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HARVARD UNIVERSITY.

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Sturgis Hooper Professor

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THE
GEOLOGICAL MAGAZINE.
DECADE II, VOL. V.

JANUARY—DECEMBER. 1878.

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MAGAZINE:

Monthly Journal of Geologn :

WITH WHICH IS INCORPORATED

GEOLOGICAL

ME GHOLOG ES @-

NOS. CLXIII. TO CLXXIV.

EDITED BY

HENRY WOODWARD, LL.D., F.B.S., F.G.8., F.Z.S.,

VICE-PRESIDENT OF THE GEOLOGISTS ASSOCIATION ;

MEMBER OF THE AMERICAN PHILOSOPHICAL SOCIETY, PHILADELPHIA ;

HONORARY MEMBER OF THE YORKSHIRE PHILOSOPHICAL SOCIETY; OF THE GEOLOGICAL SOCIETIES
OF EDINBURGH, GLASGOW, AND NORWICH; CORRESPONDING MEMBER OF THE GEOLOGICAL
SOCIETY OF BELGIUM; OF THE NATURAL HISTORY SOCIETY OF MONTREAL; AND
OF THE LYCEUM OF NATURAL HISTORY, NEW YORK.

ASSISTED BY
PROFESSOR JOHN MORRIS, M.A, F.GS., &., &.,

ROBERT ETHERIDGE, F.R.S.L. & E., F.G.S., &c.

NEW SERIES. DECADE II. VOL. V.
JANUARY—DECEMBER, 1878.

LONDON:

TRUBNER.@ Co, 57 ann 59, LUDGATE HYEL
F. SAVY, 77, BOULEVART ST.-GERMAIN, PARIS.
© 1878.

HERTFORD:
PRINTED BY STEPHEN AUSTIN AND SONS

LIST OF PLATES.

PLATES. PAGE
oes Jberse noloiine WE) CLAGLISSCHOMS: ass ste ee oe aie 12
FL anaes CONG IW Men Oi IEW S een eee ee) eee fees cece oat dea cs Nise 49 -
CMO.) LENO SINT I Oona REAL): citee! teats. ersy| Gere emer lentes fait) eden ees | Coxesns eee 100
IM, Jeep e0IS Soa D08, Vl NWVOOGN AEE! ces) oe cas ee) ee | Gi 164
v V. The Coast of South Devon near Sharkham Point 0.0. cee cee 193

v VI. To illustrate Mr. Champernowne’s paper on the Devonians of North

ands South) consi ce inn es Seta, eae ae 193

“ VII. Preatya scabrosa, H. Woodward. Atya scabra, Leach. o.oo 289

v VIII. Saurocephalus Woodwardii, W. Davies and Erisichthe Dizxont, Cope ..... 254

v IX. Profile of Volcanos traced from Photographs... 0 ce cee ee tee 337

kere ArrctreyHossilsstrom Beeches lan cllimsgg ea eres iss bl cerinece-serees 386

« Xl. Brachypyge carbonis, HW. Woodward... 2 oe ee cee 433

Me OU GG) Ibrongtare demu Cue Mera NOLAN ccd | ercopeisenrcs | came adres aie) catego eeeo! eee 445

Papxciliiem@erotesson ma Morrisy MieAc eb Ge Sem see trial a nivenwrea se ato 481
v XIV. Professor Robt. Harkness, F.R.S.,F.G.S. .... sank A an uyeae a74

Mie
i

LIST OF WOODCUTS.

PAGE
Section of the Irkut Valley (after M. Tchersky)..... 00.0 ce cee ote sane * 31
IDOE cos eos Aci oto eG sce a 64
Section across the Valley near Dowdjoa, Shantung 2. ee. see tee oe 70
Section across Jersey from Nast to West... cece cesce cee eee ee sete ore 83
Section in Stone Pit, near Bittadon owe, ee cee tees i esi aa 208
IDGOSONIEUEP SOONG Gen See aes GG ee ee oS 221
Section from Mohawk River to Catskill Mountains ok tee see oe 271
Section through the Escarpment overlooking the village of Schoharie,

SOI NCO, JMMCENI? oes re an See cos) Voodoo, pam cael [ote 272
SECON saRaIE, IDEN TG) SESE Oe Ny MOMS Aen Ae eee Gee So 273
Section across the River Cam, from the Royal Observatory to Barnwell, near

Camibridoes eer eR a fame essen Parte Wvatad piseeaniy retin) Pivense cst, joa 402
Section across the Pennine Anticlinal 00 c, cece stesso tteee tees solar 504
Meyeria Willettii, H, Woodw., Chalk, Lewes .... ... ..... Geen eg reeer ae te 557

Glyptodendron Eatonense, Claypole, U. Silurian, Ohio ou, a, ee 559

A

jpehletnt

THE

GEOLOGICAL MAGAZINE.

NEW SERIES DECADE hi VOE. Vv.

No. I—JANUARY, 1878.

@ Gaerne AS eA See cine @ alee

a —

J.—Recent Procress In PaLmonToLoey.
Being the Inaugural Address delivered before the Edinburgh Geological Society at
its 44th Anniversary Meeting on the 27th November, 1877.
By H. Aturyne Nicuonson, M.D., D.Sc., F.R.S.E.;
Professor of Natural History in the University of St. Andrews, and Swiney Lecturer
on Geology.

INCE its foundation as a Science, at the beginning of this century,

by the illustrious Cuvier, Paleontology has progressed with an
astonishing rapidity; and though theoretically belonging to the
twin sciences of Zoology and Botany, its domain is now so vast, and
the number of facts which it has accumulated is so great, that it has
every claim to rank as a distinct department of knowledge, which
cannot be fully mastered except by those who make it the subject
of special study. ‘That the number of these is daily increasing is
shown conclusively by the increased number of systematic works on
Paleontology which have appeared of late years, and not less by
the character of these. Two of these treatises, both as yet but
partially published, may be singled out for mention in this con-
nexion—namely, the ‘“‘ Handbuch der Palzeontologie ” by Professors
Zittel and Schimper, and the new “ Lethza Geognostica” by an
association of German paleontologists. The former of these, if carried
out with the fulness and accuracy which distinguish its first portion,
will be one of the most valuable and important treatises on system-
atic paleontology which we possess in any language, and will be
a fitting companion to the classical treatises of Pictet and D’Orbigny,
though it will not supersede either of these honoured works. Of
the second of these only the first part, embracing the Atlas of
Plates of Paleeozoic fossils, has as yet been issued ; but if the text be
equal to the plates, and if the various sections of the work are under-
taken by men as eminent as Ferdinand Roemer, the new “ Lethxa
Geognostica” will undoubtedly form an indispensable item in the
library of every working paleontologist.

If it be the Germans whom the student has to thank for these
new systematic treatises, it is to the English-speaking races that we
owe the latest attempts to reduce the present chaotic condition of
paleontology to order, by establishing a bibliography of the science,
and by the preparation of catalogues of the fossils of particular
formations or of particular countries. In carrying out the first of
these ends, the successful foundation of the ‘‘ Geological Record ”
must be regarded as a great step in advance. In this invaluable,

DECADE II.—VYOL. V.—NO. I. 1

2 Prof. Nicholson—Progress in Paleontology.

but necessarily dry, publication the student will find the titles of
all works and papers on geological or paleontological subjects
published during the current year throughout the world, together
with, in most cases, a short summary of their contents. The value
of such a record of contemporaneous work can hardly be over-
estimated. But in order to bring this subject to ideal perfection, it
will be necessary that there should be prepared for each country a
complete bibliographical and descriptive catalogue of all works and
memoirs dealing with its paleontology, which have been at any time
published. As regards the Invertebrate Paleontology of the North
American Continent, such a ‘Bibliographical Report” is now in
process of preparation by Prof. C. A. White and the author,
and I hope to see the thankless and laborious but useful task of
preparing a similar bibliographical record of British palesontological
literature ere long undertaken by some public-spirited paleontologist.

As regards the second point to which I have adverted, namely
the preparation of catalogues of the fossils of special formations and
special countries, something has been already accomplished, and
very much is in process of actual accomplishment.

Amongst work of this kind, which has been already done, the first
place is due to the well-known “ Thesaurus Siluricus ” of Dr. Bigsby.
It is to be regretted, however, that this veteran geologist did not
enhance the usefulness of his valuable and laborious work by the
citation of the references to, at any rate, the original descriptions
of all the species catalogued; and it is to be hoped that this defect
will be remedied in the “Thesaurus” of Devonian and Carbon-
iferous fossils which he is now engaged in preparing. In the re-
cently published “ Catalogue of the Genera and Species of American
Paleozoic Fossils,” by Mr. §. A. Miller, references to the original
descriptions of all the species quoted are given, and the usefulness
of the work to students is thus greatly increased. The magnum
opus in the way of catalogues, however, is the “Stratigraphical
Catalogue of British Fossils,” now in course of publication by Mr.
Robert Etheridge, the appearance of which will be hailed by every
student of Paleontology. A large portion of this gigantic under-
taking has, I believe, already passed through the press, and the
general plan upon which it is constructed is both scientific and
comprehensive. Not only is each recorded British species cited
under its proper place, but the quotation of each is accompanied
by a reference to the work or works in which it has been
described, together with a full synonymy of the species, and a
statement as to its known range in time and space, along with a
list of the British localities in which it has hitherto been discovered.
Mr. Robert Etheridge, jun., following, haud impari passu, in the
steps of his distinguished father, is engaged in the publication of
a similar exhaustive Catalogue of Australian Fossils,’ the general

1 A Stratigraphical Catalogue of British Fossils. By Robert Etheridge, Esq.,
F.R.S., L. & E., F.G.S. 4 vols. 4to. Clarendon Press, Oxford.

2 A Catalogue of Australian Fossils (including Tasmania and the Island of
Timor), Stratigraphically and Zoologically arranged. By Robert Etheridge, Esq.,
jun., F.G.S. 1 vol. 8vo. University Press, Cambridge.

Prof. Nicholson—Progress in Paleontology. 3

plan of which is equally comprehensive; and I am glad to learn
_ that this important contribution to our science is not only actually
completed, but that, through the liberal spirit of the University of
Cambridge, its publication has been secured, and it is now passing
through the press. When we shall have once secured a series of
catalogues of this nature, dealing with the fossils of every country,
we may for the first time expect that the complex subject of
synonymy—at present the curse and opprobrium of Palzontology—
will be brought within manageable compass.

Leaving the subject of paleeontological literature, I propose briefly
to direct your attention to some of the more important dis-
coveries which have been made in Paleontology within the last few
years; and in so doing I shall confine my short review almost
entirely to the department of Paleeozoology, if only for the reason
that I have no claim to the possession of more than a general know-
ledge of the difficult subject of Palesophytology or Fossil Botany. As
regards this latter branch of Paleontology, however, I] may just
notice the very important controversies which have of late arisen as
to whether vegetable or animal fossils are entitled to take pre-
cedence in determining the stratigraphical horizon and geological
age of any disputed group of strata, and there are at least two
instances, in which these controversies have dealt with questions of
great general interest. In one of the instances to which I allude we
find an ancient flora co-existing with a more modern fauna; and in
the other we have modern types of plants associated with old forms
of animal life; but the problem to be solved is essentially the same
in both cases. Thus in the Gas-coals of various localities in the upper-
most portion of the Bohemian coal-strata a fauna of Permian facies
(comprising characteristic Permian species of Xenacanthus, Acan-
thodes, and Palgoniscus) is met with in association with a character-
istic assemblage of Carboniferous plants. High authorities, such as
Feistmantel, Anton Fritsch, and Krejci, explain this upon the
theory that the age of the beds must be determined by the character
of their contained animal-remains, and they conclude, therefore,
that the deposits in question are to be regarded as referable to the
base of the Permian series, or rather as passage-beds between the
Carboniferous and Permian. They regard this curious phenomenon,
in fact, as being a case in which the flora of a given region has
persisted, whilst the fauna has undergone a notable modification.
On the other hand, other authorities (such as Stur and Weiss) are of
opinion that the age of the beds should be determined from the
character of the plants, and that the Bohemian Gas-coals are to
be regarded as truly Carboniferous. The balance of evidence, how-
ever, is at present decidedly in favour of the former hypothesis.

‘he second controversy to which I have referred is of much greater
importance, and concerns the boundary-line between the Cretaceous
and Tertiary deposits of North America. In the Old World, as is
well known, there is a great break between the highest Cretaceous
and the lowest Tertiary sediments—a break marked not only by
universal unconformity, but also by a great change in the character-

4 Prof. Nicholson—Progress in Paleontology.

istic fauna of the two deposits. On the other hand, in North
America the highest unquestioned Cretaceous beds (the marine de-
posits of the Fox-Hills group) are succeeded by a great series of
strata, well known as the Fort Union or Great Lignite series, the
true stratigraphical position of which has been the subject of much
dispute. These deposits consist of nearly four thousand feet of
sandstones, shales, and beds of lignite, which rest quite conformably
upon the unquestioned Cretaceous deposits of the Fox-Hills group
below, and which are succeeded unconformably by unquestioned
beds of Tertiary age. In their lower portion they contain a number
of marine organic remains, but these gradually disappear as we
ascend in the series, and its upper portion is generally characterized
‘by the remains of land and fresh-water shells, associated with a vast
abundance of vegetable fossils, chiefly of the nature of detached
Dicotyledonous leaves. The difficulty of the problem as to the real
age of this great and remarkable deposit arises chiefly from the fact
that its marine fossils are fundamentally of Cretaceous type, whilst
the remains of plants have an equally distinct Tertiary facies. Thus
we find such characteristic Cretaceous Mollusca as Inoceramus, Ammo-
nites, Baculites, and unquestionable Dinosaurians (Agathawmas) side
by side with a luxuriant flora of an essentially Tertiary aspect,
comprising such modern genera as Quercus, Acer, Populus, Ulmus,
Morus, Fagus, Juglans, Alnus, Corylus, Ilex, Platanus, Ficus, Cinna-
momum, Smilax, Laurus, Rhamnus, Magnolia, Eucalyptus, Thuya,
Sequoia, Abies, Taxodium, Sabal, etc. Whilst this association of
Cretaceous animals with Tertiary plants is undoubted, much differ-
ence of opinion obtains as to how it ought to be interpreted. On the
one hand, high authorities, such as Dr. Heer, and Professors
Lesquereux and Dana, are of opinion that the plants ought to carry
the day, and that the Lignitic Group ought to be considered as the
base of the Tertiary series. On the other hand, equally high authori-
ties, such as Meek, Hayden, Cope, and Stevenson, are of opinion
that the fauna carries more weight than the flora, and that the Fort
Union or Lignitic series should be regarded as truly the summit of
the Cretaceous. To this view Prof. Newberry, who is in the rare
position of having attained almost equal eminence in Paleeozoology
and Paleeobotany, gives his adhesion, and it is to be considered as in
every respect the most probable view, if we take into account the
fact that the disputed series is admittedly overlain unconformably by
strata of undoubted Tertiary age. Upon the whole, then, when we
take into consideration the general unreliability of terrestrial or
freshwater mollusca as tests of age, and also the often unsatisfactory
nature of stratigraphical conclusions based upon vegetable remains
only, I think we can hardly avoid arriving at the opinion that the
Great Lignitic series of North America is truly Cretaceous, though
probably of a later date than any of the recognized Cretaceous de-
posits of the Old World.

Coming next to the Invertebrates, we find that the last decade has
been prolific in discoveries and determinations of great interest and
importance, only a very few of which I can notice here, even in the

Prof. Nicholson—Progress in Paleontology. — 5

briefest manner. The first point in this connexion which demands
our attention is the immense benefit which has resulted to paleeon-
tology from the introduction of the microscope as an absolutely
indispensable instrument of paleontological research. The old
“macroscopic” method of investigation, as the Germans have
happily termed it, has been definitely abandoned; and no
paleontologist would now, except under special circumstances,
describe any doubtful or problematical Invertebrate fossil without
previously having subjected it to a rigid examination by means
of the microscope, at any rate in all cases in which his speci-
mens would allow of this mode of examination. It is impossible,
indeed, to exaggerate the immensely increased powers of observation
and description which paleontologists have acquired by the practice
of making transparent sections of fossils, suitable for microscopic
examination. Already, the results of this method of inquiry have
proved extremely important, and when its adoption has become more
universal, we may expect an even more remarkable increase of our
knowledge as to the intimate structure of many extinct forms of life,
which are at present but very imperfectly understood.

