculosis, gave three positive results.
If the gland alone was used, the experiments were always
negative, and of three inoculations with pieces of the egg-
forming gland one was successful. It may be admitted that
these experiments do not really throw much light on the
subject of germinative infection, but Gartner's researches
are of much greater value. He experimented upon mice,
guinea-pigs, rabbits, and canaries, these birds being sus-
ceptible to mammalian tubercle bacilli. Having inoculated
these animals with bacillus tuberculosis, a careful examination
was made of the offspring of such tubercular parents. This
method might naturally be expected to give a conclusive
answer to the question of hereditary infection, and the
following information has been gained from these researches :
1. The sperm rarely contains tubercle bacilli — five in

23

330 SCIENCE PROGRESS.

thirty-two cases. Even if micro-organisms exist they are
incapable of infecting the egg. In twenty-two (rabbits)
and twenty-one cases (guinea-pigs) where the male repro-
ductive gland was the seat of an acute tubercular process,
the offspring were never infected. 2. Neither does the
male infect the female by way of the sperm. 3. Infection
takes place frequently from the female to the foetus, and in
an overwhelming majority of cases by way of the placenta.

A few considerations may make the importance of Gart-
ner's work more evident. If bacilli exist, as they occasionally
do, in the product of the male gland it is probable that this
material, like other parts of the body, contains bacteria only
a few days before death, for we know that quite an abnormal
number of micro-organisms may invade the whole organism
during the last days of life. Tubercle bacilli are immotile
and therefore will not easily reach the oviduct or egg, a
matter of some importance, since it has been shown that in
most cases the ovum is fertilised either high up in the
oviduct or even at the time of liberation from the Graafian
follicle. Stroganoff (12) has also pointed out that the
uterine area is sterile, and the secretion of this is bacteri-
cidal, in which it resembles sputum (13) or the mucus of the
nasal tract which is almost free from germs (14). Lastly, it is
well known that a single male morphological unit is sufficient
for fertilisation, and if we assume with Gartner that 100
virulent tubercle bacilli are mixed with sperm-cells, the
ratio of bacteria to these would be about 1 : 22,500,000 ; it
is hardly conceivable on the doctrine of probabilities that a
bacillus would gain access to the egg. It may therefore be
considered, both on experimental and theoretical grounds,
that a germinative infection of the ovum never occurs by
the conveyance of micro-organisms in the male reproductive
cells.

The difficulties which exist in proving that the in-
heritance of a specific disease may occur through an in-
fection of the ovum are fortunately not so great in those cases
where the passage of micro-organisms takes place solely
from the female to the fcetus by way of the placenta. It is
established that specific micro-organisms can pass by this

TRANSMISSION OF MICRO-ORGANISMS. 331

route. It is not even necessary to assume that there is any
lesion whatever in the placenta or that the epithelium of
the foetal villi is destroyed. An experiment by Zuntz
shows clearly that particulate material will easily pass into
the amniotic fluid from the maternal portion of the
placenta, for if indigo-carmine is injected into the veins
of the female the dye passes into the amnion leaving the
foetus free, and in this very manner anthrax bacilli may
pass, and from the amnion gain access to the mouth of
the foetus, enter the gut and set up disease by a
primary infection of the wall of the intestine (25). An intra-
uterine infection, therefore, can occur without lesion of the
placenta, though in the majority of cases this structure is
primarily infected, and then the foetus, or else haemorrhages
of the placenta permit the passage of micro-organisms.
However the undoubted fact that micro-organisms can

o

penetrate the healthy skin by way of the hair follicles — and
the same is possibly true for the epithelium of the urinary
tract — must not be forgotten in considering the passage of
bacteria across the placenta. This structure may be nor-
mal and even then allow the transit of bacteria. Birch-
Hirschfeld (15) from researches on the structure of the
human placenta as well as that of mice, rabbits and goats
considers that the bacilli of anthrax at any rate can
traverse the uninjured chorionic epithelium. Moreover in
the human placenta and in rabbits numerous processes of
the chorion traverse the placental sinuses, and these pro-
cesses are normally destitute of epithelium. It was noticed
by Max Wolff (16) that anthrax bacilli easily pass if the
placenta was crushed or torn, and micro-organisms which
exert a necrotic influence on tissues, such as the pyogenic
cocci, appear first to destroy the epithelium of the
chorionic villi, and then pass through into the foetal
blood. In this fluid micro-organisms reach the liver, and
it is this organ which, as a rule, is primarily affected, and
then the glands in the lymphatics leading from the organ
become implicated. The location, therefore, of tubercles
in foetal tuberculosis is characteristic, and all observers
insist upon this feature in determining whether tubercular

332 SCIENCE PROGRESS.

deposits are of intra- or extra-uterine origin in early cases
of the disease. As a matter of interest it may be
mentioned that quite recently Bar and Renon have de-
monstrated tubercle bacilli in the blood of the umbilical
vein (7). The method used by these observers, that of
inoculating guinea-pigs with the suspected blood, and in
this manner establishing tuberculosis, is not so convincing
as the actual demonstration of bacteria in fcetal tissues.
Wassermann (17) in a recent paper especially insists on
this point, and discards all evidence of inherited disease
which rests simply upon inoculation experiments. He
describes a case of early tuberculosis which ended fatally
when the child was ten weeks old, where the disease was
acquired, not from the parents who were healthy, but by
direct infection from a tubercular relation, and believes that
such cases as these are not infrequently cited as instances
of congenital disease. In his opinion hereditary trans-
mission of bacteria does occur, but it is exceedingly rare
in comparison with the frequency of extra-uterine infection.
Bernheim (18) considers that the offspring rarely, if ever,
become tubercular if separated from tubercular parents,
with the exception of those cases where the placenta is
infected. The case reported by Ivan Honl (19) of a child
fifteen days old that on autopsy showed tubercular nodules
in the liver, spleen, and lungs, and numerous bacilli,
must be classed as a definite case of transmission which with
many others lends no support to Eberth's statement that
individuals do not inherit tuberculosis but acquire it (23).

A recent case of congenital typhoid fever is related by
Freund and Levy (20), and instances of transmitted hemor-
rhagic infection have been recorded by Neumann (21) and
by Dungern (22). The numerous examples which the
journals of veterinary science contain, especially the work
of Bang, Kockel, and Lungwitz, also afford conclusive evi-
dence of the transmission of pathogenic micro-organisms,
though there is a consensus of opinion that the placental
is far more frequent than the germinative infection. The
share borne by the male in this transmission may be dis-
regarded, as no bacteriological evidence exists to support

TRANSMISSION OF MICRO-ORGANISMS. 333

this view. Finally, the frequency of hereditary transmission
of pathogenic germs is exceedingly small compared to other
modes of infection.

BIBLIOGRAPHY.

(1) HANSEN and LOOFT. Leprosy in its Clinical and Pathological

Aspects, 1895.

(2) Lubarsch. Ergebnisse der allgemeinen Atiologie der Mens-

chen-und Tierkrankheiten, by Lubarsch and Ostertag, p. 427,
1896. References to the transmission of infectious diseases
to descendants will be found in this and the following paper.
Some additional and later references are given in the course
of this article.

(3) Csokor. Ibid., p. 456.

(4) Pasteur. Etudes sur les maladies des vers a soie, t. i.,'p. 70,

1870.

(5) BLOCHMANN. Quoted by L. Pfeiffer in Die Protozoen als

Krankheitserreger ; 1 89 1 .

(6) Janiscewski. Munch, med. Wochenschrift, 1893.

(7) Bar and Renon. Comptes Rendus, No. 23, 1895.
Londe. Comptes Rendus, No. 25, 1895.

Nocard. Un nouveau cas de tuberculose congenitale. Rev.
de Tuberculose, No. 3, 1896.

(8) MAFFUCCI. Centralbl. f. Bakt. u. Parasitenkunde, Bd. v., No.

7 ; and Centralbl. f. allg. Pathologie, No. 1, 1894.

(9) Gartner. Zeitschrift f. Hygiene, Bd. xiii.

(10) Jakh. Virchow's Archiv, Bd. cxlii., 1895.

(11) Washbourne and others in the discussion on latent micro-

organisms at the Medico-Chirurgical Society, London.
Lancet, November, 1895.

(12) Stroganoff. Centralbl./. Gyndkologie, No. 38, 1895.

(13) Sanarelli. Centralbl. f Bakt., Bd. x., 1892.

(14) Hewlett. Lancet, June, 1895.

(15) Birch-Hirschfeld. Zieglers Beitr. z. path. Anat.u. allg.

Path., Bd. ix., 1891.

(16) Wolff. M. Intemat. Beitr. z. wissensch. Med. Festschr. f.

R. Virchow, Bd. iii., 1891.

(17) Wassermann. Zeitschrift f. Hygiene, Bd. xvii., 1894.
KOSSEL, H. Zeitschrift f. Hygiene, Bd. xxi., 1895.

(18) Bernheim. Erblichkeit und Ansteckung der Tuberculose.

Mitteilungen aus dem xi. internat. med. Kongresse in Rom,
1894. Reference in Centralbl. f Bakt., No. 17, 1894.

334 SCIENCE PROGRESS.

(19) Honl. Uber kongenitale Tuberkulose. Reference in Centralbl.

f. Bakt., Bd. xviii., 1895.

(20) FREUNDand Levy. Berliner klin. Wochenschrift,No. 25, 1895.

(21) Neumann. Archiv f. Kinderheilkunde, Bd. xiii.

(22) DUNGERN. Centralbl. f. Bakt., Bd. xiv., 1893.

(23) Eberth. Die Tuberculose, ihre Verbreitung und Verhiitung,

1 891.

(24) RlCKER. Centralbl. f. allg. Path. v. path. Anat., Jan., 1895.

(25) KOCKEL and LUNGWITZ. Beitr. z. path. Anat. v. allgem.

Path., Bd. xxi.

George A. Buckmaster.

Science progress*

No. 29. July, 1896. Vol. V.

PREHISTORIC MAN IN THE EASTERN
MEDITERRANEAN.

THE purpose of these notes is to summarise the results
of recent research among the prehistoric peoples and
civilisation of the Eastern Mediterranean ; especially in so
far as these prepare the environment for the first great
civilisation of Europe, namely, that of Greece, and fill the
chronological gap, and explain such communication as
existed, between this and the equally " historic " but far
earlier civilisations of the Euphrates and Nile Valleys.

A strictly " Historic " Age on the shores of the ^gean
Sea, or in fact in the Eastern Mediterranean at all, cannot
be said to begin before the seventh or at earliest the end of
the eighth century B.C. ; and everything before this point
would certainly have been classed as " Prehistoric," but for
the fact that, until quite lately, the preceding centuries have
been interpreted wholly in the light of a voluminous Greek
tradition, which is still accepted in many quarters as
fundamentally historical ; though now with wide reserva-
tions everywhere. Consequently prehistoric archaeology
and ethnology have here come into existence as accessory
and supplementary studies, and the data of the literary
tradition have been used, as was inevitable, as a working
hypothesis ; which, it is only fair to say, has served its purpose
fully as well as there was every reason to expect. Con-
sequently again, any account of the more recent and more

24

336 SCIENCE PROGRESS.

strictly anthropological work in this field must stand, if it is
to be intelligible, in close relation with the data and
assumptions, which have so mainly determined its course.

ANCIENT TRADITIONS AND MODERN INTERPRETATIONS.

i. The data upon which Greeks of the sixth and early
fifth centuries relied for the reconstruction of their own
history consisted wholly of traditional anecdotes, appended
to traditional genealogies, or grouped, in more or less organic
connection, round equally traditional events, such as an
invasion of the Troad, or an exploration of the Euxine, or
the adventures of a typical navigator like Odysseus. Many
of the lays in which these anecdotes were preserved can be
traced with some probability to their places of origin, which
range from Cyprus to the islands off the west coast of
Greece, and from Thessaly and the Troad to Crete. All
profess to represent the civilisation of the yEgean area at a
period removed by several centuries from the point at
which the Hellenic world emerges into history ; and the
traditional chronology of historical Hellas went up to an
era which is slightly later, but approximately contemporary
with the latest episodes of the Epic poems. Now though the
lays which display the greater literary skill and the maturer
idiom give a less vivid and more conventional picture ; and
though occasional allusions occur to customs and beliefs
which are characteristic of Hellenic culture, those others
which Greek tradition reckons primary, namely, the Iliad
and the Odyssey, are obviously at close quarters with their
subject ; and if there is one thing certain about the civilisa-
tion of the "Homeric Age" thus described, it is that it
differs in nearly every important feature from that of the
" Hellenic Age" of historical Greece.

2. The Greeks, in fact, themselves regarded their earliest
literature as antedating the chronological limits of their
history, and already perceived that they belonged to a
different order of things. In particular, the ethnography
of the /Egean, preserved in an admittedly late and de-
generate lay, differs uniformly from that of historic Hellas as
far back as it can be traced, and those names are almost

PREHISTORIC MAN, ETC. 337

absent by which the Greek race was denoted historically ;
by its western neighbours as "EAXiji'tc, by its eastern neigh-
bours as 'laoveg (Javan). This inconsistency was attributed
by the Greeks themselves to a period of invasion and
migration analogous to that which broke up the Graeco-
Roman civilisation of the Mediterranean. Dorian,
Thessalian and Boeotian mountaineers were represented as
forcing the barrier, or descending from the highlands, of the
Balkans, bringing the old established " Achaean " civilisa-
tion to an abrupt close, and reducing the /Egean, and
mainland Greece in particular, to a chaotic and barbarous
state, the recovery from which is the dawn of the historical
Hellenic genius.

3. Some facts within their own experience went to
confirm this view. Here and there tribes retained the names
and the mode of life of the earlier age ; or a noble family
professed to trace its descent beyond the limits of current
genealogy, and to identify itself with a Royal house of
Achaean princes ; and here and there ruined fortresses
remained, or ancient tombs had been disturbed, which
seemed to confirm the description of Achaean splendour in
the ballads.

4. Thus much had been established from the beginning
of Greek History onwards, and had not been seriously
shaken by successive attempts to discredit the traditional
view. The theories that the lays are comparatively late
compositions, and that they stand in no close relation to
a pre- Hellenic age ; that the Achaean Age is an invention,
and the Period of the Migrations a hypothesis to explain its
inconsistency with the facts of historical geography, all
prove too much, and may be met with argument a ad
hominem from the same traditional data. No literary
critic of the Epic has yet purged himself of a sediment of
traditional preconception ; and, in proportion as one or
another has attempted to do so, he has been reduced to a
merely agnostic position.

5. Further, until very recent years, every attempt which
was made to elucidate the civilisation of the Homeric Age
by the monuments of early Greek civilisation rested upon

338 SCIENCE PROGRESS.

the assumption that the representations of dress, armour,
etc., of the sixth, fifth and fourth centuries B.C., were valid
illustrations of poems which at the latest belonged to the
seventh, and on an average were assigned to the ninth or
tenth century. The reason of this was that Homeric sub-
jects in Greek art are uniformly furnished with accessories
of the age of the artist, and that until the study of Classical
Antiquities began to be infected with the " evolutionary
notions " which had already long been current in all other
departments of Ethnography, the attention of students of
Greek art and culture was strictly confined to mature and
decadent art ; everything which could not be assigned to a
century subsequent to the fifth was either dismissed as
barbaric, or discounted as a " Phoenician importation " ; the
part which " Phoenician " fables, ancient and modern, have
played in the historical study of the Mediterranean area will
be considered briefly later on. Such, for example, was the
received opinion — so far as there was one — of such dis-
coveries of pre-Hellenic culture as those of M. Fouque's
expedition to the Island of Santorin (Thera, 1862), where, in
the course of a geological investigation, a primitive settle-
ment was found under a thick bed of volcanic debris, or of
those of MM. Salzmann and Biliotti (1868-71), who in
searching for antiquities in Rhodes found at Ialysos, for the
British Museum, a magnificent collection of early vases
which are now known to be Mykenaean, and second only in
quality and variety to those from Mykense itself. The
Santorin settlement was simply taken to confirm the legend
of the Phoenician colony of Kadmos (Hdt. iv., 147), and
the vases from Ialysos were explained as the barbarous but
immediate predecessors of those from Kamiros, were classed
with them as " Grseco-Phcenician," and were referred to the
seventh century, in spite of the absence of Egyptian objects
of the twenty-sixth Dynasty, and the presence of objects of
the eighteenth : a view which in certain quarters is not
yet quite extinct.

6. It was not till 1871 that Dr. Heinrich Schliemann
was enabled to execute his lifelong ambition of testing with
the spade the Greek tradition that the site of the Grseco-

PREHISTORIC MAN, ETC. 339

Roman town of Ilion was also the site of Homer's Troy.
The tradition had indeed been sorely handled by Deme-
trios of Skepsis, a local antiquary of the second century
B.C., on the geological ground that the Plain of Troy is of
recent alluvial formation ; and by other critics on the score
of inconsistency with the Homeric narrative. But the Bali
Dagh, the site suggested by Demetrios, and in fact the
only alternative, is far more inconsistent, and is put
absolutely out of question by Dr. Schliemann's discoveries.
In successive seasons (1S71-3, 1876-82) he laid bare not
one, but six cities, built one after another on the same site,
and forming an accumulation of walls and debris some
thirty feet deep ; and, among these, two additional layers
have been distinguished in the confirmatory excavations of
Dr. Dorpfeld, 1892-94. The latter, however, indicate that
Dr. Schliemann's earlier work was not, from the circum-
stances of the case, sufficiently closely watched throughout,
and that in some cases objects were probably picked up at
lower levels than those to which they properly belong. In
particular, it is not clear that the cache of jewellery and
plate known as the "Great Treasure of Priam" was not
hidden originally in a shaft of some depth.

7. Dr. Schliemann claimed as the Homeric Troy the
Second Town from the bottom, which had perished by fire,
and in which the " Great Treasure " was found. But the
Sixth Town, which Dr. Schliemann described as Lydian,
was shown by Dr. Dorpfeld in 1892-93 to be larger and
more important than was at first supposed, and to cor-
respond closely with the remains found subsequently at
Mykenae and elsewhere.

8. With the same purpose in view of testing the
Homeric tradition, Dr. Schliemann proceeded in 1875-6 to
excavate the citadel of Mykenae, in the Peloponnese, the
traditional centre of the Achaian feudal confederacy. Here
the results were equally unexpected, but no less confirma-
tory of the legend. A civilisation was brought to light
wholly un- Hellenic, but far from barbarous ; greatly in
advance of all but the latest layers of Hissarlik, and
presenting already the marks of decadence after a protracted

34o SCIENCE PROGRESS.

career. The pottery, the personal ornaments, and in fact
the whole cycle of the art, were at once recognised as
identical with those of Ialysos, while the stone-fenced
burial-place discovered just within the " Lion Gate" of the
citadel, with its six " shaft graves " and their enormous
wealth of gold vessels and ornaments, seemed ample con-
firmation of the legendary wealth of " golden Mykenae,"
and was proclaimed, in the first enthusiasm of the discovery,
as the tomb of Agamemnon himself. The further re-
searches which have been made almost continuously from
1886 onwards by M. Tsountas for the Greek Archaeo-
logical Society have confirmed in all essential points the
first general impression, but the discovery of later tombs in
the lower quarters of the town has made it possible to trace
an order of progress and to extend the limits of the period.
9. Subsequent excavations at Tiryns and Orchomenos
by Dr. Schliemann, and on a number of other sites in
Greece and the yEgean Islands by the Greek Archaeo-
logical Society and the foreign Institutes in Athens, have
demonstrated that this civilisation, which has acquired the
provisional name of Mykenaean, is widely represented in
the yEgean area and especially in its southern part ; that
its influence extended over the Central and Eastern
Mediterranean from Sicily to Cyprus; that it penetrated,
intermittently at all events, into Egypt, where its appari-
tion can be approximately dated, and whence it imported
much, and borrowed somewhat, but without losing its own
individuality ; and, most striking of all, that, after a long
period of apparently continuous maturity, it falls into a
sudden decadence ; leaving, to all appearance, just the same
gap between itself and the first traces of Hellenic Art,
as we have noted already, on the literary side, between
the Homeric Age and the beginning of Hellenic His-
tory. It should be further noted, however, that in the
last few years many facts have come to light, especially in
Attica, in Crete, and, most of all, in Cyprus, which seem to
indicate how that gap may eventually be filled. It is from
the pottery, almost without exception, that the leading
indications have been derived. Fragments of baked clay

PREHISTORIC MAN, ETC. 341

are practically indestructible, even though the vessels which
they composed have been shattered. Moreover, all the
unrefined varieties of clay, and many even of the best
levigated, present features by which their place of origin
may be recognised. Consequently, in this material,
modelling and decoration can be perpetuated as in no other
way ; and, what is more important, the intrinsic worthless-
ness of earthenware has often preserved it from the dis-
placement and destruction which almost inevitably overtake
objects of gold, bronze, and marble. The resulting pre-
ponderance of ceramographic references in the bibliography
which follows these notes must therefore be taken as
indicating the character of the evidence which is most
accessible, and of the method which has actually proved
most fruitful : not that the pottery really took so large a
place in primitive art as might be inferred from its actual
abundance, and its scientific importance.

10. Consequently the study of Early Man in the JEgean
has entered within a few years on a new phase, and pre-
sents the following problems: (1) To reconstruct in detail
the history of the Mykenaean civilisation ; its origin, its charac-
ter, range and influence, and its decline ; (2) to investigate the
causes of that relapse into barbarism, which both literature
and archaeology attest ; (3) to determine the ethnological
position of the race, or races, who originated, maintained,
and overthrew it, and their relationship with the historic
inhabitants of the same area ; and (4) as a special study, to
determine the relation in which the Hellenic traditions of
the Achaean Age, and the lays in which they were preserved,
stand to the civilisation which they certainly seem to com-
memorate, and which owes its discovery simply to the
application to them of a new method of criticism.

(1) THE FIRST KNOWN CULTURE OF THE EASTERN

MEDITERRANEAN.

1 1. Palaeolithic Man seems to have left no traces in the
Levant comparable with those in North Europe, or with
the plateau and upper-gravel flints of the Nile Valley. But
the scarcity of evidence is partly due to the indifference of

342 SCIENCE PROGRESS.

the natives to such objects, and to the almost complete
diversion of trained research into more obvious and attrac-
tive departments ; partly also to the comparative rarity,
except in Egypt, both of workable flints and of the high-
level gravels in which they are usually preserved. From
Greece itself only one palaeolithic implement is recorded
hitherto ; a flint celt from Megalopolis in Arkadia (Rev.
Arch., xv., 1 6 ff).

12. Neolithic Man, however, can be traced over the
whole area. Masses of hard crystalline rock are frequent
and accessible, and furnished implements of characteristic
types ; short full-bodied celts, more or less markedly
conical behind, and ground to a rather obtuse edge. Ob-
sidian was largely exported from Melos and Thera to the
neighbouring islands, and to the mainland of Greece, and
was worked up at Korinth and on several sites in Attica.
Jade of good quality was sent from Asia Minor outwards
across the yEgean ; but it is not yet clear whether the
source of the common green variety is in Asia Minor itself
or further east : the jade implements become commoner
eastwards, and the finest collection from anysingle neighbour-
hood is that brought by Mr. D. G. Hogarth in 1894 from
Aintab in N. Syria (Ashm. Mus., Oxford).

13. Tombs of this stage of culture have not been found
— or sought — in sufficient numbers to justify discussion or
to contribute any facts of importance. The necropolis of
Psemmetismeno in Cyprus, for example, contains besides
typical early Bronze Age tombs a still more primitive class,
in which the pottery is exceedingly rude, and the charac-
teristic red-polished ware of the early Bronze Age is
wanting ; but though bronze is absent, no stone implements
are present. On the other hand the few tombs recorded
as containing stone implements are brought down by their
general character well within the Bronze Age.

14. Exception must however be made in favour of the
Nile Valley, for Professor Flinders Petrie in 1895 found,
at Ballas and Nagada, both tombs and villages of an
invading race, apparently Libyan, which had brought the
art of flint working to unequalled proficiency, and remained

PREHISTORIC MAN, ETC. 343

almost ignorant of the copper which was already in fairly-
common use under the Sixth Dynasty, which immediately
preceded their irruption into Egypt. But the significance
of this discovery and of our very limited knowledge of the
Libyan people and their civilisation will be better discussed
at a later stage.

15. On the other hand, several Settlements of the
Neolithic Age have been examined. Typical is the lowest
town of Hissarlik, though it has actually yielded a few
simple copper weapons. The implements are of local flint
and imported obsidian, of green-stone and allied rocks from
the interior of the Troad, and of jade ; some of the common
green Anatolian, others of finer yellowish kinds {cf. the
specimen in Ashm. Mus. attributed to Melos), and one
small celt of the pure white variety which is not known
to exist native except in China.

16. The fortifications and house walls of the "First City"
are of very rough unhewn rubble ; its pottery is of local
fabric, made wholly without the use of the potter's wheel,
and almost uniformly tinted black by a carbonaceous pig-
ment, intentionally applied and accentuated in the burning ;
many of the forms are closely allied to those of the neolithic
and early bronze ages in Central Europe, and of the corre-
sponding deposits of Greece and Cyprus. This lowest
settlement is separated from the rest by a layer of natural
soil, which represents an interval during which the site lay
desolate ; it is therefore distinctly older than the succeeding
cities. But the advanced and special technique of the
Pottery of the First City, and the fact that, on Schliemann's
authority, copper implements already occur, indicate the end
rather than the beginning of the Neolithic stage ; and the
Neolithic evidence from elsewhere is best summarised here,
before going further in the series at Hissarlik.

17. Settlements of similar character, but each with its
own local peculiarities, occur (r) on an unexcavated site,
commanding the Bosphorus as Hissarlik commands the
Dardanelles. (2) On the " Kastri " near Achmet-aga in
Eubcea, a low hill fortified with earthworks and approached
by a hollow way, like the hill camps of the south of England.

344 SCIENCE PROGRESS.

(3) Beside Dombrena near Thebes in Central Greece : the
site has not been described, but neolithic implements are
very frequent : among them is a potter's burnisher of white
quartzite (Finlay Coll., 280. Athens). (4) On the Acro-
polis of Athens many implements and vases were entirely
confused by the levelling of the summit in the fifth century
B.C. ; on the south side (in the space afterwards known as
the UtXapyiKov) is a layer of neolithic pottery with obsidian
flakes and a potter's burnisher, almost wholly destroyed
by the recent excavations, and only preserved where it is
left to support the fragmentary walls of the Mykenaean
settlement. The material of the pottery is Ilissos mud,
not the Kerameikos clay of the Kephissos valley. (5)
Beyond the Ilissos, between Hymettos and the sea, the
exact site is unknown, potsherds are common on the surface.
The many stone heaps in this district seem to have been
accumulated from off the fields on to barren spots ; two,
opened south-east of Kara in 1895, were quite barren; a
tumulus north-east of Kara, surreptitiously opened, con-
tained a Mykenaean interment (Ashm. Mus.). (6) Primitive
pottery is common on the west end of the cliff which runs
along the coast from New Corinth nearly to the site of
Lechaion.

18. The "Second City" of Hissarlik has marked points of
similarity with the first, but represents a decided advance,
and has notable characteristics of its own. The walls, great
and small, are of better masonry below, and of sun-dried
brick above, with bonding courses and terminal uprights
(antae) of timber ; the centre of the fortress is occupied by a
" chief's house," consisting of three oblong buildings with
portico entrances at one end in a courtyard entered by a
covered gateway. The pottery is still of unlevigated clay,
and mostly hand-made ; it is no longer blackened as before,
but either left as it is, or covered with a red slip, which con-
tinues to occur in the layers above ; new and characteristic
forms appear, some peculiar, others again common to
Central Europe, to the Greek islands or to Cyprus.
Stone implements are still in common use, but copper and
bronze begin to be frequent though they are still of simple

PREHISTORIC MAN, ETC. 345

types. But the pre-eminent feature of the Second Town is
the discovery of more than one buried " Treasure " of gold
and silver jewellery and vessels, the latter certainly of
local manufacture, for the forms closely correspond with
characteristic types of the pottery.

19. The Second Town perished in a general conflagra-
tion, and the Third, Fourth and Fifth Towns above it
never attained to anything like its magnificence. They
mark, however, a gradual advance of civilisation and form a
transition, more and more rapid as it proceeds, towards the
Sixth Town, a quite distinct and well-marked settlement of
" Mykenaean " invaders, in which imported pottery, and
native imitations of this, occur alongside of fully developed
indigenous forms, which again recall in characteristic details
many Central European types. This Sixth Town is the
only one which can be even approximately dated chrono-
logically ; it is certainly prior to 1000 B.C., and need not be
later than 1 300 ; the Fifth and lower settlements must of
course necessarily be older than this.

20. It has been already hinted that the " Treasure of
Priam " may belong to a period somewhat later than the
Second Town, though not so late as the sixth or
" Mykenaean " Town. Whether this be so or not, we
have in the jewellery an early example, perhaps a prototype,
of the characteristic gold work of the Mykenaean Age ;
but if the " Treasure " is contemporary with the layer in
which it was found, the time limit for the whole series at
Hissarlik must probably be contracted downwards. In
any case we must believe that the earliest civilisation of
Hissarlik was not so wholly barbarous as appears at first
sight.

21. Imported objects found at Hissarlik indicate a wide
range of foreign connections. The fragments of porcelain
point to Egypt ; the lapis lazuli axe from a neighbouring
site, to Turkestan ; the silver vases probably to the eastern
half of Asia Minor ; the types of the bronze implements
alike to Cyprus and to the Danube Valley ; and the amber
to the shores of the Baltic. This wide commerce does not,
of course, imply direct intercourse, but, from its geographical

346 SCIENCE PROGRESS.

position on the Hellespont, Hissarlik must have been a
point of convergence for any trade between the East and
Europe, and the catalogue of the allies of the Trojans in Iliad
II., though it refers to a later period, ranges them (i) up
the Hebros Valley into the Balkans, and along (2) the
North and (3) the West coast of Asia Minor; i.e., along
three well-known routes of early trade.

22. The metallic objects of Hissarlik are of particular
value as links between two principal copper-working areas,
Cyprus and Central Europe. The latter really falls
beyond our present view, but must be noted — mainly to be
rejected — as a possible source of the early Mediterranean
Bronze.

23. The use of copper in Cyprus goes back far beyond
the point where it can be dated with any certainty, and
everything goes to show that, while southwards, namely,
in Egypt under the Fourth Dynasty, Cypriote types appear
from the first side by side with others which are
probably Sinaitic, northward the same types extend, past
Hissarlik, into the Danube Valley, and are imitated and
amplified into derivative forms throughout Central Europe ;
returning, almost unrecognisable, into the Mediterranean
area in the series from Spain, which is clearly not directly
derivative, and may be of comparatively late origin.

24. The obvious suggestion that Central Europe may
have worked copper independently is met (1) by the com-
parison of the secondary forms, — e.g., only in Cyprus can the
actual synthesis of double-bladed axe heads, by welding
two simple ones, be observed ; (2) by the fact that, along
with the characteristic and indigenous metallurgy, the
ceramic technique of Cyprus, with red hand-polished sur-
face and incised ornament filled with white earth, can be
traced across Asia Minor and into South-eastern Europe ;
the red slip as far as Brus in Transylvania ; the ornament
into the Mondsee of Lower Austria, and the pile-dwellings
of Switzerland, becoming ever more mongrel and degenerate
as it proceeds.

25. It is important to note that at Hissarlik a return
current is already evident ; the pottery and the metal im-

PREHISTORIC MAN, ETC. 347

plements reproduce European types as well as Cypriote,
and this is confirmed, not only by traditional and
ethnological considerations, but also by the occurrence,
somewhat later, in the yEgean area, not only of frequent
amber, but of characteristically Danubian types of bronze
implements.

26. The Bronze Age civilisation of Cyprus is, thanks to
repeated researches, far more continuously and completely
known than any other part of the area. It was undoubtedly
of very long duration, and certainly follows that of the
Stone Age without change or break ; and it is no exaggera-
tion to say that, until a period between the twelfth and the
eighteenth Egyptian Dynasty, Cyprus was in all essential
respects in advance, not only of the coasts of Asia Minor
and the /Egean, but even of the coast of Syria and
Palestine.

27. All the earliest weapons, whether in Cyprus or
elsewhere, in Egypt, or the Levant, are of almost pure
copper. Tempering is effected, not by alloying with zinc or
tin, or, as in the Caucasus, with antimony from the natural
double-sulphide ore, but by " under-poling " the copper so
as to leave it hard and even brittle from the presence of
copper oxide. The same applies to the Egyptian copper
weapons of the fourth, fifth, and even sixth Dynasty ; but
Egypt, though later on it has important connections with
Cyprus, obtained its first copper from the mines of Sinai,
and has a set of typical forms peculiar to itself. Cyprus,
however, supplied the Syrian coast with copper weapons
down at all events to the time of the eighteenth Dynasty.
Stone implements are very rarely found in Cyprus,
and it is possible that either the island was not reached
much before the beginning of the Bronze Age, or that its
wealth of copper was discovered at once, and superseded
the stone age prematurely. In its earlier stages metallic
implements are rare, and the pottery — always made by
hand — is covered with a bright red glaze which was polished
with a stone or bone rubber (horse teeth were commonly
used), and ornamented, if at all, either by incised lines or
by pellets of clay rudely modelled after plants, snakes and

348 SCIENCE PROGRESS.

horned animals. In its earlier part, therefore, the civilisa-
tion, so far as it is known, is peculiarly uniform in character,
and displays no trace of foreign influence ; except only that
the characteristic red-polished glaze of the pottery, already
mentioned, is almost identical with that of the Neolithic
Libyan people of Ballas-Nagada, and of their " Amorite "
kinsfolk in South Palestine. Even here, however, there is
no evidence at present of imitation on either side. The
strong influence which Cyprus exercised, through its copper
trade, over the neighbouring coastland is best illustrated
by the discoveries of Dr. Bliss at Tell-el-Hesy, on the
coast plain of Palestine (Philistia), some sixteen miles from
Gaza. The site consists of an acropolis with eight "Cities "
superimposed as at Hissarlik. The mass of the remains
represent an indigenous "Amorite" civilisation of low type,
related, according to Professor Flinders Petrie, to that
of the Libyan invaders of Ballas-Nagada. But bronze appears
from the bottom of the series upwards, and iron already in
City Four, which with City Three appears to be contemporary
with the eighteenth Dynasty and the Mykenaean Age.
The bronze types are derivative, partly from Cyprus, partly
from Egypt ; and Cypriote importations of the later painted
fabrics occur in Cities Two and Three together with native
imitations. The red-polished pot fabric of Tell-el-Hesy,
however, belongs to the Amorite civilisation, and is not
necessarily borrowed from that of Cyprus.

28. In the latter half of the Bronze Age, Cyprus with
characteristic conservatism fell for a while slightly behind
its neighbours, and began to import ornaments and articles
of luxury from Egypt and the Syrian and Cilician coasts.
In this stage the red-polished ware tends to deteriorate in
colour and finish ; the bronze weapons become more
numerous, and contain a higher percentage of tin, and
occasionally jewellery of coarse silver-lead, all of native make,
is found in the more richly furnished tombs. Babylonian
cylinders occur rarely as imports, with a multitude of charac-
teristic native cylinders. Egyptian scarabs and porcelain
beads are also found rarely ; and with these again a very
common variety of coarse crumbly porcelain badly glazed

PREHISTORIC MAN, ETC. 349

with a very faint blue : the pigment was evidently difficult to
obtain, and was used but sparingly by the native artist.
But meanwhile the discovery of the art of ornamenting the
natural surface of clay vessels with an encaustic umber pig-
ment, wherever it may have originated, seems to appear
in Cyprus (where umber is extensively worked) at least
as early as anywhere else ; first in company with, but later
almost wholly superseding, the older mode of incising linear
ornaments on a prepared and polished surface.

29. The simply painted pottery is followed, though not
immediately, by several other fabrics which, though probably
native to Cyprus, are represented in some quantity on
Egyptian sites of the twelfth Dynasty and later dates, and
also in equivalent layers in the stratified mound of Tell-el-
Hesy, in the "Hittite" Sinjirli, and sporadically else-
where ; one very characteristic variety, with dark body,
white chalky slip, and black almost glossy paint, has been
found even so far afield as the Island of Thera, the Acro-
polis of Athens, and the " Sixth City" of Hissarlik.

30. The specimen from Thera was found in company
with vases of a distinct and local style ; some still with
coloured surface and incised ornament, others with simple
painted patterns. The forms, however, and the whole
fabric, are quite distinct from those of Cyprus, and show a
graceful freedom which is quite new; though they are clearly
derivative from a ceramic of the Hissarlik type. Most
important of all, the wholly geometrical and mainly linear
ornament which has been hitherto universal is combined
with or replaced by a thoroughly and vigorously natural-
istic study of animal and vegetable forms, and, in combina-
tion with the latter, spiral motives appear, hitherto unknown
but destined to a long and eventful career. These naturalistic
and curvilineardesigns are notonlyrepresentedon the pottery,
but are also frescoed upon the plastered walls of the houses ;
they may consequently be taken to be locally characteristic.
The settlement at Thera was found beneath a thick bed of
volcanic debris, and had evidently been suddenly abandoned ;
metallic objects are rare, but this may well be due, as M.
Tsountas suggests, to the flight of the inhabitants — for no

350 SCIENCE PROGRESS.

skeletons were found ; and a few copper implements and
gold ornaments remained to confirm the inference from the
pottery as to its position in the series.

31. Settlements and tombs of the same character have
since been noted in many islands of the Archipelago, especi-
ally in Syros, Melos, Antiparos and Amorgos ; and this
" Cycladic " type of ornament and general civilisation is not
only closely paralleled by the earliest remains at Mykense,
Tiryns, Athens and elsewhere, but is connected by an
almost continuous series with the fully developed art and
civilisation of the Mykensean Age itself.

32. It should be noted that though Cyprus appears to
have exported its own manufactures to the yEgean during
this period, it was not in a position to influence or direct
the Cycladic culture. But still less is there any trace that
the younger and more vivacious school reacted at all upon
the elder ; this was reserved for the full-grown culture of
Mykense.

2,7,. It is at this period that the Cretan evidence, though
as yet miserably incomplete, becomes of crucial importance.
Crete shares, to begin with, the early bronze age civilisa-
tion of Hissarlik and Cyprus, resembling the latter more
closely ; but it is not till the Cycladic stage is reached that
we have more than the most fragmentary evidence. In the
Cycladic period and in the succeeding age Crete was almost
literally tKaro^woXiQ, the " island of an hundred cities," and
certainly exercised a vigorous and continuous, perhaps even
a predominant influence upon /Egean civilisation. At this
point the wealth and variety of Cretan decorative art become
conspicuous, and a chronological point of the very first im-
portance and a clue to the origin of some characteristic
motives are given by the recent demonstration of a frequent
and fertile intercourse with Egypt in the time of the twelfth
Dynasty. On the one hand, a very peculiar and local fabric
of pottery from Kamarais in Crete has been found in twelfth
Dynasty layers at Kahun ; on the other, the Cretan types
of bronze implements are typically Egyptian, and twelfth
Dynasty scarabs were not only frequently imported, but
commonly imitated. In fact it is very probably from this

PREHISTORIC MAN, ETC. 351

quarter that the spiral motives, which are dominant in the
Egyptian Art of the twelfth Dynasty, were introduced into
the decorative repertory of /Egean art.

34. The seal-stones engraved with Egyptian and deriva-
tive spirals are closely associated in Crete with others
bearing groups of symbols, more than eighty of which have
been recorded, and shown to be hieroglyphic, by Mr. A. J.
Evans. They exist in two series, of which the earlier is fully
pictorial and naturalistic, the later conventionally abbre-
viated into linear forms. Some of the former are closely
analogous to certain Egyptian, others to certain " Hittite "
hieroglyphs from Kappadokian monuments ; many of
the latter are identical with graffiti on twelfth-eighteenth
Dynasty pottery from Kahun, Tell-el-Hesy and elsewhere,
and some are probably prototypes of symbols which per-
sisted in the Phoenician, Greek and Lykian alphabets, and
in the Cypriote syllabary. This hieroglyphic system is not
confined to Crete, though it is far best represented there
as yet ; the pictorial seal-stones are distributed over the
Cycladic area ; and two inscriptions in the linear character
have been found on vases at Mykenae. Dr. Kluge, of
Magdeburg, believes that he can translate these hiero-
glyphic inscriptions into a dialect of Greek.

35. We now come to what is, even literally, the Golden
Age of the early Mediterranean cycle. " Mykensean " Art
is still best and most completely illustrated by the long
series of discoveries in the plain of Argos, which at once
revealed its existence, and have given to it a name. The
monuments and the civilisation of Mykenae and Tiryns
have been repeatedly, though never yet really adequately,
described, and have given rise to the most divergent
theories as to their date, their origin, and their relations
with what precedes and follows them. The following
points are those which are chiefly made clear by the most
recent researches.

36. The limits within which Mykensean sites are dis-
tributed may now be defined with some approach to
accuracy, and no less the wider area over which Mykenaean
civilisation had a living influence. With the exception of

25

352 SCIENCE PROGRESS.

the "Sixth City" of Hissarlik no Mykenaean settlement is
known on the mainland of Asia Minor. Isolated vases are
reported from Pitane in JEoYis, from Mylasa in Karia, and
from Telmessos in Lykia, and the early necropolis of
Termera (Assarlik) near Halikarnassos (Budrum), though
of distinctly indigenous character, is strongly influenced, at
the very end of the period, by late Mykenaean models from
the neighbouring islands. Among the latter, besides the
great settlement at Ialysos in Rhodes, every island appears
to be represented from Rhodes southwards to Crete, and
northwards as far as Patmos. Both in Melos and in Thera
Mykenaean settlements are found distinctly superimposed
on the Cycladic already mentioned, and others are indicated
by isolated finds throughout the Archipelago. On the
mainland of Greece, Lakonia is represented by two sites
Kampos and Vaphio (Amyhlae), the latter with a princely
"beehive tomb" like those of Mykenae ; Argolis by
Mykense, the Heraion temple-site, Tiryns, Nauplia,
Trcezen, Epidauros, and the islands Kalauria and ^gina ;
Attica by Athens, Eleusis, Acharnae (Menidi), Aliki, Kara,
Spata, and Thorikos ; the rest of Central Greece by
Megara, Antikyra, Thebes, Tanagra, Levadia, Orchomenos
and several smaller sites in the Kopais marshes; North
Greece by Pagasae (Dimini near Volo) in Thessaly.

$*]. In the West there are no Mykensean settlements
known further than Kephallenia and Ithaka; but Mykensean
vases occur in domed rock tombs at Syracuse, and there is
much indirect evidence of Mykenaean influence on the later
Bronze Age style in Sicily and South Italy. Further than
this, it is clear that on the Adriatic coast of Italy Mykenaean
imports and models determined the character of the later
Bronze Age, and that in the transition from Bronze to
Iron at Hallstatt in the Tyrol, a definitely Mykenaean strain
can be detected. But in both these cases the contact is
with later and already quite decadent types, such as are re-
presented in the Lower Town of Mykenae ; in particular
fibulae are always present, and of these the secondary and
distinctly Sub-Mykenaean types are only very rarely absent.

38. Eastwards, Mykensean imports are found frequently

PREHISTORIC MAN, ETC. 353

in Cyprus, in the latest class of Bronze Age tombs,
and give a very distinct character to the necropoleis
of Episkopi (Kurion), Enkomi (Salamis), Pyla, Niko-
lidhes, and Laksha-tu-Riu. Native imitations increase in
frequency, and eventually supersede the importations and
fix the leading features of the art of the early Iron
Age, e.g., at Kuklia (Paphos), Lapathos and Katydata-
Linu. In Egypt again, Mykenaean importations are found
in great quantity, associated with the later Cypriote fabrics
and stimulating copious native imitation in layers of the
eighteenth Dynasty at Illahun, Gurob, Tell-el-Amarna.
These last finds confirm the date already inferred from
the occurrence of eighteenth Dynasty scarabs and porcelain
ornaments at Ialysos and at Mykenae, and fix the general
chronology of the Mykenaean Age beyond all question. The
contrary opinion, that the Mykenaean civilisation immediately
precedes the Orientalising culture of the seventh-sixth
centuries, and consequently itself descends as late as the
eighth-seventh centuries, has been vigorously urged by a
few English students, but has long been abandoned by all
who have had first-hand experience of the conditions of
discovery. The premature contention that the fortress of
Tiryns was Byzantine deserves mention, but is obsolete.

39. It is in Egypt also, moreover, that the first notice
occurs of the actual peoples who transmitted the civilisation
in question, and this in a peculiarly suggestive connection.
In the fifth year of Merenptah (1225) and under Rameses
III. (1 1 80- 1 150) the western frontier of Egypt was seriously
threatened by a Mediterranean coalition, of which the
Libyans were the principal members, but which included
under the general description of " the peoples of the isles
of the sea " a number of tribes whose names, though much
distorted in the Egyptian hieroglyphic records, strongly
resemble those of Achaians, Danaans, Ionians, Teucrians,
Tuscans or Tyrrhenians, and perhaps Sicilians and
Sardinians. Neither these names, of course, nor yet the
apparent resemblance of their arms and furniture, as depicted
in Egyptian paintings, can give more than a plausible pre-
sumption of identity either with historical /Egean races or

354 SCIENCE PROGRESS.

with the representatives of Mykenaean civilisation. But the
analogies are on all sides so close, that the identification is
usually accepted, and that as soon as even the outlines of
the history and civilisation of Libya during the Bronze Age
are ascertained, we shall be in a position to formulate
the real relations which then existed between Libya
and the /Egean, and probably also to trace more clearly to
its source the very remarkable realistic instinct which dis-
tinguishes the art of the y^Egean from all contemporary
styles.

40. The sudden collapse of the Mykensean civilisation,
which was indicated to begin with, is roughly coincident with
the first appearance of Iron in common use in the Levant, and
the attempt has been made, though on no direct evidence,
to connect the two tendencies. All the facts go to indicate
that, so far as the Mediterranean area is concerned at all
events, iron makes its appearance first on the Syrian coast,
in the period which immediately succeeds the downfall of
Egyptian suzerainty in that area under the nineteenth and
twentieth Dynasties: e.g., at Tell-el-Hesy iron occurs down to
the fourth "City" (= eighteenth Dynasty). The ambiguity
of the Egyptian allusions under the eighteenth and previous
Dynasties makes any earlier date uncertain, and iron has
not been actually found in Egypt before the twenty-sixth
Dynasty, 650 B.C. In Cyprus, where the evidence is com-
pletest, and where abundant native ores have certainly been
worked from an early period, iron suddenly becomes very
common just at the point when Mykensean vases are ceasing
to be imported, but when, on the other hand, Mykenaean
conventions have already begun to influence profoundly the
native scheme of ornament. At Mykenae itself iron occurs
first as a " precious metal " and in the form of signet rings, at
the stage where decadence begins to be rapid, but it is not
put to practical uses till the moment where the series breaks
off, and the same is the case in other Mykenaean sites in
the iEgean ; one iron sword was found in the Vaphio " bee-
hive ".

41. Up the Adriatic again it is with the early fibulae and
quite degenerate Mykenaean art, that iron makes its appear-

PREHISTORIC MAN, ETC. 355

ance, at Novilara ; and at Hallstadt ; and here again, both in
tradition and among the finds, there is evidence that the
metal became established first as an ornamental rarity, and
only subsequently as a substitute for bronze.

42. But though in its principal centres Mykensean
civilisation has all the appearance of having been suddenly
and violently extinguished, this must not be taken to be
universally the case. In Argolis (at Tiryns, and the Heraion),
in Attica, and in Melos, for example, there is every reason to
believe that the Mykenaean civilisation survives, though in
very degenerate phases, into the period when Iron and the
characteristic art of the early Iron Age are already well
established ; and at Nauplia and the Attic Salamis, and
still more in Crete, in Karia, and in Cyprus, the stages may
be clearly traced by which, so far as in it lay, the Iron Age
took up its inheritance from the Age of Bronze. The
nature and the result of this transference are easily sum-
marised.

43. It has been already indicated, firstly, that through-
out the Eastern Mediterranean, in fact throughout the whole
range of the Mediterranean Early Bronze Culture, the
indigenous system of decoration is instinctively rectilinear
and geometrical ; secondly, that in the Cycladic area and
in the Middle Bronze Age a quite irreconcilable and purely
naturalistic and quite heterogeneous impulse appears ; and
thirdly, that the fully formed Mykenaean style, when it
appears, is, in spite of its far superior technical skill and
elegance, already beginning to stagnate in many depart-
ments ; the gem-engraving and modelling developing last,
and retaining their vigour and elasticity latest ; whereas
the ceramic decoration, which appears in its noblest
form at Thera and at Kamarais, is the first to exhibit the
conventional and mechanical repetition of a shrinking
assortment of motives. We may now add, fourthly,
that this failure of originality permitted of a recrudescence
of the rectilinear instinct which, though overwhelmed for
the time by the naturalistic and curvilinear principles, had
co-existed with them throughout ; and that both floral and
spiral motives, once allowed to repeat themselves without

356 SCIENCE PROGRESS.

reference to their models, are transformed automatically
into the latticed triangles and maeanders, which are the
commonplaces of rectilinear design.

44. At this point the survey must close, for now, on
geometrically engraved tripods, and geometrically painted
vases, appear Hellenic inscriptions in alphabetic characters.
Borrowed Oriental, and especially Assyrianising, motives
intrude themselves into the panels of the rectilinear orna-
ment, and attempts are made, however ineffectual, to
represent first animal and then human forms. Now, in the
development upward out of the " Dark Age," Hellenic
history begins to reckon onward from the Trojan Era and
from Olympic and kindred lists ; and Hellenic art no longer
forward from the eighteenth, but backward from the twenty-
sixth Dynasty.

LEVANTINE ETHNOLOGY, AND SUMMARY (to follow).

BIBLIOGRAPHY.

N.B. The references which follow are grouped under
the numbers of the paragraphs of the text. They only
indicate the primary researches and theories, and must be
compared with the fairly full references in Perrot and
Chipiez, Histoire de I Art. VI, La Grece Prehistorique,
1895, and with the current notices of discoveries scattered
throughout M. Salomon Reinach's invaluable " Chroniques
d'Orient " published in the Revtie ArchcEologique, of which
the years 1883- 1890 have been republished separately
(Paris, Firmin Didot, 1891).

6. Dr. Schliemann's Researches.

Schliemann. Ilios. (German and Englished.), 1881, (French
ed., including " Troja"), 1885, (German and English), 1884.
Atlas Troj. A Iterthumer (photographs), 1874.
Mycence ,, ,, 1878.

Ithaka, etc., ,, ,, 1879.

OrcJwmenos ,, ,, 1881.

Tiryns ,, ,, 1886.

SCHUCHHARDT. ScJiliemanii s Excavations (German, Leipzig,
1890); E. T. Macmillan, 1891.

PREHISTORIC MAN, ETC. 357

11. The Stone Age. Sp. LAMBROS. 'Ia-opiKa MeXeryj/xara

{Historical Essays), ch. i.
Dumont. Materiaux pour servir a Fhistoire primitive de

rhomme, 1872 (Finlay Collection). Revue ArchcEologique, xv.,

pp. 16-19, 356 ff., xvi., p. 359 (1867).
PAPPADOPOULOS. AiQwi) kiroyy) ev rfj Mifcpa ' Aa'ia (Stone

Age in Asia Minor), Smyrna, 1875. Cf. Bulletin des

Correspondances Helleniques, ii., p. 8, 1876.
FlNLAY. UapaTtipriaei<i {Observations), Athens, 1869.

13. Psemmatismeno. DtJMMLER. Athenische Mittheilungen, xi.,

pp. 214-6, 1886.
Bronze Age Tombs with Neolithic Implements. At Kurion in
Cyprus. Archives des Missions, xvii., p. 6. Cypr. Museum
Catalogue, No. 470 (Oxford, 1 896). At Tiberiopolis in Phrygia.
J. A. R. Munro. Journ. Roy. Geog. Soc. (forthcoming).

14. Ballas-Nagada. Catalogue of Exhibits, University College,

London, July, 1895; Academy, 20th April, 16th July,
1895 (Report forthcoming).

15. Jade. SCHLIEMANN (Maskelyne). Ilios. (English), p. 240.
FISCHER. Neplirite u. Jadcite . . . uach Hirer Urgesch. u.

Ethnogr. Bedeutung, Stuttgart, 1875.
Davies. Geol. Mag., second decade, v., 4, April, 1878.

16. Hissarlik, v. § 6, SCHLIEMANN.

NORMAND. La Troie d'Homere (popular, well illustrated).

17. Thymbra. SCHLIEMANN. Ilios. s. v.

Boz-oyuk (Phrygia). Jahrbuch d. K. Akademie, Berlin, xi.,

1896. Anzeiger, p. 34.
Salonika. Jahrbuch, I.e.
Thessaly. Mitth. Ath., p. 99 ff., 1884.

18. Bceotia. Jahrbuch, 1895. Anzeiger, p. 32.

J.H.S., pp. 54-56, figs. 10-13, 1884.
Attica. Mitth. Ath., p. 138, fig. 31, 1S93.
Jahrbuch, p. 16, 1893.
22ff. MUCH. Die Kupferzeit in Europa (second edition), Jena, 1893.
Naue. Die Bronzezeit auf Cypern. Korresp. Blatt, p. 124, 1888.
VlRCHOW. Zeit. d. Deutsch. Gesellsch. d. Anthrop., xii., 73.

27. Copper and Early Bronze with but little Tin. J. H. GLADSTONE.

Proc. Brit. Ass. (Nottingham), p. 715, 1893. Trans. Soc.
Bibl. Archeology, xii., pp. 227-234. Flinders Petrie.
Zeitschr. f. Ethu., p. [477], 1891. BLISS, I.e.
Tell-el-Hesy. BLISS. A Mound of Many Cities, 1894.

28. Cyprus. Sandwith. Archcsologia, 1877.
DtJMMLER. Mitt. Ath., xi., 1886.
OHNEFALSCH-RlCHTER. Kypros the Bible and Homer, 1892.

358 SCIENCE PROGRESS.

Myres and OHNEFALSCH-RiCHTER. Cyprus Museum Catalogue,
Oxford. 1896 (in the press).

30. Thera. FOUQUE. Santorin. Archives des Missions, ser. 2,

vol. iv.

31. Cyclades. Dummler. Mitth. Ath., xi., 1886.
Antiparos. Bent. /. H. S., x., 1887.

33. Crete. A. J. Evans. Journ. Hellenic Studies, xiv., pp. 276-372,

1894 (republ. "Cretan Pictographs," etc., Quaritch, 1895).

34. y£gean Hieroglyphic System. Evans, I.e.
KLUGE. Magdeburger Zeitung, 1896.

35. Mykenaean Civilisation in general. v. Bibliogr. in PERROT,

vi., q.v.
TSOUNTAS. Mvxrjvai fcal Muk. ttoXlthtpos (Mykenae and

Myk. Civilisation), Athens, 1893.
TSOUNTAS. sE^>rffi€pU 'ApxaioXoyL/cr) {Journal of Gk. Arch.

Soc), 1 886- 1 894, passim.
PERROT and Chipiez. Histoire de I'Art, vi. (la Grece

Prehistorique) (E. T.), 1895.
FURTW/ENGLER u. LcESCHKE. Myk. TJiongefdsse, 1879.
FURTW^ENGLER U. LcESCHKE. Myk. Vasen, 1886.
POTTIER. Vases Antiques du Louvre, I., p. 181 ff., 1896.
HELBIG. La Question Myce'nienne. Paris, 1896.
^6. Mykenaean Sites, Asia Minor : —

Hissarlik, "VI." DCERPFELD. Troja, 1893. Mykenische
Vasen, p. n. Reinach. Rev. Arch., 1893, i., p. 357. Rev.

Arch., 1895, i., p. 1 13.
Pitane (zEolis). PERROT, vi., Fig. 489-91.
Lemnos. Rev. Arch., xxvii., 1895, Nov. -Dec. ; cf. Smyrna

Museum.
Telmessos. Mitth. Ath., xii., pp. 228-230.
Thessaly. WOLTERS. Mitth. Ath., xiii, p. 262, PI. viii.-xi., 1889.
Orchomenos and neighbourhood. SCHLIEMANN, q.v. De

Ridder. B. C. H., p. 137 ff., 1895. Esp. Gha. De Ridder.

B. C.Lf.,p. 271 ff., 1894. Noack. Mitth. Ath,, xix., 1894.
Daulis. {Athens: National Museum), unpublished.
Antikyra (Phokis). Lolling. Wolters' Mitth. Ath., xiii.,

p. 267, 1889 (identified with Medeon).
Athens. TSOUNTAS. *E<f>. 'Apx-, 1891, p. 27 ff.

GR/EF. Jahrbuch, 1892. Anzeiger, p. 16 ff.
Wide. 'Adtjvcuop, ii., 1895, 168.
Eleusis. Philios. 'Ecp. 'Apx-, 1889, p. 171.
Koropi. Bruckner. Mitth. Ath., xvi., p. 200 ff., 18

(identified with Pallene).
Sal am is. (Athens: National Museum.)

PREHISTORIC MAN, ETC. 359

/Egina. Evans. /. H. S., p. 195 ff., 1892-93 (Gold-find).

Reinach. Rev. Arch., November-December, 1895.
Kalaureia. Wide. Mitth. At//., xx., p. 297, 1895.
Troezen. Reinach. Chroniques, p. 628.

Epidauros. [Athens: National Museum.) 'Apx AeXrlov, 1888.
Kephallenia. Wolters. Mitth. Ath., xix., pp. 486-490.
Crete. Milchhcefer. Die Anfange d. Kunst, p. 122 ff.
Evans. /. H. S., xiii., pp. 276-372, 1894 (republ. "Cretan

Pictographs," Ouaritch, 1895).
FURTW.ENGLER u. LCESCHKE. Myk. Vaseil, pp. 22-4.
Halbherr and ORSI. Museo Italiano, II., p. 908, pi. xiii.-xiv.
Haussoullier. B. C. H., 1880, pp. 124-7.
Joubin. B. C. H., 1892, p. 295.
ORSI. Monumenti AnticJii d. Accad. d. Lincei, I., p. 201 ff.,

1890.
Perrot, vi., p. 451 ff. (bibliography).
Sicily. ORSI. Bulletino di Paletnologia Italiana, xviii., pp.

193 ff., 206 ff , xx., p. 257 ff. Necropoli Sieu/a, p. 30 ff.
Spain. GASCON de GOLOS. Saragoza, i., pi. iii., p. 40.
39. Chronology — For eighteenth Dynasty dates : —

Flinders Petrie. /. H. S., xii., pp. 199-205, 1891.
Perrot, vi., p. 1000 ff.
For later dates (summary) : —
REINACH. Chroniques, pp. 420, 575 ff Rev. Arch., p. 75, 1893.

Classical Review, p. 462 ff, 1892. Times, 6th January, 1896.

Academy, nth January, cf. 1st February, 1896.
Torr. Memphis and Mykence. 1896.
For " Byzantine " Tiryns (summary) : —

Reinach. Chroniques, p. 280 ff, V Anthropologic, p. 701, 1893.

J. L. Myres.

THE GRAPTOLITES.

THERE is, perhaps, no better illustration in geology of
the value of detailed work than that which is fur-
nished by the group of organisms, to the consideration of
which this article is devoted. Formerly viewed with sus-
picion by biologist and geologist alike, and frequently
altogether ignored, we find the graptolites now treated
with respect even by those who have not devoted special
attention to them. Their value is generally recognised as
aids in the determination of the age of strata, but besides
this, a detailed study of the group will undoubtedly throw
light upon the physical and climatic conditions under which
the strata containing graptolite remains were deposited, and
also upon the evolution of the various forms of graptolites.
Every one will admit that the appreciation in which grapto-
lites are now held is largely due to three papers by Professor
Lapworth, one of which treats of these organisms from a
biological (i), and the second (2) and third (3) from a
stratigraphical point of view ; and the publication of these
papers is doubtless largely responsible for the appearance
of a large number of memoirs devoted to a study of the
group under consideration which have been written of
recent years. These recent memoirs it is the object of
this paper to consider.

The memoirs, early and more recent, treating of the
graptolites are scattered through a variety of publications,
but an excellent bibliography compiled by Otto Herrmann
and published in his Inaugural Dissertation (4) gives a list
of these memoirs up to and including the year 1883. Even
with this guide the student has much difficulty in obtaining
access to some of the publications, and a general monograph
of the graptolites has yet to be written. In the list of
" Monographs which are promised or are in course of
publication " appended to the last " Monograph of the
Palaeontographical Society" we note "The Graptolites," by
Professor Lapworth, and all geologists must hope that ere

THE GRAPTOLITES. 361

long the professor will give to the world the full results of
his prolonged researches into the history of the group.
This monograph must necessarily be confined to an account
of the British graptolites, but when that is complete surely
Professor Lapworth will treat of those of other countries
also.

The graptolites, at one time referred by some writers to
the Hydrozoa, by others to the Polyzoa, are now generally
admitted to belong to the former class, though the exact
value of the sub-division is not definitely settled, for whereas
we find Professor von Zittel in his Paleontology treating of
them as a sub-order, Graptolithidse (= Rhabdophora, All-
man), divided into the groups Graptolitoidea Lapw. and
Retioloidea Lapw., Nicholson and Lydekker {Manual of
Paleontology) place them in a sub-class (Graptolitoidea).
In these works the general structure of the graptolites is
described, though, as will be seen in the sequel, one structure
supposed to be absolutely characteristic of all graptolites,
namely the virgula, is not really so. Comparatively little
has been added to the knowledge of the histology of the
graptolitoidea furnished by H. Richter (5), though some of
his results have been confirmed by Professor Sollas (6) ;
and additional information has been supplied by Professor
S. L. Tornquist (7) and Dr. Perner (8). Some of the most
important papers published of recent years treat especially
of the mode of growth of the proximal portions of the
graptolites. The first of these by Tornquist (9) is occupied
with a description of sections through several deprionidian
graptolites. The author distinguishes the obverse from the
reverse aspect of the polypary, and also introduces two
terms to distinguish its right and left portions — the " primor-
dial " portion, containing the "primordial" series of hydro-
thecae, is marked by the possession of the earliest hydro-
theca, whilst the other portion is termed the "second"
portion and possesses the second series of hydrothecse.
When the obverse aspect of the polypary is turned towards
the observer the primordial series of hydrothecae is in-
variably on the left hand. The sicula sends out what the
author terms a " connecting canal ' which opens into a

362 SCIENCE PROGRESS.

" biserial chamber," thus producing a connection between
the various parts of the polypary. These features are
common to all the forms described by the author, but the
forms differ in other respects. In Climacograptus scalaris
Linn, and Climacograptus internexus Tornq. the biserial
chamber communicates with two uniserial canals separated
from one another by a median septum. In Diptograptus
palmeus Barr. the septum scarcely extends through half the
thickness of the polypary, whilst in Cephalograptus cometa
Gein. it is " reduced to a narrow7 fold of the obverse peri-
derm," and in Diptograptus bellutus Tornq. it is altogether
absent.

Two papers by Wiman (10) treat of the structure of the
Diptograptidce and of Monograptus. Notices of these papers
by E. M. R. Wood and G. L. Elles appear in the Geological
Magazine for 1895, p. 431. The accounts of the structure
of the sicula, and of those parts of the polypary immediately
in contact with it, are largely confirmed by Holm in a paper
to be noticed immediately, but the statement that the Dip-
tograptida; are monoprionidian because the sicula gives rise
to only one bud (which is on the right hand side) involves
a special use of the term monoprionidian which will hardly
meet with general acceptance.

A most important paper by Gerhard Holm must now be
noticed (11). Holm has had the advantage of studying
some beautiful material derived from the J^aginatus-Yimestone
(of Areing age) from various localities in the northern part
of the Island of Oland ; the graptolites of this limestone he
has succeeded in freeing from the matrix, thus rendering
them serviceable for detailed study. (The method of re-
moving the matrix is described by Holm in an article in
Bihang K. Vetensk. Akad. HandL, Bd. xvi., 1890.) In the
present paper he gives reasons for supposing "that the
earlier development of the proximal part — the first three
thecae — in all the bilateral or diprionidian forms of graptolites
is in the main the same, and has taken place through the
formation of only one bud on one side of the sicula — -or first
theca, as I believe it is — which side is always the same in
relation to the later development of the polypary. From

THE GRAPTOLITES. 363

this bud thereafter is developed partly the second theca,
partly the canal — ' connecting canal ' — which connects both
halves of the polypary, and which in the first place gives
origin to the third theca (= first theca on opposite side of
sicula), and partly also the common canal which connects
the second theca with the succeeding ones." He describes
the " sicula " which consists of two distinct portions, the
"initial part" which he believes to correspond with the
original " chitinous covering of the free zooid germ or em-
bryo," and the apertural part which has the same function
as a theca and may therefore be justly considered as the
first theca. Accordingly Holm's second theca corresponds
to Tornquist's primordial one, and his third to Tornquist's
second.

The sicula in the bilateral graptolites does not occupy a
central position, being partly embraced on one side by the
connecting canal, whilst on the other side it is more or less
superficial. The sicula side is termed the "anterior," and
the other the "posterior". These are used in the same
sense as that in which Tornquist employs the terms "ob-
verse aspect" and "reverse aspect". The author gives a
full account of the connection between the sicula, the first
theca, the first bud, from which " arises almost simul-
taneously with the left theca the common canal for the
left half of the polypary, and the connecting canal which
crosses the dorsal side of the sicula and gives origin to the
third (or, better, the right) theca lying on the right side of
the polypary, and also the common canal for the right side
of the polypary," and describes the growth of these in
Didymograptus minutus Tornq., D. gracilis Tornq. mut., D.
gibberulus Nich., Tetrgraptus Bigsbyi Hall, and Phyllo-
graptus angustifo/ius Hall.

He maintains that a virgula cannot occur in any
graptolites of the families Dickograptida, Dictyogr apt idee,
and Nemagraptidce, or in the genus Dicellograptus of the
family Dic7'anogiraptid&. The true virgula commences
near the apex of the sicula as a prolongation of the same,
and corresponds with the thread-like prolongation of the
sicula which has long been known in Didymograptus

364 SCIENCE PROGRESS.

gibberulus, and certainly occurs in many other forms of
Dichograptidce. Another filiform appendage which might
be spoken of as the false virgula " originates as a result of
growth within the apertural end of the sicula at some
distance from the initial portion. This later structure
stands evidently in no relation whatever to the real
virgula, but may be regarded as an apertural spine." The
significance of these filiform processes has not yet been
fully explained, but the possession of a true virgula must in
future be omitted from diagnoses of the characters of the sub-
class or sub-order of the graptolites. Holm's researches
fully confirm Tullberg's inference that Phyllograptus belongs
to the family Dichograptidce, and the family Phyllograptidcz
must now be abandoned. Another interesting point bear-
ing upon classification is the position from which the bud
grows out of the sicula. " In Phyllograptiis it is situated
quite close to the apex of the sicula, in Tetragraptus
Bigs by i Hall probably slightly lower down, in Didymograptus
miniUus Tornq. somewhat below the middle of the
sicula, in Didymograptus gracilis Tornq. Mut. still nearer
the aperture ; but in Didymograptus gibberulus Nich. the
position is almost the same as in Pliyllograptus." The
reference of the genus Azygograptus to the Nemagraptidce
on account of the stipe being developed from the central
part of the sicula on one side is therefore unnecessary, and
the general characters of Azygograptus leave no doubt
that it belongs to the Dichograptidce ; indeed Holm in the
paper under consideration describes a form which is possibly
intermediate between Didymograptus and Azygograptus.

The association of a number of graptolites of the same
species in a fairly symmetrical manner has long been
known. James Hall in plate xiv. of his classic work on
graptolites (12) figures a diprionidian graptolite under the
name of Retiograptus teutaculatus, and in figure 9 is "an
illustration of a compound form of the genus," possessing
nearly twenty diprionidian stipes diverging from a common
centre. James Dairon (13) also figures specimens of
Monograptus occurring in partly symmetrical tufts, and
remarks : " I am now thoroughly convinced that many, if

THE GRAPTOLITES. 365

not all, of the specimens of Monograptus may have been
fixed to the sea-bottom, or to objects lying or growing on
it, and not have been free-floating organisms, as has hither-
to been supposed, until at last they were separated from
their points of attachment by breakage or some other
natural cause ". Recently a remarkable description has
appeared (14) giving an account of specimens of Dipto-
graptus pristis Hall and D. pristiniformis Hall from
the Utica Slates. In these specimens the stipes occur in
"compound colonial stocks which appear in the fossil state
in stellate groups ". From observations on the specimens,
the author infers "that the colonial stock was carried by a
large air-bladder, to the underside of which was attached
the funicle. The latter was enclosed in the central disc,
and this was surrounded by a verticil of vesicles, the
gonangia, which produced the siculae. Below the verticil
of gonangia and suspended from the funicle was the tuft
of stipes," the latter being so arranged that the " sicula-
bearing end of the single stipes appears in the compound
colonial stock as the distal one ". The paper is only an
abstract of one which is promised shortly, and geologists
will await with interest a full account of these remarkable
specimens. The structure described as a funicle can hardly
be looked upon as the analogue of the " organ" described
by Hall under that name (which by the way has been
proved by Brogger and Holm to be celluliferous in many
species, so that Holm is doubtless correct when he says
that a funicle has not been found in any graptolite). It
is remarkable that the author should explain what he
means by the assertion that the chitinous capsule which
encloses the " funicle ': on the specimens described is
identical with the "central disc ': of the compound
fronds of numerous Monogr apt idee, for no geologist, as
far as I am aware, has described Monograptidcc with com-
pound fronds, unless Dairon's specimens be taken as such.
The early writers on graptolites looked upon the num-
ber of stipes possessed by graptolites as a character of
prime importance in defining genera, such forms as Dicho-
graptus, Tetr agraphia, Didymograptus and Monograptus

366 SCIENCE PROGRESS.

being largely characterised by the possession of eight, four,
two stipes and one stipe respectively. In a recent paper
by Professor Nicholson and the present writer (15) we
have endeavoured to show that this is not the case, but
that the character of the hydrothecae and to a less degree
the amount of angle of divergence of the stipes are of im-
portance. We endeavour to prove that certain grapto-
lites underwent development along parallel lines, passing
through many-branched, eight-branched, four-branched,
two-branched and one-branched forms, thus illustrating the
principle of heterogenetic homoeomorphy advocated by
Mojsisovics, S. S. Buckman and others. If this be allowed,
many of the present genera will have to be abolished and
new ones formed ; but the writers earnestly advocate the
retention of the present genera under existing circum-
stances, and hope that the formation of fresh genera will
be deferred until our views are more fully developed or
perchance disproved, though we do not think that the latter
event is likely.

It will be noticed that the above researches into the
morphology of the graptolites deal mainly with the
celluliferous portions of the polyparies, whilst the study of
the various bodies referred to as concerned in reproduction
has not been largely pursued of recent years.

Passing now to the memoirs treating of the graptolites
as indices of age of the rocks which contain them, it may
be remarked at the outset that recent work has fully estab-
lished the correctness of the views advanced by Lapworth
in his papers on the Moffat series and on the geological
distribution of the Rhabdophora. Perner alone has stood
out for the anomalous occurrences described by the eminent
Barrande in the Bohemian basin, but he does not yet
appear to have studied completely the zonal distribution of
these organisms in that region, though he has added largely
to the number of species occurring in the Lower Palaezoic
rocks of Bohemia. The new species described here and
elsewhere of recent years it is not contemplated to notice in
this article, though they will doubtless give us much
information in addition to that we have already obtained

THE GRAPTOLITES. 367

concerning the morphology and phylogeny of the graptoli-
toidea. It would serve no useful purpose to give details of
the numerous papers which confirm the value of the grap-
tolites for purposes of correlation of the strata. In Britain,
Lapworth himself has described a number of graptolitic
bands interstratified with deposits containing the remains of
other organisms in Ayrshire (16). Much remains to be
done in this respect, for in order to utilise to the utmost the
value of these organisms as stratigraphical indices, it will be
necessary to have a complete correlation of graptolitiferous
strata of all ages, with those which contain these organisms
rarely or not at all. For this purpose all graptolites should
be carefully collected and preserved from out of those
deposits in which they are not frequent, and are associated
with other organisms. They should be looked for especi-
ally in calcareous deposits, for as we have already seen, such
specimens are particularly valuable as furnishing information
concerning the morphology of these fossils. The southern
uplands of Scotland have recently been re-examined by the
geological surveyors, and it is scarcely necessary to state
that they have fully confirmed Professor Lapworth's classifi-
cation of the Lower Palaeozoic Rocks of this region. In
England Professor Nicholson and the present writer have
defined graptolitic zones in the Skiddaw Slates, Llandovery,
Tarannon, Wenlock and Lower Ludlow Beds (17). Messrs.
Lake and Groom have detected the Monograptus gregarius
zone of the Birkhill shales and zones of Monograptus per-
sonalis, M. Flemingii, M. colonius and M. leint wardinensis
near Corwen and Llangollen (18), whilst in a paper which
has hitherto only appeared in abstract, Miss Wood and
Miss Elles have detected several zones of the Birkhill-Gala
beds near Conway. On the Welsh borderland W. W.
Watts has found one graptolitic zone of Wenlock and two
of Lower Ludlow age on the Long Mountain (19). In
addition to this, various other graptolitic zones have been
detected in different parts of Great Britain, and the zones of
the Moffat area have been traced into Ireland. On the
European continent, Linnarsson, Brogger, Tornquist,

Tullberg and others have detected numerous graptolite

26

368 SCIENCE PROGRESS.

zones in Scandinavia, a full account of which appears in
Tullberg's paper on the graptolites of Scania (20), one of
the most valuable of recent contributions to the literature of
the graptolites. Tornquist, Perner, Barrois and others
have also identified various graptolitic zones in Thuringia,
Bohemia and France. In North America the principal
contribution is by our own countryman, Lapworth, who has
identified a number of graptolite zones in Canada, which
are identical with those detected in Europe (21). In
Australia T. S. Hall is studying the well-known Areing
graptolite fauna, and finds that the graptolites here also are
limited to special zones (22). A number of other papers
might be quoted to show the general recognition of the
utility of graptolites for purposes of correlation of strata,
but enough has been said to indicate the manner in which
the work is progressing, and the vast amount which yet
remains to be done in this connection. I cannot leave this
part of the subject without uttering a warning note. More
harm is done by a wrong determination than good by a
correct one. The graptolites are by no means easy of
identification by those who have not made them a special
study, and it is particularly desirable that no determination
should be recorded by tyros, unless it is absolutely certain,
for when once a wrong name has crept into a list it is
exceedingly difficult to remove it. I could give several
instances of very serious mistakes of this kind which have
been made, each of which will have to be corrected else-
where, but it would be invidious to give names in a
general article of this character.

We may now pass on to consider the physical conditions
under which the graptolite-bearing strata were deposited.
There is very little doubt that they were formed in water of
very different degrees of depth, for graptolites are found in
arenaceous, argillaceous and calcareous strata. Thev have
mainly been collected from deposits which there is every
reason to suppose were formed in deep seas, because a much
greater number of individuals occur in a given space under
such conditions than when the deposits were formed rapidly.
The writer has elsewhere given cases of graptolitic deposits

THE GRAPTOLITES. 369

a few feet in thickness, being represented by thousands of
feet in adjoining regions, and one naturally discovers
forms more easily in a few feet of strata than in several
thousand feet where the process of search rather closely
approximates to that for the proverbial needle in the hay-
stack. The evidence which is being gathered shows more
strongly than ever that the thin graptolite-bearing shales,
which for the above reasons have come to be looked upon
as the deposits for graptolites /di?'- excellence, were deposited
slowly in waters some distance from continents, and pro-
bably of considerable depth. The evidence for depth
depends mainly on the nature of the associated organisms,
which are frequently dwarfed, and either blind or with
enormously developed eyes, whilst that for deposition at
a distance from land is confirmed by the ever-increasing
number of cases of association of graptolitic deposits with
others which are composed almost exclusively of tests of
radiolaria. The most striking" case of this has recently
been detected by the geological surveyors amongst the
rocks of the Southern uplands of Scotland (23). Messrs.
Peach and Home have there discovered beds with Tetra-
graptus of Middle Areing Age, separated from beds with
characteristic Glenkiln (Upper Llandeilo) graptolites by a
thin deposit of radiolarian chert. " We thus perceive that
the great mass of strata which elsewhere forms the Upper
Areing, and the Lower and Middle Llandeilo formations
are here reduced to not more than sixty or seventy feet.
Judged by the palaeontological evidence these thin cherts
appear to be a chronological equivalent of thousands of feet
of ordinary sediment in North Wales. They, no doubt,
were deposited with extreme slowness in a sea of some
depth, and over a part of the sea-floor which lay practically
outside the area of the transport and deposit of the terres-
trial sediment of the time."

The graptolites are generally viewed as type-fossils of
the Lower Palaeozoic rocks, and this view is practically
correct. The earliest graptolite which has hitherto been
described, Dichograptus ? tenellns Linnrs., occurs in the
Lingula Flags of Sweden, below the shales with Dictyo-

370 SCIENCE PROGRESS.

graptus flabelliformis Eichw. which are so widely distributed.
This Dictyograptus, by the way. which has a very limited
vertical distribution, is probably in no way related to the
long-ranged Dictyonema. Graptolites are extremely rare
in the Upper Ludlow rocks, and have been detected in the
Lower Devonian rocks of Bohemia, though it is doubtful
whether their asserted occurrences in rocks of Devonian
age in Scotland and the Harz Mountains are correct. It
may be taken as fairly certain that they finally died out in
Devonian times. Between the earliest and latest graptolitic
deposits we have already a large number of graptolitic zones,
which it will be of use to print in one connected list as this
has not been heretofore done. So far as they have been
made out they are, in ascending order, as follows : Lingula
Flags ; (i.) Zone of Dichograptus? tenellus, Zone of Dictyo-
graptus flabelliformis. Tremadoc Slates; Zones of Bryo-
graptus. Areing Beds ; Zones of (i.) Dichograptus, (ii.)
Tetragraptus, (iii.) Didymograpttts indentus var nanus.
Llandeilo Beds; (i.) Zone of Didymograpttts Murchisoni,
(ii.) Zone of Ccenograpttis gracilis. Bala Beds; Zones of
(i.) Climacograptus Wilsoni, (ii.) Dicranograptus Clingani,
(iii.) Pleurograptus linearis, (iv.) Dicellograptus complana-
tus, (v.) Dicellograptus anceps. Llandovery Beds ; Zones of
(i.) Diplograptus acuminatus, (ii.) Diplograptus vesiculosus,
(iii.) Monograptus argenteus, (iv.) Monograptus convolutus,
(v.) Cephalograptus cometa, (vi.) Monograptus spinigerus,
(vii.) Rastrites maximus. Tarannon Beds ; Zones of (i.)
Monographts turriculatus, (ii.) Monograptus exiguus, (iii.)
Cyrtograptus Graycz. Wenlock Beds; Zones of various
species of Cyrtograptus not yet fully worked out. Lower
Ludlow Beds; Zones of (i.) Monograptus bohemicus, (ii.)
Monograptus Alilssoni, (iii.) Monograptus leintzvardinensis.
Upper Ludlozv and Lower Devonian ; Zones of undescribed
graptolites.

It is quite certain that this number will be very largely
increased as a result of further work, but it is sufficient to
show the importance of the Lower Palaeozoic rocks when it
is remembered that many of these Zones contain a fauna
largely distinct from the faunas of the adjoining ones.

THE GRAPTOLITES. 371

When the Zones are worked out more fully than is the
case at present, we shall have a far better gauge of " Geo-
logical Time " than that founded upon the crude estimates
made by measuring thicknesses of strata.

Lastly, the study of graptolites may possibly throw
some light upon climatic change. I have already en-
larged upon this elsewhere (24), and pointed out that the
separation of graptolitic deposits from non-graptolitic ones
amongst the Stockdale shales of the Lake District, the
deposits themselves being lithologically similar, is most
readily explicable by climatic change. The argument
would be stronger had microscopic examination and
chemical analyses of the strata been made, and I should
be glad to supply any one who cares to look into this
question, which is one of some interest, with material for
such examinations.

In conclusion, the above notes will be sufficient to
show the importance which the graptolitoidea have
assumed not only to the geologist but also to the biologist.
That they differ in any remarkable respect, as regards
their teachings, from any other group of fossils is doubtful.
Their special utility lies in the fact that owing to their
characters they are preserved in sufficient numbers to
allow collectors to obtain a large suite of specimens of
almost every species with little difficulty ; the result is that
further advance has been made in their study than in that
of many other groups which like them are only preserved
in the fossil state. One word to the biologists. We are
often told that fossils are of little use on account of the
absence of soft parts, though biologists have not been
much hampered by this when dealing with the Vertebrata.
But to compensate for the want of soft parts, we are furnished
with a countless supply of specimens whose order of appear-
ance and disappearance we are able to a large extent to ascer-
tain, and this is what the biologist can never obtain by con-
fining his attention to recent organisms. From them he has
been able to ascertain that evolution occurs; how it occurs
is left for the palaeontologist to describe. That the study
of these organisms as pursued up to the present has not

372 SCIENCE PROGRESS.

been in vain, is conclusively proved by the best of all tests,
namely, that we are able to predict the discovery of forms
which are afterwards detected by the worker in the field,
to whom we commend this group as one specially worthy of
his attention.

BIBLIOGRAPHY.

(i) LAPWORTH, Charles. Notes on the British Graptolites and
their Allies. I. On an improved Classification of the
Rhabdophora. Geol. Mag., vol. x., pp. 500 and 555,

1873.

(2) LAPWORTH, CHARLES. The Moffat Series. Quart. Journ.

Geol. Soc, vol. xxxiv., p. 240, 1878.

(3) LAPWORTH, CHARLES. On the Geological Distribution of

Rhabdophora. Ann. and Mag. Nat. Hist., ser. 5, vol. iii.,
1879.

(4) Herrmann, Otto. Die Graptolithen familie Dichograptidae,

Lapvv. Kristiania, 1885.

(5) RlCHTER, H. Thiiringische Graptolithen. Zcit. d. Deutsch.

Geol. Gesell., vol. v., p. 439, 1853.

(6) SOLLAS, W. J. On the Minute Structure of the Skeleton of

Monograptus priodon. Rep. Brit. Assoc., 1893, P- 7%l>
1894.

(7) TORNQUIST, S. L. Studier ofver Retiolites. Aftr. nr Geol.

Foren. i. Stockholm Forhdndl, Bd. v., 7, p. 292, 1880.

(8) Perner, J. Etudes sur les Graptolites de Bohbne. Prague,

1894.

(9) TORNQUIST, S. L. Observations on the Structure of some

Diprionidae. Sdrtryck of Konl., Fysiogr., Svesk., Handl.
Ny Folgd., 1892-3, Bd. iv. Lund, 1893.

(10) Wiman, Carl. Ueber Diplograptidae Lapw., and Ueber

Monograptus Geinitz. Bull. Geol. Inst., Univ. Upsala, vol.
i., 1893.

(11) Holm, G. Om Didymograptus, Tetragraptus och Phyllo-

graptus. Aftr. ur Geol. Foren. i. Stockholm Forhdndl.,
1895, translated by Miss Wood and Miss Elles in Geol.
Mag., vol. ii., pp. 433 and 481, 4th Dec.

(12) Hall, James. Graptolites of the Quebec Group, 1865.

(13) Dairon, James. Notes on Graptolites. Trans. Geol. Soc,

Glasgow, p. 176, 1882.

(14) Ruedemann, R. Synopsis of the Mode of Growth and

Development of the Graptolitic genus Diplograptus. Amer.
Journ. Sci., vol. xlix., 3rd ser., p. 453, 1895.

THE GRAPTOLITES. 373

(15) NICHOLSON, H. A., and Marr, J. E. Notes on the Phylogeny

of the Graptolites. Geo/. Mag., 4th Decade, vol. ii., p. 529.

(16) Lapworth, C. The Girvan Succession. Quart. Joum. Geo/.

Soc, vol. xxxviii., p. 537.

(17) Marr and NICHOLSON. On the Stockdale Shales. Quart.

Joum. Geo/. Soc., vol. xliv., p. 654. Also Marr. On the
Wenlock and Ludlow Strata of the Lake District, Geo/. Mag.,
3rd Dec, vol. ix., p. 534, and Notes on the Skiddaw Slates,
ibid., 4th Dec, vol. i., p. 122.

(18) Lake and GROOM. On the Llandovery and Associated

Rocks of the Neighbourhood of Corwen. Quart. Joum.
Geo/. Soc., vol. xlix., p. 426. And P. Lake, On the Denbigh-
shire Series of South Denbighshire, ibid., vol. ii., p. 9.

(19) Watts, W. W. The Geology of the Long Mountain on the

Welsh Borders. Rep. Brit. Assoc., 1890, p. 817, 1891.

(20) TULLBERG, S. A. Skanes Graptoliter. Sver. Geo/. Undersokn.,
_ ser. C, Nos. 50 and 55.

(21) Lapworth, C. Preliminary Report on some Graptolites, etc.

Trans. Roy. Soc. Canada, p. 167, 1886.

(22) HALL, T. S. The Geology of Castlemaine, etc. Trans. Roy.

Soc. Victoria, p. 57, 1895?

(23) Geikie, Sir A. Annual Report of the Geo/ogicai Survey, etc.,

for 1895, p. 27, 1896.

(24) MARR, J. E. On Homotaxis. Proc. Cambridge Phi/. Soc,

vol. vi., pt. ii., p. 74.

J. E. Marr.

INSULAR FLORAS.

PART VI. (b).

IN my article (59) on the flora of the African Islands of
the Indian Ocean, I dealt with the subject in consider-
able detail, but beyond the vascular cryptogams I had very
few data concerning the Isle of Bourbon. Since then
Dr. Cordemoy has published a Flora of the island (60),
which is a consolidation of all the materials he has been
able to collect during the leisure of upwards of thirty years'
residence in the island, though unfortunately without a full
collation with the rich earlier collections in the Paris Her-
barium of Commerson, Du Petit-Thouars, and other botanists.
Moreover, he has not worked out the geography of the
plants to the extent he might have done, so that it takes
some time to find and extract the particulars of special
interest to the geographer. Indigenous and naturalised
plants are included in the same enumeration without any
typographical distinctions ; and the summary is limited to
a table showing the number of species of each natural
order, including naturalised species. A rough calculation
of the number of indigenous species of vascular plants,
described or enumerated, gives a total of about 11 00,
whereof 200 are ferns, and 172 are orchids.' This is nearly
250 higher than Baker's estimate (61) of the vascular plants
of Mauritius; but, although the islands are nearly of the same
size, the mountains of Bourbon rise to altitudes of between
9000 and 10,000 feet, or about 6000 feet above those of
Mauritius ; thus giving an additional climatic zone to the
former island. And an analysis of the components of the
flora shows that Bourbon possesses a much larger temperate
element. But it should be known that Cordemoy takes a
narrower view of species than Baker, especially in ferns ;
and some allowance would have to be made for this in com-
paring the totals. Apart from this divergence, the flora of
the two islands is essentially the same, several genera and
many species being common to both and found nowhere

INSULAR FLORAS. 375

else. The predominating natural orders of vascular plants
occupy nearly the same positions numerically in both islands ;
ferns being first and orchids second, and Leguminosae and
Compositae relatively low down ; very different proportions
from those obtaining in the Madagascar Mora, in which
these four orders occupy reversed positions. Thus : Legu-
minosae, Filices, and Compositae, followed by the Orchideae,
which are represented by just half as many species as the
Leguminosae.

The absence of a number of natural orders from Dr.
Cordemoy's Flora that are represented in Mauritius may
be accounted for partly by the fact that he did not work out
the old collections made before the destruction of the virgin
forests which formerly clothed the island. It is probable
that many species have disappeared from both islands from
the same cause. The following orders known to be, or as
having been, represented in Mauritius are not included by
Cordemoy : Xyridaceae, Scitamineae, Podostemaceae, Myo-
porineae, Bignoniaceae, Lentibulariaceae, Gentianaceae,
Rhizophoreae, Connaraceae, Simarubaceae, Ochnaceae, Bur-
seraceae and Nymphaeaceae. The absence of several of the
foregoing orders might be accounted for without calling in the
theory of destruction, but it would lead too far to attempt the
discussion of the matter here. Myoporum mauritianum is
an instance of a plant, and an order that is no longer repre-
sented, if it ever were ; for there may have been an error
in locality. The only specimen at Kew is labelled as coming
from one small patch at the east end of the island of
Rodriguez, which is some 300 miles distant from Mauritius.
Moreover the Seychelles and Rodriguez between them
possess several natural orders which do not reach Bourbon
or Mauritius, though they are represented in Madagascar.
They are Nepenthaceae, Passifloraceae, Turneraceae, Diptero-
carpeae (?), Ternstrcemiaceae and Dilleniaceae ; whereof the
first and the fourth are essentially Asiatic, the second
and third American, and the two last equally Asiatic
and American. The parasitical Rafflesiaceae are perhaps
the only natural order in Bourbon that is not repre-
sented in Mauritius. Cordemoy records Hydnora afncana

376 SCIENCE PROGRESS.

as common at St. Paul in Bourbon. It inhabits Eastern
tropical and South Africa, though it is not known
from Madagascar or any other of the African islands. Six
or seven species of Hydnora have been described ; all in-
habiting Africa from Abyssinia and Angola southward to
Cape Colony. I have previously noted (62) the discovery of
a member of this order (Cytinus Baroni) in Madagascar.
Since writing that I have seen a third Mexican species.

The intimate relationships of the floras of Bourbon and
Mauritius may be gathered from the presence in the two
islands, and restriction to these islands, of the following
monotypic, mostly very distinct, genera: Cossignya and Dora-
toxylon (Sapindacese), Grangeria (Rosaceae), Roussea (Saxi-
fragaceae), Psiloxylon (Lythracese ?), Fernelia (Rubiacese),
Heterochcenia (Catnpanulacese), Bryodes (Scrophularineae),
Monimia (Monimiaceae) Dictyosperma (Palmae). To these
may be added several other genera of the same geographical
area, represented by more than one species ; in five instances
out of six by three species : Fostidia (Myrtaceae), Pyrostria
and A/y 07itma (Rub'iacedz), Faujasia (Composite), Hyophorbe
and Acanthophcehix (Palmae). Twenty-five other character-
istic genera are restricted to the African region, using that
designation in the sense of including therein the islands
under consideration, Madagascar, and continental Africa.
Trochetia (Sterculiaceae) is remarkable among them as
extending to St. Helena, where it is represented by two
distinct species — or rather was, for one is quite extinct in
a wild state. Psiadia (Composite) has the same range.

Allusion has been made (63) to the phenomenal con-
centration of endemic palms in the Seychelles, and it would
be interesting to give the distribution and affinities of the
palms of the whole of the East African Islands ; but I must-
confine myself to the Bourbon species. The native species
are five in number, namely : Latania Commersonii, Hyophorbe
indica, Dictyosperma album, Acanthophcenix rubra and A.
crinita. All these palms also inhabit Mauritius, and
they are, so far as our present knowledge goes, confined to
the island. All the genera are peculiar to this insular region
if we take in Madagascar, and Dictyosperma and Acan-

INSULAR FLORAS. 377

thophcenix to Mauritius and Bourbon. Latania belongs to
the Borasseae and all the rest to the Arecinese. As stated
before, there is no parallel to this in insular floras of other
parts of the world. Polynesia, both the eastern and western,
is relatively poor in palms, and the West Indian Islands
possess few endemic species ; but, as explained a few pages
back, Lord Howe Island possesses four endemic species
of palms belonging to Australian and endemic genera.

Coming down to species we find that Cordemoy de-
scribes about 200 new ones, which, with those previously
known as endemic, would make probably not less than 25
per cent, of the vascular plants endemic. It is probable
that this number — the number of new species — maybe subject
to some reduction, especially in such groups as the ferns
and grasses in which so many species have a wide range ;
yet 25 per cent, of endemic species is possibly below
rather than above the mark. Nineteen grasses are de-
scribed as new. Considering, however, the general distribu-
tion of grasses, and that only four species are regarded as
endemic in Mauritius, there are good grounds for suspect-
ing that many of the Bourbon species are not really new.

Orchids, epiphytal and terrestrial combined, contribute
no fewer than seventy new species ; and the total number
of orchids thus exceeds the total indigenous species of any
other two natural orders. In Mauritius, orchids are more
numerous than any other order of flowering plants, but
they only occupy the first place by a majority of about ten.
As I have shown elsewhere (64) orchids are exceedingly
rare or entirely wanting in oceanic islands, and such pro-
portions as Cordemoy's enumeration gives would hardly
be found in the richest orchid districts of Asia or America.
Continental tropical Africa, so far as known, is relatively
poor, whilst in Madagascar, according to Baron's tabulation
(65), orchids stand third, being exceeded by Compositae and
Euphorbiaceae. It is true that I have estimated (66) that
orchids are numerically more strongly represented in British
India than any other order of flowering plants, and my
estimate has proved correct in the subsequent elaboration
of this order (67) by Sir Joseph Hooker. It may be in-

378 SCIENCE PROGRESS.

teresting to add that orchids stand third in the flora of the
whole world, and they also take the same position in the
flora of Mexico and Central America.

Returning to the Bourbon orchids ; the regional char-
acteristic AngrcBCum is credited with eighteen new species,
and a total of thirty-two species. There are also new
species of the epiphytal genera Bulbophyllum, Aeranthus,
and Saccolabinm ; but the bulk of the new ones are terres-
trial plants, many of them very rare and inconspicuous, and
most of them of short duration above ground.

On this point Cordemoy says : " J 'en ai moi meme
plusieurs nouvelles, en herbier, que leur mauvais etat de
conservation ne permet pas de decrire. Certainement il
en existe d'autres non encore decouvertes, surtout parmi
les Ophrydees, dont plusieurs parcourent, en quelques
semaines, la periode active de leur vegetation, puis se
replient immediatement, pour passer le reste de l'annee sous
terre a l'etat de tubercule. Plusieurs localites n'ont pas ete
suffisament explorees.'r

Three new genera of this group are described, namely,
Acrostylia, Camilleugenia and Hcmiperis ; the first two
being monotypic and the third having twenty-one species
ascribed to it. All three would be included under Habenaria
by some authors ; but in this extended sense Habenaria is
a vast and heterogeneous agglomeration of species.

Among other genera, of which several new species are
described, I may mention Dombeya, Evodia, Eugenia,
Embelia, Sideroxylon, Geniostoma, Psiadia and Faujasia.

In addition to the new genera of orchids, four others
are proposed, namely, Guya (Bixaceae), Herya (Celas-
tracese), Allocalyx (Scrophulariacese), and Mahya (Labiatae).
According to the author's own admission, three out of
the four are somewhat doubtful, and the affinity of the
fourth is not given more definitely than by placing it in the
tribe Menthese. But Alahya stellata is an interesting plant,
whatever its affinity, because it is believed to be the only
really indigenous member of the Labiatae. It is a dwarf
shrub, very rare, and found only near the summit of the
Grand Benard, at an elevation of about 8650 feet.

INSULAR FLORAS. 379

Strange to say the upper zone of vegetation is less
alpine in character than that of the mountains of Mada-
gascar and Tropical Africa. Cruciferae, Caryophylleae,
Umbelliferae, Primulaceae and Gentianacese, as well as her-
baceous Rosacese and Saxifragaceae, are either exceedingly
rare or entirely absent. In Madagascar, where the highest
point is barely 8500 feet, the following familiar genera
occur : Ajuga, Alckemilla, Cattcalis, Crassula, D?-osera,
Epilobium, Genista, Geranium, Linum, Pimpinella,Sanicula>
Stachys, and Viola, besides many others which are unknown
among the native plants of Bourbon.

Gymnosperms are also unrepresented, both in the indi-
genous vegetation, and among the numerous naturalised
plants. It is the same in Mauritius ; but in Madagascar
one species each of Cycas and Podocarpus has been dis-
covered ; the latter being prominent in certain districts.

Finally, I may add that the following orders are strongly
represented in the Bourbon flora : Malvaceae (Dombeya, 2 1
species, and Ruisia, Astiria, and Trocketia, regional
genera) ; Rutaceae (Evodia) ; Urticaceae (Ficns, and Obetia
and Maillardia, regional genera) ; Euphorbiaceae and Con-
volvulaceae.

Since the untimely death of Dr. H. Baillon another
part (68) of the admirable illustrations of the flora of
Madagascar has appeared. It consists largely of plates
for intercalation, and the highest number is 340. Unfor-
tunately no descriptive or explanatory letter-press has been
published in connection with these plates and none is likely
to be forthcoming. Surgeon-Major H. H. Johnston has
published (69) an enumeration of plants collected by him-
self and regarded by him as indigenous in Mauritius,
though they are not included in Baker's Flora. The
total is fifty species, half of which are cellular crypto-
gams. There is nothing specially remarkable amongst
them. The same gentleman has published an account (70)
of the vegetation of the small islands in the Mahebourg
Bay, Mauritius, namely : He de la Passe, He Vakois, He
aux Fouquets, He aux Fous, He Marianne and Rocher des
Oiseaux. These islands are of coralline limestone forma-

380 SCIENCE PROGRESS.

tion, and their flora is equally as poor, and composed mainly
of the same species as the flora of the small coral islands of
the Pacific Ocean, a specimen of which is given some pages
back.

BIBLIOGRAPHY.

(i) Science Progress, i., pp. 26-35.

(2) J. T. Arundel. The Phoenix Group and other Islands of the

Pacific, 8vo, pp. 8. Reprint from The New Zealand
Herald, 5th and 12th July, 1890.

(3) Report of the Eclipse Expedition to Caroline Island, May,

1883. Memoirs of the National [American] Academy of
Sciences, ii., pp. 1-146, with a number of views, etc. Botany,
pp. 88-90, by W. Trelease, 1884.

(4) C. M. WOODFORD. The Gilbert Islands. Geographical

Journal, vi., pp. 325-350, with a map. Botany, p. 346, 1895.

(5) W. Botting HEMSLEY. The Flora of the Tonga or Friendly

Islands, with Descriptions of and Notes on some New or
Remarkable Plants, partly from the Solomon Islands.
Journal of the Linnean Society, xxx., pp. 158-217, tt. 9-1 1,
1894.

(6) J. J. Lister. The Geology of the Tonga Islands. Quarterly

Journal of the Geological Society, xlvii., pp. 590-617, with
maps and views, 1891.

(7) W. Botting Hemsley. Flora of the Solomon Islands.

Kew Bulletin of Miscellaneous Information, 1 894, pp. 211-
215; 1895, pp. 132-139; 1896, p. 17; and Journ. Linn. Soc,
xxx., pp. 163-165, and 211-217, plates 9-1 1, 1894.

(8) HOOKER'S Icones Plautarum, t. 17 14.

(9) K. SCHUMANN. Die Flora von Kaiser Wilhelms Land, p. 69,

1889.

(10) J. G. BOERLAGE. Handleiding tot de Kennis der Flora van

Nederlandsch Indie, i., p. 445 et p. 673, 1890.

(11) C. Hedley. The Range of Placostylus. Proceedings of the

Linnean Society of New South Wales, ser. 2, vii., pp. 335-
339, 1892.

(12) Science Progress, i., p. 40, 1894.

(13) H. N. Ridley. A Day at Christmas Island. Journal of the

Straits Branch of the Royal Asiatic Society, No. 23, pp. 123-
140, 1891.

(14) H. Trimen. Handbook of the Flora of Ceylon, part ii., Con-

naraceae to Rubiacese, 1894; part iii., Valerianaceae to
Balanophoraceae, 1895.

INSULAR FLORAS. 381

(15) H. Trimen. A Preliminary List of Maldive Plants. Journal

of Botany, pp. 3-6, 1896.

(16) Capt. VV. F. W. Owen. Geography of the Maldiva Islands.

Journ. Roy. Geogr. Society, ii., pp. 81-92, 1832.

(17) Science Progress, i., pp. 387-396.

(18) T. Kirk. Trans, and Proc. N. Zeal. Inst, xxvii., pp. 327-

359, i895-

(19) W. Colenso, H. C. Field, and D. Petrie. Trans, and

Proc. N. Zeal. Inst., xxvii., 1895.

(20) A. Hamilton. Notes on a Visit to Macquarie Island.

Transactions and Proceedings of the New Zealand Institute,
xxvii., pp. 559-579, 1895.

(21) Science Progress, L, p. 395.

(22) Flora of Macquarie Island. Keiv Bulletin, p. 401, 1894.

(23) T. KlRK. On the Flora of Macquarie Island. Report of the

Third Meeting of the Australasian Association for the
Advancement of Science, pp. 226-227, 1891.

(24) T. KlRK. Description of New Grasses from Macquarie Island.

Trans. N. Zeal. Inst., xxvii., p. 353.
(25)1 A. Vollmer. Lord Howe Insel, Pitcairn und Norfolk
Insel. Petermann's Mittheilungen, xli., pp. 72--JJ, 1895.

(26) C. MOORE. Sketch of the Vegetation of Lord Howe Island.

A Report to the Under Secretary for Lands, New South
Wales, 1869.

(27) G. BENTHAM. Flora Australiensis.

F. v. MUELLER. Fragmenta Phytograpihce Australia.

(28) J. B. WILSON. Report to the Colonial Secretary on the Present

State and Future Prospects of Lord Howe Island, 1 vol. 4to.
With Photographs. List of timbers, p. 22. Vegetation by
J. Duff, pp. 28-36, 1882.

(29) ETHERIDGE. Lord Howe Island ; its Zoology, etc., 1889.

(30) F. VON Mueller. Index omnium Insulae Howeanae Plantar-

urn, quas hactenus obtenui, exclusis speciebus certe introduc-
tis. Fragmenta Phytographia Australia, ix., pp. 76-78, 1875.

1 Since my remarks on the flora of Lord Howe Island were put into
type, I have seen the " Macleay Memorial Volume," published by the
Linnean Society of New South Wales, in 1893. It contains a paper by
Prof. R. Tate " On the Geographic Relations of the Floras of Norfolk and
Lord Howe Islands," in which the author arrives at much the same conclu-
sions as myself. I had also overlooked a short article by Mr. C. Moore
{Transactions of the Royal Society of New South Wales, v. (1872), pp. 29-
34), on the same subject, but dealing only with the distribution of the
genera. I may add that my detailed account of the vegetation and flora
of the island has appeared in the Annals of Botany for June, 1896.

382 SCIENCE PROGRESS.

(31) O. Beccari. Malesia, i\, p. 66, 1877.

(32) Science Progress, i., p. 400.

(33) B. L. Robinson and J. M. Greenman. On the Flora of the

Galapagos Islands. American Journal of Science, 1., pp.
135-149, 1895.

(34) W. BOTTING Hemsley. The Flora of the Galapagos Islands.

Nature, lii., p. 623, 1895.

(35) G. Baur. The Galapagos Islands. Proceedings of the Ameri-

can Antiquarian Society, 1891 , and Reprint, 1892 ; and a fuller
account in Bio/ogisches Centralblatt, xii., pp. 221-250.

(36) G. Baur. The Differentiation of Species on the Galapagos

Islands and the Origin of the Group. Biological Lectures
delivered at the Marine Biological Laboratory of Wood's Ho 11,
1894, pp. 67 -7S.
($7) A. Agassiz. General Sketch of the Expedition of the
Albatross. Bulletin of the Museum of Comparative Zoology
at Harvard College, xxiii., pp. 1-89, plates 1-22, including
two maps, 1892.

(38) Botany of the "Challenger" Expedition, \., 1, Introduction, p. 5.

(39) J. D. HOOKER. On the Vegetation of the Galapagos. Trans-

actions of the Linnean Society, xx., pp. 235-262, 1847.

(40) C. Darwin. A Naturalists Voyage, p. 393, edition of 1884.

(41) A Naturalist's Voyage, p. 396.

(42) W. BOTTING Hemsley. Cactacese in the Galapagos Islands.

Nature, liii., p. 31, 1895.

(43) Magazine of Zool. and Bot., i., p. 467, pi. 14, f. 2, 1837.

(44) A Naturalists Voyage, pp. 374 and 382, edition of 1884.

(45) Om Galapagos Oarnes Vegetation. Freg. " Eugenics" Resa.

Bot., p. 95.

(46) Biologischcs Centralblatt, xi., 1892.

(47) J. D. Hooker. Botany of Ellesmere Land and Grinnell

1

Land. Nares's Narrative of a Voyage to the Polar Sea, ii.,
pp. 301-310, 1878.

(48) D. Oliver. List of Flowering Plants in Ellesmere Land and

Grinnell Land, 8o°-83° N. lat. Nares's Narrative of a Voyage
to the Polar Sea during 1875-6, ii., pp. 310-312, 1878.

(49) Science Progress, ii., p. 379, 1895.

(50) A. Trevor-Battye. Icebound on Kolguev. Notes on the

Flora, pp. 396-417, 1895.

(51) H. W. Feilden. Mild Arctic Climates. The Glacialists

Magazine, [., pp. 91-95, 1893.

(52) H. W. Feilden and H. D. Geldart. Notes on a small

Collection of Spitzbergen Plants. Trans. Norf and Norw.
Nat. Soc, vi., pp. 47-53, 1894.

INSULAR FLORAS. 383

(53) F. J. Ruprecht. Flores Samoyedorum Cisuralensium.

Beitrdge zur Pflanzenkunde des Russischen Reiches, zweite
Lieferung, pp. 1-67, tt. 1-6, 1845.

(54) H. MOHN. Einsamkeit Insel. Petermann's Mittheilnngen,

pp. 57-59, 1879.

(55) F. KURTZ. Verzeichniss der auf Island und den Faer Oern

von Dr. Konrad Keilhack gesammelten Pflanzen. Abhand-
lungen des Botaniscken Vereins der Piovinz Brandenburg,
xxxvi., pp. 150-158, 1895.

(56) J. D. Hooker. On the Canarian Flora as compared with the

Maroccan. Hooker and Ball's Journal of a Tour in
Marocco, pp. 404-421, 1878.

(57) H. Christ. La Flore Ancienne Africaine. Archives

des Sciences Physiques et Naturelles, xxviii., pp. 369-374,
1892.

(58) I. Urban. Additamenta ad cognitionem Florae Indiae

Occidentalis. Particula 2. Engler's Botanische Jahrbiicher,
xix., pp. 562-681, 1894-5.

(59) Science Progress, hi., pp. 447-75.

(60) E. Jacob de CORDEMOY. Flore de file de la Reunion, 8vo,

pp. xxvii. and 574, 1895.

(61) J. G. Baker. Flora of Mauritius and the Seychelles, p. 15.*

(62) Science Progress, Hi., p. 457.
(6^) Science Progress, hi., p. 459.

(64) Botany of the Voyage of the " Challenger," i., part i., Introduc-

tion, p. 27, 1885.

(65) Journal of the Linnean Society, xxv., p. 252, 1889.

(66) Biologia Centrali- Americana. Botany, i., p. xv., 1888.

(67) Flora of British India, v., pp. 667-910; vi., pp. 1-198, 1888-90.

(68) H. Baillon. Histoire Naturelle des Plantes de Madagascar.

Atlas, 36e Fascicule, 1895.

(69) H. H. JOHNSTON. Additions to the Flora of Mauritius.

Transactions of the Botanical Society of Edinburgh, 1895.
Reprinted with Additions, pp. 28, 1896.

(70) H. H. JOHNSTON. Report on the Flora of the Outlying

Islands of Mahebourg Bay, Mauritius. Trans. Bot. Soc.
Ediu., 1895. Reprinted with Additions, pp. 36, 1896.

W. BOTTING HEMSLEY.

27

SELECTION IN MAN.

QUESTIONS respecting the origin and development
of race-types have been among the favourite
battle-grounds of anthropologists since anthropology began
to be. Some have held that the countless varieties of type
in man could be accounted for by the simple admixture of
a very few original types, of three for example, a white, a
black and a yellow one, others that nothing was needed to
produce the widest extremes of variation save the direct
influence of what the French call "media" and the
Americans environment. With the development and in-
creasing prevalence of evolutionary theories, the questions
were looked upon from a somewhat different point of view.
The same two parties, however, continued to exist, the one
assigning supreme importance to innate variability controlled
by natural selection, the other to the same variability
controlled by environment. In process of time it became
obvious that there might be other selective agencies than
those commonly understood by the term natural ; and Alfred
Wallace himself pointed out that natural selection must
have been potent in its working on man in the early stages
of civilisation, but that in later stages it ceased to be so,
while other agencies came into play.

Questions dependent on, or arising out of those already

mentioned are innumerable, and in some instances at least

are of obvious and immediate practical importance. For

example : Which are the types of man that are most

suitable for colonisation or acclimatisation in different parts

of the world ? and are they recognisable by colour or

form of head, by kephalic or nasal index, by stature or any

other visible character? What is the connection or relation,

if any, between complexion and liability to malarial fever,

to syphilis, to cancer or leprosy? Are the more fertile

types or strains of mankind to be known by outward signs ?

Are new types of man likely to be developed more suitable

than those now prevailing to the altering conditions of civic

and industrial life, and if so, through what agencies ?

SELECTION IN MAN. 385

Let us begin with the subject of complexion or colour,
because it is one of the most conspicuous differential char-
acteristics of man. The xanthochroic type of Huxley, the
blond, at present so dominant and aggressive, occupying,
in conjunction it is true with the melanochroic (or dark
white), more and more of those parts of the earth, such as
North America, Australia and South Africa, which have
hitherto been the patrimony of the brown or the black man
— is there reason to expect that it will hold its own outside
of its original habitat, or even there ?

The historical evidence is on the surface at least un-
favourable. If we take the words used in their most natural
sense, we must allow that the Greeks and Romans de-
scribed not only the Germans but the Gauls and Thracians
as blond. And they did not mean simply that the blond
complexion was pretty common among these northern
people ; that could hardly have struck them as very re-
markable ; for if they had not had among themselves pretty
frequent examples of it, their descriptions of the four tem-
peraments could hardly be explained.1 Literary portraits,
and personal names such as Flavius, Rufus, Ahenobarbus,
leave no doubt that there was considerable variety of com-
plexion among the Romans of the republican period, though
dark hues may have prevailed ; and it does not appear that
the continual influx of northern blood has been able to do
much, if any, more than to maintain the status in that
respect. The Greeks ascribed yellow locks to Achilles and
Menelaus and other chieftains of the heroic age ; but in the
imperial age the Egyptian limners represented Greek
ladies with black hair and eyes. The ballads of Mount
Rhodope, believed to be of extreme antiquity, and refer-
ring to Philip, Alexander, and even Orpheus, ascribe yellow
hair to their heroes ; but the Pomaks of the Rhodope are
not now a blond race.2 Another argument may be de-
rived from the ancient Egyptian wall-paintings. Not only

1 Among the marks of the sanguine and lymphatic temperaments light
hair is generally mentioned, while black hair belonged to the choleric and
the melancholic. 2 Fligier.

386 SCIENCE PROGRESS.

the Lebo or Tahennu and the Amorites (both probably
enough of North- European origin, though domiciled in
Lybia and Canaan), but some of the Arabian Shashi are
represented as of xanthous complexion. Yet now-a-days
we hear nothing of blonds in the Arabian or Egyptian
populations, except where recent admixture of blood may
be suspected. Again, Flinders Petrie's recent discovery
of the remains of a tall, brown-haired, and apparently
"Aryan" population in Middle Egypt,1 that seems to have
completely and speedily disappeared, reminds us of the
generally accepted statement that the Mamelukes have no
representatives in the Egyptian population at the present
day. On the other hand the alleged blond coloration of
the Guanches in the Canary Islands, and the known fre-
quency of that complexion in the people of the Riff, and in
the Kabyles of some mountainous regions further east,
make it probable that the type of the Tahennu still exists
where climatic conditions are not unfavourable to it. And
after all, these Tahennu may have been only a blond
military aristocracy ruling a melanochroic plebs ; had it
been otherwise, allowing that they had come from the
north, why did they not perpetuate an Aryan language in
North Africa ?

Again, the large xanthous element in the Jews has been
accounted for by the existence of an ancient Amorite cross ;
and on the whole this appears to me the most probable
explanation. We can hardly doubt its antiquity in any
case, since it is present in every section of the Jewish
people, and is very distinct among the Sephardim of the
Levant, though perhaps larger in proportion among the
Ashkenazim,2 whose Gentile neighbours are so largely
blond. In some parts of the Levant, indeed, among the
dark Turks and Armenians, a red beard raises a suspicion
of Hebrew ancestry.

On the whole this kind of evidence, of which much

1 " Indications of the earliest English occupation of Egypt," as
De Lapouge pointedly remarked.

2 Jacobs and Spielmann, Anthrop. Trans. Beddoe, Ethn. Trans.

SELECTION IN MAN. 387

more might be adduced, leads me to think that though
selective agencies in the warm Mediterranean regions are
on the whole adverse to the perpetuation of the blond
type, they are not so everywhere or in very high degree.

Most of what evidence we have from northern countries
makes one doubt whether any change has occurred except
through immigration from melanochroic areas, and con-
sequent admixture of blood. The Icelandic Sagas show
that the Norsemen in the tenth century wTere as diverse in
colour of hair as they are now ; in fact the number of
persons qualified as "black" would be a little surprising, if
one did not allow for the probable inclusion of some whose
hair was really only dark brown. The carefulness of the
descriptions is vouched for by coincidences ; thus, chiefs
with a mixture of Irish blood, such as Skarphedinn and
Kjartan, betray it by some Irish feature. The eyes are
seldom mentioned ; but Egil Skallagrimson, a pure Nor-
wegian, had black eyes.

Similarly the old Irish poems and legends testify to the
occurrence of the same varieties of complexion that now
exist, and particularly to that of the very Irish combination
of blue eyes and black hair, which is ascribed among others
to the famous Diarmaid O'Duibhne, the semi-mythical
ancestor of the Campbells.

Nevertheless I hold to the opinion, though only as an
opinion, not as a firm belief, that the modern Norsemen
are, if anything, more generally blond than their ancestors,
and the modern Irishmen less so. If Scandinavia was, as
now-a-days many think, the officina or breeding-ground of
the blond long-headed type, may not the same agencies
which worked in that direction after the close of the last
glacial period be still operating there now, though it may
be less powerfully ? As for the Irish, it is certainly curious
that no early English writer, so far as I am aware, makes
mention of their dark hair. As I have said elsewhere,
Giraldus tells us that the Welsh were of swarthy com-
plexion, but he says nothing about the colour of the Irish
(though he had much to do with them), except that inci-
dentally and casually he says something about " long

388 SCIENCE PROGRESS.

yellow hair, like the Irish". The Irish colony about Dinas
Mawddwy, in Merioneth, were called "the red men of
Mawddwy". It is probable that the ruling tribes of
Ireland had much more of the blond element than the
servile ones ; 1 and that the former were exhausted by the
long wars with the English, by the military emigrations to
France and Spain, and perhaps the earlier emigrations to
America. Dr. Morton, the first great American anthropo-
logist, in describing the Irish as he saw them, said "eyes
and hair light ". But there is no doubt that, speaking
broadly, there is more dark hair in Ireland than in Eng-
land or Scotland, though there are more dark eyes in
England. The climate of Ireland, cloudy, moist and
temperate, should favour the depigmentation of the eye by
natural selection, and I have pointed out that the English
colonists of Ireland by mixing their blood with that of the
natives have changed their own type more in the direction
of lightness of eye than of darkness of hair.

Mr. Galton has pointed out how rapidly a community
in which the age of marriage is late would, under like
circumstances, be crowded out or superseded by one in
which that age is some years earlier. This consideration
is one of several which account for the rapid extinction of
upper class families in these islands, while the proletariat
multiplies with inconvenient rapidity ; and as the blond
type is more prevalent in the upper than in the lower classes,
it also is probably in process of diminution. If, however,
it can be shown that the blond is more subject, in this
country, to diseases of such a nature as to shorten life, and
reduce the duration of the period of child-bearing and child-
begetting, this same result would follow. Now there is a
good deal of evidence as to the greater liability of blonds
to certain classes of disease (in America at least), in
Baxter's great work on the medical statistics of the Civil
War. There are certain possible fallacies which may
underlie Baxter's figures, to some of which De Candolle

1 Thus MacFirbis, in a well-known passage, describes the Tuatha De
Danaan as fair, and the Milesians as "white of skin, brown of hair," but
the Firbolgs as a servile race, and black-haired.

SELECTION IN MAN. 389

has directed attention ; but if we assume that the con-
clusions which result from them are at all approximately
Correct, it follows that the blonds in America have less
chance than the brunets of contributing their due propor-
tion to the next generation. Under these conditions the
blonds ought to diminish relatively, and the brunets to
increase ; and accordingly we find that of accepted soldiers
there were among the white natives of the United States
about (per cent.)

66 light and 34 dark complexioned, but
among the English 70 ,, 30 ,,

Irish 70 „ 30

„ Germans 69 ,, 29 „

Thus the men of American birth yielded a larger pro-
portion of brunets than those of any of the nations that
had most largely contributed to their ancestry, which is
nearly equivalent to saying that the Americans are more
generally dark complexioned than their ancestors were.
Gould (quoted by Ripley) found that the natives of the
eastern states were also darker than those of the west.
But whether this last fact is occasioned by the parentage
of the western men being more directly European, or
whether it is connected with the more migratory character
of the blond type, must be left for the present undeter-
mined.

Of European evidence on the relation of complexion
and disease there is, so far as I am aware, no great amount.
My own observations have shown that it is a mistake to
suppose, as many do, that light-haired persons are in
England more liable to phthisis than others. I have also
pointed out that cancer is more common in persons of dark
complexion, and in this I am supported by the observations
of Dr. Roger Williams. This last fact has, however, very
little bearing on the subject in hand, for as cancerous disease
usually attacks persons who are beyond the child-producing
age it can have very little effect on the proportions of the
different complexions of the next generation.

As we possess for France not only elaborate recruiting
statistics, with numerical lists for the principal disqualifying

390 SCIENCE PROGRESS.

diseases, but also Topinard's departmental statistics of
colour, and Collignon's of head-breadth, and Bertillon's
of mortality, one ought, it would seem, to acquire therefrom
some solid grounds for the connection of physical types with
disease, and for the estimation of their comparative liability,
and of the probable results in the direction of selective pro-
pagation. In reality this turns out to be extremely difficult.
"The prime difficulty" in such questions "is that these
two factors, material prosperity and ethnic intermixture,
in most cases follow the same laws of geographical dis-
tribution."1

Thus in France the conquering races, in most of which
blond types originally prevailed, occupied, as a rule, the
most fertile tracts, which were also generally the most level
and those contiguous to the great ways of communication.
It is in such tracts that civilisation usually progresses fastest,
that great cities arise with their vices and sanitary disad-
vantages, and that blood is most mixed by continual
migration and marriage. All these circumstances and
conditions have to be taken into account before we can
undertake to say anything as to the correlation of physical
type with disease or military aptitude. The most promising
plan seemed to me to be the throwing together of a number
of departments having all one common character, but other-
wise differing variously. The results thus gained are,
however, more curious than conclusive. French anthro-
pologists generally describe the tall, blond, long-headed
type as subject to dental caries and myopia, and some add
hernia to the list of its defects. Now the six departments,
Nord, Pas-de-Calais, Somme, Aisne, Oise, and Calvados,
which seem most distinctly to combine in their population
all three marks of this type, have indeed a very bad record
for dental caries, and, except Calvados, for general military
unfitness ; but three out of the six stand much better than
the average of France as regards myopia and hernia. More-
over, bad teeth in the departments of France, strangely
enough, usually co-exist with a low mortality, and I am

1 Ripley, "Ethnic Influences in Vital Statistics," Q. P. American
Statistical Association.

SELECTION IN MAN. 391

disposed to think that both are the outcome of some
influences which increase in potency with the advance of
civilisation. In any case the frequency of dental caries
does not seem to have an unfavourable selective influence.

Phthisis, however, may and does have such an influence.
And Houze, having shown that it is more prevalent among
the taller and fairer Flemings than among the shorter and
darker Walloons, concludes that it has been the principal
agent in producing the supposed reduction of the blond
type in Belgium and elsewhere.

Now in England, as I have already stated, the propor-
tion of blonds in the general population is quite as great as
among the subjects of phthisis, but that of tall men among
the phthisical is greater than that of short men. Let us see
how it is in France.

"Pulmonary disease," "scrofula" and weak "constitu-
tion ' seem to be so often confounded or interchanged in
the recruiting statistics, that I have thought it advisable to
class the three together, with the following results.

The three together are, or rather were in Boudin's
time, the cause of rejection of conscripts in about the follow-
ing order : — 1

49 in France.

42 ,, 10 most blond departments.

39 ,, 10 most brunet.

41 ,, 10 departments with tallest population.

44 ,, 10 ,, ,, shortest ,,

54 ,, 6 ,, ,, combination of stature,

blond complexion and long head.
48 ,, 5 departments with combination of stature,

blond complexion and long head,
excluding the Nord.

1 This is not the correct way of putting it ; but we have here the result
of averaging the ranks in each of the three classes of disqualification, and
counting each of equal value. In reality the number rejected for weak-
ness of constitution is vastly greater than that for scrofula, and that again
than for phthisis.

The low position of France as compared with her components is due
to the greater and denser population of some of the vvorst departments,
such as Seine and Nord.

43 in 10

43

, 10

43

, 10

52

• 5

49

- 5

22 ,

- 4

45

. 9

37

1 U

392 SCIENCE PROGRESS.

in 10 departments most long headed.

,, most mountainous.

,, most level but thinly peopled.

,, most urban.

,, Normandy.

,, Brittany.

,, with population of Auvergnat type.
„ ,, ,, ,, Remolothringian

type-
Unquestionably the northern blond type does show badly
here, but whether the blond complexion is much in fault
is doubtful. The Remolothringian region (= Austrasia,
or Champagne and Lorraine), which is one of the most
blond areas in France, but brachykephalic, stands extremely
well ; in Brittany the Morbihan, the most blond depart-
ment, stands best, and in Normandy the Orne, the least
blond, stands worst.

The low position of the Nord may be compared with
that of the ethnologically similar or almost identical Flemish
zone of Belgium. Houze himself ascribes this partly, but
not, I think, wholly, to poverty, crowding, sedentary
occupation, in fact to a number of causes outside of
race.

Another method of inquiry suggests itself. If it be
true that the blond type is more susceptible than the
brown to the malign influences of urban life, and especially
to phthisis, which is largely a disease of crowded city-
dwellers, we should find this type less frequent proportionally
than the brown in ancient cities. On this point we have a
great deal of evidence; the greater part of this is supplied by
the great inquest of Virchow into the colours of the school-
children of Germany, those of Schimmer in Austria, of
Kollmann in Switzerland, and of Vanderkindere in Belgium :
we have also the observations on adults in Italy of Livi,
and those of myself in the British Isles.

Georg Mayr, analysing the returns for Bavaria,
pointed out that the town populations had on the whole a
larger proportion of dark eyes, hair, and complexions than

SELECTION IN MAN. 393

the rural districts, and it appeared to him that this excess
could not be accounted for by the larger proportion of Jews
in the towns, as it occurred, though perhaps to a less extent,
in places where the Jews were few.1

The subject has not been so carefully worked out for other
parts of Germany ; but a cursory examination of Virchow's
figures shows that there is a larger proportion of dark hair
in most of the great cities than in the surrounding rural
districts, and this is more decidedly the case with the pro-
portion of brown compared to blue eyes. Of 32 urban
communities I find that in

1 1 the proportion of dark hair to fair is greater, and that of brown

eyes to blue much greater than in the surrounding districts.
4 — of dark hair greater, of brown eyes greater.
4 — of dark hair greater, of brown eyes greater in less degree.
2 — of dark hair equal, of brown eyes greater.
2 — of dark hair less, of brown eyes greater.

4 — of dark hair about equal, of brown eyes about equal.

5 — of dark hair less, of brown eyes less.

These last are Halle, Wiesbaden, Krefeld, Ulm and
Metz, most of which are towns which have grown rapidly
of late. In the case of Metz the recent additions to the
population have been derived from the blond region of
Northern Germany. It may be noted that it is in that same
blond region, generally speaking, that the most marked
examples of the rule just laid down occur,2 which fact
strengthens the suspicion that the phenomena are largely
due to the fact that the populations of these cities are
partly constituted by immigrants of dark complexion from
southern countries, including the Jews.

In Schimmer's Austrian statistics this last source of
difficulty is avoided, the Jews being returned and classified
separately from the Gentiles. Of 30 cities separately re-
turned, 1 5 show a larger percentage of dark hair than their
surrounding districts, and 14 a smaller one; in the remain-

1 Thus it does appear in non-Semitic Nurnburg, though it is much
more distinct in Semitic Furth.

2 E.g., Minister, Hanover, Altona, Berlin, Posen, Danzig, Elbing,
Kbnigsburg.

394 SCIENCE PROGRESS.

ing one, Linz, the proportions are identical. So far, then,
there is blank disappointment ; but when the eyes are
examined the case is quite different : 27 cities show a larger
proportion of dark eyes than their environs, and 3 only a
less proportion.1 In several of these 27 cases questions of
race at once suggest themselves. In the Czechs, as in the
Irish, the combination of light eyes with dark hair is
common, while it is rare among the Germans. When,
therefore, we find that in all the 6 cities of Moravia
German is the school language, while in the country
districts it is either Slavonic or mixed, and that in every
one of these cities the eyes are darker and the hair lighter
than in the surrounding districts, we need go no further for
an explanation. But this will not serve in all the cases ;
and some probability remains that there is a certain kind of
selection at work to darken the eyes of the urban popula-
tion.

In Belgium the case is not so clear. Ghent, Antwerp,
Ostend, and Verviers come out much darker than their
neighbours ; in most other cases the differences are slight
either way. The cantons in Belgium are generally large,
so that it is difficult to separate the urban and the rural popu-
lations. I have however picked out 1 1 cantons in which I
think the urban element most greatly preponderates, and the
results are as follows.

Of the 11,9 have a larger percentage of dark eyes than
the arrondissements to which they belong, 1 of lighter eyes ;
and in one, Mechlin, there is equality. But the hair, as in
Austrian schedules, comes out about equal ; in 6 of the
towns it is darker ; in 5, including Brussels and Liege, it is
lighter. Ghent is, I suppose, the city in which the unfavour-
able selective influences of urban life (overcrowding, poverty,
sedentary occupation, infectious disease, etc.) are likely to
have been most intense.

In Switzerland Dr. Kollmann's schedules yield only two
instances of a nearly pure urban community, Basel and

1 Dozen, Bielitz, and Czernowitz (in the Bukowina) : they are all
comparatively small places, and all near to race frontiers, which may
possibly account for the anomaly.

SELECTION IN MAN. 395

Geneva. Each of them is on a frontier, each is a singularly
favourable specimen of a city, and is of little service for our
purpose. Both Basel and Geneva have almost certainly a
more blond population than that which surrounds them,
whether Swiss, French, or German.

In the West of England, according to my own published
observations on 3630 adults, mostly hospital patients, of
whom 2486 were natives of towns, and 1144 of rural
districts, the proportion of dark hair in towns was to that
in the country, reckoning by the index of nigrescence, as
31 to 35 ; but that of dark eyes was as 58 to 49. We have
here nearly the same phenomena as those we found to be
so common in Germany, Austria, and Belgium.

In the British Isles generally, the drift of my own very
extensive local observations (in which the place of birth
however was never actually ascertained) was to show that
in large towns, especially those with an old settled popula-
tion, the darker colours both of hair and eyes were more
prevalent than in the surrounding districts. This applied
to the greater part of Britain, but in parts of the west where
the native population is generally dark-haired, e.g., Shrews-
bury and Truro, the proportions may be reversed. The
British military statistics, so far as investigated, viz., to the
number of 13,800 deserters, yield results similar, but not
strongly marked. Thus London, Birmingham, Bristol,
Newcastle, Brighton, and Portsmouth give an index of
nigrescence of 8, against one of 4*9 for the rest of England ;
the proportion of dark eyes for the towns named being 39*5
per cent., but for the rest of England, 387. Edinburgh
and Glasgow give together an index of 1 1 '8, the rest of
Scotland of 0*3 only, the percentages of dark eyes being 29
and 27*8 ; and Belfast and Dublin give an index of 187
against 15*2 in Ulster and Leinster, with percentages of
dark eyes amounting to 32 and 28*4. The figures might
be dissected with advantage, but to do so would lengthen
this paper inordinately.

Livi's statistics as to this point are perhaps the most
interesting, and have the advantage of beino- founded on
the physical characters of adolescents (i.e., conscripts). He

396 SCIENCE PROGRESS.

finds that fair hair is more uncommon and dark eyes are
more frequent among the inhabitants of cities and their
immediate vicinity than among those of the surrounding-
country. And this applies more or less to the whole of
Italy, and cannot, therefore, apparently be accounted for
by the immigration of the dark type from southern Italy
into the northern cities, where the blond type is more
common than in the south.

Thus I find in the northern and more blond region
(Piedmont, Lombardo-Venetia, Liguria) 17 urban popula-
tions which, on a balance of eyes and hair, are darker than
the rural populations around ; 3 which are lighter, Brescia,
Como, Rovigo ; and r, Verona, where the conditions are
equal. In the central provinces, from Emilia to Campania
inclusive, 19 cities are darker, 9 are lighter, and 2 are equal.
In the south, including Apulia, etc., and the islands, where
blonds form a very small minority, 1 1 cities are darker and
5 lighter. Thus in the north the rule obtains in 82 per
cent, in the centre in 63, in the south in 69. The greater
darkness appears to affect the eyes and the hair with
something like equality, though not uniformly.

Livi, finding that the blond complexion is, with identity
or supposed identity of race, more prevalent in the poverty-
stricken mountainous districts than in the plains, and putting
that fact into connection with its less prevalence in the
cities, is disposed to consider it as connected with poor
food and hard labour, which may retard development of
pigment ; in fact, he thinks the deposition of pigment to be
an index of force and of development. Of course this is as
yet unproven, and there is much to be said for and against
the doctrine. But it does seem that we have evidence
enough to show that in a great part of Europe the citizens
are darker than the peasantry. This may be due to some
direct influence of urban life, such as deficient oxygenation
of the blood in children, but that seems very improbable.
More probably it is due either to some kind of social
selection such as Ammon and De Lapouge have studied,
or else to the selection of the fittest for town life by the
destructive agency of conditions more unfavourable to the

SELECTION IN MAN. 397

blond than to the brunet child. I propose to follow out
the subject further in another article.

BIBLIOGRAPHY.

Baxter. Medical Statistics of the Provost- Marshal-General 's

Bureau. Washington, 1875.
BEDDOE. Races of Britain, 1885. Test, of Local Phen. in IV. of

England to Permanence of Anth. Type. Anth. Me?n., vol. ii.
HouzE". La Taille, etc. Bruxelles, 1888.

KOLLMANN. Statist. Erheb. u. d. Farbe der Augen, etc. 1881.
BOUDIN. Geographie Medicate. Paris, 1857.
Livi. Antropometria Militare. Roma, 1896.
SCHIMMER. Erheb. u. d. Farbe der Augen, etc. Oesterreichs, Wien,

1884.
VANDERKINDERE. Nouvelle [Recherches sur V Ethnologie de la

Belgique. Brux., 1879.
VlRCHOW. Gesammtbericht . . . uber die Farbe, etc., der

Schulkinder in Deutschland. Archiv f Anthr. 1886.
GEORG Mayr. Die Bayerische fugend. 1875.

John Beddoe.

RECENT DISCOVERIES IN AVIAN
PALAEONTOLOGY.

FOR reasons long ago pointed out by Lyell, fossil
remains of birds are much more rarely found than
those of other vertebrates, and, as a rule, occur in a very
fragmentary condition. These circumstances, coupled with
the difficulty in arriving at accurate determinations, owing
to the great general similarity in the skeletal structures in
most of the members of the class, have a direct bearing
upon the scantiness of the results that have been attained
in avian palaeontology. In spite of these drawbacks, how-
ever, some not inconsiderable additions to our knowledge
of fossil birds have been made during the last two or three
years, and a short account of the chief papers on this subject
may be of some interest. It will be convenient to take the
papers roughly in the order of the geological age of the
fossils they treat of, and to commence with those relating to
the most ancient types.

Pre-tertiary Birds. — Unfortunately, with one exception,
no remains of pre-tertiary birds have been discovered during
the last few years. This is the more to be regretted because,
interesting though many of the tertiary birds may be, they
are in all essential respects similar to recent forms, and
throw no light whatever on the mystery of the origin and
early history of the group, the key to which lies buried in
the Jurassic and Cretaceous rocks.

The single exception referred to is an imperfect tibia
obtained at Judith River, Montana, from Cretaceous
deposits of somewhat later date than those which formerly
yielded the remains of Hesperornis and Ichthyornis. This
tibia has been described by Marsh (i), who regards it as
indicating a bird about two-thirds the size of Hesperornis,
to which it is closely related, and has made it the type
of a new genus, Coniornis, its specific name being C. alius.

Tertiary Birds. — In tertiary deposits of various ages
and in widely distant localities, some important discoveries
of bird remains have been made of late.

DISCOVERIES IN AVIAN PALAEONTOLOGY. 399

From the Eocene of New Jersey Marsh (2) has described
some fragmentary bones which he considers belonged to a
large struthious bird, Barornis, related to Gastornis and
Diatryma from the Eocene of Europe and North America
respectively. The specimens seem, however, to be too im-
perfect to admit of complete certainty as to the affinities of
this bird, but it may be remarked that the " struthious "
nature of Gastornis is very doubtful, though it was pro-
bably " ratite ': in the morphological sense of that much
abused term.

A portion of a metatarsus obtained in Vancouver Island
from a deposit of Eocene or, at latest, Oligocene age, forms
the subject of a memoir by Cope (3). This author, after
an exhaustive comparison with recent types, comes to the
conclusion that its affinities lie in the direction of the
Steganopodes, and that of these Pelecanus is the nearest
ally of the extinct form, to which the name Cyphornis
magnus has been given. The presence of a large pneumatic
foramen on the anterior face of the bone is strongly in favour
of this view, and if, like the Pelicans, Cyphornis was
capable of flight, it is by far the largest flying bird hitherto
recorded.

A most important addition to our knowledge of the
avi-fauna of the earlier tertiary rocks of Europe has recently
been made by Professor Milne Edwards, to whom students
of this branch of palaeontology are already more deeply
indebted than to any other writer. In a paper (4) read at
the Ornithological Congress at Buda Pesth, he described a
number of bird remains from the well-known deposits of
phosphate of lime (Phosphorites) which occur in the neigh-
bourhood of Caylus (Lot) in Southern France. The mam-
malian fauna of these deposits, described by Filhol and
others, is an extremely rich one, and Lydekker has shown
that several characteristic members of it occur at Hordwell
in Hampshire in strata of Oligocene (Up. Eocene) age.

The birds now described belong to some seventeen
genera, of which ten are new ; these include representatives
of several sub-orders. Only the more interesting of the
new forms need be noticed here.

28

4oo SCIENCE PROGRESS.

Of these perhaps the most important is Archczotrogon,
which is closely related to the Trogons, and may indeed be
an ancestral form of the genus Trogon, an extinct species
of which has been recorded from the Miocene of Allier.
At the present day these birds occur in the Neotropical,
Ethiopian, and Indian regions ; and it is remarkable that
the extinct Miocene bird of Southern France should belong
to a Neotropical genus rather than to one of those found in
the Old World. This peculiar distribution of the recent
and fossil forms is shown in a still more marked manner
in the case of the next genus, Filholornis, which is said
to be closely allied to Opisthocomns. The only known
representative of this genus is the Hoatzin (Opisthocomus
cristatus), which is one of the most peculiar and isolated
forms of Carinate birds now living. It occurs only in
Guiana and the Amazonian region, and is referred to a
separate sub-order of which it is the only member. It is
usually regarded as a primitive type, and the occurrence
in Europe of a closely related bird is, therefore, another of
those numerous cases in which such generalised types, now
found only in the Southern hemisphere, have extinct re-
presentatives in the Northern. That the determination of
the affinities of Filholornis is correct there seems to be no
doubt, since Milne Edwards states that its ulna is almost a
facsimile of that of the Hoatzin, in which that bone is of a
peculiar and distinctive form.

In the same memoir several new ralline birds are added
to the already numerous rails recorded from the Tertiaries
of France. One of the new forms, Rallus dasypus, though
much smaller, is said to resemble Ocydromus in the form of
its humerus ; and another, Elaphrocnemus, a new generic
type, approaches Aphanapteryx in the structure of its meta-
tarsus. The occurrence in the lower Tertiary deposits of
Europe of a large number of rails seems to be rather a
strong argument in favour of a northern origin of the group,
which, as Milne Edwards points out, is an extremely ancient
one, of which at the present day we are only acquainted with
some more or less degenerate descendants. Many of the
more modified forms, such as Ocydromus and Aphanapteryx,

DISCOVERIES IN AVIAN PALAEONTOLOGY. 401

are now confined to, or have recently become extinct in, the
Southern hemisphere. Between these and the primitive
generalised rails there must have been many intermediate
forms, one of which, in the opinion of Milne Edwards, is to
be found in this new genus, Eldphrocnemus.

Other new genera of which the affinities are more doubt-
ful are Orthocnemns, which resembles the Storks and Bus-
tards in some respects and the Rails in others, and Tapinopus,
which seems to have been a short-legged wading bird. We
may also notice Necrobyas, a genus of owls presenting a
combination of characters not found in any recent form ;
TacJiyornis hirundo (previously described by Lydekker as
Aigialornis gallicus), which is referred to the Cypselidce ;
Dynamopterus velox, a cuckoo closely resembling Eudynamis
orientalis, an inhabitant of the Austro-Malayan region ;
Geranopterus, allied to the Rollers and Momots ; and,
lastly, Pterocles vatidus, a sand-grouse considerably larger
than any recent species.

Although many of the genera and species above noticed
are founded on single or, at best, a very few bones, still in
the hands of one so experienced in avian osteology as
Professor Milne Edwards such material is sufficient for
a fairly certain determination of the affinities of the fossil
forms ; and in this case the importance of the results from
the point of view of geographical distribution cannot easily
be over-estimated. It is much to be regretted that this
valuable paper is not illustrated, since even the most careful
descriptions of bird bones are very unsatisfactory without
fio-ures.

From the Middle Miocene of La Grive-St.-Alban in
South-Eastern France, Lydekker (5) has described a
small collection of bird bones. These, which do not in-
clude any very striking novelties, are referred to a new
species of Owl, a large Pheasant, previously recorded by
Milne Edwards from beds of about the same age at
Sansan, a number of quail-like birds {Palcsortyx\ a Sand-
piper and an undetermined Picarian bird.

The next addition to the ranks of fossil birds to be
considered is by far the most important that has been

4o2 SCIENCE PROGRESS.

made since Marsh's discovery of the Toothed birds of
North America. In this case Patagonia, a region long
known for the wealth and peculiar character of its fossil
Mammalia, has yielded a number of the most extraordinary
avian types yet known. The discovery of these is due
to Dr. F. Ameghino and his brother, to the former of
whom we are indebted for the most complete account of
them that has yet been published.

The first mention of the existence of gigantic extinct
birds in Patagonia occurs in a letter from Carlos Ameghino,
published in the Revista Argentina de Histoida Natural,
April, 1 89 1, and containing a report of the results of his
collecting expedition in Patagonia.

Some years before this (in 1887) F. Ameghino (6) had
described under the name Phororhacos longissimus the
symphysial portion of a large mandible which he considered
to belong to an edentate mammal ; a portion of a cranium,
the type of the genus Tolmodzts, was also referred to
a member of the same class. In 1891, however, thanks to
the new and better material obtained by his brother, he
was able to show clearly (7) that both these specimens were
in fact portions of the skeletons of gigantic birds, and to
give a fairly complete diagnosis of the genus Phororhacos.
In some points, as for instance in the statement that teeth were
present, and that there was a bony helmet-like crest on the
skull, this diagnosis, as Ameghino himself afterwards showed,
is not quite correct; but it was the first definite statement
of the chief characters of these extinct birds. The mandible
was shown to be of enormous size and to curve upwards
at its anterior end in a manner almost unique among birds ;
for though Psophia and Dicholophus were compared with
it in this respect, they do not in fact possess this character.
The upper mandible forms a strong hooked beak like that
of a raptorial bird.

In the same year ( 1S91) Moreno and Mercerat pub-
lished a catalogue of the fossil bird remains in the La
Plata Museum (8). This was illustrated by a large series
of very beautiful photographic plates, but unfortunately
these were unaccompanied by any adequate description of

DISCOVERIES IN AVIAN PALAEONTOLOGY. 403

the specimens. Several extinct penguins of the genus
Palceospheniscus, from so-called Oligocene beds, as well as
a number of Pleistocene bird remains, were figured in this
work, but by far the most important section is that dealing
with the great flightless birds of the Santa Cruz Beds.
For the reception of these the authors established a new
order, the Stereornithes, which was subdivided into four
families, the Brontomithidae (including the genera Bron-
tornis and Rostromis), the Stereornithidce (with Phororhacos,
Stereornis Mesembryornis and Patagomis), the Dryor-
nitkidce (with Dryornis) and the Darwinoriiithidce (with
Darwinornis and Oweniornis). Psilopterus (a name which,
being preoccupied, was afterwards changed by Ameghino
to Pelecyornis), a genus probably related to Phororhacos,
was placed in the Cathartidce.

At the end of the same year Ameghino published a
synopsis of the South American fossil birds (9) in which
he severely criticised the classification given above. He
asserts that nearly all the new genera are merely synonyms
of Phororhacos ; the only exceptions being Brontornis
which includes Rostromis, and Psilopterus {Pelecyornis)
which embraces Patapornis. Examination of the figures
given by Moreno and Mercerat shows that in many
cases, at least, he is right ; for instance Ste?'eomis is
clearly the same as Phororhacos. On the other hand
Dryornis, the sole member of the Dry omit hidce, is founded
on the distal end of a humerus, which, judging from the
figure, is probably that of a large vulture, most likely the
Condor ; it may be pointed out that this specimen is not
from the Santa Cruz Beds but from a Pleistocene de-
posit.

In this paper Ameghino himself refers all these flightless
birds to two families, the Pelecyornithidce (including Pele-
cyornis and two new genera, LopJiiornis and Anissolomis)
and the Phororhacosidce (with Brontornis, Phororhacos, and
a new genus, Opisthodactylus). All these he regards as
Ratitce, and in this he was followed by Gadow (10) and
Lydekker (11). Subsequently the latter of these writers,
relying on the fact that the quadrate in Phororhacos pos-

404 SCIENCE PROGRESS.

sesses a double head for articulation with the skull, changed
his opinion, and now considers them as degenerate Carinatse
in which the wing has been reduced in size.

Till recently our knowledge of the Stereornithes depended
almost entirely on the preliminary notices of Ameghino,
and on the plates of the catalogue of Moreno and Merce-
rat. At the beginning of last year however the former
author published by far the most important contribution
(12) to this subject that has yet appeared. He now de-
scribed not only the specimens to which his preliminary
notices referred, but also a large number of additional
remains. The classification followed in this paper is dif-
ferent from that in his " Enumeracion," the order Stereor-
nithes being adopted and subdivided into two families, the
Phororhacidcz and Opisthodactylidce. In the former Pele-
cyornis and Lophior'nis are now included, while Anissolornis
is considered to be a Gallinaceous bird : several new genera,
some of which appear to be of rather doubtful validity,
are also added. The Opisthodactylidce include one genus
only, Opisthodactyhis.

Of the Phororhacidcz the skeleton of Pkororkacos injlatus
is by far the most completely known, the skull, mandible,
pelvis, the bones of the fore and hind limb, and some
vertebrae being described and figured. The skull is of
a very remarkable appearance ; from the side it most
resembles that of a Raptorial bird, the enormous beak
being sharply hooked at the anterior extremity, but when
looked at from above it is seen to be much compressed,
so that the premaxillary region, though very deep from
above downwards, is extremely narrow from side to side.
The quadrate has a double head for articulation with the
skull, a character which, as Lydekker has pointed out (13),
is opposed to the inclusion of these birds in the Ratitce.
The mandible is very heavily built, and its anterior end is
curved upwards in a manner very unlike the ordinary avian
mandible. The sternum is, unfortunately, quite unknown,
but the coracoid and scapula have been preserved. The
former is long and slender, quite unlike that of any Ratite
bird ; the acro-coracoid process is almost entirely wanting, and

DISCOVERIES IN AVIAN PALAEONTOLOGY. 405

the only avian coracoid which at all resembles the fossil in the
form of its upper end is, I believe, that of Aptornis. The
wing-bones are very small in proportion to the size of the
bird, but, at the same time, are stout and strong ; the ulna
bears a number of tubercles marking the points of insertion
of the secondaries. The pelvis is long and narrow, but in
the posterior half, at any rate, it has been somewhat crushed,
so that in fact it is broader than would appear from Ame-
ghino's figure. The hind limb is long and comparatively
slender ; in the tibia there was a bony extensor bridge, and
in the metatarsus the hypotarsus is simple. All the above
details are taken from the skeleton of a single individual of
the smaller species, Phororhacos inflatus, in which the skull
is about thirteen inches long. In these birds the head is
proportionately very large, and this species probably only
stood about three feet high at the middle of the back.
Phororhacos longissimus is about twice as large, the skull
being two feet long and about ten inches high. Of the
other genera Pelecyomis is the best defined, the pelvis and
most of the limb bones being known. As already mentioned
this genus was placed by Moreno and Mercerat among the
Cat hart idee : and though there is little doubt that this is
incorrect, it is by no means clear that Ameghino is justified
in placing it in the Phororhacidce, the pelvis being strikingly
different from that of Phororhacos and the wing proportion-
ately so much larger that it was probably still efficient as an
organ of flight. The other genera of the family are for the
most part known only from mere fragments of limb bones.
Brontornis is a much larger and more heavily built bird than
the largest species of Phororhacos, and Opisthodactylus is
chiefly remarkable for the peculiar position in which Ame-
ghino supposes the hind toe to have articulated with the tarso-
metatarsus. In this paper also several extinct Penguins
are described, as well as a number of ordinary Carinate
birds belonging to several families.

Lydekker points out (14) that the age of the deposits in
which these avian remains are found is probably much over-
estimated by the South American writers, and that they are
probably Miocene. He also discusses the relationship be-

4o6 SCIENCE PROGRESS.

tween the Gastornithidce of the Eocene of Europe and the
Stereomithes to which that family has been referred, and
concludes that though it is not impossible that some affinity
between them may exist, its nature is quite uncertain.

In a notice of the same memoir (15) the present writer
has compared the skeleton of Phororhacos with several
other types, and a considerable degree of resemblance with
the Cariama (Dickolop/ms) was found to exist, particularly
in the structure of the metatarsus. If further investigation
of the specimens themselves should confirm these observa-
tions, the Cariama would appear to be related to these
gigantic and highly specialised extinct birds somewhat as
the recent Armadillos are to the extinct Glyptodonts. In
both cases the recent forms cannot be regarded as direct
descendants of the fossil giants, but rather as more gene-
ralised descendants from the same common stock, which
have escaped extinction both on account of their smaller
size, and more particularly, because being less specialised
they were less affected by changes in the conditions of life.

The specimens described by Ameghino have been pur-
chased by the Trustees of the British Museum, and many
of them may now be seen at the Natural History Museum.

No papers of importance dealing with upper tertiary
birds have appeared within the time to which this review-
is limited.

Quaternary Birds. — During the last three years some
important additions to our knowledge of the extinct stru-
thious birds of Madagascar, the sEpyornitJiida!, have been
made. Until 1893 only the bones of the hind limb and
some imperfect vertebrae of these birds were known, and
no paper describing new material had appeared since the
publication of Milne Edwards and Grandidier's classical
memoir in 1870. In 1893 Burckhardt (16) gave a very
detailed account of a small collection of /Epyornis remains
that had been obtained at Sirabe. in Central Madagascar.
This included not only limb bones and vertebrae, but also
the greater part of the pelvis and sacrum ; all the specimens
were referred to a new species, JE. Hildebrandti, which the
author compares with those previously known and with the

DISCOVERIES IN AVIAN PALEONTOLOGY. 407

other RatitcE. The conclusions he arrives at are of con-
siderable interest. Milne Edwards and Grandidier expressed
an opinion that JEpyornis is related to the Dinornit hides,
coming between that family and the Australasian Ratites,
Casuarius and Dromceus, the latter of which according to
some writers is the most primitive of the group. Burck-
hardt also considers that JEpyornis is most closely related
to Casuarius and Dromczus, but believes that the resem-
blances between it and Dinomis are merely the result of
parallelism in evolution, the skeleton in both cases having
become extremely massive. On the other hand, he believes
that in some of the characters of the pelvis and other parts
of the skeleton, and also in the structure of the egg-shell,
jEpyornis approaches Struthio, and suggests that from the
primitive Dromczus-Casuarius stock the Dinornithidce and
Apteryx were descended on the east, while towards the
west a branch arose which split up into the /Epyornithidce
and Strut hionidcz. This view, though it may perhaps ap-
pear to be supported by the geographical distribution of the
families concerned, cannot be regarded as established. The
structure of the skull and shoulder-oirdle and sternum when
known will probably settle this question.

At the beginning of 1894 the present writer described
{17, 18) a species of yEpyornis, /E. Titan, far larger than
any then known. The tibia is about thirty-one inches long,
enormously massive, even more so than that of Pachyornis
elephantopus. In January of the same year Milne Edwards
and Grandidier (19) published a preliminary notice of a very
large collection of AEpyornis remains. They name some four
or five new species of sEpyornis, and establish a new genus,
Mullerornis, for the reception of three smaller forms of
more slender build than Aipyornis. A large part of the
skeleton of one of the new species is very briefly described.
The skull is said to be less flattened than that of Dinomis,
and at the same time narrower and longer ; the brain was
proportionately considerably larger. The mandible some-
what resembles that of Rhea, while the sternum ap-
proaches that of Apteryx in structure. The coraco-
scapula is small, and bears a shallow glenoid cavity for the

4o8 SCIENCE PROGRESS.

head of the rudimentary humerus. Further descriptions
and figures of this valuable specimen will no doubt be of
great service in settling the question of the affinities of the
family. The authors incline strongly to the view that
sEpyornis is closely related to Dinornis, and, as in their
former paper on this subject, suggest the former existence
of a land connection between Madagascar and New Zealand
to account for this relationship. In conclusion they state
that there is clear evidence that Aipyornis was contemporary
with man, and also mention that remains of a species of
Aphanapteryx and a large extinct anserine bird occur in the
same deposits.

In a later paper (20) the same authors describe in some
detail the skull of one of the smaller forms included in the
genus Mullerornis. This is said to differ widely from that
of JEpyornis, the cranial region being much less depressed
and the frontals raised so as to form a prominent boss. The
basi-pterygoid processes are only slightly developed, and the
anterior region of the premaxillae is more compressed and
forms a rounded keel above. Of all recent Struthious birds
the Cassowary is said to most resemble Mullerornis, both in
its cranial characters and in many points in the remainder
of the skeleton.

An interesting account of the mode of occurrence of the
bones and eggs of the JEpyornithida is given by Mr. J. T.
Last (21), who resided in the island for some time and made
collections in several localities. It appears that the bones
are usually found in the dried beds of ancient lakes or in
swamps, where they sometimes occur in large numbers ;
the eggs, on the other hand, are rarely found in such
places, but occur in great quantities (in fragments) in the
shifting sand-dunes round the coast.