Few departments of Invertebrate Paleontology have shown the
beneficial effects of the introduction of the microscope into paleonto-
logical investigations more strikingly than is exemplified by the
Protozoa. I could not adduce a better instance of this than is afforded
by the remarkable and beautiful series of fossil sponges, which have
been generally grouped together under the name of Ventriculitide.
Though well known by their remarkable external configuration, and
unhesitatingly classified in accordance with this character alone into
genera and species, we had until lately really very little genuine
knowledge as to the structure and affinities of these old types of life.
They were originally regarded either as horny or as primitively
calcareous sponges, which had undergone silicification ; and it was
upon this view that D’Orbigny, Fromentel, and other observers re-
garded them as a special group, to which the name of Petrospongiade
was given. We know now, however, that the Ventriculitide, and a
number of other equally interesting and beautiful groups of fossil
sponges, dating from the Lower Silurian, are true siliceous sponges,
belonging to the same great section as the exquisite Venus’ Flower-
basket and Bird’s-nest Sponges (Huplectella, Holtenia, etc.) and
other Silicispongie of recent seas, or, in other words, to such now
thoroughly established divisions as the Heaactinellide and Lithistide.
While referring to this subject, it is hardly out of place to notice
the remarkable conclusions which have been reached by Zittel
and Sollas as to the condition of fossilization of these sponges,
since these conclusions materially affect our ideas as to the general
process of fossilization, and as to the mode of preservation of the
sponges and allied organisms in particular. We are all familiar
with what is termed the “silicification” of fossils. We know
that it is a very common thing to find organisms in certain strata
in a ‘‘silicified ’ condition. In other words, we know that
fossils which we can assert positively to have been originally cal-

6 Prof. Nicholson—Progress in Paleontology.

careous, such as Brachiopods, Lamellibranchs, Corals, etc., are often
found in some particular deposit to have been entirely and perfectly
converted into flint. Not only is this silicification of calcareous
organisms a very common phenomenon, but there is not the least
difficulty in understanding how it occurs, since carbonate of lime is
a very soluble substance and flint is a very insoluble one. Hence,
any calcareous fossil, if subjected to percolation by water holding
silica in solution, would be liable to have its lime dissolved away,
and replaced by the more intractable flint. It is asserted, however,
that in the case of the fossil sponges of which I have been speaking,
as well as of some other fossils, the reverse change sometimes takes
place, and that a structure originally siliceous becomes converted into
carbonate of lime, or, rather, becomes replaced by this substance.
It must be admitted that it is at present very difficult to comprehend
how a skeleton of comparatively insoluble silica should be dis-
solved away, and should be replaced by the very readily soluble
calcite, but the researches of Zittel in particular seem to leave no
doubt as to the fact that siliceous sponges have occasionally under-
gone this change. The bearings of this discovery upon our investi-
gations of the lower Invertebrate fossils are very wide indeed, and I
can only point out here that in the absence of direct evidence, we
must rely, in doubtful cases, upon the condition of fossilization ex-
hibited by associated fossils, the original nature and constitution of
which is beyond doubt. If we take, for example, the singular and
problematical fossils grouped together at present under the name of
Stromatopora, which I have had especial occasion to study, we find
that some specimens exhibit a skeleton of flint, whilst others show
one of lime; and the question, therefore, arises, whether the siliceous
or the calcareous skeleton is really the original one? We find, how-
ever,—at least this is my experience,—that the siliceous specimens of
Stromatopora occur in deposits in which the Brachiopods and Corals
and other organisms which were unquestionably originally calcareous,
also usually present themselves in a silicified condition. On the
other hand, in those deposits in which such calcareous fossils as the
Mollusca and Corals retain their original constitution, we find that
the Stromatopore are also calcareous. Without, therefore, questioning
Prof. Zittel’s conclusions as to the mode of preservation of the fossil
Hexactinellids, it remains certain that the question as to the originally
siliceous or calcareous constitution of any particular class of fossils
will have to be settled by an appeal to the rocks in which these
fossils occur, and cannot be decided simply by an examination of
isolated specimens in the cabinet of a collector. Moreover, without
at all doubting that Zittel has proved his case, as regards the parti-
cular fossils which he has had under examination, we cannot avoid
the conclusion that the replacement of silica by carbonate of lime
must, in the nature of things, be an unusual phenomenon, and that,
so long as we are ignorant of the precise method under which it is
effected, we are bound to suppose that all fossils which are found to
be sometimes siliceous and sometimes calcareous are really composed
of carbonate of lime, unless distinct and incontrovertible evidence to
the contrary can be adduced.

Prof. Nicholson—Progress in Paleontology. @

The Protozoan Group of the Radiolaria has been recently shown
to have a much wider range in time than had been previously
imagined, examples of it having been lately detected in the Carboni-
ferous Limestone of Cheshire. These old types are apparently
identical with the existing Polycystina, and their tests are siliceous.
We must not, however, altogether lose sight of the possibility,
though a very remote one, that these siliceous shells were primitively
calcareous, and that they have simply undergone silicification. If
this were really the case, we should have to believe that there
existed in the Carboniferous seas a group of Rhizopods possessing
shells similar to those of the recent Polycystina in shape, but
composed of lime instead of flint.

As regards the fossil forms of Foraminifera our knowledge has
been greatly increased of late years by the researches of H. B.
Brady, Rupert Jones, Terquem, Hantken, and other well-known
workers in this difficult field. Unquestionably the most important
accession to the literature of this subject is Mr. Brady’s masterly
“Monograph of Carboniferous and Permian Foraminifera (the genus
Fusulina excepted),” published in 1876 by the Paleontographical
Society. Among special discoveries in this department the first
place must be accorded to the detection by Mr. Brady of the living
arenaceous genus Saccammina in the Carboniferous, and to the
discovery by the same distinguished observer that the pre-eminently
Tertiary family of the Nummulinida is represented in deposits as old
as the Carboniferous by no less than three generic types (Archediscus,
Amphistegina, and Nummulina itself).

Much light has recently been thrown upon the structure and
affinities of many of the fossil corals, not only by the extension to
this puzzling group of petrefactions of the microscopic methods of
research, but also by late zoological discoveries. Thus, Mr. Moseley
has shown that the great reef-building genus Millepora, so abundant
at the present day, and extending backwards into the Tertiary period,
is truly referable to the class Hydrozoa, and not to the Actinozoa, in
which it had been previously placed; whilst the genus Stylaster and
its allies are also truly Hydrozoal. We are thus introduced to a new
subclass of Hydrozoa—the Aydrocoralline —which possessed the
power of building up a calcareous skeleton, and we may expect to
find that these coralligenous Hydrozoa have played a more important
part in past time than has hitherto been suspected. Again, Mr.
Moseley has demonstrated that the living genus Heliopora, formerly
placed with the Zoantharian division of Actinozoa, in the old group
of “Tabulate Corals,” is really a genuine Alcyonarian, and is there-
fore truly most nearly related to the living Red Coral, Sea Shrubs,
Organ-pipe Corals, etc. This important discovery at once shows us
the true position of a number of ancient types of Corals, such as
Heliolites, Plasmopora, Polytremacis, etc., which are fundamentally
most closely allied to Heliopora. Thus the Alcyonaria, previously
unknown in deposits older than the Secondary, are shown to have
commenced their existence at any rate in the Lower Silurian period.

The discoveries just referred to, in fact, together with the parallel

8 Prof. Nicholson—Progress in Paleontology.

investigations of palzontologists themselves, have greatly modified
our conceptions of the old order “ Tabulata,” and, in the opinion of
some, have fairly abolished this division. With the removal of
Millepora to the Hydrozoa, and of Heliopora and its allies to the
Alcyonaria, along with the discovery by Verrill that Pocillopora is a
true Perforate Coral, the group of the Tabulate Corals has under-
gone serious mutilation, and it remains for future researches to show
whether it can be retained as a separate division of the Zoantharia.
In the meanwhile, it may be best retained for various ancient types
of Corals which cannot at present be definitely referred to other
sections (Favosites ? Chetetes? Syringopora, Halysites, etc.).

The proposal of the late Prof. Louis Agassiz, adopted by many
American paleontologists and zoologists, to remove the whole of the
great group of the Rugose Corals to the Hydrozoa, is not, in my
opinion, supported by sufficient evidence, and is contradicted by
many considerations of great weight. Judging both from the
structure of the extinct forms, and also from that of the aberrant
living genus Hdwardsia, it seems best in the meanwhile to regard
the Rugosa as standing between the two great sections of the
Zoantharian and the Alcyonarian Actinozoa.

Amongst the Echinoderms, one of the most noticeable points of
progress is the light which has been thrown upon the structure of
the strange and ancient group of the Perischoechinide by the dis-
covery of the living flexible Echinoids, Asthenosoma or Calveria,
and Phormosoma. Not only do we now know that old forms of
these singular types existed in the Secondary period (the Hchino-
thuria of the Cretaceous); but we further know that some of the
still older Paleeozoic Perischoechinide were furnished with imbri-
cated plates, this structure communicating to the test a considerable
amount of flexibility. Another point of interest as concerning this
order is the establishment (through the labours of Wyville Thomson,
Rofe, Billings, Wachsmuth, ete.) of the fact that the mouth of the
Palzocrinoids was concealed beneath the perisome, entirely hidden
from external inspection, and that the so-called “proboscis” was
truly an excrementitious aperture.

The remaining groups of Invertebrates I must pass over with very
scant notice, though our knowledge of their fossil representatives has
been immensely increased in various directions in late years, and in
some cases very interesting discoveries have been brought to light.
Among the Annulosa, the most noticeable point is the gradual exten-
sion of our knowledge concerning the air-breathing Arthropods—the
drachuda, Myriapoda, and Insecta—of the Carboniferous period.
To this, as usual, that indefatigable investigator, Mr. Henry Wood-
ward, has largely contributed. Among the lower Mollusca, con-
siderable additions have been made to our knowledge. Many new
forms of Polyzoa have been described, and Prof. Young and Mr.
John Young have shown us, in their investigation of Rhabdomeson,
how much light may be thrown upon the structure of these minute
and puzzling fossils by.the method of examination by means of
thin sections. Mr. R. Htheridge, jun., has made the curious dis-

Prof. Nicholson—Progress in Paleontology. 9

covery as regards the Brachiopoda that a small Carboniferous
species of Producta was in the habit of attaching itself firmly to
foreign bodies by means of the spines of the ventral valve. In this
department, also, Mr. Davidson still continues to publish the series
of supplements which will at last complete his magnificent ‘‘ Mono-
graph of the British Fossil Brachiopoda.”

The proposal has recently been made, and has met with the
approbation of many eminent zoologists, to remove the groups
of the Polyzoa and the Brachiopoda to the group “ Vermes,” and to
place them in the neighbourhood of the Annelida. The grounds
upon which this step is advocated are derived wholly from the
study of living forms, and, indeed, are principally based upon the
similarity observed in the developmental processes of these animals.
This change, however, is hardly likely to be accepted save by
those who believe that Embryology is the real key to classification,
and it certainly is not at present supported by any evidence afforded
by the study of the fossil forms of Polyzoa and Brachiopoda.

As regards the higher Mollusca, an immense mass of valuable
material has been accumulated in recent years by the efforts of many
patient and able observers. It would take up too much time, were
I to attempt to enumerate even the more important contributions
which have been made within the last decade to this department of
paleontology. I cannot, however, forbear a passing allusion to the
great work on the ‘Invertebrate Cretaceous and Tertiary Fossils of
the Upper Missouri Country,” published last year by Professor
Meek—a work which is not only in itself one of the most important
contributions ever made to the history of the fossil Mollusca, but the
appearance of which was followed, almost immediately, by the
lamented death of its distinguished writer.

Passing on to the Vertebrates, we may notice the important light
which has been thrown upon the past history of Fishes, by the dis-
covery of two living species of Ceratodus in the rivers of Queens-
land. . From this discovery we are enabled to speak with certainty
as to the structure and affinities of the Ceratodi of the Trias, upon
which Agassiz originally founded the genus, and which were only
known by their curious dental plates. We are further enabled to
vastly extend backwards the range of the Dipnoous Fishes in time,
for this order, formerly believed not to occur in a fossil condition, is
probably represented by the Ctenodus of the Carboniferous and the
Dipterus of the Devonian, and it seems not unlikely that others of
the so-called *‘Ganoids” of the Paleozoic period will ultimately
turn out to be truly referable to the Dipnoi.

As regards the Amphibia, large accessions have been made to our
knowledge of the Labyrinthodontia, chiefly through the researches
of Cope, Miall, Atthey, ete. The first named of these observers
has, in particular, described a large number of new and interesting
forms of this extinct group from the Coal-measures of Ohio, de-
scriptions and figures of which are to be found in the second volume
of the Paleontology of Ohio. I may also add that we seem now in
possession of sufficient evidence to justify us in asserting that

10 Prof. Nicholson—Progress in Paleontology.

the true Salamandroids (Urodela) existed in deposits at least as
old as the Permian. Not only has Geinitz given the name of
Palgosiren to a fossil from the Permian which he believes to be the
remains of a Salamandroid, but Gaudry assigns the same position to
the Permian fossils which he has recently described under the name
of Salamandrella; and the last-mentioned paleontologist is inclined
to believe that the Carboniferous genera Raniceps and Apateon are
really Urodelans and not Labyrinthodonts.

As regards the Reptiles, the researches of Marsh and Cope have
thrown much lhght upon the structure and affinities of the Mosasau-
roids and the Deinosaurs ; and the view that the latter are related to
the Struthious birds has been considerably strengthened by the new
evidence which has been obtained. Another addition to our know-
ledge of the fossil Reptiles has been made by Prof. Marsh, who has
discovered in the Cretaceous deposits of North America the remains
of colossal Pterosaurs, closely resembling the Pterodactyles proper,
but having the jaws destitute of teeth. The jaws must have been,
in all probability, sheathed in horn, so as to resemble the bill of
birds; and it is singular that there should have coexisted in
Western North America toothless flying reptiles and toothed birds—
an association which is not likely to be without its significance.
Marsh proposes to elevate these edentulous Pterosaurs to the
rank of a distinct order, under the name of Pteranodontia. Professor
Owen, again, to whom fossil herpetology already owes such an
immense debt, has founded the new order Theriodontia, for the re-
ception of a number of carnivorous reptiles from deposits of Triassic
or Permian age. The reptiles in question, of which Cynodraco is the
type-genus, show some curious affinities to the Carnivora amongst the
Mammals, as is more particularly marked by the fact that the teeth
are in three distinct sets—viz. incisors, canines, and molars—and
that the canines are very large and pointed. The Theriodonts
thus differ from all other known reptiles, living or extinct, in their
dentition, and they are also peculiar in the fact that the humerus is
provided, as in various mammals, with a ‘ supra-condyloid foramen.’

Amongst the Birds there are two specially interesting discoveries
to record, one of these being, perhaps, the most important addition
to our knowledge of the structure of fossil birds which has been
made since the discovery of Archeopteryx. I allude to the discovery
by Marsh of the curious toothed birds of the Cretaceous deposits of
North America. These extraordinary birds are so aberrant in their
characters that they have been rightly raised by their distinguished
discoverer to the rank of a distinct subclass (Odontornithes), com-
prising the two orders of the Odontolee and Odontotorme. In the first
of these orders we have only the marvellous Hesperornis, a huge
diving-bird, standing between five and six feet high, and having its
jaws furnished with numerous conical recurved teeth sunk in a deep
continuous groove, the front of the upper jaw being alone edentulous.
The breast-bone is destitute of a keel, and the wings are quite rudi-
mentary, so that Hesperornis must have been entirely incapable of
flight. On the other hand, it must have been an admirable swimmer

Prof. Nicholson—Progress in Paleontology. 11

and diver, and it probably lived upon fish, which it captured by
means of its toothed jaws. Its tail was not long and lizard-like, as
in Archeopteryz, but consists of about twelve vertebrae, of which
the last three or four are amalgamated to form a flat terminal mass,
there being at the same time clear indications that the tail was
capable of up-and-down movement.in a vertical plane, this probably
fitting it to serve as a swimming paddle or rudder. The vertebree
of the cervical and dorsal regions are of the ordinary well-known
ornithic type.

In the Odontotorme — the second order of Odontornithes— the
type-genus is the wonderful Ichthyornis, which, though apparently
aquatic in its habits, differed from Hesperornis in having well-
developed wings, constructed upon the usual ornithic type. The
jaws were furnished with compressed pointed teeth, which were
sunk in distinct sockets. The vertebree, further, have the absolutely
unique character—a character unknown in the entire class Aves—
that their bodies were bi-concave. In this respect, therefore, Ichthy-
ornis makes an approach to the Fishes, Amphibians, and Reptiles, in
which amphicoelous vertebree are common, or occur in certain groups.
The tail of Ichthyornis, as of the allied Apatornis, is unfortunately not
known.

The second discovery among Birds to which allusion ought to be
made is that of the Odontopteryx toliapicus of the London Clay, de-
scribed by Prof. Owen. This very singular bird exhibits the peculi-
arity that the osseous margins of the jaws are prolonged into tooth-
like extensions, which are of two sizes, and which were probably
encased in prolongations of the horny substance of the bill. These
processes are triangular, compressed, and directed forwards, and
they are not to be confounded on the one hand with the denticula-
tions found in the horny sheath of the bill of various living birds,
or on the other hand with the genuine teeth possessed by the
Odontornithes. Professor Owen concludes that Odontopteryx was
probably aquatic in its habits, and he regards it as a natatorial bird
allied to the Anatide.

Coming, finally, to the Mammals, the discoveries which have been
made within the last few years, more particularly those which have
resulted from the researches carried on by Marsh, Leidy, and Cope
into the Tertiary Mammals of North America, have been so numerous
and so important, that my time to-night will not permit me to do
more than simply to allude to a few of the more important ones,
and more particularly to those by which changes have been effected
in the previously existing systematic arrangement of the Mammalia,
or which have fundamentally altered our conceptions of the character
of certain groups.

Among the Monotremes, Krefft records a gigantic Echidna from
the Post-Tertiary deposits of Australia. As regards Marsupials, I
may merely mention the recent appearance of Prof. Owen’s magnifi-
cent work on the Fossil Mammals of Australia, in which will be
found the fullest record extant of all that is known as to the wonderful
extinct Marsupials which ranged over Australia in Post-Tertiary
times.