In 1893 Professor Jeffrey Parker (22) published a new
classification of the Moas, founded on the characters of the
skulls. This paper is merely an abstract from his important
memoir on the cranial osteology of the group, which will be
noticed below. Here we need only mention that the
Dinornit hidce were subdivided into three sub-families, the
Dinormthince, Anomalopterygince, and the Emeince, and

DISCOVERIES IN AVIAN PALAEONTOLOGY. 409

that of all the genera Mesopteryx is considered to be the
least specialised, and retains most nearly the ancestral
characters of the family. At the same time it was also
shown that some species probably possessed a frontal
crest of large feathers, the points of insertion of which
are marked by a series of pits on the cranial surface ; in
some cases this character seems to have been a sexual one.

In the same year Hutton (23) published a paper which
may be regarded as an appendix to his important memoir,
"On the Moas of New Zealand," which appeared in 1892,
and consequently does not fall within the scope of the
present review. In this appendix the author states that in
his opinion it is necessary to subdivide the various genera
of the Dinornithidae into more species than had hitherto
been done ; since it is only by keeping the various species
and varieties distinct, that the relative ages of the various
superficial deposits in which their remains occur can be
ascertained. The method of subdivision employed by
him seems, however, to be open to the objection that it
is an extremely arbitrary and artificial one, for in his former
paper above referred to, as well as in the present one, he
relies mainly, and in many cases entirely, on measurements
of the long bones for separating the species. When we
consider that it is possible to trace an almost complete
gradation in size between the larger and smaller specimens
of any given bone, it is clear that the number of species
into which the series is divided, will depend upon personal
opinion as to the latitude to be allowed for individual
variation. In some cases where small differences in size,
accompanied by other slight variations, are constant in two
forms from different localities, the careful records and
measurements given by Professor Hutton are of much
interest and importance, but even in such cases it seems
better to regard such small differences as indicating local
races rather than distinct species.

Dr. H. O. Forbes (24) has severely criticised Professor
Hutton's methods, and points out that in some cases the
measurements given for one species fall within the limits
assigned to another.

4io SCIENCE PROGRESS.

Casts of a number of pieces of limb bones of a small
Moa, Anomalopteryx antiqua, which were discovered be-
neath a lava-flow at Timaru, are described and figured by
Hutton (25). These specimens were first noticed by
Forbes, who states that they were accompanied by re-
mains of Apteryx. As to the age of the deposits in which
these fragments occur there is much difference of opinion,
and they have been successively referred to the Eocene,
Miocene, Pliocene, and Pleistocene. Forbes believes
that they are Pleistocene or at latest Upper Pliocene,
while Hutton regards them as Miocene or Pliocene. In
any case the specimens, which have been lost, were so
imperfect that conclusions dependent upon them must be
received with caution.

In a subsequent memoir (26) by the same author the
structure of the axial skeleton in the various a-enera is dis-
cussed, and the descriptions of the various forms of pelvis
and sterna are very useful, as also are the references to the
published figures of various portions of the axial skeleton
of the different forms.

Some ten years ago De Vis announced the discovery
in Queensland of a femur of a species of Dinornis. The
occurrence of the New Zealand type of Ratite bird in
Australia would, of course, be a matter of great interest
and importance in questions relating to the geological
history of two areas ; but the great difficulty in accurately
determining isolated bird bones made it seem probable that
in this case a mistake had been made. This suspicion
would appear to be well founded, for Hutton, having
had an opportunity of examining casts of the type speci-
men of the so-called Dinornis Queenslandice, states (27)
that it differs widely from all Dinornithine femora with
which he is acquainted. He considers that the bone is
that of a bird related to Dromseus (the Emu), and coming
between that genus and Dromornis, an extinct Australian
form described by Owen.

The most valuable contribution to our knowledge of the
morphology of the Moas that has been published for many
years is Professor Jeffrey Parker's paper (28) on the cranial

DISCOVERIES IN AVIAN PALAEONTOLOGY. 411

osteology of the group. He has had opportunities of exa-
mining a very large number of skulls, some of which are
those of young individuals in which the sutures are still
open, and has, therefore, been able to give a very detailed
account of the structure of this, the most important portion
of the skeleton. Moreover, he has given a scheme of
classification of the group, founded exclusively on cranial
characters ; the importance of this is obvious to any one
acquainted with the terrible state of confusion into which, for
various reasons, the nomenclature of the Moas has got. Five
genera are recognised, and it would be very advantageous
if these could finally be adopted, particularly as they agree
in the main with those accepted by Lydekker in his cata-
logue of the British Museum collection, which, containing
as it does the types of most of the species, must be the
final court of appeal in most questions relating to the
nomenclature of the family. Professor Parker has added
a very detailed comparison of the Dinornithine skull with
those of the other Struthious birds, and arrives at some inter-
esting results as to the relationships existing between the
various types. He considers that the Ratitae are a poly-
phyletic group, Rhea and Struthio having originated inde-
pendently of one another and of the forms inhabiting
Australia and New Zealand. The latter arose from a
common stock which early divided into two branches,
the one giving rise to the Australian genera, Dromczus
and Casnarius, the other to the New Zealand forms. The
latter again divided into two branches, one leading to the
ApterygidcB, the other to the Dinornithidce. Of this family
Dinoruis and Emeus are regarded as having diverged most
widely from the ancestral type, which is probably most
nearly represented by Mesopteryx. This view differs from
that of Burckhardt mainly in the refusal to admit a common
ancestry of Struthio and the Casuariidae, otherwise it is in
general agreement with it, and is supported by the geo-
graphical distribution of the various forms. Unfortunately
palaeontology throws little or no light on the history of the
Struthious birds, no fossil form that can be referred to that
group with certainty being known from strata older than

4i2 SCIENCE PROGRESS.

the Pliocene. It is true that many extinct birds, as, for
example, the Gast omit hides and Stereornitkes, have been
referred to it, but in no case does it appear probable that
we have to do with either actual ancestors or even offshoots
of the ancestral Struthious stock. So far, therefore, as palae-
ontology is concerned we have no means as yet of deter-
mining the relations of the Ratitse either with one another
or with other birds, and it is on such studies of the com-
parative anatomy of the various groups, as that given by
Professor Parker in the case of the skull, that we must rely
for information on this point.

Numerous papers have appeared lately dealing with the
vexed question of the date of extinction of the Moas, and
the points of view from which the problem has been attacked
are very numerous. On the whole the evidence brought
forward seems in favour of the view, so ably advocated by
Dr. H. O. Forbes and others, that these birds have died out
comparatively recently, and that their extinction is mainly due
to the persecution they suffered from the Maoris, who hunted
them down for food, and probably also destroyed their
eggs. One of the reasons for believing that they survived
till quite lately is the occurrence of portions of their bodies
with dried flesh and feathers still adhering, several additional
instances of which have been brought to light during the
last year or so. Hamilton (29) has given a very interesting
account of the various finds of Moa feathers, and more par-
ticularly of one which he himself investigated. In this case
a large quantity of feathers, probably belonging to a species
of Megalapteryx, were found in a cavern near the head of
the River Waikaia, where a leg of the same bird with the
flesh and skin still adherent had previously been discovered.

Some important discoveries of remains of extinct birds
other than the Moas have been recently made in the New
Zealand region. In a fissure in the limestone at Castle
Rocks, Southland, Hamilton found an immense quantity of
the bones of birds which appear to have fallen into the
opening as into a pit-fall ; though this can hardly have been
the case with the large extinct eagles, Harpagornis, remains
of both species of which occur. The remainder are nearly

DISCOVERIES IN AVIAN PALAEONTOLOGY. 413

all flightless forms, including Anomalopteryx, a large species
Fulica, much like that found in the Chatham Islands (see
below), a small Weka-rail, Aptoruis, Notornis, and several
others. An account of these, together with elaborate tables
of measurements of the limb bones of some of them, will be
found in Hamilton's paper (30).

The most important of all the recent discoveries in this
region is, without doubt, that made by Dr. H. O. Forbes.
In 1892 (32) he announced in Nature that he had received
from the Chatham Islands (about 500 miles east of New
Zealand) a skull of a large rail closely resembling the
extinct Aphanapteryx of Mauritius ; to this the name Apha-
napteryx Hazvkinsi was given. A large collection of bird
remains, subsequently obtained from the same locality,
contained all the more important bones of many individuals
not only of this species, but also of several other extinct
forms. Among the more notable of these were a large
Coot, Fulica chathamica, very similar to the Mauritian
species, F. Newtoni ; a new type of Crow, Palccocorax
moriorum, said to be most nearly related to the Gymnorhine
group ; an extinct Swan, Chenopis, besides several other
species, most of which are still inhabitants of the Islands.
Several of the extinct forms have not yet been described,
but of Aphanapteryx Hawkinsi and Palcsocorax moriorum
a short account was published in the Ibis. At the same
time a new genus, DiapJiorapteryx, was established for the
reception of the former species. Subsequently, however,
the new name was withdrawn, and Forbes expressed his
conviction that the Chatham Island and Mauritius birds are
not generically distinct, and must, therefore, both be referred
to Aphanapteryx. This opinion he defends in a short paper
(34), illustrated by figures of the humerus, sternum, and
premaxillse of the two forms.

In a paper by the present writer (35), on the osteology
of the Chatham Island bird, a number of differences between
it and Aphanapteryx broecki are pointed out ; and some of
them, as, for example, the great dissimilarity between the
metatarsi, are clearly of generic value, so that the name
Diaphorapteryx was again adopted.

414 SCIENCE PROGRESS.

The assumed generic identity of these two forms was the
most important new evidence brought forward by Forbes in
his paper supporting the hypothesis of the former existence
of an Antarctic Continent ; but in the paper just referred to
(35) it was shown that, as far as the birds are concerned,
there is no evidence that the Chatham Islands have been
united with any land area, and that the presence of two
similar flightless rails on two islands remote from one
another is no proof of any former land connection between
them. In such a case it seems far more reasonable to sup-
pose that both the islands may have been colonised by the
same or allied forms of flying rails which have subsequently
lost their powers of flight, owing to the very fact of their
insular conditions of life. An instance of this on a smaller
scale is found in the case of Tristan d'Acunha and Gouo-h
Islands, which are about 200 miles from one another and
about the same distance from the Cape of Good Hope.
Each of these islands is inhabited by a distinct species
of Gallinule (Porphyriornis), which closely resemble one
another and are incapable of flight ; yet no one has sug-
gested that on that account these islands were formerly
united by land, either with one another or to Africa.

It is a fortunate coincidence that while the relationship
between Diaphorapteryx and Aphanapteryx was still in
dispute some additional remains of the latter were described.
These bones, together with those of many other species,
including the Dodo, Lophopsittacus mauritianus, Fulica
Newtoni, etc., were described by Newton and Gadow in
a well-illustrated memoir (36). Besides adding much to
our knowledge of previously known extinct birds, the
authors have been able to describe a number of new
ones. They have also published a figure of the restored
skeleton of the Dodo, which in several respects is more
correct than those which have previously appeared. The
whole of the remains described were obtained from the
Mare aux Songes, from which previously a large quantity
of Dodo bones had been collected. Besides the bones of
birds those of the large extinct lizard, Didosaurus, and
carapaces of Tortoises were found.

DISCOVERIES IN AVIAN PALEONTOLOGY. 415

BIBLIOGRAPHY.

(1) MARSH, O. C. A new Cretaceous Bird allied to Hesperornis.

Anier. Journ. Science, vol. xlv., p. 81, 1893.

(2) Marsh, O. C. On a Gigantic Bird from the Eocene of New

Jersey. Amer. Journ. Science, vol. xlviii., p. 344, 1894.

(3) Cope, E. D. On Cyphornis, an Extinct Genus of Birds.

Journ. Acad. Nat. Sci., Philadelphia, vol. ix., p. 449.

(4) Edwards, A. Milne. Sur les Oiseaux fossiles des Depots

Eocene de Phosphate de Chaux du Sud de la France.
Comptes Rendu s. Congrcs Omithologique International, Buda
Pesth, pt. ii. (Partie Scientijique), p. 60, 1892.

(5) Lydekker, R. L. On some Bird Bones from the Miocene of

Grive-St.-Alban, Department of Isere, France. Proc. Zool.
Soc, p. 517, 1893.

(6) AMEGHINO, F. Enumeracion systematica de las especias de

mamijeros Josiles colec. por C. Anicghino en los terrenos eocenos
de la Patagonia austral., p. 24, 1887.

(7) Ameghino, F. Aves fosiles argentinas. Revista Argentina

de Historia Natural, tome i., p. 255, 1891.

(8) Moreno and Mercerat. Catalogo de los Pajaros fosiles de

la Republica Argentina. Palceontologia Argentina, tome i.
(Anales del Museo de la Plata), 1891.

(9) Ameghino, F. Enumeracion de los aves fosiles de la Repub-

lica Argentina. Revista Arg. Hist. Nat., tome i., p. 441, 1891.

(10) GADOW, H. Bronn's Thierreich. Aves, tome ii. (Systemati-

scher Theil), p. 106.

(11) Lydekker, R. L. On the Extinct Giant Birds of Argentina.

Ibis, p. 40, 1893.

(12) Ameghino, F. Sur les Oiseaux fossiles de Patagonie. Boletin

del Instituto Geografico Argentino, tomexv., cap. 1 1 and 12, 1895.

(13) Lydekker, R. L. The La Plata Museum. Natural Science,

vol. iv., p. 126, 1894.

(14) Lydekker, R. L. The Giant Birds of South America. Know-

ledge, vol. xviii., p. 125, 1895.

(15) Andrews, C.W. Remarks on the Stereornithes. Ibis, p. 1 , 1 896.

(16) Burckhardt, R. Ueber ^pyornis. Palczontologische Ab-

haudluugen, Bd. ii. (Neue Folgc), p. 127, 1893.

(17) Andrews, C. W. Note on a New Species of ^Epyornis {/E.

Titan). Geological Magazine, 4th Dec, vol. i., p. 18, 1894.

(18) Andrews, C. W. On some Remains of yEpyornis in the

British Museum. Proc. Zool. Soc, p. 108, 1894.

(19) Milne Edwards and Grandidier. Observations sur les

^pyornis de Madagascar. Comptes Rendus Acad. Sci., t.
cxviii., p. 122, 1894.

29

4i6 SCIENCE PROGRESS.

(20) Milne Edwards and Grandidier. Sur des Ossements

d'Oiseaux provenant des Terrains Recents de Madagascar.
Bulletin du Museum d ' Histoire Naturelle, p. 9, 1895.

(21) LAST, J. T. On the Bones of ^Epyornis, and on the Localities

and Conditions in which they are found. Proc. Zool. Soc.,
p. 123, 1894.

(22) Parker, T. J. On the Classification and Mutual Relations

of the Dinomithidce. Trans. New Zealand Instil., vol. xxv.,
p. 1, 1893.

(23) HUTTON, F. W. New Species of Moas. Tow. eit., p. 6.

(24) Forbes, H. O. The Moas of New Zealand. Natural Science,

vol. ii., p. 374, 1893.

(25) HUTTON, F. W. On Anomalopteryx antiqua. Trans. N. Z.

Instit., vol. xxv., p. 14.

(26) HUTTON, F. W. On the Axial Skeleton in the DinornithidcB.

Trans. N. Z. Instit., vol. xxvii., p. 157, 1895.

(27) HUTTON, F. W. On Dinomis (?) QueenslandicB. Proc. Linn.

Soc, New South Wales, vol. viii. (2nd series), p. 7, 1893.

(28) Parker, T. J. On the Cranial Osteology, Classification, and

Phylogeny of the DinornithidcB. Trans. Zool. Soc, vol. xiii.,

P- 373, i895.

(29) Hamilton, A. On the Feathers of a Small Moa. Trans. N.

Z. Instit., vol. xxvii., 1895, p. 232, 1894.

(30) HAMILTON, A. On the Fissures and Caves at the Castle

Rocks, Southland ; with a Description of the Remains of
the Existing and Extinct Birds found in them. Trans. N. Z.
Instit., vol. xxv., p. 88.

(31) HAMILTON, A. Result of a Further Exploration of the Bone

Fissure at Castle Rocks, Southland. Trans. N. Z. Instit.,
vol. xxvi., p. 226.

(32) Forbes, H. O. On a Recent Discovery of the Remains of

Extinct Birds in New Zealand. Nature, vol. xlv., p. 416,
1892.

(33) Forbes, H. O. Ibis, p. 253, 1893.

(34) FORBES, H. O. On the Aphanapteryx of Mauritius and of the

Chatham Islands. Ann. Mag. Nat. Hist., ser. 6, vol. xii., p.
65, 1893.

(35) Andrews, C. W. On the Extinct Birds of the Chatham Is-

lands. I. The Osteology of Diaphorapteryx Hawkinsi.
Zoologies Novitates, vol. iii., p. J^, Tring, 1896.

(36) Newton, E., and Gadovv, H. On additional Bones of the

Dodo and other Extinct Birds of Mauritius, obtained by M.
Theodore Sauzier. Trans. Zool. Soc, vol. xiii., p. 281, 1893.

C. W. Andrews.

Science |3ragre

35.

No. 30. August, 1896. Vol. V.

LIGHT AND ELECTRIFICATION.

11.

Continued from vol. Hi., p. 1S5.

WHEN we come to consider how to imagine the
mode by which light discharges an electrified
surface, one of the first hypotheses is that it may be by a
kind of proof-plane action, the illuminated surface being
disintegrated and its charged molecules evaporated away,
taking their charges with them.

The first objection to such a hypothesis is that the dis-
integrating action of light ought to be otherwise perceptible
either to microscopic inspection or to a delicate balance
which should determine the loss of material.

It has, however, often been suspected that metals may
evaporate more or less, and the fact of their smell seems to
establish the fact, so it may be well to consider how small
a loss of material will serve to explain the observed loss of
electrification.

If we assume that each molecule so evaporated has the
ionic charge on one of its atoms reversed, or, more simply,
if we assume that each atom carries off a quantity of
electricity of the order io-11 electrostatic unit, its maximum
possible and customary value, then the amount of electricity
associated with the one gramme of evaporated silver is
900 contants or 3 x io12 electrodal units.

30

41S SCIENCE PROGRESS.

Now a silver plate 14 centimetres square, under certain
conditions of arc illumination, was found in the writer's
laboratory to lose negative electricity at the rate of 30
electrostatic units per minute when kept electrified to 80
volts in fairly free space. Hence the time that would
elapse before the above plate would lose a tenth of a
milligramme of its substance is ten million minutes or nearly
a century.

Such a ratio of loss as that could not be detected by a
balance, even in the case of silver, which is the substance
most suitable for detecting a small electrolytic loss by
weight. But now suppose that the discharge is not of so
atomic a character, but that little flakes or pieces of the
metal are driven off under the electric stress, so that the
charge per gramme lost is very much less.

In that case the disintegration of surface might be
perceived, but there are many difficulties in the way of
supposing such an action.

The electric tension even when on the verge of dis-
ruption, when the surface is charged to many thousand
volts, is by no means comparable to the forces of cohesion.

And the action of light occurs at so low a tension that
it is impossible that its action is a mere bringing down of
the limit at which disruptive discharge begins.

The action of light is much more like a quiet atomic or
molecular process than it is like a disruptive discharge from
the substance in bulk.

It may, however, be worth noticing that the electric re-
pulsive force experienced by an atom when 011 a surface
charged to the disruptive limit is not incomparably less than
the average force of cohesion acting on such an atom. The
tenacity of a metal may be taken as io9 cgs. units, or about
icr7 degree, per superficial molecule. The electric force
acting on an atom in a potential gradient of 30,000 volts per
centimetre, which is the disruptive limit under ordinary
atmospheric conditions, is about io-9 degrees — one-hun-
dredth of the average cohesive force ; so it would not be
unduly speculative to conceive it possible that circumstances
connected with heat and other motors should occasionally

LIGHT AND ELECTRIFICATION. 419

render individual atoms detachable under stresses approach-
ing so near to the average limit, and this would be one way
of representing disruptive discharge.

Against this, however, must be set the fact that the dis-
ruptive limit depends greatly on the atmospheric condi-
tions, on the pressure and nature of the gas in contact with
the metal ; therefore it would appear that even for disrup-
tive discharge we must look to an interaction between the
molecule of the metal and that of the medium in contact
with it, rather than to a simple disruption of the metal
alone.

What is certain is that the charge is carried away by
particles (atoms or otherwise) which travel along the lines
of force to the oppositely electrified surfaces. It may con-
ceivably be that the conveyers of charge are the electrons
themselves ; in other words, that the negative ends of the
lines of force are detached from the charged body under
the action of light, and that the line therefore promptly
shuts up. It is more probable, however, there are no such
detached electrons or atomic charges divorced from matter,
but that the negative charge is conveyed by material atoms,
whether they be the atoms of the metal or of the sur-
rounding gas. To examine the question whether the con-
veying atoms belonged to the metal or to the gas, a number
of experiments have been made in my laboratory with the
object of testing the presence of metallic particles or vapour
near an electrified metal rapidly discharging under the
action of light.

The metals most easy to detect in small quantities are
in general perhaps silver, iron and sodium. Silver, by its
reflecting power when deposited upon glass ; iron, by its
magnetic properties ; and sodium, by the light it causes a
non-luminous flame to emit. Silver plates, with their clean
edges opposed to the surface of plate glass, were oppositely
electrified so that any charge given off from the silver edge
should be deposited upon the glass as upon the dielectric of
a Leyden jar, and were kept thus strongly illuminated by
an arc light for hours ; the glass was then examined for
transparency. A decided deposit was found near the illu-

42o SCIENCE PROGRESS.

minated region, but there appeared nothing metallic about
it, and it was easily dusted off. It seemed to be merely
dust out of the air. So the experiment was repeated in a
dust-free chamber, containing air filtered slowly through
Ions' tubes of cotton-wool, and now not the faintest local
dimming of the surface could be observed, although the illu-
mination and electrification lasted for days. So the answer
for silver was in the negative.

Next a non-magnetic substance was hung in a powerful
converging magnetic field in the neighbourhood of clean
illuminated and oppositely electrified iron, to see if by con-
densation of evaporated iron, it was possible that it became
magnetic. A minute torsion-bar of copper suspended over
a clean, conical, vertically pointing electro-magnet's pole
was the best arrangement. There were difficulties about
this experiment on account of electrodal and other forces,
but so far as disturbance could be eliminated the result
for iron was also negative.

Then the most elaborate series of observation was made
on metallic sodium kept in an atmosphere of highly purified
hydrogen, the gas being supplied through a long series of
drying tubes, and kept burning as a small jet just after it
had passed over the sodium surface. By a mechanical
arrangement the sodium could be cut to a clean surface from
outside, and when the gas was pure this surface lasted a
fairly long time, and under illumination it discharged elec-
tricity supplied by several dry piles in series, so that a
considerable supply of electricity could be drawn from the
flame whenever light from an arc lamp was allowed to
fall on the sodium surface through a quartz window. The
flame was looked at either direct or through a small
spectroscope, and though the sodium line could not be kept
wholly absent, its occasional presence depended in no way
on whether the surface was positively or negatively or not
at all electrified, nor on whether the light was or was not
shining on it.

Hence I conclude that the discharge of electricity from
illuminated surfaces is not effected by evaporation of those
surfaces, but that the molecules which convey the charge

LIGHT AND ELECTRIFICATION. 421

belono- to something in the gas, and not to the illuminated
body.

It may be asked whether dust in the air has any part in
the action, but, so far as I can find, it has none at low
tensions. The discharge rate from the silver surfaces, for
instance, was just about as rapid in a dust-free atmosphere
as when dust was present.

The proof that the discharge is effected by molecules of
some kind, or at least by something which travels along the
lines of electrostatic force was given by Righi. He elec-
trified a small metallic cylinder of which only one generating
line was free from varnish, and therefore clean enough to dis-
charge electricity. This cylinder being negatively electrified
in front of an earthed plate, an exploring terminal of an
electroscope could ascertain which part of the plate was
receiving a charge, as the cylinder was rotated on its axis,
a movable slit being arranged in the plate for this purpose ;
and it was found to be always near one extremity of a circular
arc of which the discharging line constituted the other
extremity. He further found that if the illuminated body
were free to move it receded like an electric windmill,
proving that it had imparted its charge to something
possessing appreciable inertia.

The inertia of the gaseous particles would indeed cause
some divergence from the above circular orbits in which
the electrical force is urging them, but the force is so great
and the mass is so small that the deviation is not noticeable.
Moreover, the charged atom has to make its way among a
crowd of others by a process very similar to what occurs in
electrolysis, so that the path of the electric charge follows
almost accurately the line of electric force. In that sense it
may be said to represent the motion of an electron or free
electric charge, without committing the speaker to the
hypothesis that such charges divorced from their usual
boundary conditions on matter can really exist.

If a gaseous atom can receive a charge from an elec-
trified surface there is no difficulty in understanding what
it does with it, nor how, by such a process, the electrified
body gets discharged, but the difficulty is to realise how an

442 SCIENCE PROGRESS.

atom can so receive a charge. Under ordinary circum-
stances it is certain that gas molecules cannot acquire a
charge until the electrical tension rises to the disruptive
point; but there is a certain condition into which a gas can
be thrown, similar, if not identical, with that which chemists
speak of as dissociation, wherein a gas becomes a conductor,
that is to say, its particles do really act as carriers of electric
charges, and may be spoken of as detached and specifically
charged atoms.

Now in a vacuum tube, wTe learn experimentally from
Mr. Crooks, that at high vacua the negatively charged atoms
are vigorously repelled from a negative electrode, and,
shooting out from it in straight lines, constitute what are
known as cathode rays. It appears as if the electric
discharge itself were carried on in a vacuum tube by a quiet,
imperceptible, electrolytic action, originating at the anode or
positive electrode, that this discharge fills the whole tube
with positive electrification up to within a short distance of
the cathode. In this short distance there is accordingly a
steep potential gradient, and any stray negative atoms
finding themselves therein are shot out of it with immense
velocity, and constitute what are called cathode rays.
Some doubt has been felt as to the essential nature of
cathode rays, but there is hardly any good reason for the
belief that they are anything else than a stream of negatively
charged atoms of matter. They need not have recently
received a charge, their charge may be intrinsic ; what we
observe is their repulsion, not as if guided through a resist-
ing medium by electric force, but as if propelled violently
inside a thinned layer and left to the first law of motion
nearly.

Great interest has been felt in this cathode stream for
a quarter of a century, but within the present year its im-
portance has become immense owing to the discovery of
Rontgen that a surface on which the stream impinges be-
comes capable of emitting a novel kind of radiation which
travels even more persistently in straight lines, and is not
readily stopped by material obstacles. This discovery
must ultimately throw a great deal of light upon the whole

LIGHT AND ELECTRIFICATION. 423

subject, and it is over soon to attempt to forecast its
probable development ; nevertheless a partial attempt may
be made for what it is worth.

The new radiation appears to differ from ordinary
ultra-violet radiation only in the matter of wave-length.
Its wave-length is probably extremely short, not vastly
greater than the size of atoms, and all its other known
properties and peculiarities will follow from that according
to known theories of dispersion, especially the electro-
magnetic one of von Helmholtz.

Now this X radiation, when it falls upon an electrified
surface, discharges it, somewhat in the same fashion that
ultra-violet light does ; but whereas light discharges
electricity solely, or at any rate chiefly, of the negative sign,
this X radiation discharges both positive and negative ;
and indeed it seems to act by converting the gas or other
insulating material near a charged body into a conductor.
This it probably does by dissociating the substance into
charged atoms which are then free to act as carriers, and
speedily convey to a distance the charge of the electrified
body by journeys along the lines of force.

It may be that ultra-violet light acts in somewhat the
same way, but not in exactly the same way. The air is
transparent to ultra-violet light, it is not perfectly trans-
parent to X rays.

There is no difficulty in supposing that the X rays
dissociate some ingredient of the atmosphere, but there is
great difficulty in supposing ordinary ultra-violet light to be
able to do so. What the ultra-violet light chiefly does is
to promote or to create the conditions necessary for the
ready interchange of electric charge between gas and
solid ; and that this is so is practically proved by the great
importance of the nature of the solid surface, as well as of
the gas in contact with it. The gas seems indeed of
secondary importance, but the cleanness and oxiclisability
of the solid is essential to a rapid and ready discharge with
ordinary light from the visible spectrum. High ultra-
violet light can act indeed over a wider range, and where-
as light of long wave-length can only discharge negative

424 SCIENCE PROGRESS.

electricity, it is probable that light of extremely short wave-
length can discharge positive also, and from surfaces not
specially clean nor oxidisable.

The X rays seem to go farther in the same direction ;
that is to say, their activity does not appear to depend much
upon the nature of the surface, nor do they seem to discrimi-
nate much between positive and negative electrification.

We may surmise, then, that long-wave light is effective
in promoting discharge only when dissociated or incipiently
dissociated atoms are already present in the neighbourhood
of the surface. It is otherwise known that strongly electro-
positive substances, like clean sodium or zinc, are surrounded
by a number of electro-negative (chiefly oxygen) atoms,
straining to get at it. And, similarly, a negatively charged
surface may be surrounded by a number of straining posi-
tive atoms. Under these circumstances it is not difficult to
picture the result of impinging waves of light, and of the
electrical oscillations which they must necessarily set up, as
resulting in an interchange of electricity between the surface
and the gas which otherwise might not have occurred.

When positive electricity has thus been received by the
metal from the air under the action of light, detached nega-
tive ions will be left in the atmosphere, and these will be
repelled by the body if kept negatively electrified, and so
may constitute a kind of feeble cathode ray.

Thus it appears as if there were a sort of reciprocal
action ; the impact of light on a negatively electrified sur-
face results in the production of something akin to cathode
rays, and the impact of cathode rays upon a positively elec-
trified surface results in something akin to light.

Another instance of reciprocity has also been observed.
Certain substances exposed to X rays fluoresce strongly,
that is, emit light which in some cases persists an appreciable
time, and some of these substances when made to fluoresce
by exposure to light begin to emit X rays and continue to
emit them for long after, as has been observed by M.
Becquerel.

There is one matter dealt with in the last article which
requires more cautious handling than it then received, and

LIGHT AND ELECTRIFICATION. 425

that is the discharge of positive electricity — i.e., the recep-
tion of negative by certain substances. It is a phenomenon
which undoubtedly occurs as an experimental fact, but if
we proceed to look into the cause of it we find its detailed
character by no means so obvious Certainly it depends a
great deal on the surroundings, and there is reason to be-
lieve that if a positively charged body were surrounded by
a surface incapable of giving off negative electricity, then
the apparent discharge of positive might not occur.

The question is complicated by the simple facts (a) that
we cannot have a charged body without an equal opposite
charge on surfaces opposed to it, and (6) that every sur-
face reflects and scatters some of the incident light which
therefore partly falls upon the oppositely electrified sur-
face. Hence when a positively charged body loses its
charge, it may be not through a direct action of the light
upon itself, but by reason of the action of the reflected
and scattered light on the negatively electrified surfaces in
its neighbourhood.

On this hypothesis a surface which appears to lose
positive more quickly that negative is one which of itself
hardly loses any electricity at all ; it loses negative slowly
but it is exposed to surfaces which can emit it more quickly,
and hence when it is positively electrified and they are
inductively negative, it receives from them a negative
charge more rapidly than it was able to give one out.

A large number of exoeriments have been made in the

O J.

writer's laboratory to test this point, mostly by means of
regular reflectors so as to avoid scattered light as far as
possible ; the details are somewhat technical and trouble-
some, and the verydust of the air is apt to scatter a good
deal of active light ; but the result is, on the whole, to
substantiate the above-mentioned idea, which also possesses
the powerful support of Messrs. Elster and Geitel, that the
loss of positive electricity under the action of light is an
indirect and secondary phenomenon.

It appears, however, that under X rays both points of
electricity are discharged equally, and if these X rays are,
as everything now indicates them to be, an extension into

426

SCIENCE PROGRESS.

very much higher regions of the spectrum of transverse
ethereal vibrations, then it must become a question of degree
and of wave length, as implied above by the writer, and no
perfectly simple statement can be made.

The activity of ordinary sunlight in promoting the
discharge of electricity into the atmosphere is evidently a
question of great meteorological importance ; but it is enor-
mously affected by the condition of the earth's atmosphere,
At high elevations the rays are very active, but in valleys
the power is less, and on many days in a town there is
hardly any power left at all. The writer's assistant, Mr.
Davies, constructed a portable apparatus with which he
made many observations in Wales and other places during
last summer at different heights and at different periods of the
day. The results are such as might naturally have been
expected, but we do not yet know whether the sun
emits any X rays at all detectable in the higher region of the
atmosphere, or whether this latter variety of radiation is
an artificial product recently introduced by man into the
operations of Nature.

Oliver Lodge.

AN EXTINCT PLANT OF DOUBTFUL

AFFINITY.

IN two previous articles l some account has been given of
the genus Sphenophyllum, with special reference to the
structure of the strobilus. I now propose to add a brief
summary of our knowledge of this interesting type of
extinct plants, which has been fully dealt with by William-
son and Scott in their memoir on Catamites, Calamostachys,
and Sphenophyllum}

Every collector of Coal-Measure plants must be
familiar with the fragments of slender stems bearing
regular whorls of wedge-shaped leaves, which are fre-
quently found in the Upper Carboniferous shales, or in the
ironstone nodules of Coalbrookdale and other places.
Writing in 1822, Brongniart 3 describes and figures a
well-preserved impression of a species of Sphenophyllum
under the name Sphenophyllitcs cmarginatus, and speaks
of it as a plant without any living generic analogue. In
the classic Prodrome dune histoire des vegUazix fossiles, the
same author eives the following definition of this fossil
genus, and adopts the generic name Sphenophyllum i : —

" Tige simple, articulee ; feuilles verticillees, au nombre
de six a douze, distinctes jusqua leur base, cuneiformes,
entieres ou emarginees, ou meme bifides, a lobes plus ou
moins profondement lacinies, presque dichotomes. Fructi-
fication inconnue." It is unnecessary to give any historical
sketch of the various opinions expressed by later writers on
the nature of this characteristic plant, but we may at least
point out, that it has been held by certain authors that the
plant regarded by Brongniart and others as an autonomous
genus, was in all probability a particular form of calamitean
branch. Stur was one of those who held this view, and in

1 f' Science Progress," vol. i., p. 54, and vol. i\\, p. 261.

2 Williamson and Scott. 3Broni:r.iart (1). PI. xiii., fig. 8.
4 Brongniart (2), p. 6S.

428

SCIENCE PROGRESS.

his great work on Calamites, several specimens are figured
and described as evidence of the calamitean nature of
Sphenophyllum. A restoration of Calamites with spheno-
pylloid and other branches, given in his monograph, serves
to illustrate this view.1 More recent investigation has,
however, conclusively proved that Brongniart's original
definition holds good. There can no longer be any doubt
that Sphenophyllum is a very well-defined generic type
holding a somewhat isolated position in the plant king-
dom.

From structureless casts and impressions, we learn that
the genus is characterised by a comparatively slender
articulated stem bearing a series of superposed whorls of
leaves. The number of leaves in each verticil is always
some multiple of three, frequently six, or it may be nine,
twelve, eighteen, or more at each node. The leaves
have usually a wedge-shaped form, and the lamina is
traversed by dichotomously branched veins. In older forms,
again, the leaves are much narrower, and each segment in a
whorl has a single median vein. The narrow-leaved species,
such as Sphenophyllum myriophyllum Crep., etc., 2 cannot
always be readily distinguished from the well-known Astero-
'bhyllites form of foliage; but as Zeiller3 points out, a careful
attention to the general habit of the plant, and the presence
of bifui cations in the leaves, should enable us to separate
these two generic forms. Another feature worthy of
note is the hetrophylly occasionally exhibited by this
genus.4 The occurrence on the same plant of broad and
finely dissected leaves, naturally suggested to some authors 5
the idea of an aquatic plant ; but the histological features
are not such as are usually associated with water plants.

Examples of Sphenophyllum met with in English Coal-
Measures do not, as a rule, attain any considerable length.
By far the longest stem which has come under my notice is
one in the Geological Survey Museum in Vienna ; in
this specimen there is an axis 4 mm. in breadth with a
length of 85 cm., giving off a slender branch 61 cm. in

1 Stur, p. 69. 2 Zeiller (1), pi. lxii. 3 Zeiller (2), p. 674.

4 Schenk, pi. xliv., fig. 1 ; Seward, p. 3, fig. 1. Etc. 5 E.g., Newberry.

AN EXTINCT PLANT OF DOUBTFUL AFFINITY. 429

length. Occasionally long and narrow strobili are found
attached to the vegetative branches ; in external appearance
they resemble to some extent the corresponding structures
in calamitean plants, but a closer inspection at once reveals
a very distinct individuality for this type of strobilus.

In Williamson and Scott's work three specific forms of
Sphenophyllum are dealt with. We may first of all give a
short description of the general type of structure char-
acteristic of the genus, and afterwards attempt a diagnosis
of the specific characters.

Primary Structure of the Stem. — Traversing the young-
stem there is a single vascular cylinder or stele, consisting
of a triarch and centripetally developed axial strand of
xylem. A transverse section of such a stem shows in
the centre a triangular group of reticulate, scalariform,
and spiral tracheids, the latter having a smaller diameter
than the others, and constituting the three protoxylem
groups at the prominent angles of the solid vascular axis.
It is a fact of considerable interest, that we have in this
primary structure an arrangement and manner of develop-
ment of the tracheids which a student of Botany is always
taught to regard as characteristic of root rather than stem
structures. External to the xylem there is occasionally
preserved a thin-walled phloem tissue, and beyond this
may be recognised the pericycle or limit of the stele.
Passing beyond the central cylinder we have a thicker
walled cortex, of which the outermost layer or epidermis
has not been clearly preserved.

Secondary Structure. — On examining a series of trans-
verse sections of stems in different stages of secondary
growth, we find that the triangular group of primary
tracheids becomes gradually surrounded by radially dis-
posed rows of large elements, forming in older stems a
considerable thickness of secondary wood, in which, as a
rule, there is a striking uniformity in the diameter of the
tracheae. Smaller xylem elements occasionally occur, but,
as in the majority of Coal-period plants, there are no definite
rings of growth. The development of secondary xylem,
beginning in the interfascicular region, that is, in the broad

430 SCIENCE PROGRESS.

bays of the primary wood, soon extends to the fascicular
regions, and thus completely encloses the axial strand.
The amount of secondary wood naturally varies con-
siderably in different sections, the tracheids in a single
radial row varying from one to thirty-seven in number.
The medullary rays either extend as continuous lines of
parenchyma through the whole thickness of the wood, or
occur in the form of cell groups at the angles of the tracheids ;
in the latter case the apparently isolated clusters of paren-
chyma are united by connecting cells stretching across the
radial walls of the reticulately pitted tracheids. Owing to
the smaller diameter of the fascicular tracheae, the secondary
xylem exhibits a fairly obvious division into six groups,
three broader masses of interfascicular tracheids, alter-
nating with three smaller groups of radial rows of fascicular
tracheids, tapering towards the protoxylem angles of the
primary xylem.

The formation of periderm is another characteristic
feature in the secondary growth of a Sphenophyllum stem.
A phellogen or cork cambium appears to arise in the
pericycle, and at a later stage the phloem parenchyma
takes part in the development of cork tissue. It is often
a matter of some difficulty to distinguish between the true
phloem and the internal periderm. The latter consists of
short cells in regular series, the former being made up of
much longer elements, which may possibly be sieve-tubes.

Leaves. — The most perfect example of a petrified leaf of
Sphenophyllum so far described, is one figured by Renault.1
In transverse section the lamina is seen to be composed of
thin-walled loose parenchyma, with small groups of trac-
heids marking the position of the veins. The epidermal
layer on the upper and under surface consists of fairly
thick-walled cells, with indications of stomata. The most
distinctly preserved stoma has, however, been figured by
Solms-Laubach2 from the epidermis of one of the leaf
segments of a strobilus ; in this there are two narrow guard
cells with two larger subsidiary cells.

1 Renault (i), pi. ix., fig. 6; and (2), pi. xvi., fig. 1.

2 Solms-Laubach, pi. x., fig. 9.

AN EXTINCT PLANT OF DOUBTFUL AFFINITY. 431

Root. — As regards the roots of this genus we have but
little information. Renault1 has figured a small silicified ex-
ample from Autun, with a diameter of 2 mm. In the
centre there appears to be a diarch primary xylem bundle,
surrounded by concentric rows of reticulately pitted trac-
heicls. It is possible that two specimens figured by Felix,2
may representadventitiousrootsbeinggiven off from a.Sphc/10-
phyllum stem. He speaks of them as examples of lateral
branching, but their precise nature is, by no means, very
easy to determine.

Fructification. — The fructification of Sphenophyllum as
first described by Williamson and Zeiller,3 may be
thus defined : — An axis traversed by a triangular strand of
primary xylem tracheids, bearing at intervals of 1 "5 to
2-5 mm. similar leaf verticils consisting of a number of
linear lanceolate segments, fused in their lower portions
into an open funnel-shaped disc. The numerous sporangia
occur in 2 to 4 concentric circles on the upper surface of
each disc, in radial sections of a cone presenting the appear-
ance of a row of 2 to 4 sporangia between each whorl of
bracts. Each sporangium is attached to a slender stalk
springing from the upper surface of the leaf disc, and
terminates in a hooked tip facing the axis of the strobilus,
thus resembling the attachment of an anatropous ovule to
its funicle. Each sporangiophore possesses a strand contain-
ing a few xylem tracheids. At the point where the stalk or
sporangiophore passes into the sporangium, the epidermal
cells have thicker walls, and appear to represent an annulus,
the sporangia dehiscing by a longitudinal slit on the side
away from the stalk. The sporangia are isoporous, and the
spores have a reticulately marked outer membrane.

In a recent paper by Count Solms-Laubach4 an exceed-
ingly interesting addition is made to our knowledge of the
Sphenophyllum strobilus. While confirming in the main
the results arrived at by Zeiller, Williamson, and Scott, he
describes a new type of fructification from the neighbour-

1 Renault (1), pi. viii., fig. 5 ; and (2), pi. xv., fig. 6.

2 Felix, pi. vi., figs. 2 and 7.

3 See " Science Progress," vol. i., p. 54. 4 Solms-Laubach.

432

SCIENCE PROGRESS.

hood of Cracow. In this species, Bowmanites Romeri, Solms,
the sphorangiophores springing from the upper surface of
each whorl of bracts, bear at the apex two sporangia instead
of one as in previously known forms. Between each pair
of sporophyll verticils there are at least three whorls of
sporangia, the sporangia are almost sessile, and attached to
short sporangiophes in the same manner as in the fructifica-
tions already described. Each sporangiophore bifurcates
towards the distal end, and the sporangia are attached to the
diverging forks in much the samemannerastheovulesof^w?^
and Encephalartos are suspended from their carpophylls.
As regards the nature of the spores and the annulus-like
cells of the sporangial stalks, Bowmanites Romeri agrees
closely with the other forms. As happens so frequently in
pala^obotanical research, we are able to examine in detail
the characters of an isolated member of an individual plant,
without knowing anything of the other parts of the same
species. In the present instance we are ignorant of the
nature of the leaves which were borne by the stem to which
Bowmanites Romeri was attached. There can, however,
be little or no doubt that we have to do with a Spkeno-
pkyllum strobilus, differing in an important respect from the
ordinary type. The plants included in the genus Catamites
are known to have possessed cones of more than one type
of structure ; and it would appear that this was also the
case with Sphenophyllum. When our data are more com-
plete it may be possible to institute new generic terms for
plants which are now assigned to these somewhat compre-
hensive genera, but for the present it is better to err on
the side of too wide a meaning for generic terms, than to
attempt to found new genera on insufficient evidence.

In addition to a full account of Bowmanites Romeri,
Solms discusses at some length another sphenophylloid
strobilus originally described by Weiss as Bowmanites
Germanicus \ and suggests that this species as well as that
described by Binney under the name of B. Camdrensis2

1 Weiss, PI. xxi., fig. 12. Solms-Laubach, PI. ix., fig. 7.

2 Binney, PI. xii., figs. 1-3.

AN EXTINCT PLANT OF DOUBTFUL AFFINITY. 433

may be identical with Bowmanites Dawsoni of William-
son.

It remains for us to consider the probable systematic
position of this genus. It is undoubtedly a Vascular
Cryptogam, characterised like so many other Palaeozoic
representatives of the group by a considerable development
of secondary xylem and phloem.

Zeiller has expressed the opinion that Spkenophyllum
should be included in the Filicince, and in the neighbour-
hood of the ferns ; he institutes a comparison with Mar-
siliacecE and Ophioglossece. The French author draws
special attention to the distinct resemblance between the
sporangiophore of Spkenophyllum and the sporocarp stalk
in Marsilia. Subsequent writers have very properly
pointed out that we cannot well make use of this super-
ficial resemblance, in attempting to discover characters of
real morphological importance. The single sporangium of
Spkenophyllum differs in an important degree from the
elaborate sporocarp or highly specialised foliar structure of
Ma?-silia. The fossil genus is no doubt eusporangiate,
and in that respect comparable with Ophioglossum, but the
fertile spike of the latter differs widely from the sporangia
and sporangiophores of the former. Potonies * comparison
of Spkenophyllum with Salvinia does not render any
material assistance to our endeavours to assign the fossil
form to its true position. " We must be content for the
present to leave this remarkable genus in its isolated
position, in the hope that the extensive knowledge of its
organisation which we now possess may in the future afford
an adequate basis for comparison, when additional forms of
Palaeozoic Cryptogams shall have been brought to light." 2

This conclusion arrived at by Williamson and Scott,
and accepted by Solms-Laubach, may perhaps be best
realised by making use of the term SphenophyllecE as a
class designation. This has been done by Schenk in
Zittel's Handbtich der P alee onto logic? and is the course
followed in a recent paper by Kidston4.

1 Potonie. 2 Williamson and Scott, p. 946.

3 Zittel. 4 Kidston.

31

434 SCIENCE PROGRESS.

PTERIDOPHYTA.

Class — Sphenophylle^e.

Genus Sphenophyllum. — Brongniart 1828 (Sftkeno-
pkyllites, Bronguiart, 1822). Stems comparatively slender
( 1 *5 to 1 5 mm. ?), articulated, usually somewhat swollen at the
nodes, and marked by more or less distinct ribs and grooves
which do not alternate at the nodes, occasionally a single
branch given off at a node. Leaves in verticils, usually the
leaves of each whorl are equal in size, but may be unequal,1
in multiples of 3, 6, 9, 12, 18 or more. The leaves of
successive whorls superposed, not alternate ; varying in
form from cuneate, with narrow base and multinerved
lamina having an entire or toothed anterior margin, to
narrow linear uninerved forms, or with a deeply dissected
lamina having dichotomously branched segments.

Stem monostelic, with a triarch triangular strand of
centripetally developed primary xylem, consisting of
reticulate, scalariform and spiral tracheae ; the protoxylem
elements being situated at the blunt corners of the xylem
strand, from the angles are given off the foliar bundles, either
one or two from each angle.

Secondary xylem consists of radially disposed reticulately
pitted tracheae, developed from a cambium layer. Phloem of
thin walled tissue including sieve-pitted tube-like elements
and phloem parenchyma. Both xylem and phloem traversed
by medullary rays of parenchymatous cells. Cortex largely
composed of fairly thick walled cells ; and in older stems
cut off by the development of deep-seated periderm.

Fructification in the form of long and narrow strobili, in
some cases reaching a length of 12 cm., and a diameter of
14 mm. A slender axis bearing whorls of numerous linear
lanceolate bracts fused basally into a coherent funnel-shaped
disc, bearing on its upper surface sporangiophores 2 and

1 Zeiller (2), p. 675.

2 The strobilus of S. trichomatosum, Stur, figured by Kidston, is de-
scribed as having sessile sporangia. On this point see Williamson and
Scott, p. 942. An examination of Kidston's specimen certainly conveys,
the idea of sporangia without stalks, but the evidence is not conclusive.

AN EXTINCT PLANT OF DOUBTFUL AFFINITY. 435

sporangia. Isosporous, possibly in some forms hetero-
sporous.1

Sphenophyllum plurifoliatum. Williamson and Scott,
Phil. Trans., vol. clxxxv., p. 920, pis. lxxv., Ixxxiii., 1894.

Aster op kyllites Sphenopliylloides. Will. Phil. Trans.,
vol. i., p. 41, pis. i.-iv., 1874. [Type specimens from the
Coal- Measures of Oldham in the Williamson Collection,
British Museum.]

Many linear leaves in each whorl ( 1 8 to 24 ?). Surface of
young stems marked by three longitudinal grooves.
Medullary rays in the form of groups of parenchymals
cells in the spaces between the truncated angles of the
secondary tracheae ; the groups connected laterally by
means of radially elongated cells. Continuous rows of
medullary ray cells rare. Deep seated periderm.

S. insigne. (Williamson). Phil. Trans., vol. clxiv.,
p. 41, 1874, and Williamson and Scott. Phil. Trans., vol.
clxxxv., p. 926, pis. lxxvi., Ixxxiii., lxxxiv., lxxxv., 1894.

Aster op hyllites insignis. Williamson. Mem and Proc,
Manchester Lit. and Phil. Society, vol. iv. [4], p. 13, 1891.
[Type specimens from the Carboniferous beds of Burntis-
land ; in the Williamson collection, British Museum.]

Leaves probably not more than six in each whorl.
Cortex grooved in young stems. Tracheae of primary
xylem smaller in diameter than in .S. plurifoliatium.

S. plurifoliatum. — Longitudinal canal at each angle of
the primary xylem strand ; spiral tracheae more numerous
than in the preceding species. Outer cortex of thinner
walled cells than in .S*. plurifoliatum. Tracheae of secon-
dary xylem with scalariform markings on radial walls.
Medullary rays of regular rows, of one to two cells in
breadth, extending through the entire thickness of the
xylem. Phloem contains wide sieve- tube-like elements.
Deep-seated periderm.

In describing the fructification of Sphenophyllum, Wil-

1 Kidston, in his definition of Sphenophyllum, speaks of it as hetero-
sporous. The heterosporous example described by Renault is, however,
extremely doubtful, and as yet we have no actual proof of the heterospory
of this genus (see Kidston, p. 58 ; also Williamson and Scott, p. 942).

436 SCIENCE PROGRESS.

liamson and Scott adopt the generic name of Sphenophyllum,
while Count Solms prefers Binney's term Bowmanites. The
question of terminology in paleobotany is often a difficult
one. When we have very definite evidence that a cone
belongs to a certain genus, it would appear the obvious
course to speak of both under the same generic name. On
the other hand there is something to be said in favour of
retaining a special term for detached strobili, which cannot
be certainly referred to their respective vegetative stems.
In the case of Sphenophyllum Dawsoni (Will.) it may be, as
suggested by Zeiller, the strobilus of S. cuneifolium (Sternb.);
as our knowledge increases, detached cones must frequently
be referred to certain specific forms of stems, and the con-
fusion would probably be lessened if a distinct generic name
were in the first instance assigned to isolated cones. The
use of distinctive names for the fructification of genera has
been found convenient in the case of Lepidodendron, Sigil-
laria, and Calamites (Lepidostrobus, Sigillariostrobus, and
C alamo stachys). Such names suggest the strobili of the
different genera, and in looking through a list of species
one recognises at a glance those which stand for repro-
ductive structures. Solms does not adopt the generic
designation of the fructification of Sphenophyllum corre-
sponding to C alamo stachys, as he considers such a term as
Sphenophyllostachys too long and inconvenient. In coining
new names sesquipedalian words should, as a rule, be
avoided, but in discarding the genus Sphenophyllostachys
one is departing from a recognised and convenient custom
for a reason which hardly seems adequate. Bowmanites is
the older name, but now that its true position is known, it
should be replaced by a term which expresses the fact of
its connection with Sphenophyllum. I would suggest,
therefore, that the name Sphenophyllostachys be adopted
for the strobili of Sphenophyllum.

Sphenophyllostachys Dawsoni (Will.). {Mem. Man-
chester Lit. and Phil. Soc, vol v., p. 28, pis. 1-3, 187 1.)

Volkmannia Dawsoni. Ibid.

Bowmanites Dawsoni. Weiss. Steinkohlen Calamarien,
ii., p. 200, 1884.

AN EXTINCT PLANT OF DOUBTFUL AFFINITY. 437

Slender axis bearing alternating whorls of bracts (14 to
20), cohering basably and free distally as long linear segments
extending- upwards through about six internodes. A single
verticil of long and slender sporangiophores on each whorl
of bracts. The sporangiophores bend inwards at the apex
and bear single sporangia. Isosporous. Spores with spinus
outgrowths. Probably the strobilus of Sphenophyllum
cuneifolium (Sternb).

Sphenophyllostachys RoMERi(Solms-Laubach). Jahrb.
Geo/. Reichs. Wien, Bd. 45, Heft. 2, p. 225, Pis. ix. and x.,

i895- _

Axis and whorls of bracts similar to those of 5. Dazvsoni,

except that in each verticil of bracts the free linear seg-
ments extend nearer to the strobilus axis. More than one
whorl of sporangiophores on each whorl of bracts, probably
three. Each sporangiophore forked distally, and bearing
a sporangium on the inwardly bent tip of each diverging
branch. Isosporous. Spores similar to those of 5".
Dawsoni.

Genus Trizygia. Royle. Botany and Nat. Hist.
Himalayan Mts., p. 431, 1834.

This generic name was proposed in 1834 for a genus of
plants occurring in the Glossopteris flora of India.1 Little
is known as to its real affinities or structure, but Zeiller 2
has recently pointed out the doubtful generic value of its
characters, and he regards it as most probably a form of
Sphenophyllum. The slender stem bears verticils of wedge-
shaped leaves in three pairs at each node, the anterior pair
being smaller than the two lateral pairs.

BIBLIOGRAPHY.

Binney, E. W. Observations on the Structure of Fossil Plants in
the Carboniferous Strata. Palceontological Society, pt. ii., 1871.

BRONGNIART, A. (i). Sur la classification et la distribution des
vegctaux fossiles en general, 1822.

Brongniart, A. (2). Prodrome d'une histoire des vegetaux fossiles,
Paris, 1828.

1 For figures see Feistmantel, pis. xi. A. and xii. A. 2 Zeiller (2).

438 SCIENCE PROGRESS.

Feistmantel, O. The Fossil Flora of the Lower Gondvvanas.

II. The Flora of the Damuda and Panchet Divisions. Mem.

Geo/. Surv. India, vol. hi., Calcutta, 1881.
FELIX, J. Untersuchungen iiber den inneren Bau Westfalischer

Carbon-Pflanzen. K. Preuss. Geo/. Landesanst., p. 153, 1886.
KlDSTON, R. On the Fructification of Sp/ienopJiy/lum trichomatosum,

Stur, from the Yorkshire Coal Field. Proc. R. Phys. Soc.,

Edinburg/i, vol. xi., p. 56, 1890-91.
NEWBERRY, J. S. The Genus Sphenophy/lum. Journ. Cincinnati

Nai. Hist. Soc., p. 212, 1891.
POTONIE, H. Ueber die Stellung der Sphenophyllaceen im System.

Bericht. dentsch. bot. Gese//., Band, xii., Heft 4, p. 97, 1894.
RENAULT, B. (i). Nouvelles recherches sur la structure des

SphenopJiyllum et sur leurs affinites botaniques. Ann. Sci.

Nat. Bot. [6], vol. iv., p. 277, 1876.
Renault, B. (2). Cours de botanique fossi/e, vol. ii., 1882.
Schenk, A. In Richthofen's China, vol. iv., Berlin, 1883.
Seward, A. C. Sp/ienopJiyUum as a Branch of Asterophy/lites.

Mancliester Lit. and Phi/. Soc, p. 1, 1890.
Solms-Laubach, Graf zu. Bowmanites Romeri, eine neue

Sp/tenopJiylluni Fructification. Ja/irb. k. k. Geo/. Reichsanust.

Wien, vol. xlv., Heft I, p. 225, 1895.
Stur, D. Die Carbon-Flora der Schatzlarer Schichten. Abth. II.

Die Calamarien. K. k. Geo/. Reichs., vol. xi.; Abth. II., Wien,

1887.
WEISS, C. E. Beitrage zur fossilen Flora, III. Steinkohlen-

Calamarien, II. Abth. Geo/. Specia/karte Preuss. Thiiring-

Staaten, Band v., Heft. 2, Berlin, 1884.
WILLIAMSON, W. C, and Scott, D. H. Further Observations on

the Organisation of the Fossil Plants of the Coal-Measures.

Part I. Catamites, Ca/amostachys, and Sphenophy//um. Phi/.

Trans., vol. clxxxv. B., p. 863, 1894.
Zeiller, R. (i). Bassin houiller de Valenciennes. Etudes de gites

Minkraux, Paris, 1886.
Zeiller, R. (2). Sur la Valeur du Genre Trizygia. Bu/L Soc.

Geo/. France [3], vol. xix., p. 673, 1891.
Zittel, K. A. VON. Handbuch der Pa/a?onto/ogie. Abth. II.

Palaeophytologie. Schimper & Schenk, 1890.

A. C. Seward.

THE WORK OF THE PORTUGUESE
GEOLOGICAL SURVEY.

THE geology of the Spanish Peninsula is imperfectly
understood; but it is not without a special interest of
its own. It is here, if anywhere in Europe, that we should
expect to find among the more ancient faunas some indica-
tions ot a warmer temperature than prevailed farther north,
or of some other difference due to difference of latitude.
It is the only part of Southern Europe where there is a really
extensive development of the Lower Palaeozoic rocks ; but
unfortunately these are still almost unknown.

Of late years the re-organisation of the geological surveys
of Spain and Portugal has led to a great increase in our
knowledge of those countries, and the recent appearance of
a new part of the Comnmnica(pes da Direc(ao dos Trabalhos
geologicos de Portugal affords a good opportunity of recapitu-
lating what has been accomplished in that country.

It is impossible to look at this and the other publications of
the Portuguese Survey without a word of praise for the beauty
of the plates with which they are illustrated, and the admir-
able way in which they are printed. It is a painful reflection
to an English geologist that the inimitable work of our own
Geological Survey should be presented to the world in a
style so far inferior ; and that the enlightened Government
of a great empire should in this respect be so far behind
that of a small and not very wealthy country like Portugal.

We may, however, be allowed to express our regret that
so few of the memoirs of the Portuguese Survey are
accompanied by maps, for without a map it is extremely diffi-
cult to follow the text of a stratigraphical paper; and without
making a map it is, or should be, almost impossible for the
worker himself to be sure that his views are correct. We
regret too the long delay in the publication of a new edition
of the general geological map of Portugal. Delgado is
twenty years old, and although later information is else-
where available, it is surely time that the Geological Survey

440 SCIENCE PROGRESS.

should take upon itself the production of a map more in
accordance with modern needs.

By far the greater part of Portugal is occupied by ancient
rocks of Archaean and Palaeozoic age, and by eruptive
masses which probably belong to various periods. All the
higher mountains are formed of such rocks ; and it is only
in the plain of the Tagus and along the coasts that any later
beds are to be found. The most extensive area of Mesozoic
rocks forms a broken triangle with its base parallel to the
Tagus between Lisbon and Torres Novas, and its apex at
Oporto. Mesozoic rocks also occupy a narrow strip of
country along the southern shores of Portugal in the
province of Algarve. They are found too in the Serra da
Arrabida, which forms the prominent cape south of Lisbon ;
and at Sao Thiago de Cacem and Cabo de Sines farther
south. The largest area of Tertiary deposits is that which
forms the plain watered by the Tagus and its tributaries.

" Azoic " Rocks. — The so called Azoic rocks, in which
no fossils have hitherto been discovered and which are pre-
sumed to be older than the Cambrian, are best developed
east of the Tertiary basin of the Tagus in the province of
Alemtejo. But it cannot be said that their age has been
determined with certainty, and the supposed absence of
of fossils may be due to imperfect examination.

Lower Palceozoic. — In spite of the extensive area occu-
pied by schists and other rocks of supposed Palaeozoic age
undoubted Cambrian fossils have been found at only a
single locality in Portugal. So long ago as 1876, between
the "Azoic" rocks of Alemtejo and the Lower Carboniferous
of the borders of Algarve, Delgado recognised a series of
beds which he believed to be distinct from both ; and in
this series, near the mines of San Domingos, were found
Nereites and other forms which are usually believed to be
tracks of animals. They are quite insufficient to determine
the age of the beds, and it was chiefly from a lithological
resemblance to certain rocks in the North of Portugal that
Delgado referred them to the Cambrian (15).

More recently (21), however, trilobites have been dis-
covered near Villa Boim, some 10 km. west of Elvas ; and

WORK OF PORTUGUESE GEOLOGICAL SURVEY. 441

these trilobites appear to belong to the characteristic Cam-
brian families Olcnidcs and Conoccphalidce. Delgado, indeed,
compares them with the genera Liostracus and Lcptoplas-
ttis ; but unfortunately no figures have yet been published,
and all that the descriptions enable us to say is that they
probably belong to the Olenus group. This discovery is of
oreat interest, for at one time it was believed that the
Olenus fauna was absent in Southern Europe. Recently,
however, it has been found also in Sardinia.

The Ordovician and Silurian rocks are much better de-
veloped than the Cambrian, or at least they have been far
longer known and have yielded fossils much more abun-
dantly. One of the best known localities is that of Val-
longo, 10 km. E.N.E. of Oporto, where Sharpe obtained
a number of Ordovician fossils which were described by
himself and others (41). Recently, Delgado has published
a new list of the forms from this neighbourhood, and he re-
cognises three distinct horizons (19). But there is some
confusion in the identification either of the horizons or of
the fossils ; for from the third horizon he records, for
example, both the Lower Ordovician form Acidaspis Buchi
and the Silurian species, Phacops Doivningice. Most of the
Vallongo specimens are certainly Ordovician, and among
them are Placoparia, Calymene, Tristani and others, charac-
teristic of the Anoers slates of France.

At Bussaco, some 20 km. north of Coimbra, Silurian
fossils, as well as Ordovician, are found in some abundance.
The Ordovician beds consist of a lower division of quart-
zites, sandstones, black shales and limestones, with Caly-
mene Tristani, Placoparia Zippci, etc. ; and these are suc-
ceeded by ochreous argillaceous rocks with Phacops Dujar-
diui, etc. The Silurian is represented by blue shales and
argillaceous schists with graptolites, Cardiola interrupts and
the thin-shelled Orthoceratites which Forbes called Creseis
(38). Such forms are characteristic of our Lower Ludlow,
and to a certain extent of our Wenlock beds.

South of the Tagus, in the neighbourhood of the grani-
tic mass of Portalegre, Delgado has reported the presence
of Ordovician beds (15). They commence with a series of

442 SCIENCE PROGRESS.

quartzites containing numerous " bilobites," similar to those
which in the North of Portugal, and in parts of France, are
found at the base of the Ordovician system. It is unneces-
sary here to enter into the controversy concerning these
forms. Nathorst has given strong reasons for believing
them to be the tracks of animals ; but Delgado strongly
opposes this view and maintains them to be algae (16).

In the neighbourhood of Portalegre there is found also
a small patch of schists containing Monograptus and some
casts of bivalves (15). The relations of these to the sur-
rounding beds are unknown ; but if the graptolites are
correctly referred to the genus Monograptus, they must
certainly belong to the Silurian.

So far then as they are known, the Lower Palaeozoic
rocks of Portugal do not favour very strongly the view that
there was any very marked difference in Older Palaeozoic
times between the faunas of Northern and Southern Europe.
Nevertheless, P/acoparia, Calymene Tristci7ii, and Acidas-
pis Buchi, which are characteristic fossils in France and the
Spanish Peninsula, are by no means common in Britain,
although they have been found there. In short, we have
no sufficient data as yet to show how far the fauna of
Southern Europe resembled or differed from that of the
North.

Upper Palceozoic. — There is only one locality in the
whole of Portugal where the Devonian has yet been
recognised, and this is near the Ordovician quartzites of
Portalegre. A band of schists was discovered by Delgado
containing Phacops latifrons, Cryp/urus, and broad-winged
Spirifers (15).

The Lower Carboniferous on the other hand occupies a
wide area in the South of Portugal, where it forms the
greater part of the hilly region on the northern borders of
the province of Algarve. Like all the other Palaeozoic
rocks of Portugal, they have never been studied in detail,
but they consist of schists and grauwackes, without either
quartzites or limestones, and they contain Posidonomya
(like Becker i and Pargai), and Goniatites [cf. crenistrid)
{15). Hence it appears that the Lower Carboniferous

WORK OF PORTUGUESE GEOLOGICAL SURVEY. 443

belongs to the "Culm" facies so widely developed in
Central Europe.

The Upper Carboniferous is very restricted in extent,
and its distribution bears no relation whatever to that of
the Lower Carboniferous. From the character of the de-
posits, and the mode of their occurrence, there can be little
doubt that the Upper Carboniferous of Portugal was laid
down in comparatively small basins not unlike those of
the Central Plateau of France. It invariably rests uncon-
formably upon very much older beds, and consists very
largely of coarse conglomerates.

The most extensive area is met with in the North of
Portugal, where the coal measures form a band stretching
from the sea-coast at Espozendo (North of Oporto) in a
S.S.E. direction across the Douro as far as Pijao in the
province of Beira (22). The coal of this band near
Vallongo was taken by Sharpe to be of Silurian age

(41).

Farther north there is another band some 22 km.
long and 700 m. wide in the neighbourhood of Bussaco (38,
26) ; and lastly, South of the Tagus there is a very small
patch at Moinho d'Ordem near Alcacer do Sal (28).

The fossil plants from these three basins have been
described by several writers, and according to Gomes (22)
they indicate that the deposits of all three are of the same
age, viz., that of our Coal Measures. But Wenceslau de
Lima has recently revised the flora of Bussaco, and from
various considerations, and especially from the presence of
Walchia and Callipteris, he has been led to conclude that
the coal bearing deposits of Bussaco belong to the Roth-
liegende, or to the passage beds between Carboniferous
and Permian (26). He believes, however, that the coal of
the other basins is of somewhat earlier date. It is remark-
able that in the Bussaco beds a crustacean has been found
which W. de Lima refers to the genus Eurypterus

(27)-

Trias. — The Palaeozoic rocks of Portugal are uncom-
formably overlain by a series of red and white sandstones
and conglomerates, to which Choffat has given the name of

444 SCIENCE PROGRESS.

"gres de Silves ". North of the Tagus these sandstones
form the eastern border of the Mesozoic area, stretching in
a narrow band from Aveiro nearly to the town of Thomar.
South of the Tagus the " gres de Silves " is met with at Sao
Thiago de Cacem, at Carrapateira (N. of Cape St. Vincent),
and again as a narrow band resting upon the Palaeozoic
rocks in the littoral region of the province of Algarve (9).

North of the Tagus the sandstones begin to alternate in
the upper part of the series with dolomitic and argillaceous
limestones, and these in turn are surmounted by dolomites
without sandstone belonging to the Sinemurien (40). In
the lower or sandy part of the series there are several beds
which contain remains of plants. These have been exa-
mined by both Heer (23) and Saporta (40) and seem to
indicate a Rhaetic or Infraliassic aore.

The calcareous beds which occur higher up in the series
are called the " beds of Pereiros ". They often contain
marine fossils, for the most part gastropods and lamelli-
branchs, which are believed by Choffat to belong to
the Infralias.

In Algarve the general succession is very similar. The
red sandstones of the lower part of the series have yielded
no fossils. The dolomites of the upper part contain marine
forms ; and as in the north, the dolomites gradually increase
at the expense of the sandstones. They are overlaid by
marls, spotted with white, which often contain gypsum, but
no fossils (9).

Jurassic. — Jurassic rocks are found in four separate areas,
all of which are in the neighbourhood of the coast-line.
They extend, with some interruptions, from Aveiro in the
north of Portugal, to Cintra. They occur also in the
Serra da Arrabida, which forms the promontory south of
the Tagus which we call Cape Espichel. They are found
in the next important Cape to the south, the Cabo de Sines ;
and lastly, they are extensively developed along the coast
of the province of Algarve.

The system is divided by the Portuguese geologists
into three stages, corresponding with the three divisions
adopted in Central Europe and named in ascending order,,

WORK OF PORTUGUESE GEOLOGICAL SURVEY. 445

the Lias, Dogger, and Malm. There is, unfortunately, no
general account of the whole ; but Choffat has given us a
brief description of the Jurassic of Algarve (9), and a
fuller account of the Lias and Dogger (2) and of the lower
part of the Malm (12) north of Lisbon.

The Lias and Dogger are almost entirely marine, and
correspond very closely with the contemporaneous beds
of Central Europe. Many of the northern zones have
been recognised in Portugal and further research no doubt
will reveal others. It may be noted here that Choffat
includes the Callovian in the Dogger (5, 8).

The Malm, on the other hand, is a much less purely
marine formation, and in places contains beds of lignite,
which are sometimes, for example, at Cape Mondego,
extensive enough to be worked. It differs considerably
from that of Northern Europe, and is very variable in
character. Everywhere, however, it may be divided into
two stages, the Lusitanian below and the Neo-jurassic
above.

North of the Tagus the Lusitanian as it exists in
the country of Torres Vedras has been described by
Choffat (12). This area includes the chain of Montejunto
and the low-lying country limited on the east by the
Tertiary basin of the Tagus and on the south by the
Cretaceous rocks of the neighbourhood of Lisbon. The
Lusitanian beds rest upon Callovian deposits with
Peltocems athleta and Cosmocerus calloviense ; and they
themselves consist chiefly of limestones in the lower part and
of clays with banks of sandstone in the upper. The lime-
stones contain various Ammonites, among them several
Oxfordian forms ; while in the clays are found numerous
gastropods and lamellibranchs, which are mostly similar
to those from the Sequanian or Astartian of the jura.

Elsewhere, however, excepting in the eastern part of
Algarve, the Oxfordian fauna has not been discovered, and
the Sequanian rests directly upon the Callovian, but without
any visible unconformity.

In the Montejunto country the passage between the
Lusitanian and the succeeding Neo-jurassic beds is formed

446 SCIENCE PROGRESS.

by clays with Lima altemicosta. Sandstones alternate
with these clays and in the succeeding beds become pre-
dominant. They extend up to, and include the repre-
sentatives of the Portlandian.

South of the Tagus nearly the whole of the Malm, and
indeed nearly the whole of the Jurassic, consists of lime-
stones, dolomites and marly limestones, excepting in the
uppermost part, where coarse conglomerates are sometimes
found (9). But the various localities show very different
developments. In the eastern part of Algarve the series
is complete, but towards the west there are very consider-
able gaps in the succession. In Western Algarve and at
Carrapateira the lower part of the Lusitanian is absent.
During the Jurassic period, therefore, Eastern Algarve lay
under moderately deep water throughout, while the rest of
Portugal, with its shallow water and lignite deposits and its
interrupted sequences, seems during the deposition of the
Malm to have been in great part land and in part covered
only by shallow water. Portugal in fact is an exception to
the general rule which obtains through most of Europe,
that the close of the Lias period was marked by a great
extension of the ocean. Throughout Portugal the Lias is
entirely marine ; while the Malm is generally in part absent
and in part shows numerous brackish and lacustrine de-
posits (40).

Cretaceous. — The Cretaceous deposits occupy even a
smaller space than the Jurassic. They cover, however, a
good deal of ground immediately north of Lisbon ; and
several patches are found within the Mesozoic area farther
north ; while Cretaceous beds are also known in the
littoral region of Algarve.

Again M. Choffat is our chief authority. He has de-
scribed in some detail the Cretaceous of Cintra, Bellas, and
Lisbon (extending from Cabo da Roca to the Tagus) (4) ;
the Cretaceous patches of Torres Vedras, Peniche, and
Cereal farther north (11); and also the Cretaceous band in
Algarve (9). As in the Cretaceous of Southern Europe
generally, Rudistae are among the characteristic fossils,
although the genus Hippurites itself appears to be absent.

WORK OF PORTUGUESE GEOLOGICAL SURVEY. 447

Choffat divides the system into the following subdivisions
(in ascending order) : —

Infravalanginien.

, Valanginien.
Hauterivien.
Urgonien.
Beds of Almargem.
Eellasien.
Cenomanian Limestone.

Most of these subdivisions are the same as those adopted
in Southern France and bear the same names. The beds
of Almargem represent the Aptian, and possibly the Albian,
of northern geologists, while the Bellasien is in part, and
perhaps entirely of Cenomanian age. The " Cenomanian
Limestone " may possibly include the lowest part of the
Turonian ; but no higher beds of the Cretaceous are
known.

The difficulties which have been encountered in the
examination and correlation of the Cretaceous deposits of
Portugal, were due to the rapid changes in lithological
character which the beds undergo even in a very short
distance. The result of this has been that different fades
of the same horizon have often been described as different
horizons.

These rapid lateral changes were due without doubt to
the nearness of the Cretaceous coast-line. Even in the
Upper Jurassic, as we have already seen, transported
materials play a considerable part, and this is still more true
of the Cretaceous. Coarse sandstones and conglomerates
are here abundant.

There are only two districts, namely, the region of
Cintra and Bellas and that of Eastern Algarve, where the
base of the Cretaceous is represented by marine beds, and
both these districts are near the present sea margin. Here
the whole of the Cretaceous excepting the beds of Almar-
gem consists of marly limestones with a marine fauna.

In the Cintra area, for example, the beds from the In-
fravalanginien to the Urgonien, and the Bellasien also, con-
sist chiefly of marls and marly limestones. The beds of

448 SCIENCE PROGRESS.

Almaro-em consist of sandstones at the base and summit
and limestones in the middle, the respective development
of the sandstones and limestones varying greatly. The
Cenomanian Limestone consists of compact limestones with
some marly limestones and sometimes with beds of flint.
They contain Rudistes Sphaerulites, etc.

In the country of Bellas, which lies only 5 km. farther
east, sandstones are much more developed, and form not
only the Aptian but also the whole of the Valanginian.
Twenty kilometres north east of Bellas the sandstones
invade all that lies below the Bellasien. This is the case
also at Torres Vedras and Cereal ; and farther north still,
sandstones form nearly the whole of the Cretaceous.

As far north as Torres Vedras there is no gap between
the Jurassic and Cretaceous; but beyond this point the base
of the Cretaceous is absent, and the gap becomes greater
as we proceed farther north.

In general the coarseness of the material diminishes
towards the west ; and from this and the other facts noticed
we may conclude that in the region north of the Tagus,
during the Cretaceous period land lay towards the north
and east, and gradually sank, the sea attaining its greatest
extension in Cenomanian times.

In the extreme east of Algarve the lower part of the
Cretaceous (the Neocomian of many authors) is entirely
marine. At S. Joao-da-Venda it is replaced by sandstones
and conglomerates ; while in Western Algarve it is en-
tirely absent. Here again then, as in the Jurassic period, we
find that land lay in Western Algarve during a considerable
part of the time while the eastern part of the province was
under the sea.

Since both the Cretaceous and Upper Jurassic of
Portugal consist largely of shore deposits, it is not astonish-
ing that numerous beds of lignite have been discovered in
them, and that plants are very abundant. These have
been described in detail by Saporta, who finds a gradual
passage from the Jurassic to the Cretaceous flora without
any sudden change such as is met with in other parts of
Europe (40).

WORK OF PORTUGUESE GEOLOGICAL SURVEY. 449

Tertiary. — Towards the close of the Cretaceous period
there appear to have been considerable outbursts of basalt,
which at their base are interstratified with marls containing-
a terrestrial fauna. They may, perhaps, be connected with
the great outflows of North-western Europe ; but they have
not yet been properly examined, and up to the present their
age remains uncertain.

The Tertiary beds which occupy so much of the plain
of the Tagus and occur elsewhere in smaller patches have
not attracted much attention from the Portuguese geologists,
and little seems to have been written concerning them.

The more recent deposits, however, have been the
subject of various papers (13, 33, 39, 43), and evidence
has been brought forward showing the existence of
prehistoric man (1, 10, 17, 34-37), and also, in the higher
mountains, of the previous presence of glaciers (20, 44).
Striated blocks and other evidences of glacial action have
been discovered in the Serra d'Estrella.

" Tiphonic" valleys. — But perhaps the most interesting
problems in the whole of Portuguese geology are those
which concern the valleys called by Choffat " tiphonic ':
(3, 6). These are met with chiefly in the Mesozoic area
North of the Tagus. In all cases there is a level floor
bounded on several sides by hills of Jurassic rocks. The
floor is formed of reddish marls, the " Marls of Dagorda,"
and sometimes upon it rise low ridges of dolomite. Choffat
has shown that the dolomites contain fossils of the same
age as the Beds of Pereiros (Infralias), and he believes the
marls to belong to the same period. The marls appear
to clip below the Jurassic beds which form the hills surround-
ing the valleys ; but the lower beds of the Jurassic are
always absent. The appearance of a conformable sequence
is in fact merely deceptive and the valleys are bounded
by faults, the floor of the valley being raised so that the
Infralias of the floor abuts against the higher Jurassic beds
of the surrounding- hills.

Connected with these tiphonic areas are considerable
outbursts of ophite and teschenite (3, 6, 30, 31), and
Choffat has brought forward some evidence to show that

32

450 SCIENCE PROGRESS.

the eruptions and the formation of the valleys took place
in the Tertiary period.

Eruptive Masses. — Mention has already been made of
the basaltic eruptions which took place at the close of the
Cretaceous period, and of the outbursts of ophite which are
probably of somewhat later date. But it is probable, too,
that some of the great masses of eruptive granite which
are so prominent on the geological map of Portugal are at
least as recent as these. Ribeiro had long maintained that
the granite of Cintra was of Tertiary age, but he never
published his evidence. Choffat has shown that this granite
has sent out veins into the base of the Malm ; and as the
higher beds of the Malm and the whole of the Cretaceous,
up to the top of the Cenomanian, follow upon these without
any sign of disturbance, he holds that the granite cannot
have been intruded until after the deposition of the whole
series. It cannot therefore be older than Upper Cretaceous

One of the most interesting of the eruptive masses of
Portugal is that which forms the greater part of the Serra
de Monchique. This consists chiefly of elseolite syenite,
which seems to have forced its way into the Culm of this
region without ever reaching the surface. The gradual
cooling of this mass under great pressure has led to the
formation of some interesting varieties of dyke rocks
which have been described by various writers, and subse-
quent denudation has exposed the resulting igneous com-
plex (24 and 25).

BIBLIOGRAPHY.1

(1) Ben-Saude, Alfredo. Notice sur quelques objets prehis-

toriques du Portugal fabriques en cuivre. Contmun. Comui.
Trab. Geo/., vol ii., pp. 1 19-124, 1888-92.

(2) Choffat, Paul. Etude stratigraphique et paleontologique

des terrains jurassiques du Portugal. Le Lias et le Dogger
au nord du Tage. Seccao Trab. Geo!., 1880.

1 Many of the Portuguese memoirs are published both in French and
Portuguese. Where a French translation exists, the French alone is
quoted here. Purely palseontological works are not included except
where it has been found necessary to refer to them.

WORK OF PORTUGUESE GEOLOGICAL SURVEY. 451

(3) CHOFFAT, PAUL. Note preliminaire sur les vallees tiphoniques

et les eruptions d'Ophite et de Teschenite en Portugal.
Bull. Soc. Gcol. France, ser. 3, vol. x., pp. 267-288, 1882.

(4) CHOFFAT, Paul. Recueil de monographies stratigraphiques

sur le systeme cretacique du Portugal. Premiere etude ;
Contree de Cintra, de Bellas et de Lisbonne. Seccdo. Trad.
Gcol., 1885.

(5) Choffat, Paul. De l'impossibilite de comprendre le Cal-

lovien dans le Jurassique superieur. Covnnun. Coiiim. Trad.
Gcol., vol. i., pp. 69-87, 1883-87.

(6) CHOFFAT PAUL. Nouvelles donnees sur les vallees tiphoniques

et sur les eruptions d'ophite et de teschenite en Portugal.
Ibid., pp. 1 13-122.

(7) CHOFFAT, PAUL. Age du granite de Cintra. Ibid., pp. 155-157.

(8) CHOFFAT, PAUL. Sur la place a assigner au Callovien. Ibid.,

pp. 159-163.

(9) CHOFFAT, Paul. Recherches sur les terrains secondaires au

sud du Sado. Ibid., pp. 222-312, 2 pis.

10) Choffat, Paul. Sur une station prehistorique a Obidos et

sur la dispersion de l'Ostrea edulis aux temps prehistoriques
Commun. Coium. Trab. Gcol., vol. ii., pp. 158-160, 1888-92.

11) CHOFFAT, PAUL. Note sur le cretacique des environs de Torres

Vedras, de Peniche et de Cereal. Ibid., pp. 171-215.

12) Choffat, Paul. Ammonites du Lusitanien de la Contree de

Torres Vedras. Direc. Trab. Gcol. Port., 1893.

13) Choffat, Paul. Note sur les tufs de Condeixa et la

decouverte de l'hippopotame en Portugal. Commun. Dir.
Trab. Gcol., vol. iii., pp. 1-12, 1 pi., 1895-96.

14) Choffat, Paul. Notes sur l'erosion en Portugal. Ibid., pp.

17-22, 4 pis.

15) DELGADO, J. F. N. Sur l'existence du terrain silurien dans le

Baixo-Alemtejo. Seccdo Trab. Gcol, 1876.

16) Delgado, J. F. N. Etude sur les Bilolites et autres fossiles

des quartzites de la base du systeme silurique du Portugal.
Seccdo Trab. Gcol., 1886. Supplement, 1887.

17) DELGADO, J. F. N. Reconhecimento scientifico dos Jazigos

de Marmore e de Alabastro de Santo Adriao e das Grutas
comprehendidas nos mesmos jazigos. Commun. Comm.
Geol. Trab., vol. ii., pp. 46-56, 4 pis., 1888-92.

18) Delgado, J. F. N. Contributions a l'etude des terrains

anciens du Portugal. Ibid., pp. 216-228, 3 pis.

19) Delgado, J. F. N. Description d'une forme nouvelle de

trilobite Lichas (Uralichas) Ribeiroi. Comm. Trab. Geol.,
1892.

452 SCIENCE PROGRESS.

(20) DELGADO, J. F. N. Note sur l'existence d'anciens glaciers

dans la vallee du Mondego. Commun. Dir. Trad. Geo/.,
vol. iii., pp. 55-82, 2 pis., 1895-96.

(21) DELGADO, J. F. N. Sur l'existence de la faune primordiale

dans le Alto Alemtejo. Ibid., pp. 97-103.

(22) Gomes, Bernardino Antonio. Flore fossile du terrain

carbonifere des environs du Porto, Serra do Bussaco, et
Moinho d'Ordem pres d'Alcacer do Sal. Comm. Geo/.
Port., 1865.

(23) Heer, OSWALD. Contributions a la flore fossile du Portugal.

Seccdo Trab. Geo/. Port., 1 88 1 .

(24) Hunter, M. and H. ROSENBUSCH. Ueber Monchiquit, ein

camptonitisches Ganggestein aus der Gefolgschaft der
Elaolithsyenit. Tscherm, miner, petro. Mitt., N.F., vol. xi.,
pp. 445-466, 1S90.

(25) KRAATZ-KOSCHLAU, K. v. Der geologische Bau der Serra de

Monchique in der Provinz Algarve (Siid-Portugal). Verh.
natur. -medic. Vereins zu Heidelberg, N.F., vol. v., pp. 215-225,
1894.

(26) Lima, Wenceslau de. Noticia sobre as camadas da serie

permo-carbonica do Bussaco. Commun. Comm. Trab. Geo/.,
vol. ii., pp. 129-152, 1 pi., 1888-92.

(27) Lima, WENCESLAU de. Note sur un nouvel Eurypterus

du Rothliegendes de Bussaco (Portugal). Ibid., pp. 154-157,
1 pi.

(28) Lima, Wenceslau DE. Estudo sobre o carbon ico do

Alemtejo. Commun. Dir. Trab. Geo/., vol. iii., pp. 34-54>
1 pi., 1S95-96.

(29) Lima, Wenceslau de. Notice sur une algue paleozoique.

Ibid., pp. 92-96, 4 pis.

(30) MACPHERSON, J. Resume d'une Description des roches

mentionnees dans la Notice precedente [Choffat, 3]
Bull. Soc. Geol. France, ser. 3, vol. x„ pp. 289-295,
1882.

(31) MACPHERSON, D. J. Estudo petrographico das ophites e

teschenites de Portugal. Commun. Comm. Trab. Geol. Port.,
vol i., pp. 89-112, 1883-87.

(32) MACPHERSON, J. Etude des roches eruptives recueillies par

M. Choffat dans les affleurements secondares au sud du
Sado. Ibid., pp. 313-332.

(33) Magalhaes Mesquita, Egberto de. Apontamentes

acerca da regiao littoral comprehendida entre as lagoas de
Mira e de Esmoriz (dunas d'Aveiro). Commun. Dir. Trab
Geol., vol. iii., pp. 23-33, 1895-96.

WORK OF PORTUGUESE GEOLOGICAL SURVEY. 453

(34) Paula e Oliveira, F. Note sur les ossements humains

existants dans le musee de la Commission des Travaux
geologiques. Commun. Comm. Trab. Geo/., vol. ii., pp. 1-13,
pt. i., 1888-92.

(35) Paula Oliveira, Francisco de. Nouvelles fouilles faites

dans les Kioekkenmoeddings de la vallee du Tage. Ibid.,
pp. S7-8i.

(36) Paula e Oliveira, Francisco de. Antiquites prehistor-

ques et romaines des environs de Cascaes. Ibid., pp. 82-108,

3 pis-

(37) Paula e Oliveira, Francisco de. Caracteres descriptivos

dos craneos da Cesareda. Ibid., pp. 109-118.

(38) Ribeiro, Carlos. On the Carboniferous and Silurian For-

mations of the neighbourhood of Bussaco in Portugal. With
Notes and a Description of the Animal Remains, by Daniel
Sharpe, J. W. Salter, and T. Rupert Jones; and an
account of the Vegetable Remains, by Charles J. F. Bun-
BURY. Quart. Journ. Geol. Soc, vol. ix., pp. 135-161, pis.
vii.-ix., 1853.

(39) RIBEIRO, CARLOS. Description du terrain quaternaire des

bassins du Tage et du Sado. Comm. Geol. Port., 1866.

(40) Saporta, Le MARQUIS de. Nouvelles contributions a la

fiore mesozoique — accompagnees d'une notice stratigraphique,
par PAUL Choffat. Direc. Trab. Geol. Port., 1894.

(41) Sharpe, Daniel. On the Geology of the neighbourhood of

Oporto, including the Silurian Coal and Slates of Vallongo.
Quart. Journ. Geol. Soc., vol. v., pp. 142-153, pi. vi., 1849.

(42) Sharpe, Daniel. On the Secondary District of Portugal

which lies on the North of the Tagus. Quart. Journ. Geol.
Soc., vol. vi., pp. 135-201, pis. xiv.-xxvi., 1850.

(43) Vasconcellos Pereira Cabral, Frederico A. de. Es-

tudo de depositos superficicaes da bacia do Douro. Seccdo
Trab. Geol., 1881.

(44) Vasconcellos Pereira Cabral, Fred. A. de. Traces

d'actions glaciaires dans la Serra d'Estrella, Roches striees,
blocs erratiques, moraines. Commun. Comm. Trab. Geol.,
vol. i., pp. 189-210, 4 pis., 1883-87.

Philip Lake.

IODINE IN THE ANIMAL ORGANISM.

THE disease called Myxcedema is due to morbid con-
ditions of the thyroid gland in which it no longer
exercises its normal role in the metabolic cycle. It is now a
matter of common knowledge that injection of extracts from
the thyroids of other animals cures the disease, by replacing
the lost internal secretion of the diseased or absent gland.
This very remarkable practical outcome of physiological
research has prompted several investigators to attempt the
discovery of the active chemical substance secreted by the
thyroid by which that organ normally influences the
nutrition of the nervous system, and to which thyroid
extracts owe their efficacy. Though this search can hardly
yet be said to have completely attained its object many
interesting facts have come to light during its progress, and
by no means the least of these is the discovery that there
are certain substances in the thyroid which contain iodine
in organic combination ; as an integral part of living
animal structures this element was previously not known
to exist.

The work was carried out in Baumann's laboratory at
Freiburg, and began with an investigation by Ernst Roos 1
on the influence of the thyroid gland on metabolism. In
Roos' paper the history of the subject, so far as it relates to
the use of thyroid extracts in the relief of myxedematous
conditions is fully given. The experimental part of the
paper describes observations on human beings during
treatment, who showed a marked increase in the amount of
phosphoric acid which they excreted. The majority of the
experiments were, however, performed on dogs ; the thyroid
had been previously removed, and the gland was adminis-
tered as food to them. The excreta were analysed and com-
pared with those in healthy dogs. In the latter there is an
increase in the excretion of nitrogen (more than can be
explained by the nitrogen in the gland given) of sodium

1 Zeitsch. f. physiol. Chem., xxi., p. 19, 1895.

IODINE IN THE ANIMAL ORGANISM. 455

chloride and phosphoric acid. The rise in sodium chloride
does not last as lono- as the others.

In dogs without a thyroid, the increased excretion of
nitrogen and chlorine is even more marked, while that of
phosphoric acid is not so great as in healthy animals.
There is also a diuretic action.

Some attempts were made to separate and identify the
active substance of the thyroid, but this part of the research
was incomplete. So far as the experiments went they
showed that the material is very stable ; this was previously
known because good effects follow thyroid feeding ; the
substance is therefore one which is not altered to any extent
by digestive processes. The substance is probably proteid-
like in nature, though not an enzyme as Notkin1 considers.

This conclusion fits in very well with some previous
work done by Gourlay.2 Gourlay separated a nucleo-
proteid and an albumin from the thyroid ; he further
discovered that the colloid matter in the thyroid vesicles is
nucleo-proteid and if this passes into the lymphatics, as
some have described, he thought it possible that the nucleo-
proteid was the active agent. This contains nuclein, a
substance not affected by gastric digestion.

Later Frankel 3 separated from the thyroid a crystalline
material which he named thyreo-antitoxin ; this has the
formula C6HnN305 ; the evidence that this is really what
its name signifies cannot, however, be described as satis-
factory.

E Baumann 4 continued the search, and it was here that
he came across the substance he called thyro-iodin, which
is remarkable among animal products in containing iodine.
The glands were boiled for days with ten per cent, sulphuric
acid ; the liquid after cooling deposited a glocculent pre-
cipitate, which after extraction with alcohol is the substance
in question. It contains 9/3 per cent, of iodine, and it may

1 Wiener med. JVoche?isch., No. 19 and 20, 1895. Notkin named the
enzyme he supposed to be the active agent — thyreo-proteid.

2/ourn. of Physiol, xvi., p. 23. 3 Wiener med. Blatter, No. 48, 1895.
4 Zeit. physiol. Chew., xxi., p. 319, 1895.

456

SCIENCE PROGRESS.

be a derivation of nucleic acid as it contains 0*54 per cent,
of phosphorus, but it was not obtainable from the thymus
gland,1 nor from pure nucleic acid.

From the first Baumann was inclined to the belief that
here was the active substance he was looking for ; this
opinion was, however, expressed with considerable reserve
until he had thoroughly tested the hypothesis by experiment ;
and in this part of the investigation he worked with Roos.2

They separated the substance by the use of either sul-
phuric or hydrochloric (10 per cent.) acid. It is insoluble in
these reagents, the other constituents of the gland being
soluble. It is thus extremely stable, and is moreover not
altered by heat.

In the gland itself, thyro-iodin is, however, chiefly in
combination with the proteids. They found that the
proteids of the gland which can be dissolved out by saline
solution are an albumin and a globulin.3 It is with the
albumin 4 that the greater part of the thyro-iodin is com-
bined ; the globulin contains a small quantity, and a third
portion is free, that is, not combined with proteid matter at
all.

The following table gives some idea of the quantity of
iodine in the glands in human individuals.

1

/ weight
Organ.

dine in
Organ.

Q ©

>-> 0

Adult human thyroids-

-Average of 26 cases.

Freiburg

8-2 gr.

0 33

5) )5

„ 3° >>

Hamburg

4-6

0-83

)> >j

» 11 „

Berlin

7'4

0-9

Children's thyroids

39 »

I 0 or
( traces

1 Later (Baumann, ibid., xxii., p. 1, 1S96) small quantities were obtained
from calf's thymus.

2 Zeit. physio/. Chem., xxi. 481.

3 For other work in the proteids of the thyroid see Gourlay, loc. cit. ;
Notkin, loc. cit. ; Bubnow, Zeit. physiol. Chem., viii., p. 1. The last observer
found three proteids, one a globulin.

4 Query, Nucleo-albumin, W. D. H.

IODINE IN THE ANIMAL ORGANISM. 457

In the sheep's thyroid, the percentage of iodine varies
from 0'9 to 1*5 in the dry, and from 0*26 to 0*44 in the
fresh organ.

In dog's thyroid little or no iodine is found ; but the
amount is increased by feeding on dog-biscuit. This fact
together with the almost complete absence of iodine in the
thyroids of children makes an impartial onlooker rather
sceptical concerning thyro-iodin as the essential chemical
substance in the internal secretion of the thyroid.

Nevertheless Roos 1 maintains, and supports his con-
tention with numerous and exhaustive clinical records, that
this substance acts both in men and animals just like
thyroid extracts, or feeding on the gland. The resemblance
is seen in its action on the general system, in metabolic
processes, and in cases of disease (myxcedema and
psoriasis).

Other observers have not been so fortunate. Thus
Gottlieb 2 found in dogs after thyroidectomy that the
administration of thyro-iodin had no influence in preventing
the symptoms (convulsions, etc.) that follow this operation,
nor in delaying death.

Auerbach 3 suggests that this is because Gottlieb's pre-
parations were poor ones ; they only contained 2 "8 per cent,
of iodine.

The main practical question is therefore unsettled, and
must be left to future investigations to decide.

But as a point of scientific interest, the discovery of
iodine in the animal body remains as one of great im-
portance, and is the most startling of scientific discoveries
made of recent years in the domain of chemical physiology.

Iodine in the thyroid is, however, not a unique occur-
rence. Almost simultaneously with Baumann's announce-
ment, Drechsel 4 published a paper in which he showed
that iodine occurs in other structures in quite a different
part of the animal kingdom.

1 Zeit. physio!. Chem., xxii. p. 18, 1896.

2 Deutsch. vied. Wochenschr. xxii., 15, p. 235.

3 Centralbl. f. physiol., x., p. 133, 1896.

4 Zeit. f. Biol., xxxiii., p. 85, 1896.

458 SCIENCE PROGRESS.

The substance (gorgonin) of the horny skeleton of
Gorgonia cavolinii contains iodine in organic combination.
Gorgonin yields a decomposition with barium hydroxide an
amido-acid containing iodine (iodo-gorgonic rtr?V/QH8NI02)
which is crystalline, and has the composition of a iodo-
amido-butyric acid ; its constitution is, however, not yet
certain.

The living substance of the gorgonia contains no iodine
or only the merest traces ; it is of proteid nature and on
decomposition with hydrochloric acid yields, lysine and
probably lysatine.1

Gorgonin is also a proteid, it yields on decomposition
with hydrochloric acid, leucine, tyrosine, lysine, lysatine (?),
iodo-gorgonic acid and ammonia.

W. D. Halliburton.

According to Hedin's recent work (Zeit. physiol. Chem., xx., 186 ;
xxi., 155, 297), lysatine is a mixture of lysine and arginine. Arginine
(C6H14N40,) is a base originally separated from vegetable tissues by
Schulze and Steiger (ibid., xi., 43 ; Ber. d. deutsch. Chem. Ges., xxiv.,
2701), and subsequently found by Hedin to be a constant decomposition
product of proteids and albuminoids. It yields urea on treating its silver
salt with barium hydroxide.

PETROLOGY IN AMERICA.

1"^ HE material for study offered to the American
geologist is rich in many respects, and perhaps in
no branch richer than in petrology. The vast tracts of
Tertiary lavas along and to the west of the Rocky Mount-
ains, the peculiar igneous rocks on the east side of the
great watershed, the varied series of lavas, tuffs, and
intrusive masses in the Palaeozoic and older formations
of the Eastern states, the extensive areas of igneous and
other crystalline rocks in the Lake Superior region, the
Adirondacks, Canada, etc., all present many points of
interest, and much valuable work has already been done in
the description and study of these rocks. These results we
owe in large part to the United States Geological Survey
and that of Canada, and to various state surveys : Min-
nesota, New York, Arkansas, Texas, etc. Besides this
official work, systematic petrographic research has been
carried on at several universities and colleges, such as
Johns Hopkins, Columbia College, Yale, the University of
California, and others. It is proposed in this paper to
notice a few of the more interesting contributions from
American sources during the last two or three years ; but
in selecting from so large and varied a literature we are
compelled to confine ourselves to certain areas and certain
groups of rocks.

Among the older formations much attention has been
•given to the massive basic igneous rocks so extensively
developed in some parts of Canada and the United States.
Adams (i) has given us a very complete account of the so-
called " anorthosites " or felspar-rocks which constitute the
chief bulk of what has been named the Norian formation of
Canada. They are undoubtedly plutonic rocks of the
gabbro family, characterised, however, by a great prepon-
derance of plagioclase felspar, usually labradorite. Next in
importance, though much subordinate, to the felspar are
augite and hypersthene, or in the Saguenay district olivine.

460 SCIENCE PROGRESS.

An original parallel-structure or banding is found in some
of the rocks, and cataclastic structures are frequent. When
iron-ore is present, it is always highly titaniferous, and in
places there are in the anorthosite masses of ilmenite with
only subordinate olivine and plagioclase.

The similar and perhaps coeval rocks of the Lake
Superior region have been investigated by Lawson (2) on
the Minnesota coast. They are fresh, coarse-textured,
massive rocks composed almost wholly of felspar. This
has been stated by Winchell to be labradorite, while
Irving described it as anorthite. Lawson finds both these
varieties in the rocks of different localities. The only other
constituent present is a little augite, partly in grains, partly
in minute parallel inclusions in the felspar, and the rocks
are thus of remarkably simple mineralogical constitution.

Bayley has undertaken a general study of the basic
massive rocks of the Lake Superior region (3). The most
important instalment of his results deals with the great
eabbro mass at the base of the Keweenaw formation in
North-eastern Minnesota. This has sometimes been
regarded as a "flow," but he suggests that it is either a
great intrusion in the lower part of the Keweenaw or an
older eroded massive rock, upon which the latter has been
deposited. As the rock has the characteristic structure of
a plutonic mass, it is indeed difficult to believe that it can
have consolidated under superficial conditions. Its con-
stituent minerals are felspar, augite, olivine, and magnetite,,
and variations in the relative proportions of these give rise
to different types, very rich in one or other of these con-
stituents. A point of some theoretical importance is that
these constituents seem to be the same in rocks which
differ widely in total composition. The felspar is always
a basic labradorite ; the olivine is a hyalosoderite with 34
per cent, of ferrous oxide ; the magnetite is not titaniferous
in the normal rock, and the aggregates of titaniferous iron-
ore well known in Minnesota belong to rocks differing
in various respects from the great mass.

Near the base of the main mass of gabbro, along its
northern edge, occur a number of partially banded rocks of

PETROLOGY IN AMERICA. 461

more basic nature, which the author ascribes to processes
of differentiation in the gabro-magma during its cooling.
These include various peridotites and pyroxenites, or as
Bayley names them, to mark their affinities, " non-felspathic
gabbros ". There are olivine-pyroxene rocks, varying- to
pure oli vine-rocks ; pyroxene-aggregates ; pyroxene-magnetite
rocks ; and rocks containing up to 90 per cent, of titaniferous
magnetite. Analyses of this magnetite have yielded from
2 to 16 per cent, of titanic acid. Associated with these
various basic modifications of the gabbro are rocks differing
from the normal gabbro in possessing the granulitic struct-
ure. They differ also to some extent in mineralogical
constitution, hypersthene largely taking the place of the
olivine, while the augite is more or less replaced by biotite
and hornblende.

It is well known that rocks of the gabbro family, closely
comparable with those of Canada and of the Lake Superior
region, are largely developed in the Adirondacks, in the
northern part of the state of New York. A large part of
these rocks are "anorthosites," composed mainly of labra-
dorite felspar with only subordinate augite and hornblende
and usually some red garnet, perhaps secondary. The
rocks are much affected by cataclastic structures. These
anorthosites form the heart of the mountain region, while
more basic gabbros constitute the smaller outlying intrusions
and minor portions of the main ridges. The latter rocks
have been described by Kemp, as they occur on the eastern
side of the mountains, along the western shore of Lake
Champlain (4). The felspar seems as before to be labra-
dorite : the other minerals are augite, hypersthene, titani-
ferous magnetite, and occasionally olivine. In places there
are bodies of iron-ore with ] 3 to 16 per cent, of titanic acid,
and these are regarded as representing an extremely basic
phase of the gabbro magma itself.

These iron-ores are described in more detail by the
same author in a bulletin dealing with the geology of two
townships in Essex County, N.Y. (5). The ores are all
essentially of magnetite, but those of Westport township
are of little value on account of the considerable amount of

462 SCIENCE PROGRESS.

titanic acid which they contain, while those of Moriah
are practically free from that substance. The titaniferous
ores occur in the gabbro, the non-titaniferous in the gneiss
of the district. In Canada, Lawson has pointed out exactly
the same distinction between the magnetite, whether dis-
seminated or collected in rich bodies, of the oabbros and
anorthosites and of the gneiss, respectively.

Smyth (6) has given an account of the different varieties
of gabbro in the north-western part of the Adirondacks.
One kind consists mainly of felspar and augite, the latter
often converted into compact hornblende, but the relative
proportions of these constituents vary greatly. The com-
monest type is very rich in the ferro-magnesian minerals,
but there are rapid transitions into a highly felspathic rock.
The felspar is in general labradorite, but in the more
felspathic varieties of the rock it is a more acid species,
with perhaps some orthoclase. Another type of gabbro is
hypersthene-bearing. The most interesting, however, is a
rock consisting of dominant felspar, with some augite, etc.,
and showing- cataclastic structures. The felspar ranges
from a highly twinned plagioclase to a fibrous microperthite,
and from a petrographic point of view the rock shows
transitions from a gabbro or anorthosite to an augite-syenite.
The latter has 65^ per cent, of silica, and about 5 per cent,
each of potash and soda. In contrast with the Minnesota
gabbro, we notice here that, as the rock varies, the minerals
(at least the felspars) vary with it, indicating clearly that
the differentiation has here been effected prior to the
crystallisation of those minerals.

Without citing other papers on the gabbros and allied
rocks of the North American continent, we may briefly
advert to two or three points of general interest brought
out in the works summarised above. One question of
considerable petrological importance relates to the so-called
"reaction-rims" which often surround the crystals of
certain minerals. These consist of one or more zones of
various silicates, etc., interposed usually between some
ferro-magnesian mineral and the plagioclase felspar. The
phenomenon is common in other districts of America and

PETROLOGY IN AMERICA. 463

Europe. The name applied to it assumes that the border-
ing minerals are of secondary origin, due to reactions
between the felspar and the ferro-magnesian silicate or
iron-ore orain, and several writers have ascribed the effect
to dynamic metamorphism ; but on these questions there
is by no means a common agreement. In the Canadian
anorthosites Adams (1) records a zone of red garnet as
frequently occurring between pyroxene or iron-ore grains
and felspar. In other cases he notes two zones between
olivine and felspar, the first being of a pale rhombic
pyroxene, the second of pale green actinolite needles, set
perpendicularly and sometimes having parallel interposi-
tions of deep green spinel. He finds no evidence of these
rims being a secondary effect due to dynamic causes. In
the great gabbro mass in Minnesota, as described by
Bayley (3, 7), the olivine is often surrounded by a narrow-
border of diallage or augite which thus intervenes between
it and the felspar. This border seems to be certainly an
original growth, for it is sometimes seen to be continuous
with a crystal-plate of diallage. Elsewhere there is a
fibrous intergrowth of the bordering augite with the
contiguous labradorite, and this is found surrounding
magnetite as well as olivine. Biotite is also found inter-
posed between magnetite and plagioclase, and this Bayley
considers due to a reaction, but his reasoning is scarcely
convincing. In the anorthosites of the Adirondack^ Kemp
states that there are no reaction-rims, although the rocks
give evidence of great dynamic disturbance. In the
basic gabbros, however, he describes a considerable variety
of borders round pyroxene, olivine, and magnetite. Between
augite and felspar is interposed a zone of brown hornblende
crystals ; between magnetite and felspar a first zone of
brown hornblende and a second of garnet. In this latter
case there may be additional zones, such as biotite
immediately surrounding the magnetite, or clear quartz
between the hornblende and the garnet. A curious feature
is a parallel or micrographic intergrowth of the garnet with
the adjacent felspar. Between olivine and felspar are seen
in some cases three successive zones, respectively of granular

464 SCIENCE PROGRESS.

hypersthene, quartz, and garnet ; or again a zone of brown
hornblende followed by one of garnet. While speaking
doubtfully of the hornblende and biotite, Kemp considers
the garnet certainly secondary on account of its peculiar
relation to the felspar. The quartz he regards as the
residual silica liberated in the conversion of labradorite to
garnet. In view of the great variety of micrographic inter-
growths known to occur as original products in various
igneous rocks, the secondary origin even of the garnet in
this case seems to be by no means conclusively established.
The hypothesis of secondary reactions is confronted in some
cases by chemical difficulties ; thus, it is not easy to see
how brown hornblende can be produced by reactions
between auoqte and labradorite, or biotite from magnetite
and labradorite. It is, however, true in a general sense,
as has often been pointed out, that the rims are usually
more or less intermediate in chemical composition between
the minerals which they separate. Allowing due weight to
this fact, it is still to be observed that the succession of
zones is in general what would be expected if the minerals
had crystallised out from a molten rock-magma, following
the normal order of consolidation of the several minerals
as laid down by Rosenbusch. It is also a common feature
in undoubted products from igneous fusion that the earliest
formed minerals tend to serve as a nucleus for the crystallisa-
tion of those that follow, and this is most noticeable in
plutonic rocks of basic composition. Further the "celyphite"
borders round garnets, and other similar phenomena, afford
numerous examples of radiating fibrous arrangement, and
linear parallel intergrowth of different minerals, which in
many cases are, beyond reasonable doubt, of primary origin.
It seems, therefore, that we must require more convincing
proof before accepting the view that the "reaction-rims" in
these gabbro-rocks are in general, or in any considerable
part, really due to secondary reactions between the original
constituent minerals.

Another interesting feature in these American gabbros
is the occurrence in them of considerable bodies of iron-ore,
which have clearly been secreted from the gabbro-magma

PETROLOGY IN AMERICA. 465

itself. Vogt has recognised among iron-ores thus connected
with basic igneous rocks two chief types, one characterised
by titaniferous iron-oxides, the other by nickeliferous iron-
sulphides. Some of the former we have already referred to,
but examples of the latter are also known in America, the
case of Sudbury in Canada being cited by Vogt. Kemp (8)
has recently described an occurrence in Pennsylvania, in
which the relations are very clearly exhibited. The ore is
associated with a dark basic rock, now consisting mainly of
hornblende but probably an amphibolised norite or gabbro,
which forms a lenticular mass some 500 yards long. The
ore occurs as a marginal modification of this rock, and
consists of nickeliferous pyrrhotine and copper pyrites with
some iron pyrites and secondary millerite (nickel sulphide).
These minerals are associated with a certain amount of horn-
blende in such a manner as to show that they must have
been original constituents of the rock.

The Adirondack gabbros afford some fine examples of
contact-metamorphism. The phenomena are most striking
at the contact of the gabbros with the crystalline limestones
of the district, and some well known-mineral localities fall
under this head. As described by Smyth (6), the lime-
stones become more coarsely crystalline as they approach
the gabbro, and pass finally into a zone consisting of various
lime-silicates and other special minerals, up to one or two
feet in width. In one occurrence this zone consists of
fibrous white wollastonite and grains of green pyroxene,
with some sphene and garnet. At other localities there are
several bands parallel to the junction, the one in contact
with the intrusive rock being of wollastonite, the next a
mixture of felspar, pyroxene, scapolite, sphene, zircon, etc.,
and then coarsely crystalline calcite with much pyroxene.
Again, a layer of scapolite may occur in immediate contact
with the orabbro. Another mineral recorded is orthoclase in

o

well formed crystals, while phlogopite mica is generally distri-
buted. The author considers that there must have been
actual chemical reactions and interchange of material
between the intruded magma and the limestone. The
gabbro itself shows some modifications at the contact, the

33

466 SCIENCE PROGRESS.

chief mineralogical feature being the coming in of abundant
little grains of sphene, which indeed seems to point to a
local enrichment in lime. On the western shores of Lake
Champlain, again, Kemp (4) describes the limestones as
becoming coarsely crystalline near the gabbro and charged
with bunches of various silicates and other minerals :
quartz, plagioclase felspar, diopside, hornblende, scapolite,
brown mica, pyrrhotite, tourmaline, sphene, etc. Scapolite
is characteristic in this connection throughout the region,
and is always accompanied by pyroxene and hornblende.
Further details are given in a later paper (9). The crystal-
line limestones are associated with various gneissic and
schistose rocks, doubtless also metamorphosed sediments,
and in the upper part of the series come serpentinous lime-
stones or ophicalcites. In the best sections, at Port Henry,
the bunches or patches of silicate-minerals, etc., enclosed in
the limestone range up to masses twenty-five to fifty feet
thick. They consist generally of a coarsely crystalline
aggregate of plagioclase, quartz, and hornblende, with
various other minerals as mentioned above. The serpentine
in the ophicalcites, as Merrill had already shown, has been
mainly derived from pyroxene, but Kemp finds evidence
that garnet has also furnished a part. The rocks also con-
tain lenticular patches composed of pyroxene, hornblende,
sphene, and phlogopite. These serpentinous rocks occur
in the limestones on the west as well as on the east side of
the Adirondacks.

Much attention has been given in recent years to the
various igneous rock-types rich in alkalies which occur in
the region east of the continental water-shed. A number
of interesting examples have been described by Weed and
Pirsson from the State of Montana. Two types of phono-
litic dyke-rocks were first discovered as boulders, but
subsequently traced to their sources in the Bear-Paw
Mountains (10). One, styled pseudo-leucite sodalite
tinguaite, is of interest especially as containing the pseudo-
morphs of orthoclase and nepheline after leucite already
known in Brazil, Arkansas, etc., while fresh sodalite is also

PETROLOGY IN AMERICA. 467

very abundant. The other, described as quartz-tin<;uaite
porphyry, corresponds very closely with Brogger's grorud-
ite, differing chiefly in the presence of large porphyritic
crystals of orthoclase. Besides a variety of intrusive rocks,
there occur in the Bear Paw Mountains a series of basalts,
probably leucitic, but of these no description has yet
appeared.

In the Highwood Mountains (11) in central Montana
similar basaltic tuffs and flows occur, while distinct volcanic
cores are seen breaking" through the level Cretaceous strata,
which are further cut by a large number of dykes with a
radial disposition. The most interesting feature, however,
is the laccolitic intrusion which forms Square Butte, an
isolated mountain some three or four miles in diameter, and
rising about 2500 feet above the surrounding plateau.
The laccolitic character of the mass is clearly demonstrated,
and its structure has been laid bare by erosion. It consists
of two types of rock, an inner portion of an acid felspathic
type surrounded by a zone of a basic augitic one. The
former is a sodalite-syenite consisting of sixty-six parts of
felspar, twenty-three of hornblende, eight of sodalite; and
three of analcime : it has already been described by Lind-
gren and Melville. The dark type is a syenitic rock, in
that its dominant felspar is orthoclase, but it constitutes a
peculiar basic variety to which the name shonkinite is given.
Augite, containing; 1 per cent, of soda, makes up about half
the rock, olivine and iron-ore occur in smaller amounts,
while apatite, sodalite, nepheline, etc., are accessories.
Chemical analyses of the two rocks show a notable difference,
the former being richer in silica, alumina and alkalies, the
latter in iron-oxides, magnesia, and lime. Examination
proves that they are parts of a single intrusive body of
rock, though the transition from one to the other is a rapid
one. The phenomena seem to show conclusively that the
magma was injected in a homogenous condition, and was
differentiated in place. That the differentiation was, at
least in part, effected prior to crystallisation appears from
the difference between the ferro-magnesian minerals of the
two rocks.

468 SCIENCE PROGRESS.

The same authors have studied certain allied rocks
occurring- at Yogo Peak in the Little Belt Mountains, also
in Central Montana (12). These rocks form parts of a
mass two miles long and one mile wide occupying a great
fracture in the Palaeozoic strata. At the eastern point of
the peak occurs a syenite with 61^ per cent, of silica and
moderately high percentages of magnesia and lime. It is
an augite-syenite, though with subordinate hornblende.
Westward it gradually changes character in the sense of
becoming more basic, until at the summit it contains as
much augite as orthoclase. This type, which has about 54^-
per cent, of silica, has been named yogoite. At the
western point of the peak the augite predominates over
the orthoclase, while biotite and iron-ore also become
prominent, and pseudomorphs after olivine are sometimes
found. The rock here is a shonkinite similar to that of
Square Butte. The silica percentage has fallen to 49, while
the amounts of iron-oxides, magnesia and lime have increased
considerably as compared with those in the syenite. A
still more basic type occurs in irregular masses at the
contact. In Yogo Peak then we have an intrusive stock of
oval form, which shows a progressive differentiation from
east to west along its major axis. It may be remarked that,
as the several associated rock-types are composed in general
of the same minerals, the augite in particular running
through all the varieties, the differentiation seems to have
been of a kind which has elsewhere been considered to
have been effected concurrently with, and as a consequence
of, crystallisation. Another interesting point is the occurrence
of shonkinite in association with two distinct types of syenite,
the sodalite-syenite of Square Butte and the augite-syenite
of Yogo Peak ; illustrating the fact that a given rock-
type may originate by differentiation in more than one way.
A series of specimens, chiefly from intrusive sheets, in
the southern part of the same state have been described by
Merrill (13), and some of them show evident affinities with
the foregoing rocks. One type, described in several
examples under the name augite-porphyrite, compares
rather closely in chemical composition with the yogoite of

PETROLOGY IN AMERICA. 469

Weed and Pirsson, and seems to be the porphyritic or
"dyke" equivalent of that plutonic rock. A rock with
porphyritically developed olivine and augite has a peculiar
composition. With 47 per cent, of silica it has as much as
21 per cent, of magnesia, and on the other hand 3 per
cent, of alkalies, chiefly potash. Iddings has remarked that
this rock falls under the type which he has named absarokite.
The same remark applies to others from South Boulder,
Antelope, and Cottonwood Creeks, which Merrill has
described under the title of lamprophyres. These contain
mica as well as olivine and augite, but, as before, no por-
phyritic felspar, while the analyses show that the felspar
of the ground-mass is largely of a potash-bearing species.

In his Origin of Igneous Rocks (1892), Iddings drew
attention to certain dykes and lava-flows of exceptional
character occurring in the Absaroka Range in the Yellow-
stone Park region. These rocks belong to a late stage in
the igneous activity of the district. While showing evident
consanguinity with the more usual types with which they
are associated, they have chemical and mineralogical
peculiarities comparable with those of Merrill's rocks in the
country farther north. In a later paper Iddings (14) has
given a more complete account of these rocks, which con-
stitute what Brogger styles a "rock-series," that is, a num-
ber of types representing like phases of differentiation from
what may be regarded as the more normal series of basalts
and andesites, with which they are associated. Iddings
distinguishes three types, absarokite, shoshonite and bana-
kite. They are usually porphyritic, the phenocrysts being
of olivine and augite, with labradorite in the two latter
types. The ground-mass is rich in alkali-felspars, and in
some varieties contains leucite. In absarokite, which is the
most basic type with 46 to 52 per cent, of silica, there is no
porphyritic labradorite but only olivine and augite. In
shoshonite, with a silica-percentage of 50 to 60, and com-
paratively rich in alkalies, labradorite figures among the
porphyritic elements, and in banakite it predominates. In
this type mica partly takes the place of augite in the ground-
mass, and the rocks are highly felspathic. Silica ranges

470 SCIENCE PROGRESS.

from 51 to 61 per cent., and the alkalies jointly from SJ to
10 per cent, potash predominating. The most acid bana-
kites carry a certain amount of quartz. We have thus a
well-defined series of rocks which may be roughly described
as alkali-basalts and alkali-andesites.

Passing southward we have next to notice another area
of rocks rich in alkalies. Just as the Geological Survey of
Arkansas gave us a valuable account of nepheline-bearing
and allied rocks in that State, so the Texas Survey has
discovered the existence of an extensive development of
such rocks in Southern and Western Texas. Kemp in 1890
recorded a Cretaceous nepheline-basalt from Pilot Knob,
near Austin, and since then a number of interesting- rocks
have been described by Osann. Three years ago he drew
attention to two types occurring in Uvalde County in the
southern part of the state (15). One, forming dykes, is a
fresh rock named melilite-nepheline-basalt, the two minerals
being present in about equal quantity. There are large
crystals of olivine, and the ground-mass consists of augite,
nepheline, melilite, magnetite, and perofskite. The other
type, forming hills and buttes, is a nepheline-basanite, in
which the porphyritic elements are hornblende, augite and
nepheline, with some felspar and olivine. Since part of
the felspar is a sanidine, and olivine is rare, the rocks
approach phonolite in characters.

More recently the same geologist has described a varied
group of rocks, plutonic, intrusive and volcanic, in and
around the Apache Mountains in the western (trans-Pecos)
portion of Texas (16). An elaeolite-syenite occurs at
Paisana Pass, and another in the Mount Ord Range, to
the south-east of the Apaches. In both lavenite is a con-
stant accessory mineral. The Mount Ord rock passes from
a normal elaeolite-syenite through a fine-grained porphyritic
variety to a marginal phonolitic facies. The change of
texture and structure is accompanied by mineralogical
changes, the malacolite-like augite, hornblende, and mica
giving place to aegirine-augite, aegirine, arfvedsonite, and
aenigmatite. In the Saw-Tooth Mountains, in the western
part of the district, occurs an augite-hornblende-syenite,

PETROLOGY IN AMERICA. 471

without elaeolite, and this too passes at its margin into
porphyritic varieties with fine-textured ground-mass. The
special interest of these latter is that they are rhomb-
porphyries, reproducing in the peculiar habit of their por-
phyritic felspars and in other respects the characteristics of
the well-known rocks of the Christiania district. As in
other districts of elaeolite-syenites and augite-syenites, there
are in the Apache Mountains region numerous dykes of
tinguaite and bostonite, and to these two types Osann adds
a third, more acid, to which he gives the name paisanite.
This contains quartz, and has some resemblance to the
grorudite of Brogger, but differs from it in having the soda-
amphibole riebeckite instead of segirine. Moreover this
mineral occurs not in crystals but in fibrous and irregular
patches in the ground-mass, a common character in the
soda-bearing amphiboles of the whole group of rocks. The
lava-flows of the district, besides basalt and rhyolite, include
a type of phonolite which is distinguished by the name
apachite. Its special characters are firstly the abundance of
amphiboles in addition to augite and segirine, and secondly
the prevalence of microperthitic intergrowths in the felspars
of the ground-mass. The amphibole minerals are a brown
variety, apparently between arfvedsonite and barkevicite,
and a blue one resembling that which Brogger has described
in his grorudite dykes under the name cataforite. The age
of these various eruptive rocks in Western Texas has
not been determined further than that they are post-
Carboniferous.

Before leaving the subject of nepheline or elaeolite-
syenites, we may note a new Canadian occurrence recently
described by Adams (17). It occupies a large area among
the Laurentian rocks at Dungannon, Ontario. Nepheline
is by far the most abundant constituent, and one variety of
the rock is composed almost wholly of this mineral with a
little hornblende or mica, thus corresponding with the ijolite
of Ramsay and Berghell from Finland. The felspathic
constituent of the rock is albite to the exclusion of ortho-
clase, as in the occurrence at Litchfield, Maine, which
Bayley has styled litchtieldite. The other minerals present

472 SCIENCE PROGRESS.

are either mica or hornblende in different examples, scapo-
lite, calcite, a titaniferous garnet, and zircon, with sometimes
sodalite, the last occurring in places in large masses. In
the latter veins of orthoclase occur with the relations of a
secondary product (18). The rock contains a variety of
hornblende with very low axial angle. This yielded on
analysis only 34 per cent, of silica, while the alkalies
amounted to 5^ per cent.

Rocks of this class are now known from a number of
localities in Canada and the north-eastern United States,
including Montreal, where the rocks are proved to be of
Silurian age, Litchfield in Maine, Salem and Marblehead
in Massachusetts, Beemerville in New Jersey, and Red
Hill in New Hampshire. Special interest attaches to the
numerous dykes within this large region, which are either
known or inferred to stand in genetic relationship with the
elseolite syenites. These rocks include on the one hand the
highly felspathic type bostonite, and on the other hand the
complementary products of differentiation represented by
camptonite, monchiquite, ouachitite, fourchite, and other
peculiar lamprophyric rocks. Rosenbusch founded his
type camptonite on Hawes' rock from Campton Falls in
New Hampshire. Other examples have been described by
Harrington from Montreal, by Kemp and Marsters from
the Forest of Dean in New York State, the Hudson River
highlands, Whitehall also in New York, etc. From Andro
scoggin County, Maine, Merrill (19) has described rocks
which might be termed augite-camptonites, containing that
mineral both in phenocrysts and in the ground-mass, as
well as hornblende, but showing a tendency towards the
ophitic structure which places them in an intermediate
position between the lamprophyres and the diabases.

The elseolite-syenite of Beemerville was first recognised
as such by Emerson, but Kemp (20) has added consider-
able information relative to its modifications and its atten-
dant dykes. A porphyritic marginal facies of the main
mass is of special interest since Brogger has taken it as
the type of his sussexite, the basic end-member of his
grorudite-solvsbergite-tinguaite series. It contains 45 per

PETROLOGY IN AMERICA. 473

cent, of silica and 1 1 per cent, of soda, and consists of
porphyritic crystals of nepheline up to an inch in diameter
in a tinguaitic ground-mass rich in nepheline and aegirine.
The associated basic dykes in this district are mostly rich in
biotite, corresponding with the ouachitite of Arkansas and
in some cases with the allied type fourchite.

The dykes of the Lake Champlain district in New
York and Vermont were noticed by Kemp and Marsters
in 1 89 1, and more recently a Bulletin of the National
Geological Survey has given a fuller account by the
same writers (21). Besides bostonites and diabases, they
describe typical camptonites with hornblende, augite-camp-
tonites, monchiquites, and other rocks which from the
absence of olivine are placed under fourchite. Near Danby-
borough in Vermont, Marsters (22) has described a variety
of camptonite differing from the Campton type in having
no porphyritic hornblende. This mineral occurs in idio-
morphic brown crystals in the ground-mass, while there are
also two generations of augite and rather abundant biotite.
From Lake Memphremagog, on the Canadian border of
the same state, he has recorded (23) a number of lampro-
phyre dykes associated with dykes of granite, occasionally
taking on the characters of bostonite. The prevalent type
here is an augite-camptonite, in which both augite and horn-
blende occur in two generations. Hornblende -camptonite,
monchiquite, and fourchite are represented by single dykes.

These various rocks, as will be noticed, do not contain
any mineral of the " felspathoid " group (leucite, nepheline,
sodalite, etc.). Kemp (24) has, however, drawn attention
to a peculiar dyke occurring at Hamburg, N.J., at some
distance from the Beemerville elaeolite-syenite, and present-
ing mineralogically some resemblance to the rather ill-
defined group of rocks named teschenites. The rock in
question consists nainly of biotite and pyroxene set in an
interstitial mass of analcime. It contains spheroidal bodies
up to 10 mm. in diameter composed of analcime. apparently
pseudomorphs after some vanished mineral. Hussak in
1892 had already taken these as indicating destroyed leucite,
and Kemp has subsequently placed this beyond doubt by

474 SCIENCE PROGRESS.

finding fresher specimens in which some leucite still re-
mains.

The presence of melilite in certain dykes in the region
is another point of interest. Smyth in 1892 described a
rock from Manheim, N.Y., under the name peridotite, as
consisting of abundant olivine, biotite, magnetite, and
perofskite, with considerable quantities of alteration-pro-
ducts. Later study of fresher material has enabled him to
identify melilite as a constituent, and the rock becomes an
alnoite or melilite-basalt (25). The melilite shows the char-
acteristic "peg-structure," but differs optically from the
mineral as usually known in having positive double re-
fraction. An alnoite had already been described by Adams
from Ste Anne de Bellevue near Montreal (26). Here the
porphyritic elements are large crystals of brown mica
(anomite), olivine (with conversion to haematite), and augite,
and the ground-mass consists of the same minerals with
melilite, magnetite, apatite, and perofskite, the rock agreeing
very closely with that of Alno, off the coast of Sweden.

Some other porphyritic dyke-rocks which have been
called peridotites might perhaps be placed with more
propriety under monchiquite as olivine-bearing lampro-
phyres. Darton and Kemp (27) have described such a
rock from De Witt, near Syracuse, in the same district as
the Manheim alnoite. It contains abundant olivine and
porphyritic crystals of biotite and subordinate augite in an
augitic ground-mass of the monchiquite type. The peri-
dotite of Pike County, Arkansas, seems to be closely similar.
Of the monchiquites and the typical fourchites and ouachit-
ites of the last-named state it is not necessary to speak —
we have referred to the work of the late J. F. Williams on
a former occasion. Here, as elsewhere, these peculiar
lamprophyre dykes figure as the satellites of plutonic rocks
of the nepheline-syenite family, though some occur at
considerable distances from any visible outcrop of the
latter rocks. These Arkansas intrusions are assigned to an
epoch about the close of the Cretaceous period.

We pass westward in our hasty survey to the Rocky
Mountain region. Limitations of space compel us to omit

PETROLOGY IN AMERICA. 475

in the present communication any notice of the varied series
of Tertiary effusive rocks, as we have already passed over
the equally interesting ancient lavas and tuffs of the eastern
states ; and we go on to notice an important memoir by
Whitman Cross (28) on a widely distributed type of in-
trusive rock. It was about twenty years ago that Peale,
Holmes, and Gilbert investigated the nature of the large
lenticular masses of igneous rocks which occur in various
parts of the Rocky Mountains of Colorado, and have given
rise to numerous isolated groups of mountains farther west,
in Utah and Arizona. To intrusions of this form, uplifting
the strata above them in the fashion of a dome, Gilbert
gave the name laccolite, and the highly symmetrical
examples described by him in the Henry Mountains in
Utah have remained the type of this kind of occurrence.
But little petrographical examination was made at that
time of the rocks constituting these laccolites, which were
generally referred to as trachytes. In 1887 Cross pointed
out that this name was not well chosen, and that trachyte
in the strict sense is certainly not a common rock-type in
the region. In his recent paper, besides adding consider-
ably to our knowledge of the nature of these laccolitic
intrusions and the varieties of form which they take on in
different circumstances, he has given a very complete
account of the rocks which compose them. The most
striking feature of these rocks is their uniformity in chemi-
cal, mineralogical, and structural characters throughout a
very extensive tract, prolonged northward apparently into
the Yellowstone Park and perhaps into Montana. The
analyses show variation between certain limits in silica-
percentage and in some other particulars with a remarkable
constancy in certain other features. The alkalies jointly
are always about 6 or 7 per cent., potash and soda being in
equal quantities in the rocks of Colorado, while the latter
preponderates in those of the plateau groups to the west
and in the Yellowstone district. All, or nearly all, the
rocks are porphyritic, crystals of plagioclase felspar and
ferro-magnesian silicates having been formed prior to the
intrusion of the magma. Plagioclase is predominant and,

476 SCIENCE PROGRESS.

of the dark silicates, hornblende and biotite, hypersthene
and augite, appearing only locally. Quartz also occurs, and
in some cases very large crystals of orthoclase. The por-
phyritic elements have continued to grow after the intrusion,
and the large orthoclase crystals belong wholly to this stage
of the consolidation : the author dissents from the view
that phenocrysts are always to be regarded as representing
the first or intratelluric period of crystallisation and the
ground-mass the second period. In these rocks the ground-
mass is of very constant characters, being essentially a
granular aggregate of orthoclase and quartz. The several
varieties may be grouped generally as porphyrites, usually
hornblende-porphyrite, in some cases quartz-porphyrite.

In conclusion we shall briefly notice some of the petro-
graphical memoirs issued as bulletins from the laboratory
of the University of California, which, under the direction
of Lawson is producing some very useful work in the far
West. The first instalment, by the Professor himself (29),
deals with the geology of Carmelo Bay, some distance
south of San Francisco. The chief interest, from a peno-
logical point of view, centres in the eruptive rocks to which
Lawson has given the name carmeloite. These exhibit
variations of characters within certain limits, the silica per-
centage ranging at least from 52 to 60, so that the rocks hold
in some respects a position intermediate between basalt and
andesite. They have in some cases porphyritic augite and
plagioclase, and the ground-mass varies from a holocrystal-
line one to one rich in glass. The special feature, however,
is the presence of crystals of a mineral for which the name
iddingsite is proposed. This substance occurs in crystal
forms like those of olivine, with a lamellar structure due to
a very perfect cleavage, and with a bronzy lustre on the
cleavage faces. Optical examination proves the rhombic
symmetry of the mineral, and reveals a brown colour with
strong pleochroism. Qualitative chemical tests prove it to
be a hydrous non-aluminous silicate of iron, lime, magnesia
and soda. The characterisation of carmeloite by reference
to this mineral seems to imply that the latter is, as Lawson
inclines to believe, an original constituent of the rock, and

PETROLOGY IN AMERICA. 477

not a pseudomorph after olivine. Without prejudging this
question, it may be remarked that numerous British basalts
and diabases contain a mineral agreeing pretty closely with
the description of iddingsite, but undoubtedly derived by
alteration from olivine, unchanged relics of which sometimes
remain in the heart of the pseudomorph.

Palache (30) has described a rock occurring as a lava-
flow of late Cretaceous or probably early Tertiary age in
the Contra Costa hills, north of Berkeley. It is an acid
lava in which soda preponderates largely over potash, and
it is accordingly styled soda-rhyolite. It shows gradations
from a porphyritic variety with microcrystalline ground-
mass to a pure glass, the bulk of the flow having a
microspherulitic structure. One variety consists largely of
spheroidal bodies up to three inches in diameter, hollow
and containing chalcedony, etc. : these are probably altered
large spherulites, and the author's account of them reminds
us of those so frequently met with in the ancient rhyolitic
lavas of North Wales and other districts.

The same geologist has investigated a blue soda-
amphibole which seems to have a wide distribution among
the crystalline schists of the Coast Ranges of California
(31). The rock in which the mineral was specially studied
consists of this mineral and albite. The mineral has the
usual crystallographic habit and cleavages of a hornblende.
It is strongly pleochroic in blue, violet, and yellowish-brown
colours, and its extinction-angle is about 130. It bears a
considerable resemblance to riebeckite, and a chemical
analysis places it between that mineral and glaucophane.
The author names the new variety crossite, as apparently
identical with a blue amphibole described by Whitman
Cross in Custer County, Colorado, and one more soda-
bearing amphibole is thus added to the number already
recognised.

Another new rock-forming mineral has been described
by Ransome and Palache (32, ^7,) from the Tiburon Penin-
sula, north of San Francisco, where it forms an important
constituent of a particular crystalline schist. It has been
found also in glaucophane-schists near Berkeley and else-

478 SCIENCE PROGRESS.

where, and may prove to have a more extended distribution.
It is a rhombic mineral with simple crystallographic habit
and two conspicuous cleavages, and it has a blue colour
with strong pleochroism, which, however, is lost in ordinary
thin slices. The specific gravity is 3*08, and the composi-
tion is expressed by the formula H4Ca Al2 Si20IO, suggest-
ing" a comparison with the manganese mineral carpholite.
To the new mineral the name lawsonite is given. It is
associated in the rock with margarite, epidote, actinolite,
glaucophane, and garnet. The glaucophane is peculiar as
having an extinction-angle of 130 to 150, much higher than
in the normal mineral and perhaps indicating an admixture
of the actinolite-molecule.

A very instructive memoir by Ransome deals with the
geology of Angel Island in San Francisco Bay (34). This
island consists mainly of the (probably Cretaceous) San
Francisco Sandstone, with intercalated beds of radiolarian
chert ; but intruded into these are sills of a rock which is
doubtfully placed with fourchite, and also a large dyke of
serpentine derived from what has been essentially a diallage-
rock. The so-called fourchite is composed mainly of augite,
not in crystals but in granules of two sizes, with a matrix
consisting of an aggregate of minute prisms of some colour-
less mineral. The latter is referred to zoisite, and is
certainly secondary, possibly derived from felspar. There
are varieties of the rock which contain little plagioclase
prisms, and in particular a spheroidal variety in which the
felspar occurs in skeletons, delicate needles, and brush-like
groupings. The typical fourchite of Williams, it should be
remarked, contains no felspar. The chief feature of interest,
however, is the metamorphism produced by the intrusive
masses in the bedded rocks, which are converted near the
junction into glaucophane-schists. One of these, where the
sandstone borders the main sill of fourchite, consists chiefly
of glaucophane, albite, and biotite in varying proportions.
In other specimens quartz is the chief constituent. The
radiolarian cherts are changed into a rock composed of
quartz with needles of glaucophane, actinolite, etc., and in
less altered examples blue glaucophane needles have been

PETROLOGY IN AMERICA. 479

developed while the outlines of the radiolaria are still
recognisable. Glaucophane-schist has also been produced
at the contact of the sandstone with the serpentine. The
blue amphibole mineral in these various rocks seems to be
in general true glaucophane, though it is possible that
crossite or other varieties may also occur. These observa-
tions are evidently of importance with reference to the
origin of the glaucophane-schists in general of California,
and perhaps of other districts. Lawson has expressed a
confident opinion that all the glaucophane-, hornblende-, and
mica-schists in the Coast Ranges are products of contact-
metamorphism by basic eruptive rocks.

Some other points in the geology of Angel Island are
of interest in connection with an earlier paper by the same
author upon the eruptive rocks of Bonita Point, the northerly
horn of San Francisco Bay (35). The strata here still
belong to the San Francisco Sandstone, and include beds
of "red jasper" corresponding with the radiolarian cherts
mentioned above. The chief igneous rock is a basalt with
what is for convenience called a spheroidal structure. The
distinct portions into which the mass divides are, however,
not spheroids but rather bale-like and pillow-like bodies,
which give the effect of having been squeezed against one
another while in a plastic state, a description which would
apply to part of the " fourchite " of Angel Island and to
some " spheroidal " basalts and diabases in other regions.
The author expresses the opinion that the rock was poured
out as a somewhat viscous lava (the viscosity being ascribed
to the 2 or 3 per cent, of titanic acid present), successive
sluggish out-pourings being piled upon one another,
becoming sometimes spheroidal by rolling and sometimes
lenticular by flattening. In addition to the basalt, there is
at Bonita Point an intrusive diabase containing iddingsite,
which Ransome regards as probably a pseudomorph after
olivine. This has in piaces a spheroidal structure of a
somewhat different kind attributed to a kind of rlow-breccia-
tion. The "fourchite" of r\ngel Island shows in one
intrusion a spheroidal structure allied to brecciation, and in
another the peculiar structure described in the basalt. The

480 SCIENCE PROGRESS.

author is thus brought to the conclusion that this feature is
not restricted to surface-flows, but he believes that rocks
exhibiting it must have been erupted under very nearly
surface condition. This is to some extent in accordance
with the opinion expressed by Fox and Teall with respect
to the dolerite associated with the radiolarian chert of
Mullion Island, Cornwall. This rock, " separated into rude
rolls by curvilinear joints," they suggest may represent a
submarine flow injected between the layers of the stratified
series near the sea-bed during deposition. The associa-
tion of these curious spheroidal rocks with radiolarian cherts
at a number of localities in California and elsewhere seems
significant, but the mechanism of igneous eruptions under
a great pressure of water is a subject upon which it would
not be safe to speculate at present.

We have already noted Ransome's account of the
serpentine of Angel Island, which is demonstrated to be a
decomposed diallage-rock. Palache (37) has described the
serpentine of the Potrero, San Francisco, which is also of
igneous origin and intrusive in the sandstones. In this
case the rock has been derived from one consisting of
olivine, enstatite, diallage, chromite, and magnetite, and so
belonging to the lherzolite type. Lawson finds serpentine
rocks in other parts of the district to be in all cases derived
from igneous rocks, peridotites or pyroxenites.

The work embodied in the various memoirs which we
have cited has q-one far towards removing some serious
difficulties felt by many readers with reference to the
geology of the Pacific Slope as interpreted in Becker's
monograph on the Quicksilver Deposits (1888). The San
Francisco Sandstone and its associated rocks correspond
with the Knoxville group of that writer, who endeavoured
to explain the characters of many of these rocks by various
obscure processes of metamorphism operating upon sedi-
mentary deposits. The bedded jaspers are now proved to
be not silicified shales, but original siliceous deposits, largely
due to radiolaria, though Lawson believes much of the
silica to have been chemically precipitated. The "pseudo-
diabases " and " pseudodiorites " of Becker, formerly stated

PETROLOGY IN AMERICA. 481

to be metamorphosed sediments, are all recognised as true
igneous rocks, either contemporaneous or intrusive ; and
the serpentines, instead of arising from the metamorphism
of various sedimentary rocks, are found here, as in other
countries, to be decomposed basic and ultrabasic eruptives.
Of the formidable series of supposed metamorphic rocks
described in Monograph XIII. there remain only the
glaucophane-bearing and other crystalline schists, and these
seem to be in all cases contact-zones bordering intrusions of
basic rocks (36).

BIBLIOGRAPHY.

(i) Adams, Frank D. Ueber das Norian oder Ober-Laurentian
von Canada. Neu. Jahrb. fur Mm., Beil. Bd. viii., pp.
419-498, 1893.

{2) Lawson, Andrew, C. The Anorthosytes of the Minnesota
Shore of Lake Superior. Bull. No. 8 of Geol. and Nat. Hist.
Surv. Minn., pp. 1-23, 1893.

{3) BAYLEY, W. S. The Basic Massive Rocks of the Lake
Superior Region, four, of Geol., vol. i, pp. 433-456, 587-
596, 688-716; vol. ii., pp. 814-825; vol. iii., pp. 1-20,

I893-5-
{4) KEMP, J. F. Gabbros of the Western Shore of Lake

Champlain. Bull. Geol. Soc. Atner., vol. v., pp. 213-224,

1894.

(5) Kemp, James Furman. The Geology of Moriah and West-

port Townships, Essex County, N.Y. Bull. N. Y. State
Mus., vol. iii., No. 14, pp. 325-355. i§95-

(6) Smyth, C. H., Jr. Crystalline Limestones and Associated

Rocks of the North-western Adirondack Region. Bull. Geol.
Soc. Amer., vol. vi., pp. 263-284, 1895.

(7) BAYLEY, W. S. A Fibrous Intergrowth of Augite and

Plagioclase resembling a Reaction Rim in a Minnesota
Gabbro. Amer. fourn. Sci. (3), vol. xliii., pp. 515-520,
1892.

(8) Kemp, J. F. The Nickel Mine at Lancaster Gap, Penn-

sylvania and the Pyrrhotite Deposits at Anthony's Nose
on the Hudson. Trans. Amer. Inst. Mining Engin., 14 pp.
1894.

(9) Kemp, J. F. Crystalline Limestones, Ophicalcites and

Associated Schists of the Eastern Adirondacks. Bull. Geol.
Soc. Amer., vol. vi., pp. 241-262, 1895.

34

482 SCIENCE PROGRESS.

(10) PlRSSON, L. V. On some Phonolitic Rocks from Montana.

Amer. Jour. Sci. (3), vol. 1., pp. 394-399, 1895.
Weed, Walter Harvey. Phonolitic Rocks from Montana.
Ibid., pp. 506, 507.

(11) Weed, Walter H. and Pirsson, Louis V. Highwood

Mountains of Montana. Bull. Geol. Soc. Amer., vol. vi., pp.
389-422, 1895.
Lindgren, W. A Sodalite-Syenite and other Rocks from
Montana. Amer. Journ. Sci. (3), vol. xlv., pp. 286-297, 1893.

(12) Weed, W. H. and PlRSSON, L. V. Igneous Rocks of Yogo

Peak, Montana. Amer. Journ. Sci. (3), vol. 1., pp. 467-479,

1895.

(13) Merrill, George P. Notes on some Eruptive Rocks from

Gallatin, Jefferson, and Madison Counties, Montana. Proc.
U.S. Nat. Mus., vol. xvii., pp. 6^7-67^, 1895. Review by
Iddings. Journ. of Geol., vol. hi., pp. 850, 851, 1895.

(14) IDDINGS, JOSEPH P. Absarokite-Shoshonite-Banakite Series.

Journ. of Geol., vol. hi., pp. 935-959, 1895.

(15) Osann,A. Melilite-Nepheline-Rasalt and Nepheline-Basanite

from Southern Texas. Ibid., vol. i., pp. 341-346, 1893.

(16) OSANN, A. Beitrage zur Geologie und Petrographie der

Apache (Davis) Mountains, West Texas. Tscherm. Min. u.
Petr. Mitth., vol. xv., pp. 394-456, 1886.

(17) Adams, Frank D. On the occurrence of a large area of

Nepheline Syenite in the Township of Dungannon, Ontario.
Amer. Journ. Sci. (3), vol. xlviii., pp. 10-16, 1894.

(18) HARRINGTON, B. J. On Nepheline, Sodalite and Orthoclase

from the Nepheline Syenite of Dungannon, Hastings County,
Ontario. Ibid., pp. 16-18.
Adams, Frank D., and Harrington, B. J. On a New
Alkali Hornblende and a Titaniferous Andradite from the
Nepheline-Syenite of Dungannon, Hastings County, Ontario.
Ibid. (4), vol. i., 210-218, 1896.

(19) Merrill, George P. On some Basic Eruptive Rocks in

the vicinity of Lewiston and Auburn, Androscoggin County,
Maine. Amer. Geol., vol. x., pp. 49-55, 1892.

(20) Kemp, J. F. The Elaeolite Syenite near Beemerville, Sussex

County, New Jersey. Trans. N. Y. Acad. Sci., vol. xi., pp.
60-72, 1892.

(21) Kemp, James Furman, and Marsters, Vernon Freeman.

The Trap Dikes of the Lake Champlain region. Bull. No.
107 of U.S. Geol. Surv., 1893.

(22) Marsters, Vernon F. Camptonite Dykes near Danby-

borough, Vt. Amer. Geol., vol. xv., pp. 368-371, 1895.

PETROLOGY IN AMERICA. 483

Marsters, Vernon F. Camptonites and other Intrusives

of Lake Memphremagog. Ibid., vol. xvi., pp. 25-39, 1895.
KEMP, J. F. A Basic Dike near Hamburg, Sussex County,

New Jersey, which has been thought to contain Leucite.

Amer. Journ. Sci. (3) vol. xlv., pp. 298-305, 1893.
Kemp, J. F. Additional Note on Leucite in Sussex County,

New Jersey. Ibid., vol. xlvii., pp. 339-340, 1894.
SMYTH, C. H., Jr. AlnSite containing an uncommon Variety

of Melilite. Ibid., vol. xlvi., pp. 104-107.
Adams, Frank D. On a Melilite-bearing Rock (AlnSite)

from Ste Anne de Bellevue near Montreal, Canana. Ibid.,

vol. xliii., pp. 269-279, 1892.
Darton, N. H., and Kemp, J. F. A Newly Discovered

Dike at De Witt, near Syracuse, New York. Amer. Journ.

Sci. (3), vol. xlix., pp. 456-462, 1895.
Cross, Whitman. The Laccolitic Mountain Groups of

Colorado, Utah and Arizona. 14//2 Ann. Rep. U.S. Geo/.

Surv., pp. 157-241, 1895.
Lawson, Andrew C. The Geology of Carmelo Bay. Bull.

Dep. ofGeol., Univ. of Calif., No. 1., vol. i., pp. 1-59, 1893.
PALACHE, Charles. The Soda-Rhyolite north of Berkeley.

Ibid., No. 2, vol. i., pp. 61-72, 1893.
PALACHE, Charles. On a Rock from the Vicinity of

Berkeley containing a New Soda Amphibole. Ibid., No. 6,

vol. i., pp. 181-192, 1894.
RANSOME, F. Leslie. On Lawsonite, a New Rock-Forming

Mineral, from the Tiburon Peninsula, Marin County., Cal.

Ibid., No. 10, vol. i., pp. 301-312, 1895.
RANSOME, F. L., and PALACHE, Ch. Ueber Lawsonit, ein

neues gesteinbildendes Mineral aus Californien. Zeits. fur

Kryst., vol. xxv., pp. 531-537, 1896.
RANSOME, F. Leslie. The Geology of Angel Island. Bull.

Dep. of Geo!., Univ. of Calif., No. 7, vol. i., pp. 193-240,

1894.
RANSOME, F. Leslie. The Eruptive Rocks of Point Bonita.

Ibid., No. 3, vol. i., pp. 7I"II4, l893.
Lawson, Andrew C. A Contribution to the Geology of

the Coast Ranges. Amer. Geol., vol. xv., pp. 342-356,

1895.
PALACHE, CHARLES. The Lherzolite-Serpentine and Associ-
ated Rocks of the Potrero, San Francisco. Bull. Dep. of

Geol., Univ. of Calif , No. 5, vol. i., pp. 161-192, 1894.

Alfred Harker.

GOLD EXTRACTION PROCESSES.

FROM very early times the ancients were attracted by
the beautiful colour, the brilliant lustre, and the
indestructibility of gold, and spared no pains in the en-
deavour to acquire it. In the code of Menes, who
reigned in Egypt some 2000 years before the time of
Moses, the ratio of value between gold and silver is
mentioned, one part of gold being declared equal in value
to two and a half parts of silver, and it is, therefore, clear
that the extraction of both metals from the deposits con-
taining them must have been carried on before that time.
It is indeed probable that gold was the first metal observed
and collected, since it occurs in fragments of all sizes in
loose sand, and the operations of collecting the larger pieces
and melting them together are so simple. Among the rock
carvings of Upper Egypt there are several illustrative of
the art of washing auriferous sands by stirring and working
them up by the hand in hollowed-out stone basins, and
subsequently melting the gold in simple furnaces with the
aid of mouth blow-pipes. The earliest of these carvings is
supposed to date back to about 2500 B.C. However, in
ancient times gold appears to have been mainly derived
from India, and that country continued to supply most of
the gold used in Europe until the discovery of America by
Columbus.

In order to collect alluvial gold, the sands were
washed down over smooth sloping rocks by means of
running water, and the particles of gold sinking to the
bottom of the stream by reason of their high density, were
entangled and caught by the hair on raw hides spread on
the rocks. Among the hides used were sheepskins, and
hence originated the form of the legend of the Golden
Fleece. Stripped of its heroic dress this legend of course
describes a piratical expedition to win gold which was
being obtained from streams with the help of sheepskins
by the inhabitants of what is now Armenia. Similar

GOLD EXTRACTION PROCESSES. 485

expeditions have not been unknown in much later times,
and the method of obtaining gold by washing river sands
is still practised with improvements in matters of detail in
many parts of the world. Hides are even now occasionally
employed to catch the gold, but sheepswool when used is
generally in the form of blankets.

The use of mercury as an aid in the collection of gold
contained in river sands or in crushed rock is also of great
antiquity. The earliest mention of quicksilver itself appears
to occur in the works of Theophrastus, about B.C. 300; but
Diodorus of Sicily, who saw gold being extracted from
quartz in Upper Egypt in the time of Julius Csesar does
not refer to its use.1 Only a few years later, however,
Vitruvius,2 about B.C. 13, described the manner in which,
by the help of quicksilver, gold was recovered from cloth
in which it had been interwoven, and in Pliny's time the
separation of gold from its impurities generally by the
same means was well known.3 It is probable that this
knowledge was never afterwards entirely lost, although the
references to it in the Middle Ages are very scanty. For
example Geber4 in the eighth century was aware that
mercury would dissolve considerable quantities of gold and
silver, but not earthy materials, and Theophilus the monk,5
in the eleventh century carefully described the method of
washing the sands of the Rhine on wooden tables, the
final operation consisting in treating the concentrates with
quicksilver for the removal of the gold. Biringuccio6 was
taught the secret of this use of mercury in Italy some time
before 1540 in return for the present of a valuable diamond
ring, and it is clear that the so-called invention of the
amalgamation process in Mexico by the Spaniards in 1557

1 Diodor., iii., 13. A full translation is given by B. H. Brough in his
Cantor lectures on Mine Surveying. Juur. Soc. Arts, 1892.
2Vit. lib., vii., cap. 8.

3 Nat. Hist., lib. xxx., cap. vi., sect 32. Quoted in full in Percy's
Metallurgy of Silver and Gold, p. 559.

4 Salmon's Geber, cap. 47. 5 Theophili, lib. iii., cap. 49.
6 De la Pirotechnia. Venetia, 1540. Lib. ix., cap. xi., fol. 142.

486 SCIENCE PROGRESS.

was only the introduction or adaptation of a process already
well known in Europe.

The existing methods of washing auriferous sands all
depend on two principles, the great density of gold when
compared with that of the siliceous material with which it
is associated, and, as Baron Born expressed it over ioo
years ago, the " elective affinity" of mercury for gold when
mixed with impurities. The ease with which gold-amalgam
can be collected in spite of its being less dense than gold is
of course due to the fact that it is miscible in all proportions
with mercury, so that under proper conditions large
globules of liquid alloy are formed by the running-to-
gether of smaller particles, and the former are readily
caught in suitable crevices.

A large number of implements of varied form and
efficiency are used in different parts of the world to apply
these principles. In operations on a small scale the batea,
the trough, and the miner's pan are chiefly used. In South
America, in West Africa, and in parts of China, the batea is
used, a wooden vessel having the shape of a very short
reversed cone. When held in the hands and filled with
gravel and water, a peculiar gyratory motion imparted to it
results in the collection of the gold in the apex of the
cone, and the light material can then be readily washed
away.

A small wooden trough, twelve or fifteen inches long, is
used for the same purpose in the far East by the Chinese,
the Tonquins, the Annamites, the Malays, and others, the
water being made to flow up and down until the gold has
settled to the bottom. The miner's pan, a flat-bottomed
iron vessel with sloping sides, was first used by the
Californian pioneers, but has now become the favourite
implement of Europeans for prospecting in all parts of the
world. In early days in Australia and California millions
of ounces of gold were obtained from the river gravels
by its use, but apart from its value in prospecting it is
at most a rough and ready means of treating small
quantities of rich material, and is only suitable to individual
effort.

GOLD EXTRACTION PROCESSES. 487

In combined efforts to treat larger quantities of sand,
the machines all consist essentially of a slightly inclined
trough, through which a stream of water is made to convey
the auriferous sand, mercury being usually sprinkled on at
short intervals of time. If the trough is long enough, and
the stream of water not too rapid, the gold and mercury
sink, and, uniting, are swept along together, until arrested
by some inequality of the bottom.