12 Prof. Nicholson—Progress in Paleontology.

The great order of the Ungulates has of late years been vastly
added to by the discovery of entirely new forms, or of specimens
more fully elucidating the structure of previously known forms. I
can only advert to one or two points in this connexion. One of
the most striking of Marsh’s many discoveries is that of the two-
horned Rhinoceros to which he gives the name of Diceratherium.
This remarkable form is from the Miocene of Oregon; it differs
from all the known two-horned Rhinoceroses in the fact that the two
horns are placed transversely and symmetrically upon the nasal
bones. In this respect, indeed, the genus differs from the whole
group of the Perissodactyle Ungulates. Another discovery by Marsh
is that Coryphodon, which is found in the Hocene of both Europe and
America, though essentially Perissodactyle, possesses five toes to the
foot, and thus differs from all other known Ungulates except Oro-
hippus. Of the extraordinary series of forms by means of which the
living genus Equus is connected with the Eocene Hohippus and Oro-
hippus I need scarcely remind you, as the principal facts in this
connexion are now widely known. © Another, though less complete,
series of connected forms is now known by which the genus Dicotyles
is linked on to the Eocene Hohyus; and a third series exists by
which the aberrant Camelide of to-day can be traced back to forms
which agree with the typical Ungulates in having a full series of
incisor teeth (e.g. Poébrotherium and Protolabis).

Allied to the Ungulates in many respects, and forming a group
intermediate between them and the Proboscideans, are the large
Kocene Mammals which Marsh has raised to the rank of a distinct
order under the name of Dinocerata. The fore-feet are five-toed,
and the limbs are like those of the Hlephants; but the most
remarkable characters of these animals are those of the cranium.
As regards the dentition, the upper jaw is destitute of incisors, but
there is a pair of huge tusk-like canines, directed downwards, and
there are six small molars on each side. In the lower jaw are six
incisors, small canines, and twelve molars and premolars. The
armature of the head is also very peculiar. The upper jawbones
carried each a pair of small processes, probably of the nature of
horn-cores; the nasals carried two similar but smaller cores; and
the frontals are developed into two larger bony processes apparently
also intended to be sheathed in horn. ‘There were thus three pairs
of horns, similar in structure to those of the hollow-horned Rumi-
nants. There does not appear to have been any proboscis, and the
brain was proportionately smaller than in any known Mammal,
either living or extinct, and even smaller than in some Reptiles.
We cannot, therefore, credit Dinoceras with the possession of a large
amount of intelligence.

Another remarkable group of Kocene Mammals has been raised to
the rank of a distinct order under the name of Tillodontia. These
animals possess a curious combination of the characters of the Car-
nivora, Ungulata, and Rodentia. The general form of the skeleton
most closely resembles that of the Carnivores, the skull being in
many respects similar to that of the Bears, while the feet are five-
toed, with the whole sole applied to the ground, and having ungual

Ceol Mat 1878

New Series Dacadel

que PIEXIRINE Thou g

Yaambers Heal.

Bridlington

BY Bort Druin

REFERENCE TO MAP

Sa Recartheds, Marsh, Bat 5
8 The Heasle bats
The Fox Gravel.
EQ he Pople Clay without chalh
Se Ditto with halk.
me Whe Great Chalky Clay.
g Escarpmt of the Chatk.
€ Diflo of the Oolite .
NB.The Grunt Chalky Clay has occasionally 1 ed of
awel in or under ib. Gravel: vid Srud alse occour
wrutically errr the Unchuded parts of the Map

The phaices of name: of there are istdicaled . Gravel
ame ns J to 10 are aritiret

1 GOAST SECTION. Fron the Humber to Flambero’ Head
|

Kilnsea Beacon Dimlington Cliff

Athan seam Fvand costly packed with Mica Celvcldice
and ctherMollusca than. undisturbed stale escurs here in beet ct

Sand.le Mere Hilstor, (nian) Ringborv’(tndand)
(Lacustrine Bed expooed allow water) f

; _ 4 7 Hor
Prechwalter Mollusca

a Cate) Latbot Hotel
Cli euch concealea by talius

Sette of HarBurn

lore. Sane

Bridlington Quay
| The ‘shell bed here shen now covered by Esplanade

7 rs ee eT
Fines anda ny apes See eas

( Scite of Auber
Blown Sand

Il ENLARGEMENT OF RINGBORGCUFF IV. ENLARGMENT OF HORNSEA CLIFF.

Il INTERSECTION OF THE SUBCKETACEOUS OUTCROP

Bucton Clit Spector. CUP
ig 4 great slp here conceals the outerop
Provable fixul?

f :
VI-ENLARGEMENT OF HESSLE QUARRY SECTION
. VHESSLE cuTTING. . Hecal nigh ibaa a Vill. KELSEY HILL PIT (IN 1867). Ik. CLEETHORPE i a ie a
Lovorrupinat He MONEE RD). el rent nda aera curr. as Mark Beriby
ttl 2Sands with slight traces Grave. . Sete onber(ortune®) tetiDoy fi
he sueaiaial, J Flr of Repplemarked day. | , eee ia
+ path brekhiamithMam' tones. ° z |e emai ve P= -
ch : ne ne = Es

cHurple lay with rounervus rock boulders «nil closely packed: with the debris of lormeticns

Norfolk Sections). b Beds of dark sand and bands of a and c
c'Beils of sand in ¢,one of which, al Bridlington, yeilded. the Britlington nv Uleusca. Buk ts
L - fox coloured with

REFERERENCE TO SECTIONS ImX. (;LAcrAL BEDS alod, viz? aThe Great Chalky Clay full of rolled Chalk dchris (440 of th
older than the Chalk, ub with he Chalk debris in subordinate quantiby only and prussing up trto, hd. Chay withless débris of any kind and in which the Chalk dBris disappewe

concealed by an extension of he Biplanade. CMoraines of rolled. Chalk co-eval with ¢ andwith bands of ¢ and. sand beds xx inthem.. a’ Beds of sand and grard ind. pos gLACALBkDS ¢ wh, vist ethe Hessle sand and gravel The Hassle Clay
Gg Pdached patche vere,

bluish vertical, partings and containing subangular chalk fragments, many small boulders (mostly rounded, Land, occastonally angular tee-groeved blocks. 9 Sand. and. gravel posterior to the Hes: sle clay , the sands having included beds of Gravel g'.

Marts, 1. Upper Oolite . 2Neocomian .3 The Red. Chalk 4: White Chalk. The dotted line denotes oppreximately the position of the Chalk Floor

ef simlar age, h Gravel composed chicly of ror Ratlenedl fragments w chalk. ( Valley. Grawls,sone with treshovater mollusca . Recent Cycle

SECTIONS XI, Kil, Kill, XIV, AND XVI SHEW THE POSITION OF THE BEOS RELATIVELY TO THE CHALK,AND OOLITIC ESCARPMENTS.
SECT. XII

Uleedy Grange

SECT.xI.
Thevintor Stu's ee SECT.XII a y Gr
Blyton Kirloy ree Thornton Sta! Helen Sproatley Clif NoF Talbot Rand TheTorringtons Sipchills ThempeleMi Wel Newton Hotton le Clay cleewowpie Clift Dinlingn cif —Mininaty Ma Sage lee
} lumber, | | | | | yl, ¢: = ——
: ro ) : 1 amber} | | | | | . |) acter | |g ata eat Sees
Q
SEGT.XIV. SECT. XVI
: P SECT. XV. SHEWING THE POSITION OF THE FEN GRAVEL. knell
Kscarp Rehan tr Lanawecth Riv Pan, Marcham Lusby piv Se Wiltor rey arth Ki e leapang Ballinger Hemningsby Mouse Wiidale Tee Scrunll Ganka
Silla eqiham. HirTangreeth at forcaathe as iy RinSteping Seruby Wilton 4 ry Mink Kyme ZirkyMor, ringtone Marcha Sepag) eta ee
| a | The Fer | The Fen | | RirRadn | ¢
é = I a x :
REFERERENCE TO SECTIONS xi To xvi, a Tias, bTaas. clower Colite. doMildle and Upper Oolite. ¢Néocemian. F Red Chalk. g White Chath 1 The Great Chaiky Clay (a of the prerious sections) 2 he Purple Clay (of the previous secteans) 3 sale Clay (1 of the )

WWat DO pheeo Lah

ne Pia Gravel. NAAM sunds and gourds except the Fen gravel omitted

es

etiam Ea

=

S. V. Wood, jun.— American and British Surface-Geology. 13

phalanges similar to those of the Urside. The premolars and
molars, on the other hand, have grinding crowns, the canines are
small, and there are two incisors in each jaw, which agree with
those of the Rodents in being of large size, in having chisel-shaped
crowns, and in springing from persistent pulps.

One other discovery, also made by Marsh, I must just mention,
and then I have done. The eminent paleontologist just alluded to
has shown that the Lower Hocene of New Mexico and the Middle
Eocene of the West contain a number of Lemuroid genera, higher
in type than the existing Lemurs, but decidedly inferior to the
Catarhine monkeys. The most remarkable point about the two prin-
cipal genera of early Lemuroids—viz. Lemuravus and Limnotherium
—is their generalized. character. This is especially seen in the
dentition, Lemuravus having no less than forty-four teeth, arranged
in a continuous series, and Limnotherium having forty teeth.

I have now endeavoured to lay before you a brief account of some
of the leading results which have been effected by the researches of
paleontologists during the last few years. The field we have
traversed is a wide one, and there are many parts of it which it
would have amply repaid us to have considered in detail. I need
hardly add, also, that I have been compelled by the exigencies of
time to forbear altogether from even an allusion to many important
accessions to our knowledge. One of the objects of this address will,
however, have been gained if I have succeeded in convincing you
that the Science of Paleontology is in a sound and healthy condition
not yet arrived at maturity, but growing actively, and likely to grow
in the future. This ought to be the more satisfactory to us, as we
may feel quite sure that it is to Paleontology, perhaps more than to
any other Science, that we may look for the key to some most inter-
esting and important theoretical problems in Biology.

'JJ.—Amertoan “ Surrace Gronoey,” anp its Retatton To Britisu.
With somE REMARKS ON THE GLACIAL ConpITIons In Britain,
ESPECIALLY IN REFERENCE TO THE “GREAT Ick AGE” or Mr.
JAMES GUEIKIE.

By Szarztes V. Woop, Jun., F.G.S.

(PART III.)
(Illustrated by a large folding Map and Sections. Plate I.)
(Concluded from Dec. II. Vol. LV. page 551.)

HAVH, in the foregoing, endeavoured to set out the general con-
ditions under which that one principal Glacial deposit of England
which I term “Upper Glacial” was accumulated, according to
the views to which I have been led by several years’ active exami-
nation of the area occupied by it, and a still longer study of the
phenomena observed. ‘They differ materially in many respects from
the views urged by Mr. Jas. Geikie in his “Great Ice Age,” and
continued observation will help to determine which can best be
reconciled with the facts; but before leaving the subject of this
formation, I must observe that the diagram and description by Mr.

Skertchly of the manner in which Lincolnshire was glaciated, as

14 8. V. Wood, jun.—American and British Surface- Geology.

imported by Mr. Geikie into his book, conveys what I regard as an
erroneous view.

According to that diagram! and description, the morainic material
is represented as having been derived from ice moving from N.E. to
S.W., that is to say, from the coast inland, and transversely to the
strike of the formations from which its moraine was derived; in
fact, from the direction of Scandinavia. The moraine alsb is re-
presented as though it extended over the Chalk Wold, and the whole
of it had come from N.H. to $8.W. by a process of push or overlap,
extending a little way only however, and not so as to prevent the
morainic material being mainly identical with the formation on
which it rests. These things do not, in my experience, accord with
the facts. With the exception of the part to which I have already
adverted near Flamborough Head, and the mouth of the Pickering
glacier-trough, and some very small patches elsewhere (one of which
is on very high ground at Huggate), the Chalk Wold is destitute of
Glacial clay of any kind, both in Yorkshire and Lincolnshire.
Where it abuts against the western side of the Lincolnshire Wold,
the morainic material certainly assumes its most chalky aspect,
becoming little else than reconstructed Chalk, but its path has
been mainly parallel and not transverse to the Wold. This would
have been seen if a map which I drew of the Glacial and Hessle
beds over Lincolnshire and South-east Yorkshire (and which accom-
panied the author’s private copies of the Memoir by Mr. Rome and
myself) had been allowed to appear in the Journ. of the Geol. Soc.
To remedy that defect, and to render the views discussed in the
present paper more intelligible, I have given by photo-lithography
a plate which contains a map of South-east Yorkshire and most of
Lincolnshire, with the sections in illustration of it, which formed
one of several that I some years since prepared for a work on the
later Geology of Hast Anglia, which I contemplated, but which
failure of health and other reasons made me relinquish.

From this map it will be seen that the moraine to which the
chalky clay of East Anglia owes its origin (and which is indicated
on it by the black shading with white dots) streamed down from
the north-west in the great trough between the Chalk and the
Oolitic escarpments of Lincolnshire : from whence expanding south-
wards it spread over the Hastern and East Midland counties. Its
northerly diminution and eventual cessation some way south of the
Humber shows, I consider, that the morainic chalky clay is not in
the position in which it was generated beneath the ice, as Mr.
Skertchly’s diagram assumes, but that most of it has travelled and
been deposited far from its place of origin; while its absence to the
west of the Yorkshire Wold is altogether repugnant to that motion
from the coast inland, upon which in the case of Lincolnshire Mr.
Skertchly insists. Between Castor in North Lincolnshire and a
point a few miles south of York, Mr. Rome and I could find no

1 Great Ice Age, p. 358. The diagram itself appears to be an application to the
case of Lincolnshire of the one given by Mr. Tiddeman in illustration of the
formation of Till in North Lancashire and the adjacent country, in the 28th
volume of the Quart. Journ. of the Geol. Soc. p. 481.

S. V. Wood, jun— American and British Surface-Geology. 15

trace either of it or of any other kind of Glacial clay, and unless it
be concealed beneath the marshes of the Ancholme and those on the
north of the Humber, there does not appear to be any glacial clay
between those limits, though there is some sand and gravel ;’ but
near York another great sheet of Glacial clay (destitute entirely of
chalk and sometimes destitute of boulders) begins, and, capped in its
lower elevations by the Hessle beds, extends uninterruptedly
northwards through the great vale which lies between the Pennine
Hills on the west and the Howardians and Eastern Moorlands on
the east, and is continued through Durham and Northumberland.
This sheet represents in my view the material produced by the
glacier-ice after this had shrunk back through the Vale of Pickering
and the Humber, and deserted the chalk country and the Lincoln-
shire troughs; and it is, I consider, of the same age as that which,
lying north of the Wolds and extending along the maritime border
of Durham and Northumberland, succeeded the purple clay of
Holderness. Looking at the distribution of the chalky clay thus
shown on the map, and at the character of the chalky clay which
forms the basement portion of the thick mass of which South-east
Holderness is made up, it is clear, I think, that the moraine en-
gendered north of Castor (except such as went northwards round the
angle of the Wolds and through the Pickering trough), travelled
out through the gorge of the Humber to form this basement clay of
Holderness, which teems with rolled chalk and is also largely
made up of the spoil of the clays which intervene between the
Trias and the Chalk; and that the moraine which makes up the
extensive clay deposit of the Eastern and Hast Midland counties has
been almost entirely generated south of the Humber and north of
the southern edge of the Fenland.

By the motion of this land-ice down Lincolnshire from north-
west to south-east along the side of the Wold, the moraine
necessarily corresponds there ina great degree with the formations
on which it rests, and from which it was derived. From the motion
too of the ice being from the higher ground to the lower, simul-
taneously with and independently of the general southerly and south-
easterly motion of the whole mass, the debris degraded from the Wold
travelled off it into the trough on its south-western side to form part
of the great stream of intermixed morainic matter which, passing
down this trough, spread over the Eastern and Hast Midland counties.
By such motion of the ice, the moraine of pure Chalk which resulted
from the degradation of the Wold does in some places overlie and
overlap that produced from the degradation of the Jurassic clays,
though by no means in that general way which Mr. Skertchly’s
diagram would imply; and this motion will explain how Mr.
Skertchly’s observations, being directed to the southern extremity of

1 There is some thin clay over the Permian north of Doncaster, but whether this
is referable to the Glacial or to the Hessle clay I am unable to say. There is also
much sand, which is partly capped by clay, between Retford and Doncaster, but these
are to the west of the line reterred to in the text. Beds of sand and gravel also cap
the Liassic and Oolitic escarpments of the extreme N.W. of Lincolnshire. These

were called by Mr. Rome and myself “‘ Denudation sands,” but they may possibly
represent the purple clay.

16 8S. V. Wood, jun.— American and British Surface- Geology.

Lincolnshire, and to the Fen and other country adjoining it, have, I
think, led him to the views which he expresses by his diagram and
description. I should, however, have thought that it would have
occurred to him that such material as that of which the chalky clay
of the Hastern counties is composed, comprising as it does the debris
in abundance of all rocks from the Chalk to the Lias, and extending
in one direction to the coast of Suffolk, and in another to the brow
of the Thames Valley, could not have resulted from the action
he represents. Had it done so, instead of consisting of the large
proportion of Jurassic debris that it does, we ought to find a belt of
it on the north-east side of these counties formed of Crag and
Eocene debris only, succeeded south-westwards by one of Hocene
and Chalk debris only, and on the west of those counties by one of
Chalk only, all of them free from Jurassic debris of any kind; but, as is
well known, nothing of the sort exists. Similarly, also, had this N.H.
to §.W., or Scandinavian direction of the moraine prevailed over the
Wold, the western side of some of its northern or Yorkshire portion
should have been flanked with a similar mass of reconstructed chalk
to that which flanks its southern or Lincolnshire extremity; but none
of it is so, though there is an abundance of flint gravel there, which
I consider belongs to a later date—that of the Hessle-beds probably.