Crevices and "riffles" or obstructions of various kinds
are arranged to catch the amalgam. The simplest con-
trivances are transverse slats of wood nailed to the bottom
of the trough or sluice. In Siberia square " pigeon-hole "
depressions have been continuously used for more that
fifty years. In California, the sluice is paved with square
blocks of wood placed an inch or more apart, or with large
rounded stones, or ordinary iron rails between which are
plenty of crevices where the amalgam can lodge. To catch
light spangles of gold, blankets are spread, the loose fibres
of which become charged with pyrites and gold, and in New
Zealand, plush is a favourite gold catcher.

When a "clean-up" is desired, a stream of clear water is
run through the sluice, the riffles are taken up, the mercury
and amalgam washed down and allowed to accumulate at
some convenient spot, and then ladled out and squeezed in
bags of canvas or leather as in the days of Pliny, who
describes the process as follows : " ut et ipsum [i.e.,
argentum vivum] ab auro discedat, in pellis subactas
effunditur, per quas sudoris vice defluens purum relinquit
aurum ". The excess of mercury being thus filtered off,
the pasty amalgam, containing about one-third of gold, is
retorted.

The methods of conveying the auriferous material to
the sluices vary with the scale of the operations and the
other conditions. When rocking cradles or the smaller
sluices are used, the gravel is shovelled into them. In Siberia,
where the valleys are shallow and the inclination of the
ground small, the gravel is carried in carts up an inclined
plane to an elevated wooden platform whence the sluice
starts. In California, where the gulches are deep, the fall

488 SCIENCE PROGRESS.

of the ground rapid, and the auriferous deposits of great
thickness, the banks of gravel are attacked by jets of
water of tremendous power, and the earth washed down
and carried through the sluices without being touched by-
hand, the so-called " hydraulic method ". When the gravel
beds are below the general level of the country they are
raised by the "hydraulic elevator," a jet of water, under
a head of as much as 400 or 500 feet, carrying water,
sand, and boulders alike up a pipe inclined at some 6o°
to the horizon, so as to deliver them all at the head of
the sluice, the vertical lift being sometimes over 40 feet.

One of the main difficulties in the hydraulic process is
in the disposal of the tailings, which are usually discharged
into a river or into the sea. The enormous amount of loose
sand and gravel, delivered from the hydraulic mines into
the Yuba and Feather rivers, California, prior to 1880,
filled up their beds to such an extent that in rainy weather
disastrous floods ensued, and much valuable agricultural
land was buried beneath sterile drift deposits and rendered
worthless. The farmers thereupon took action against
the mining companies and obtained a perpetual injunction
forbidding the discharge of tailings into these rivers.
The result has been to stop the use of the hydraulic
method in these important districts, and an apparently
irreparable blow was inflicted on gold winning industry in
California.

In every country as soon as the richest of the placer beds
have been worked out, efforts are made to extract the gold
from quartz veins. The quartz must of course be crushed, and
the crushed material has in the past been generally treated
similarly to the auriferous sands occurring naturally. Thus,
according to the account given by Diodorus Siculus already
referred to, the quartz was reduced to coarse powder by
pounding it in stone mortars, then finely ground in handmills
resembling the flour mills of the present day, and finally
washed down over inclined planks with water, when the
lighter material was carried away and the heavy gold
retained on the wood. Hollowed-out stone mortars suitable
for the first of these operations have been found in many

GOLD EXTRACTION PROCESSES. 489

parts of the world, including Wales, Central America, the
Pyrenees, and Transylvania. The stamp mill has no doubt
been evolved from the pestle and mortar, but was not used
for crushing ores until about the year 15 19 when the process
of wet stamping and sifting was introduced by Paul Grom-
mestetter in Joachimsthal, the two operations, however,
being at first kept distinct.

Agricola has given an exact description of the treatment
of auriferous quartz in Germany in 1556,1 from which it
appears that the methods in use at that time were strikingly
similar to those still employed in Transylvania and the
Tyrol, which were among the districts of which he wrote.
Doubtless in these districts the methods have been handed
down from generation to generation with little change, while
in other countries where they were introduced hundreds of
years later the changes have been rapid and striking. In
those points in which the older Tyrolean practice differed
from the modern one, it resembled the procedure of the old
Egyptians. The wooden stamps, shod with hard stone or
iron, were arranged in sets of three, and raised by cams to
fall by gravity when released. The rock was shovelled dry
into the mortar, and coarsely crushed by the blows of the
stamps.

Next it was ground as fine as flour in a stone mill sup-
plied with water, and carried by the stream of water into
the uppermost of three wooden tubs, whence it overflowed
in succession into the other two. Revolving mechanical
stirrers furnished with six paddles kept in agitation the
contents of the tubs, and "separate even very minute flakes
of gold from the crushed ore. These flakes, settling to the
bottom, are drawn to itself and cleansed by the quicksilver
(lying in the tubs), but the water carries off the dross."2
Agricola here expounds the theory of amalgamation still
adhered to in Austria, where mercury is regarded merely
as a useful means of collecting particles of gold which have
already been separated from the crushed ore by their great

1 Agricola. De Re Metallica, p. 233. Basel, 1556.

2 Agricola, loc cit.

49o SCIENCE PROGRESS.

density. The Tyrolean bowls still in use at Vorospatack in
Hungary and in a few retired valleys in the Eastern Alps
do not differ essentially from the tubs drawn and described
by Agricola ; and, although wet crushing by the stamps has
been introduced, the mortar is not usually furnished with
screens.

Elsewhere, the changes in stamp battery amalgamation
since Agricola wrote his treatise have been many and
great. One of the first was the addition of screens in the
side of the mortar, so that the two operations of crushing
and sifting were united. In 1767 M. Jars saw these in use
in the Hartz,1 though even then only a single screen of
brass wire twelve inches square delivered the product of
three stamps, and in several other districts of Germany
screens had not been adopted. The most important improve-
ment however has undoubtedly been the introduction of the
amalgamated copper plate for catching gold, the comple-
ment of the practice of charging mercury with the ore into
the battery and so combining the operations of crushing and
amalgamation. No mention of either this practice or the
use of copper plates appears to have been made before
stamp batteries began to work in California in 1850, al-
though they had very likely been used in Georgia for some
time previously.

The use of the copper plate was probably suggested by
the experience in Mexico and South America of the working
of the Cazo process, in which it was well known that
amalgam tended to adhere to the copper sides of the vessel
unless the proportion of mercury to gold and silver present
was less than four to one. Thus Baron Born wrote in
17862: "In new kettles . . . the inside becomes wholly
and so perfectly silvered that it never can be cleaned. . . .
The silvery coat is daily increased by slow and gradual
apposition, and the crusts of amalgama, accumulating on the
bottom and sides of the vessels, become gradually so thick
that on emptying them they often fall off by their own

1 Voyages Aletalhirgiques, vol. ii., p. 309. Paris, 17 So.

2 Baron Inigo Bom's New Process of Afjialgamation, p. 1 22, Translated
by Raspe. London, 1791.

GOLD EXTRACTION PROCESSES. 491

weight as silver plates, which, when dry, show the lamin-
ated texture of their daily augmentation."

The knowledge of this behaviour of amalgam in the
Cazo process must have been common to many who were
engaged in exploiting the quartz veins of the West soon
after their discovery, and the speedy application of this
knowledge is exactly what might be expected from those
sturdy pioneers. Nevertheless, the exact date and locality
of the introduction of the copper plate remains a matter for
conjecture.

The copper plates fixed on the battery in the early
fifties were about four inches wide and as long as the
mortar, and were placed one on the "feed" side and one
on the discharge side just underneath the screens. It
was soon found that the plates worked better from the
start if mercury was rubbed on them before they were
placed in position, and this has now been invariably done
for many years. Crushed ore, stones, water, and amalgam
are flung violently against the plates and the amalgam is
retained in great part.

The scouring action of the pulp on the plates is however
always great, and becomes more violent in proportion as
the stamps are larger. These are now as much as 1100
and even 1250 lbs. in weight in the Transvaal, an enormous
mass when compared with the 750 lb. stamp of a few years
ago, and the 1 20 lb. stamp of the last century. With this
increase in weight, it has become desirable to modify the use
of the copper plate. The plate on the feed side, long ago
condemned by many, is accordingly being discarded more
and more, and that below the screens is curved away in such
a manner that it cannot be struck directly by the splash
from the stamp, while slots in cast-steel plates lining the
mortar have been devised for the purpose of catching
amalgam.

After leaving the mortar the pulp was treated forty
years ago mainly by passing it over inclined tables covered
with blankets, much in the same way as Jason may have
seen the golden sands worked in Asia Minor. The sands
accumulating on the blankets were washed off at intervals

492 SCIENCE PROGRESS.

and ground in mills with mercury. In addition the ore was
frequently passed over or through baths of mercury (as is
still done in many Australian mills) and concentrated
in various ways. Amalgamated copper plates over which
the pulp flowed were tried, but in Western America were
at first almost everywhere rejected,1 probably owing to the
great depth of the stream of ore and water made to flow
over them. When this mistake began to be rectified some
twenty-five years ago the value of the plates was soon
recognised in California.

In the extraction of gold from crushed ore by means of
amalgamated copper plates, the pulp- is led over their
surface in a very thin stream, not more than a quarter of
an inch deep. The plates are slightly inclined, wider than
the screens from which the pulp issues, and from six to
twelve feet long. The pulp does not run down in a regular
stream, but in a series of little wavelets which tumble over
and over and are supposed to bring every part of the pulp
in succession in contact with the amalgamated surface. The
catching powers of the plates are thus supposed to be prac-
tically independent of the tendency of the particles of gold
or amalgam to sink to the bottom of the stream. This
theory is not accepted by the Austrian school, and it is
certain that native gold is caught more easily in proportion
as it contains less silver, so that when the particles of metal
consist of an alloy largely consisting of silver, and are
therefore of comparatively low density, the yield on the
plates is generally poor. In any case, however, the
amalgamated plate should theoretically be better adapted
for its work than the Tyrolean mill and other machines
using mercury baths, owing to the slight depth of the
pulp on the plates and the short distance through which
the gold particles are compelled to settle before reaching
a catching surface. The plates are wiped down with
rubber or brushes about once a day and the gold sepa-
rated in the usual way from the excess amalgam thus
collected.

1 See Nevada and California Processes of Silver and Gold Extraction,
p. 6 1, by G. Kiistel, San Francisco, 1863.

GOLD EXTRACTION PROCESSES. 493

Admirable as is the amalgamation process in many
respects, it has always been recognised that the extraction
of gold by its use is generally far from complete. Besides
the comparatively large particles of free gold which are
readily saved by amalgamation, all ores contain more or
less gold in an excessively fine state of division (the aurum
larvatum or "disguised" gold of the last century) as well
as gold contained in sulphides {aurum miner alisatum),
and these particles cannot be extracted by the copper
plates.

In an investigation on the dimensions of gold particles in
ores J. A. Edman 1 observed a single chip of quartz tV inch
in diameter which, when magnified 50 diameters, showed
over 300 particles of gold, varying in size from ToVo to
titoo inch not only on the surface of the stone but scattered
through the transparent mass. Higher powers showed still
greater numbers of smaller particles. The gold contained
in pyrites, if, as seems likely, it is generally free, must be
often still finer. It has been likened to the mortar in a
brick wall, and is almost as difficult to catch as the motes in
a sunbeam. Prolonged grinding with mercury no doubt
increases the chances of such gold being amalgamated,
and hence the success which has frequently attended the
use of the Mexican arrastra, where the grinding surfaces
are of stone, and of its successor the iron amalgamating
pan.

Nevertheless, the yield of gold, mainly owing to the
"flouring" and "sickening" of the mercury, is not always
good even in these slow-working and therefore costly ma-
chines. Mercury, when triturated with ore for a long time,
tends to break up into very fine particles which, although
apparently clean and bright under the microscope, refuse to
run together, and are carried away by the stream of water and
lost, together with the gold already taken up by them. Such
mercury appears greyish-white, and is said to be " floured".
Moreover, when base metals are present in the ore they
become amalgamated, and then, oxidising, coat the surfaces

1 Mining and Scientific Press. San Francisco, 12th August, 1892.

494 SCIENCE PROGRESS.

of the globules of mercury with black scum, which effectually
prevents the amalgam from adhering either to gold or to
amalgamated plates. This "sickening" is doubtless also
caused by the formation of compounds of the mercury
itself. Ores containing sulphides of arsenic or antimony
(which are reduced by mercury) are particularly apt to
cause " sickening," but manganese dioxide, partly decom-
posed copper pyrites, zinc blende, and galena are also
harmful.

It has been well known ever since the time of Agricola
that the gold contained in these minerals, although not easy
to extract by mercury, may be readily obtained by concen-
trating the ore (all finely divided free gold being, of course,
lost in the process) ; the concentrates are then smelted, the
gold accumulated in a reduced metal, such as lead or
copper, and subsequently separated by cupellation or
other means. The impossibility of applying this method
of procedure to individual mines far distant from coal beds,
and in places where a mixture of different kinds of ore
cannot be obtained, prevents the universal application of
the method, although in the neighbourhood of such smelt-
ing centres as Freiberg and Denver nothing better is
required.

The chlorination process, now nearly fifty years old, is of
more general value for treating concentrates. Chlorine is a
somewhat slow solvent for gold, any particle occurring
native which is visible to the unassisted vision requiring
many hours for its complete dissolution ; but it is well
adapted to dissolve the fine flakes existing in pyrites.
Unfortunately chlorine has a strongly preferential action
on sulphides, and to avoid the enormous waste of gas
which a small percentage of these substances cause it is
necessary to precede chlorination by careful and complete
roasting. After this there is little difficulty in the process.
Oxides of the metals, except the alkaline earths, are very
slowly attacked by chlorine ; and when the alkaline earths
are present salt is added in the roasting furnace. Chlorine
is applied to the slightly clamped ore in the form of gas,
or, in more modern practice, as a strong aqueous solution.

GOLD EXTRACTION PROCESSES. 495

After a day or two the liquid is filtered off, and the
gold precipitated by ferrous sulphate or sulphuretted
hydrogen.

The problem of the extraction of gold contained in
pyrites and complex minerals was partially solved by the
chlorination process, but the cost of roasting is a stumbling-
block in many cases, and it was the desirability of avoiding
this which led to the introduction of the use of cyanide
solutions for leaching, probably the most important event in
the history of the metallurgy of gold since the first applica-
tion of mercury to gold extraction. The extraordinary
properties of very dilute solutions of cyanide of potassium
were unmarked and in great part unknown until quite
recently. That metallic gold is soluble in alkaline cyanides
unaided by an electric current remained an interesting but
useless fact until it was found that a solution containing
only one per cent, of potassium cyanide dissolves gold at
least as rapidly as much stronger solutions, although it
has a very slow and partial action on most sulphides and
other minerals occurring in gold ores. The presence of
free oxygen is necessary for the dissolution of the gold,
which takes place according to the equation —

4A11 + SKCy + Oo + 2 H20 = 4KAuCy2 + 4KHO.

The oxygen is supplied from the air entangled in the porous
ore, or dissolved in the solutions, in which MacLaurin * has
shown that it can be retained in the presence of alkaline
cyanides in spite of its rapid absorption by the latter with
the formation of cyanates. The gold can be recovered by
precipitation on zinc and subsequent melting, or by electro-
deposition on suitable cathodes, of which lead only has been
largely used.

The development of the cyanide process proceeded
apace as soon as it had been introduced. The mechanical
improvements devised were numerous, the most important
being the enlargement of the size of the leaching vats, until
the largest now hold 600 tons of ore. The chief chemical
improvements have been the introduction of the use of

xJvur. Chem. Soc, vol. lxiii., p. 724 (1893).

496 SCIENCE PROGRESS.

caustic soda or lime to neutralise the acids and acid salts
in " weathered ': pyritic ores, and the reduction in the
strength of solutions, the favourite "strong" solution now
containing from 0*25 to 0*30 per cent, of available KCy,
while solutions as weak as o"Oi per cent, are found in many
cases to be equally efficacious if a somewhat longer time is
allowed. In accordance with the experience in the extrac-
tion mills MacLaurin 1 has found that gold and silver in the
form of plates are most rapidly dissolved by solutions con-
taining from ci to 0*4 per cent, of cyanide, the maximum
rate being observed with solutions containing about 0*25
per cent, of cyanide of potassium. A fairly rapid rate of
dissolution however is still observable when only 0*005 Per
cent, of KCy is present.

Cyanide of potassium acts rapidly when free oxygen is
present in large quantities, as for example when gold floats
on the solution, with its upper side dry. Under such con-
ditions, cyanide is at least as rapid in action as chlorine, but
in proportion as the supply of free oxygen falls off, the rate
of dissolution of gold in cyanide becomes slower, and when
air is excluded as rigidly as possible, hardly any action can
be observed. In practice these facts are of importance.
Finely divided gold in ordinary ores is dissolved in two or
three days. When concentrates containing a large propor-
tion of sulphides are being treated, however, free oxygen is
absorbed by the pyrites as well as by the solution, and the
treatment lasts as much as two or three weeks with a
corresponding increase in the destruction of the cyanide by
the minerals in the ore. An artificial supply of oxygen
or of oxidising agents shortens the time required, but in-
creases the waste of cyanide. Moreover, when pyritic ores
or concentrates contain much marcasite and, in many cases,
when copper sulphides or some other minerals are present,
the process is useless, enormous quantities of cyanide being
converted into other compounds before any gold is dissolved.

The process is therefore of limited application to com-
plex ores and concentrates generally, although of wide
applicability to ores comparatively free from sulphides,

1 Jour. Chem. Soc, loc. cit. and vol. Ixvii., p. 199, 1895.

GOLD EXTRACTION PROCESSES. 497

especially after the coarser particles of gold have been
removed by amalgamation. Certain deposits of complex
ores, above the average in richness, are at present left
untouched for want of a process by which they can be
treated.

The cost of treatment of gold ores by the processes de-
scribed above of course varies enormously with the locality
and the special conditions of the case. Under favourable
conditions the following may indicate approximately the
minimum amount of gold which must be present in an ore,
in order that it may be treated at a profit by the most
suitable process. Auriferous sand, washed in the miner's
pan, must contain about one part of gold in 100,000 or say
six pennyweights per ton of ore. When the sluice is used,
the sand being excavated and carried to the sluice by hand
labour, as in Siberia, there must be at least one part of
gold in 2,500,000 parts of sand or six grains to the ton.
When the hydraulic method is possible, only one part in
18,000,000 may be enough, or three-fourths of a grain of gold
per ton, a proportion about equal to that which Liversedge1
found to exist in the sea water off the east coast of
Australia. If the gold is contained in quartz, the cost of
mining and of crushing the stuff makes the whole process
of treatment far more expensive. Excluding the cost of
mining, however, the cost of crushing and amalgamation
requires the presence of at least one part of gold in
400,000, or say one and a half dwts. per ton. The cost of
chlorination is equal to not less than one part of gold in
200,000 of ore or three dwts. per ton, although if only
applied to concentrates, the cost per ton of the original ore
may be trifling. Lastly, the cyanide process might be
applied to the crushed tailings from the amalgamation
process if they contain more than one part of gold in
600,000 or one dwt. per ton. If the ore has to be crushed,
it must of course be richer. As stated above, these
estimates apply only when the conditions are the most
favourable. In general, such poor ores could not be worked
at a profit.

1 Proc. Roy. Soc. of MS. W., 1895.
35

498 SCIENCE PROGRESS.

At the present time the annual production of gold from
all these sources is about ^42,000,000 per annum, or double
the output of seven years ago. It is greater than at any
previous period in history, the nearest approach to it having
been made in 1853, when the river gravels of California
and Australia were at their best. The output was then
estimated at ^"38,000,000.

Of the present output, washing processes, formerly in-
strumental in producing by far the larger proportion of
the gold won, are now probably answerable for no more
than 30 per cent. The amalgamation of crushed vein
stuff, now the most important process, produces about 55
per cent, of the whole gold production. The two wet
processes, chlorination and cyanide, account for some 1 1
per cent, of the output, of which about two-thirds are
contributed by the cyanide process, and, lastly, smelting
perhaps produces 3 or 4 per cent, of the total. In the
future, as placer gravels become exhausted more and more,
the proportion of the output derived from them will
continue to fall off, and the greatest increases will certainly
take place in the produce from stamp battery amalgamation
and the cyanide process. The output from chlorination
and from smelting has been for some years stationary or
declining, and their proportion of the world's production
will doubtless suffer a continued though gradual reduction.
It is obvious that by new discoveries the whole direction
and progress of the art might be modified. As the old
deposits become exhausted the miner is compelled to go
deeper into the earth and the metallurgist to treat poorer
and more refractory ores. " Such is the vast labour ex-
pended on the extraction of gold. And from this descrip-
tion I think it is clear that gold is hard to get as it is
difficult to keep ; and though all men long to get it, yet
when they have it they find as much pain as pleasure in
the use of it." l

T. K. Rose.

1 Diodorus Siculus, book iii., chap. 12. Quoted by B. H. Brough,
ioc. cit. an tea.

THE MOST RECENT VALUES OF THE MAG-
NETIC ELEMENTS AT THE PRINCIPAL
MAGNETIC OBSERVATORIES OF THE
WORLD.

-From Data kindly supplied by Kew Observatory

Committee.

THE data in the table are deduced from hourly readings
of the magnetic curves in the case of Pawlowsk,
Katharinenburg, Copenhagen (Declination and Horizontal
Force), Hamburg (Declination), Wilhelmshaven (Declina-
tion), Potsdam, Irkutsk, Utrecht (Declination), Kew, Green-
wich, Uccle (Declination), Falmouth (Declination and
Horizontal Force), Pare Saint Maur, Vienna, Pola, Nice
(Declination), Perpignan, Tiflis, Washington, Zi-ka-wei,
Manila, Batavia, and Mauritius.

In the case of Kasan (Declination and Horizontal Force),
Prague (Declination and Horizontal Force), O'Gyalla (De-
clination and Horizontal Force), Madrid (Declination),
Coimbra (Declination), and Lisbon (Declination), the diur-
nal inequality has been at least partly allowed for by the
employment of readings at two or more hours of the day.

The first results of Inclination and Vertical Force at
Greenwich are deduced from readings with 3-inch dip
needles only, the second from readings with 3, 6, and
9 inch needles. Allowance has been made for a slight
disturbance through recent building, in accordance with
data kindly supplied by the Astronomer Royal.

The Declination at Kasan in last year's table was
erroneously given as West.

500

SCIENCE PROGRESS.

Place.

Latitude.

Longitude.

Year.

Declination.

Pawlowsk

59°4i'N.

3°° 29'

E.

1894

o° 10' -5 E.

Katharinenburg

56° 49' N.

60° 38'

E.

1894

9° 39-4 E.

Kasan

55°47'N.

49° 8'

E.

1892

70 3o'-8 E.

Copenhagen

55°4i'N.

120 34

E.

1893

io° 47'7 W.

Stonyhurst

53°5i'N.

2° 28'

W.

1895

1 8° 37'-8 W.

Hamburg

53° 34' N.

IO° 3'

E.

i895

ii° 42'7 W.

Wilhelmshaven

53° 32' N.

8° 9'

E.

1895

I2°52'-5 W.

Potsdam -

520 23' N.

i3° 4

E.

1891

IO° 42'-2 W.

Irkutsk -

520 16' N.

1040 16'

E.

1894

2° 8'-o E.

Utrecht -

52° 5'N.

50 11'

E.

1893

140 28'-5 W.

Kew

51° 28' N.

o° 19'

W.

1895

1 70 i6'-8 W.

Greenwich

510 28' N.

0° 0'

1895

i6°57'-4W.

Uccle (Brussels)

500 48' N.

40 20'

E.

1893

140 48^7 W.

Falmouth

5°° 9'N.

5° 5'

W.

1895

1 3° 54-5 W.

Prague

5o° 5'N.

14° 25'

E.

1895

9° 3i'*5 w-

Pare St. Maur (Paris)

480 49' N.

2° 29'

E.

1893

15° 2l'-I W.

Vienna -

48° 15' N.

1 6° 21'

E.

1894

8° 43'-6 W.

O'Gyalla (near Buda

Pesth) -

—

—

1894

70 5S'-2 W.

Pola (on Adriatic) -

44°52'N.

13° 5°'

E.

1895

90 47'-o \V.

Nice

43° 43' N.

70 16'

E.

1893

120 32^7 W.

Toronto -

43° 4o' N.

79° 3°'

W.

1894

4° 43'*9 w-

Perpignan

420 42' N.

20 53'

E.

1893

140 10' -5 W.

Rome

4i°54'N.

12° 27'

E.

1891

io°45'-i W.

Tiflis

410 43' N.

44° 48'

E.

1893

i° 38'-o E.

Madrid -

400 25' N.

3° 4o'

W.

1893

1 6° i4'-2 W.

Coimbra -

400 12' N.

8° 25'

W.

1893

i7"5i'7 W.

Washington

38° 53' N.

77° 0'

w.

1892

40 1 4'' 2 W.

Lisbon

38° 43' N.

9° 9'

w.

1893

i7°49'-4 W.

Zi-ka-wei -

310 12' N.

121° 26'

E.

1894

20 i6'"5 W.

Hong-Kong

22° 18' N.

II40 io'

E.

1894

o° 29'-2 E.

Colaba -

1 8° 54' N.

72° 49'

E.

1894

o° 38' -6 E.

Manila -

14° 35' N.

1270 II'

E.

1894

o° So'-4 E.

Batavia -

6° 11' S.

1060 49'

E.

1894

i° 27'-6 E.

Mauritius

200 6' S.

57° 33

E.

1893

IO° 2- 1 W.

Melbourne

37° 5°' S.

144° 58'

E.

1894

8° i3'-6 E.

RECENT VALUES OF MAGNETIC ELEMENTS. 501

Horizontal

Vertical

Place.

Year.

Inclination.

Force,
C.G.S. Units.

Force,
C.G.S. Units.

Pawlowsk

1894

70° 43'-6 N.

•16456

•47061

Katharinenburg

1894

70° 40' -o N.

•17799

•50729

Kasan -

1892

68° 36'-2 N.

■18SSI

•47345

Copenhagen -

1893

68"5i'-o N.

•17358

•44868

Stonyhurst

1895

68°59'-2 N.

•17148

•44637

Hamburg

1895

67° 44'"3 N-

•18009

"43994

Wilhelmshaven

1895

67° 54'"5 N.

•17983

•443°5

Potsdam

1891

66° 44'-i N.

•18635

•43342

Irkutsk -

1894

70° io'-5 N.

•20116

•55796

Utrecht

1893

67° I2''2 N.

•18397

•43772

Kew

1895

67° 23'-8 N.

•18278

•43901

Greenwich

1895

( 67° i5'-9 N. 1
1 67"i4'-9N. /

•18323

< "43727 I
( '43692 J

Uccle -

1893

66° 28'-4 N.

•1877

"4311

Falmouth

1895

67° o'"4 N.

•18547

•437o8

Prague -

1895

—

•19834

—

Pare St. Maur

1893

650 7'-i N.

•19621

•42304

Vienna -

1894

63° I2'-I N.

•20740

•41061

O'Gyalla

1894

—

•21054

—

Pola -

1895

6o° 34' -o N.

•22026

•39038

Nice

1893

6o° 26' -4 N.

•22198

•39!39

Toronto

1894

74° 35''o N-

•16624

•60286

Perpignan

1893

6o° n'-g N.

•22304

•38944

Rome -

1891

58° 4' -6 N.

•2324

•373o

Tiflis -

1893

55°45'7N.

•25692

•37751

Madrid -

1893

—

—

—

Coimbra

1893

59° 50' -5 N.

•22518

•38752

Washington -

1892

71" 3'-9N.

•19848

•57858

Lisbon -

1893

580 24-6 N.

•23270

•37840

Zi-ka-wei

1894

46° o'7 N.

•32613

•33785

Hong-Kong -

1894

3i°53'^ N.

•36450

•22675

Colaba -

1894

200 4o'7 N.

■37426

•14126

Manila -

1894

1 6° 54-3 N.

•37740

•11470

Batavia -

1894

29° i3'7 s-

•36749

•20563

Mauritius

1893

54° 44-3 S.

•239S9

•33929

Melbourne

1894

67° i6'«9 S.

•23426

•55956

APPENDIX I.

NOTICES OF BOOKS.

Studies in the Evolutionary Psychology of Feeling. By Hiram M. Stanley. London : Swan
Sonnenschein & Co. New York : Macmillan & Co., 1895. Pp. viii., 392.

The chief idea pervading the book is the importance of mind in evolution. The
reasoning starts from the assumption that the primitive form of consciousness was pain, and
pain is held to have been the essential factor in the evolution of mind by means of its stimu-
lating action on volition. Not only the higher mental developments, but even the senses are
supposed to owe their existence to conscious struggle in the effort to avoid pain. The course
of evolution is supposed to have been pain — pleasure — vague cognition of object — sensation.
In considering the emotions, of which fear is held to be the most primitive, the author does
not believe in their gradual evolution, but supposes that such an emotion as anger appeared
discontinuously in some favoured individual that derived advantage from the power of " getting
mad " and violently attacking its fellows. The book is not scientific in method, but contains
some useful discussions of psychological questions.

Milk ; Its Nature and Composition. A Handbook on the Chemistry and Bacteriology of Milk,
Butter and Cheese. By C. M. Aikman, M.A., D.Sc. London: Adam & Charles
Black, 1895. Pp. xiv., 173. Price 3s. 6d.

In the space of less than 200 pages Dr. Aikman has contrived to give a good general
account of the more important facts concerning milk — a valuable food which it behoves the
general public no less than the milk purveyor and the dairy farmer to thoroughly under-
stand.

Many persons having charge of children and invalids who subsist largely on milk have
but a scanty knowledge of its composition and peculiarities : to these as well as to those in
charge of dairy farms Dr. Aikman's book will prove of value, as in addition to a good description
of the perfect article, the "faults" of milk, the bacteria found in it, and the food stuffs
prepared from it are fully treated.

The value of the work is increased by the presence of well-selected figures in the text, and
a short list of works on dairying in an appendix.

Handbuch der palaarktischen Gross-Schmetterlinge fiir Forscher und Sammler. Zweite
gdnzlich umgearbeitete und durch Studien zur Descendenztheorie erweiterte Auflage des
Handbuches fur Sammler der europdischen Gross-Schmetterlinge. Von Dr. M.
Standfuess, Dozent beider Hochschulen und Kustos des Entomologischen Museums am
eidgen. Polytechnikum zu Zurich, mit 8 lithographischen Tafeln und 8 Textfiguren.
Jena : Gustav Fischer, 1896, 8vo, pp. xii., 392.

This book is a curious medley, combining several branches of entomology which we are
seldom accustomed to see discussed in the same work, at least in England. The author
complains in his preface that too many entomologists are mere collectors, or at least concern
themselves only with questions of species ; and therefore he has made his work not only a
comprehensive handbook of the formation and management of a collection, but has added
large sections relating to variation, dimorphism, hybridism, and other subjects connected with
the origin of species, illustrated with eight coloured plates. Most of the varieties, hybrids, etc.,
represented belong to well-known British species. The more scientific portion of the book
is in large measure an addition to the contents of the earlier and smaller edition.

The author is by no means satisfied with the present position of entomology among the
sciences, which he attributes to the already mentioned neglect of scientific entomology among
collectors. Apparently he hopes to contribute to an improvement in this direction, and he
thus expresses his views in the preface : —

' ' This is the principal reason why the technical entomological literature of the time is
almost totally neglected by scientific zoology, and ignored. In future it must not be thus.

A

ii SCIENCE PROGRESS.

Entomology must not be treated as a stepchild and Cinderella, to be neglected by her proud
sister, but must work shoulder to shoulder with her as a faithful and equal comrade, carrying
stones for the building which inquirers are endeavouring by honest work, upon a true knowledge
of nature, to raise up as a harmonious whole."

A Handbook of British Lepidoptera. By Edward Meyrick, B.A., F.Z.S., F.E.S., Assistant
Master at Marlborough College. London and New York : Macmillan & Co. , 1895.
8vo, pp. vi., 843.

In this compact and closely-printed volume Mr. Meyrick has given us a convenient
Students' Manual of British Butterflies and Moths, which was greatly wanted by all collectors
who had outgrown the numerous popular books, which, as a rule, include only the butterflies
and larger moths, the far more numerous " Micro-Lepidoptera " being omitted. Mr.
Meyrick's work, however, includes all these in a single volume, not, of course, giving com-
plete information on every point, but short descriptions and tables of genera and species, and
notices of larvae, times of appearance, and localities. We have many similar handbooks of
botany and ornithology, and it is rather surprising that this is almost the first of its kind as
regards Lepidoptera. There are no illustrations except woodcuts of neuration, a character to
which Mr, Meyrick attaches a perhaps somewhat exaggerated importance. Enough has been
and will be written elsewhere on the new classification of the Lepidoptera proposed by Mr.
Meyrick, and we need only here allude to the fact of its being totally dissimilar to that adopted
by any other entomologist.

Catalogue of the Mesozoic Plants in the Department of Geology, British Museum (Natural
History). The Wealden Flora. Part II., " Gymnospermas ". With twenty Plates
and nine Figures in the Text. By A. C. Seward, M.A. , F.G.S. London : 1895.

Mr. Seward, of Cambridge, has for some time past been engaged on an examination of
the fossil plants from the Wealden beds, contained in the collections of the British Museum.
The material on which the investigation is based was for the most part collected by Mr.
Rufford, whose valuable specimens have been acquired by the Museum. Mr. Seward's first
volume, containing the "Cryptogams," appeared in 1894; the part now published completes
the work, for, unfortunately, the English Wealden has not yet yielded any Angiospermous
remains, although both Monocotyledons and Dicotyledons have been found in beds of similar
horizon abroad.

The present volume is concerned with the two orders Cycadacese and Coniferae. The
author, however, points out that we are still to a large extent in the dark as to the exact nature
and structure of extinct Cycadean plants. Beautiful as many of the specimens are, and
striking as is the similarity of their organs to those of existing Cycads, we can seldom be
certain that we have to do with Cycadaceas, in the sense of recent Botany. There is nearly
always the possibility that the remains may rather belong to the extinct family Bennettiteae,
allied to the Cycads, but deviating widely from them in the structure of the reproductive
organs. Mr. Seward appears to recognise one species only (among those recorded in this
book) as representing a truly Cycadean flower. This is his Androstrobus Nathorstii, which
seems to be beyond doubt a male cone of the true Cycadean type. The other fructifications
described are regarded as " incertce sedis," or transferred to the Coniferae, or else they belong
unmistakably to the Bennettites type. This latter fructification, so thoroughly known from the
researches of Carruthers, Solms-Laubach, and Lignier, is proved by the author to be well re-
presented in the Wealden strata. He founds a new species — Bennettites Carruthersi — for some
very fine specimens, which exhibit in great perfection all the more external characters of this
extraordinary fructification. Mr. Seward identifies Bennettites with the famous Williamsonia,
and inclines to the view that all the specimens which have been satisfactorily determined repre-
sent female inflorescences. Another species of Bennettites illustrates very finely the way in
which the inflorescences were borne on the stem.

Certain Wealden stems had been referred by previous writers to Draccena. The author
rejects this determination, and shows that they bear a much greater likeness to certain
Cycadean stems, especially those of some species of Zamia.

A most anomalous fossil, of uncertain affinities, is placed by Mr. Seward in a new genus —
Withamia. It consists of a woody axis, bearing very large recurved spines, in the axils of
which leaf-like organs, somewhat suggestive of a GiwfAo, are seated. Nothing like this is
known among living plants, though Phyllocladus presents certain analogies.

NOTICES OF BOOKS. in

Many beautiful coniferous specimens are recorded, from which it would appear (though
the author here, as indeed everywhere, expresses himself with the most admirable caution)
that rnost tribes of Coniferae were already represented in the Wealden epoch. A new species
of Pinites (P. Sol??isi) shows both foliage and female cones very clearly, and decidedly
suggests the recent genus, while in Sphenolepidium Kurrianum we have equally perfect
specimens of another type, indicating an affinity to Athrotaxis.

The author considers that the evidence of Palasobotany certainly favours the inclusion of
the Wealden rocks in the Jurassic series.

Such work as Mr. Seward's is of the greatest possible value. His book, with the help of
the abundant and excellent illustrations (chiefly the work of Miss Woodward), gives us a vivid
idea of the flora of a most interesting epoch. The author's remarkably sound judgment, and
caution in estimating affinities, inspire great confidence in his results. It is only by such
sober-minded work as this that real and permanent advance in fossil Botany can be assured.

Die Artbildung und Verwandschaft bei den Schmetterlingen. II. Theil. Eine systematische
Darstellung der Abanderungen, Abarten und Arten der Schwalbenschwanz-ahnlichen
Formen der Gattung Papilio. Von Dr. G. H. Theodor Eimer, Professor der Zoologie
und vergleichenden Anatomie zu Tubingen. Unter Mitwirkung von Dr. K. Fichert, I.
Assistent an der Zoologischen Anstalt daselbst. Mit 4 Tafeln in Farbendruck und 7
Abbildungen im Texte. Jena, 1895.

Times have changed since it was possible to regard a fondness for butterfly collecting as
evidence which could be seriously brought forward in a court of justice in an attempt to set
aside the will of a deceased lady on the ground of insanity. Gone, too, are the days when it
was necessary for pious and learned gentlemen to explain to our fathers in long and elaborate
essays that Entomology was not in itself either a frivolous or a cruel amusement. Yet the
really cruel amusements of the beginning of the century have disappeared and are forgotten,
while Entomology still holds its own, and to judge from the large number of books addressed
chiefly to amateurs, is an increasingly popular amusement, while wise men are turning their
attention to the despised butterflies in quest of information respecting some of the profoundest
problems which are open to our scientific men along the present tracks of ordinary research.

It was Bates' famous paper on Mimicry which first began to raise the philosophical study of
butterflies to the importance which it has now attained, and questions of mimicry, variation,
adaptation, climate, and even of the past history of the world, and of the formation of species
are eagerly discussed in the new light which the study of butterflies has thrown upon them.

Not only long and extended but much detailed examination is necessary before satis-
factory results can be attained ; and therefore works of a limited character like Dr. Eimer's1 will
always be important, quite apart from any theories which may be based upon them. Dr.
Eimer contends that Natural Selection will not account for the origin of species, though it
doubtless contributes largely to the preservation of species that are already formed. He also
adduces instances in which the representative forms of a species or group of species appear to
vary in a similar direction at the opposite extremities of its range ; but perhaps his most
important point is that variation always appears to occur along definite lines. We are glad to
notice this, because, although it has frequently been noticed, it has generally been passed by
without special comment. It would be impossible to discuss Dr. Eimer's theories at length ;
but we are sure that all who are interested in the philosophical study of butterflies will read his
book with much interest.

1 The present volume of his work is restricted to Papilio Turnus, Machaon, and Asterias, and their
allies.

APPENDIX II.

CHEMICAL LITERATURE FOR JANUARY, 1896.

Vol. i. No. 2. American Journal 0/ Science. (February, 1896.)

Walker, T. L., Notes on Sperrylite (pp. 110-113). Penfield, S. L., and Forbes, E. H.,
Fayalite from Rockport, Mass., and on the Optical Properties of the Chrysolite-Fayalite
Group, and of Monticellite (pp. 129-136).

Vol. xviii. No. 1. Journal of the American Chemical Society. (January, 1896.)

Heidenhain, H., On the Determination of Carbon Dioxide by Absorption (pp. 1-8). Cross, C.
F., Sevan, E. J., and Beadle, C, The Natural Oxycelluloses (pp. 8-21). Gill, A. H.,
and Richardson, H. A., Notes on the Determination of Nitrites in Potable Water (pp.
21-23). Gladding, T. S. , A Gravimetric Method of Estimating Phosphoric Acid as Am-
monium Phosphomolybdate (pp. 23-28). Flintermann, R. F., and Prescott, A. B.,
Dipyridine Trimethylene Dibromide and a Study of Certain Additive Reactions of Organic
Bases (pp. 28-35). Campbell, E. D., A Proposed Schedule of Allowable Difference and
of Probable Limits of Accuracy in Quantitative Analyses of Metallurgical Materials (pp.
35-38). Pennington, M. E., Derivatives of Columbium and Tantalum (pp. 38-67). Gill,
A. H., An Improved Gas Pipette for the Absorption of Illuminants (pp. 67-68). Richards,
E. H, , and Films, J. W. , The Colouring Matter of Natural Waters ; its Source, Composi-
tion and Quantitative Measurement (pp. 68-81). Wiley, H. W., On the Estimation of
Levulose in Honeys and other Substances (pp. 81-91). Prescott, A. B., Notes on a few
Pyridine Alkyl Iodides (pp. 91-96). Rising, W. B., and Lenher, V., An Electrolytic
Method for the Determination of Mercury in Cinnabar (pp. 96-98).

Vol. xviii. No. 1. American Chemical Journal. (January, 1896.)

Jackson, J. C. L., and Oenslager, G., On the Constitution of Phenoquinone (pp. 1-23). Warder,
R. B., The Mathematical Theory of Oxidation Processes (pp. 23-43). Mabery, C. F., On
the Composition of the Ohio and Canadian Sulphur Petroleums (pp. 43-80).

Vol. xxi. No. 239. The Analyst. (February, 1896.)
President's Annual Address (pp. 29-36).

Vol. lxix. No. 399. Journal of the Chemical Society. (February, 1896.)

Marsh, J. E., and Gardner, J. A., Researches on the Terpenes. VI. Products of the Oxida-
tion of Camphene, Camphoic Acid and its Derivatives (pp. 74-91). Cohen, J. B., and
Archdeacon, W. H., The Action of Sodium Alcoholate on the Acid Amides (pp. 91-96).
Ewan, T., Note on the Electrolytic Conductivity of Formanilide and Thioformanilide
(pp. 96-98). Snape, H. L., On Certain Phenylthiocarbamates (pp. 98-102). Shaw, G. E.,
Periodides of Theobromine (pp. 102-104). Frankland, P. F, and MacGregor, J., Ethe-
real Salts of Active and Inactive Monobenzoyl-, Dibenzoyl-, Diphenacetyl- and Dipropionyl-
Glyceric Acids (pp. 104-123). Frankland, P. F., and Pickard, R. H., Rotation of
Optically Active Compounds in Organic Solvents (pp. 123-142). Nicol, W. W. /., The
Molecular Volumes of Organic Substances in Solution (pp. 142-145).

Vol. xli. No. 249. Philosophical Magazine and Journal of Science. (Feb., 1896.)

Wood, R. W., On the Dissociation Degree of some Electrolytes at 0° (pp. 117-120). Wood,
R. W., The Duration of the Flash of Exploding Oxyhydrogen (pp. 120-123).

Vol. lix. No. 353. Proceedings of the Royal Society. (15th January, 1896.)

Lockyer, J. N., On the Gases obtained from the Mineral Eliasite (pp. 1-4). Lockyer, J. N., On
the New Gases obtained from Uraninite. VI. (pp. 4-9). Kuerten, J. P., and Randall,

ENUMERATION OF TITLES. v

W. W., The Expansion of Argon and of Helium as compared with that of Air and
Hydrogen (pp. 60-66). Kellas, A., On the Percentage of Argon in Atmospheric and in
Respired Air (pp. 66-68). Kellas, A., and Ramsay, W., Examination of Gases from
certain Mineral Waters (pp. 68-69). Lundstrom, C. /., Flame Spectra observed at
Swedish Bessemer Works (76-98). Hartley, W. N. , Remarks on the Origin of some of
the Lines and Bands observed in the Spectra from Swedish Bessemer Works (pp. 98-101).

Series vii. Tome vii. Annates de Chimie et de Physique. (February, 1896.)

Marie, T., Recherches sur les acides ceYotique et melissique (pp. 145-251). Louguinine, W.,
E*tude sur les chaleurs latentes de vaporisation des liquides (pp. 251-283). Berthelot, Sur
la determination thermochimique de l'equivalent des acides et des bases (pp. 283-288).

Tomes xv.-xvi. No. 2. Bulletin de la Societe Chimique de Paris.
(20th January, 1896.)
Lenoble, E., Sur le nouveau mode de representation des courbes de solubility des sels,
propose" par M. Etard (pp. 54-58). Rousset, L., Sur quelques acetones derivees du
naphtalene (pp. 58-72). Cazeneuve, P., Recherches sur la decomposition des acides-
phenols derives du benzene et du naphtalene (pp. 72-82). Lauth, C, Sur quelques
derives dithiazoliques (pp. 82-87). Grimbert, L., Fermentations provoquees par le
pneumobacille de Friedlander (pp. 87-96). Bechamp. A., Sur les alterations spontanees du
lait et sur celles que la cuisson lui fait subir (pp. 96-118). Lasne, H., Sur le dosage de
l'alumine dans les phosphates (pp. 1 18-128).

Tomes xv.-xvi. No. 3. (5th February, 1896.)

Brunei, H., Sur l'acide thioglyoxylique (ethanethioloi'que) (pp. 134-135). Bredt, J., et de
Rosenberg, Synthese partielle du camphre (pp. 135-142). Prud'homme, M„ Nouvelle
synthase de la parafuchsine et de ses derives mono-, di-, tri- et tetraalcoyk4s (pp. 142-146).
Lasne, H., Sur le dosage de l'alumine dans les phosphates. II. (pp. 146-158). Colson,
A., Essai sur le dosage polarimetrique de l'acide tartrique (pp. 158-162). Winter, /.,
Note additionelle a un memoire paru dans le Bulletin de la Societe Chemique [y. serie,
t. xiii., pp. 1101-1895), sur la temperature de congelation des liquides de l'organisme
(pp. 162-163).

Tome cxxii. No. 1. Comptes Rendus hebdomadaires de V Academie des Sciences.

(6th January, 1896.)
Thomas, V., Action du peroxyde d'azote sur les sels halog^nes d'etain (pp. 32-34). Oechsner
de Coninck, Sur un mode de decomposition de quelques composes a fonction amide ou
basique (pp. 34-35).

Tome cxxii. No. 2. (13th January, 1896.)

Amagat, E. H., Sur les variations du rapport des deux chaleurs specifiques des gaz (pp. 66-70).
Violle, J., Un etalon photomemque a l'acetylene (pp. 79-80). Le Chatelier, H., Sur la
chaleur de formation de quelques composes du manganese (pp. 80-82). Tassilly, Sur les
iodures cristallises de strontium et de calcium (pp. 82-84). Barbier, P., et Bouveault, L.,
Sur les aldehydes derivees des alcools Cio H18O isomeriques (pp. 84-86). Tan ret, Sur la
multirotation des sucres redacteurs et l'isodulcite (pp. 86-87).

Tome cxxii. No. 3. (20th January, 1896.)

Amagat, E. H., Sur les chaleurs specifiques des gaz et les propri6t£s des isothermes (pp.
120-121). Parmentier, P., Sur la solubility de l'hyposulfite de soude dans l'alcool
(PP- I35"I37)- Marie, C, et Marquis, A., Sur le nitrosulfures de fer (pp. 137-140).
Besson, A., Action du chlorure de carbonyle sur quelques composes hydrogens (pp. 140-
142). Meunier, J., Sur le dichloral glucose et sur le monochoral glucosane (pp. 142-144).

Tome cxxii. No. 4. (27th January, 1896.)

Francois, M., Action de la chaleur sur l'iodure mercureux (pp. 190-193). Bayrac et Camichel,
C, Sur l'absorption de la lumiere par les dissolution d' indoph^nols (pp. 193-195).
Perrier, G. , Combinaisons du chlorure d'aluminium anhydre avec les phenols et leurs
derives (pp. 195-198). Bouckardat, G., et Tardy, Sur l'essence d'anis de Russie (pp.
198-201). Brocket, A., Sur la production de l'aldehyde formique gazeuse pure (pp.
201-203).

vi SCIENCE PROGRESS.

Tome cxxii. No. 5. (3rd February, 1896.)
Meslans et Girardet, F., Sur les fluorures d'acides (pp. 239-243). Co/son, A., Mode de
preparation des fluorures d'acides (pp. 243-244). Guntz, Sur un hydrure de lithium
(pp. 244-246).

i6e Annee. Tome iii. No. 2. Journal de Pharmacie et de Chimic.

(15th January, 1896.)
Franfois, Sur le protoiodure de mercure (pp. 49-53). Marie, T., Sur l'oxydation des acides
des graisses (pp. 53-55). Bishop, IV., Recherches sur la determination du degr6
d'oxydation des huiles (pp. 55-61). Meillere, G., Reactif molybdique (pp. 61-62).
Mouren, C, Synthese du methyleugenol (pp. 62-65). Lipinois, £., Sur une preparation
peu connue du chanvre indien (pp. 65-68).

i6e Annee. Tome iii. No. 3. (1st February, 1896.)

Bourquelot et Bertrand, G., Les ferments oxydants dans les champignons (pp. 97-102).
Riche, A., Conservation des peaux par les preparations arsenicales (pp. 102-106).
Meillere, G., Essai des acides nitrique et chlorhydrique (pp. 106-107). Marie, T., Sur
les proprieles des acides cerotique et melissique existant a fgtat libre dans la cire
d'abeilles (pp. 107- 1 11). Barthe, L., Analyse de concretions intestinales (pp. 111-113).
Rebiere, G., Sur un nouveau mode de dosage des benzoates alcalins (pp. 113-116).
Chicote, C, Une nouvelle falsification du safran (pp. 116-117). Fouquet, L., Sur un
calcul biliare contentant de l'acide stearique (pp. 117-119).

Band cclxxxix. Heft 3. Justus Liebig's Annalen der Chemie.
(7th January, 1896.)

Erlenmeyer, E., Ueber Phenyldihalogenpropionsiiuren, insbesondere ueber Phenylchlorjodpro-
pionsaure und einige Derivate derselben (pp. 259-285. ) Hantzsch, A. , und Wild, W. ,
Ueber Oxime aus a-halogenisirten Aldehyden, Ketonen und Sauren sowie ueber Oxim-
essigsauren (pp. 285-310). Smith, A., Ueber die Einwirkung von Hydrazin und von
Phenylhydrazin auf 1,4 Diketone (pp. 310-337). Wallach, O., Zur Kenntniss der Ter-
pene und der atherischen Oele (pp. 337-362). Beckmann, E., Untersuchungen in der
Kampherreihe (pp. 362-367). Beckmann, E., und Mehrlander, H., Zur Kenntniss der
Menthone (pp. 367-391).

Band ccxc. Heft 1. (28th January, 1896.)

Thiele, J. , und Heuser, A'., Ueber Hydrazinderivate der Isobuttersaure (pp. 1-43). Traubc,
J., Ueber das Molekulare Losungsvolumer und Molekularvolumen organischer Verbin-
dungen (pp. 43-122).

Jahrgang xxviii. ^ No. 19. Benchtc der Deutschen Cliemischen Gesellschaft.

(13th January, 1896.)

Jackson, C. L., und Ittner, M. H., Ueber Parabromdimetanitrotoluol und enige seiner Deri-
vate (pp. 3063-3066). Jackson, C. L., und Phiuney, J. J., Notiz ueber den Trinitrophenyl-
malonsaureester (pp. 3066-3068). Ladenburg, A., Ueber Lysidin (pp. 3068-3070). Schuf-
tan, A., Ueber ayu-Dimethyloxazol (pp. 3070-3072). Schneider, P., Ueber einige
Alkylderivate des Aethylendiamins (pp. 3072-3078). Lobry de Brtiyn, C. A., und van
Ehenstein, A. W., Einwirkung von Alkalien auf Kohlenhydrate. Wechselseitige Umset-
zung von Glucose, Fructose und Mannose in einander (pp. 3078-3082). Lobry de Bruyn,
C. A., Ueber die Ammoniakderivate der Kohlenhydrate (pp. 3082-3085). Lobry de Bruyn,
C. A., Ueber das freie Hydrazin (pp. 3085-3086). Lobry de Bruyn, C. A., Darstellung
und einige Eigenshaften des Hydrazinhydrats (pp. 3086-3087). Hjelt, £., Ueber den
Sogen. Ledumcampher (pp. 3087-3089). Mohlau, R., und Krubel, F., Ueber i-2-Dioxy- 3-
naphtoesaure (pp. 3089-3096). Mohlau, R., Ueber 2-3-Amidonaphtoesaure (pp. 3096-
3100). Mohlau, R., Zur Constitutionsfrage der 2'3-Oxynaphtoesaure und ihrer Derivate
(pp. 3100-3102). Landolt, H. , Ueber eine veranderte Form des Polarisationsapparates fur
Chemische Zwecke (pp. 3102-3104). Ladenburg, A., Erwiderung (pp. 3104-3106). Abel,
J., Ueber a-Naphtylpiperidin (3106-3111). Bookman, S., Ueber ;3- und y-Aethoxybutyl-
amin (pp. 3111-3121). Zincke, Th., Ueber eine neue Reihe von Chinonartigen Derivaten
(pp. 3121-3127). Wegscheider, R., Ueber die Esterbildung aus Saure und Alkohol (pp.

ENUMERATION OF TITLES. vn

3127-3129). Funk, R., Ueber den Schwefel- unci Kohlenstoff-gehalt des Zinks (pp. 3129-
3133). Darmstaedter, L., und Liffsch'atz, J., Beitrage zur Kenntniss der Zusammenset-
zung des Wollfettes (pp. 3133-3135). Fischer, E., und Lorenz, A., Synthese des Caffei'ns
(pp. 3135-3143). Koenigs, IV., Ersetzung von Hydroxyl in Chinaalkaloiden durch Was-
serstoff I. (pp. 3143-3148). Koenigs, IV., Ueber einige Dicarbonsauren von Piperidin-
basen (pp. 3148-3151). Besthorn, E., Ueber die Reduction der Chinolinsaure (pp. 3151-
3160). Paal, C, und Jdnicke, H., Ueber SulfaminsLiuren der aromatischen Reihe (pp.
3160-3167). Feist, F., und Arnstein, H., Ueber aromatische Homologue des Aethylen-
diamins (pp. 3167-3182). Engels, C, Quantitative Bestimmung von Mangan und Zinn
durch Elektrolyse (pp. 3182-3189). Drechsel, E., Ueber die Abschiedung des Lysins (pp.
3189-3191). Stobbe, H., Ueber die Condensation einfacher Ketone mit den Estern der
Bernsteinsiiure und Brenzweinsaure unter dem Einfluss von Natriumiithylat (pp. 3191-
3195). Meyer, V., Bemerkungen zur Abhandlung von Briihl : Ueber das Benzolproblem
(pp. 3195-3197). Meyer, V., Notizen der Geschicte der Esterbildung und Verseifung (pp.
3197-3201). Shukoff, A., Ueber eine neue Erscheinung bei der Esterbildung durch Wir-
kung von Alkohol und Salzsiiure auf aromatische Sliuren (pp. 3201-3203). Petrenko-Krit-
schenko, P., Ueber die sterische Hinderung Chemischer Reactionen (pp. 3203-3207).
Baum, F., Ueber den hindernden Einfluss orthostiindiger Methylgruppen auf die Bildung
der Oxime (pp. 3207-3212). Baum, F. , und Myer, V., Ueber die Zweimalige Einfuhrung
der Acetylgruppe in aromatische Kohlenwasserstoffe (pp. 3212-3215). Muhr, F., Ueber
eine Gesetzmiissigkeit bei der Spaltung aromatischer Ketonsauren (pp. 3215-3218). Gold-
schmidt, H., Ueber die Esterificirung durch alkoholische Salzsiiure (pp. 3218-3227).
Paal, C, und Ganser, F., Ueber die Einwirkung von Phenyl-i-cyanat auf organische
Aminosiiuren (pp. 3227-3234). Paal, C, und Kromschrbder, G., Ueber einige Derivate
des m-Dibrom-p-oxybenzaldehyds (pp. 3234-3237). Hantzsch, A., und Freese, H., Ueber
Thiodiazoverbindungen (pp. 3237-3252). Fischer, E., und Speier, A., Darstellung der
Ester (pp. 3252-3258). Herzig, J., und Meyer, H., Zur Kenntnis der Phtaleine (pp. 3258-
3262). Reformatzky, S., Neue Darstellungsmethode der aa- Dimethylglutarsaure aus der
entsprechenden Oxysaure (pp. 3262-3265). Slosson, E. E., Ueber die Einwirkung von
unterbromiger und unterchloriger Saure auf Saureanilide (pp. 3265-3271). Willstatter,
R., Ueber die Aufspaltung der Tropinsaure (pp. 3271-3292). Traube, J., Ausdehnung
der Gesetze von Gay-Lussac und Avogadro auf homogene Fliissigkeiten und feste Stoffe
(pp. 3292-3302).

Jahrgang xxix. No. 1. (27th January, 1896.)

Baeyer, A., Ortsbestimmungen in der Terpenreihe (pp. 3-27). Baeyer, A., Ortsbestimmungen
in der Terpenreihe (pp. 27-37). Friedlander, P., und Zinberg, S., Ueber einige 1-7
Derivate der Naphtalinreihe (Untersuchungen ueber isomere Naphtalinderivate II.) (pp.
37-42). Marckwald, IV., Ueber ein bequemes Verfahren zur Gewinnung der
Linksweinsaure (pp. 42-43). Marckwald, IV., Ueber die optisch activen a-Pipecoline
und das sogenannte Isopipecolin (pp. 43-52). Schutz, O., und Marckwald, IV., Ueber
optisch active Valeriansiiure (pp. 52-59). Miller, W. v., und Plbchl, J., Ueber
Thio-aldolanilin undAldehydgrun (pp. 59-62). Munch, G., Ueber Amidoxylisobuttersaure
(pp. 62-65). Vongerichten, E., Zur Kenntniss des Morphins (pp. 65-69). Kahlbaum, G.
IV. A., Der sogenannte Liebeg' sche Kiihl-apparat (pp. 69-71). Kahlbaum, G. IV. A.,
Xormalsiederohr (pp. 71-73). Kaufmann, V., Ueber Biphenylenediphenylather (pp.
73-76). Niementowski, St., Ueber das Chinacridin (pp. 76-84). Piutti, A., Ueber die
Einwirkung der Bernsteinsaure auf das p-Amido-phenol und dessen Aether (pp. 84-87).
Scholt, R., und Landsteiner, K., Reduction der Pseudonitrole zu Ketoximen (pp. 87-90).
Born, G., Zur Kenntniss der Pseudonitrole und Dialkyldinitromethane (pp. 90-102).
Bamberger, E., Ueber die Einwirkung des Nitrosobenzols auf Amidoverbindunger
(pp. 102-105). Goldschmidt, C, Ueber die Einwirkung von Ammoniak auf den
Benzoylessigester (pp. 105-106). Buchner, E. , Ueber Pseudophenylessigsiiure (pp. 106-
110). Hjelt, E., Ueber die Verseifung der alkylsubstituirten Malonsaureester (pp. 110-111).
Weiler, M. , Ueber die Enstehung von p-Tolylphenylmethan aus p-Bromtoluol und
Natrium (pp. 111-115). Weiler, M., Ueber die bei der Einwirkung von Natrium auf
Brombenzol entstehenden hochmolekularen Kohlenwasserstoffe (pp. 115-119). Tiemann,
F., Zur Terpen- und Campherfrage (pp. 119-131). Bistrzycki, A., und Nencki, K., Notiz
zur Constitution der Phenol-phtalein-Alkalisalz (pp. 131-133). IValden, P., Ueber die

vin SCIENCE PROGRESS.

gegenseitige Umwandlung optischer Antipoden (pp. 133-138). Herzig, J. , und Meyer,
H., Nachtrag zur der Abhandlung : Zur Kenntniss der Phtalei'ne (pp. 138-139). Warner,
E., Beitrage zur Beurtheilung der Isomerie der Trithioaldehyde (pp. 139-160). Gabriel,
S., und Stelzner, R., Ueber o- Nitrobenzylmercaptan (pp. 160-165). Kiihling, O., Ueber
den Ersatz der Isodiazogruppe durch cyclische Reste. II (pp. 165-169). Gundlich, C,
und Knoevenagel, E. , Ueber Derivate des Dihydrochlorbenzols und ihre Dehydrirung
(pp. 169-172). Knoevenagel, E. , Ueber eine Darstellungsweise des Benzylidenacetessigesters
(pp. 172-174). Liebermann, C. , Zur Tautomeric der o-Aldehydsauren (pp. 174-183).
Liebermann, C, Ueber den Aufbau eines isomeren Narcotins (pp. 183-187). Nencki, K.,
Ueber die Einwirkung von o-Aldehydosauren auf Chinaldin bei Gegenwart von Chlorzink
(pp. 187-190).

Jahrgang xxix. No. 2. (10th February, 1896.)

Schunck, E., und Marchlewski , L., Zur Kenntniss des Isatins (pp. 194-203). Von Lipp-
mann, E. O., Bemerkung zur Frage ueber die Ursache der Birotation (pp. 203-204).
Scheitel, A., Darstellung der Salze der Platincyan-Wasserstoffsaure Pt(CN)4H2.(pp.
204-205). Fischer, E., Neue Bildungsweise der Oxazole (pp. 205-214). Zelinsky, N.,
und Reformatzky, A., III. Untersuchungen in der Hexamethylenreihe (Synthese des
Nononaphtens) (pp. 214-216). Heffter, A., Ueber Cacteen-alkaloi'de (pp. 216-228). Kerp,
W., Ueber Diphenylenketon und Pseudo-Diphenylenketon (pp. 228-233). Bablich, A.,
und v. Kostanecki, St., Ueber Oxybenzalacetophenone (pp. 233-237). V. Kostanecki, St.,
und Tambor /. , Ueber a-Cumaryl-Phenylketon (pp. 237-240). Cornelson, A., und v.
Kostanecki, St., Zur Einwirkung der Aldehyde auf Ketone (pp. 240-244). V. Kostanecki ,
St. , und Oppelt, E. , Ueber einige Derivate des 2-Oxy-benzalacetophenons (pp. 244-249).
Knorr, L., Ueber das Pyrazolon (pp. 249-260). Bleier, O., Ueber gasanalytische
Apparate (pp. 260-265). Schopf, M., Zur Constitutionsfrage der 2'3-Oxynaphtoesaure
(pp. 265-270). Schall, C. , Ueber y-Carbodiphenylimid (pp. 270-272). Bamberger, E., und
Kraus, £., Ueber Thiodiazoverbindungen (pp. 272-287). Schraube, C, und Fritsch, M.,
Wanderungen der Diazogruppen (pp. 287-295). Erlenmcyer, E. , Zur Kenntniss der
Diphenyloxathylaminbasen (pp. 295-298). Schiff, H. , Biuret-reactionen (pp. 298-303).
Gabriel, S., und Stelzner, R., Ueber (B, 3-) Methylindazol (pp. 303-310). Klages, A..
Ueber einige Derivate des m-Xylols (pp. 310-314). /linger, E., und Klages, A., Ueber
den Abbau des Menthols (314-318).

Band liii. No. 1. Journal fiir praktische Chemie. (3rd January, 1896.)

Otto, R., Ueber das Verhalten des Stilbendibromids und der Tolandibromide gegen benzol-
sulfinsaures Natrium und Natriumphenylmercaptid (1-19). Rosdalsky, G., Ueber
Abkommlinge des Piperazins (pp. 19-25). Clans, Ad., Meta-para- und Para-ana-
Dibromchinolin (pp. 25-39). Clans, Ad., und Huth, M., Zur Kenntniss der Resorcin-
Ketone (pp. 39-42). Erdmann, H., und Huth, P., Zur Kenntniss des Rhodinols oder
Geraniols (pp. 42-47). Vaubel, IV, Ueber den Zusammenhang zwischen Farbe und
Constitution der Triphenylmethanfarbstoffe (pp. 47-48).

Band xi. Heft 2 und 3. Zeitschvift fiir Anorganische Chemie. (25th Jan., 1896.)

Hempel, W., und Thiele, H., Eine Atomgewichts bestimmung des Kobalts (pp. 73-106).
Piccini, A., Ueber die Alaune des Vanadintrioxydes. I. (pp. 106-116). Peters, P.,
Einige Produkte, die durch Einwirkung von Blei und von Kaliumnitrit auf Bleinitrat
entstehen (pp. 116- 160). Spring, IV., Ueber den Einfluss der Zeit Auf das Zusammen-
schweissen geprcsster Kreide (pp. 160-165). Kiister, P. IV., Ueber die Reaktion
zwischen Ferrisalzen und Jodiden in wasseriger Losung (pp. 165-175). Rosenheim, A.,
Ueber die Einwirkung anorganischer metallsauren auf organische sauren. II. (pp.
17S-223).

Band xix. Heft 1. Zeitschvift fiir Physikalische Chemie. (28th Jan., 1896.)
Storch, L., Ueber den Verlauf chemischer Reaktionen bei Gasen (pp. 1-13). Storch, L., Ueber
das Verdiinnungsgesetz der Elektrolyte (pp. 13-20). Eder, J. M., Bemerkungen zur
Herrn C. Bohns Abhandlung : , " Ueber Flammen und leuchtende Gase" (pp. 20-25).
Mond, L., Raynsay, IV., und Shields, /., Ueber die Okklusion von Sauerstoff und Was-
serstoff durch Platinschwarz I. (pp. 25-63). Wildermann, M., Ueber die scheinbare und

ENUMERATION OF TITLES. ix

wahre Gefriertemperatur und die Gefriermethoden (pp. 63-94). Ratz, F., Ueber die Die-
lektrizitatskonstante von Fliissigkeiten in ihrer Abhangigkeit von Temperatur und Druck
(pp. 94-113). Nasini, R., und Gennari, G., Anomalien in der Rotationsdispersion der
Apfelsaure (pp. 113-130). Gennari, G., Ueber die Rotationsdispersion des Nikotins und
seiner Salze (pp. 130-135). Miiller-Erziack, W., Die durch aussern Feuchtigkeitsdruck
gemessene Zersetzungsspannung wasserhaltiger Salze und die Konstitution des gebun-
denen Wassers (pp. 135-155J. V. Schneider, B., Ueber die Schmelzpunkte einiger
organischer Verbindungen (pp. 155-191).

Anno xxv. Vol. 2. Fascicolo 6. Gazzetta Chemica Italiana. (14th Jan., 1896.)

Leone, T., Sulla ricerca dell' acido nitrico per indiziare l'anacquamento dei vini (pp. 433-461).
Francesconi, L., Acido santonico e suoi derivati (pp. 461-478). Tarugi, N., Esclusione
del solfuro ammonico (40 gruppo) dall' analisi qualitativa (pp. 478-481). Rebufatt, O.,
Teorie ed esperinienti sui cementi idraulici (pp. 481-494). A?igeli, A., e Rimini, £.,
Sopra l'esodiazoacetofenone (pp. 494-497). Ptirgotti, A., Azione dell' idrato d'idrazina
sull' etere etilico di qualche nitrofenolo e sintesi della 2, 4, 6-trinitro metaetossi feniledrazina
(pp. 497-505). Cossa, A., Sui composti di platosomonodiammina (pp. 505-508). Nasi/ii,
R., e Anderline, F., Ricerca dell'argo nelle emanazioni terrestri I. Gas delle terme di
Abano (pp. 50S-509). Piatti, A., Azione dell' acido succinico sopra il p-amidofenolo ed i
suoi eteri (pp. 509-518). Piutti, A., Azione del jodio sopra immidi ed immidi sostituite
(pp. 518-527). Castellaneta, £., Azione degli acidi ossalico e malonico sopra il
p-amidofenol ed i soui eteri (pp. 527-542). Piccini, A., Sugli allumi di sesquiossido di
titanio (pp. 542-543).

A*

APPENDIX I.

NOTICES OF BOOKS.

Die Spiele der Thiere. By Karl Groos. Jena: G. Fischer, 1896. Pp. xvi. , 359.

The chief point which is worked out in this book is that animal play depends on a
deeply planted instinct of the greatest importance in the struggle for existence. Spencer's view
that play is the expression of overflow of energy is held to be only a small part of the truth.
Play is regarded as the instinctive performance, without real cause, of actions resembling those
useful in the actual struggle for life. Superfluous energy is the most favourable condition for
play, but the author points out that the impulse to play is so strong that animals will react to a
stimulus to play even when in an exhausted condition.

The second chapter contains a good account of the views which have been held on the
subject of instinct, the author's own position being very close to that of Weismann. Play being
regarded as an instinct, the play of young animals is naturally most fully considered. The im-
portance of play is rated so highly that the author supposes that "youth owes its existence to
the necessity for play". In the next two chapters, in which the games of animals are con-
sidered in detail, the author's views are illustrated by copious examples drawn from very wide
sources, but chiefly from the accounts of those who have observed animals in a state of nature.
One of the most quoted authors in this respect is Hudson. The simplest kind of play is called
"experimenting," and this term is employed for the actions of young animals, by means of
which they obtain command over their own movements and over external objects. Under the
heading of play of movement are included most of the examples quoted by Spencer in support
of his theory. Hunting and fighting games are fully considered, and they give strong support
to the author's view. In considering such play as that of a cat with a caught mouse, strong
objection is made to Romanes' view that animals delight in torture for torture's sake ; such
play is rather regarded as instinctive activity adapted to improve skill. Instances are given in
which building and nursing appear to have occurred in play. Imitation games are considered,
and imitation is regarded as an instinct closely associated with the play instinct.

The performances of courtships are considered separately, differing from other kinds of
play in that they have a real occasion. The subject of sexual selection is fully discussed. The
author is sceptical on the question of conscious choice by the female, and he thinks that there
is distinct evidence that pairing takes place before the courtship performances begin. He re-
gards it as necessary for the preservation of the species that there should be some restraint of
the sexual act, and he supposes that this restraint is provided by instinctive coyness of the
female, and that the performances are carried out in order to overcome this coyness by pro.
ducing sexual excitement ; coquetry is the result of the struggle of two opposed instincts. A
full account is given of the various forms which these performances may take, and instances
are given in which they have been observed in young animals.

In the final chapter the psychology of play is considered. The games of young animals
are held to be purely instinctive, and their only mental accompaniment to be the pleasure
attending the satisfaction of an instinct. In the adult animal it is believed that play is often
accompanied by consciousness of the unreal nature of the activity, the chief element in this
consciousness being the pleasure of power. Instances of dissimulation in animals are quoted
in support of the existence of consciousness of sham-occupation. In conclusion, the relation of
animal play to the various forms of art is dealt with, and this part of the subject will no doubt
be more fully treated in another work on human play which is promised by the author.

Text-book of the Embryology of Invertebrates. By E. Korschelt and K. Heider. Translation
into English by E. L. Mark and W. Mc. M. Woodworth, with additions by the Authors
and Translators. Part I. London : Swan Sonnenschein & Co. , Limited. New York :
Macmillan & Co. , 1895.

This volume of 466 pp. , with 225 illustrations, has been eagerly awaited. The original
is too familiar to those who read German to need comment here ; suffice it to say that it deals
in a lucid manner with the development of the Invertebrata, including the Enteropneusta and
Rotatoria, with the exception of the Mollusca, Brachiostoma, and Arthropoda. Prof. Mark's

B

xii SCIENCE PROGRESS.

previous translations are so well known, and the work which for years has appeared under his
direction in the Bull. Mus. Comp. Zool. at Harvard College has become so famous for the
thoroughness of its bibliographical department, that the success of the present venture seemed
assured in his hands.

The original is certainly the best general treatise on Embryology which has appeared
since Balfour's, if indeed it is not in some respects preferable to that. With respect to
the share taken by the translators in bringing it up to date, comparison arises with
the senior translator's rendering of Hertwig's Text-book of Embryology, in which a
similar resolve was made but very inefficiently carried out. Not so here ; and in the
selection of new matter, a wise discretion has been exercised in the presentation of novelties to
the student mind, to wit, in the treatment of those observations tending towards the overthrow
of the germ-layer theory. We note that clue regard has been paid to the various modes of
asexual reproduction and regeneration, a feature not always met with in works on Embryo-
logy ; but, conversely, we regret that Chun's Dissogonie has not received the attention it
deserves in the Chapter on the Ctenophora. And it is a distinctly healthy sign to read in a
text-book of pure Embryology, apropos of Semon's " Pentactula " stage in Echinoderm develop-
ment and a discussion of its possible bearings on Phylogany, that it seems " more justifiable to
search for the ancestral forms of the Echinodermata among the existing material which is
offered us by Palaeontology ".

Of the success of the translation and of the future of the book there can be no doubt. It
is clear in style and in get up. All has been done with a due sense of proportion, and the few
errors we have detected are such as will be self-evident to the intelligent reader. We can
confidently recommend the work as the most generally serviceable on the subject in the
English tongue.

The translators remark in their preface that they have been " compelled by the pressure
of other duties to relinquish to others the task " of translation of the two remaining parts of
the work. In this they have become notorious, for, loyal to an earlier suggestion of the senior
translator, they have rendered "anlage" as "fundament"! The publishers announce that
the translation will be continued by Dr. H. J. Campbell, a gentleman who has served them
in a similar capacity on more than one occasion. We would remind him that in respect to the
general translation here set before him he has an example which he may well emulate, and
express the hope that in the interests of English he will not allow the afore-mentioned extra-
ordinary misuse of so commonplace a word to continue.

Introduction to the Study of Fungi, their Organography, Classification, and Distribution for
the use of Collectors. By M. C. Cooke, M.A., LL.D. , A. L.S. London: Adam &
Charles Black.

Perhaps there is no group of plants more bewildering to the beginner than that of the
Fungi. The number of known species is enormous, probably more than 40,000, and the
frequent occurrence of polymorphism serves considerably to complicate the task of under-
standing their mutual relationships. Most of the existing text- and hand-books, even though
estimable enough in their way, only produce a feeling of discouragement in the mind of the
student, since they practically presuppose a degree of acquaintance with the general forms of
the plants such as the reader in most cases does not possess. Hence he has either to greatly
extend the scope of his reading by referring to original papers and figures, or, too commonly,
he is contented with merely "getting up" special facts about an organism of whose general
character he does not possess the remotest idea.

The great merit of Dr. Cooke*s book lies in the fact that it contains a good deal of
description of entire plants. Probably no one possesses a more extensive knowledge of the
external characters of Fungi than the author, and his account is frequently enlivened with
interesting details of habit and mode of life. He divides the work up into three main sections,
Organography, Classification, and Distribution, and in an appendix gives useful hints as to
collecting and preserving specimens.

The subject of Organography is dealt with rather from the standpoint of the systematist
than from that of the comparative morphologist, and although this method of treatment is of
necessity somewhat formal the student will find that it possesses practical advantages of its
own, inasmuch as it provides a useful key with which to unlock the vast storehouse of facts
buried in the more purely systematic treatises. Naturally, there are several points on which
there will be differences of opinion between the author and his readers, and the records of
certain alleged observations whose accuracy has never been admitted by persons most qualified
to judge, might well have been omitted. Probably, too, many will dissent from the author's

NOTICES OF BOOKS. xm

opinion that in " Hymenomycetal Fungi really parasitic species are almost if not wholly
unknown ".

In the introduction to the section on Classification, a sketch of the Brefeldian system is
given, though it is not adhered to by Dr. Cooke in the subsequent chapters. We notice that
the author still apparently retains the opinion that Lichens are to be regarded as a group dis-
tinct from Fungi on the one hand and from Algae on the other, but no new arguments are
brought forward to support a position which has been long ago abandoned by nearly all
botanists.

Speaking generally, one. rather misses in these chapters the feeling a real and natural
relationship existing between the different groups, and in some instances, as in the Uredineue
and Ustilagineae, there is no effort made to trace it. This is especially disappointing when one
recollects the brilliant expositions of Brefeld and his disciples on these questions. But not-
withstanding this defect — for as such we must regard it — there is a great deal of valuable
matter in these pages which will not be readily found elsewhere.

The concluding section on Distribution contains some interesting facts and generalisations,
and statistics are given as to the relative proportions in which the various groups are scattered
over the earth's surface. Thus amongst the Hymenomycetes it would appear that the more
fleshy species are chiefly restricted to temperate and cold climates, whilst the tough and
leathery forms are more especially characteristic of the tropical regions.

The book is well illustrated with figures, and the copious bibliographies appended to the
chapters greatly add to the value of a work which deserves to be widely appreciated, not only
by " Collectors,"" for whose use it was more especially designed, but by all who are interested
in these lower orders of plants.