So far from ice moving from Scandinavia having had any part in
the glaciation of Britain, I can discover no evidence either of the
action or influence of any other ice than that which descended from
British mountains ; and notwithstanding all that has been urged by
Dr. Croll or Mr. J. Geikie to the contrary, 1 contend that no ice
extraneous to Britain had any part in its glaciation; and that
throughout the Glacial period open sea existed between Britain and
Scandinavia, though at or after the close of it the southern portion
of the North Sea between Hngland and Holland became converted
into land.

Having dealt with what appear to be the formations attending
the inception, culmination, and wane of the major glaciation or true
Glacial period, I now come to the formations immediately antecedent
to, and those synchronous with, and succeeding the minor glaciation;
that is to say, to the formations of the post-Glacial period.

ENGLISH. | Sr. Lawrence Basin.

The forest surface and
its associated beds with
great mammalia that
rest on the Erie clay.
The beds 3a which over-

The series of beds posterior to the general emergence
of England. ‘This series includes the Hessle beds and
their equivalents of the north-east ; and the Middle sand
and Upper Boulder (Brick) clay, their equivalents in the
north-west. Also the mud-bed of Selsea and its over-

lying gravel with great erratics. Also the river-grayels
and brick-earths with Paleolithic implements, some of
which are of much earlier origin than others. During
the formation of the beds of this series, especially of the
older part of it, great changes were taking place in the
distribution of land and sea over England, due to the
continuation of the disturbances which commenced under
the Upper Glacial sea.

lay this forest surface.
The marine clays of the
Lower St. Lawrence.
The terrace formation of
Ohio (beds No. 4) and
the Kames and Hskers
of the Canadian High-
lands.

S. V. Wood, jun American and British Surface-Geology. 17

Part of the beds of the St. Lawrence basin above tabulated with
the English beds posterior to the general emergence, have already
been tabulated beside the English’ Middle and Upper Glacial; but
having given my reasons for thinking it probable that they may not
be synchronous with these, but be posterior to the major glaciation,
I have now placed them in the position of synchronism to which
the probabilities seem to point.

In the American portion of the deposits thus tabulated, the first,
or forest beds, seem to me, if in situ, to have been formed during that
temperate period which, following the elevation of England from the
chief part of its general submergence, was accompanied there by
the reintroduction of the great mammalia, and succeeded by the
minor glaciation. The beds 3a appear to me to mark the culmi-
nation of this minor glaciation when the dissolution of the glacier
which rested on the Canadian Highlands filled the lake-basin with
freshwater, over which berg and other ice floated. The marine
clays of the Lower St. Lawrence and Atlantic coast seem to me to
belong to the same period, when in Lower Canada the glacier-ice
terminated in the sea-water of the Gulf of St. Lawrence, and to
have accumulated in the sea which followed the recession of the ice
until the area they occupy was raised above its level.

The Eskers and Kames of the Canadian Highlands seem to me to
mark the wane of this minor glaciation, and to represent the moraine
of the ice after it had ceased to reach the sea or lake-waters; while
the successive terraces formed by the beds No. 4 indicate the suc-
cessive falls in the water of the lake-basin, as the ice of this minor
glaciation wasted out of the narrow throat of the St. Lawrence
valley, and so allowed the waters to escape from the lake-basin into
the Gulf of St. Lawrence.

As already observed, the Mississippi Bluff formation appears to
have been in progress throughout both the Glacial and post-Glacial
periods, that is, throughout the major and minor glaciations.

In the English part of the deposits last tabulated, there has long
seemed to me to have been one return of cold after the country had
emerged from the depression at the end of which the Moel Tryfaen
sands were formed, and had become stocked with the great mammalia.

In describing the beds of South-east Yorkshire and Lincolnshire,
in the year 1867,‘ Mr. Rome and I distinguished those which ap-
peared to us of Glacial age from certain others which, overlying
these, were unconformable to and overlapped them in the direction
of the Chalk Wold. These overlying and overlapping beds we
called the ‘“‘ Hessle,” and referred to the post-Glacial period, i.e. to a
time posterior to the general emergence of the country from its
great depression and glaciation. These beds, consisting of a fos-
siliferous sand and gravel confined to low elevations, and of a clay
with boulders (mostly very small, but occasionally of larger dimen-
sions), and other debris overlying it, and reaching to higher
elevations than the gravel, we subsequently to the publication
of our paper traced to the borders of Durham; and, in the case of

1 Quart. Journ. Geol. Soc. vol. xxiv. p. 146.
DECADE II.—YOL. V.—NO. I. 2

18 S.V. Wood, jun.— American and British Surface- Geology.

the clay, up to elevations exceeding 300 feet in the Eastern Moor-
lands of Yorkshire. From information, also, given me by Mr.
Topley of the Geological Survey, the same beds appear to be re-
presented partly in the form of an upper clay with boulders, and
partly in the form of gravels that have derived their debris from the
Cheviots, which occur over the lower elevations of Northumberland,
i.e. over the plateau country which forms the eastern portion of that
county; and in all probability they extend into Scotland. Similar
beds in the form of a (so-called) Middle Sand and Upper Boulder
(Brick) clay with occasional boulders extend over the lower ground
intervening between the Pennine chain and the coast in Cumberland,
Lancashire, and Cheshire; and they reach along the north-west
coast as far south at least as the north of Carnarvonshire. Prob-
ably also the sands and clays of the Severn Valley containing marine
mollusca of similar recent character to those found in the Hessle
and Fen gravels, and in the upper clay and middle sand of the
north-west, which have been described by Mr. Maw (and the shells
of which he kindly sent me for examination), belong to the same
period. The southern limit of the Hessle clay appears to be at
Firsby, on the northern edge of the Lincolnshire Fen; and, so far
as I know it, the southern limit of the upper clay of the North-
west of England appears to be at the same latitude in the Menai
Straits, but on the eastern side the gravels of the formation carry
the submergence a little further south, viz. over the Cambridgeshire
Fen."

On both sides of England, therefore, a similar degree of re-
frigeration and limited submergence, giving rise to these beds,
seems to have occurred; this submergence (not the glaciation)
shading off southwards to evanescence on the eastern side be-
tween lat. 52° and 53°; but on the west it may have extended
further. The gravels of this formation, which in the Cambridge-
shire Fen extend southwards to about lat. 52° 30’, are there and
over the Fen northwards uncovered by Boulder-clay,? but in
Holderness they are so covered. The marine molluscan fauna of
these gravels differs in character from that of the Hast Anglian
Glacial beds, in that it contains none but species which live either
in British seas or in the seas immediately north of the Shetlands,
whereas the Glacial beds of Hast Anglia contain some species that
are unknown living, and others which, if living, are represented by
species not known as such nearer than the North Pacific. Inter-
mingled with the mollusca of these gravels both in Yorkshire and

1 The distribution of this (Fen) gravel along the northern edge of the Fen and
where it approaches near to the Hessle clay is shown in the map, and its position
relatively to the chalky clay in section xy.

» A stony clay, a few feet thick, which covers unconformably the Lower Glacial
formation on the Norfolk coast, between Mundesley and Eccles (lat. 52° 48’ to 52° 51’),
and which there rises to an elevation of about 40 or 50 feet above Ordnance
datum, seems to belong to this formation. The molluscan fauna of the Hessle gravel
and its equivalents in the East of England are given in the tabular list to the sup-
plemene to the “ Crag Mollusca,” in the volume of the Paleontographical Society
or 1873.

S. V. Wood, jun.— American and British Surface-Geology. 19

in the Fen district there occurs in certain localities a profusion of
the river-shell Cyrena fluminalis, which now lives in the Nile and
in the rivers of Thibet and China, and which is fossil in Italy
and other places, as well as in the gravels of the Somme, the Thames
Brick-earth, and at Barnwell near Cambridge, and which also
lived during the later Crag and earliest Glacial formations. The
presence of this shell, which seems peculiar to running water, proves
that the valleys of the lower grounds were, during the Hessle
gravel, occupied by rivers of water and not glaciers, but the valleys
of the higher and mountainous regions may at this time have been
occupied by glaciers, and, indeed, during the formation of the over-
lying Hessle clay, were, as it seems to me, so occupied. The debris
shed out by these glaciers, together with that supplied from the
coast waste of ground at lower altitudes than the mountains, such as
the Yorkshire Wolds and Moorlands, the Durham Permian terrace,
etc., appear to me to have furnished the material of this clay.

The completeness of the break between these formations of the
minor glaciation and those of the major, as well as the considerable
period covered by it, is shown partly by the way in which the
purple clay (c and d) has been removed by denudation prior to the
deposit of the Hessle beds, so that the Hessle clay wrapping over
the denuded edges rests in the valleys, which are cut through the
purple and down to the basement clay (a), on that clay itself; and
partly by the occurrence of the Cyrena in gravels of Hessle age, and
of mammalian remains in the breccia at Hessle (bed No. 4 of Sec-
tion VII.); for these furnish evidence that the interval indicated by
this break was accompanied by the introduction of a terrestrial fauna.

Mr. Thomas Jamieson, in a paper read before the Geol. Soc. of
London in 1874,' has endeavoured to show that after Britain had
arisen from its great submergence, the valleys of the Scotch High-
lands were filled with glaciers, which in some places reached to
the sea; and that to the glaciers of this period the Kame drift of
that region is due; and as I have already observed and explained
in detail while discussing the Ohio Eskers, an examination which
I made in the year 1870 of the drift of the Scotch Highlands leads
me to agree with Mr. Jamieson in this view.

We have been ftirnished with a description of the Glacial fea-
tures of the Westmorland mountain district by Mr. J. C. Ward, in
three papers read during the years 1873-4-5, and published in the
Journal of the Geol. Soc. of London (vols. xxix. xxx. and xxxi.).
Mr. Ward considers that we have evidence there of three periods ;
the first being that of confluent glaciers, or ice-sheet, the origin
of which he regards as altogether British, finding no indication of
the action of any ice-cap from the Polar regions. He also observes
that he cannot find any facts to suggest a cutting up of this period by
several mild seasons. The second period is that of submergence
and amelioration of temperature ; and the third that of a minor
glaciation which the district underwent subaérially, and in which
the glaciers were not confluent, but confined to the valleys. This

1 Quart. Journ. Geol. Soc. vol. xxx. p. 317.

20 8. V. Wood, jun. —American and British Surface- Geology.

period of minor glaciation appears to be that which we are now con-
sidering, and the only divergence between the opinion to which Mr.
Ward appears to have been led from a study of this district and
that to which I have been led by a study of the East and South of
England, consists in the submergence which he regards as having
followed the first and principal glaciation, and preceded the minor
one; my view being that the first glaciation and the submergence
were coincident, and that the sea merely took the place of so much
of the ice as was below its level, as this wasted away before amelio-
ration of climate.

In reference to this divergence of opinion I would observe that
the features displayed by the Lower Glacial series of beds in Cromer
Cliff present, as it seems to me, the clearest evidence of the increase
of submergence having taken place coincidently with the increase of
glacial conditions on the Hastern side of England up to that stage
in the Glacial period to which the Lower Glacial series of deposits
carry us—a part of the geological record, be it remembered, which
has been erased from any other part.of Britain that may once have
furnished it, but which carries us onwards from the latest Crag
deposits with no more than an insignificant break.

If, therefore, the glaciation came on in the North-west of England
without submergence, and its disappearance there was followed by
this submergence, it follows that a complete oscillation must have
occurred between the two sides of England, so that when the East
and South-east of England was rising, as it was during the later part
of the Upper Glacial formation and earlier part of the post-Glacial,
the west and north-west must have been going down; but the red
and white chalk, derived from the Lincolnshire glacier, which
generated the chalky portion of the Upper Glacial, having got into
the gravel at nearly 500 feet elevation so far west as the old strait
between Ebrington Hill and the main island of the Cotteswolds,
seems strong evidence that the submergence of the west side of
England was to this height at least contemporaneous with that
of the Hast, when this glacier terminated in the sea in the way de-
scribed in a previous part of this paper. On the other hand, it
must be admitted that the character of the marine mollusca from
the beds of the Severn Valley is so much more recent and
British than is that of the mollusca of the Hast Anglian beds, even
up to the horizon of Bridlington and Dimlington, that they can
scarcely be synchronous. This objection, however, applies equally
to the Mollusca of the Lower Boulder-clay of Lancashire, and to
that found in the Glacial clay of Yorkshire north of the Wold-scarp,
while the gravels of the South-west which contain the Lincolnshire
debris have not yielded any molluscan remains. It is not unlikely,
therefore, that after the elevation which followed the Contorted
Drift of Cromer, there set in coincidently with the further emergence
of Hast Anglia an increase of the submergence northwards and
westwards, and that this accompanied, and perhaps caused, the retreat
of the ice from Hast Anglia, while the North and North-west re-
mained enveloped by it. The giving place by the Holderness

S. V. Wood, jun.—American and British Surface- Geology. 21

Glacial clay of pure morainic origin to clay presenting the aspect
of having been due to marine deposit only, when the submergence
was great enough to cover the Wold near Flamborough to eleva-
tions of more than 400 feet, rather favours such a view; and I have
long contended that this difference in the mollusca arises from the
Lancashire and other northern clays of Glacial age having been
formed at the close of the Glacial period, when the Crag-like fauna
of the Hast Anglian Glacial beds had changed into that purely
recent and Europeo-Arctic one which occurs in these clays, and in
the Moel Tryfaen bed; up to which time the ice prevented the
accumulation of any deposit in that part of Britain.

The description given by Mr. Ward of the mounds of stratified
sand and gravel in the Lake-country, which he refers to the period
of submergence, so precisely corresponds with the Kame drift of
the Scotch Highlands, that I think they must belong to the same
class of Glacial phenomena, and not be deposits of the period of
submergence at all. Indeed, if we consider that wherever the
marine sands of the submergence period lay in the way of the
glaciers of the second glaciation, they must have been ploughed
out and destroyed, we need not wonder that the instances which
have occurred of the sands and gravels of this period, such as those
at Moel Tryfaen and near Macclesfield, should be so rare as they
are, though they are sufficient to prove the great depth of the Glacial
depression in those parts of England.| These mounds, Mr. Ward
says, are, at whatever elevation they occur, topped with erratic
blocks; and he deduces from this circumstance the inference that
the period of the gravels was a mild one, and was followed by a
colder, in which these blocks were scattered over them. Precisely
the same feature is, however, exhibited by the Scotch Highland
Kames, and the explanation of it which I adopt is different from
that of Mr. Ward, and is that as the washing out of the subglacial
moraine into gravel took place by the melting back of this non-
confluent glacier-ice subaérially, the moraine of blocks which travelled
on the surface of the glacier fell from its termination on to the
surface of the gravel-heap thus produced.

Be this, however, as it may, we appear to have in the mountain
districts of both England and Scotland precisely such a period of
minor or nonconfluent glaciation as that to which Mr. Rome and
I first, in 1867, and I in several papers subsequently (especially in
one with some detail of circumstances which appeared in the Got,
Mag. for April, 1872), drew attention as explaining the origin of

1 Ttis not, indeed, unlikely that the polished and broken fragments of shells which
occur in the gravels of some of the Welsh valleys, such as that of St. Asaph (some
of which were sent me by Prof. Hughes), and even those in the Upper Boulder-clay
and Middle Gravel of the North-western counties, of which several small collections
from Cheshire andy Lancashire have passed through my hands, got into these gravels
and clays of the Hessle period in this way; and the same remark applies to the
Caithness clay, the shells of which are promiscuously scattered through its mass, and
are of a far less Arctic character than those of Elie and Errol. The glacier which
during the minor glaciation filled the great valley of the Caledonign Canal probably

at its commencement ploughed out the marine gravels from that valley, and carried
them into the Caithness clay then in course of formation.

22 8S. V. Wood, jun.—American and British Surface- Geology.

the Hessle clay and the Upper Boulder-clay of the North-western
counties of England ; and taking into consideration the latitude and
degree of glaciation in the various parts of Britain over which the
formations of the period of minor glaciation which I have in the
foregoing description supposed to be synchronous occur, there
appears to be a general correspondence between them both in
climatal conditions, and in the recent character of the mollusca
wherever these latter are present.

Mr. Tiddeman also, whose attention has been chiefly directed to
the Lancashire mountain district, has in a paper read before the
Anthropological Institute on the 22nd May, 1877 (Nature, vol. xvi.
p- 70), expressed in precise terms his belief in there having been
a period of major glaciation, of which the evidences are most ap-
parent in the central or less northern parts of our island, and a
period of minor glaciation whose evidences are confined to those
northern parts; while Mr. J. Geikie in the second edition of his
“Great Ice Age” takes a similar view of the synchronism of the
Hessle beds, the beds of the north-west, and of the gravels of the
Highland valleys, to that which I have done; and I am gratified to
be able so far to agree with all these gentlemen.