Untersiichungcn iiber die Starkekbrner. By Dr. A. Meyer. Jena: Fischer, 1895.

This is one of the most important and valuable monographs that have recently been
published, treating as it does of a somewhat small section of botanical research, which has
nevertheless been the subject of much controversy, and has been the subject of investigation
and speculation by many writers of great technical skill and critical acumen. It includes a
summary of the researches of previous observers, and is enriched by independent observations
of the author.

The starch grain seems at first sight to offer but little scope for speculation, yet upon its
structure many points of great importance hang, which touch indeed the physical construction
of protoplasm itself, and that of the many organised structures derived from it.

Dr. Meyer treats very carefully of the chemistry and physics of the starch grain as well as
of its biological peculiarities. He considers it to consist of at least two different bodies, which
he calls amylases, both of which are crystalline, though one of them cannot be made form
isolated crystals. Besides these other substances sometimes occur, which are also carbohy-
drates, but which are only found when the grains have been somewhat modified. It is a pity,
perhaps, that he has selected the term amylase for these two constituents, as the termination
-ose is so generally in use for sugars of various composition.

Dr. Meyer holds that the crystalline substance is in the form of fine needles, to which he
gives the name trichiles, and these are arranged in the grain in a radiating form, producing
sphere-crystals, which are differently constituted in the several layers of the grain. The various
physical properties which the latter presents are of course consistent with this view of its structure.
The absorption of water which can so easily be brought about by the action of weak alkalis, etc. ,
is discussed at some length. In the author's opinion it is brought about by the actual taking
up of water by the crystalline trichites, and not by its intercalation between them ; we have
therefore a view opposed to the older theory of the micellae put forward so many years ago by
Naegeli. Dr. Meyer does not, however, deny the possibility of water being taken up and held
by whatever lies between the crystals.

The fate of the starch grain after its formation, the action of diastase upon it, and the
many possible reactions leading to the appearance of the various dextrins are also very fully
discussed. This section of the work in particular will be of great interest to all students of
vegetable physiology.

In the chapters devoted to the formation and growth of the starch grain some new views
are advanced which will perhaps not be readily accepted by other workers in this field. He
supports very strongly Schimper's views of the action of the leucoplast, but he states that the
formation of the grain is always inside the corpuscle. Though this has long been recognised
as happening sometimes, it seems difficult to reconcile certain cases of not uncommon occur-

xiv SCIENCE PROGRESS.

rence with it. Dr. Meyer, however, thinks the observations on which the view of excretion of
starch substance beyond the plastid is based are defective, and that a thin layer of the latter
always extends around the incipient and growing grain, although it needs very careful
staining by approved methods to make it visible. He further extends the amyloplastic powers
of the leucoplast and the chlorophyll grain to certain chromoplasts.

Besides these researches based upon the normal grains as commonly seen, the book con-
tains some very valuable information upon the changes which the starch grain shows under
many varied conditions, the differences noticeable at different seasons, and the alterations in it
in the various organs of many different plants, taken from a very wide range in the vegetable
kingdom. Many ingenious experiments are narrated bearing on many of these points. They
are, however, of less general interest and indeed of less importance than the points of origin,
structure and fate which have already been alluded to.

The work will have a great fascination for many workers in the field of vegetable physio-
logy. It is a pity that the language in which it is written will cause it to be less generally
useful to the English reader than its importance warrants.

APPENDIX II.
CHEMICAL LITERATURE FOR FEBRUARY, 1896.

Vol. i. No. 3. American Journal of Science. (March, 1896.)

Gooch, F. A., and Peirce, A. IV., Method for the Separation of Selenium from Tellurium
based upon the difference in volatility of the Bromides ( pp. 181-186). Adams, F. D., and
Harrington, B. J., New Alkali Hornblende and a titaniferous Andradite from the
Nepheline-Syenite of Dungannon, Hastings County, Ontario (pp. 210-219). Penfield, S.
L., and Pratt, J. H., Occurrence of Thaumasite at West Paterson, New Jersey (pp. 229-
234)-

Vol. xviii. No. 3. Journal of the American Chemical Society. (March, 1896.)

Clarke, F. IV., Third Annual Report of Committee on Atomic Weights. Results published
during 1895 (pp. 197-214). Johnson, S. IV., Composition of Wood Gum (pp. 214-223).
Blair, A. A., Method for the Determination of Carbon in Steel (pp. 223-227). Hopkins,
C. G. , A New Safety Distillation Tube for Rapid Work in Nitrogen Determinations (pp.
227-228). Stone, G. C, Remarks on Mr. Auchy's Paper on the Volumetric Determination
of Manganese (pp. 228-230). Stone, G. C, Probable Production of Permanganate by
Direct Combustion of Metallic Manganese (pp. 230-231). Squibb, E. R., The Manu-
facture of Acetone and of Acetone-Chloroform from Acetic Acid (pp. 231-247). Prescott,
A. B., and Baer, S. H., Pyridine Alkyl Hydroxides (pp. 247-251). Andrews, /.., On the
Reduction of Sulphuric Acid by Copper, as a Function of the Temperature (pp. 251-254).
Wait, C. E., The Oxidation of Silver (pp. 254-259). Wainwright, J. H., The Determi-
nation of the Solid Fat in Artificial Mixtures of Vegetable and Animal Fats and Oils (pp.
259-264). Hazen, A., The Measurement of the Colours of Natural Waters (pp. 264-275).
Linton, L. A., Technical Analysis of Asphaltum, 2 (pp. 275-283).

Vol. xviii. No. 2. American Chemical Journal. (February, 1896.)

Wheeler, H. S., and Walden, P. T., On Halogen Addition- Products of the Anilides (pp. 85-
90). Hansen, I., and Norris, J. F., The Action of the Halogens on the Methylamines
(pp. 90-95). De Chalmot, G. , On Silicides (pp. 95-96). Morris, R. S. , and Cottrell, F.
G., Some of the Properties of Liquid Hydriodic Acid (pp. 96-105). Kastle, J. H, and
Bullock, J. H., On the Preparation of Hydrobromic and Hydriodic Acid (pp. 105-111).
Jackson, C. /.., and Warren, II'. H. , Turmerol (pp. 111-117). Jackson, C. L., and
Dunlap, F. L., Certain Bromine Derivatives of Resorcine (pp. 117-133). Jackson, C. L.,
and Sock, C. A., Trinitrophenylmalonic Ester (pp. 133-141). Mabery, C. F., and Byerley,
J. //. , The Artificial Production of Asphalt from Petroleum (pp. 141-150). Re/nsen, /.,
Hart/nan, R. N., and Muckenfuss, A. M., On the Action of Phosphorus Pentachloride
on Parasulphaminebenzoic Acid (pp. 150-178).

Vol. xxi. No. 240. The Analyst. (March, 1896.)

Blount, B., The Determination of Oxygen in Commercial Copper (pp. 57-62). Cribb, C. H., A
New Form of Carbonic Acid Apparatus (pp. 62-64).

Vol. lxix. No. 400. Journal of the Chemical Society. (March, 1896.)

Henderson, J., Action of Sugars on Ammoniacal Silver Nitrate (pp. 145-154). Tilden, W. A.,
and Barnett, R. E. , The Molecular Weight and Formula of Phosphoric Anhydride and
of Metaphosphoric Acid (pp. 154-161). Bentley, W. H., Haworth, E., and Perkin, W.
H., Jun., On 7-Phenoxy-Derivatives of Malonic Acid and Acetic Acid, and Various Com-
pounds used in the Synthesis of these Acids (pp. 161-175). Haworth, E., and Perkin, W.
H., Jun., Note on the Preparation of Glycol (pp. 175-177). Luxmoore, C. A/., The

xvi SCIENCE PROGRESS.

Oximes of Benzaldehyde and their Derivatives (pp. 177-193). Walker, J. , and Appleyard,
J. R., Transformation of the Alkylammonium Cyanates into the corresponding Ureas (pp.
193-206). Perkin, A. G., Luteolin, I. (pp. 206-212). Hutchinson, A., and Pollard, IV.,
Lead Tetracetate and the Plumbic Salts (pp. 212-226). Lewes, V. B., The Acetylene
Theory of Luminosity (pp. 226-243).

Vol. xv. No. 2. Journal of the Society of Chemical Industry. (29th Feb., 1896.)

Lovibond, J. W., The Effect of Lime Salts on Hop Infusions (pp. 71-75). Reid, W. P., The
Manufacture of Linoleum (pp. 75-79). Irwin, IV., The Effect of Heat on the Illuminat-
ing Power of Coal-Gas. Its Relation to the Theory of Flame (pp. 80-81). Davis, G. E.,
Photography by the Rontgen Rays (p. 82). Barnes, J. , On the Estimation of Organic
Matter by Means of Chromic Acid (pp. 82-84). Archbutt, L., Note on the Ignition of
Sawdust by Nitric Acid (pp. 84-85). Archbutt, L. , Note on an Experiment made to
Determine the Pressure of Ether and some other Volatile Liquids in Closed Vessels (pp.
85-86). Cohen, J. B., and Russell, G. H., The Combustion of Coal and Gas in House
Fires (pp. 86-90). Mackey, McD. IV. , Apparatus for the Determination of the Relative
Liability to Spontaneous Combustion of Oils spread on Cotton Wool (pp. 90-91). Dott,
D. B. , Opium Assay (pp. 91-94). Gane, E. H. , The Determination of Caffeine in Tea
(pp. 95-96). Edwards, H. IV., Bessemerizing Nickel Matte (pp. 96-99). Peacock, S.,
American Phosphates in 1895 (p. 99).

Vol. xli. No. 250. Philosophical Magazine and Journal of Science.

(March, 1896.)

Ncrnst, II'., and Abegg, R., On the Freezing-points of Dilute Solutions (pp. 96-199).

Tome vii. Annates de Chimie et de Physique. (March, 1896.)

Perrcau, P., Etude experimentale de la dispersion et de la refraction des gaz (pp. 289-348).
Sabatier, P., et Senderens, J. B. , Recherches sur les oxydes de l'azote, oxyde azotique,
oxyde azoteux, peroxyde d'azote (pp. 348-416). Lescoeur, H., Recherches sur la dissocia-
tion des hydrates salins et des composes analogues (pp. 416-432).

Tomes xv.-xvi. No. 4. Bulletin de la Societe Chimique de Paris.
(20th February, 1896.)

Guve, P. A., et Chavanne, L., Etude sur la dissymefrie moleculaire : Recherches sur le pouvoir
rotatoire des corps actifs homologues (pp. 177-195). Tanret, C, Sur les modifications
molcculaires et la multirotation des sucres (pp. 195-205). Tassily, Sur les iodures cris-
tallis£s de strontium et de calcium (pp. 205-206). Varet, R. , Recherches sur les cyanures
de lithium, de magnesium, de cuivre (pp. 206-208). Senderens, J. B., Nouvelles recherches
sur les precipitations mefalliques (pp. 208-221). Iovitschlch, A/., Contribution a la
connaissance de la stereoisomerie que prtfsente Tether isonitrosoacefylacetique (pp. 221-
227). Arth, G., Action de I'isocyanate de ph^nyle sur l'acide •y-pimelique deYive1 du
menthol (pp. 227-229). Reverdin, F., et Ka.uffm.an, H., Sur quelques produits de
substitution des carbonates et phosphates d'a et de £-naphtyle et sur la preparation du
chloronaphtol C](JH6OH. CI. (1.4) et du bromo naphtol C10H6OH. Br (1.4) (pp. 229-235).
Bietrix, A., Sur une matiere colorante derived de l'acide dibromogallique (pp. 235-236).
Lasne, //., Sur le dosage de 1' aluminium dans les phosphates (iii.) (pp. 237-248). Bechamp,
A., Sur les alterations spontanees du lait et sur celles que la cuisson lui fait subir (pp.
248-272).

Tomes xv.-xvi. No. 5. (5th March, 1896.)

Tassilly, Appareil pour filtrer ou essorer les corps alteYables a Fair (pp. 274-275). Guye, P.,
et Chavanne, L. , Etude sur la dissymetrie moleculaire : Recherches sur le pouvoir rotatoire
des corps actifs homologues (pp. 275-305). Guye, P. A., et Jordan, C, Formule sim-
plified pour calculer les variations dedensite des liquides avec la temperature (pp. 306-309).
Thomas, V. , Action du peroxyde d'azote sur les sels halogenes d'etain (persels) (pp. 309-

ENUMERATION OF TITLES. xvn

315). Racoura, A., Sur un nouvel acide du chrome, l'hydrate sulfochromique (pp. 315-
321). Trillat, A., Preparation des amines de la serie grasse (pp. 321-322). Perrir, G.,
Sur la propylnaphtyketone 0 (pp. 322-324). Haller, A., Synthese partielle du camphre
(pp. 324-327). Rosenstiehl, A., Sur quelques reactions propres aux fuchsines et aux
carbinols amides (pp. 327-330).

Tome cxxii. No. 6. Comptes Rendus hebdomadaires de V Academic des Sciences.

(10th February, 1896.)

Moissan, H., Etude du carbure d'uranium (pp. 274-280). Haller, A., Sur la campholide,
produit de reduction de l'anhydride camphorique (pp. 293-298). Vigouroux, Sur le
siliciure de cuivre (pp. 318-320). Besson, A., Sur le chlorobromure et le bromure de
thionyle (pp. 320-322). Granger, A., Sur un sulfophosphure d'etain cristallise' (pp. 322-
323). Tassilly, Oxyiodures de zinc (pp. 323-325). Bridle, R. , Methode pour determiner
la purete des beurres au moyen de la density (pp. 325-326).

Tome cxxii. No. 7. (17th February, 1896.)

Moissan, H., Preparation et propri^tes du carbure de cerium (pp. 357-262). Moissan, H., Sur
le carbure de lithium (pp. 362-364). Engel, R., et Bernard, J., Sur un proc£de rapide de
dosage de l'arsenic (pp. 390-393). Barbier, P.,et Bouveault, L., Synthese partielle de
l'acide geranique ; constitution du temonol et du lemonal (pp. 393-395). Gassmann, C,
Sur quelques derives de l'eugenol (pp. 395-398). Schloesing, T.,Jils, Sur la composition du
grisou (pp. 398-401).

Tome cxxii. No. 8. (24th February, 1896.)

Moissan, H., Sur le carbure de manganese (pp. 421-424). Moissan, H., Etude des borures
de nickel et de cobalt (pp. 424-426). Gautier, A., Sur le dosage de l'arsenic (pp. 426-
428). Haller, A., Sur la transformation de l'acide camphorique droit en camphre droit ;
synthese partielle du camphre (pp. 446-449). Carnot, A., Analyse, par les precedes
volumetriques, d'un melange de chlorures, d'hypochlorites et de chlorates (pp. 449-452).
Carnot, A., Analyse d'un melange de chlorures, de chlorate et de perchlorates (pp. 452-
454). Besson, A., Action de quelques composes hydrogenes sur le chlorure de sulfuryle
(pp. 461-469). Barillot, £.,Sur le rendement des diverses essences de bois en charbon,
alcool methylique et acide acelique (pp. 469-471). Chesneau, Sur la temperature des
etincelles produites par l'uranium (pp. 471-473). Marie, C, et Marquis, R., Sur un
nouveau mode de formation des nitroprussiates (pp. 473-474). Bauge, G., Sur un
carbonate chromeux ammoniacal cristallise! (pp. 474-477). Monren, C, Sur la veratry-
lamine (pp. 477-480). Rivals, P., Etude thermochimique de l'acide orthochlor-
benzoi'que et de quelques-uns de ses derives (pp. 480-482). Trillal, A., Trans-
formation de la solution de formaldehyde en vapeurs pour la desinfection (pp. 482-
483).

Tome cxxii. No. 9. (2nd March, 1896.)

Barbier, P., et Bouveault, Extraction du rhodinol, de l'essence de pelargonium et de l'essence
de roses ; identite de ces deux alcools (pp. 529-531). Combes, C, Sur la preparation du
silicichloroforme, du silicibromoforme et sur quelques derives du triphenyl-silico-protane
(PP- S3r-533)- Charon, E., Oxydation de l'aldehyde crotonique (pp. 533-535).

i6e Annee. Tome iii. No. 4. Journal de Pharmacie et de Chimie.
(15th February, 1896.)

Cazeneuve, P., Note sur un nouvel outillage pour conserver les viandes par cuisson et elimina-
tion d'air (pp. 169- 171). Marie, T., Ethers glyceriques des acides cerotique et meiissique
(pp. 171-177). Bourquelot, E., et Bertrand, G. , Sur la coloration des tissus et du sue de
certains champignons au contact de l'air (pp. 177-182). Barthe, L., L'oxycyanure de
mercure (pp. 182-184).

i6e Annee. Tome iii. No. 5. (1st March, 1896.)

Colson, A., Sur un type d'allumettes non toxiques (pp. 225-228). Gorges, Dosage de l'iode
dans 1'huile de foie de morue (pp. 228-229). Francois, M. , Sur le protoiodure de mercure

B*

xviii SCIENCE PROGRESS.

(pp. 229-233). Gerard, £., Sur le dedoublement de l'Amygdaline dans l'economie (pp.
233-236). La/ay, L. , Quelques faits relatifs a la pharmacologie du benzoate de soude (pp.
236-242).

Tome xxvii. No. 9. Journal de la Societe Physico-Chimiquc Russe.

Kischner, N., Sur les amines et les hydrazines de la seYie polymethylenique (pp. 521-553).
Selivanoff, T., Action des acides hypochloreux et hypobromeaux sur l'iodure de potassium
(pp. 553-568). Reformatsky, S., et Pleskonosoff, W., Action du zinc sur Tether bromoiso-
butyrique en presence de l'ac^tone (pp. 568-577). Tichvinsky, M. , Benzylrosinduline et ben-
zylrosindulone (pp. 577-584). Godlevsky, /., Oxydation du limonene ; Wagner, G. , M^thodes
pour determiner la structure des olefines ; Wagner, G., Sur le formation simultanee des
Others nitreux et des combinaisons nitrees ; Ertchikoffsky, Action de l'acide acetique sur le
pinene eu presence du chlorure de zinc ; Ginsberg, A., La dehydratation du trioxyhexa-
hydrocymene; Petrenko-Kritchenko, Action de la phenylhydrazine sur les ethers
acetodicarboniques ; Charitschkoff, A'., Sur la naphte de l'ile de Tcheleken ; Jakovkine,
A., Sur la division d'une substance entre deux dissolvants ; Reformatsky, S., Formation
de l'acide dimethylglutarique ; Daine, Synthese de l'acide phenyloxypivalique ; Andres,
L. .Synthese de l'acide ethylphenyllactique ; Cucnlesco, /., Sur l'acide dimethylisobuty-
llactique ; Zelinsky, D. , Sur le trimethylhexamethylene (pp. 584-602).

Band ccxxxiv. Heft 1. Archiv de Pharmacie. (2nd January, 1896.)

Gadamer,/., Ueber das Thiosinamin II. (pp. 1-48). Boettinger, C, Ueber einige Abkomm-
linge der Sulfometabrombenzoesaure (pp. 48-55). Dragendorff, G. , Beitrage zur gerich-
tlichen Chemie (pp. 55-80). Gadamer, J. , Berichtigung (p. 80).

Band ccxxxiv. Heft 2. (22nd February, 1896.)

Dragendorff, C, Beitrage zur gerichtlichen chemie (pp. 81-87). Boettinger, C., Ueber einige
Abkommlinge des Acetessigathers (pp. 87-91). Boettinger, C, Ueber glyoxylsaures
Natrium (pp. 91-92). Virchow, H., Ueber Bau und Nervatur der Blattzahne und Blatt-
spitzen (pp. 92-154). Luis, G., Ueber die oblito-schizogenen Secretbehalter der Mystaceen
(pp. 154-158). Boettinger, C, Ueber einige Abkommlinge der Glykolsaure (pp. 158-160).

Jahrgang xxix. No. 3. Benchte der Deutschen Chemisclien Gesellschaft.

(24th February, 1S96.)

Fischer, £., Krystallisirte wasserfreie Rhamnose (pp. 324-325). ffsese. O., Notiz ueber die
Wurzel von Rumex napalensis (pp. 325-326). Baeyer. A., Ortsbestimmungen in der
Terpenreihe (pp. 326-329). Eckenroth, H., und Klein, A'., Ueber die Einwirkung einiger
sauerstofthaltiger Halogenverbindungen auf Benzoesauresulfinidnatrium (Saccharin) (pp.
529-333). Zelinsky, N., und Tscke?-noswitow, N. , Ueber stereoisomer Dimethyltricar-
ballylsliuren (pp. 333-340). Clever, A., und Muthmann, W., Untersuchungen ueber den
Schwefelstickstoff (pp. 340-343). Tiemann, F., Bemerkung (pp. 343"344)- Hell< C., und
Gaab, C, Ueber Derivate des Isoanethols (pp. 344-352). Schulse, £., Ueber das
Vorkommen von Arginin in den Knollen und Wurzeln einiger Pflanzen (pp. 352-356).
Sommer, E. A., Ueber a- und /3-Styrolnitrosit (pp. 356-361). Fischer, 0., und Hepp,
£., Nachtriige zur Kenntniss der Induline und Safranine (pp. 361-372). Koenigs, II.,
Ersetzung von Hydroxyl in Chinaalkaloi'den durch Wasserstoff. II. (pp. 372-375). Harries,
C., und Bitsse, G., Ueber Reduction einiger ungesattigter aromatischer Ketone und ihre
Ueberftihrung in Cumaranderivate (pp. 375-380). Harries, C., und Eschenbach, G., Ueber
Reduction ungesattigter Ketone (pp. 380-389). Willstdtter, R., Ueber einige Derivate
der Pipecolinsaure (pp. 389-393). Willstdtter, R., Ueber das Tropinon (pp. 393-403)-
Zelinsky, N., und Rudsky, M., Synthetische Versuche in der Pentamethylenreihe (pp. 403-
405)-

Jahrgang xxix. No. 4. (9th March, 1896.)

Herty, C. H., Ueber gemischte Haloi'de des Platins und Kaliums (pp. 411-414). Jaubert,
G. P., Beitrage zur Nomenclatur der Farbstoffe der Phenazinreihe (pp. 414-418).

ENUMERATION OF TITLES. xix

Beckmann, E., und Eickelberg, H., Zur Kenntniss der Menthone, Ueberfiihrung in
Thymol (pp. 418-421). Ladenburg A., Zur Constitution des Tropins (pp. 421-422).
Ladenburg, A., Ueber das Isopipecolin (pp. 422-424). Krafft, F. , und Lyons, R. E.,
Ueber Diphenylselenon CgH5 . Se02 . CgH5 (pp. 424-428). Krafft, F., und Kaschau, A.,
Ueber die Syn these der aromatischen Selenverbindungen vermittels Chloraluminium
(pp. 428-435). Krafft, F., und Lyons, R. E., Ueber Thianthren (Diphenylendisulfid)
C12H8S2 und Selenanthren. I. (pp. 435"443)- Krafft, F. , und Kaschau, A., Ueber Thianthren
und Selenanthren, C12 H8 S&j. II. (pp. 443"446)- Bamberger, E., Experimentalbeitrage
zur Chemie der Diazoverbindungen (pp. 446-474). Van Erp, H., Ueber die Wirkung
von schmelzendem Kali auf Methylnitramin und Dimethylnitramin (pp. 474-476). Bon-
dzynski, St. von, Ueber das Cholesterin der menschlichen Faeces (pp. 476-478). Eutkyme
und Klinienko, B., Ueber die Reaction der unterchlorigen Saure mit Chlorkobalt und
Chlormangan (pp. 478-481). Ciamician, G., und Silber, P., Ueber die Alhaloi'de der
Granatwurzelrinde (pp. 481-490). Ciamician, G., und Silber, P., Ueber das n- Methyl-
troponin (pp. 490-494). Wislicenus, H. , Glatte Reduction der Nitrogruppe zur Hydroxyl-
amingruppe (pp. 494-496). Pschorr, R., Neue Synthese des Phenanthrens und seiner
Derivate (pp. 496-501). Meyenburg, F. v., Ueber die Einwirkung von Chlorkohlenoxyd
auf Dimethyl- und Diathyl- m- aminophenol (pp. 501-513). Harries, C, und Loth, G.,
Zur Constitution der 1- Phenyl- pyrazolone (pp. 513-521). Harries, C, Ueber die Oxime
der cyclischen Acetonbasen und das p- Aminotrimethylpiperidin (pp. 521-529). Tiemann,
F., und Senimkr, F. IV, Ueber Pinonsaure (pp. 529-544). Jnuger, E., und Klages, A.,
Ueber Halogenderivate des Camphens und Hydrocamphens (pp. 544-547). Lawrence,
IV. T., Ueber Verbindungen der Zucker mit dem Aethylen-, Trimethylen- und Benzyl-
mercaptan (pp. 547-552). Kraemer, G., und Spilker, A., Ueber das Cyclopentadien im
Steinkohlentheer, das Inden der Fettreihe (pp. 552-561).

Band liii. Nos. 2-3. Journal fiir pmktische Chemie. (1st February, 1896.)

Thudichum, J. L. IV, Ueber das Phrenosin, ein unmittelbares Educt aus dem Gehirn und
die Producte seiner Chemolyse mit Salpetersiiure (pp. 49-91). Zincke, T., und Helmert,
B., Zur Constitution der Azimide (pp. 91-100). Zincke, T., Ueber die Umwandlung von
Bromprotocatechusiiure in eine Dibrom- o- Naphto- Chinoncarbonsaure (pp. 100-106).
Claus, A., und Schnell, L., p- Nitrochinolin und p- Amidochinolin (pp. 106-127). Knorr,
L., Erwiderung auf die Abhandlung von R. von Rothenburg: Isomeriefalle in der Pyrazol-
reihe (Herm. L. Knorr zur Antwort) (pp. 127-132). Walter, J., Druckrohr fiir Labora-
toriumsversuche (pp. 132-139). Schall, C, Ueber 7-Carbodiphenylimid (pp. i39-x43)-
Lotlermoser, A., Zur Kenntniss der Einwirkung von Natruim auf aromatische Nitrile IV.
(pp. 143-144).

Band xvi. Heft 10. Monatshefte fiir Chemie und verwandte Thiele andcrer Wis-

senschaften. (31st January, 1896.)

Glucksmann , C, Zur Bildung des Pinakolins aus Calcium iso-butyrat (pp. 897-906). Herzig,
J., Ueber Haematoxylin und Brasilin III. (pp. 906-919). Kostanecki, St. v., und Tambor,
J. , Ueber einen weiteren synthetischen Versuch in der Gentisinreihe (pp. 919-927).

Band xi. Heft 10. Zeitschrift fiir A norganische Chemie. (20th February, 1896.)

Rosenheim, A., Ueber die Einwirkung organischer Metallsauren auf organische Sauren (pp.
225-249). Gooch, F. A., und Peirce, A. W., Jodometrische Bestimmung der selenigen
Saure und der Selensaure (pp. 249-254). Reizenstein, F, Ueber einige Metallsalze mit
organischen Basen II. (pp. 254-264). Flawitzky, F, Ueber eine Funktion, welche der
Periodizitat der Eigenschaften der chemischen Elemente entspricht (pp. 264-268). Alaw-
row, F, und Muthmann, W., Zur quantitativen Bestimmung und Scheidung des Kupfers
(pp. 268-272). Arctowski, H., Untersuchungen ueber die Loslichkeit beim Erstarrung-
spunkte der Losungsmittel (pp. 727-28). Hofmann, K. A., Ueber das Nitroprussid-
natrium (pp. 278-288). Hofmann, K. A., und Wiedc, O. F., Neue Darstellungsmethoden
des Phenylesters der Eisentetranitrososulfosaiire (pp. 288-293).

xx SCIENCE PROGRESS.

Band xix. Heft 2. Zeitschrift fiir Physikalische Chemie. (25th February, 1896.)

Linck, G., Beitragzu den Beziehungen zwischen dem Krystall und seinem chemischen Bestand
(pp. 193-201). Ortloff, W., Beitrag zur Kenntnis eutropischer Reihen (pp. 201-228).
Bredig, G., Ueber Wiirmeleitung und Ionenbewegung (pp. 228-233). Wildermann, M.,
Experimenteller Beweis der van't Hoffschen Konstante, des Arrheniusschen Satzes, des
Ostwaldschen Verdtinnungsgesetzes, des Daltonschen Gesetzes u. s. w. in sehr verdiinnten
Losungen (pp. 233-251). Zanninovich-Tessari?i, H., Elektrolytische Dissociation der
Losungen in Ameisensaure (pp. 251-261). Le Blanc, M., und Rohland, P., Ueber den
Einfluss, welchen die elektrolytische Dissociation, der Wechsel des Aggregatzustandes und
des Losungsmittels auf das Lichtbrechungsvermogen einiger Stoffe Ausiiben (pp. 261-287 ).
Hertlein, H., Beitrage zur Kenntnis der Polythionate (pp. 287-318). Van, Laar, J. J.,
Zur Antwort an Herrn Prof. W. Nernst (pp. 318-323). Rodger, J. W., und Watson, W.,
Ueber die magnetische Drehung der Polarisationsebene des Lichtes in Fliissigkeiten. I.,
Teil : Schwefelkohlenstoff und Wasser (pp. 323-380).

APPENDIX I.

NOTICES OF BOOKS.

The Cambridge Natural History, vol. v., " Peripatus," by Adam Sedgwick ; " Myria-
pods," by F. G. Sinclair; "Insects," by D. Sharp. 8vo, pp. xi. and 584. London:
Macmillan & Co., 1895.

We were told in the prospectus that " The Cambridge Natural History is intended, in the
first instance, for those who have had no special scientific training, and who are not necessarily
acquainted with scientific language". Mr. Sedgwick's chapter on Peripatus in the present
volume gives a very curious interpretation to this intention. This chapter is, to a large extent,
written in language which is nothing if not scientific, and which, however clear and intelligible
to the well-versed student, must, at times, be completely mystifying to the untutored.
Except in a few pages, where in simple words he describes the living Peripatus and its habits
and external features, the style of his writing is much better suited to a scientific monograph
or a text-book of comparative zoology. Here is a sample of it, taken from the section
on development "The segmentation is peculiar, and leads to the formation of a solid
gastrula, composed of a cortex of ectodermal nuclei surrounding a central endodermal mass,
which consists of a much-vacuolated tissue with some irregularly shaped nuclei. The endo-
derm mass is exposed at one point — the blastopore (gastrula mouth). The central vacuoles
of the endoderm now unite and form the enteron of the embryo." The anatomy of Peri
patus is somewhat similarly treated of in another section. These two sections, the most
important in the chapter, will, no doubt, give pleasure to those readers who already possess
some knowledge of the subjects, and to those who do not they may prove an incentive to go
through a course of special training. Some excellent figures are scattered through the chapter,
and there is a map to show the geographical distribution of the genus. A list of species, with
their localities, is appended, and some of the species are briefly characterised. This list, or
synopsis as it is called, may be useful to some readers, but for the systematic student it will
have little value, as Mr. Sedgwick has apparently not taken the trouble to bring it up to date,
and it differs in no essential respect, so far as we can judge, from one which he published with
his monograph several years ago.

Mr. Sinclair tells us in his chapter on the Myriapods that he " only aims at giving an
outline sketch of the group that shall be intelligible to the general reader who has not made a
special study of such matters ". In this aim he has, to some extent, succeeded very well. But
this is not all that we were led to expect. For did not the prospectus also say that "an
attempt would be made, not only to combine popular treatment with the latest results of
scientific research, but to make the volumes useful to those who may be regarded as serious
students of the various subjects"? We do not wish to imply that Mr. Sinclair has not made
such an attempt. Evidence of it is in fact to be found in those parts of the chapter in which
he writes on subjects with which his own researches have been particularly associated, but we
find very few traces of it elsewhere. His general introduction, in which he speaks of the habits
of Myriapods, is good, and his account of the itructure and development of some of the
groups leaves nothing to be desired. But when we turn to his treatment of classification and
his account of some of the smaller but not less interesting orders there is a different tale to tell.
Mr. Sinclair is apparently unaware that the whole subject of the classification of Myriapods
has in recent years been completely revised, and his own attempt at classification is a mere
revival of the antiquated system of Koch, with the addition of the two orders Symphyla and
Pauropoda. Pocock and Kingsley, to mention two only of the chief authorities, will scarcely
feel flattered to find that there is not the slightest reference to their views published several
years ago, and not yet so far as we know disputed, that the so-called Myriapods do not con-
stitute a single homogeneous class but consist of least two very distinct groups. We do not
feel competent to follow Mr. Sinclair through his detailed accounts of the different orders, but
if his treatment of the Symphyla may be taken as a sample of the rest, his performance in this
respect is very poor indeed. Scolopendrella, the sole genus of this order, shows certain points
of resemblance to the Thysanura, and is by some considered to be the living type which comes
nearest to the ancestral forms of both Myriapods and Insects. Mr. Sinclair very properly calls

C

xxn SCIENCE PROGRESS.

attention to the special interest which thus attaches to it, but how does he proceed to satisfy
the desire for more detailed information? He gives no figure of the genus, and as to the
number of species or as to the habits or habitat of any one of them, although two species are,
we believe, common enough in this country, he says not a word. He points out it is true how
Scolopendrella differs from Campodea, but in what respects it exhibits "a great resemblance
to the Thysanura " he forgets to mention. We are told in one place that it has a pair of legs
to each segment of the body, and in another that the smaller segments do not bear legs. The
caudal appendages are described as hook-like, but why they should appear so to Mr. Sinclair
and not to others we need not stop to inquire. The genital opening of Scolopendrella, he tells
us, is on the last segment of the body, though he gives no reason for refusing to accept the
statements of Ryder, Grassi, Haase and others, who tell us on the contrary that this opening
is on the fourth segment. There is of course no reference to the remarkable coxal spurs and
saccules of Scolopendrella ; such matters being perhaps considered outside the interest of the
.general reader. As the volume is mainly entomological and intended as well for serious stu-
dents, a fuller treatment of these structures would not we think be altogether out of place. In
other parts of the chapter we notice a few inaccuracies which might with ordinary care have
been avoided. Thus we read on p. 59 that " the generative system of Chilopoda differs chiedy
in the opening of the genital apparatus at the end of the body instead of in the third segment ;
though this difference only separates the order from the Chilognatha and not from the other
•orders". The natural inference from this statement is that in all the other orders the genital
opening is at the end of the body, but this is true only of the Schizotarsia. Again on p. 43 it
is stated that the genital organs of the Chilognatha open on " one of the anterior rings of the
posterior part of the body, usually the seventh ". Bat this palpable slip is corrected in another
place. Mr. Sinclair's references to Cuvier on page 77 we must also attribute to carelessness,
for he could scarcely be so ill acquainted with the history of his subject as not to know that it
was Latreille and not the great anatomist " who united the Myriopods with the Insects, making
them the first order and the Thysanura the second," and who was thus the first to "claim a
close relationship" between the two groups.

Dr. Sharp's Chapters on the Insects fill more than 500 of the whole 584 pages in the
volume. They cover only a part of his subject, which is to be continued in another volume
entirely devoted to the purpose. When we consider the vast extent of entomological literature
and the number and variety of workers who have been engaged on this branch of science, it
must be admitted that to write such an account of Insects as shall embrace all the most
valuable and most generally interesting facts and shall at the same time be free from serious
errors is by no means an easy task, and requires the exercise of considerable knowledge and
judgment. The success with which Dr. Sharp has so far accomplished this task is not
surprising to those who know him, but is not the less a matter for congratulation to himself as
well as to his readers. His work is in most respects brought well up to date, and puts the
reader in touch with nearly all the latest researches in every branch of Entomology, while for
the student who wishes to follow up any particular subject copious references to original
memoirs are supplied. Dr. Sharp is generally very guarded, almost too guarded in his state-
ments, appearing throughout as the impartial recorder rather than as the exponent of any
particular views, and seldom giving expression to his own opinion even on matters on which it
might be expected to carry much weight. He refers for example without any comment to the
suggestion that the elytra of beetles are homologous with the tegulne and not with the anterior
wings of other insects, though we have good reason to know that he himself holds the opposite
view. Occasionally, however, he betrays some indication of his leanings. Thus on the subject
of insect-vision he seems to hold with those who believe that insects perceive only " the lights,
shades, and movements of the external world," and can distinguish neither form nor colour.
He does not state this explicitly, but such is the inference we draw from the few remarks he
makes on this interesting subject. We notice too that in describing the structure of the com-
pound eye he omits all reference to the view long ago expressed by Straus-Durckheim and
recently revived by Van Patten, that the crystalline cones are really percipient and not merely
dioptric elements of the eye. Dr. Sharp's writing is generally very clear, but there are one or
two places in which he leaves us in some doubt as to the drift of his remarks. From what he
says on p. 89 he seems to admit the probability that in different insects the head is composed
of a different number of primary segments, from three to six or even possibly seven, and that the
"thorax" also may in some insects be composed of six and in others of three primary segments.
Again in a footnote on p. 91, he speaks of the wings as " appendages " which " differ but little in
their nature from legs ". If he really holds the remarkable views which seem to be implied by his
words in both these cases, we should like him to have stated them a little more clearly. One

NOTICES OF BOOKS. xxm

or two other points in his account of the structure of insects call for some slight notice.
" Comparison," he says, " suggests that the hypoglottis of Coleoptera may possibly represent
the piece corresponding to the mentum of Orthopterists, the so-called mentum of beetles being
in that case the sub-mentum of Orthopterists ". This suggestion agrees very well with the
statements appearing in so many text-books of comparative anatomy, in which the sub-mentum
of Orthoptera is treated as part of the lower lip, and it seems to be supported by the figure
which Dr. Sharp gives of the mouth parts of Locusta. But this figure is we fancy not
altogether accurate. Comparison really seems to show that entomologists generally are right
in regarding the sub-mentum of Orthoptera as part of the head, and homologous with the
sub-mentum of beetles. This at least is the view which Waterhouse has taken • after
instituting a series of very careful comparisons. Entomologists, however, are not always con-
sistent in their use of anatomical terms, and we fancy we see an illustration of the fact in Dr.
Sharp's use of the term clypeus. For what he figures and describes as the clypeus in the case of
the cricket's head, does not seem to correspond with that part of the head of the cockroach which
he denotes by the same name. This is, however, a minor point, and in a writer of less general
accuracy than Dr. Sharp would probably escape notice altogether. There are a few omissions
which had they been supplied would have added to the value of some of the chapters. In his
general account of the embryonic development of insects, he says nothing about the post-oral
origin of the antennae or of the appearance of leg-rudiments on the abdomen. His account of
the Thysanura, remarkably full in other respects, is deficient in information about the interest-
ing character of the mouth-parts, which is all the more to be regretted as it has so much bearing
on the suggestion, to which in another place he refers, that the hypopharynx or rather the lobes
at its base represent an additional pair of mouth-appendages. The least satisfactory part of
Dr. Sharp's work is perhaps that in which he deals with the general classification of insects.
Here he discusses the different systems proposed, and shows what every one is ready to admit
that none of them is perfect, while at the same time he endeavours to excuse himself for revert-
ing to one of the oldest and least natural of all. With his treatment of the different orders,
which in this volume include the Aptera, Orthoptera, Neuroptera and a portion of the Hymenop-
tera we have no fault to find. Hi really seems to discount his own views on classification by
the care with which he points out the close affinities between many of the groups of Pseudo-
neuroptera and the true Orthoptera. The work is excellently illustrated, and besides being full
of interest for the general reader will prove extremely useful to the student. It promises to be
when completed the best modern text-book of Entomology in the English language.

Grundzuge der Marinen Ticrgeographie ; Anleitung zur Untersuchung der geograpkischen
Verbreitung Mariner Tiere, mlt besonderer Beriicksicktigung der Dekapodenkrebse.
Von Dr. Arnold E. Ortmann in Princeton, N.J., U.S.A. Mit i Karte. Jena, 1896.
96 pp.

Dr. Arnold Ortmann's clever essay is principally concerned with the distribution of marine
animals, objects with which his own studies have made him especially familiar. But he here
only uses them to illustrate the general principles which he desires to commend to the student
of distribution.

In a useful historical summary he sets forth the successive attempts that have been made
to explain or to describe the real or supposed distribution of animals now living on the globe.
At the outset it was not unnatural to fancy that the range of animal groups would bs deter-
mined by the zones of temperature. A striking personality like the polar bear for instance is
not met with in the tropics, nor are there any arctic or antarctic monkeys, and in the ocean
reef-corals will not support a temperature below 66° F. For the division of the zones into
regions and subregions, various zoologists selected the range of some particular species or
group with which they happened themselves to be best acquainted. But the typical species
sometimes turns out to represent nothing but itself, and in the mapping out of provinces and
districts there is no security that the boundaries will apply to any animals but those on which
they were empirically based. To Andrew Murray is awarded the commendation that as early
as 1866 he "inquires into causes for the existing condition of things, and finds them in the
geological development of the earth, in the changing distribution of land and water, and at the
same time lays stress on the importance of barriers and the limits of range ". Thus was he an
important forerunner of Wallace, who first effectively established the fundamental principles
that the distribution of life is dependent on the geological history of the earth's surface, on

1 The Labium and Sub-mentum in certain Mandibulate Insects, by C. 0. Waterhouse.

xxiv SCIENCE PROGRESS.

limits of range, on means of dispersal, and that the two latter influences are different for
different animals.

Dr. Ortmann considers that the pecularities in the conditions of existence which affect
animal life may conveniently be grouped under three headings, as those which have to do with
light, medium and substratum. Without light there is no vegetation. Without vegetation
there is no food which animals can assimilate. According to the medium in which they live
they must be fitted for air-breathing or water-breathing. The substratum may be dry land or
ocean floor, but those animals which are dependent upon either must have the locomotive
apparatus by which they obtain their food adapted accordingly. From these considerations
Dr. Ortmann divides the globe into five principal life-areas. The medium distinguishes the
land-area, of which the occupants are air-breathers, from all the rest. The abyssal area is set
apart from all by the absence of light. The pelagic area stands alone in having occupants
independent of any solid resting-place. The fluvial or fresh water area carries its characteristic
in its name, and there remains the littoral area, not so sharply marked off as the others, but
perhaps the most important of all, if from its teeming bosom the thronging forms of life have
felt and found thei.r way into all the other areas, spreading over the high seas, colonising the
profoundest abysses, threading their course up estuaries and rivers, climbing the terraces of
the land and taking wing beyond the clouds.

By paying regard to climatic and topographical relations, Dr. Ortmann finds himself able
to subdivide the littoral and the pelagic areas into regions and subregions. In each there is
an Arctic, an Antarctic, and an Indo-pacific region. In the pelagic area there is also an
Atlantic region, while in the littoral there are three additional regions, a West-American, an
East-American, and a West-African. In the last a Mediterranean subregion is distinguished
from a Guinea subregion, and there are similar and further subdivisions suggested in some of
the other areas. Only the abyssal area is spoken of as "without differentiation into regions
and subregions ". As distinguished from the Continental, Freshwater, and Littoral areas, the
author maintains that " in the Abyssal and Pelagic areas the continuity is complete, in no part
of the earth are special portions of these two topographically separated from others, but every-
where they stand in direct communication ". This mode of viewing the abyssal area seems to
be of very doubtful validity. There are submarine mountains, submarine lakes, warm currents
and cold currents functioning as submarine rivers, which must operate as climatic and topo-
graphical barriers as forcibly in the unlighted marine abysses as they do in the realms of day-
light. Considering, too, the intimate dependence of animal life upon the available food, it
would be strange indeed if no regions and subregions were marked by the varying character
of the ocean floor, with its diatom ooze and radiolarian ooze and globigerina ooze, and other
distinctive coatings. Were the deep sea in fact an uninterrupted uniform expanse, it might be
expected, and at one time was expected, to have a fauna common to the whole of it. But of
this there is at least no striking evidence, and Dr. John Murray of The Challettgc}- adduces
some evidence which is rather striking in the contrary direction. Thus at a station in mid-
equatorial Atlantic, in 1850 fathoms, 38 species were obtained. At a station in mid-equatorial
Pacific, in 2425 fathoms, 29 species were obtained. Both were on globigerina ooze. Only one
species was common to the two localities, and that one the little Disciua Atlantica, belonging
to a genus which ranges from the Cambrian to the present time.

In the vast area of the subject there are many regions and subregions of discussion into
which this short notice cannot follow Dr. Ortmann. All that he has to say, whether it com-
mands assent or otherwise, will be found worthy of attention. He brings very clearly into view
the merits and occasionally the demerits of his predecessors. He shows how much we have
still to learn, what points of vantage have been attained, in what direction the line of advance
should be followed with most hope of success. The zoologist can scarcely peruse this memoir
without finding that his own scientific studies from one side or another are closely connected
with the complex problem of the distribution of animals.

APPENDIX II.

CHEMICAL LITERATURE FOR MARCH, 1896.

Vol. i. No. 4. American Journal a/ Science. (April, 1896.)
Wolff, J. E., Occurrence of Theralite in Costa Rica, Central America (pp. 271-273).
Merrill, G. P. , Occurrence of Free Gold in Granite (pp. 309-312).

Vol. xviii. No. 4. Journal of the American Chemical Society. (April, 1896.)

Morekead, J. T., and De Chalmot, G., The Manufacture of Calcium Carbide (pp. 311-331).
Gomberg, M. On the Action of Wagner's Reagent upon Caffeine and a New Method for
the Estimation of Caffeine (pp. 331-342). Long, J. H. , On the Formation of Antimony
Cinnabar (pp. 342-347). Gomberg, /I/., Perhalides of Caffeine (pp. 347-378). Wiley, H.
IV., Determination of the Heat of Bromination in Oils (pp. 378-385). Mixer, C. T., and
Dii Bols, H. W., Siirnstroms Method of Determining Manganese in Iron Ores (pp. 385-
389). Veiteh, F. P., On the Various Modifications of the Pemberton Volumetric
Method for Determining Phosphoric Acid in Commercial Fertilisers (pp. 389-397).
Bigelow, W. D., Index to the Literature on the Detection and Estimation of Fusel Oil in
Spirits (pp. 397-402). Walt, C. E., The Occurrence of Titanium (pp. 402-404). Cone,
E. F., The Estimation of Pyrrholite in Pyrites Ores (pp. 404-406). Auchy, G., Drown's
Method of Determining Sulphur in Pig Iron (pp. 406-412).

Vol. xviii. No. 3. American Chemical Journal. (March, 1896.)

Orndorff, W. R,, and Terrasse, G. L., The Molecular Weight of Sulphur (pp. 173-207).
Mabery, C. F., On the Determination of Sulphur in Illuminating Gas and in Coal
(pp. 207-215). Mabery, C. F., and Dunn, O. C, Chemistry of the Berea Grit Petroleum
(pp. 215-236). Morse, H. N., and Chambers, A. D., A Method for the Standardisation
of Potassium Permanganate and Sulphuric Acid (pp. 236-238). Jackson, C. L., and
Galllvan, F. B., Some Derivatives of Unsymmetrical Tribrombenzol (pp. 238-252).

Vol. xxi. No. 241. The Analyst. (April, 1896.)

Allen, A. H., Note on the Titration of Quinine (pp. 85-87). Allen, A. H., Note on the
Preparation of Pure Hydrochloric Acid (pp. 87-88). Richmond, H. D., The Composition
of Milk and Milk Products (pp. 88-92). Richmond, H. D., and Boseley, L. A'., Further
Notes on the Detection of Formalin (pp. 92-94). Hehner, O., The Detection of For-
malin (pp. 94-99). Shepherd, H. H. B., Official Methods for the Analysis of Fertilisers,
issued by the German Manure Manufacturers' Association (pp. 99-102).

Vol. lxix. No. 401. Journal of the Chemical Society. (April, 1896.)

Humphreys, W. J., Solution and Diffusion of certain Metals in Mercury (pp. 243-253). Bone
W. A., and Perkln, W. H., Jun., The Symmetrical Dimethylsuccinic Acids (pp. 253-
268). Bone, W. A., and Perkin, W. H., Jun., Note on the aa-Dimethylglutaric Acids
(pp. 268-270). Bent ley. If. H., Perkin, W. H., Jun., and Thorpe, J. F., Cls- and trans-
Methylisopropylsuccinic Acid (pp. 270-287). Wood, T. B., Available Potash and Phos-
phoric Acids in Soils (pp. 287-292).

Vol. xv. No. 3. Journal of the Society of Chemical Industry. (31st March, 1896.)

Schack-Sommer, G., Sorghum Sugar Manufacture in Spain (p. 155). Sautter, E. H., The
Analysis of Chrome Ore and Ferro-Chromium (pp. 155-158). Grossmann, J., Recent
Developments in the Manufacture of Chlorates (pp. 158-161I Macadam, S., On De-
structors for Consuming Town Refuse — their Requirements, Defects, and Modes of
Improvement (pp. 162-169). Clowes, F., The Estimation of Oxygen by Alkaline Solution
of Pyrogallol (p. 170). Caven, R. M., Some Properties of Ferric Phosphate (Discussion)
(pp. 170-171). Richardson, F. II'., and Aykroyd H. £., Sulphides, Sulphites, Thiosul-

xxvi SCIENCE PROGRESS.

phates, and Sulphates — their Estimation in Presence of Each Other (pp. 171-173).
Steaurt, D. R., The Standard of Minimum Flash-Point for Mineral Oil (pp. i73"I79)-
Thompson, C. W., Method of Analysis of Alloys of Lead, Tin, Antimony and Copper
(pp. 179-182). Warwick, A. W., Laboratory Testing in connection with Gold Extrac-
tion (pp. 182-184).

Vol.41. No. 251. Philosophical Magazine and Journal of Science. (April, 1896.)

Arrhenius S., On the Influence of Carbonic Acid in the Air upon the Temperature of the
Ground (pp. 237-276). Witkowski, A. W., Thermodynamic Properties of Air (pp.
288-315). Ramsay, W., and Eumorfopoulos, N., On the Determination of High Tem-
peratures with the Meldometer (360-367). Wood, R. IV., A Duplex Mercurial Air-pump
(pp. 378-381).

Vol. lix. No. 355. Proceedings of the Royal Society. (30th March, 1896.)
Lord Raleigh, On some Physical Properties of Argon and Helium (pp. 198-208). Tilden, W.
A., An Attempt to Determine the Condition in which Helium and the Associated Gases
exist in Minerals (218-224). Schunck, E., and Marchlewski, L., Contributions to the
Chemistry of Chlorophyll VII., Phylloporphyrin and Haematoporphyrin — a Comparison
(pp. 233-236). Dunstan, II". R., and Boole, L. £., An Enquiry into the Nature of the
Vesicating Constituent of Croton Oil (pp. 237-249).

Tome vii. Annals de Chemie et de Physique. (April, 1896.)

Malbot, H. et A., Recherches sur les phosphats d'Algerie. Cas d'un roche presentant la
composition d'un superphosphate (pp. 433-520). Moissan, H., et Gautier H., Deter-
mination de la chaleur sp£cifique du bore (pp. 495-573).

Tomes xv.-xvi. No. 6. Bulletin de la Societe Chimique de Paris. (20th March,

1896.)
Tassilly, Oxyiodures de Zinc (pp. 345-347). Urbain, G., Contribution a l'e'tude du thorium

(pp. 347-349). Tanret, C, Sur les modifications moieculaires et la multirotation des

sucres (pp. 349-361). Secreiant, Ethers phosphoriques des phenols polyatomiques (pp.

361-364). Reychler, A., Sur le chlorure de geYanyle (pp. 364-366). Reychler, A., E'tudes

sur les terpenes (pp. 366-376).

Tome xv.-xvi. No. 7. (5th April, 1896.)
Camot, A., Analyse, par les process volumdtriques, d'un melange de chlorures, d'hypochlorites
et de chlorates (pp. 393-397). Camot, A., Analyse d'un melange de chlorures, de chlorates
et de perchlorates (pp. 397-399)- Varct, R., Loi des doubles decompositions entre le
cyanure de mercure et les sels des melaux alcalins et alcalind-terreux (pp. 399-400).
Foumier, H., Sur les carbures diethyieniques (pp. 400-404). Bietrix, A., Action de la
nitroso-dimethytaniline sur quelques derives bromes de l'acide gallique (pp. 404-409).
Genvresse, P. , Contribution a l'etude des disulfures aromatiques (pp. 409-426). B'echamp,
A., Sur les alterations spontanea du lait et sur celles que la cuisson lui fait subir (pp.
426-455). Urbain, G., Sur la reaction de Schiff (pp. 455-456). Violette, C, Azurage des
farines par le bleu d'aniline. Comment on peut le reconnaitre (p. 456).

Tome cxxii. No. 10. Comptes Rendus hebdomadaires de V Academic des Sciences.

(9th March, 1896.)

Gautier, A., et Holier, //., Sur quelques conditions qui reglent les combinaisons gazeuses.
Union de l'oxygene a l'hydrogene aux basses temperatures (pp. 566-573). Moissan, H.,
et Etard, Sur les carbures d'yttrium et de thorium (pp. 573-578). Thomas, V., Action du
peroxyde d'azote et de l'air sur le chlorure de bismuth (pp. 611-613). Coquillion, /., Sur
les modifications apportees au grisoumetre et sur la limite d'approximation qu'il peut
donner (pp. 613-615). Schloesing, T, et Richard, J., Recherches de l'argon dans les
gaz de la vessie natatoire des Poissons et des Physalies (pp. 615-617). Rivals, P., Etude
thermochimique des amides et des sels ammoniacaux de quelques acides chlores (pp. 617-
619). Scheurcr-Kestner, Sur la determination de l'acidite des produits pyroligneux (pp.
619-621). Ferrand, Sur une nouvelle sine de sulfophosphures : les thiophosphates (pp.
621-622). Combes, C, Sur quelques derives du triphenylsilicoprotane (pp. 622-624).
Bouchardat, G., et Tardy, Sur l'essence d'anis de Russie (pp. 624-626).

ENUMERATION OF TITLES. xxvn

Tome cxxii. No. n. (16th March, 1896.)

Moissan et Lengfeld, Sur un nouveau carbure de zirconium (pp. 651-654). Ponsot, A.,
Recherches cryoscopiques (pp. 668-670). Charpy, G., Sur la structure et la constitution
des alliages de cuivre et de zinc (pp. 670-672). Appert, L., Sur le role de l'alumine dans
la composition des verres (pp. 672-673). Barbier, P., et Boicveault, I. , Constitution du
rhodinol (pp. 673-675).

Tome cxxii. No. 12. (23rd March, 1896.)

Becquerel, H., Sur les radiations invisibles emises par les sels d'uranium (pp. 689-694).
Sckuttseriberger &\ Boudouard, Recherches sur les terres contenues dans les sables monazit^s
(pp. 697-699). Schloesing, T., Sur les quantity d'acide nitrique contenues dans les eaux
de la Seine et de ses principaux affluents (pp. 699-703). Demarcay, E., Sur un nouvel
element contenu dans les terres rares voisines du samarium (pp. 728-730). Brizard, L.,
Action des reducteurs sur les composes du ruthenium nitrose (pp. 730-733). Fer'ee, J.,
Sur les amalgames de molybdene et quelques propritites du molybdene m^tallique (pp.
733). Barillot, E., Sur les produits de la distillation du bois (experiences industrielles)
(pp. 733-736). De Coninck, O., Sur l'isomerie dans la serie aromatique (pp. 736-737).
Barbier, P., et Bouveault, L. , Sur le rhodinal et sa transformation en menthone (pp.
737-739)-

Tome cxxii. No. 13. (30th March, 1896.)

Becquerel, H., Sur les proprieles differentes des radiations invisibles Emises par les sels
d'uranium, et du rayonnement de la paroi anticathodique' d'un tube de Crookes (pp.
762-767). Moureu, C, Safrol et isosafrol. Synthese de l'isosafrol (pp. 792-795).
Barbier, P., et Bouveault, L., Sur le citronnellal et son isom£rie avec le rhodinal (pp.

795-796)-

Tome cxxii. No. 14. (7th April, 1896.)

Tassi/ly, Etude thermique de quelques oxybromures (pp. 812-814). Besson, A., Action des
acides bromhydrique et iodhydrique sur le chlorure de phosphoryle (pp. 814-817).

i6e Annee. Tome iii. No. 6. Journal de Phavmacie et de Chimie.

(15th March, 1896.)

Prunier, L., Note sur la preparation du sulfoantiomoniate de sodium (sel de Schlippe) (pp.
289-290). Marichal. Le, Note sur la conservation des outils en acier (pp. (290-292).
Balland, Sur la composition des riz imported en France (pp. 292-295).

i6e Annee. Tome iii. No. 7. (1st April, 1896.)

Prunier, L., Essai des iodures officinaux (pp. 337-341). Lagiie, P., Sur l'essai du kermes
(pp. 341-343). La/ay, L. , Contribution a l'etude des liquides ascitiques ; ascite d'origine
tuberculeuse (pp. 343-346). Gorges, Sur une cause d'erreur dans la recherche et le dosage
de l'acide borique (pp. 346-347).

Tome xxviii. No. 1. Journal de la Societe Physico-CJiimique Russe.

Bogorodsky, A., Sur les cryohydrates (pp. 1-10). Chaternikoff, M., et Setchenoff, J., Appareil
pour analyse des gaz (pp. 10-17). Tichvinsky, M., Sur les relations des safranines et des
indulines (pp. 17-24). Reformatsky, S., Action du zinc et de Tether bromoisobutyrique
sur l'aldehyde isobutyrique (pp. 24-40). Barilowitsch, A., Sur l'acide diisopropyloxalique
(pp. 40-47). Ostropiatof, P., Action de la potasse sur l'acetonechloroforme (pp. 47-56).
Wagner. G., Sur la structure des terpenes et composes congeneres (pp. 56-109).
Markownikoff, W., La source de Narsane ; Menschutkin, N., Sur les sels des amides;
Saposchnicoff, A., Sur les propriet^s des solutions aqueuses de l'ac£tone ; Melikoff, P., Sur
le meteorite de Zmen ; Wagner, G., Sur le dosage de l'agrostemme dans la farine ;
Speransky, A., Sur le rhodanure de chrome ; Melikoff, P., Sur les conditions de la for-
mation de la soude naturelle (pp. 109-116).

Band ccxc. Heft 3. Justus Liebig's Annalen der Chemie. (7th March, 1896.)

Kehrtnann, F., Ueber die Beziehungen der Induline zu Safraninen (pp. 247-306). Seliunck,

£., und Marchlexvski, L., Zur Chemie des Chlorophylls. IV. (pp. 306-314). Hesse, 0.r

xxvm SCIENCE PROGRESS.

Zur Geschichte des Proteacins (pp. 314-317). Hesse, O., Ueber den Zuckerbusch (pp.
317-321). Zincke, T., Ueber die Einwirkung von Chlor auf Oxychinoline (p. 321).
Zincke, T., und Winzheimer, E., Ueber Chloroxy-a-chinolin-chinon und dessen
Umwandlungsproducte Hydrinden-, Inden- und Acetophenonderivate der Pyridenreihe,
(pp. 321-359). Zincke, T., und Wicderhold, K., Ueber Dichlor- /8-chinolinchinon und
dessen Unnvandlungsproducte (pp. 359-382).

Band ccxxxiv. Heft 3. Archiv der Pharmacic. (24th March, 1896.)

Piutti, A., Einwirkung der Bernsteinsiiure auf p- Amidophenol und dessen Aether (Pyranlin)
(pp. 161-170). Bottinger, C, Ueber Abkbmmlinge der Naphthylamine (pp. 170-195).
Hesse, O., Ueber die Priifung des Chininsulfats (pp. 195-204). Peinemann, K., Beitrage
zur pharmacognostischen und chemischen Kenntnis der Cubeben und der als Verfalschung
derselten beobachteten Piperaceenfriichte (pp. 204-240).

Jahrgang xxix. No. 5. Bcrichte der Deutschen Chemischen Gesellschaft.

(23rd March, 1896.)

Bamberger, £., Zur Kenntniss normaler Diazometallsalze (pp. 564-577). Veley, I'. H., Die
Reactionsunfahigkeit alkalischer Erden gegen Chlorwasserstoffgas (pp. 577-581). Fischer,
£., und Bromberg, O., Ueber eine neue Pentonsaure und Pentose (pp. 581-586). Richter,
M. M., Ein Beitrag zur Nomenclatur (pp. 586-608). Bamberger, E., Notiz, betreffend
die Ionenzahl der diazosulfonsauren Salze (pp. 608-610). Scholtz, M., Zur Kenntniss der
Semicarbazone (pp. 610-613). Scholtz, M., Ueber einige Derivate des Zimmtaldehyds
(pp. 613-615). Staedel, IV., Synthese des Diphenylketons und seiner Derivate (pp. 615-
616). Zelinsky, N., Zur Kenntniss der stereoisomeren Dimethyltricarballylsauren (pp.
616-618). Darmstaedter, L. , und Liffschutz, J., Beitrage zur Kenntniss der Zusammen-
setzung des Wollfetts (pp. 618-622). Rupe, H., und Heberlein, G., Ueber unsymmetrische
o-Phenylhydrazinderivate (pp. 622-623). Pinnow, /., und Samann, C, Ueber Derivate
des o- Amido-benzonitrils (pp. 623-633). Reissert, A., Ueber die Einwirkung von o- und
p- Nitrobenzylchlorid auf Natriummalonsaureester und einige analoge Verbindungen (pp.
633-639). Reissert, A., Umwandlungen des o- Nitrobenzylmalonsaureesters I. Alkalische
Verseifung, Synthese neuer Indolabkommlinge (pp. 639-665). Reissert, A. , Umwandlungen
des o- Nitrobenzylmalonsaureesters II. Reduction, Bildung von Chinolinderivaten (pp.
665-667). Traube, W. , Ueber einen neuen Weg zur Gewinnung aliphatischer Diazover-
bindungen (pp. 667-670). Ti-aube, W., und Longiuescu, G. G., Ueber Hydrazinosauren
(pp. 670-676). Hell, C, und Portmann, B., Ueber die Einwirkung des Natriumathylats
auf Aethylisoeugenoldibromid (pp. 676-682). Hell, C, und Hollenberg, A., Ueber die
Einwirkung von Natriumathylat auf Anetholdibromid und Monobromanetholdibromid (pp.
682-691). Tiemann, P., und Schmidt, R., Ueber Homolinalool (pp. 691-695). Reychler,
A., Ueber die Einwirkung von Trichloressigsaure auf Terpene (pp. 695-697). Reychler,
A., Ueben Isobornylchlorid und Camphenchlorhydrat (pp. 697-699). Hantzsch, A., und
Schultze, W., Ueber Isomerie beim Phenylnitromethan (pp. 699-703). Kmieppel, C. A.,
Ueber eine Verbesserung des Skraupschen Verfahrens zur Darstellung von Chinolin und
Chinolinderivaten (pp. 703-710), Michaelis, A. , und Luxembourg, K. , Ueber anorganische
Derivate der secundiiren aliphatischen Amine (pp. 710-716). Michaelis, A. , und Silberstein,
E., Ueber Oxyphosphazoverbindungen (pp. 716-729). Zelinsky, N., und Generosow, A.,
Untersuchungen in der Hexamethylenreihe IV. Abhandlung Synthese von Heptanaphten
(pp. 729-734). Klinger, H., und Lonties, C, Ueber die Einwirkung von Schwefelsaure
auf Benzilsaure (pp. 734-742). Wislicenus, II"., Ueber das Verhalten alkalischer Losungen
des Formylphenylessigesters gegen Sauren (pp. 742-743). Gerilowski, D., und Hantzsch,
A., Weiteres ueber die stereoisomeren Salze aus Diazosulfanilsaure (pp. 743-756).

Jahrgang 29. No. 6, (13th April, 1896.)

Ctirtius, T., Ueber Hydrazin, Stickstoffwasserstoff und die Diazoverbindungen der Fettreihe
(pp. 759-784). Hinsberg, O., und Pollak, J., Ueber einige Abkommlinge des Dichlor-
chinoxalins (pp. 784-788.) Coste, J. H., und Parry, E. /., Ueber die Nitirung von
Brombenzol (pp. 788-793). Fischer, £., Ueber das Azophenylathyl und das Acetaklehyd-
phenylhydrazon (pp. 793-798). Paul, C, Ueber oo'-Diphenylpyridin-und-piperidin (pp.
798-801). Konek von Norwall, F., Ueber Hydroderivate von Chinaalkaloi'den (pp. 801-
806). Behrend, O., Constitutionsbeziehungen zwischen Ricinblsaure und Oelsaure-
derivaten (pp. 806-810). Spieckermann , A., Ueber die Constitution der Behenoxyl- und

ENUMERATION OF TITLES. xxix

Stearoxylsaure (pp. 810-813). Goldstein, J. , Ueber das Verhahen von aromatischen
Basen gegen Benzal- und Furfuralmalonsaureester (pp. 813-819). Zelinsky, N., und
Isajcw, W., Ueber Stereoisomere Dimethyldioxyadipinsauren (pp. 819-821). KUster, W.,
Beitriige zur Kenntniss des Haniatins (pp. 821-824). Graebe, C, und Ullmann, F.,
Ueber eine neue Darstellungsweise des o-Oxybenzophenons (pp. 824-826). Graebe, C,
Ueber Synthese des Chrysoketons (Naphtofluorenon) und Constitution des Chrysens (pp.
826-829). Rnpe, H., Ueber unsymmetrische a-Phenylhydrazinverbindungen (pp. 829-
830). Meyer, V., Neue Untersuchungen ueber die Gesetze der Oxim-, Hydrazon- und
Esterbildung (pp. 830-839). Loon, J. van, und Meyer, V., Das Fluorund die Esterregel
(pp. 839-846). Meyer, V., und Sohn, C, Ueber eine eigenthiimliche Bildungsweise der
trimethylirten Mandelsiiure (p. 846). Meyer. V., Ueber die Darstellung einfach und
zweifach acetylirter aromatischer Kohlenwasserstoffe (pp. 846-848). Meyer, V., Ueber
die Salzbildung des Trinitrobenzols (pp. 848-850). Meyer, V., Ueber die Schmelzbarkeit
des Platins im Kohlen-Geblaseofen (pp. 850-852). Freund, .1/., und Siederhofheim, R.,
Beitrag zur Kenntniss des Pseudaconitins (pp. 852-859). Freund, .1/., und Heilbrun, A'.,
L., Ueber die Einwirkung von Salzsaure auf Hydrazo-di-carbonthioallylamid (pp. 859-
863). Bamberger, £., und Knecht, M., Ueber die Reduction der Nitro- zur Hydroxyl-
amingruppe (pp. 863-865). Dierbach, R., Ein neuer Bunsenbrenner (pp. 865-866).
Stoermer, R., und Pogge, W., Ueber disubstituirte Amidoacetone (pp. 866-875).
Gnehm, R., und Banziger, E. , Ueber die bei der Chlorirung von Benzaldehyd auffretenden
Producte und einige Derivate derselben (pp. 875-878). F1 iedlander, P., und Rildf, H.,
Die Darstellung von Flavonderivaten (pp. 878-881). Wagner, G., und Ertschikowsky ,
G., Zur Oxydation des Pinens (pp. 881-886). Wagner, G., und Ginsberg, A., Zur
Constitution des Pinens (pp. 886-890). Tiemann, F., Bemerkungen zur Pinenfrage
(pp. 890-892). Ritthausen, H., Wassergehalt und reaction des Alloxantins (pp. 892-894).
Ritthausen, H., Ueber Alloxantin als Spaltungs product des Convicins aus Saubohnen
(Vicia Faber minor) und Wicken (Vicia sativa) (pp. 894-896). Ritthausen, H., Ueber
Galactit aus den Samen der gelben Lupine (pp. 896-900). Reychler, A. , Ueber Camphen-
bromid (pp. 900-901). Tiemann, F. , und Kriiger, P. , Ueber ein Verfahren zur Reinigung
von Alkoholen (pp. 901-903). Tiemann, F., und Schmidt, R., Ueber die Verbindungen
der Citronnellalreihe (pp. 903-926). Tiemann, F., und Kriiger, P., Ueber zwei sauerstoff-
haltige Basen aus Citronellaldoxim (pp. 926-928). Mahla, F., und Tiemann, F., Ueber
Terpenylsaure (pp. 928-936). Willstalter, R., Ueber ^- Tropin (pp. 936-947). Hantzsch,
A., und Hirsch, B., Ueber intramolekulare Umlagerungen von Diazoniumrhodaniden
(pp. 947-953). Lucas, A., Vicinales Trimethylbenzol als Begleiter des synthetischen
Mesitylens (pp. 953-958). Hantzsch, A., Zur Synthese und Constitution des Benzols (pp.
958-961). Thiele, J., und Meyer, C, Reduction des Methyl-und Aethyl-nitramins (pp.
961-964). Einhorn, A., und Bull, B. S., Ueber das Ortho- Hexamethylendiamin (pp.
964-966). Bischoff, C. A., Studien ueber Verkettungen III. Umsetzung von Chlores-
sigester mit Natrium- malon- und -acet- essigestern (pp. 966-972). Bischoff, C. A.,
Studien ueber Verkettungen IV. Umsetzungen der Natrium -(Alkyl). Malonsaure-ester
mit a- Bromfettsaure-estern (pp. 972-979). Bischoff, C. A., Studien ueber Verkettungen
V. Umsetzungen der Natrium- (Alkyl). Acetessigester mit a- Brom- fettsaure-estern
(pp. 979-982). Bischoff, C. A. , Studien ueber Verkettungen VI. Theoretische Ergebnisse
der Versuche ueber die Bildung substituirter Aethenyltricarbonsaure- und Acetylsuccinsaure-
ester (pp. 982-989). Henrich, F., Ueber zwei Modificationen des Mononitrosoorcins (pp.
989-994). Petrenko-Kritschenko, P., und Stanischewsky, S., Ueber die Condensation der
Aldehyde mit Acetondicarbonsaure-estern (pp. 994-997), Revet din, P\, Ueber einige
Jodderivate des Anisols und ueber einen Wanderungsfall des Jod-Atoms (pp. 997-1005).
Clasien, L., Ueber die Einwirkung des Orthoameisenathers auf Ketonsiiureather, Ketone
und Aldehyde (pp. 1005-1008). Weinland, R.F., und Rumpf, O., Ueber Sulfoxyarsenate
(pp. 1008-1013). Herzig, /., Ueber das Luteolin (pp. 1013-1015). Romburgh, P. van,
Ueber die Nitrirung vom Dimethyl-p-toluidin (pp. 1015-1016). Ruhemann, S., Einige
Beobachtungen in der Pyrazolonreihre (pp. 1016-1018).

Band liii. Nos. 4-5. Journal fiiv praktische Chemic. (29th February, 1896.)
Ipatiew, IV., Ueber die Einwirkung von Bromwasserstoff auf Kohlenwasserstoffe der Reihe
Cn H2n-2 (pp. 145-169. Blomstrand, C. IV., Ueber die Constitution der aromatischen
Diazokorper und ihrer Isomeren (pp. 169-197). Claus, A., und Hartmann, G., Ortho-
ana, Ortho- para, und Meta- ana- dionitrochinolin (pp. 197-210). Kratz, K., Ueber

xxx SCIENCE PROGRESS.

Derivate des m- nitro- o- Amidobenzamids und m- nitro- o- Amidobenzhydrazids (pp.
210-225). Bertram, /., und Gilde»ieis/er, F., Ueber Geraniol und Rhodinol (pp. 225-
237). Hesse, A., Ueber die vermeintliche Identitat von Reuniol, Rhodinol und Geraniol
(pp. 237-241). Vaubel. II'., Der Benzolkern VI. (pp. 241-246). Herfeldt, G., Zur
Kentniss der Kyanalkine, ins besondire des Kyanbenzylins (pp. 246-250). Briiggemann h
F., Ueber Derivate des Veratrols (pp. 250-255). Liebermann, C, Herrn. Michael zur
Erwiderung (pp. 255-256).

Band xi. Heft 6. Zeitschrift filr Anorganische Chemie. (2nd April, 1896.)

Vanderberghe, A., Ueber die Darstellung von reinem Molybdan (pp. 385-397). Vanderiergke,

A., Einwirkung einiger Gase auf erhitzes Molybdan (pp. 397-404). Loven, J. M.,

Chemisches Gleichgewicht in ammoniakalischen Magnesiumsalzlbsungen (pp. 404-416).

Jorgensen, S. M., Zur Konstitution der Kobalt, Chrom- und Rhodium- basen (pp. 416-

454). Barendrecht, H. P., Dimorphie des Eises (pp. 454-456).

Band xix. Heft 3. Zeitschrift fiiv Physikalische Chemie. (31st March, 1896.)

Biltz, H., Ueber die Bestimmung der Molekulargrosse einiger anorganischer Substanzen (pp.
385-431). Zecchini, F., Beitrag zur Kenntis der organischen Verbindungen des vier-
vvertigen Sauerstoffes (pp. 431-436). Gennari, G., Ueber die Geschwindigkeit der
Verseifung in organischen Losungsmilteln (pp. 436-441). Sa/zer, T., Eine Krystall-
wasser- Theorie (pp. 441-456). Lovku, J. M., Affinitats-grdssen einiger organischen
Sauren (pp. 456-465). Donnan, F. G., Versuche ueber die Beziehung zwischen der
elektrolytischen Dissociation und der Lichtabsorption in Losungen (pp. 465-489). Nordk,
V., und Svlc, O., Ueber die Absorption von Rbntgens Strahlen durch Chemische
Verbindungen (pp. 489-513).

Anno xxvi. Vol. 1. Fascicolo 1. Gazzetta Chimica Itahana.
(15th February, 1896.)
Giustiniani, F., Sopra alcuni costituenti dell'ortica (pp 1-7). Angeli, A., e Rimine, E.v
Sopra il nitrosito dell'isosafrolo (pp. 7-13). Cannizzaro, S., e Andreecci, A., Sulla
costituzione del dimetilnaftol proveniente dalla scomposizione degli acidi santonosi (pp.
I3"35)- Namias, R., Considerazioni fotochimiche e termofotochimiche (pp. 35-52).
Baltitmo, L. , Brevi osservazioni sulla nota dei signori Fr. Mahla e Ferd. Tiemann : Zum
Abbau der Camphersaure (pp. 52-61). Garelli, F., Sopra alcune soluzioni solide formate
da sostanze non isomorfe (pp. 61-88).

APPENDIX I.
NOTICES OF BOOKS.

Lehrbuch der Entwicklungsgeschichte des Menschen und der Wirbelthiere. Von Prof. Dr. O.
Hertwig (Fiinfte theilweise umgearbeitete Aurlage). Jena : Gustav Fischer, 1896.