To this same time or nearly so, and long after the warmer waters
of the Biscayan and Lusitanian coasts had at the close of the major
glaciation been separated from the colder waters of the North Sea by
the conversion of a portion of that sea into land, I have referred the
gravel with great erratics of the Sussex coast which overlies the
marine mud-bed of Selsea, first described by Mr. Godwin-Austen
(whose list of shells was largely added to by Mr. A. Bell); containing
semifossilized mollusca of southern facies all still living in South
British and Lusitanian waters, but among which are included some
that do not now range so far north as the British Channel. The
erratics of the gravel and clay which overlie this formation are
referred by Mr. Godwin-Austen to the action of coast-ice drifting
from the French side of the Channel.!

We have thus, according to my apprehension of the case, a con-
vergence of evidence to show that a well-marked interval of minor
glaciation following upon the occupation of the sea-bettom along the
Southern coast of England by a fauna indicative of water some-
what warmer than that of our present British Channel, of our rivers
by the Cyrena fluminalis, and of the land by those mammalia whose
remains are present in the breccia at the base of the gravel at
Hessle (some of whose remains also, according to Mr. Godwin-
Austen, are associated with the marine mollusca in the Selsea mud-
bed), took place during the period which, from its having been pos-
terior to the elevation of Britain from its great glacial submergence,
we have for more than a quarter of a century been accustomed to
call post-Glacial. ;

1 A restoration of the supposed geographical features of the British Channel at
this time according to my views is given in the fig. No. III. of the Sheet of Maps
and Sections which accompanies my paper on the Weald in the 27th volume of the
Quart. Journ. of the Geol. Soc.; see also Gzou. Mae. Vol. III. p. 348.

S. V. Wood, jun. American and British Surface-Geology. 23

Geologists have so long been cognizant that a minor glaciation oc-
curred in Switzerland subsequently to the first and great extension
of the Alpine glaciers, that it is unnecessary for me to do more than
cite it in corroboration of the conclusions to which an analysis of the
evidences offered by Britain and Eastern North America seem to me
to point; while according to the abstract of a paper by Mr. G. M.
Dawson on the Superficial Geology of British Columbia (read before
the Geol. Soc. of London on 20th June, 1877), this gentleman dis-
covers on the north-west side of North America similar evidence
of two glaciations divided from each other by a warm period.

The semifossiliferous condition of the Selsea shells coupled with
their recent and more southern facies is not the only indication of a
warmer marine climate having occurred in Northern Europe at a
very late date geologically speaking, for Torell and others found in
Spitzbergen some beds of what are called by them “ post-Tertiary ”
shells, containing Mytilus edulis, which is not known as now living
there ; and Nordenskidld (Journ. of the Geograph. Soc. 1869, p. 1386)
speaks of these beds as containing plant-fragments and subfossil
marine shells, of which some now first occur in living condition in
the northern part of Norway. This recent, more southern, and sub-
fossil condition of the Spitzbergen shells, is just that of the Selsea
ones, and is altogether in contrast with that of the shells of all Hast
Anglian Glacial (in the sense I use that word) deposits, which are
thoroughly fossilized, besides containing among them forms charac-
teristic of their superior age. Indeed, some of my Bridlington shells
imbedded in indurated sand are in the condition of Oolitic fossils ;
for which but for their species they might be mistaken.

Mr. Geikie in the second edition of his work having made copious
reference to the Hessle beds as described by myself and Mr. Rome,
and (though making some confusion between our views and those of
the late Prof. Phillips!) having also adopted the view of their
position in the general sequence of deposits for which we contended, ~
as well as their correlation with the upper clay and (so-called)
middle sand of the North-west of England, which I have for several
years past suggested,’ the only difference that ‘seems to remain
between us in reference to them concerns the mode in which the
clay originated. This clay Mr. Geikie insists is not only terrestrial
in its origin, but is a morainic accumulation over a land-surface,
beneath an ice-sheet, and left where engendered. I on the contrary ©
have contended, and still maintain, that it is a submarine accumula-

1 Professor Phillips not only never recognized what we contended was the true
position of the Hessle beds relatively to other Glacial or post-Glacial deposits, but
he had not up to the time of our paper even recognized that the Hessle beds were
distinct from the mass of the Glacial clay of Holderness, which latter he then regarded,
not only as identical with the ordinary Glacial clay of East Anglia (Upper Glacial or
ae chalky clay), but as identical also with the (Lower Glacial) beds of Cromer

it.

2 Report of Brit. Assoc. for 1870, Gzon. Mac. April, 1872, p. 176, and Sept.
1876, p. 396 (footnote). In a paper also ‘On the Climate of the Post-Glacial
Period” in the same Mac. for April, 1872, p. 153, I drew attention to what appeared
to mee be evidences of the recurrence of a glaciation of minor extent during that
period,

24 §.V. Wood, jun.—American and British Surface- Geology.

tion, which, though it may be partly, is not wholly of morainic origin ;
neither has it been left (in Holderness, at least, where it rests on
fossiliferous stratified sands) by submarine ice-recession, as has been
the case with so much of the Upper Glacial clay. Further north,
and also at its higher elevations. such may have been its morainic
origin, but in Holderness and East Lincolnshire it presents very
little appearance of morainic derivation at all; for the Chalk which
it contains is not only small in quantity in comparison with the
basement (Glacial) clay of that district, but is subangular, whereas
that of the Glacial clay is all of it rolled. Moreover, as it occurs
directly over the basement clay (of Upper Glacial age), which is
densely crowded with Chalk debris, it ought, occupying the same
place in reference to any ice-sheet, and seeing that nearly all the
Chalk Wold would, by being left bare of Glacial clay, have supplied it
with Chalk debris, to be equally crowded also if it had originated in
the same way. Mr. Geikie illustrates his argument of its origin by
figures of sections which show not only the junction of the clay
with the sand to be irregular, but to be accompanied by the protrusion
of a portion (or leg as he says the workmen called it) of the clay
into the sand (Great Ice Age, p. 376). This, however, is a feature
which may be met with occasionally in the case of the chalky (upper
Glacial) clay resting on the middle Glacial sand in Hast Anglia,
where also a much more marked irregularity is not unfrequently
to be met with, which at one time misled me into the idea that a
small fault had occurred in those places. They, however, all now
seem to me explicable by the material in these cases having fallen
not only en masse, but with the mass possessing a ragged or irregular
form. I have already explained the reasons which forbid my be-
lieving that in any case, either where these quasi-faults occur, or
where the clay rests on the sands with an even line, the morainic
material could have been pushed over the sands by glacier-ice ; and
my convietion why such cases can only be reconciled with the
dropping of the material on the stratified and undisturbed sands
containing marine organisms upon which it reposes, while these
sands formed the sea-bottom unincumbered in that part with glacier-
ice; and there, with that of the leg described by Mr. Geikie, I leave
the question.

Mr. Geikie, however, is silent on the fact that I have from nearly
the outset of my investigations, and long before any one else took
the view, urged that the Hessle beds were synchronous, or nearly so,
with the Cyrena brick-earths of the Thames Valley;! so that he
argues this synchronism as though the view were new to him; and
Mr. Skertchly seems, in lecturing lately at Norwich, to have been in
similar ignorance of my long contention on this head. Mr. Geikie
also takes exception to my nomenclature of these beds as “ post-
Glacial,” insisting that they should be called “ Glacial” ; but had I
not called them what I did, my contention of their synchronism would

1 See Quart. Journ. Geol. Soe. vol. xxiv. p. 174 (Nov. 1867); vol. xxvii. p. 22

(Nov. 1870); Gzou. Mag, Jan. 1870, Vol. VII. p. 19; and April, 1872, Vol. IX.
p- 176.

S. V. Wood, jun.— American and British Surface-Geology. 25

have produced great confusion. The memoir of Mr. Prestwich in
the Philosophical Transactions of 1864 was, at the time of the paper
by myself and Mr. Rome, the principal work of reference relating to
the beds yielding Cyrena fluminalis, which either then had, or since
have yielded Paleolithic implements ; and Mr. Prestwich in point-
ing out that some of them afforded clear evidence of having been
deposited while ice-action, so far as rivers were concerned, was in
progress, designated them as post-Glacial only because he regarded
them as posterior to the Boulder-clay of the Eastern and Hast
Midland counties (the chalky clay), a formation which was then
regarded as the one great and only clay accumulation of the Glacial
period on the Eastern side of England, but which I have long been
endeavouring to show was preceded by the Cromer Cliff beds, and
succeeded by the Hessle.

In this way the beds yielding Cyrena fluminalis, in common with
many other gravels yielding Paleolithic implements, but which did
not contain that shell, though yielding other freshwater mollusca
(which in some instances may have arisen from their being more
remote from the sea or tidal water to which the Cyrena seems to
have had some proclivity), came to be regarded almost universally
by English geologists as post-Glacial ; and it was expressly with
the object of preventing confusion that I called the Hessle beds,
which, in Holderness at least, did not appear to me to possess the
same characters as are presented by the beds which I call Lower
and Upper Glacial, but yet were, in my opinion, synchronous with
the Oyrena brick-earths, “ post-Glacial” also. In so doing, however,
both in our coast section and in the descriptive part of our paper,
Mr. Rome and I specially pointed out their anteriority to other
river and later valley-gravels of Holderness, some of which where
intersected by the coast, as at Hornsea, are of considerable thickness,
and interstratified with clay laminz containing freshwater shells ; and
the position of these may be seen in Section I. of the Plate which
accompanies this paper. Thus, while in order at the same time to
preserve their synchronism with the Cyrena brick-earths, as to show
their anteriority to many of the gravels yielding Paleolithic imple-
ments that had been called indiscriminately “ post-Glacial,”’ we
distinguished these Hessle beds, as “older post-Glacial.” It is not
a matter of much moment what names we select or accept for
geological formations, so long as, by their use, confusion and mis-
apprehension are avoided ; but if we relegate these Hessle beds to
the Glacial group, we abandon the age of deposits as the basis of
their nomenclature, for the conditions under which they have been
accumulated ; and thus, to be consistent, we should term Glacial not
only the deposits now going on in the Arctic regions, but even the
beds forming in the Sound at Copenhagen, on the shores of which
all our English cereals grow, for according to the authority quoted
by Sir C. Lyell (Principles of Geology, 1872 edit., p. 383), a ship
sunk at Copenhagen in 1807 is now almost buried in erratic blocks
brought by the Baltic ice since that year.

I have confined my suggestions of probable synchronism between

26 8. V. Wood, jun.—American and British Surface- Geology.

the Glacial features of North America and those of Britain mainly
to English beds, because I have for several years urged that none of
the Scotch beds can be older than the newer portion of the Upper
Glacial, viz. the purple clay of Yorkshire where the chalk debris
disappears, and the other chalkless clay to the north of it, which
consist probably of morainic material left by the ice after it had
receded from the lower ground of Yorkshire, overlain more or less
by clay and other beds of Hessle age. Looking at the mountainous
condition of Scotland, and that this part of Britain must have been
that to which the ice of the major glaciation clung latest in its reces- _
sion, it seems to me that all the earliest part of the morainic material
which was coeval, not merely with the chalky clay of Hast Anglia,
but even with all that in Holderness which contains any chalk
debris, must lie out beyond the present coast-line of Scotland, and
under the North Sea and Atlantic, having accumulated when the ice
of that part of the Glacial period to whose recession it was due
terminated beyond the present Scottish shores. When Tellina obliqua
and Nucula Cobboldice have been found in the Scotch Glacial beds,
there may be reason to regard the oldest part of the Scotch clay as
coeval with that portion of the English Upper Glacial which Bridling-
ton Cliff represents in the horizontal succession; but until these do
so occur? I cannot see any reason for assigning an older date to the
Scotch Till than above mentioned. Indeed it seems to me open
to doubt whether much of it belongs to the period of the first or major
glaciation, by reason of the improbability that beds of such character
as glacial accumulations could have resisted the degrading action of
any later ice. Such part only as by submergence during the minor
glaciation was protected from the ice of that glaciation can, it seems
to me, belong to what I term the Glacial period. The well-known
case of Chapelhall in Lanarkshire appears to me to be an instance of
this; for there the submergence of the Hessle period (which I have
described as commencing in the South with the insignificant depth
under which the Fen gravel accumulated, and increasing gradually
northwards) having attained upwards of 500 feet, the sediment
derived from the glaciers of the minor glaciation has been deposited
over mollusca which lived upon the surface of the submerged (and
so protected) moraine left by the recession of the ice of the major
glaciation. The occurrence of Reindeer horns and some few other
mammalian remains in Scotch beds, seems also to receive satisfac-
tory explanation by reference to this minor glaciation.

Mr. Geikie, in the 2nd edition of his work, seems to feel the
difficulty of earlier Glacial deposits having in Scotland escaped the

1 Latitude can have nothing to do with the presence of these shells, because, among
the derivative fossils of either late Crag, or early Glacial age, found by Mr. Jamieson
in gravels capped by Boulder-clay, near Aberdeen, which he sent me for examination,
there was an undoubted fragment of Nwcula Cobboldie, showing that this species had
once lived there; and Tellina obliqgua has been found associated with the other
Upper Crag Ze//ens, in beds in Iceland, whose fossils correspond with the later Crag
beds. If, as I suspect, most of the ice-formed beds of Scotland belong to the minor
glaciation, the ice of which destroyed the preceding beds as far as it extended, the

derivative molluscan remains found by Mr. Jamieson probably constitute part of the
wreck of the deposits of the first or major period of glaciation in that country.

S. V. Wood, jun — American and British Surface-Geology. 27

destroying agency of the ice-sheet to which the Upper Glacial clay
of Hast Anglia was due, and to be more inclined than he was to adopt
the view of the later age generally of the Scotch beds; but he is not
definite upon the subject, and still seems to regard the Scotch Till
as including beds of all stages of the Glacial period. I am glad,
however, to see that he is more disposed (as, for instance, in the case
of the Wexford gravels!) than he was to allow molluscan evidence to
have its weight in determining the age of Glacial deposits.

Mr. Geikie has thought it necessary to put a special erratum at
the commencement of his second edition, that he finds Mr. Jeffreys
stating in Phillips’ Geology of Yorkshire, that instead of there being
five of the Bridlington shells not known as living, all of them are
identical with species found living in Arctic and Northern Seas. It
should be known, therefore, that these identifications are not matters
of recent discovery, such as from dredgings or otherwise, but matters
of opinion upon which Mr. Jeffreys is not in accord with some of
his fellow conchologists. That difference of opinion extends to a
considerable number of the Pliocene mollusca, Mr. Jeffreys’ method
being to call any Pliocene shell which comes near to a species known
living as identical with it, or at most a variety of it; but if after-
wards something more closely resembling the fossil is discovered
recent, then the former identification is abandoned, and the living
species first called identical with or a variety of the fossil is sepa-
rated from it, and the fossil form is allowed to stand as a good
species, because it is found living. By pursuing through the Miocene
and Hocene fauna, successively, this method of calling all Pliocene
shells that approximate to living ones varieties of the latter, and
these again varieties of their Miocene and Hocene predecessors, some
astonishing results may be elaborated in the way of making a large
per-centage of Eocene Mollusca identical with living species, con-
trary to the generally received opinion of geologists.

So slight, however, is the change which has taken place in shells
during long periods, that many Hocene shells do not differ more
from their nearest living analogues than do certain of these Bridling-
ton ones ; and if Mr. Jeffreys can point out any clear natural rule or
law which will define where varietal difference ends, and specific
difference begins, he will throw great light upon the study of living
and fossil organisms, and cause evolutionists seriously to re-consider
their views.

Two out of the five thus said by Mr. Jeffreys to be living are Nucula
Cobboldie and Tellina obliqua. These shells abound together in the
newer beds of the Crag, and in the Hast Anglian Glacial. Both are
found at Bridlington ; and one, the Nucula, in the centre of the 200
vertical feet of morainic clay of Dimlington in Holderness,’ in such

1 The Wexford gravels, if the fauna given from them be reliable, would also seem
to be a remnant of the beds of the earlier glaciation in Ireland; for along with some
other peculiar forms, a fragment of Nucula Cobboldie is mentioned by Forbes as
having been found in them. It is, however, possible that this fragment might have
been one of Lucina (Loripes) divaricata, a living British shell.

2 The place is indicated on the accompanying map, where also the dotted line shows

the position of the Chalk floor down to which, from contiguous borings, the chalky
clay has been found to descend.

28 S.V. Wood, jun — American and British Surface- Geology.

a position as to prove that it lived there. They appear to me to be
conspicuously shells of the earlier part of the major glaciation, and
they are absent from the Scotch’ and all other English Glacial beds,
as well as from all beds of post-Glacial age. The Nucula has been
identified with more than one species living in the Pacific, apparently
from conchologists not being acquainted with the full-grown Crag
and Glacial shell; but from this full-grown shell the Pacifie speci-
mens differ widely.”

The Teilina is called by Mr. Jeffreys a variety of the peculiarly
Glacial species lata (calcarea or proxima), which lives in Arctic
seas, and characterizes the beds of the North-west of England and
Scotland, and is found in Hast Anglian beds of Hessle age; but,
unless he has met with it since I inquired of him a few years ago,
he does not pretend that the shell itself (7.e. the variety as he calls
it) exists in a living state. These two forms of Tellina (lata and
obliqua), whether we call them varieties or species, lived together in
all beds from those of the Red Crag to that of Bridlington; but, as
far as yet known, the form lata is the only survivor of the two from
the stage indicated by the Bridlington bed. Considering the great
difficulties which beset the elucidation of Glacial formations, and
how small is the assistance furnished by Paleontological evidence
towards that elucidation, I am surprised that the facts concerning
this Nucula and this Tellina have not met with more attention than
they have hitherto done.