The fact that this admirable work has entered upon a fifth edition in its ninth year is
sufficient testimony to its success. The plan of the book remains unaltered, but the whole
has been brought up to date. The sections dealing with the Structure of the Chorion, the
Development of the Intermediate Germ Layer in Reptiles and Mammals, and the Genesis of
the Cellular Elements of the Blood, are conspicuous among those which have received
attention, and the recent work of Keibel, Will, von Kupffer, Kundrat and Engelmann,
Leopold, Minot, and others, has been largely laid under obligation. This fifth edition is,
however, most noteworthy for the fuller treatment of cytological topics, there having been
added sections dealing with the role of the Centrosome in Fertilisation and the Reduction
Division, and a short chapter of eight pages upon the " Mosaic Theory " of Roux and recent
experimental work which bears upon it. Twenty-two illustrations have been added ; but,
seeing how great has been the success of this work, we had wished for the replacement in late
editions of the hundred and one well-worn illustrations which nauseate us by their reappear-
ance in text-book after text-book. Rathke's time-honoured diagrams of the development of
the aortic arches are once more reproduced in full, but the work of Boas, Hochstetter, and
Zimmermann, upon the pre-pulmonary arch, which has undermined them, is mentioned only
in small type. This is but one of several instances in which recent work of a far-reaching
order is insufficiently transcribed, and in some cases the incorporation in the " Literature " of
titles of important papers has been considered sufficient recognition of their authors' work.
We regret the introduction of Fol's Quadrille des Centres (notwithstanding the mention of the
adverse results obtained by Boveri, Wilson, and Mathews) and of the would-be corroborative
statements of Guignard. This and certain other very debatable topics might well have
been left aside, in preference say for a fitting recognition of substantial observations such as
Mitsukuri's upon the Mesoderm and Ccelom of the Chelonia and Haacke's and Giacomini's
upon the allantoir placenta of the Lacertilia. The scanty recognition of the Invertebrata has
been regarded as an objection to this work, it having been looked upon as ignoring
the great middle series which lie between man and the higher animals and the lower
organisms. This opinion appears to us to have arisen from a misconception of the author's
aims, and it is certainly less justified of the present edition than any of its predecessors.
The book deals professedly with the broader aspects of the organology of the vertebrata
and with cytological questions which largely border on the physiological and the study
of first principles ; and in these associations the lower animals appear to us to have
received ample consideration at the author's hands. His work is emphatically one for
medical students, and as meeting their demands it appears to us unequalled. It is now well-
established, and if the author would give us an edition in which illustrations, new and
numerous, should be of the same excellence as the text, he would confer a boon on medical
education.

Evolution in Art: as Illustrated by Life-Histories of Designs. By Alfred C. Haddon,
Professor of Zoology, Royal College of Science, Dublin. With 8 plates and 130 figures
in the text. The Contemporary Science Series. London : Walter Scott, Limited, 1895.

There is no training for a young biologist equal to a sojourn amongst the strange plants
and animals of a tropical region. Darwin in the Challenger, Huxley in the Rattlesnake,
received such a training and acquired the methods and material that made their reputations.
It is an education that gives the mind of the scientific worker a broad bent, and makes many
subjects have an interest for him. Before Professor Haddon made his journey to British New
Guinea and the adjacent coasts he was known as a zoologist, a geologist, and an embryologist,
but since then he has become better known as an anthropologist. It was his hap to land in a

D

xxxn SCIENCE PROGRESS.

region inhabited by mixed races of uncertain and puzzling origin, with strange customs and
habits, and, above all, with a crudely rich and elaborate style of ornamentation. It was
amongst the ornamental designs of those races that Professor Haddon commenced in earnest
a study of the life-histories of the designs found in native art, and the results of that study he
gave us in the form of a valuable memoir in the Cunningham Series of the Royal Irish
Academy. In this book the author has gone much further afield, and has written what is
practically an introduction to the study of decorative designs all the world over. His British
New Guinea researches form the nucleus of the book and give him the clue to many of his
deductions. The essence of his method may be said to lie in studying each design separately,
tracing its origin to some prototype, observing the meaning attached to it, working out its
life-history, noting the transmutations it undergoes, and collecting the intermediate forms of
the devices until he gets a series that connects the final meaningless conventionality with the
real and living form from which it has evolved. The material from which designs are drawn
gives him a basis for their classification. All designs, he finds, may be classified either under
zoomorphs, those derived from animal forms, or anthropomorphs, those obtained from human
forms, or phyllomorphs, those originating from plant forms, or physicomorphs, devices drawn
from the material universe, or skeuoworphs, decorations obtained from copying forms of
handiwork already in existence. From these sources, or a combination of them, often aided
by a fantastic imagination, saving perhaps some plain and geometrical designs, savage and
civilised people alike have drawn all their designs.

Nearly all the life-histories of designs given by the author are convincing and of extreme
interest. The crocodile device, the frigate-bird, the face, the scroll, the lotus flower, the
fylfot, and many other designs, are well worked out and amply illustrated. It is often
extremely difficult, sometimes impossible, to trace designs to their birth-places, although there
can be no doubt that a knowledge of the fauna, the flora, and ethnology of a district is of the
greatest assistance in the search. The author agrees with others in thinking that many of the
simpler designs may have arisen independently in different quarters of the globe, such, for
instance, as the scroll design.

A student of the more aesthetic side of art, however, might have some objections to offer
to certain parts of the book. He would object, probably, to the classification Professor Haddon
gives of the reasons for which objects are decorated. The reasons given are (i) for art, (2) for
information, (3) for wealth, and (4) for religion. Art here stands for any combination of line,
form, and colour, giving a pleasurable sensation. It is this pleasurable sensation that calls
all decorations into existence, and this is the only reason for the decoration of objects.
Information, wealth, and religion do preserve and keep designs and devices in existence,
but when designs become utilised with these significations they then cease in reality
to be decorations. Such a student might also carp somewhat at the title of the book ;
art and evolution have become words of so loose connotation that they are almost as
conventional and meaningless as some of the designs dealt with by the author. The
student of the aesthetic side of art, also, would be inclined to think that Professor Haddon
claims rather too much for Biology and its methods. It is quite true that designs are the
outcome of the living protoplasm of the human brain, but if for this reason biologists are to
claim art as a department of their subject, then must mathematics, physics, history, and every
science and art that the human mind deals with, fall to their share. Nor is there anything
peculiar in the methods of the biologist ; he uses his eyes, makes records, collects facts, and
draws deductions just as every other scientist does. But this book may be taken as a proof
that there is no reason why a biologist may not be a successful student of art and write a book
upon the subject charmingly free from all self-seeking, and making full and open acknowledg-
ment of the debt he owes to the observations and conclusions of men that have already worked
at this subject.

APPENDIX II.
CHEMICAL LITERATURE FOR MAY, 1896.

Vol. i. No. 5. American Journal of Science. (May, 1896.)

Trowbridge, J., Carbon and Oxygen in the Sun (pp. 329-333). Washingon, H. S., Ischian
Trachytes (pp. 375-386). Lea, M.C., Numerical Relations existing between the Atomic
Weights of the Elements (pp. 386-389). Palache, C, Crocoite from Tasmania (pp. 389-
39i)-

Vol. xviii. No. 5. Journal of the American Chemical Society. (May, 1896.)

De Chalmot, G., Hydrofluoric Acid (pp. 415-425). Coates, C. E., and Dodson, W. R.,
Nitrogen Assimilation in the Cotton Plant (pp. 425-428). Wiley, H. W., and Fwell,
E. E., Determination of Lactose in Milks by Double Dilution and Polarisation (pp. 428-
434). Venable, F. P., and Clarke, T., A Study of the Zirconates (pp. 434-445). Win ton
A. L., A Modified Ammonium Mobybdate Solution (pp. 445-446). Gladding, T. S.,
On the Estimation of Sulphur in Pyrites (pp. 446-449). De Schwei?iitz, E. A., and
Dorsett, M., Further Notes upon the Fats contained in the Tuberculosis Bacilli (pp.
449-451). Mclllhiney, P. C, The Cassel-Hinman Gold and Bromine Process (pp. 451-
457). Lord, N. W., A Simple Method for Determining the Neutrality of the Am-
monium Citrate Solution used in the Analysis of Fertilisers (pp. 457-458). Low, A. H.,
The Copper Assay by the Iodide Method (pp. 458-462). S/iorey, E. C, On Two Sources
of Error in Sugar House Analyses (pp. 462-466).

Vol. xviii. No. 4. American Chemical Journal. (April, 1896.)

Fay, H, The Action of Light on some Organic Acids in the Presence of Uranium Salts (pp.
269-290). Herty, C. H. , A Review of Some Recent Work on Double Halides (pp. 290-
294). Campbell, E. D., and Hart, E. B., On the Quantitative Determination of
Hydrogen by Means of Palladous Chloride (pp. 294-298). Jackson, C. L., and Calvert,
C. , On the Behaviour of Certain Derivatives of Benzol Containing Halogens (pp. 298-312).
Orndorff, W. R., and /Lowells, V. A., The Cis and Trans Modification of Benzene
Hexabromide (pp. 312-319). De Chalmot, G. , Silicide of Calcium (pp. 319-321). Jones,
H. C, and Allen, C. /?., The Conductivity of Yttrium Sulphate (pp. 321-323). Walker,
M. S., The Practical Use in the Chemical Laboratory of the Electric Arc obtained from
the Low Potential Alternating Current (pp. 323-328). Reiser, E. H. , The Preparation
of Allylene, the Action of Magnesium upon Organic Compounds (pp. 328-332).
Dunlap, F. L. , The Action of Urea and Sulphocarbanilide on Certain Acid Anhydrides
(pp. 332-341).

Vol. xviii. No. 5. (May, 1896.)

Remsen, I., and Muckenfuss, A. A/., Transformations of Parasulphaminebenzoic Acid under
the Influence of Heat (pp. 349-365). Kortright, F. L. , The Heat of Electrolytic Dis-
sociation of Some Acids (pp. 365-372). Lachmau, A., On the Existence of Pentaethyl
Nitrogen (pp. 372-375). Jones, H. C, and Allen, C. R., The Conductivity of Solutions
of Acetylene in Water (pp. 375-377). Jones, H. C, and Allen, C. R., The Use of
Phenolphthalein in Illustrating the Dissociating Action of Water (pp. 377-381).
Wheeler, H. L. , and Boltwood, B. B. , The Action of Acid Chlorides on the Silver Salts
of the Anilides (pp. 381-390). Howe, W. T. //., On the Existence of Two Orthophthalic
Acids (pp. 390-401). Morse, H. N. ; Hopkins, A. J.; and Walker, M. S., The
Reduction of Permanganic Acid by Manganese Superoxide (pp. 401-420).

Vol. xxi. No. 242. The Analyst. (May, 1896.)
Pearmain, T. H., and Moor, C. G., The Bacteriological Examination of Water for the
Typhoid Bacillus (pp. 117-122). Sykes, W. J., and Mitchell, C. A., The Estimation of
the Diastatic Power of Malt, etc. (pp, 122-128). Shepherd, H. H B., Official Methods
for the Analysis of Fertlizers, issued by the German Manure Manufacturers Association
(pp. 12S-133). Reed, L., Tropaeolins in Milk, etc. (p. 140).

xxxiv SCIENCE PROGRESS.

Vol. xv. No. 4. Journal of the Society of Chemical Industry. (30th April, 1896.)

Sindall, R. IV., Moisture in Wood Pulp (pp. 239-245). Smith, IV., A Study of Comparative
Affinities in the case of Certain Salts of Ammonium and Wool. II. (pp. 245-247). Her-
man, D., On Poisoning by Gas: its Prevention and Cure (pp. 247-248). Kohn, C. A., A
Modified Form of Schrotter's Apparatus for the Determination of Carbonic Anhydride
(p. 248). Beveridge, J., The Wood Cellulose Industry of Scandinavia (pp. 249-251).
Beveridge, J. , On a Method of Calculating the Amount of Steam required to Dry a Ton
of Paper or Pulp (pp. 251-252). Hart, P., Description of a Simple Feed- Water Heater
(pp. 252-253). Flintoff, R. J., The Functions of Albumin as a Fixing Agent for Pig-
ments on Cotton (pp. 253-254). Barnes, J. , On the Preparation of Water Free from
Ammonia (pp. 254-255). Clark. /., Estimation of Antimony in Ores and Metals (pp.
255-257). Dewey, F. P., The Sulphuric Acid Process of Refining Lixiviation Sulphides
(pp. 257-260).

Vol. xli. No. 252. Philosophical Magazine and Journal of Science.

(May, 1896.)

Shields, /. , A Mechanical Device for Performing the Temperature Corrections of Barometers
(pp. 406-414). Wood, R. IV., On the Absorption Spectrum of Solutions of Iodine and
Bromine above the Critical Temperature (pp. 423-431). Trowbridge, J., Carbon and
Oxygen in the Sun (pp. 450-454).

Vol. lix. No. 356. Proceedings of the Royal Society. (30th April, 1896.)

Wildermann, A/., A new Method of determining Freezing Points (pp. 251-254). Collie, J. N.
and Ramsay, W., On the Behaviour of Argon and Helium when submitted to the Electric
Discharge (pp. 257-270). Gamgee, A., On the Absorption of the extreme Violet and
ultra-Violet Rays of the Solar Spectrum by Haemoglobin, its Compounds, and certain of
its Derivatives (pp. 276-279).

Tome viii. Series 7. Annates de Chimie et de Physique. (May, 1896.)

Parenty, H. , Sur le d£bit des gaz parfaits et de la vapeur d'eau sous pression a travers les ori-
fices (pp. 5-79). I'aret, R., Recherches sur les sels de mercure (pp. 79-141). Moissan,
H., Etude sur l'argon (pp. 141-144).

Tomes xv.-xvi. No. 8. Bulletin de la Societe Chimique de Paris.

(20th April, 1896.)

Thomas, I '. , Action du peroxyde d'azote et de l'air sur le chlorure de bismuth (pp. 469-472).
Granger, A., Sur un sulfophosphure d'etain (pp. 472-474). Gnye, A., et Jordan, C,
Recherches expenmentales sur les butanol- 2- oi'ques (a-oxybutyrique) actifs (pp. 474-
498). Marie, £., Ethers glyceYiques des acides ceYotique et meEssique (pp. 498-503).
Marie, T., Chlorures d'acides, amides, nitriles des acides ceYotique et melissique (pp.
503-508). Marie, T., Sur l'oxydation des acides des graisses (pp. 508-510). Marie, T,
Sur les propri^tes des acides cerotique et melissique existant a l'etat libre dans la cire d'abeilles
(pp. 510-514). I 'a Ulan t, I r. , Sur quelques derives m^talliques de la dithioac£tylac£tone (pp.
514-519). Marcourt, £., Etude chimique d'un nouveau compost d'antipyrine at d'aldeEyde
formique (pp. 520-529). Reychler, A., Etude sur un dibromure de camphene (pp. 529-
530). Schenrer-Kestner, Sur la determination de l'acidit^ des produits pyroligneux (pp.
53°-536)-

Tomes xv.-xvi. No. 9. (5th May, 1896.)

Tassilly, Thermochimie. Etude thermique de quelques oxybromures (pp. 553-555). Guin-
chant, Lois de decomposition des sels par l'eau (pp. 555-560). Lepierre, C. , Analcime,
sa constitution (pp. 561-565). Marie, T., Sur les formules des acides cerotique et
melissique extraits de la cire d'abeilles (pp. 565-569). Marie, T., Derives bromes des
acides cerotique et melissique (pp. 569-575). Marie, T., Acides alcools et acides
amines derives des acides cerotique et melissique (pp. 576-583). Marie, T. , Derives
cyan£, anvidt5 et bibasique de l'acide cerotique (583-590). Marie, T., Comparaison entre
les denves des acids des cires et les denves des acides des graisses (pp. 590-591).
Bert rand, (',., Observations sur quelques nouveaux derives de la serie des pentoses ;
l'acide lixonique et la lixite (pp. 592-594). Barbier, P., et Bouveault, I.., Action du

ENUMERATION OF TITLES. xxxv

gaz chlorhydrique sur le licareol, le licarhodol et le temonol ; rapports entre ces trois
alcools (pp. 594-597). Gossart, E., Methode pour la recherche des falsification des
essences vegetates (pp. 597-609). Patent, G., et Dufau, E., Des combinaisons de
l'antipyrine avec les cresylols (pp. 609-610). Patein, G. et Dufau, L., Action de
l'antipyrine sur deux derives des diphenols (pp. 611-612). Bouckardat, G., et Tardy,
Sur l'essence d'anis de Russie (pp. 612-617).

Tome exxii. No. 15. Comptes Rendus hebdomadaires de V Academie des Sciences.

(13th April, 1896.)

Schloesing, T., Les nitrates dans les eaux de source (pp. 824-829). Grehant, A7., Sur les
produits de combustion d'un bee a acetylene — Melange explosifs d'acetylene et d'air
(pp. 832-833). Barbier, P., et Bouveault, L., Sur 1'homolinalcool et sur la constitution
du licareol et du licarhodol (pp. 842-844). Favrel, G., Action des cynaeetates de propyle,
de butyte et d' amyle sod£s, sur le chlorure de diazobenzene (pp. 844-846).

Tome exxii. No. 16. (20th April, 1896.)

Haller, A., Extraction des alcools terpeniques contenus dans les huiles essentielles (pp. 865-
869). Guye, P. A., et Jordan, C, Dispersion rotatoire des corps actifs liquides non
polymerises (pp. 883-886). Eerrand, Sur une nouvelle serie de sulfophosphures (pp. 886-
889).

\

Tome exxii. No. 17. (27th April, 1896.)

Guye, P. A., et Goudet, C, Superposition optique de six carbones asyme'triques dans une
meme molecule active (pp. 932-935). Didier, G., Sur un azotate basique de magnesie
(pp. 935-936). Granger, A., Sur le sesquiphosphure de fer cristallise" (pp. 936-937).
Gassmann, C, Etude sur le pendinitronaphtalene (pp. 937-940). Causse, H., Sur le
tartrate du phenyl - hydrazine et ses de'rivtis (pp. 940-943). Guinchant, Chaleur de
combustion des derives cyan^s (pp. 943-946). Sore!, A1., Sur la distillation des premiers
acides de la seYie grasse (pp. 946-948). Friedel, G. , Sur les zeolithes et la substitution
de diverses substances a l'eau qu'elles continnent (pp. 948-951). Henry, C, Sur la
determination par une methode photom^trique nouvelle, des lois de la sensibility
lumineuses aux noirs et aux gris (pp. 951-954). Gerardin, A,, et Nicloux, M., Mesure
des odeurs de Fair (pp. 954-955).

Tome exxii. No. 18. (4th May, 1896.)

Bertrand, J., Sur la theorie des gaz (pp. 963-967). Cazeneuve, P., Sur un nouveau mode de
preparation synth^tique de l'uree et des urees composers sym^triques (pp. 999-1000).
Arnaud, A., Transformation de l'acide taririque et de l'acide ste'arol^ique en acide
st£arique (pp. 1000-1002). Bourquelot, E., Sur la presence, dans le Monoiropa Hypopithys,
d'un glucoside de l'ether methylsalicylique et sur le ferment hydrolysant de ce glucoside
(pp. 1002-1004). Balland, Sur le mai's (pp. 1004-1006).

i6e Annee. Tome iii. No. 8. Journal de la Pharmacie et de Cliimie.

(15th April, 1896.)
Bourquelot, E., Sur l'hydrolyse du raffinose (melitose) (pp. 390-394). Maljean, Emulsion de
l'huile de houille par la poudre de marron d'Inde (pp. 394-395). Maljean, Quelques
dosages de matieres tanantes (pp. 395-396). Pruuier. /,., Essai des bromures officinaux
(pp. 396-400). Boinhardat, G., et Tardy, Sur l'essence d'anis de Russie (pp. 400-402).

i6e Annee. Tome iii. No. 9. (1st May, 1896.)
Causse, Sur le dosage du glucose (pp. 433-434). Pajot , Une falsification dans le commerce
des graines de colza (pp. 434-437). Chicote, C. , Note historique au sujet des vins platres
(PP- 437-438).

Tome xxviii. No. 2. Journal de la Societe Physico-Chimique Russe.
Hardin, D. , G. Porschneff (ne'crologie) (pp. 117-119). Lunge, G., A la mimoire du Dr. G.
Porschneff (pp. 119-120). Hinzberg, A., Sur la deshydratation du trioxyhexahydrocymol
(pp. 120-122). Ertschikoffsky, G. , Action de l'acide antique sur le pinfene (pp. 122-132).
Godlevski, /., Sur 1'oxydation du linionene (pp. 132-140). Lagorin, A.. Sur la forme
crystallographique de l'acide oxyterpenilique (pp. 140-143). Wagner, G., Recherche de

xxxvi SCIENCE PROGRESS.

l'agrostemme dans la farine (pp. 143-149). Reformatsky, S., Sur la preparation de l'acide
aa-dinie'thylglutarique (pp. 149-159). Dain, G., Action du zinc et de lather bromoiso-
butyrique sur l'aldehyde benzoique (pp. 159-175). Jacovkin, A., Sur la repartition d'un
compost entr£ deux dissolvants (pp. 175-186). Soboleff, A/., Sur les proprietes de l'acide
phospho- 12- wolframique (pp. 186-207). Beketoff, N. , Sur le changement du volume
ayant lieu lors de la formation de l'iodure d'argent en partant des elements ; Kournakoff,
N., Sur la structure des formes les plus complexes des composes chimiques ; Gvosda reff,
N., Sur les combinaisons ethylenediamidiques de palladium ; Zelinsky, A". , et Tchemos-
vitoff, Ar. , Sur les acides dimelhyltricarballyliques ; Rabinoz'ilsch, /., Analyse de l'eau
du lac sale de Golopristan ; Tschernik, G. , Sur un mineral ceritique du district de
Batoum ; Dementieff, A'., Dosage volumetrique du zinc (pp. 207-222).

Band ccxci. Heft 1 und 2. Justus Liebig's Annalender Chemie. (14th April, 1896.)
Graebe, C, und Stindt, H., Ueber Dibiphenylenathen und Dibiphenylathan (pp. 1-8).
Graebe, C, und Ullmann P., Ueber o- Aminobenzophenon (pp. 8-16). Graebe, C.
und Ullmann, P., Ueber eine neue Carbazolsynthese (pp. 16-17). Ullmann, F., Ueber
Reduction der o- Benzoyl- benzoesaure (pp. 17-25). Claisen, L., Beitrage zur Kenntniss
der 1, 3- Diketone und vervvandter Verbindungen. II. (pp. 25-137). Bruhl, J. W.,
Spectrochemische Untersuchung des a- und $- mesityloxydoxalsauren Methyls und
Aethyls von Claisen (pp. 137-147). Wislicenus, (I'., Uber die Isomerie der Formyl-
phenylessigester (pp. 147-217). Bruhl, J. IV., Spectrochemische Untersuchung des
a- und |8- Formylphenylessigesters (pp. 217-226). Wolff, L., Ueber Tetronsaure (pp.
226-252).

Band ccxci. Heft 3. (28th April, 1896.)

Kolb, A., Ueber einige Derivate des Phenylacetons (pp. 253-297). Einhorn, A., Ueber die
Reduction der Phenolcarbonsauren. II. (pp. 297-305). Hesse, O., Ueber die Wurzel von
Rumex nepa lens is (pp. 305-313). Zincke, T., Ueber Azimido- verbindungen IV. (pp.
313-342). Wallach, O., Zur Kenntniss der Terpene und der iitherischen Oele (pp.
342-367). Schiff, H., Benzalbiuret und verwandte Verbindungen (pp. 367-377)
Ostrogovich, A., Acetyl- und Benzoylbiuret (pp. 377-380).

Band ccxxxiv. Heft 4. Archiv de Pharmacie. (5th May, 1896.)

Peinemann, K., Beitrage zur pharmacognostichen und chemischen Kenntnis der Cubebe
und der als Verfalschung derselben beobachteten Piperaceenfruchte (pp. 241-272).
Lewin, L., Uber eine forensische Strychninuntersuchung (pp. 272-273). Kilia?ii, H.,
Ueber den Nachvveis der Digitalis-glycoside und ihrer Spaltungsprodukte durch
eisenhaltige Schwefelsaure (pp. 273-278). Mjden, J. A., Ueber das fette Oel des
Secale cornutum (pp. 278-283). Mjden, J. A., Ueber das fette Oel der Samen von
Strophantus hispidus (pp. 283-286). Mjden, J. A., Ueber das fette Oele der Samen von
Hyoscyamus niger (pp. 286-289). Balzer, A., Ueber das Sandaracharz (pp. 289-317).
Otto, R., Das Verhalten des Papaverins und Narkotins bei dem Stas - Otto'schen
Verfahren der Ausmittelung der Alkaloide (pp. 317-320).

Jahrgang xxix. No. 7. Benchte der Deutschen Chemischen GesellscJiaft,

(27th April, 1896.)

Jackson, C. L., und Corner, A. .)/., Ueber die Einwirkung von Salpetersaure auf Kaliumko-
balticyanid (pp. 1020-1023). Tiaube, /., Molekularvolumetrische Methode der Moleku-
largevvichts bestimmung. III. (pp. 1023-1030). Marchlewski, L., Zur Kenntniss des
Isatins (pp. 1030-1034). Tanatar, S., Ueber die Bildungsweise der Soda in der Natur
(pp. 1034-1039). Tanatar, S. , Notiz ueber untersalpetrige Sliure (pp. 1039-1040). Preyer,
W.\ Argon und Helium im Systeme der Elemente (pp. 1040-1042). Conrad, M. , Ueber
halogensubstituirte Acetessigester (pp. 1042-1048). Eckenroth, H., und Koerppen, G.,
Ueber einige Derivate des o- Benzoesauresulfinids (Saccharin) (pp. 1048-1052). Bamberger,
P., Berichtigung (pp. 1052-1053). Schuster, A., und Pin now, J., Ueber Derivate des
o-Diamidodimethylanilins (pp. 1053-1057). Hantzsch, A., und Gerilowski , D., Notiz
betr. die Ionenzahl der diazosulfonsauren Salze (pp. 1057-1059). Hantzsch, A., Zur
Kenntniss normaler Diazometallsalze (pp. 1059-1067). Hantzsch, A., Ueber das dia-
zonium (pp. 1067-1074). Gerilowski, D., Ueber stereoisomer Salze der Ortho-diazo-

ENUMERATION OF TITLES. xxxvn

benzol ortho-sulfonsiiure (pp. 1075-1078). Baeyer, A., Ortsbestimmungen in der
Terpenreihe (pp. 1078-1084). Paal, C, Ueber die Desamidirung des Glutinpeptons (pp.
1084-1095). Auwers, A'., Ueber Dibrompseudocumenolbromid und Analoge Verbindun-
gen (pp. 1095-1110). Auwers, K., und Ho/, L., Ueber Dibrompseudocumenolbromid,
-chlorid und -jodid (pp. 1110-1120). Auwers, K., und Senter, H, A., Ueber die
Umsetzungsproducte des Dibrompseudocumenolbromids mit aromatischen Basen (pp.
1120-1129). Auwers, K., und Camphenhausen, G. F, Ueber Bromderivate des as- m-
Xylenols (pp. 1129-1132). Lauin, J. M., Stereoisomere Thiodilactylsaure (pp. 1132-1136).
Lovifi, J. M., Ueber Thiodihydracrylsaure (Propansiiurethio- 3. 3- propansaure) und 8-
Sulfodipropionsaure (Propansaure- sulfon- 3. 3- propansiiure)(pp. 1136-1139). Lov'en, J. .1/.,
Einige in Bezug auf den Schwefel unsymmetrische Homologe der Thiodiglycolsaure und
der Sulfodiessigsiiure (pp. 1139-1134). Precht, /., Ueber eine Abhanderung der von Babo-
schen Wasserquecksilberlufthumpe zur Erzeugung hoher Luftverdiinnungen (pp. 1143-
1146). Werner, A., Ueber Stereoisomere bei Derivaten de Benzhydroxamsaure. III. (pp.
1146-1153). Werner, A., und Subak, J., Ueber Stereoisomere bei Derivaten der
Benzhydroxamsaure. IV. (pp. 1153-1161). Werner, A., und Gemeseus, A., Ueber
Aethylendihydroxylamin (pp. 1161-1164).

Jahrgang xxix. No. 8. (nth May, 1896.)

Curtius, T., und Cle/nm, H., Erstatz von Carboxyl durch Amid in mehrbasischen Sauren
(pp. 1166-1168). Schmidtmann, H, Ueber einige Derivate des Malonitrils (pp. 1168-
1175). Roth, W., Ueber B - Naphtyl- piperidin und B- Naphtyl- a- pipecolin (pp. 1175-
1182). Pictet, A., und Hubert, A, Ueber eine Neue Synthese der Phenanthridinbasen
(pp. 1182-1189). Pictet, A., Ueber eine eigenthiimliche Bildung des Acridons (pp. 1189-
1192). Fichter, F. , und Herbrand, A., Ueber eine neue Darstellungsweise einiger Lactone
der Fettreihe (pp. 1192-1195). Ginzberg, A., Ueber Sobrerol (A- Menthen- 2.8.- diol)
(pp. 1195-1198). Ginzberg, A., Zur Dehydratation des Menthan- 1.2.8- triols (pp. 1198-
1202). Tollens, B., Ueber den Nachvveis der Pentosen mittels der Phloroglucin- Salz-
saure- Absatz- Methode (pp. 1202-1210). Soderbaum, H. G., Neue Condensationspro-
ducte des Diphenyloxathylamins (pp. 1210-1216). Ciamician, G., und Si/ber, P., Zur
Kenntniss der Tropinsaure (pp. 1216-1218). Nef, J. W., Ueber die Einwirkung von
Aethylchloriden auf die Salz der Nitroparaffine (pp. 1218-1224). Goldschmidt, H., und
Girard, O., Kryoskopische Versuche mit Phenolsalzen (pp. 1224-1243). Gassmann, C,
Zur Kenntniss des Peridinitronaphtalins (pp. 1243-1246). Kehrmann, F., und Burgin,
H., Zur Constitution der Fluorindine. III. (pp. 1246-1254). Ladenburg, A., Das speci-
fische Drehungsvermogen der Pyroweinsiiure (pp. 1254-1255). Auwers, K., Ueber Inda-
zolderivate (pp. 1255-1272). Sondheimer, A., Zur Kenntniss eines Korpen mit acht-
gleidrigen Ringe (pp. 1272-1276). Bischoff, C. A., Studien ueber Verkettungen. VII.
Kuppelung von Malonsaureestern mittels einfacher Bindungen (pp. 1276-1280). Bischoff,
C. A., VIII. Kupplung von Malonsauredimethylestern mittels doppelter Bindung (pp. 1280-
1286). Bischoff, C. A., IX. Kupplung von Malonsiiurediathylester mittels doppelter
Bindung (pp. 1286-1293), Markcwald, W. , Ueber das Isopipecolin Ladenburg's (pp.
1293-1297). Tanatar, S., Die Umvvandlung des Trimethylens in Propylen (pp. 1297-
1300). Gabriel, S. , und Stelzner, R. , Zur Kenntniss der Chinazolinverbindungen (pp.
1300-1316). Krafft, F., und Weilandt, H., Siedetemperaturen beim Vacuum des
Kathodenlichts (pp. 1316-1328). Krafft, F, und Struts, A., Ueber das Verhalten
seifenahnlicher Substanzen gegen Wasser (pp. 1328-1334). Krafft, F., Ueber eine
Theorie der colloidalen Losungen (pp. 1334-1344).

Band liii. Nos. 6-7. Journal fiir Praktische Chemie. (10th April, 1896.)
Ipatiew, W., Ueber die Einwirkung von Brom auf tertiare Alkohole der Reihe (Cn H2n +2 O)
(pp. 257-288). Schneider, R. , Ueber das Atomgewicht des Wolframs (pp. 288-303).
Emery, W. O., Ueber zwei isomere Ketodicarbonsauren (pp. 303-308). Emery, W. O., Zur
Einwirkung von B- Bromlavulin- Saureester auf Natriummalonsaureester (pp. 308-312).
Emerv, W. 0.,Ubera- und B- Benzoyl- tricarballylsaureester (pp. 312-314). Thudicum,
J. L. W. , Ueber die Reactionen des Bilirubins mit Jod und Chloroform (pp. 314-325).
Claus, Ad., Zur Kenntniss des Carbostyrils und seiner Derivate, ein Beitrag zur
Losung der Tautomeriefrage (pp. 325-335). Clans, Ad., Zur Kenntniss des ana-
Oxychinolins (pp. 335-340). Zincke, T., Ueber o- Dinitroso- verbindungen der Benzolreihe
(pp. 340-344). Von Meyer, £., Zur Kenntniss des Mandelsaurenitrils (p. 344).

xxxvm SCIENCE PROGRESS.

Band xvii. Heft i. Monatshefte fiir Chemie und verwandte Thick andercr Wis-

senschaften. (March, 1896.)

Senkowski, M. , Zur Kenntniss der Constitution der Cholsiiure (pp. 1-4). Georgievics, G. v.
Zu Kenntniss der gefarbten Rosanilinbasen (pp. 4-13). Aleyerhojfer, IV., Ueber
reciproke Salzpaare I. (pp. 13-29). Alauthner, /., und Suida, IV., Beitrage zur
Kenntniss des Cholesterins III. (pp. 29-50). Eder, J. A/., und Valenta, £., Ueber drei
verschiedene Spectren des Argons (pp. 50-57). Jeiteles, B., Ueber die Destination von
0- Kresol mit Bleioxyd (pp. 57-65). Jeiteles, B., Notiz, ueber das Verhalten von
phenylsalicylsaurem Calcium bei der trochenen Destination (pp. 65-68). Lieben, A.,
Ueber die durch Einwirkung von alkoholischen Kali auf Aldehyde entstehenden
zweiwerthigen Alkohole (pp. 68-76). Just, A., Einwirkung von alkoholischen Kali auf
ein Gemenge von Formaldehyd und Isobutyraldehyd (pp. 76-85). Franke, A., Ueber
das aus dem Isobutyraldehyd entstehende Glykol und dessen Derivate (pp. 85-102).
Co/111, P., Ueber o- Benzoylphenol (pp. 102-109).

Jahrgang xxxv. Heft 2. Zeitschrift fiir A nalytische Chemie. (April, 1896.)

Behrens, H., Zur mikrochemischen Unterscheidung von Cinchonidin und Homocinchonidin
(pp. 133-143). Ruoss, Eine allgemeine volumetrische Bestimmung der durch fixe abzende
oder kohlensaure Alkalien fallbaren Metalle (pp. 143-159). Stutzer, A., und Maul, R.,
Untersuchung von Feinsprit auf dessen Gehalt an Fuselol (pp 159-163). Vaubel, II'., Zur
Gehaltsbestimmung von Benzidin und Tolidin (pp. 163-164). Vaubel, IV., Ueber das
Verhalten der Naphtole und Naphtylamine gegen nascirendes Brom (pp. 164-166).
Strohl, A., Jodzahl und Brechungsindex der Cacaobutter (pp. 166-169). Greiner und
Freidrichs, Arilometer- Pipette (pp. 169-170). Borntrdger, H., Ein Verfahren zur Auf-
losung des gegluhten Eisenoxydes und anderer Metalloxyde (p. 170). Fresenius, R., und
Hintz, R., Ueber eigenthiimliche Lbslichkeitsverhaltnisse des schvvefelsauren Baryts (pp.
170-184).

Band xii. Heft 1. Zeitschrift fiir A norganische Chemie. (nth April, 1896.)

Thomsen, J., Experimentelle Untersuchung ueber die Dichte des Wasserstoffes und des
Sauerstoffe (pp. 1-16). Sobolew, A/., Ueber einige physikalische Eigenschaften der Phos-
phor 1.2. Wolframsaure (pp. 16-39). Goldhammer, D. A., Bemerkungen ueber die
analytische Darstellung des periodischen Systems der Elemente(pp. 39-46). Werner, A.,
Ueber eine eigentiimliche Klasse von Platinverbindungen und die sogenannten isomeren
Platosoxalsiiuren (pp. 46-55). Hofmann, K. A., Erne" neue Persulfomolybdansaure (pp.
55-63)-

Band xix. Heft 4. Zeitschrift fiir Physikalische Chemie. (1st May, 1896.)

Luther, L., Elektromotorische Kraft und Verteilungsgleichgewicht (pp. 529-572). Ihle, R.,
Ueber die Bildung von Ammoniak bei der Elektrolyse der Saltpetersaure (pp. 572-577).
Ihle, R., Ueber die katalytische Wirkung der salpetrigen Silure und das Polential der
Salpetersaure (pp. 577-592). Tafel, /.. Ueber die sogenannte " indirekte Esterbildung "
(pp. 592-599). Noyes, A. A., Die katalytische Wirkung der Wasserstoffionen auf poly-
molekular Reaktionen (pp. 599-607). IVald, F., Die Genesis der stochiometrischen
Grundgesetze. II. (pp. 607-625). Kenrich, F. B., Die Potentialspriinge zwischen Gasen
und Fliissigkeiten (pp. 625-657). Friedliinder, S., Ueber Argon (pp. 657-668). Wagner,
M., Die Zersetzungsgeschwindigkeiten der Schwefel-stickstoffsauren (pp. 668-689).
Wood, R. W., Ueber die Absorptionsspektren der Lbsungen von Jod und Brom ueber
der Kritrischen Temperatur (pp. 689-696). Tanatar, S., Die Losungs- und Neutralisa-
tionswarme des Nitroharnstoffes und seines Kaliumsalzer (pp. 696-699). Schall, C, Nach-
trag zur letzten Abhandlung (pp. 699-709).

Anno xxvi. Vol. i. Fascicolo 2. Gazzetta Chimica Italiana. (22nd March, 1896.)

Moro, P., Ricerche sull'acido naftalindicarbonico 1-5 e suoi derivati (pp. 89-116). Zoppellari,
I., Sopra alcuni fenomeni osservati nel congelamento di soluzioni diluite (pp. 116-119).
Carrara, G., Per la teoria della dissociazione elettrolitica in solventi diversi dall'aqu. I.
Alcool metitico (pp. 1 19-197).

ENUMERATION OF TITLES. xxxix

Anno xxvi. Vol. i. Fascicolo 3. (6th April, 1896.)

Errera, G., Metodo generale di preparazione delle a- bialchilidantoine (pp. 197-211). Antony,
U., e Lucckesi, A., Considerazioni per la precipitazione di solfuri di platino. Solfuro
diplatinocolloidale(pp. 211-218). Antony, U.,eBenelli, T., Ricerca delle piccole quantita
di piombo nelle acque (pp. 218-220). Tarugi, N., Per la ricerca dei cromati e degli
arseniti (pp. 220-222). Grande, E., Contribuzione alia conoscenza degli eteri della
fenolftaleina (pp. 222-231). Gennari, G., Sulla velocita di saponificazione in solventi
organici (pp. 231-237). Salvado?-i, R., Dissociazione elettrolitica in relazione colle vari-
azioni della temperatura. I. Studi crioscopici ea ebullioscopici sopra le soluzioni acquose
ed in alcool melitico di alcuni cloruri (pp. 237-255). Zoppellari, I. , Sopra il comporta-
mento crioscopici e la composizione di alcuni acetati di basi deboli (pp. 255-264). Errera,
G., e Berte, E., Derivati della fenolftaleina (pp. 264-274). Longi,A., e Mazzoliiw, G.,
Sulla prebesa combinazione del cianoforme coll'joduro mercurico (pp. 274-280).

APPENDIX I.

NOTICES OF BOOKS.

Grundriss der Krystallographie fur Studirende und zum Selbstunterricht. By Gottlob Linck.

Jena, 1896. Pp. vi. and 252.

The great and ever-increasing importance of the position held by crystallography as an
auxiliary to the kindred sciences of physics and chemistry is gradually receiving recognition.
Indications are not wanting that in the future many of the problems of molecular physics
relating to solid bodies will be found easily susceptible to attack by crystallographic methods,
so that crystallography will at length take its legitimate position as a branch of physical
chemistry. With these prospects, we gladly welcome any book in which crystallography is
rationally discussed as a living science, which embraces a remarkably fertile and hitherto com-
paratively unexploited field.

In the preface to the present volume, the author states that his work is designed for the
perusal of young students ; and, in spite of what appear to us serious defects, the book is of an
extremely readable character, and its language so clear and simple, that the author's design
is, on the whole, well carried out. We find, however, no mention of the stereographic
projection throughout the work, and an English reader can scarcely conceive of a student
attaining to an appreciative grasp of elementary crystallography, without early acquiring an
easy facility in the use of that simple and invaluable aid. Surely, too, the time has come when
Naumann's cumbrous method of describing forms might well be consigned to the crystallo-
graphic historian, and be entirely omitted from educational works. Here, however, the author
assigns to it equal prominence with the more significant and elegant Millerian method.

That portion of the work which deals with the geometrical properties of crystals is
concise and well arranged. The method of treating the hexagonal system is, however,
unsatisfactory, the reader being left with very vague notions respecting the precise meaning and
character of the axial system employed. The treatment of crystallographic optics is clear, and,
for an elementary manual, leaves little to be desired. The chapter dealing with polymorphism,
isomorphism, morphotropy, etc., is a very praiseworthy innovation in a work of this kind ; it
treats briefly and concisely of the relations existing between chemical composition and
crystalline form.

The book is well printed and amply illustrated with diagrams of a distinctly superior
character to those which we are accustomed to see copied from one work into another, ad
nauseum ; a coloured diagram of interference figures ends the book.

The following list of errata may be of service : —

P. 6, line 12 from below, read Krystallsystem.

.. 36>

, 14 .

, above,

, Triakisoctaeder.

.. 43.

. !7

, below,

, , einander.

,, 64,

. 11

, above,

, Nebensym.

,,188,

. 9 .

, below,

, chroi'smus.

..19°.

, 18 ,

■ 1 .

, Mg Al2 04.

.. 192,

. 21

, above,

,, nach.

11 it

. 35 •

■ 11

, convergent.

..193.

, 16 ,

1 . >

, gewohnlichem.

..195.

. 22 ,

, below,

, differenz.

.,198,

. 33 .

, above,

, 441.

.■203,

, 14 .

, isotropen.

, , 240,

. 13 ■

, below, ,

, Ausloschungs.

E

APPENDIX II.

CHEMICAL LITERATURE FOR JUNE, 1896.

Vol. xxi. No. 243. The Analyst. (June, 1896.)

Pearmain, T. H., and Moor, C. G., The Bacteriological Examination of Water for the
Typhoid Bacillus (pp. 141-148). Smith, H. M., Note on the Estimation of Formic
Aldehyde (pp. 148-151). Shepherd, H. H. /?., Official Methods for the Analysis of
Fertilizers, issued by the German Manure Manufacturer's Association (pp. 151-156).
McGill, H., Note on the Use of the Westphal Balance (pp. 156-157). Leonard, N.,
Note on Hehner's Test for Formic Aldehyde (pp. 157-158).

Vol. lxix. No. 402. Journal of the Chemical Society. (May, 1896.)

Collie, J. N., and Wilsmore, N. T. M., The Production of Naphthalene and of Isoquino-
line Derivatives from Dehydracetic Acid (pp. 293-304). Lapworth, A., and Kipping, F.
S., Isomeric ir-Bromo-a-Nitrocamphors (pp. 304-322). Lapworth, A., Note on the
Formation of Camphorquinone from a-Chloronitrocamphor (pp. 322-324). Doran, R. £.,
The Action of Lead Thiocyanate on the Chlorocarbonates. I., Carboxyethylthicarbimide
and its Derivatives (pp. 324-344). Tut/on, A. £., Connection between the Atomic
Weight of Contained Metals and the Crystallographical Character of Isomorphous
Salts. The Volume and Optical Relationships of the Potassium, Rubidium and
Caesium Salts of the Monoclinic Series of Double Sulphates R2 . M . (S04)2. 6H20 (pp. 344-
495). Tutton, A. £., Comparison of the Results of the Investigation of the Simple and
Double Sulphates containing Potassium, Rubidium, and Caesium and General Deduc-
tions therefrom Concerning the Influence of Atomic Weight on Crystal Characters
(pp. 495-507). Tutton, A. E., The bearing of the Results of the Investigations of the
Simple and Double Sulphates containing Potassium, Rubidium and Caesium on the
Nature of the Structural Unit (pp. 507-526). Law, R., An Auxiliary Assay Balance
(pp. 526-530). Ruhemann, S., and Tyler, E. A., Contributions to the Knowledge of
Ethylic Acetoacetate. I., Acetonylmalic Acid (pp. 530-536). Burrell, B. A., Analysis of
the Water from the Dropping Well at Knaresborough, in Yorkshire (pp. 536-539).
Wood, T. B., Spivey, IV. T. AT. , and Easterficld, T. H., Charas. The Resin of
Indian Hemp (pp. 539-546). Eenton, H. J. H., The Constitution of a new Dibasic acid,
resulting from the Oxidation of Tartaric acid (pp. 546-563). Presidential Address
(PP- 563-57I)-

Vol. xv. No. 5. Journal of the Society of Chemical Industry. (30th May, 1896.)

Cross, C. F., and Bevan, E. J., Artificial Silk (Lustro-Cellulose) (pp. 317-319). Orsman, IV.
J., The Action of Carbon Monoxide and Coal Dust in Promoting Colliery Explosions
(pp. 319-320). Clayton, G. C, Chlorine as a Disinfectant (pp. 320-322). Carey, E.,
Exports of Heavy Chemicals (p. 322). Hogg, T. IV., On Blister Steel and some Points
concerning its Formation (pp. 323-325). Carulla, F. J. R., The Corrosion of Iron by
Raw Tar (pp. 325-326). Archbutt, L. , An Evaporation Test for Mineral Lubricating
Oil (pp. 326-328). Richardson, F. IV., and Aykrbyd, H. E., " Cachon de Laval"
(pp. 328-332). Hendrick, J., Experiments with Bordeaux Mixture as a Preventive against
Potato Disease (pp. 332-335). Stewart, D. R., The Standard of Flash-Point for
Mineral Oil (pp. 335-336). Hawkins, J. D. , The Chlorination of the Gold Ores (pp.
336-339)- Love, E. G., The Effect of Compression of Illuminating Gas upon its Candle-
Power (pp. 339-340).

Vol. xli. No. 253. Philosophical Magazine and Journal of Science. (June, 1896.)

Mcintosh, D., On the Calculation of the Conductivity of Mixtures of Electrolytes having a
common Ion (pp. 510-517). Roberts-Austen, IV. C, On the Diffusion of Metals (pp.
524-528).

ENUMERATION OF TITLES. xliii

Tome viii. Series 7. Annates de Chimie et de Physique. (June, 1896.)

Limb, C, Mesure directe des forces eiectromotrices en unites absolues eiectromagnetiques (pp.
145-240). Varet, R. , Recherches sur les combin.iisons du cyanure de mercure avec les
sels halogenes (pp. 240-288).

Tomes xv.-xvi. No. 10. Bulletin de la Societe Chimique de Paris. (20th May,

1896.)

Moureu, C, Sur la presence de l'argon et de l'heiium dans une source d'azote naturelle (pp.
626-627). Bertrand, G., Preparation biochimique du sorbose (pp. 627-631). Meunier, /.,
Sur le dichloralglucose et sur le monochloralglucosane (pp. 631-633). Rousset, L., Action
des chlorures d'acides sur les Others oxydes des naphtols en presence du chlorure d'alumi-
nium (pp. 633-638). Reverdin, F., Sur quelques derives iodes de 1'anisol et sur un cas de
migration de I'atome d'iode (pp. 638-646). Mouren, C, Sur la veratrylamine (pp. 646-
651). Moureu, C. , Synthese du methyleugenol. Constitution de l'eugenol (pp. 651-654).
Moureu, C„ Sur la methylene-pyrocatechine (pp. 654-656). Moureu, C, Synthese de
l'isosafrol. Constitution du safrol et de l'isosafrol (pp. 656-661). Causse, H., Sur le
tartrate de phenylhydrazine et ses derives (pp. 661-666). Gossart, E., Methode pour la
recherche des falsifications des essences vt?gt§tales (pp. 666-688).

Tomes xv.-xvi. No. 11. (5th June, 1896.)

Senderens, J. B., Action du fer sur les azotates metalliques en dissolution. Allotropie et
passivity du fer (pp. 691-700). Deh'pine, A/., Sur une nouvelle methode de separation des
methylamines (pp. 701-714). Cazeneuve, P., Sur un nouveau mode de preparation syn-
thetique de 1'uree et des urees composers symetriques (pp. 714-715). Collet, A., Action
du chlorure de propionyle a-brome sur le benzene en presence du chlorure d'aluminium
(pp. 715-717). Prudhomme, A/., Condensation d'hydrols et d'amines aromatiques en
presence d'acide sulfuri^ue concentre (pp. 717-720). PrucChomme, AI., Sur les parafuch-
sines benzylees (pp. 720-723). Cazeneuve, P., Sur un caractere distinctif de la fuchsine
ordinaire et de la fuchsine acide S. Sur la reaction de Schiff (pp. 723-724). Gossart, F...
Methode pour la recherche des falsifications des essences vtfgtitales III. (pp. 724-742).

Tome exxii. No. 19. Comptes Rendus hebdoniadaires de VAcademle des Sciences.

(nth May, 1896.)

Schloesing, T. , Les nitrates dans les eaux potables (pp. 1030-1038). /-lesson, A., Action du
gaz bromhydrique sur le chlorure de thiophosphoryle (pp. 1057-1060). Thomas, /'., Action
de 1'air et du peroxyde d'azote sur quelques composes halogenes du bismuth (pp. 1060-
10621. Bouveault, L., Action du chlorure d'ethyloxabyle sur les hydrocarbures aroma-
tiques en presence du chlorure d'aluminium (pp. 1062-1064). Delepine, A/., Sur une
nouvelle methode de separation de methylamines (pp. 1064-1066).

Tome exxii. No. 20. (18th May, 1896.)
Bertrand, J., Note sur la theorie des gaz II. (pp. 1083-1085). A/oissan, H., Preparation et
proprietes de l'uranium (pp. 1088-1093). Chauveau, A., Sur la transformation de la graisse
en hydrate de carbone dans l'organisme des animaux non alimentes (pp. 1098-1103).
Tommasi, D., Sur un nouvel electrolyseur (pp. 1122-1123). Caret, P., Recherches sur le
cyanure de nickel (pp. 1123-1125). Dufau, E., Surun tetrachromite de baryoum cristallise
(pp. 1125-1127). Han riot, Sur les chloraloses (pp. 1127-1130). Cazeneuve et Moureu, Sur
quelques urees aromatiques symetriques (pp. 1130-1132). Bertrand, G., Sur les rapports
que existent entre la constitution chimique des composes organiques et leur oxydabilite
sous l'influence de la laccase (pp. 1132-1135). l.indet, L., Caracterisation et separation
des principaux acides contenus dans les vegetaux (pp. 1135-1137).

Tome exxii. No. 21. (26th May, 1896.)

Boltzmann. Sur la theorie des gaz (pp. 1173-1174). Raoult, F. A/., Sur les tensions de
vapeur des dissolutions faites dans l'acide formique (pp. 1175-1177). Besson, A., Action
du gaz iodhydrique et de l'iodure de phosphonium sur le chlorure de thiophosphoryle (pp.
1200-1202). Delacre, A/. , Sur l'hydratation de la pinacoline (pp. 1202-1206). Cazeneuve,
P. , Sur un nouveau mode de preparation de l'acide glycerique (pp. 1206-1207. Beauveault,
L. , Action du chlorure d'ethyloxalyle sur les hydrocarbures aromatiques en presence du-
chlorure d'aluminium (pp. 1207-1209). Guinchant, Nouveaux derives des ethers cyanaceti

xliv SCIENCE PROGRESS.

ques (pp. 1209-1212). Ber/ra?id, G., Sur une nouvelle oxydase, ou ferment soluble
oxydant, d'origine vegetale (pp. 1215-1218).

Tome cxxii. No. 22. (1st June, 1896.)

Moissan, H,, et Moureu, C, Action de l'acEtylene sur le fer, le nickel et le cobalt recluits par
l'hydrogene (pp. 1240-1244). Guichard, A/., Sur la molybdenite et la preparation du
molybdene (pp. 1260-1272). Del'epine, Sur les methylamines (pp. 1272-1274). Causse,
H., Sur les ald£hydates de phenylhydrazine (pp. 1274-1277).

i6e Annee. Tome iii. No. 10. Journal de la Pharmacie et de Chitnie.

(15th May, 1896.)

Cazenenve, P. , Sur un nouveau mode de preparation synth^tique de l'uree et des urees com-
poses symftriques (pp. 481-482). Marie, 7'., Sur quelques derives des acides cerotique
et melissique (pp. 482-488). Klobb, T., Sur quelques nouvenux derives des ethers
cyanacetiques (pp. 488-491). Mallat, .-/., Echelle alcaline des eaux minerales naturelles
du bassin de Vichy (pp. 491-493).

i6e Annee. Tome iii. No. 11. (1st June, 1896.)

Petit, A., et Terra., P., Sur le dosage de la cafeine dans le th£ (pp. 539-534). Marie, T.,
Comparais'on entre les derives des acides des cires et les derives des acides des graisses (pp.
534-536). Soulard, Analyse d'un liquide pleureUque (pp. 536-539). Lafay, L., Analyse
d'un liquide de tumeur parotidienne ; Epithelioma glandulaire lobule (pp. 539-543).
Moulin, /.. , Sur une reaction nouvelle de l'asparagine (p. 543).

Tome xxviii. No. 3. Journal de la Societe Physico-Chimique Russe.

Sapoch?iikoff, A., Sur les proprietes des solutions aqueuses de l'acelone (pp. 223-278).
Markowriikoff, IV'., Sur la source minerale de Narzane (pp. 278-283). Andres, L., Action
du zinc et de l'Ether bromobutyrique sur 1'aldehyde benzoique (pp. 283-293). C uenhesko ,
/., Synthese de l'acide dimethylisobutylenelactique (pp. 293-299). Melikoff, P., Analyse
du meteorite de zmen (pp. 299-307). Melikoff, P. , Sur les conditions de la formation de
la soude naturelle (pp. 307-311). Ipatieff, II'., Action du zinc sur les bromures du
dimethyltrimethylene, du trimethylethylene et de l'isopropylethylene. Ipatieff, II'.,
Sur le diethylallene. Ipatieff, W., et Wiltorf, A'., Sur la combinaison de Pisoprene
avec l'acide bromhydrique. 7,elinsky, A'., et Generosoff, A., Sur le methylhexamethylene.
Zelinsky, N., et Issaeff, II'., Acide dimethyldioxyadipique. Zelinsky, N. , et Br u ha men ko,
Influence du souffre sur la refraction de Tether tioamylique. Gorboff, A., Une note.
Konovaloff, D., Sur l'amalgame de l'alluminium. Koiuwaloff, D., Sur l'etherification de
l'acide oxalique. Autipoff, J. , Sur le pyrites contenant du thallium. Tanatar, S. , Sur
l'acide hypoasiotique. Tanatar, S., Formation de la soude naturelle. Barilowitse/i , A.,
Synthese de l'acide dime'thyloxypelargonique (pp. 311-328.

Jahrgang xxix. No. 9. Berichte der Deutschen Chemischen Gesellschaft.

(8th June, 1896.)

Palmer, A. H'.,und Bi-enke, IV. C, Ueber symmetrisches Triamidotoluol (pp. 1346-1347).
Sckunek, E., und Marchlewski, L. , Zur Chemie des Chlorophylls (pp. 1347-1352.
Vorldnder, D., und Hobohm, A'. , Ueber die Einwirkung von Benzaldehyd auf Diathylketon
(pp. 1352-1354). Schiff, H., Ueber Desamidoalbumin (pp. 1354. 1356). Niementowski,
SI., Zur Kenntniss der Oxydationsvorgiinge in der Chinazolinreihe (pp. 1356-1361).
Goldschmidt, C, Ueber die Einwirkung von Formaldehyd auf Phenylhydrazin in saurer
Losung (pp. 1361-1362). Unger, O., und Hofmann, K. A., Zur Kenntniss des
Thiodiphenylamins (pp. 1362-1369). Goldsehmidt, H., und Reinders, R. U., Unter-
suchungen ueber die Geschwindigkeit des Uebergangs von Diazoamidokbsperm in
Amido-azoverbindungen (pp. 1369-1377). Fischer, P.. , Configuration der Weinsaure
(pp. 1377-1383). Bamberger, E., Ueber die Zusammensetzung der Isodiazohydroxyde
(pp. 1383-1388). Bamberger, E.. Schlusserklarung (pp. 1388-1390). Lob, IV., Neue
Arbeitsmethoden der organischen Chemie (pp. 1390-1392). Winterstein, E., Ueber das
Oxim des salzsauren Glucosamins (pp. 1392-1394). Hantzsch, A., Vorltiufige Notiz
ueber untersalpetrige Siiure (p. 1394). Traute, J., Ueber Racemie (pp. 1394-1397).
Meyer, V., Notizen zur Chemie der Esterbildung (pp. 1397-1402). Weisse, K., Ueber
die Einfiihrung eines vierten Radicals an Stelle von Hydroxyl in das Triphenylcarbinol

ENUMERATION OF TITLES. xlv

(pp. 1402-1404). Hirtz, H., Ueber die Einwirkung von Brom auf aromatische Jodverbin-
dungen (pp. 1404-1411). Meyer, V., und Pemsel, W., Notiz ueber eine eigenthiimliche
Zersetzung des Dijodacetylens (pp. 1411-1413). Meyer, V., Ueber Diacetylmesitylen
(pp. 1413-1415). Kehrmann, /<". . und Hertz, AL, Ueber den Einfluss der Substituenten
auf die Oximbildung der Chinine (pp. 1415-1420). Luchmann, A., Beitrage zur
Kenntniss der halogenisirten Amine der Fettreihe (pp. 1420-1434). Bromberg, O., Zur
Kenntniss der Phtalazin derivate (pp. 1434-1442). Nietzki, R., Die Constitution der
Safranine (pp. 1442-1446). Haeussermann, C, und Leichmann, H., Ueber einig-
Abkbmmlinge des Phenylathers (pp. 1446-1450). Francis, F. E., Ueber Orthodinitroe
benzylbenzidin und einige Derivate (pp. 1450-1454; Ludwig,E., Ozonhaltige Aldehyde
zum Nachweise minimalster Mengen Jod neben Chlor und Brom (pp. 1454-1457). Cross,
C. F., Bevan, G. /., and Smith, C, Die Constitution der Cellulosen der Cerealien (pp.
1457-1462). v. Miller W. und Plochl, J., Zur Stereochemie der Stickstoffverbindungen
(pp. 1462-1473). Goldschmidt, C, Ueber die Einwirkung von Formaldebyd auf im- Methyl
phenylhydrazin in saurer Lbsung (pp. 1473-1474). Dermstaedter, L. und Lifschiitz, J.,
Beitrage zur Kenntniss der Zusammensetzung der Wollfettes (pp. 1474-1477). Tanatar,
S., Fumiirsaures Hydroxylamin und dessen Zersetzungsproducte (pp. 1477-1479). Born-
stein, £., Ueber die Einwirkung von Benzolsulfochlorid auf Nitrosodimethylanilin (pp.
1479-1488). v. Kostanecki, SI. und Rossbach, G., Ueber die Einwirkung von Benzaldehyd
auf Acetophenon (pp. 1488-1495). v. Kostanecki, SI. und Tamber, J. , Ueber die Einwir-
kung von Alkalien auf Benzalacetophenon und Benzaldiacetophenon (pp. 1495-1497).
Hinsbeig, O. und Roller, P., Ueber die Einwirkung der Aldehyde auf aromatische Ortho-
diamine IV. (pp. 1497-1504). Bischoff, C. A., Studien ueber Verkettungen, X. Cdmbina-
tionen, welche zu Estern der Methylacetylentetracarbonsaure (Butansaure -2- methylsaure
-3- dimethylsaure) fuhren sollten (pp. 1504-1514). Bischoff, C. A., Studien ueber Verket-
tungen, XI. Combinationen, welche zu Aethylacetylentetracarbonsaureester (Pentansaure
-2- methylsaure -3- dimethylsaureester) fuhren sollten (pp. 1514-1521). Gassmann, C.,
Zur Bildung der Binitronaphtaline, II. (pp. 1521-1522). Hantzsch, A. und Davidson, W.
B., Ueber Diazophenole (pp. 1522- 1536. Paal, C., Berichtigung (p. 1536).

Band xvii. Heft 2. Monatshefte fur Chemie und vcrwandtc Thiclc andevcr
Wissmshaftcn. (23rd April, 1896.)

Wegscheider, R. , Ueber das Verhalten der Opiansaure und ihrer Ester gegen einige Alde-
hydreactionen (pp. 111-121). Elmer, V. v. , Weitere Versuche ueber die Umkehrung der
Doppelbrechung ieimgebender Gewebe durch Reagentien (pp. 121-126). Kohn, L.,
Ueber die Einwirkung des alkoholischen Kalis auf den Isovaleraldehyd (pp. 126-149).
Reich, A., Synthetische Versuche in der Terpentinreihe (pp. 149-172). Weidel, H., und
Roithner, E., Ueber den Abbau einiger Saureamide (pp. 172-191). Herzig, J., Ueber
eine Isomerie beim Acetylaurin (pp. 191-199), Schrolter, H., Beitrage zur Kenntniss der
Albumosen. III. (pp. 199-205).

Band xii. Heft 2. Zcitschrift fiir Anorganische Chemie. (gth May, 1896.)

Sulc, O., Ueber das sogenannte elektrolytische Silbersuperoxyd (pp. 89-98). Re/gers, J. W„
Ueber die Stellung des Tellurs im periodischen Systeme (pp. 98-118). Gooch, F. A.,
und Peirce, A. W., Ueber eine Methode zur Trennung des Selens vom Tellur, beruhend
auf der verschiedenen Fluchtigkeit ihrer Bromide (pp. 1181-24). Jannasch, P., und
Lehnert, H., Ueber quantitative Metalltrennungen in Alkalischer Lbsung durch
Wasserstoffsuperoxyd (pp. 124-129). Jannasch, P., und Lehnert, H., Ueber die
Ber,timmung des Schwefels in anorganischen Sulfiden durch Gliihen derselben in einem
Sauerstoffstrome und Auffangen der fliichtigen Oxyde in Wasserstoffsuperoxyd (pp. 129-
132). Jannasch, P., und Lehnert, H., Trennung des Quecksilbens von anderen Metallen
durch Gliihen ihrer Sulfide in einem Sauerstoffstrome (pp. 132-134). Jannasch, P., Ueber
Trennungen des Mangans von Kupfer und Zink, (Wasserstofthyperoxydmethode),
sowie des Kupfers von Zink und Nickel (Schwefelwasserstoff und Rhodanmethode)
nebst erganzenden Bemerkungen (pp. 134-143). Jannasch, P., Ueber eine empfindlich
form der Quecksilberjodidreaktion (pp. 143-146). Hofmann, K. A., Ueber das Nitro-
prussidnatrium (pp. 146-168).

Band xii. Heft 3. (6th June, 1896.)
Piccini, A., Die Superoxyde in Beziehung zu dem periodischen System der Elemente (pp.
169-180). Side, O., Ueber das sogenannte elektrolytische Silbersuperoxyd (pp. 180-182).

xlvi SCIENCE PROGRESS.

Flawitzky, F., Eine Hypothese ueber die Atombewegung der Elemente und die Entste-
hung der letzteren (pp. 182-188). Larsson, A., Untersuchungen ueber Niob (pp. 188-208).
Jannasch, P., und Heidenreich, O., Ueber die Aufschliefsung der Silikate durch Borsaure
II. (pp. 208-219). Jannasch, P., Ueber das Verhalten der Mineralien der Andalusit-
gruppe gegen Aufschliefsungsmittel I. (pp. 219-223). Jannasch, P., Eine neue Methode
der Ueberfiihrung von Sulfaten in Chloride (pp. 223-225). Arctowski, H., Versuche
Ueber die Fliichtigkeit des roten Phosphors (pp. 225-229).

Band xx. Heft 1. Zeitschrift ' fiir Physikalische Chemie. (29th May, 1896.)

Rogdyski, A"., und Tammann, G., Ueber adiabatische Volumenanderungen an Losungen (pp.
1-19). Jakowkin, A. A., Ueber die Dissociation polyhalogener Metallverbindungen in
wasseriger Losung (pp. 19-40). Whitney, W. R., Untersuchungen ueber Chromsulfat
Verbindungen (pp. 40-68). Morley, E. IV., Ueber die Dichten von Sauerstoff und
Wasserstoff und ueber das Verhaltnis ihres Atomgewichte (pp. 68-131). Linebarger, C.
F.., Ueber die Dielektrizitatskonstanten von Fliissigkeitsgemischen (pp. 131-139).

Anno xxvi. Vol. 1. Fascic. iv. Gazzetta Chimica Italiana. (16th May, 1896.)

Feliciani, G, Analisi chimica dell'acqua acetosa di Roma (Ponte Motle) (pp. 281-289). Lam-
berti-Zanardi, Azione del cloro sul benzoilnitrocarbazol (pp. 289-293). Antony, U., e
Gigli, G., Sulla decomposizione idrolitica del nitrato e del solfato ferrico (pp. 293-311).
Zanninoivich, T. W., Dissociazione eleltrolitica delle soluzioni in acido formico (pp. 311-
323). Ponzio, G., Sulla preparazione dei senfoli alifalici e sul leso compostamento con
l'idrogeno solforato (pp. 323-327). Longi, A., e Bonaria, L., Sulle determinazioni volume
trische del piombo (pp. 327-403).

APPENDIX.

CHEMICAL LITERATURE FOR JUNE, 1896.

Vol. xviii. No. 6. American Chemical Journal. (June, 1896.)

Linebarger, C. E., On the Specific Gravities of Mixtures of Normal Liquids (pp. 429-453).
Orndorff, W. R., and Bliss, C. L., Dianthranol — A Dihydroxyl Derivative of Dian-
thracene (pp. 453-465). Jackson, C. L., and Calvert, S., Bromine Derivatives of Meta-
phenylene Diamine (pp. 465-490). Bushong, F. IV. , On Benzimidoethyl and Benzimido-
methyl Ethers (pp. 490-491). /Castle, J. H., Reiser, B. C, and Bradley, £., On the
Halogen Derivatives of the Sulphonamides (pp. 491-502). Slickney, D., The Reduction
of Copper Sulphide (pp. 502-504).

Vol. xviii. No. 6. Journal of the American Chemical Society. (June, 1896.)

Ewell, E. E. , and Wiley, H. W. , The Effect of Acidity on the Development of the N itrifying
Organisms (pp. 475-484). Lads, A. K., Standard Prisms in Water Analysis and the
Valuation of Color in Potable Waters (pp. 484-491). Bryant, A. P., A Method for
Separating the " Insoluble" Phosphoric Acid in Mixed Fertilisers Derived from Bone and
other Organic Matter from that Derived from Rock Phosphate (pp. 491-498). Auchy, G.,
Sources of Error in Volhard's and Similar Methods of Determining Manganese in Steel
(pp. 498-511). Saarbach, L., A Simple Form of Gas Regulator (pp. 511-514). Linebarger ,
C. E., A Rapid Method of Determining the Molecular Masses of Liquids by Means of
their Surface Tensions (pp. 514-532). Delafontaine, AL, and Linebarger, C. E., On the
Reaction between Carbon Tetrachloride and the Oxidas of Niobium and Tantalum (pp.
532-536). Osborne, T. B., and Campbell, G. F., The Chemical Nature ot Diastase (pp.
536-542). Osborne, T. B., and Campbell, G. F., The Proteids of Malt (pp. 542-558).

Vol. xxi. No. 244. The Analyst. (July, 1896.)

Voelcker, J. A., and E. IV., Note on the Composition of Two Deposits formed in Water-pipes
(pp. 169-171). Mitchell, C. A., The Composition of Human Fat (pp. 171-174). Allen,
A. H., On the Composition and Analysis of Commercial Cream of Tartar (pp. 174-182).
Wiley, H. W., and Ewell, E. E., Determination of Lactose in Milks by Double Dilution
and Polarisation (pp. 182-186). Shepherd, H. H. B., Official Methods for the Analysis of
Fertilisers, issued by the German Manure Manufacturers' Association (pp. 186-191).

Vol. lxix. No. 403. Journal of the Chemical Society. (June, 1896.)

Play/air, Lord, Personal Reminiscences of Hofmann and of the conditions which led to the
establishment of the Royal College of Chemistry and his appointment as its Professor
(pp. 575-580). Abel, F. A., The History of the Royal College of Chemistry and Re-
miniscences of Hofmann' s Professorship (pp. 580-596J. Perkin, W. H., The Origin of
the Coal-Tar Colour Industry, and the Contributions of Hofmann and his Pupils (pp.
596-637). Armstrong, H. £., Notes on Hofmann's Scientific Work (pp. 637-733). JaPP<
F. R., and Lander, G. D., Condensation of Benzil with Ethylic Acetoacetate (pp. 736-
748). Walker, J., and Henderson, J., Electrolysis of Potassium Alloethylic Camphorate
(pp. 748-759). Dixon, H. B., Strange, E. H., and Graham, E., The Explosion of
Cyanogen (pp. 759-774). Dixon, H. B., The Mode of Formation of Carbonic Acid in
the Burning of Carbon Compounds (pp. 774-789). Dixon, H. B., and Harker, J. A., On
the Detonation of Chlorine Peroxide (pp. 789-792). Bablich, H., and Perkin, A. G.,
Morin. I. (pp. 792-799). Perkin, A. G., Luteolin. II. (pp. 799-804). Cross, C. F.,
Beran, E. J., and Smith, C, Constitution of the Cereal Celluloses (pp. 804-818). Purdie,
T., and Williamson, S., Ethereal Salts of Optically Active Malic and Lactic Acids (pp.
818-839). Dunsian, W. R., and Goulding, £., The Hydriodides of Hydroxylamine (pp.
839-842). Hartley, W. N., The Determination of the Composition of a "White Sou"
by a Method of Spectragraphic Analysis (pp. 842-844). Hartley, W. N., On the

F

xlviii SCIENCE PROGRESS.

Temperature of Certain Flames (pp. 844-848). Chattaway, F. D., and Evans, R. C. T.,
Metadichlorobenzine (pp. 848-851). Dixon, A. £., Halogen Additive Products of Sub-
stituted Thiosinnoamines (pp. 851-855). Dixon, A. £., Acidic Thiocarbimides, Thioureas,
and Ureas (pp. 855-869). Aymons, W. H., and Stephens, F. R., Carbon Dioxide: Its
Volumetric Determination (pp. 869-881).

Vol. xv. No. 6. Journal of the, Society of Chemical Industry. (30th June, 1896.)

Wall, E. J., Chromatic Photography (pp. 400-404). Gowland, W., Japanese Metallurgy:
I. Gold and Silver and their Alloys (pp. 404-414). Cowper-Coles, S., The Electro-
Deposition of Zinc (pp. 414-417). Coste, J. H., Notes on Laboratory Apparatus (pp.
417-418). Clowes, F., Acetylene: Limits of Explosibility of Mixtures with Air, and
Detection of Small Proportions in Air (pp. 418-419). Patoa, J. M. C, The Amount of
Air contained in Water (pp. 419-420). Barnes, J. , Titanium Oxide as a Mordant for
Wool, together with a Note on Zirconium and Cerium Oxides (pp. 420 422). Hummel,
J. /., and Brown, R. B., The Dyeing Properties of Catechin and Catechir-Tannic Acid
(pp. 422-426). Jeuks, R. L., The Hide-Powder Filter (pp. 426-427). Diusberg, C, The
Education of Chemists (pp. 427-432). Thompson, G. W., On the Analysis of White
Paints (pp. 432-434). Dewey, F. P. , Accuracy in Silver Assays (pp. 434-436). Waller,
£., Analysis of Chrome Ores (pp. 436-437).

Vol. xlii. No. 254. Philosophical Magazine and Journal of Science. (July, 1896.)

Witkowski, A. W. , Thermodynamic Properties of Air (pp. 1-37). Holman, S. W., Lawrence,
R. R., and Ban, L., Melting points of Aluminium, Silver, Gold, Copper, and Platinum
(pp. 37-52). Wilder mann, M., Note on the Degree of Dissociation of Electrolytes at O'
(pp. 102-103). Thompson, S. P., On Hyperphosphorescence (pp. 103-107).

Vol. lix. No. 357. Proceedings of the Royal Society. (18th June, 1896.)

Ramsay, W., Helium, a Gaseous Constituent of certain Minerals. II. Density (pp. 325-330).
Gamgee, A., On the Relations of Turacin and Turacoporphyrin to the Colouring Matter
of the Blood (pp. 339-342). Lockyer,/. N., On the New Gas obtained from Uraninite. VII.
Remarks on Messrs. Runge & Paschen's Diffusion Experiment (pp. 342-343).

Tome viii. Series 7. Annates de Chimie et de Physique. (July, 1896.)

Moissan, H., Recherches sur les differentes vari6t6s de carbone. I. Etude du carbone amorphe
(pp. 289-306). Moissan, H., Recherche sur les differentes vari^tds de carbone. II. Etude
du graphite (pp. 306-347). Cotton, A., Recherches sur l'absorption et la dispersion de la
lumiere par les milieux doutis du pouvoir rotatoire (pp. 347-432).

Tomes xv.-xvi. No. 12. Bulletin de la Societe Chimique de Paris. (20th June,

1896.)

Thomas, V. , Sur le bichlorure de bismuth (pp. 758-760). Thomas, V. , Action de l'air et du
peroxyde d'azote sur le bromure et iodure de bismuth (pp. 760-762). Fonzes-Diacon,
Action du bichlorure de mercure sur les alcools (pp. 762-763). Caseneuve, P., Sur un
nouveau mode de preparation de l'acide glycerique (pp. 763-764), Bertrand J., Sur
quelques ctitones de la serie grasse a poids moli^culaires elev<5s (pp. 764-768). Guinchant,
Nouveaux c!6riv£s des Others cyanacetiques (pp. 768-772). Klobb, T., Sur quelques acides
cyan^s nouveaux (pp. 773-778)- Grimaux, £., Note sur l'anethol (pp. 778-779).
J'r/id'hommc, M. , Propritites des fuchsines ; leur oxydation par le peroxyde de plomb
(pp. 780-783), Bidtrtx, A., Action de la phenylhydrazine sur l'acide gallique et sur
l'acide dibromogallique (pp. 783-786). Quiroga, A., Argine. Arginine (pp. 787-791).
Bertrand, G. , Sur les rapports qui existent entre la constitution chimique des composes
organiques et leur oxydabilite sous l'influence de la laccase (pp. 791-793). Be?-lrand, G.,
Sur une nouvelle oxydase ou ferment soluble oxydant, d'origine v£gt:tale (pp. 793-797).
Mot eigne, H., Sur un nouveau corps (raphanol) retird de la racine de raphanus niger ou
radis noir (cruciferes) et de quelques autres plantes de la meme famille. — Considerations
sur l'essence de raphanus niger (pp. 797-803). Revitre, G., et Bailhache, G., Etude du
proctide' Kjeldahl et modifications a y apporter (pp. 806-811). Petit, A., et Terrat, P.,
Sur le dosage de la cafeine dans le the (pp. 811-115).

ENUMERATION OF TITLES. xlix

Tomes xv.-xvi. No. 13. (5th July, i8g6.)
Ferreira da Silva, A. J., Sur la constitution des Carbonyles metalliques (pp. 835-838).
Tommasi, D., Precede eiectrolytique pour 1' extraction, la separation et l'affinage des
metaux (pp. 838-842). Causse, H., Surles aldehydates de phenylhydrazine (pp. 842-846).
Patein, G., et Dufau. E. , Des combinaisons de l'antipyrine avec les acides oxybenzoiques
et leurs derives (pp. 846-850). H'ebert, A., et Truffaut, G., Etude physiologique des
cyclamens (1) (pp. 850-855). Aglot, Dosage optique de l'acide sulfurique (pp. 855-862).
Deniges, G. , Methode generate pour le dosage du mercure sous une forme quelconque
(pp. 862-871).

Tome cxxiii. No. 23. Comptes Rendus hebdomadaires de V Academic des Sciences.

(8th June, 1896.)

Moissan, H., Etude de la fonte et du carbure de vanadium (pp. 1297-1302). Moissait, H.,
Sur une nouvelle methode de preparation des alliages d'aluminium (pp. 1302-1303).
Chauveau, A., Sur la nature du processus chimique qui preside a la transformation du
potentiel auquel les muscles empruntent l'energie necessaire a leur mise en travail (pp.
1303-1309). Boltzmann, Sur la theorie des gaz (pp. 1314). Raoul, F. M., Influence de
la temperature du refrigerant sur les mesures cryoscopiques (pp. 1315-1319). De Gram-
mont, A., Sur les spectres des metalloides dans les sels fondus. Soufre (pp. 1326-1328).
Fabre, C., Sur le dosage de la potasse (pp. 1331-1333). Marshall, D., Sur la chaleur de
vaporisation de l'acide formique (pp. 1333-1335). Patein, G., et Dufau, Combinaisons de
l'antipyrine avec les acides oxybenzoiques et leurs derives (pp. 1335-1338). TrouvS, G.,
Sur l'eclairage a l'acetylene (pp. 1338-1342). Griffiths, A. B., Sur la composition du
pigment rouge d'Amanita muscaria (pp. 1342-1343).

Tome cxxii. No. 24. (15th June, 1896.)

Carnot, A., Sur les variations observees dans la composition des apatites (pp. 1375-1380).
Sabatier, P. , Sur une reaction des composes cuivreux pouvant servir a caracteriser les
azotites (pp. 1417-1419). Hallopeau, L. A., Sur les combinaisons zirconotungstiques (pp.
1419-1422). Barbie?; P. , et Bouveault, L. , Synthese de la methylheptenone naturelle (pp.
1422-1424).

Tome cxxii. No. 25. (22nd June, 1896.)

Moissan, H., Sur la formation des carbures d'hydrogene gazeux et liquides par l'action de l'eau
sur les carbures metalliques. Classification des carbures (pp. 1462-1467). Sabatier, P.,
Sur l'acide nitrosodisulfonique bleu fonce (pp. 1479-1482). Combes, C, Sur la preparation
des alliages d'aluminium par voie de reaction chimique (pp. 1482-1484). Granger, A.,
Sur l'action du phosphore sur quelques chlorures metalliques (pp. 1484-1486). Cavalier,
/., Mesure d'une chaleur d'etherification par l'action du chlorure d'acide sur l'alcool sode
(pp. 1486-1488). Rivals, P., Sur l'acetal et Facdtal monochlore (pp. 1488-1489).
Rivals, P., Sur les ethers ethyliques des acides acetiques chlores (pp. 1489-1491). Bou-
veault, L., Action de 1' hydrazine sur les acides glyoxyliques de la sede aromatique (pp.
1491-1493). Guerbet et Belial, A., Sur la constitution de l'acide camphoienique inactif
(pp. 1493-1496). Balland, Sur la valeur nutritive des farines et sur les consequences
economiques d'un blutage exagere (pp. 1496-1499). Bach, A., Sur le mecanisme chimique
de la reduction des azotates et de la formation de matieres azotees quartenaires dans les
plantes (pp. 1499-1502). Jacquemin, G., Denaturation rationnelle de l'alcool (pp. 1502-

1503)-

Tome cxxii. No. 26. (29th June, 1896.)
De Gramont, A., Sur le spectre du phosphore dans les sels fondus et dans certains produits
metallurgiques (pp. 1534-1537)- Sabatier, P. , Sur l'acide nitrosodisulfonique bleu et sur
quelques-uns de ses sels (pp. 1537-1539)- Thomas, V., Action de l'iode sur le chlorure
stanneux (pp. 1539-1541). Aloy, J., Recherches thermiques sur les composeesdel'uranium
(pp. 1541-1543). Bouveault, L., Nouvelle methode pour la preparation d'aldehydes aro-
matiques(pp. 1543-1545)- Bietrix, A., Recherches sur la chloruration de l'acide gallique.
Formation d'acide dichlorgallique et de trichloropyrogallol (pp. 1545-1548). Minguin,
Proprietes cristallographiques des benzylidene, methyl- et ethyl-salicidenes, et anisal cam-
phres (pp. 1548-1550). H'ebert, A., Sur un nouvel acide gras non sature, l'acide isanique
(pp. 1550-1553).

l SCIENCE PROGRESS.

i6e Annee. Tome iii. No. 12. Journal de Pharmacic et de Chimie.

(15th June, 1896.)

Bonrquelot, E., Sur la presence dans le Monotropa hypopytis d'un glucoside de l'ether
methylsalicylique et sur le ferment soluble hydrolysant de ce glucoside (pp. 577-582).
Causse, H., Sur le tartrate de phenylhydrazine et ses derives (pp. 582-589). Georges, Sur
le chlorhydrosulfate de quinine (pp. 589-594). Matrot, A., Dispositif pour maintenir la
Constance du niveau d'un liquide dans un recipient (pp. 594-595). Cazeneuve, Sur un
caractere distinctif de la fuchsine ordinaire et de la fuschine acide. S. Sur la reaction de
Schiff(pp. 595-597).

i6e Annee. Tome iv. No. 1. (1st July, 1896.)

Thibault, P., Etude sur le dosage polarimetrique du lactose contenu dans le lait de femme
(pp. 5-10). Moreigne, H., Sur un nouveau corps (Raphanol) retire de la racine de
Raphanus niger du radis noir (cruciferes) et de quelques autres plantes de la meme famille.
Considerations sur l'essence de Raphanus niger (pp. 10-16). Cazeneuve, P., Sur un
nouveau mode de preparation de l'acide glycerique (pp. 16-18). Linde/, L., Caracterisa-
tion et separation des principaux acicles contenus dans les vegetaux (pp. 18-21). Planchon,
L., Le commerce actuel de l'hcrboristerie dans une region du Languedoc (pp. 21-25).

Tome xxviii. No. 4. Journal de la Societe Physico-Chimique Russe.

Speransky, A., Sur le rhodanure de chrome (pp. 329-335). Zelinsky, N., et Tchernosvitoff, N.,
Sur les acides dimethyltricarballyliques stereoisomers (pp. 335-345). Tchernik, G., Sur
un mineral ceritique du district de Batoum (345-360). Barilovitch, A., Synthese et
proprietes de l'acide dimethyloxypelargonique (pp. 360-365). Rabinmitch, J., Analyse de
l'eau du lac sale" de Golopristan (pp. 365-371). Petrenko-Kritchenko, P., et Stanichevsky,
/., Sur la condensation des aldehydes et des ethers acetondicarboniques (pp. 371-374).
Tanatar, S., Sur l'acide hypoazotique libre (pp. 374-376). Tanatar, S., Sur la formation
de la soude naturelle (pp. 376-384). Antipoff, J., Sur les pyrites contenant du thallium
(pp. 384-388). Wagner, E., Ertchikovsky, G., et Gbisberg, A., Sur la structure des
terpenes ; Worms, W., Sur les methodes de l'acidimetrie ; Worobieff, N. , Sur les hydrates
de sulphate de cadmium et de chlorate de cadmium ; Lubarsky, E. , Sur le hydrate de
l'aluminium chlorate, contenant neuf molecules d'eau ; Lubarsky, E. , Sur les hydrates des
sels halogeniques du Zink ; Lubarsky, £., Sur les hydrates de bromure et iodure de
calcium, contenant six molecules d'eau; Tanatar, S., Sur la decomposition de l'hydroxy-
lamene fumarique ; Giliaroff, A., Sur le synthese de l'acide trimethylethylenelactique.
Ginsbetg, A., Sur un appareil perfectionne pour la distillation sous pressiodn iminuee
(pp. 388-398).

Band ccxxxiv. Heft 5. Archiv der Pharmacic (24th June, 1896.)

Gildemeister, £., und Stephan, R., Ueber Palmarosaol (pp. 321-330). Kassner, G., Beitrag
zur Kenntniss der Ferricyansalze und ihrer Anwendung als Oxydationsmittel (pp. 330-348).
Schaer, E., Ueber die Einwirkung des Morphiums sowie des Acetanilids auf Mischungen
von Ferrisalz und Kaliumferricyanid (pp. 348-367). Pommereh?ie, E., Ueber die Einwir-
kung von Jodmethyl auf Xanthinsalze (pp. 367-380). Toppelius, H., und Pommerehne,
E. , Ueber Kreatinine verschiedenen Usprungs (pp. 380-397). Hoehnel, M. , Zur Kenntniss
der Metaplumbate (pp. 397-400).

Jahrgang xxix. No. 10. Berkhte der Deutschen Chemischen Gesellschaft.

(22nd June, 1896.)

Weil, H., Die Constitution der Farbbasen der Triphenylmethanreihe (pp. 1541-1543).
Auwers, K., und v. Campenhausen, F. G., Ueber Oxytrimethylbernsteinsaure (pp.
IS43-iS49)- Emmerling, O., Untersuchung einer Emaille (pp. 1 549-1550). Scholl, R.,
und Matthaiopoulos, G. , Zur Kenntniss der a- Halogenketoxenie (pp. 1550-1559). Piloty,
O., Ueber eine Oxydation des Hydroxylamins durch Benzolsulfochlina (pp. 1559-1567).
Willgerodt, C, Rationelle Darstellungsweisen von Jodoverbindungen (pp. 1 567-1575).
Willstdlter, R., Zur Kenntniss von Tropinin und Nontropinin. III. (pp. 1575-1585).
Heidenreich, M., Quantitative Analyse durch Elektrolyse (pp. 1585-1590). Einhorn, A.,

ENUMERATION OF TITLES. li

Ueber die Reduction der Benzylamincarbonsauren (pp. 1590-1595). Wallach, O., Ueber
Condensationsproducte cyclisher Ketone und Synthesen innevhalb der Terpengruppe
(pp. 1595-1602). Fischer, O., und Disc/linger, A., Ueber die Oxydationsproducte des
Orthoamidodiphenylamins (pp. 1602-1609). Fried lander. P., und Riidt, H., Unter-
suchungen ueber isomere Naphtalinderivate. III. (pp. 1609-1613).

Band liii. Nos. 8, 9. Journal fur praktische Chemie. (9th May, 1896.)

Stohmann, F. , und Schmidt, R., Ueber den Warmewerth der Hippursaure, ihrer Homologen
und der Anisursaure (pp. 345-369). Schickler, P., Zur Kenntniss eines neuen Kohlen-
wasserstoffes C14H12 (pp. 369-375). Edinger, A., Zur Kenntniss des Jodisochinolins und
der beiden isomeren Jod- o- Phtalsauren (pp. 375-390). Clans, A., und Setzer, E., Zur
Kenntniss des ana- Nitro- und des o- Amido- Chinolins (pp. 390-414). Busch, M., Zur
Kenntniss des o- Amidobenzylamine. III. (pp. 414-427). Walter, J., Beitrag zur Erk-
larung der Sandmeyerischen Reaction (pp. 427-431). Ponzio, G., Einwirkung von Sal-
petersaure auf aliphatische Aldehyde (pp. 431-432).

Band liii. Nos. 10, 11. (9th June, 1896.)

Walther, R., Ueber Reduktion mittelst Phenylhydragins (pp. 433-472). Walther, R., Ueber
die Einwirkung von Orthoamei'senather auf primare aromatische Amine (pp. 472-478).
Troeger, J., und Eggert, A., Ueber die Einwirkung von Thiophenol auf Diketone der
aromatischen Reihe (pp. 478-484). Troeger, /., und Artmann, K., Ueber ungesaltigte
Sulfone der Naphtalivreihe (pp. 484-501). Stoehr, C, und Branetes, P., Synthese von
Trimethylpyrazin und Tetramethylpyrazin (pp. 501-512).

Band xvii. Heft 3. Monatsheftc fiir Chemie und verwandte Theile anderer
Wissenschaften. (30th May, 1896.)

Braun, L., Ueber die Einwirkung von Isobutyraldehyd auf Malon- und Cyanessig-Saure (pp.
207-225). Gregor, G., Zur Constitution der Monoathyl-j8-Resorcylsaure (pp. 225-229).
Heilpem, J., Ueber das sogenannte Carbothiacetonin (pp. 229-245). Wegscheider, R.,
Ueber das Phenylhydrazin undOxim des Proto-catechu-Aldehyds (pp. 245-253). Brunner,
K., Eine Indoliumbase und ihr Indolinon (pp. 253-281).

Jahrgang xxxv. Heft 3. Zeitschrift fiir Analytische Chemie. (20th May, 1896.)

Beckmann, E., Beitrage zur Priifung des Honigs (pp. 263-285). Schjerning, H., Noch einige
Bemerkungen ueber die quantitative Trennung der in Bierwuirze vorhandenen Proteinstoffe
(pp. 285-297). Kolk, J. L. C. S., Doppelverbindungen von Anilin mit Metallsalzen. I.
(pp. 297-305). Riegler, £., Eine neue Bestimmungs-methode der loslichen Jodverbin-
dungen auf titrimetrischem Wege (pp. 305-308). Riegler, £., Zur Literstellung der
Thiosulfatlosung mittelst Jodsaure (pp. 308-309). Vedrodi, V., Zur Bestimmung des
Nicotinsund des Ammoniaks im Tabak (pp. 309-311). Ritter, G. v., Ueber die quanti-
tative Bestimmung des Zinks in organischen Salzen (pp. 311-314). Aufschldger, H.,
Ueber das Verhalten stickstofthaltiger organischer Korper gegen Mehrfachschwefelkalium
bei Loherer Temperatur (pp. 314-318). Leceo, M. T., Ueber das Vorkommen von Jod im
Wasser (pp. 318-322). Belar, A., Prufiing der Rothweine auf fremde Farbstoffe (pp. 322-
324). Dierbach, K., Ein neuer Bunsen-Brenner (pp. 324-325). Frexnius, H., und
Makin, C. J. L., Ueber die Bestimmung des Phenols in Seisen und Desinfectionsmetheln
(pp. 32S-334)-

Band xxii. Heft 1. Zeitschrift ficr Physiologische Chemie. (16th May, 1896.)

Baumann, £., Ueber den Jodgehalt der Schilddriisen von Menschen und Thieren. III. (pp.
1-16). Roos, E., Ueber die Wirkung des Thyrojodins (pp. 16-62). Nultall, G. H. F.,
und Theerf elder, H., Thierisches Leben ohne Bakterien in Verdauumgskanal. II. (pp.
62-74). Kossel, A., und Neumann, A., Ueber Nuclei'nsaure und Thyminsaure (pp.
74-82). Schulze, £., Ueber das Vorkommen von Nitraten in Keimpflangen (pp. 82-90).
Sckulze, £., und Winterstein, E., Ueber einen phosphorhaltigen Bestandtheil der
Pflangensamen (pp. 90-95). Kriiger, T. R., Ueber die Abspaltung von Koblensaure aus
Phosphorfleischsaure durch Hydrolyse (pp. 95-102).

Lii SCIENCE PROGRESS.

Anno xxvi. Vol. i. Fascicolo 5 e 6. Gazzetta Chimica Italiana.

(28th June, 1896.)

Oddo, G., e Leonatdi, G., Sul mononitrite dell' acido canforico e le trasposizioni atomiche dell'
isonitrosocanfora (pp. 405-423). Ponzio, G., Azione dell' acido nitrico sulle aldeidi
alifatische (pp. 423-425). Tarugi, N., Sull' amalgama di platino e sua applicazione nella
chimica analitica (pp. 425-431). Piutti, A., e Giustiniani, E., Sui derivati maleinici di
alcune ammine grasse (pp. 431-441). Minunni, G., e Pap, £., Ricerche sui prodotti di
ossidazione degli idrazoni. I. Ossidazione del benzalfenilidrazone (pp. 441-456. Minunni,
G., e Vassallo, D., Nuove ricerche sulla trasformazione delle a- aldossime in nitriti (pp.
456-466). Bartoli, A., II coefficiente di compressibiliia degli idrocarburi Cn H2n + 2 (pp.
466-472). Bartoli, A., e Stracciati, E., Sul calore specifico a volume costante degli idro-
carburi Cn H2n +2 dei petroli di Pensilrania (pp. 472-475). Bartoli, A., Sulla scelta dell'
unita di calore (pp. 475-483). Carrara, G., e Zopptllari, /., Velocita di reazione in
sistemi non omogenei. II. Scomposizione coll' acqua di alcune combinazione dello zolfo e
del fosforo (pp. 483-494). Vianello, M. A7., Sulla velocita di formazione dei xantogenati
alcalini (pp. 494-501).

Price HALF-A-OROWN.
Subscription Price, TWENTY-FIVE SHILLINGS per Annum, Post Free.

VOL. V.

No. 25.

ctence

repress

A MONTHLY REVIEW OF CURRENT SCIENTIFIC INVESTIGATION.

Conducted by HENRY C. BURDETT.

Edited by J. BRETLAND FARMER, M.A.

WITH THE CO-OPERATION OF THE FOLLOWING EDITORIAL COMMITTEE: —

H. E. ARMSTRONG, F.R.S., Professor of Chemistry at the City and Guilds of London Institute for Technical
Education.

W. R. DUNSTAN, F.R.S., Professor of Chemistry, St. Thomas' Hospital and Pharmaceutical Society,
London.

G. F. FITZGERALD, F.R.S., Professor of Natural and Experimental Philosophy in the University of Dublin.

C. S. SHERRINGTON, F.R.S., Professor of Physiology in University College, Liverpool.

J. W. JUDD, C.B., F.R.S., Dean of the Royal College of Science, London.

W. J. SOLLAS, F.R.S., Professor of Geology in the University of Dublin.

G. B. HOWES, F.Z.S., Professor of Zoology, Royal College of Science, London.

H. MARSHALL WARD, F.R.S., Professor of Botany in the University of Cambridge.

MARCH, 1896.

CONTENTS.

LUDWIG AND MODERN PHYSIOLOGY. By J. BURDON SANDERSON, M.D.,
F.R.S., Regius Professor of Medicine in the University of Oxford

ON RECENT ADVANCES IN VEGETABLE CYTOLOGY. By J. BRETLAND

FARMER, M.A., Professor of Botany in the Royal College of Science, London ...

THE MORPHOLOGY OF THE MOLLUSCA.

Lincoln College, Oxford

By W. GARSTANG, M.A., Fellow of

THE RESERVE MATERIALS OF PLANTS (Concluded). By J. REYNOLDS GREEN,
M. A. , F.R.S., Professor of Botany to the Pharmaceutical Society, London

AFRICAN GRASS FIRES AND THEIR EFFECTS. By G. F. SCOTT ELLIOT, M.A.

APPENDICES :

I. NOTICES OF BOOKS

II. CHEMICAL LITERATURE FOR JANUARY, 1896

22

38

60
77

1

IV

THE SCIENTIFIC PRESS, LIMITED, 428 Strand, W.C.

NEW YORK, BOSTON AND CHICAGO (Special American

Edition) : Messrs. D. C. HEATH & CO.
DUBLIN : Messrs. FANNIN & CO., 41 GRAFTON ST.
EDINBURGH AND GLASGOW: Messrs. JOHN

MENZIES & CO.
TORONTO: THE TORONTO NEWS CO.
MONTREAL: THE MONTREAL NEWS CO.

BERLIN: Messrs. A. ASHER & CO.
PARIS: LIBRAIRIE GALIGNANI, 224 RUE RIVOLI.
INDIA: Messrs. THACKER AND CO.
MELBOURNE, SYDNEY, ) Messrs. GORDON

ADELAIDE, NEW ZEALAND: I AND GOTCH.

SOUTH AFRICA: Messrs. JUTA, CAPE TOWN.
LEIPZIG: Mr. ALFRED LORENTZ.

USEFUL BOOKS FOR THE GARDEN.

THE ENGLISH FLOWEE GARDEN. Style, position, and arrange-
ment. With a description of all the best plants for it, their culture and
arrangement. A New Edition of this hook will shortly he published. The
text has been thoroughly revised and in great part rewritten ; and many new
and beautiful woodcuts, both in addition to, and in place of, those which have
already appeared, will be given. By Wm. Robinson. Medium 8vo, 15s. ; post
free, 15s. 6d.

THE VEGETABLE GARDEN. Illustrations, Descriptions, and
Culture of the Garden Vegetables of cold and temperate climates. By MM.
Vilmorin-Andrieux of Paris. English Edition. Just published. 8vo. Illus-
trated, 15s. ; post free, 15s. 6d.

A DICTIONARY OF ENGLISH NAMES OF PLANTS " applied

in England and among English-speaking People to Cultivated and Wild Plants,
Trees and Shrubs". In two Parts — English-Latin and Latin-English. By Wm.
Miller. 12s. ; post free, 12s. 6d. "A work of value which extends over a large
field, including cultivated native and foreign plants, trees and shrubs." — Times,
25th July, 1885.

GREENHOUSE AND STOVE PLANTS, Floweeing and Fine-
Leaved Palms, Ferns, and Lycopodidms, with full details of the propagation
and cultivation of 50 families of plants, embracing all the best kinds in cultivation
suitable for growing in the greenhouse, intermediate house and stove. By
Thomas Baines. Price 8s. 6d. ; post free, 9s.

HARDY FLOWERS. Giving descriptions of upwards of 1300 of the
most ornamental species, with directions for their arrangement, culture, etc. Fifth
and Popular Edition. Price Is. ; post free, Is. 3d.

THE SUBTROPICAL GARDEN; or, Beauty of Form in the

Flower Garden ; with Illustrations of the finer foliage plants used for this pur-
pose. By Wm. Robinson. 5s. ; post free, 5s. 6d.

GARDEN DESIGN AND ARCHITECTS' GARDENS. Two Re-
views, Illustrated, to show by actual Examples from British Gardens, that clipping
and aligning trees to make them " harmonise " with architecture is barbarous, need-
less and inartistic. By W. Robinson, F.L.S. Demy 8vo, 5s. From John Murray,
Albemarle Street, London.

THE GARDEN ANNUAL, ALMANACK, AND ADDRESS BOOK,

FOR 1896. Containing an Almanack for the year 1896. Seasonable work for each
Month. Flowers, fruits, and vegetables procurable each Month. New plants of the
past year. Alphabetical List of Nurserymen, Seedsmen, and Florists. List of
Horticultural Builders, etc., etc. Lists of Gardens, Country Seats, and Gardeners.
Price Is. ; post free, Is. 3d.

Weekly, 3d. ; Post Free, 3id. Monthly Parts, Is. ; Post Free, Is. 3d. Annual Subscription, 17s. 6d.

THE GARDEN:

An Illustrated Journal of Horticulture in all its Branches.

coloured plates, faithfully drawn, of new or rare plants, are issued with

each number.

Weekly, Id. Monthly Parts, 5d. Yearly Subscription, 6s. 6d.

Illustrated. For Town and Country.

The Paper for Amateur and Villa Gardeners, Suburban, Cottage, and Town
Gardening. Window Plants, Bees, Poultry, etc.

THE GARDEN OFFICE, 37 Southampton Street, Strand, London, Ull

SCIENCE.

A Weekly Journal devoted to the Advancement

of Science.

Editorial Committee: S. Newcomb, Mathematics ; R. S. Woodward, Mechanics;
E. C. Pickering, Astronomy ; T. C. Mendenhall, Physics; R. H. Thurston,
Engineering; Ira Remsen, Chemistry; Joseph Le Conte, Geology; W. M.
Davis, Physiography; O. C. Marsh, Paleontology; W. K. Brooks, Inverte-
brate Zoology ; S. H. Scudder, Entomology ; C. Hart Merriam, Vertebrate
Zoology; N. L. Britton, Botany; Henry F. Osborn, General Biology; H.
P. Bowditch, Physiology; J. S. Billincs, Hygiene; J. McKeen Cattell,
Psychology ; Daniel G. Brinton, J. W. Powell, Anthropology.

SCIENCE holds the position in America that is held
by Nature in England. It reports on the progress of
science with special reference to the most recent work
of American men of science. Science is making rapid
progress in America in all directions, and in some of its
departments is in advance of any other country. A know-
ledge of the work being accomplished is essential to all
who wish to follow the progress of science, and this can
be most conveniently and adequately secured with the aid
of this journal. We believe that it is almost necessary for
men of science in Europe either to subscribe to SCIENCE
or provide for its presence in an accessible library.

Annual Subscription, £1 Os. 6dm Single Conies, 8dm

Address:— SCIENCE, 41 East 49th Street, New York.

For Insuring in the

JVtutual kife lr)surat)cc
Con?par;y of flew York

(RICHARD A. McCURDY, President).
It is financially strong.

Assets - - - Dec, 31st, 1894 - £42,020,284
Liabilities - „ - £37,394,739

Surplus - „ - £4,626,145

It is purely Mutual.

There are no Shareholders to make a profit out of the Policy-holders, who receive
all the many benefits that come from entering an Institution of the highest standing,
whose position has been made by the co-operation of two generations of Policy-holders
and officials.

Its past record is magnificent.

It has received from its Policy-holders - - £107 , 225, 776

It has paid to its Policy-holders - - £79,802,067

And besides holding the balance of - - £27, 333,709

It has earned for its Policy-holders - - £14,556,500

Thus it now holds for its Policy-holders - - £41 ,890, 209

Its present position is splendid.

The Insurance Department of the State of New York recently completed a thorough
examination of the Company, and the Report of the State Superintendent, dated 17th
July, 1895, certifies: —

" That the company is solvent and strong and is conducted in all respects in accordance with law
and sound business principles. It merits, in all respects, the confidence of the insured and the
community at large."

Its future is certain.

" That which they have done but earnest of the things that they shall do." — Tennyson.
Insurance is a provision for the future, and it is above all things necessary to entrust
that future to an Institution too well founded, too great to be damaged or destroyed by
any of the vicissitudes of an unknown future.

Its Policies meet all needs.

The Company issues many kinds of policies and by means of them provides for
every contingency that can be reasonably looked for.

Apply for particulars to any of the Branches or to

Head Office forthe United Kingdom : 17 & 18 CORNHILL, LONDON, E.C.

D. C. HALDEMAN, General Manager.

Price HALF-A-CROWN.
Subscription Price, TWENTY-FIVE SHILLINGS per Annum, Post Free.

VOL. V.

No. 26.

Science

A MONTHLY REVIEW OF CURRENT SCIENTIFIC INVESTIGATION.

Conducted by HENRY C. BURDETT.

Edited by J. BRETLAND FARMER, M.A.

WITH THE CO-OPERATION OF THE FOLLOWING EDITORIAL COMMITTEE:—

H. E. ARMSTRONG, F.R.S., Professor of Chemistry at the City and Guilds of London Institute for Technical

Education.
W. R. DUNSTAN, F.R.S., Professor of Chemistry, St. Thomas' Hospital and Pharmaceutical Society,

London.
Q. F. FITZGERALD, F.R.S., Professor of Natural and Experimental Philosophy in the University of Dublin.
C. S. SHERRINGTON, F.R.S., Professor of Physiology in University College, Liverpool.
J. W. JUDD, C.B., F.R.S., Dean of the Royal College of Science, London.
W. J. SOLLAS, F.R.S., Professor of Geology in the University of Dublin.
G. B. HOWES, F.Z.S., Professor of Zoology, Royal College of Science, London.
H. MARSHALL WARD, F.R.S., Professor of Botany in the University of Cambridge.

APRIL, 1896.

CONTENTS.

THE GENERAL BEARINGS OF MAGNETIC OBSERVATIONS. By Captain
ETTRICK W. CREAK, R.N., F.R.S., Superintendent of Compasses at the Admiralty

THE PRESENT POSITION OF CELL-THEORY (Part I.). By G. C. BOURNE, M.A.,
Fellow of New College, Oxford ... ...' ... ... ...

SOLID SOLUTIONS. By JAMES WALKER, Ph.D., D.Sc, Professor of Chemistry .in
University College, Dundee

THE STELAR THEORY : a History and a Criticism (Part I.). By A. G. TANSLEY, B.A.

ON SOME APPLICATIONS OF THE THEORY OF OSMOTIC PRESSURES TO
PHYSIOLOGICAL PROBLEMS (Part II.). By E. H. STARLING, M.D., Lecturer on
Physiology at Guy's Hospital, London

APPENDICES:

I. NOTICES OF BOOKS

II. CHEMICAL LITERATURE FOR FEBRUARY, 1896

81

94

121
*33

151

XI
XV

THE SCIENTIFIC PRESS, LIMITED, 428 Strand, W.C.

NEW YORK, BOSTON AND CHICAGO (Special American

Edition) : Messrs. D. C. HEATH & CO.
DUBLIN : Messrs. FANNIN & CO., 41 GRAFTON ST.
EDINBURGH: Messrs. OLIVER & BOYD.
GLASGOW: Messrs. JOHN MENZIES & CO.
TORONTO: THE TORONTO NEWS CO.
MONTREAL: THE MONTREAL NEWS CO.

BERLIN: Messrs. A. ASHER & CO.
PARIS: LIBRAIRIE GALIGNANI, 224 RUE RIVOLI.
INDIA: Messrs. THACKER AND CO.
MELBOURNE, SYDNEY, ) Messrs. GORDON

ADELAIDE, NEW ZEALAND:) AND GOTCH.

SOUTH AFRICA: Messrs. JUTA, CAPE TOWN.
LEIPZIG: Mr. ALFRED LORENTZ.

USEFUL BOOKS FOR THE GARDEN.

THE ENGLISH FLOWEE GARDEN. Style, position, and arrange-
ment. With a description of all the best plants for it, their culture and
arrangement. A New Edition of this book will shortly be published. The
text has been thoroughly revised and in great part rewritten ; and many new
and beautiful woodcuts, both in addition to, and in place of, those which have
already appeared, will be given. By Wm. Robinson. Medium 8vo, 15s. ; post
free, 15s. 6d.

THE VEGETABLE GARDEN. Illustrations, Descriptions, and
Culture of the Garden Vegetables of cold and temperate climates. By MM.
Vilmorin-Andrieux of Paris. English Edition. Just published. 8vo. Illus-
trated, 15s. ; post free, 15s. 6d.

A DICTIONARY OF ENGLISH NAMES OF PLANTS "applied

in England and among English-speaking People to Cultivated and Wild Plants,
Trees and Shrubs". In two Parts — English-Latin and Latin-English. By Wm.
Miller. 12s. ; post free, 12s. 6d. "A work of value which extends over a large
field, including cultivated native and foreign plants, trees and shrubs." — Times,
25th July, 1885.

GREENHOUSE AND STOVE PLANTS, Floweeing and Fine-
Leaved Palms, Ferns, and Lycopodiums, with full details of the propagation
and cultivation of 50 families of plants, embracing all the best kinds in cultivation
suitable for growing in the greenhouse, intermediate house and stove. By
Thomas Baines. Price 8s. 6d. ; post free, 9s.

HARDY FLOWERS. Giving descriptions of upwards of 1300 of the

most ornamental species, with directions for their arrangement, culture, etc. Fifth
and Popular Edition. Price Is. ; post free, Is. 3d.

THE SUBTROPICAL GARDEN; ok, Beauty of Form in the

Flower Garden ; with Illustrations of the finer foliage plants used for this pur-
pose. By Wm. Kobinson. 5s. ; post free, 5s. 6d.

GARDEN DESIGN AND ARCHITECTS' GARDENS. Two Re-
views, Illustrated, to show by actual Examples from British Gardens, that clipping
and aligning trees to make them "harmonise" with architecture is barbarous, need-
less and inartistic. By W. Robinson, F.L.S. Demy 8vo, 5s. From John Murray,
Albemarle Street, London.

THE GARDEN ANNUAL, ALMANACK, AND ADDRESS BOOK,

FOR 1896. Containing an Almanack for the year 1896. Seasonable work for each
Month. Flowers, fruits, and vegetables procurable each Month. New plants of the
past year. Alphabetical List of Nurserymen, Seedsmen, and Florists. List of
Horticultural Builders, etc., etc. Lists of Gardens, Country Seats, and Gardeners.
Price Is. ; post free, Is. 3d.

Weekly, 3d. ; Post Free, 3id. Monthly Parts, Is. ; Post Free, Is. 3d. Annual Subscription, 17s. 6d.

THE GARDEN:

An Illustrated Journal of Horticulture in all its Branches.

COLOURED PLATES, FAITHFULLY DRAWN, OF NEW OR RARE PLANTS, ARE ISSUED WITH

EACH NUMBER.

Weekly, Id. Monthly Parts, 5d. Yearly Subscription, 6s. 6d.

Illustrated. For Town and Country.

The Paper for Amateur and Villa Gardeners, Suburban, Cottage, and Town
Gardening. Window Plants, Bees, Poultry, etc.

TfiE GjHiDEN OFFIGE, 37 Soiiifiampion Street Sirend, London, N.G.

SCIENCE.

A Weekly Journal devoted to the Advancement

of Science.

Editorial Committee : S. Newcomb, Mathematics; R. S. Woodward, Mechanics;
E. C. Pickering, Astronomy ; T. C. Mendenhall, Physics; R. H. Thurston,
Engineering; Ira Remsen, Chemistry; Joseph Le Conte, Geology; W. M.
Davis, Physiography; O. C Marsh, Paleontology; W. K. Brooks, Inverte-
brate Zoology; S. H. Scudder, Entomology; C. Hart Merriam, Vertebrate
Zoology; N. L. Britton, Botany; Henry F. Osborn, General Biology; H.
P. Bowditch, Physiology; J. S. Billincs, Hygiene; J. McKeen Cattell,
Psychology ; Daniel G. Brinton, J. W. Powell, Anthropology.

SCIENCE holds the position in America that is held
by Nature in England. It reports on the progress of
science with special reference to the most recent work
of American men of science. Science is making rapid
progress in America in all directions, and in some of its
departments is in advance of any other country. A know-
ledge of the work being accomplished is essential to all
who wish to follow the progress of science, and this can
be most conveniently and adequately secured with the aid
of this journal. We believe that it is almost necessary for
men of science in Europe either to subscribe to SCIENCE
or provide for its presence in an accessible library.

Annual Subscription, £1 Os. 6dm Single Copies, 8d.

Address :— SCIENCE, 41 East 49th Street, New York.

For Insuring in the

JVtutual Mfe ft^sura^ce
Cot^pa^y of flew York

(RICHARD A. McCURDY, President).
It is fina.ncia.liy strong.

Assets - - - Dec, 31st, 1894 - £42,020,284
Liabilities - „ - £37,394,139

Surplus - „ - £4,626,145

It is purely Mutual.

There are no Shareholders to make a profit out of the Policy-holders, who receive
all the many benefits that come from entering an Institution of the highest standing,
whose position has been made by the co-operation of two generations of Policy-holders
and officials.

Its past record is magnificent.

It has received from its Policy-holders - - £107 , 225, 776

It has paid to its Policy-holders £79,892,067

And besides holding the balance of £27 , 333, 709

It has earned for its Policy-holders - - £14,556,500

Thus it now holds for its Policy-holders - £41 ,890,209

Its present position is splendid.

The Insurance Department of the State of New York recently completed a thorough

examination of the Company, and the Report of the State Superintendent, dated 17th

July, 1895, certifies: —

" That the company is solvent and strong and is conducted in all respects in accordance with law
and sound business principles. It merits, in all respects, the confidence of the insured and the
community at large."

Its future is certain.

" That which they have done but earnest of the things that they shall do." — Tennyson.
Insurance is a provision for the future, and it is above all things necessary to entrust
that future to an Institution too well founded, too great to be damaged or destroyed by
any of the vicissitudes of an unknown future.

Its Policies meet all needs.

The Company issues many kinds of policies and by means of them provides for
every contingency that can be reasonably looked for.

Apply for particulars to any of the Branches or to

Head Office for the United Kingdom : 17 & 18 CORNHILL, LONDON, E.C.

D. C. HALDEMAN, General Manager.

Price HALF-A-CROWN.
Subscription Price, TWENTY-FIVE SHILLINGS per Annum, Post Free.

VOL. V.

No. 27.

cicncc

progress

A MONTHLY REVIEW OF CURRENT SCIENTIFIC INVESTIGATION.

Conducted by HENRY C. BURDETT.

Edited by J. BRETLAND FARMER, M.A.

WITH THE CO-OPERATION OF THE FOLLOWING EDITORIAL COMMITTEE:—

H. E. ARMSTRONG, F.R.S., Professor of Chemistry at the City and Guilds of London Institute for Technical

Education.
W. R. DUNSTAN, F.R.S., Professor of Chemistry, St. Thomas' Hospital and Pharmaceutical Society,

London.

G. F. FITZGERALD, F.R.S., Professor of Natural and Experimental Philosophy in the University of Dublin.

C. S. SHERRINGTON, F.R.S., Professor of Physiology in University College, Liverpool.

J. W. JUDD, C.B., F.R.S., Dean of the Royal College of Science, London.

W. J. SOLLAS, F.R.S., Professor of Geology in the University of Dublin.

G. B. HOWES, F.Z.S., Professor of Zoology, Royal College of Science, London.

H. MARSHALL WARD, F.R.S., Professor of Botany in the University of Cambridge.

H. A. MIERS, M.A., Professor of Mineralogy in the University of Oxford.

MAY, 1896.

CONTENTS.

THE PAST, PRESENT, AND FUTURE WATER SUPPLY OF LONDON. By E.

FRANKLAND, F.R.S

SOME RECENT MEMOIRS UPON OLIGOCH>ETA. By F. E. BEDDARD, M.A., F.R.S.

NOTES ON ATOMIC WEIGHTS. By ALEXANDER SCOTT, M.A., Jacksonian Demon-
strator in the University of Cambridge

THE STELAR THEORY: A History and a Criticism (Part II.). By A. G. TANSLEY,
B.A

THE PRESENT POSITION OF THE CELL-THEORY (Part II.). By G. C. BOURNE,
M.A. , Fellow of New College, Oxford

FERNS: APOSPOROUS AND APOGAMOUS. By C. T. DRUERY, F.L.S

APPENDICES:

I. NOTICES OF BOOKS

II. CHEMICAL LITERATURE FOR MARCH, 1896

163

190

202

215

227
242

XXI
XXV

feonfcon :
THE SCIENTIFIC PRESS, LIMITED, 428 Strand, W.C.

NEW YORK, BOSTON AND CHICAGO (Special American

Edition) : Messrs. D. C. HEATH & CO.
DUBLIN : Messrs. FANNIN & CO., 41 GRAFTON ST.
EDINBURGH: Messrs. OLIVER & BOYD.
GLASGOW: Messrs. JOHN MENZIES & CO.
TORONTO: THE TORONTO NEWS CO.
MONTREAL : THE MONTREAL NEWS CO.

BERLIN: Messrs. A. ASHER & CO.
PARIS: LIBRAIRIE GALIGNANI, 224 RUE RIVOLI.
INDIA: Messrs. THACKER AND CO.
MELBOURNE, SYDNEY, 1 Messrs. GORDON

ADELAIDE, NEW ZEALAND: f AND GOTCH.

SOUTH AFRICA: Messrs. JUTA, CAPE TOWN.
LEIPZIG: Mr. ALFRED LORENTZ.

USEFUL BOOKS FOR THE GARDEN.

THE ENGLISH FLOWEK GAEDEN. Style, position, and arrange-
ment. With a description of all the best plants for it, their culture and
arrangement. A New Edition of this book will shortly be published. The
text has been thoroughly revised and in great part rewritten ; and many new
and beautiful woodcuts, both in addition to, and in place of, those which have
already appeared, will be given. By Wm. Robinson. Medium 8vo, 15s. ; post
free, 15s. 6d.

THE VEGETABLE GAEDEN. Illustrations, Descriptions, and
Culture of the Garden Vegetables of cold and temperate climates. By MM.
Vilmorin-Andrieux of Paris. English Edition. Just published. 8vo. Illus-
trated, 15s. ; post free, 15s. 6d.

A DICTIONAEY OF ENGLISH NAMES OF PLANTS " applied

in England and among English-speaking People to Cultivated and Wild Plants,
Trees and Shrubs". In two Parts — English-Latin and Latin-English. By Wm.
Miller. 12s. ; post free, 12s. 6d. "A work of value which extends over a large
field, including cultivated native and foreign plants, trees and shrubs." — Times,
25th July, 1885.

GEEENHOUSE AND STOVE PLANTS, Floweeing and Fine-
Leaved Palms, Ferns, and Lycopodiums, with full details of the propagation
and cultivation of 50 families of plants, embracing all the best kinds in cultivation
suitable for growing in the greenhouse, intermediate hoxise and stove. By
Thomas Baines. Price 8s. 6d. ; post free, 9s.

HAEDY FLOWEES. Giving descriptions of upwards of 1300 of the

most ornamental species, with directions for their arrangement, culture, etc. Fifth
and Popular Edition. Price Is. ; post free, Is. 3d.

THE SUBTEOPICAL GAEDEN ; ok, Beauty of Form in the

Flower Garden ; with Illustrations of the finer foliage plants used for this pur-
pose. By Wm. Robinson. 5s. ; post free, 5s. 6d.

GAEDEN DESIGN AND AECHITECTS' GAEDENS. Two Ee-

views, Illustrated, to show by actual Examples from British Gardens, that clipping
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less and inartistic. By W. Robinson, F.L.S. Demy 8vo, 5s. From John Murray,
Albemarle Street, London.

THE GAEDEN ANNUAL, ALMANACK, AND ADDEESS BOOK,

FOR 1896. Containing an Almanack for the year 1896. Seasonable work fur each
Month. Flowers, fruits, and vegetables procurable each Month. New plants of the
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Weekly, 3d. ; Post Free, 3id. Monthly Parts, Is. ; Post Free, is. 3d. Annual Subscription, 17s. 6d.

THE GARDEN:

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COLOURED PLATES, FAITHFULLY DRAWN, OF MEW OR RARE PLANTS, ARE ISSUED WITH

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Weekly, Id. Monthly Parts, 5d. Yearly Subscription, 6s. 6d.

Illustrated. For Town and Country.

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T}tE GARDEN OFFICE, 37 Southampton Street, Strand, London, DJ.G.

SCIENCE.

A Weekly Journal devoted to the Advancement

of Science.

Editorial Committee: S. Newcomb, Mathematics; R. S. Woodward, Mechanics;
E. C. Pickering, Astronomy ; T. C. Mendenhall, Physics; R. H. Thurston,
Engineering; Ira Remsen, Chemistry; Joseph Le Conte, Geology; W. M.
Davis, Physiography; O. C. Marsh, Paleontology; W. K. Brooks, Inverte-
brate Zoology; S. H. Scudder, Entomology; C. Hart Merriam, Vertebrate
Zoology; N. L. Britton, Botany; Henry F. Osborn, General Biology; H.
P. Bowditch, Physiology; J. S. Billincs, Hygiene; J. McKeen Cattell,
Psychology ; Daniel G. Brinton, J. W. Powell, Anthropology.

SCIENCE holds the position in America that is held
by Nature in England. It reports on the progress of
science with special reference to the most recent work
of American men of science. Science is making rapid
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SOME REASONS

FOR INSURING IN AND WORKING FOR

THE MUTUAL LIFE

hichhhd h. m curdy, INSURANCE COMPANY OF

President.

NEW YORK.

It is financially strong.

Assets December 31st, 1895 £45,276,564

Liabilities ,, „ £39,907,014

Surplus „ „ £5,369,550

It is purely/ Mutual.

There are no Shareholders to make a profit out of the Policy-holders, who
receive all the many benefits that come from entering an Institution of the highest
standing, whose position has been made by the co-operation of two generations of
Policy-holders and officials.

Its past record is magnificent.

It has received from its Policy-holders £116,344,352

It has paid to its Policy-holders £84,658,005

And besides holding the balance of £31,686,347

It has earned for its Policy-holders £13,590,217

Thus it now holds for its Policy-holders £45,276,564

Its present position is splendid.

The Insurance Department of the State of New York recently completed a
thorough examination of the Company, and the Report of the State Superintendent,
dated 17th July, 1895, certifies: —

" That the Company is solvent and strong, and is conducted in all respects in
accordance with law and sound business principles. It merits, in all respects, the
confidence of the insured, and the community at large."

Its future is certain.

" That which they have done but earnest of the things that they shall do." —
Tennyson.

Insurance is a provision for the future, and it is above all things necessary to
entrust that future to an Institution too well founded, too great to be destroyed
by any of the vicissitudes of an unknown future.

Its Policies meet all needs.

The Company issues many kinds of policies and by means of them provides for
every contingency that can be reasonably looked for.

Apply for Particulars to any of the Branch Offices or to

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D. C. HALDEMAN, General Manager.

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Subscription Price, TWENTY-FIVE SHILLINGS per Annum, Post Free.

VOL. V.

No. 28.

ctence

repress

A MONTHLY REVIEW OF CURRENT SCIENTIFIC INVESTIGATION.

Conducted by HENRY C. BURDETT.

Edited by J. BRETLAND FARMER, M.A.

WITH THE CO-OPERATION r'F THE FOLLOWING EDITORIAL COMMITTEE:—

H. E. ARMSTRONG, F.R.S., Professor oi Chemistry at the City and Guilds of London Institute for Technical
Education.

W. R. DUNSTAN, F.R.S., Professor of Chemistry, St. Thomas' Hospital and Pharmaceutical Society,
London.

G. F. FITZGERALD, F.R.S., Professor of Natural and Exrsrimental Philosophy in the University of Dublin.

C. S. SHERRINGTON, F.R.S., Profess*-'- pf Physiology in University College, Liverpool.

J. W. JUDD, C.3., F.R.S., Dean of the Rayr.i College of Science, London.

W. J. SOLLAS, F.R.S., Professor o* Geology in the University of Dublin.

G. B. HOWES, F.Z.S., Professor of Zoology, Royal College of Science, London.

H. MARSHALL WARD, F.R.S., Professor of Botany in the University of Cambridge.

H. A. MIER3, M.A., Professor of Mineralogy in the University of Oxford.

JUNE, 1896.

CONTENTS.

THE GROWTH OF OUR KNOWLEDGE OF HELIUM. By J. NORMAN LOCKYER
C.B., F.R.S

INSULAR FLORAS (Part V!.a). By W. HOTTING HEMSLEY, F.R.S

THE PRESENT POSITION OF THE CELL-THEORY (Concluded). By G. C
pOURNE, M.A., Fellow of New College, Oxford

THE HEREDITARY TRANSMISSION OF MICRO-ORGANISMS. By G. A

BUCKMASTER, M.D., Lecturer on Physiology at St. George's Hospital, London

249
286

304

324

APPENDICES :

I. NOTICES OF BOOKS

II. CHEMICAL LITERATURE FOR MAY, ^896 ...

... XXXI
... XXXIII

THE SCIENTIFIC PRESS, LIMITED, 428 Strand, W.C.

NEW YORK. BOSTON AND CHICAGO (Special American BERLIN: Messrs. A. ASHER & CO.

Edition) : Messrs. D. C. HEATH ft CO.
DUBLIN: Messrs. FANNIN & CO., 4; GRAFTON 5T.
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BURDETT'S HOSPITALS AND
CHARITIES, 1896,

Being the Year-book of Philanthropy.

Containing a Review of the Position and Requirements of the Voluntary Charities, and an exhaustive
Record of Hospital Work for the year. It will also be found to be the most Useful and Reliable
Guide to British, Colonial, and American Hospitals, Dispensaries, Nursing and Convalescent
Institutions and Asylums.

Edited by HENRY C. BURDETT.

" Still remains the standard work of reference upon all points which relate to charities, British,
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" The book is, indeed, almost a necessary one for those who are professionally concerned in the
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" This excellent work may fairly claim to be one of the completes! — if it is not the completest — 01
its kind." — The Guardian.

Just Out. Foolscap Svo. Profusely Illustrated. Cloth, 6s.

Clinical Diagnosis:

A Practical Handbook of Chemical and Microscopical

Methods.

By W. Q. AITCHISON ROBERTSON, M.D., D.Sc, F.R.C.P.Ed.,

Author of " On the Growth of Dentine," " The Digestion of Sugars," etc.

To the student studying Clinical Medicine, as well as to the busy practitioner, to whom time is of
importance, the value of a practical handbook of this kind will at once be evident.

Only those methods are given which have been found easy, rapid and reliable, neither requiring
much chemical skill nor elaborate apparatus. Mere working details are stated and no theories indulged
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Demy Svo, with Tivo Plates, handsome cloth gilt, over 400 pp., 12s. 6d. int.

Medical History from the Earliest Times.

By E. T. WITHINGTON, M.A., M.B., Oxon.

This important history of Medicine from the earliest times has been treated in an exhaustive and
thorough manner. It comprises sixty-five chapters and seven appendices, commencing with Medicine
in Pre-historic Times, and ending with the Origin of Modern Medicine.

" One of the best attempts that has yet been made in the English language to present the reader
with a concise epitome of the history of medicine, and as such we cordially commend it." — Glasgow
Medical Journal.

" This learned but fascinating volume may be recommended to all readers." — Daily Chronicle.

Demy Svo, profusely illustrated with Coloured and other Plates and Drawings, 5s. net.

Lectures on Genito-Urinary Diseases.

By J. C. OQILVIE WILL, M.D., CM., F.R.S.E.,

Consulting Surgeon to the Aberdeen Royal Infirmary, and Examiner in Surgery in the University of Aberdeen.

Contexts. — Urethral Fever and Catheter Fever — Treatment of Retention of Urine — Gleet and its
Treatment — On Varicocele — On Hydrocele — The Treatment of Syphilis — Appendix — Prescriptions for
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"We have no hesitation in recommending Dr. Ogilvie Will's work." — The Practitioner.

Foolscap Svo, cloth gilt, 2S. {post free).

Myxoedema :

And the Effect of Climate on the Disease,

By A. MARIUS WILSON, M.D., B.S., L.R.C.P.Lond., M.R.C.S.Eng.

A valuable little treatise on a subject about which comparatively little has been written. The special
feature of this work is its treatment of the effects of climate upon the disease.

Just Published, bd.

The Schott Treatment of Heart Disease.

By RICHARD GREENE, F.R.C.P.Ed.

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SCIENCE.

A Weekly Journal devoted to the Advancement

of Science.

Editorial Committee : S. Newcomb, Mathematics ; R. S. Woodward, Mechanics;
E. C. Pickering, Astronomy; T. C. Mendenhall, Physics; R. H. Thurston,
Engineering; Ira Remsen, Chemistry; Joseph Le Conte, Geology; W. M.
Davis, Physiography ; O. C. Marsh, Paleontology ; W. K. Brooks, Inverte-
brate Zoology; S. H. Scudder, Entomology; C. Hart Merriam, Vertebrate
Zoology; N. L. Britton, Botany; Henry F. Osborn, General Biology; H.
P. Bowditch, Physiology; J. S. Billincs, Hygiene; J. McKeen Cattell,
Psychology ; Daniel G. Brinton, J. W. Powell, Anthropology.

SCIENCE holds the position in America that is held
by Nature in England. It reports on the progress of
science with special reference to the most recent work
of American men of science. Science is making rapid
progress in America in all directions, and in some of its
departments is in advance of any other country. A know-
ledge of the work being accomplished is essential to all
who wish to follow the progress of science, and this can
be most conveniently and adequately secured with the aid
of this journal. We believe that it is almost necessary for
men of science in Europe either to subscribe to SCIENCE
or provide for its presence in an accessible library.

Annual Subscription, £1 Os* 6dm Single Gobies, 8dm

Address:— SCIENCE, 41 East 49th Street, New York.

SOME REASONS

FOR INSURING IN AND WORKING FOR

THE MUTUAL LIFE

Richard n. vie curdy, INSURANCE COMPANY OF

President.

NEW YORK.

It is financially strong.

Assets December 31st, 1895 £45,276,564

Liabilities „ „ £39,907,014

Surplus „ „ £5,369,550

It is purely Mutual.

There are no Shareholders to make a profit out of the Policy-holders, who
receive all the many benefits that come from entering an Institution of the highest
standing, whose position has been made by the co-operation of two generations of
Policy-holders and officials.

Its past record is magnificent.

It has received from its Policy-holders £116,344,352

It has paid to its Policy-holders £84,658,005

And besides holding the balance of £31,686,347

It has earned for its Policyholders £13,590,217

Thus it now holds for its Policy-holders £45,276,564

Its present position is splendid.

The Insurance Department of the State of New York recently completed a
thorough examination of the Company, and the Report of the State Superintendent,
dated 17th July, 1895, certifies: —

"That the Company is solvent and strong, and is conducted in all respects in
accordance with law and sound business principles. It merits, in all respects, the
confidence of the insured, and the community at large."

Its future is certain.

"That which they have done but earnest of the things that they shall do." —
Tennyson.

Insurance is a provision for the future, and it is above all things necessary to
entrust that future to an Institution too well founded, too great to be destroyed
by any of the vicissitudes of an unknown future.

Its Policies meet all needs.

The Company issues many kinds of policies and by means of them provides for
every contingency that can be reasonably looked for.

Apply for Particulars to any of the Branch Offices or to

Head Office for the United Kingdom : 17 & 18 CORNHILL, LONDON, E.C.

D. C. HALDEMAN, General Manager.

Price HALF-A-CROWN.
Subscription Price, TWENTY-FIVE SHILLINGS per Annum, Post Free

VOL. V.

No. 29.

cience

A MONTHLY REVIEW OF CURRENT SCIENTIFIC INVESTIGATION.

Conducted by HENRY C. BURDETT.

Edited by J. BRETLAND FARMER, M.A.

WITH THE COOPERATION OF THE FOLLOWING EDITORIAL COMMITTEE:—

H. E. ARMSTRONG, F.R.S., Professor of Chemistry at the City and Guilds of London Institute for Technical
Education.

W. R. DUNSTAN, F.R.S., Professor of Chemistry, St. Thomas' Hospital and Pharmaceutical Society,
London.

G. F. FITZGERALD, F.R.S., Professor of Natural and Experimental Philosophy in the University of Dublin.

C. S. SHERRINGTON, F.R.S., Professor of Physiology in University College, Liverpool.

J. W. JUDD, C.B., F.R.S., Dean of the Royal College of Science, London.

W. J. SOLLAS, F.R.S., Professor of Geology in the University of Dublin.

G. B. HOWES, F.Z.S., Professor of Zoology, Royal College of Science, London.

H. MARSHALL WARD, F.R.S., Professor of Botany in the University of Cambridge.

H. A. M1ERS, F. R.S., Professor of Mineralogy in the University of Oxford.

JULY, 1896.

CONTENTS.

PAGE

PREHISTORIC MAN IN THE EASTERN MEDITERRANEAN. By J. L. MYRES,

Fellow of Magdalen College, Oxford ... ... ... ... ... ... ... ... ... 335

THE GRAPTOLITES. By J. E. MARR, M.A., F.R.S., Fellow of St. John's College,

Cambridge ... ... ... ... ... ... ... ... ... ... ... ... 360

INSULAR FLORAS (Part VI. b). By W. BOTTING HEMSLEY, Royal Herbarium, Kew 374

SELECTION IN MAN. By JOHN BEDDOE, M.D., LL.D., F.R.S 384

RECENT DISCOVERIES IN AVIAN PAL/EONTOLOGY. By C. W. ANDREWS ... 398

APPENDICES :

I. NOTICES OF BOOKS

II. CHEMICAL LITERATURE FOR JUNE, 1896

XLI
XLII

feon&on :
THE SCIENTIFIC PRESS," LIMITED, 428 Strand, W.C.

NEW YORK. BOSTON AND CHICAGO (Special American

Edition) : Messrs. D. C. HEATH & CO.
DUBLIN : Messrs. FANNIN & CO., 41 GRAFTON ST.
EDINBURGH: Messrs. OLIVER & BOYD.
GLASGOW: Messrs. JOHN MENZIES & CO.
TORONTO: THE TORONTO NEWS CO.
MONTREAL: THE MONTREAL NEWS CO.

BERLIN: Messrs. A. ASHER & CO.
PARIS: LIBRAIRIE GALIGNANI, 224 RUE RIVOLI.
INDIA: Messrs. THACKER AND CO.
MELBOURNE, SYDNEY, ) Messrs. GORDON

ADELAIDE, NEW ZEALAND:* AND GOTCH.

SOUTH AFRICA: Messrs. JUTA, CAPE TOWN.
LEIPZIG: Mr. ALFRED LORENTZ.

THE SCiENTJFJC^RE&S LIST. !

Seventh year of publication. Crown 8vo, about iooo pp. Scarlet cloth, gilt lettered, 55.

BURDETT'S HOSPITALS AND
CHARITIES, 1896,

Being the Year-book of Philanthropy.

Containing a Review of the Position and Requirements of the Voluntary Charities, and an exhaustive
Record of Hospital Work for the year. It will also be found to be the most Useful and Reliable
Guide to British, Colonial, and American Hospitals, Dispensaries, Nursing and Convalescent
Institutions and Asylums.

Edited by HENRY C. BURDETT.

" This is the seventh year of publication of this invaluable manual, a volume which contains a
quite exhaustive statement of its subject. What Hospitals do, for whom they do it, by whose help,
and at whose cost, are every one of them questions of the profoundest interest, and they find their
answer here." — Spectator.

" There is no better work of reference dealing with the wide province of medical and general
relief." — Guardian.

Just Out. Foolscap Svo. Profusely Illustrated. Cloth, 6s.

ClinicaB Diagnosis:

A Practical Handbook of Chemical and ftflicroscopical

Methods,

By W. Q. AITCHISON ROBERTSON, M.D., D.Sc, F.R.C.P.Ed.,

Author of " On the Growth of Dentine," " The Digestion of Sugars," etc.
" Students and practitioners ought to welcome heartily a handbook like the one before us, which con-
tains the facts and nothing else, which without any pretence of literary veneer accurately and succinctly
offers to one who is about to undertake the chemical or microscopical investigation of any specimen or
any organ, just those points which he ought to know, describes exactly the methods he ought to pursue,
mentions the things he ought to have at hand, and, if we may be allowed the expression, gives a recipe
for the making of the investigation." — Hospital.

Demy Svo, with Two Plates, handsome cloth gilt, over 400 pp., 12s. 6d. net.

Medical History from the Earliest Times.

By E. T. WITHINGTON, M.A., M.B., Oxon.

This important history of Medicine from the earliest times has been treated in an exhaustive and
thorough manner. It comprises sixty-five chapters and seven appendices, commencing with Medicine
in Pre-historic Times, and ending with the Origin of Modern Medicine.

" One of the best attempts that has yet been made in the English language to present the reader
with a concise epitome of the history of medicine, and as such we cordially commend it." — Glasgow
Medical Journal.

" This learned but fascinating volume may be recommended to all readers." — Daily Chronicle.

LONDON : THE SCIENTIFIC PRESS, LIMITED, 428 STRAND, W.C.

AND

ILLUSTRATED ARCHAEOLOGIST.

Edited by </. ROMiLLY ALLEN, F.S.A.

PRICE 2s. 6d. QUARTERLY.
CONTENTS OF JULY PART.

Some Forms of Greek Idolatry. II.— Hermai and Xoana. By G. F. Hill. 5 Illustrations.

The Old Stone Crosses of Somersetshire. Part II. By Alex. Gordon. 14 Illustrations.

Churchyard Games in Wales. By Elias Owen, M.A., F.S.A. 5 Illustrations.

Cornish Bench-Ends. By Arthur G. Langdon. 10 Illustrations.

Notes on French Dolmens. By Robert Burnard. 4 Illustrations.

Wall Paintings at Ashampstead, Berks.

Two Sepulchral Urns from the North-East of Scotland. 2 Illustrations.

Devices for the Protection of Food against Vermin, in Use amongst Savage Peoples.

2 Illustrations.
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" Pre-Historic Man in Ayrshire," by John Smith— " The Histories of Manningham, Heaton, and Allerton," by William
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LONDON: BEMROSE & SONS, LTD., 23 Old Bailey, and Derby.

USEFUL BOOKS FOR THE GARDEN.

THE ENGLISH FLOWEE GAEDEN. Style, position, and arrange-
ment. With a description of all the best plants for it, their culture and
arrangement. A New Edition of this book will shortly be published. The
text has been thoroughly revised and in great part rewritten; and many new
and beautiful woodcuts, both in addition to, and in place of, those which have
already appeared, will be given. By Wm. Robinson. Medium 8vo, 15s. ; post
free, 15s. 6d.

THE VEGETABLE GAEDEN. Illustrations, Descriptions, and
Culture of the Garden Vegetables of cold and temperate climates. By MM.
Vilmorin-Andrieux of Paris. English Edition. Just published. 8vo. Illus-
trated, 15s. ; post free, 15s. 6d.

A DICTIONAEY OF ENGLISH NAMES OF PLANTS "applied

in England and among English-speaking People to Cultivated and Wild Plants,
Trees and Shrubs". In two Parts — English-Latin and Latin-English. By War.
Miller. 12s. ; post free, 12s. 6d. "A work of value which extends over a, large
field, including cultivated native and foreign plants, trees and shrubs." — Times,
25th July, 1885.

GEEENHOUSE AND STOVE PLANTS, Flowering and Fine-
Leaved Palms, Ferns, and Lycopodiums, with full details of the propagation
and cultivation of 50 families of plants, embracing all the best kinds in cultivation
suitable for growing in the greenhouse, intermediate house and stove. By
Thomas Baines. Price 8s. 6d. ; post free, 9s.

HAEDY FLOWEES. Giving descriptions of upwards of 1300 of the
most ornamental species, with directions for their arrangement, culture, etc. Fifth
and Popular Edition. Price Is. ; post free, Is. 3d.

THE SUBTEOPICAL GAEDEN ; or, Beauty of Form in the

Flower Garden ; with Illustrations of the finer foliage plants used for this pur-
pose. By Wm. Bobinson. 5s. ; post free, 5s. 6d.

GAEDEN DESIGN AND AECHITECTS' GAEDENS. Two Be-

views, Illustrated, to show by actual Examples from British Gardens, that clipping
and aligning trees to make them "harmonise" with architecture is barbarous, need-
less and inartistic. By W. Robinson, F.L.S. Demy 8vo, 5s. From John Murray,
Albemarle Street, London.

THE GAEDEN ANNUAL, ALMANACK, AND ADDEESS BOOK,

FOR 1896. Containing an Almanack for the year 1896. Seasonable work for each
Month. Flowers, fruits, and vegetables procurable each Month. New plants of the
past year. Alphabetical List of Nurserymen, Seedsmen, and Florists. List of
Horticultural Builders, etc., etc. Lists of Gardens, Country Seats, and Gardeners.
Price Is. ; post free, Is. 3d.

Weekly, 3d. ; Post free, 3^d. Monthly Parts, Is. ; Post Free, Is. 3d. Annual Subscription, 17s. 6d.

THE Oi^RDEN:

An Illustrated Journal of Horticultuie in all its Branches.

COLOURED PLATES, FAITHFULLY DRAWN, OF NEW OR RARE PLANTS, ARE ISSUED WITH

EACH NUMBER.

Weekly, Id. Monthly Parts, 5d. Yearly Subscription, 6s. 6d.

Illustrated. For Town and Country.

The Paper for Amateur and Villa Gardeners, Suburban, Cottage, and Town
Gardening. Window Plants, Bees, Poultry, etc.

TjiE GffiW OFFICE, 37 Sooifiampioo Street, Strand, London, ill.C.

SOME REASONS

FOR INSURING IN AND WORKING FOR

THE MUTUAL LIFE

richard r. ivic curdy, INSURANCE COMPANY OF

President.

NEW YORK.

It is financially? strong.

Assets December 31st, 1895 £45,276,564

Liabilities ,, „ £39,907,014

Surplus ,, „ £5,369,550

It is purely mutual. \

There are no Shareholders to make a profit out of the Policy-holders, who
receive all the many benefits that come from entering an Institution of the highest
standing, whose position has been made by the co-operation of two generations of
Policy-holders and officials.

Its past record is magnificent*

It has received from its Policy-holders £116,344,352

It has paid to its Policy-holders £84,658,005

And besides holding the balance of £31,686,347

It has earned for its Policy-holders £13,590,217

Thus it now holds for its Policy-holders £45,276,564

Its present position is splendid.

The Insurance Department of the State of New York recently completed a
thorough examination of the Company, and the Report of the State Superintendent,
dated 17th July, 1895, certifies: —

" That the Company is solvent and strong, and is conducted in all respects in
accordance with law and sound business principles. It merits, in all respects, the
confidence of the insured, and the community at large."

Its future is certain.

" That which they have done but earnest of the things that they shall do." —
Tennyson .

Insurance is a provision for the future, and it is above all things necessary to
entrust that future to an Institution too well founded, too great to be destroyed
by any of the vicissitudes of an unknown future.

Its Policies meet all needs.

The Company issues many kinds of policies and by means of them provides for
every contingency that can be reasonably looked for.

Apply for Particulars to auv of the Branch Offices or to

Head Office for the United Kingdom : 17 & 18 GORNHILL, LONDON, E.C.

D. C. HALDEMAN, General Manager.

Price HALF-A-CROWN. 7

Subscription Price, TWENTY-FIVE SHILLINGS per Annum, Post Free.

VOL. V.

No. 30.

ctence

A MONTHLY REVIEW OF CURRENT SCIENTIFIC INVESTIGATION.

Conducted by HENRY C. BURDETT.

Edited by J. BRETLAND FARMER, M.A.

WITH THE COOPERATION OF THE FOLLOWING EDITORIAL COMMITTEE:—

Professor of Chemistry at the City and Guilds of London Institute for Technical

Professor of Chemistry, St. Thomas' Hospital and Pharmaceutical Society,

H. E. ARMSTRONG, F.R.S
Education.

W. R. DUNSTAN, F.R.S.
London.

G. F. FITZGERALD, F.R.S., Professor of Natural and Experimental Philosophy in the University of Dublin.

C. S. SHERRINGTON, F.R.S., Professor of Physiology in University College, Liverpool.

J. W. JUDD, C.B., F.R.S., Dean of the Royal College of Science, London.

W. J. SOLLAS, F.R.S., Professor of Geology in the University of Dublin.

G. B. HOWES, F.Z.S., Professor of Zoology, Royal College of Science, London.

H. MARSHALL WARD, F.R.S., Professor of Botany in the University of Cambridge.

H. A. M1ERS, F.R.S., Professor of Mineralogy in the University of Oxford.

AUGUST, 1896.

CONTENTS.
By OLIVER LODGE, F.R.S., Professor of Physics

By A. C. SEWARD, M.A., F.G.S.,

By PHILIP LAKE,

LIGHT AND ELECTRIFICATION, II

in University College, Liverpool

AN EXTINCT PLANT OF DOUBTFUL AFFINITY

University Lecturer in Botany, Cambridge ...

THE WORK OF THE PORTUGUESE GEOLOGICAL SURVEY.

M.A., St John's College, Cambridge ...

IODINE IN THE ANIMAL ORGANISM. By W. D. HALLIBURTON, M.D., F.R.S., Pro-
fessor of Physiology in King's College, London

PETROLOGY IN AMERICA. By ALFRED HARKER, M.A., Fellow of St. John's College,
Cambridge

GOLD EXTRACTION PROCESSES. By T. K. ROSE, D.Sc, Assistant Assayer of the
Royal Mint

RECENT VALUES OF THE MAGNETIC ELEMENTS AT THE PRINCIPAL MAG
NETIC OBSERVATORIES OF THE WORLD. By Charles Chree, M.A., Superin-
tendent of the Kew Observatory

APPENDIX:

CHEMICAL LITERATURE FOR JUNE, 1896

PAGE

417

427

439

454

459

484

499

XLVII

THE SCIENTIFIC PRESS, LIMITED, 428 Strand, W.C

NEW YORK, BOSTON AND CHICAGO (Special American

Edition) : Messrs. D. C. HEATH & CO.
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LEIPZIG: Mr. ALFRED LORENTZ.

THE SCIENJIFIC^PRESS LIST. \

Seventh year of publication. Crown 8vo, about iooo pp. Scarlet cloth, gilt lettered, 55.

BURDETTS HOSPITALS AND
CHARITIES, 1896,

Being the Year-book of Philanthropy.

Containing a Review of the Position and Requirements of the Voluntary Charities, and an exhaustive
Record of Hospital Work for the year. It will also be found to be the most Useful and Reliable
Guide to British, Colonial, and American Hospitals, Dispensaries, Nursing and Convalescent
Institutions and Asylums.

Edited by HENRY C. BURDETT.

" This is the seventh year of publication of this invaluable manual, a volume which contains a
quite exhaustive statement of its subject. What Hospitals do, for whom they do it, by whose help,
and at whose cost, are every one of them questions of the profoundest interest, and they find their
answer here." — Spectator.

" There is no better work of reference dealing with the wide province of medical and general
relief." — Guardian.

fust Out. Foolscap 8vo. Profusely Illustrated. Cloth, 6s.

Clinical Diagnosis:

A Practical Handbook of Chemical and Microscopical

Methods.

By W. Q. A1TCH1SON ROBERTSON, M.D., D.Sc, F.R.C.P.Ed.,

Author of " On the Growth of Dentine," " The Digestion of Sugars," etc.
" Students and practitioners ought to welcome heartily a handbook like the one before us, which con-
tains the facts and nothing else, which without any pretence of literary veneer accurately and succinctly
offers to one who is about to undertake the chemical or microscopical investigation of any specimen or
any organ, just those points which he ought to know, describes exactly the methods he ought to pursue,
mentions the things he ought to have at hand, and, if we may be allowed the expression, gives a recipe
for the making of the investigation." — Hospital.

In the press. Ready early in September. Price 7s. 6d. net.

The Menopause and its Disorders.

By A. D. LEITH NAPIER, M.D., M.R.C.P., etc.,

Editor of the British Gynecological Journal ; Author of " Notes on Puerperal Fever," " The Thermometer in Obstetrics and

Gynaecology," etc., etc.

LONDON: THE SCIENTIFIC PRESS, LIMITED, 428 STRAND, W.C.

AND

ILLUSTRATED ARCH/EOLOGIST.

Edited by J. ROM ILLY ALLEN, F.S.A.

PRICE 2s. 6d. QUARTERLY.

CONTENTS OF JULY PART.

Some Forms of Greek Idolatry. II.— Hermai and Xoana. By G. F. Hill. 5 Illustrations.

The Old Stone Crosses of Somersetshire. Part II. By Alex. Gordon. 14 Illustrations.

Churchyard Games in Wales. By Elias Owen, M.A., F.S.A. 5 Illustrations.

Cornish Bench-Ends. By Arthur G. Langdon. 10 Illustrations.

Notes on French Dolmens. By Robert Burnard. 4 Illustrations.

Wall Paintings at Ashampstead, Berks.

Two Sepulchral Urns from the North-East of Scotland. 2 Illustrations.

Devices for the Protection of Food against Vermin, in Use amongst Savage Peoples.

2 Illustrations.
Memorial to the late Prof. Dr. George Stephens of Copenhagen.
Notices of New Publications—

" Pre-Historic Man in Ayrshire," by John Smith— " The Histories of Manningham, Heaton, and Allerton," by William
Cudworth— " English Pottery and Porcelain," by Ed. A. Downman — " The Archaeological Report of the Egypt Explora-
tion Fund " — " The Transactions of the Monumental Brass Society " — " Middlesex and Hertfordshire Notes and Queries,"
edited by Mr. W. J. Hardy, F.S.A.—" Zeitschrift fur Celtische Philologie," edited by Kuno Meyer and L. Chr. Stern—
" History of the Parish of West or Old Kilpatrick," Part IV., by John Bruce—" Alphabets," by E. F. Strange—" Old
Cornish Crosses," by Arthur G. Langdon.

LONDON: BEMROSE & SONS, LTD., 23 Old Bailey, and Derby.

USEFUL BOOKS FOR THE GARDEN.

THE ENGLISH FLOWEE GAEDEN. Style, position, and arrange-

ment. With a description of all the best plants for it, their culture and
arrangement. A New Edition of this book will shortly be published. The
text has been thoroughly revised and in great part rewritten ; and many new
and beautiful woodcuts, both in addition to, and in place of, those which have
already appeared, will be given. By Wm. Robinson. Medium 8vo, 15s. ; post
free, 15s. 6d.

THE VEGETABLE GAEDEN. Illustrations, Descriptions, and
Culture of the Garden Vegetables of cold and temperate climates. By MM.
Vilmorin-Andrieux of Paris. English Edition. Just published. 8vo. Illus-
trated, 15s. ; post free, 15s. 6d.

A DICTIONAEY OF ENGLISH NAMES OF PLANTS " applied

in England and among English-speaking People to Cultivated and Wild Plants,
Trees and Shrubs". In two Parts — English-Latin and Latin-English. By Wm.
Miller. 12s. ; post free, 12s. 6d. "A work of value which extends over a large
field, including cultivated native and foreign plants, trees and shrubs."— Times,
25th July, 1885.

GEEENHOUSE AND STOVE PLANTS, Floweeing and Fine-
Leaved Palms, Ferns, and Lycopodiums, with full details of the propagation
and cultivation of 50 families of plants, embracing all the best kinds in cultivation
suitable for growing in the greenhouse, intermediate house and stove. By
Thomas Baines. Price 8s. 6d. ; post free, 9s.

HAEDY FLO WEES. Giving descriptions of upwards of 1300 of the

most ornamental species, with directions for their arrangement, culture, etc. Fifth
and Popular Edition. Price Is. ; post free, Is. 3d.

THE SUBTEOPICAL GAEDEN ; or, Beauty of Form in the

Flower Garden ; with Illustrations of the finer foliage plants used for this pur-
pose. By Wm. Robinson. 5s. ; post free, 5s. 6d.

GAEDEN DESIGN AND AECHITECTS' GAEDENS. Two Ee-

views, Illustrated, to show by actual Examples from British Gardens, that clipping
and aligning trees to make them " harmonise " with architecture is barbarous, need-
less and inartistic. By W. Robinson, F.L.S. Demy 8vo, 5s. From John Murray,
Albemarle Street, London.

THE GAEDEN ANNUAL, ALMANACK, AND ADDEESS BOOK,

FOR 1896. Containing an Almanack for the year 1896. Seasonable work for each
Month. Flowers, fruits, and vegetables procurable each Month. New plants of the
past year. Alphabetical List of Nurserymen, Seedsmen, and Florists. List of
Horticultural Builders, etc., etc. Lists of Gardens, Country Seats, and Gardeners.
Price Is. ; post free, Is. 3d.

Weekly, 3d. ; Post free, 3^d. Monthly Parts, Is. ; Post Free, is. 3d. Annual Subscription, 17s. 6d.

THE GARDEN:

An Illustrated Journal of Horticultute in all its Branches.

COLOURED PLATES, FAITHFULLY DRAWN, OF NEW OR RARE PLANTS, ARE ISSUED WITH

EACH NUMBER.

Weekly, Id. Monthly Parts, 5d. Yearly Subscription, 6s. 6d.

a-ABDEisri]sra-.

Illustrated. For Town and Country.

The Paper for Amateur and Villa Gardeners, Suburban, Cottage, and Town
Gardening. Window Plants, Bees, Poultry, etc.

THE GftRBEN OFFICE, 37 Southampton Street, Strand, London, UJ.C.

SOME REASONS

FOR INSURING IN AND WORKING FOR

THE MUTUAL LIFE

HicHRHD a. nc curdy, INSURANCE COMPANY OF

President.

NEW YORK.

It is financially strong.

Assets December 31st, 1895 £45,276,564

Liabilities ,, „ £39,907,014

Surplus ,, „ £5,369,550

It is purely Mutual.

There are no Shareholders to make a profit out of the Policy-holders, who
receive all the many benefits that come from entering an Institution of the highest
standing, whose position has been made by the co-operation of two generations of
Policy-holders and officials.

Its past record is magnificent.

It has received from its Policy-holders £116,344,352

It has paid to its Policy-holders £84,658,005

And besides holding the balance of £31,686,347

It has earned for its Policy-holders £13,590,217

Thus it now holds for its Policy-holders £45,276,564

Its present position is splendid.

The Insurance Department of the State of New York recently completed a
thorough examination of the Company, and the Report of the State Superintendent,
dated 17th July, 1895, certifies: —

" That the Company is solvent and strong, and is conducted in all respects in
accordance with law and sound business principles. It merits, in all respects, the
confidence of the insured, and the community at large."

Its future is certain.

" That which they have done but earnest of the things that they shall do."—
Tennyson.

Insurance is a provision for the future, and it is above all things necessary to
entrust that future to an Institution too well founded, too great to be destroyed
by any of the vicissitudes of an unknown future.

Its Policies meet all needs.

The Company issues many kinds of policies and by means of them provides for
every contingency that can be reasonably looked for.

Apply for Particulars to any of the Branch Offices or to

Head Office for the United Kingdom : 17 & 18 CORNHILL, LONDON, E.G.

D. C. HALDEMAN, General Manager.

MBL/WHOI LIBRARY

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