In conclusion, I beg, although I have dissented from some of
his views, to tender Mr. Geikie my congratulations on the produc-
tion of his able book—a work that will doubtless much extend the
interest felt in the evidences of an age which, although the latest
of geological periods, is, from its association with the history of
Man in our latitudes, the most important of any.

P.S.—The whole of this paper having been in type before the
November number of the Quarterly Journal of the Geological Society
(No. 152) was issued, I was in ignorance of the tenor of the paper
in that Journal by Mr. Mackintosh, on the sections around the
estuary of the Dee; but having become acquainted several years
ago with sections in that neighbourhood, as well as with the limits
and distribution of the Upper Boulder-clay and Middle sand, I had
then satisfied myself of, and suggested to geologists the identity of

1 Except the derivative fragment found by Mr. Jamieson in the gravel near
Aberdeen, referred to in a previous note on p. 26.

2 Five living species of Mucula with divaricated markings like Codboldie are
known. They are confined to the Pacific Ocean, and have been described under the
following names, viz. V. mirabilis (from Japan), NV. divaricata (China Sea), NV. in-
signis (Japan), N. castrensis (Sitka), and NV. Lyalli (Vancouver). The first named
is about one-third of the size of the full-grown Coddoldie, while none of the others
exceed a ninth; and their hinge-teeth are from 4 to 9 fewer. The divaricated marks
in all five extend to the margin of the shell, while Codsoldie has round this margin
a broad belt which is free from them. It is possible, though hardly probable, that
all the specimens yet obtained of these five species are those of young individuals
which might have grown into a mature shell like Codboldie ; but until a specimen of
the kind can be produced, it is as reasonable to identify any of these Pacific species
with Cobboldie, as with the divaricated Nucu/e from the Gault.

Prof. Milne—Across Europe and Asia. 29

those formations with the Hessle beds. The sections now given by
Mr. Mackintosh may be advantageously compared with those of
Holderness in the plate accompanying these pages, which was drawn
by me in 1872. The limit in elevation of the upper clay in its
marine form in Lancashire Mr. Mackintosh puts at 150 feet,! and he
refers the accumulation of it to the same agency as that to which I
refer the Hessle clay. The molluscan fauna of the upper clay, as
well as of the middle sand and lower clay of the same region, has
lately been described by Mr. Shone in a paper before the Geological
Society ; but as it is not yet published, I do not know what additions
he may have made to those species from these beds which have at
different times passed through my hands (and of which I have kept
notes), or to the list given by Mr. T. M. Reade in vol. xxx. of the
Quarterly Journal of the Geological Society, p. 30.2 A comparison
of them should be made with the list of species from the Hessle
beds (Kelsea Hill, March, and Hunstanton) given in the tabular
list to my father’s Crag Mollusca Supplement in the volume of the
Paleeontographical Society for 1878, extended by a note at page 121
of the Quarterly Journal of the Geological Society, vol. xxxiii.; not
forgetting, in the case of the shells of the middle sand and upper
clay of the North-west, the probability of their having to a more or
less extent been derived from the destruction of beds of Moel
Tryfaen age. It will also be found, I think, that the middle sand of
the Lancashire low ground has been confounded at high levels with
sands of Moel Tryfaen age, which belong to the latest part of the
Upper Glacial, as well as, possibly, with gravels of Kame origin,
which, though they belong to the Hessle period, are of somewhat
later date; having been formed by the subaerial melting of the
glaciers of the Hessle period during the wane of the minor glacia-
tion, and therefore either synchronous with, or posterior to, the
upper clay.

IIJ].—Across Hurore ann Asta.—TRravetiing NotEs.

By Professor Joun Mine, F.G.S.;
Imperial College of Engineering, Tokei, Japan.

(Continued from Dec. II. Vol. IV. p. 568.)
VIII.—Lake Baikal to Kiachta and across Mongolia.

ContEents.—Lake Baikal to Kiachta—Description of route—Volecanic district near
Poyorotnaya—Voleanic district of the Tunka—Across Mongolia—Kiachta to
Urga—Description of Mountains—Drift—Urga to Kalgan — Description of
route—Granite Boulders—Volcanic Rocks.

BOUT 5:30 p.m. on Thursday, 15th November, I said good-bye
to Lake Baikal, and branched off upon a road to the right
leading to Cabansk. Along this road, which was a very bad one,
there was an apparently untouched forest of birch and pine, with
here and there a clump of aspen. For some distance upon my left

1 Mr. T. M. Reade, Quart. Journ. Geol. Soc., vol. xxx. p. 30, gives shells from

apparently this clay (Brick clay) at 175 feet.
2 This list, in so far as it reters to the occurrence in the Crag of species named in

it, contains several imaccuracies.

30 Prof. Milne—Across Europe and Asia.

extended a wide lake, which joined the Baikal. After much reckless
driving across wide trackless plains, through gaps in ridges, snow
drifts and clumps of trees, with a wild and drunken coachman, at
half-past eight I found myself at the post station of Cabansk.
After a windy and bitterly cold night, I was next morning at the
station of Palavinsaya, the country round which is hilly and pretty.
The next station was situated in a plain between sloping hills and
isolated peaks. These hills being without wood, the country had an
open appearance. As I went on, the snow, which I had been told in
Irkutsk would be continuous as far as Kiachta, grew less and less,
and at the station where I next changed horses, I had to abandon the
sledge I had purchased and hire a carriage. Although the roads
were now tolerably free from snow, the surrounding hills were still
white with it. The next morning I passed the station of Povorot-
naya. ‘The soil now became sandy, and the only trees were pines.
The way in which these were dotted about in clumps gave a park-
like aspect to the district. In passing through a gap on the ridge of
some hills which had been before me since leaving this last station,
I came upon one of the most extensive views I had seen upon my
journey. The country then before me was smooth and undulating
in outline. Here and there small conical hills like old volcanos,
the tops of which were sometimes capped with trees, stood up like
islands above the plains of snow from which they rose. In and out
between these I could see the track I had to take, trending away in
the distance until it almost disappeared as a mere black line. From
the little 1 saw of this country as I went rapidly rolling through it,
it appeared to be a region of old volcanos, which would admirably
bear comparison with Scrope’s drawings of the Auvergne. Hvery-
where upon the road were black fragments of volcanic rocks, which
were often vesicular and sometimes scoriaceous. To the right and
to the left were small cones throwing shadows on the snow as even
and distinct in their conical outline as the volcanos themselves. After
crossing a small ridge beyond the station of Kalenishnaya, up a
valley upon my left there was a large cone with a broken crater,
down the sides. of which the outline of an ancient stream of lava
could be distinctly traced. At one or two places along the valley
in which I travelled there were some large fissures extending down
from the mountains. These were generally ten to twelve feet in
depth, and from twenty to forty feet in width. In some places they
intersected the road and had to be crossed by a bridge. These
openings showed sections of a greyish sandy soil, which may be
regarded as an alluvial covering to the volcanic rocks beneath.

The voleanic rocks of the Tunka district, to which I have before
several times referred, hold a somewhat similar position to the alluvial
beds which cap them.

The serrated outlines of the mountains which bound this last-
mentioned district, J saw on my way down the Baikal, and I also
mentioned them as being visible from Irkutsk. A general idea of
the situation of these rocks may be gathered from the annexed
section, which I have drawn from a description given to me by M.
Tchersky, who had paid a visit to the Tunka valley.

Prof. Miine—Across Europe and Asia. : ol

This section runs from 8.E. to N.W. across the valley of the River
Irkut, from the Syen Mountains to the Tunkusian Alps. These
latter are made up of limestones and pyroxenic rocks which are
much metamorphosed. All that is known about them at present is,

Syen River Tunkusian
Mountains. Irkut. Alps.

A,A,=Alluvium. L,L,=Lava.
Diagram section of the Irkut Valley (after M. Tchersky).

that they are older than the Jura sandstones, beneath which they are
seen to pass. In the valley between these two ranges of mountains
there are beds of lava and of alluvium. ‘This, like that on the road
to Kiachta, is basaltic in character. I often inquired about felspathic
lavas, but I never heard of them. ‘The colour of this lava is black,
or some shade of black or bluish black, and occasionally grey. It
is generally compact. When it is scoriaceous, it sometimes has a
reddish-grey colour. Many of the specimens which I saw con-
tained much olivine. In some places, as near Tunka, there are
small hills of lava. These were at first thought to be old craters,
but are now only supposed to mark the places where the lava may
have welled up through fissures. The beds of lava are not the
result of one flow, but of several. This may be seen at several
points where there is evidence of one bed of lava having flowed,
become cool and scoriaceous in its surface, before a bed which
may be seen lying upon it ever issued from the crater. In some
places as many as six beds may be seen lying one upon the other,
each compact at its base, but gradually merging into a scoriaceous
character above. At one locality M. Tchersky described to me
instances of the peculiar concentric structure which the lava had
assumed.

From the evidence we have, the outburst of the Tunkusian
volcanos must have extended over a long period of time, apparently
having commenced before the excavation of the Tunka valley, which
they partly filled with their products. The next step was the
wearing away of these lavas into hollows, and into these an
alluvium, probably identical with that which now covers a great
portion of Siberia, was deposited. That this deposition was general
in its nature is evident from the corresponding position of similar
beds in neighbouring depressions. At the base of the alluvium
there are rounded pebbles of basalt derived from the rocks beneath.
In these deposits Mammalian remains such as of the Mammoth and
Rhinoceros have been found. Some of these beds are found as
much as 1157 feet above the village of Tunka, which is itself at

32 Prof. Miine—Across Europe and Asia.

a considerable height above the Baikal, and therefore at still greater
height above the level of the sea.

This would bring these deposits of Siberian alluvium almost, if
not quite, upon a level with any that have been deposited upon the °
Mongolian plateau, about which I shall speak presently, both of
them indicating a great depression of land beneath water that was
in all probability fresh in recent times. Up this same valley there
are some beds of unstratified alluvium, in which there are buried
angular blocks of rock not belonging to the district in which they
are found. Although I made all inquiries I could about these,
their discoverer, M. Tchersky, did not lead me to understand that
they afforded evidence of glacial origin. Nevertheless, further
observations may show them to have been derived, perhaps, from
local glaciers. If this is so, then we have a fragment of the evidence
that is needed to establish the fact that this portion of Siberia was
once invaded by ice. When this is adduced, the origin of the earlier
deposits of the Siberian drift may be explained in a manner different
to that which I have suggested.

On the same afternoon that I passed through the volcanic district
of Kalenishnaya, I met one or two tea caravans. The flat faces and
oblique eyes of the men who drove these told me my European
associations must soon end, and I should be very shortly among the
Mongols. That night I reached Troitskosarsk. This town lies near
the head of a sloping valley, bounded on either side by hills of a
moderate height. About two miles from this, down the valley, is
Kiachta, the Russian frontier town, which immediately abuts on
the palisaded Chinese town of Miamachin. These three towns are
better known and spoken of under the name of Kiachta, which is
the smallest of the three. It is seldom that there is sufficient snow
about Kiachta to enable sledges to be used; however, there was
quite enough upon the surrounding hills to prevent me from ascend-
ing them. In the valley there are beds of an earthy sand, through
which, in places, I saw sections twenty feet in thickness, cut by a
small stream which flows down through them towards the Selinga.
The wearing away of this sandy covering gives the arenaceous charac-
ter to the soil of the neighbourhood, which is so striking to all visitors.

At Kiachta I was delayed several days before I could complete
my arrangements for crossing Mongolia, which was now before me.
My intention had been to travel with a Russian officer whose
acquaintance I had made in Irkutsk. In Kiachta my intentions were
frustrated by the Commissary of the Frontier showing me that as
my friend was to travel as a courier by a special route, it was not
permissible to allow me to proceed by the same road, without
violating arrangements entered into between the Russian and
Chinese Governments respecting couriers and the routes they travel.
Disappointed in this, I next made arrangements to accompany some
Mongols who were conducting a caravan as far as Changiakau or
Kalgan, the frontier town between China and Mongolia. I had five
camels for myself, my baggage, and a Cossack, whom the Commissary
very kindly allowed to conduct me as far as Pekin.

Prof. Milne—Across Europe and Asia. 33

It was the 9th of December before I started. After passing
Miamachin, which I may remark is the cleanest town in China, we
were soon in the open country and upon a sandy tract between low
smooth hills. Towards evening we entered a flattish plain, after
crossing which we were again among some hills. Owing to the
slipperiness of the road, we had great difficulty in getting our
camels up the steeper slopes. It was now bitterly cold, the tempera-
ture varying between —18° and —21° R.; sometimes it was rather
less, and often more. During this portion of our journey we took
advantage of the moonlight nights. Starting at 10 a.m. we generally
travelled continuously until 7 or 8 p.m., when we rested half an
hour for tea, after which we continued until 2 a.m. before finally
resting tor the night.

On the morning of the 11th we passed near the valley of the
River Sharinkol, where there were some fir-trees on the hills, and in
the afternoon we passed along a valley bounded on either side by a
series of low peaks. The only birds we saw were ravens, magpies,
a small finch, and some sparrows. We met with the former of
these along the whole of our route across the desert. They were
very bold, and in spite of our best endeavours they continually
settled on the backs of our camels, to tear open the provision bags.

At many points along this portion of the route the growth of
trees upon the northern slope of the hills, while the southern side
was barren, was very noticeable. As a consequence of this, these:
southern slopes, being destitute of any covering which could prevent
the percolating water and other denuding agencies from carrying
material away, were steep and scarp-like; whilst the northern slopes,
with their protective covering of vegetation, were more gentle
in their inclination.

It might of course be argued that it was the gentle slope which
produced the trees; but I hardly think that this could have been the
case, as ] saw examples of gentle slopes towards the south which
were as equally destitute of any covering as the steeper ones. In
many of the valleys I saw sections of a sandy drift something
like that around Kiachta, which must in certain cases have been
more than forty feet in thickness. In the upper parts of this I
observed many fragments of granitic rocks.

On the night of the 11th, about 12 p.m. we entered a steep pass
called the Makatah, and it was not until 2 p.m. next day, after 27
hours of continuous travelling, that we could consider ourselves
to be fairly through it.

At about midnight on the 13th Dec. we crossed the Olindowa Pass,
and at 7 a.m. the Gutinawa Pass, reaching Urga on the afternoon of
the same day. The approach to the town ‘is down a broad flat
valley, bounded on either side by steep hills. At right angles to th
end of this valley there is a high range of hills, beneath which, at
the confluence, so to speak, of three openings in the range Urga is
situated.

Up to this point, all that I saw were a few granitic rocks, and a
considerable covering of alluvium.

DECADE II.—VOL, Y,—NO. I. 3

o4 Prof. Miine—Across Europe and Asia.

I left this religious Mongolian centre, which is the residence of
a living Budda, on Thursday the 16th of December. The valley by
which I made my exit was to the left, and at right angles to the
one by which I had entered. It was about three-quarters of a mile
broad, and was covered with large boulders and rounded stones.
Some of these were granite, others sandstones, and others, I think,
were limestone. There were also some chloritic crystalline rocks
like greenstone. Not long after leaving Urga, we led our camels
over the frozen waters of the River Tola, which was apparently
made up of two streams, each about twenty yards in breadth. On
some of the hills, where steep scarps prevented an accumulation of
snow, red-coloured stratified rocks dipping towards the south were
visible. Before the end of the next day the trees, which had been
gradually becoming scarcer, entirely disappeared. With this dis-
appearance, the magpies, which had thus far accompanied us, also
disappeared, and all that we had left as companions were large
black ravens. The country was hilly, but smooth in outline, until
the morning of the 19th, when we entered a large plain, which was
brown with grass cropping up through a thin covering of snow.
The hills surrounding this plain, which was typical of the country
for several succeeding days, although not high, were very rugged.
On examination I found them to be made up of black, and in some
few cases reddish rocks of volcanic origin, which were apparently
basaltic. Where the snow had been blown away by the wind,
or worn away by traffic, I often saw large quantities of agate,
jasper, and chalcedony, resulting from the decomposition of the
amygdaloidal portions of this rock. On the 22nd we reached a
village called Teck-sha-buinta, where I narrowly escaped hostilities.
The country beyond this was very similar to that which I had just
been traversing. Most of the hills were low and undulating, but
some few rose to heights of about 400 feet, and had ragged
summits. In addition to the black basaltic rocks, there were now
some pinkish porphyritic felsites. Some of these were phonolitic,
giving out a clear ringing sound when struck. The ground was
everywhere perforated by the burrows of small marmots (Lagomys
Ogotono). 'There were also a few hares (Lepus Tolai), 1 few large
kites, and ravens, and two or three finches to be seen. These, with
a few antelopes (Antilope gutturosa), and an occasional partridge
(Perdix barbata), constituted the desert life.

Through some of our camels suffering with sore feet, I was
delayed for two days at a place called Kooistilroi, where there were
two or three felt tents or yourts, the head-quarters of a Mongolian
Mandarin. I left this place on the 25th December. On the evening
of the same day, near our first camping place, I saw some large
boulders of granite. These were lying on the surface of the ground,
and, I think, must have been produced by disintegration from the
rocks on which they rested. All next day the country through
which we passed was granite, and there were so many boulders
lying about, that during the night it was necessary to have a lantern
in order to steer safely through them. On the 28th these boulders

Prof. Miine—Across Europe and Asia. 30

were so numerous that they formed quite a rockery like feature in
_ the landscape.

On the 4th of January the character of the country changed, and
it now looked as if the whole surface of the ground had been cut
up into earthworks for purposes of fortification. Instead of the
gritty remains of a degraded granite, we now had much red sand.

At 11 a.m. next day we sighted mountains before us. From the
fragments of rock strewn about in the pass leading through them,
they probably consisted of granite and greenish porphyry. The
place at which we crossed was called Haita, and the mountains, I
believe, the Ugundui Mountains. At this point magpies again
appeared. The rest of our road was mostly over rolling plains,
with here and there a ridge. By daybreak on the morning of the
9th of January I was leaving the Mongolian plains, and was
descending a steep and rocky pass towards Kalgan, which was then
almost beneath my feet, there being on all sides of me rocks of
unmistakably volcanic origin.

While on this portion of my journey, which lasted 31 days,
the thermometer registered from 0° to —24° R. The ground was
almost everywhere covered with snow, which we had to scrape away
whenever we wished to pitch our tent. This was generally about
3 P.M., when we rested until 9 p.m., the remainder of the 24 hours
being spent in continuous travelling, time not being allowed even
for food. I had only one opportunity to take off any of my clothes,
and that was at Urga, where I also had a wash. This latter action
I repeated three times when the thermometer rose to —10° R.
My time was chiefly spent in trying to thaw food for myself over
a small fire of camel’s dung, or else in endeavouring to keep warm.
These circumstances, together with the fact that I was so bundled
in skins, that it was with difficulty I could walk, will, in part,
account for the meagreness of my observations along this section of
my journey, and the only reason that I now venture to offer them is,
that so little is known of this portion of the world.

Conclusion.—This portion of Mongolia lying between Kiachta and
Kalgan, according to the measurements of MM. Fuss and V. Bunge,
and later Fritsche, would appear as a saucer-shaped plateau, the
outer edges of which are about 5000 feet above sea-level, while the
inner central part is only from 2000 to 2400 feet. The ascent to
this table-land is gentle and by a series of undulations upon the
northern side, while on the southern side it is precipitous and by a
single pass. ‘The inner parts of this saucer, which is more elliptical
than circular in form, slope gently towards a level central area. The
whole of this shallow basin is traversed at intervals by low moun-
tains and rounded hills. From what I saw it would appear as if
volcanic rocks formed the predominating geological feature of the
country. These in the northern parts were more or less basaltic
and very often amygdaloidal. The amygdules of these rocks were
filled with some siliceous mineral like quartz, and this, I may add,
generally had a coating of a chloritic mineral interposed between
it and the sides of the cavity in which it rested. In the more

36 Prof. Miine—Across Europe and Asia.

southern parts of the volcanic districts the rocks appeared to
be more felsitic in their character. Some of these were markedly -
porphyritic, while at Koorstelroi they were phonolitic. The rocks
which form the lower edge of the plateau near Kalgan are described
by Pumpelly as being porphyritic felsites. Those which I saw in
the upper portions of the pass at this point differed from those lower
down: while the upper ones were amygdaloidal and somewhat
basaltic in appearance, the lower ones were felsitic. Where these
volcanic rocks occurred, they generally stood up above the surround-
ing country as hard rough ridges. When they were elevated and
brought to view by refractive agencies producing the Fata Morgana,
which was a common phenomenon while travelling in the desert,
they appeared as rugged islands floating on a level silvery sea.
The other rocks which I saw were chiefly granitic. The first of
these occurred as boulders which I half suspected had been
transported by the action of ice. This I afterwards found not to be
the case, as I shortly afterwards (Dec. 28th) came upon a district
where, by the ordinary processes of degradation, these boulders were
being weathered out from their parent rock. In this district, through
the disintegration of the granite, the road was very gritty and the
ground hard. Apparently as a consequence of this, there was an
absence of the small burrowing pika, which before had been visible
at every point along the road. The buzzard, which feeds upon the
pika, was naturally absent also. Not only would the geological
nature of the district in this way affect the animals, but it would
also have an important influence upon the plants.

In one place, on the 31st December, I noticed a syenitic rock.
Besides these volcanic and granitic rocks, there was the covering of
sandy drift. In the Kalgan Pass this had the appearance of a reddish
and sometimes whitish marl. As to whether the marls and sands
of the Gobi plateau have any connexion with similar deposits in
Siberia, I should be afraid to say before further evidence can be
adduced, all that I can do being to refer to what I said about the
high levels of the terrace deposits in the valley of the Tunka.

Mr. Pumpelly, who traversed this same region in 1864, at a similar
season of the year as that at which I crossed it, was more fortunate
in his observations, this being partly due to his having taken a some-
what different route.

Starting from Kalgan at Lake Bilika Noor, he found horizontally
stratified—1. Yellowish grey limestone; 2. Thin beds of clay or
earth with manganese concretions ; 3. Bed of crystalline gypsum ;
4, Gypsum with red clay. The last mentioned being the oldest or
lowest in the series. This was before reaching the Mingan Hills,
where quartzite, compact sandstone, and a talco-argillaceous schist,
dipping at a high angle towards the N.E., were found. Beyond this,
beds of limestone were met dipping S.8.W. Still further on the
road, a white calcareous sandstone, with thin beds of an interstratified
arenaceous limestone, was observed, Sandstone was next found, and
then granite, until the valley of the Ulanoor was reached, where
clayslate was met with, and afterwards more granite.

W. S. M. D’ Urban—Stone Implements in S. Devon. 37

Beyond this, at the hills of Senji, micaceous, argillaceous, and
talcose schists, traversed with dykes of greenstone, were seen. Beyond
these hills, after eleven days’ journey since leaving Kalgan, basalt
was met with, which rose in cones from 100 to 150 feet in height.
After this, calcareous sandstone, conglomerate and limestone were
met with, which were followed by more granite, mica-schist, and
dolomite.

On the 15th day of travel, trachytic porphyry was met with. On
the 16th day, granitic and syenitic rocks. On the 21st day, just
before reaching Urga, hills of a black metamorphosed slate were seen.
These, together with the Steppe deposits of alluvial material, appear
to have been the chief geological points which were observed.

Placing my fragmentary gleanings along with the notes collected
by Mr. Pumpelly, it would appear that there is considerable geolo-
gical variety to be found upon the Mongolian plateau, which is
usually pictured as a sandy waste, known under the name of the
Desert of Gobi or Shamo.

The younger formations of this area apparently give evidence of
a large sheet of water having at one time covered this portion of the
globe, which in itself probably implies enormous subsidence. Such
vast changes in the relation of land and water in this portion of the
globe, if they can be really shown to have occurred, would at once
give some clue to the climate of past time, the distribution of faunas,
and other like phenomena, which are not only interesting as facts in
the history of our globe, but-which also have a practical bearing
upon our present welfare.

Then there are the volcanos. These, I believe, from what I
learnt from M. Paderin, Acting Russian Consul at Urga, who had
recently made a visit to Ulisaitai, and from what I learnt from other
sources, must have covered an area as large and perhaps larger than
any other volcanic district with which we are acquainted. In the
mountains of Manchuria the flickering embers of these fiery out-
bursts appear to have continued down to historic times, and no
doubt, as Mr. Pumpelly remarks, the violent earthquakes which
shake the districts of North Chihli, and which I have described as of
continual occurrence round Lake Baikal, are remnants of this action.

Altogether Mongolia is an interesting region, and one which
would repay the geologist who could visit it at a favourable season.

_ Norre.—See Geological Researches in China, Mongolia, and Japan, by Raphael
Pumpelly. Smithsonian Contributions to Knowledge. No. 202.
(To be continued in our next Number.)

TV.—PatouitHic IMPLEMENTS FROM THE VALLEY OF THE AXE.
By W. 8. M. D’Ursay, F.L.S.,

Curator of the Devon and Exeter Albert Memorial Museum, Exeter.
T Broom, in the parish of Hawkchurch, near Axminster, close to
the River Axe, in the angle formed by the junction of a tribu-
tary brook with it, is a low hill, the summit of which is about 50
feet above the level of the rails of the London and South-Western
Railway, which runs at its base. This hill consists of a mass of

38 Reviews—Barrande’s Cephalopoda.

chert gravel intermingled with ferruginous clay of a yellow colour,
and interstratified with seams of sandy clay, without shells or other
animal-remains, as far as is at present known. ‘There are a few
much-rolled pebbles of quartz; of a hard dark-grey siliceous rock ;
and of chalk flints, mingled with the chert fragments, many of
which are angular or subangular. It has been cut into for ballast
for the railway, and about half has been removed in the last fifteen
years, exposing asection of from 40 to 50 feet in depth. The bottom
of the pit is on a level with the rails, which are a few feet above the
river, and about 150 feet above the level of the sea, about six miles
distant. The chert gravel was probably derived from the Greensand
which caps the hills inclosing the valley.

In this gravel during the present year have been found numerous
implements of the usual Paleolithic forms, made of very dark brown
chert. Some of them have been much rolled, but the majority are
quite sharp and uninjured. Many have been picked up on the rail-
way after the gravel has been used for ballasting the line. It is
unfortunate that none have been found in siti by any one except the
workmen, but from the nature of the gravel it is very difficult to
distinguish them from the surrounding mass, until they have been
washed clean by the rain. Some have been deposited in the Black-
more Museum at Salisbury, and a large number have been secured
for the Albert Memorial Museum at Exeter.

Norr.—We have been favoured by Mr. W. 8. M. D’Urban with
a set of three photographs, 8vo. size, containing admirable repro-
ductions of the forms of 386 of these Paleolithic chert implements
from the River-drift Gravel of the Valley of the Axe—now pre-
served in the Exeter Museum. They convey an excellent idea of
the form of these unpolished implements, which remind one of the
elliptical form of River-drift implements from Icklingham, and others
of the acutely-pointed and ovate-pointed flint-implements from River-
drift, Hoxne, Norfolk, figured in the Got. Mac. 1873, Vol. X. pp.
4-10, Plates I. and II., copied from “Ancient Stone Implements,
ete., of Great Britain;” by John Evans, D.C.L., F.R.S., V.P.G.S.,
1872, 8vo. (see Fig. 421, p. 490, Fig. 449, p. 519, and Fig. 450,
p. 020). *Mr. D’Urban informs us that ‘copies of these photographs
may be obtained at 1s. 6d. each, or 4s. 6d. the set, which is cost
price.”—Eprr. Grou. Maa.

RAV LEwWwS.-

CipHaLopopEs. Etuprs GinfiraLes; ExTRarts DU SySTEME SILURIEN
pu Centre DE LA Bonkmr. Par Joacuim Barranpg. 8vo. pp.
2538, 4 plates and several tables. (Prague, 1877.)

N this memoir M. Barrande gives us a most interesting, and in-
structive, summary of his valuable researches on the embryology,
organization, distribution and range of the Palzozoic Cephalopods,
with additional notes on the Secondary, Tertiary, and existing
species. ‘The greater part of his observations are, however, founded
on an examination of the Bohemian forms, 1127 in number, or

Reviews—Barrande’s Cephalopoda. 39

nearly one-half of the known species from the ancient rocks of
the two continents. The specimens are said to occur very abundantly,
and in a good state of preservation, often affording evidence of the
internal structure. After a critical analysis of the distribution of the
order in time, and a rigid investigation of the origin and growth of
the shell in the Nautilide, M. Barrande feels a positive conviction
that no facts favourable to the theory of Evolution, or descent by
modification, can possibly be derived from a systematic study of the
Cephalopoda.

In a review of the Embryological literature of the subject, it is
mentioned that Dr. Robert Hooke was the first to call attention (in
a paper read before the Royal Society of London in 1696), to the
initial development of the shell in Nawtilus, and the value of the
publications of Prof. Phillips, MM. de Koninck, Franz Hauer,
Alph. Hyatt, F. and G. Sandberger, etc., etc., in the present century,
is duly acknowledged. It appears from their researches, and those
of M. Barrande, that there exists a most important radical difference
between the early stages of the development of the families Ammon-
itide and Goniatide, as compared with that of the Nautilide, an
ovisac being always present in the former, and absent in the latter.
This fact alone is considered by M. Barrande as sufficient evidence
of the non-derivation of the Ammonites, and Goniatites from the primi-
tive Nautilide, for, it is urged, if a correspondence in the embryonic
characters of diverse genera be regarded as proof of their descent by
modification from some common ancestor, it must necessarily follow
that so marked a contrast is a sure indication of an independent
origin. Again, it is contended that the embryonic type of the
primitive Vautilide persists unchanged up to the present time, while
that of the families Goniatide, and Ammonitide, appears suddenly, and
retains its distinctive characters until the final extinction of all the
genera of which they are composed. Moreover, an examination both
of the external and internal structure of the Cephalopods, whether
as considered with regard to the position and diameter of the syphon,
or the size, curvature, ornamentation, and composition of the shell,
absolutely fails to furnish any evidence of progressive development,
but shows, on the contrary, that any variation in these characters
had no effect whatever, either upon the number of a species, or the
vertical range of a genus. For instance, M. Barrande observes that
although the Nauwtilide possessed of a compound opening might be
looked upon as more highly organized than those with a simple one,
yet both these forms were simultaneously represented in the lowest
beds of the second Silurian zone, the simpler forms also were speci-
fically far more numerous, and endowed with a much greater power
of vitality. Thus, as the accompanying Table shows, five out of the
six compound types were restricted to the Silurian rocks, one only
ranged up to the Carboniferous, while, of the 12 simpler forms, but
six died out at the close of the Silurian, the straight-shelled Ortho-
ceras living on to the Trias, and the whorled Nautilus persisting even
to the recent period. The evidence of the few admitted intermediary
forms is also regarded as invalid, on account of the anachronism in-

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42 Reports and Proceedings—

volved in their first appearance after the genera which they might,
otherwise, be supposed to connect.

The author is also of opinion, that the simultaneous occurrence
of twelve primitive, cosmopolitan types at the base of the second
Silurian zone (=—L.8.) is absolute proof of their independent origin.
It must, however, be noted that the assumed absence of all Cepha-
lopods and Acephala in the primiordial zone rests solely on
negative evidence, and testimony of that nature is subject to con-
tinual modification, of which the long controverted existence of
fishes in the Upper Silurian rocks and of Mammalia in the Pur-
becks may serve as examples. It is probable, also, that Hvolutionists
will be inclined to regard the wide distribution of the so-termed
primitive types as indicating their antiquity, and they will not,
therefore, share M. Barrande’s ideas as to the utter impossibility of
the discovery of a centre of development in some of the unexplored
Cambrian areas. It may be added that in the Lower Tremadoc
rocks of St. Davids, in South Wales (now classed on paleeonto-
logical grounds as Upper Cambrian), Mr. Henry Hicks has already
recorded the presence of one species of Orthoceras and twelve of
Lamellibranchiata.

In concluding his investigations M. Barrande alludes in eulogistic
terms to the admirable memoir by Mr. Thomas Davidson! on
‘What is a Brachiopod?” He refers, likewise, to the publications
of M. Grand’Hury on the Carboniferous flora of Central France,
and to the views expressed by Mr. Carruthers in his address to the
Geologists’ Association,’ as being in complete accordance with the »
results of his own researches, and thus considers it manifest that no
support to the theory of Evolution can be derived either from the
Vegetable Kingdom, or from the Brachiopoda, Crustacea, and Cepha-
lopoda in the animal domain.

The foregoing Table (pp. 40-41), compiled from five of the author’s,
indicates the chief points of his classification, the geological, and
geographical horizons of the primitive types, the vertical distribution
of the families Nautilide, Ascoceratidag, and Goniatide, and the number
of species of each genus in which the embryological characters have
been satisfactorily determined.? A.C.

dea SO1sysS) YNaNpiD) 123s4OCimiz DEL GS).

—

GEOLOGICAL Sociuty or Lonpon.—I.—Noyv. 21, 1877.—John Evans,
Esq., F.R.S., D.C.L., Vice-President, in the Chair.—The following
communications were read :—

1. “On the Glacial Deposits of West Cheshire, together with Lists
of the Fauna found in the Drift of Cheshire and adjoining Counties.”
By W. Shone, Esq., F.G.S.

The conclusions arrived at by the author in this paper were as

Grou. Mac., April, May, June, 1877. 2 Grou. Mae., Dec. 1876.
* For a previous review of M. Barrande’s labours on Cephalopoda, see Gxot.
Mac. 1870, Vol. VII. p. 486.

Geological Society of London. 43

follows :—Like Prof. Hull, he distinguished a triple division of the
deposits under consideration. 1. The Lower Boulder-clay, or, as he
preferred to call it, Lower Glacial Drift, resting immediately upon
the eroded surface of the Keuper, consists for the most part of com-
pact clay, containing numerous and large striated erratics, together
with a fauna of Scandinavian type, the Gasteropoda being generally
filled with fine silt containing Microzoa. The author believed that
the shells found in this deposit were principally distributed by
ground-ice, which took them up and floated them off the shore. 2.
The Middle Sands and Gravels, or Interglacial Drift of the author,
consist chiefly of sands and gravels containing few (if any) glaciated
stones. The fauna of this division is Celtic, with a few Scandina-
vian species derived from the Lower Boulder-clay ; the shells were
distributed principally by currents; and the Gasteropoda seldom, if
ever, filled with sand containing Microzoa. 38. The Upper Boulder-
clay or Upper Glacial Drift, is composed for the most part of clay
not so compact as the Lower Boulder-clay, and containing fewer and
smaller glaciated stones, which are more abundant near the base.
The fauna is Scandinavian at the base of the beds. The shells were
distributed principally by ground-ice, and those of southern type
derived from the Middle Sands and Gravels. The Gasteropoda are
chiefly filled with silt contamming Microzoa. The paper was accom-
panied by lists and tables of fossils, a large collection of which was
exhibited in illustration of the paper.

2. “The Moffat Series.” By C. Lapworth, Esq., F.G.S.

The fossils found in the highly convoluted Lower Silurian rocks
of the southern uplands of Scotland are usually restricted to certain
narrow bands of black carbonaceous and Graptolitic shales, which,
from their especial abundance in the neighbourhood of the town of
Moffat, Dumfriesshire, are known to geologists as the Moffat Shales
or Moffat Series.

The most perfect section of the black shales visible within the
Moffat area is exhibited in the cliffs of the gorge of Dobb’s Linn, at
the head of Moffatdale. It was shown by the author that they are
here disposed in a broken and partially inverted anticlinal, which
throws off on both sides the basal beds of the surrounding non-
fossiliferous greywackes. They are distinctly arranged in three suc-
cessive groups or divisions. Hach of these divisions is distinguished
by special lithological characteristics, and possesses a distinct fauna.
To the lower and middle divisions a few fossils are common, but
between the middle and upper divisions the paleontological break is
complete. These divisions, again, are naturally subdivided into
several zones, each characterized by special species, or groups of
species.

A larger exposure of the same deposits occurs at Craigmichan, a
few miles to the south-west, where the beds of the lower division
are shown to a much greater depth than at Dobb’s Linn. In these
two localities the general succession of the Graptolitic shales is as
follows :—

44 Reports and Proceedings—

Feet.

(c) Birkhill Beene ae and purple flagstones, with

Shales, or | (2) Upper Birkhill | jines of black and white shale .... 70 to 80

Upper - 17:7 ( Black pyritous shales, with seams

Moffat. (2) Morne atau { of brightly coloured clays pei ~ 60 to 70
(6) Hartfell Pale « een non-fossilif

Stat or | (0) Upper Hansen {Peleg ox eeen noseaifrom

Mo a (a) Lower Hartfell Black hard slaty shales and flags ..... 40 to 50
(a) Glenkiin Yellow and grey shales and flags,

Shales, or non-fossiliferous, with a few

Lower bands of soft black Graptolitic

Moffat. Shall este ie ltsnncntnnr ecto canes 150

With the aid afforded by these sections, the thorough investiga-
tion of the ten subparallel black shale-bands of the Moffat area is
rendered a matter of ease and certainty. Of these, the four bands
lying to the south-west of Saint Mary’s Loch are the most continuous.
They were described in detail by the author, and it was shown that
in each the only strata apparent are indisputably those of the type-
sections of Dobb’s Linn and Craigmichan, with which they agree
zone for zone in sequence and in all their characters, mineralogical
and zoological. Here, also, the beds are arranged in greatly elongated
anticlinal forms, the axes of which are, as a rule, inverted. In any
single transverse section, the succession of the beds on the opposite
sides of the median line of the band is identical, and the highest
zone of the black shales everywhere passes up conformably into the
basal bed of the surrounding greywackes. The varying width of the
band is dependent simply upon the varying elevation of the crown
of the anticlinal. Where the band is of least diameter, only the
highest beds of the Birkhill shales rise from below the greywackes.
As the band expands, the underlying zones emerge one by one in
its centre, till finally, in the widest exposures, we recognize the
deepest strata of the Glenkiln shales.

It was shown by plans, sections, and descriptions of every expo-
sure of consequence within the Moffat district that precisely similar
results are arrived at with respect to the remaining black shale-
bands. To the south of Moffatdale, the Moffat beds agree essentially
with those of Dobb’s Linn; but to the north the whole formation
diminishes in collective thickness, and the highest division gradually
loses its fossiliferous black shales.

These facts place it beyond question that all the carbonaceous and
Graptolitiferous shales of the Moffat area are portions of one and the
same originally continuous deposit—the Moffat Series, which is now
the oldest visible rock-group in the district, being everywhere in-
ferior to the prevailing greywackes, through which it invariably
rises from below in greatly elongated anticlinal forms.

In the rigid restriction of distinct groups of fossils to a few feet
of the succession, the rocks of the Moffat series resemble the thin-
bedded Silurians of Scandinavia and North-eastern America. From
analogy it may be suspected that they similarly represent an enor-
mous period of time. The correctness of this inference is demon-
strated by the evidence afforded by the known geological range of

Geological Society of London. 45

their organic remains. The Graptolithina of the Lower or Glenkiln
division are those of the highest Llandeilo Flags of Wales, the
corresponding Middle Dicranograptus-schists of Sweden, and the
Norman’s Kiln shales that underlie the Trenton (Bala) Limestone of
New York. The Hartfell species occur in the Bala beds of Conway,
etc., the higher Dicranograptus-schists of Sweden, and the Utica
and Lorraine shales that overlie the Trenton Limestone. Those of
the Birkhill shales agree almost species for species with the fossils
of the Coniston Mudstone of Cumberland, the Kiesel Schiefer of
Thuringia, and the Lobiferous beds of Sweden, which lie at the
summit of the Lower Silurians of their respective countries. Hence
it may be considered certain that the Glenkiln shales are of highest
Llandeilo age, that the Hartfell shales stand in the place of the Bala
or Caradoc of Siluria, and that the Birkhill shales correspond to the
Lower Llandovery.

The insignificant thickness of these three formations in the Moffat
district is in strict agreement with the well-known north-westerly
attenuation of the Lower Silurian rocks in Wales, England, and in
Western Europe generally.

It was pointed out that these results, when carried to their
legitimate conclusion, harmonize all the apparently conflicting facts
hitherto collected among the Lower Silurians of the south of Scot-
land. We have a complete explanation of such difficulties as the
remarkable lithological uniformity of the predominating strata, the
absence of associated igneous rocks, the peculiar localization of the
fossils, their identity along certain lines, and their rapid and
peculiar impoverishment along others. We reduce, at a single
stroke, the apparently gigantic thickness of the South Scottish
Silurians to reasonable limits, and at the same time bring them into
perfect harmony with those of Western Europe and America.

II.—December 5, 1877.—Prof. P. Martin Duncan, M.B., F.R.S.,
President, in the Chair. The following communications were
read :—

1. “On the Building-up of the White Sinter Terraces of Roto-
Mahana, New Zealand.” By the Rev. Richard Abbay, M.A., F.G.S.

The author described the structure and mode of formation of the
so-called ‘‘ White Terrace” of the Roto-Mahana, which is produced
by a deposit of silica from the water of a geyser situated on the side
of a small hill of rotten rhyolitic rock, about 100 feet above the
surface of the warm lake (Roto-Mahana), into which the water from
the geyser finally flows, and the foot of the siliceous terrace projects.
The geyser basin, which is between 800 and 400 feet in circum-
ference, has steep walls broken through only on the side towards
the lake, where the water flows down to form a succession of
terraces, which are really shallow basins, over the outwardly in-
clined edges of which the water flows, depositing the dissolved silica
in a white subflocculent form on the edges and bottoms of the
basins in proportion as the water cools. The author showed how
this arrangement produced the peculiarly formed siliceous deposit of
the terraces, and that as the growth of the latter is evidently up-

46 Reports and Proceedings—

wards as well as outwards, it seems probable that the geyser pipe
has slowly worked its way up the hill by the solvent action of the
heated water from the level of the lake to its present elevation.

2. “Additional Notes on the Dimetian and Pebidian Rocks of
Pembrokeshire.” By Henry Hicks, Esq., F.G.S.

The additional facts communicated by the author show that at a
distance of about 10 miles to the east of the Dimetian axis of St.
David’s there is another ridge of these rocks, which also runs nearly
parallel with it. This is also flanked by Pebidian and Cambrian
rocks, and made up of rocks like those in the St. David’s axis.

The Dimetian formation, so far as it is at present known, consists
chiefly of the following rocks :—

1. Quartz porphyries, containing frequently perfect quartz crys-
tals (double pyramids), subangular masses of quartz, and crystals of
felspar in a felspathic matrix.

2. Fine-grained greyish quartz-rocks, very compact, and inter-
stratified with the above.

3. Ashy-looking shales of a dull green colour, sometimes highly
indurated, but usually showing lines of lamination. Microscopi-
cally these show basaltic characters, and are probably greatly altered
interbedded basaltic lavas.

4, Compact granitic-looking rocks.

5. Quartziferous breccias.

6. A series of compact quartzites and crystalline schists. inter-
stratified by green and purple altered basaltic lavas, with a slaty
and schistose foliation, and by some dolomitic bands.

Of the Pebidian formation new areas were added, and the portions
described in the author’s previous paper were further extended, and
details as to the chief mineralogical characters added. At the base
of the series resting unconformably on the Dimetian is seen an
agglomerate composed of large angular masses of a spherulitic
felstone, pieces of quartz and quartzites, indurated shales, crystalline
schists, ete., cemented together by a sea-green matrix of felstone.
These are followed by conglomerates of the same materials, which
are again succeeded by indurated shales, often highly porcellanitic
in character, with a conchoidal fracture.

These are followed by a thick series of silvery white and purplish
shales and green slates, alternating with fine and rough ashes, often
conglomeratic, hornstone breccias, felstone lavas, ete.

The series, as exhibited at St. David’s, has a thickness of over 8000
feet ; and as it is everywhere, so far as yet seen, overlapped uncon-
formably by the Cambrians, it may probably be of much greater
thickness. It evidently consists very largely of volcanic materials,
at first derived from subaerial, but afterwards from submarine vol-
canos. These materials, however, were also undoubtedly consider-
ably aided by sediments of a detrital origin.

The whole series shows that the sediments have undergone con-
siderable changes, but yet not sufficient to obliterate the original
characters, and the lines of lamination and bedding are usually
very distinct. That they were altered nearly into their present state

Geological Society of London. AT

before the Cambrian sediments were deposited upon them is clear
from the fact that the pebbles of the Cambrian conglomerates which
rest immediately on any portion of the series are almost invariably
made up of masses of the rocks below, cemented by gritty materials
on an unaltered matrix, and from which the pebbles may be easily
removed. The great conglomerates at the base of the Cambrians,
everywhere in Wales, indicate that there were beach- and shallow-
water conditions over those areas at the time, and that the sea was
then encroaching on an uneven land, becoming gradually depressed
to receive the subsequent Cambrian sediment.

3. “On some Precambrian (Dimetian and Pebidian) Rocks in
Caernarvonshire.” By Henry Hicks, Esq., F.G.S.

In this paper the author gave an account of the special examina-
tion of the great ribs of so-called intrusive felspathic and quartz
porphyries which are found associated with the Cambrian rocks in
Caernarvonshire, made by him in company with Prof. Hughes, Mr.
Hudleston, and Mr. Homfray last summer. He described sections
at and near Moel Tryfaen and across the mass from Pen-y-groes to
Talysarn, in which ke showed that instead of being of an intrusive
nature, as hitherto supposed, the whole, with the exception of a few
dykes at those parts, is made up of bedded volcanic rocks, lavas,
breccias, etc., similar to those found in the Pebidian series at St.
Davyid’s, and that the Cambrian rocks, instead of being intruded by
this mass, rests everywhere upon it unconformably, and the pebbles
in the conglomerate of the Cambrian at the base are, as at St.
David’s, identical with, and must have been derived from the rocks
below. Similar results were obtained in the examination to the
north and south of Llyn Padarn, and the conclusion, therefore, at
which the author has arrived with regard to the great mass which
extends from Llanellyfine in the south of St. Ann’s chapel in the
north is that it is entirely Precambrian, and that it belongs to the
series described by him under the name Pebidian at St. David’s.

The other mass, extending from Caernarvon to Bangor, he con-
sidered also entirely Precambrian; and from the mineral characters
exhibited by a portion of this mass directly behind Caernarvon, he
thought it would prove to be, at least at this part, of Dimetian age.
The altered beds near Bangor and their associated quartz felsites he
considered entirely of Pebidian age, as there is no evidence that the
Dimetian rocks are exposed there.

4. “On the Precambrian Rocks of Bangor.” By Prof. T. McKenny
Hughes, M.A., F.G.8.

The author described a series of slates, agglomerates, and por-
phyritic rocks which, near Bangor, are seen to pass under the Cam-
brian and seem to rest conformably upon the quartz felsites and
granitoid rocks of Caernarvon. He thought that the Bangor beds
were the equivalents of the felsitic and porphyritic series of Llyn
Padarn, and, in order to bring his interpretation into harmony with
the observations of Prof. Ramsay, he explained away the apparent
melting of the ends of the Cambrian beds in that section by twists,
faults, and dykes. He referred the apparent unconformity recorded

48 Correspondence—Ur. A. B. Wynne.

by Mr. Maw entirely to rock structure, produced by cleavage on
beds of different texture.

He considered that in the main the Bangor beds were the equi-
valents of the Pebidian of Dr. Hicks, while the Caernarvon beds
nearly represented his Dimetian. But he thought there was as yet
no proof of an unconformity between these formations. He would
explain the apparent unconformity at St. David’s by a continuation
of bends and faults and joints mistaken for bedding, and would refer
the brecciated rock of Low Moor, near St. David’s to the Pebidian,
thus taking it on the wrong side of the supposed unconformity. He
thought that the green beds in the Dimetian were, in all the cases
where he had been able to examine them, originally dykes.

He saw, therefore, no reason, from an examination of other areas,
to suspect any different explanation from that suggested by the ex-
amination of the Bangor and Caernarvon district, viz. that we have
in the Bangor and Caernarvon beds one great volcanic series, on
which the Cambrian conglomerates and grits rest with a probable
unconformability.

An appendix by Prof. Bonney, on the microscopical examination
of the rocks referred to, accompanied this paper.

(DOs ses svat IS OANf ID ADANKOsAa

SERED ca 3k
“CONCRETIONARY BANDS” OR “CONGLOMERATES” OF LAMBAY
ISLAND.

Str, —In the paper ‘“‘On the Borrowdale Series, and Coniston
Flags,” in the Quarterly Journal of the Geological Society for Aug.
1877, p. 479, the authors speak of “Concretionary bands” “called
by ” the late “Mr. Du Noyer, coarse conglomerates,” and according
to the late Prof. Jukes, containing “pebbles” with Silurian corals
attached. In next page these “conglomerates” or “ concretionary
bands” are said to form a portion of an ash-breccia series, but no
reason is given for what would seem to be an entirely unnecessary
correction of the descriptions quoted from Mr. Du Noyer and Prof.
Jukes ; nor is it stated why the rocks are referred to as ‘‘concre-
tionary bands.”

These descriptions, quoted at p. 479, will of themselves show the
difficulty of accepting the concretionary nature of the Lambay rock
referred to; the matrix being of “black mud,” inclosing pebbles of
“cleaved slate,” ‘grey grit,” ‘grey limestone,” “ greenish-grey
greenstone,” “ash,” and “limestone conglomerate inclosing rolled
pebbles of greenstone”: some of these fragments supporting attached
Silurian corals.

The unqualified application of the word “concretionary,” as an —
amendment to Mr. Du Noyer’s “coarse conglomerate,” to such rocks,
seems a singular use of the term, though it can scarcely be meant to
convey the idea that the writers quoted did not know the difference
between concretionary rocks and conglomerates.

A. B. Wynne.
Murreez, Oct. 1877.

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THE

GEOLOGICAL MAGAZINE.

NEW) SERIESa we DECADE itm V Ole nV

No. IIL—FEBRUARY, 1878.

@E= GaN Atay Aes alae Gale a Se

l.—Tue Orp Man or Hoy.
By Prof. ARcHIBALD GEIx1z, LL.D., F.R.S.,
Director of the Geological Survey of Scotland.
(PLATE II.)

TA\HE tidal wave of travellers which, thanks to railroads and

steamboats, pours northward over the country every summer,
even as far as John o’ Groat’s, has hardly as yet risen much beyond
that utmost shore. The tourist stops short at the Pentland Firth; —
indeed, when he reaches its bare treeless coast, and finds that there is
really no traditional house at John o’ Groat’s (though a good inn,
with careful host and kindly hostess, should tempt him to rest there
a while), he is in a hurry to get back by daylight to the busy hum
of men in the hyperborean city of Wick or Thurso, and as eager
to flit southwards again next morning. He makes a fatal mistake,
however ; for he misses the very points which it would have been
worth his while to make the whole of his long journey to see. Let
him, for instance, take up his quarters for a day or two by the side
of the Pentland Firth, and sitting or lying on one of its grim cliffs,
let him spend his hours watching the race of its tideway. Nowhere
else round the British Islands can he look down on sucha sea. It
seems to rush and roar past him like a vast river, but with a flow
some three times swifter than our most rapid rivers. Such a broad
breast of rolling eddying foaming water! Even when there is no
wind, the tide ebbs and flows in this way, pouring now eastwards
now westwards, as the tidal wave rises and falls. But if he should
be lucky enough to come in for a gale of wind (and they are not
unknown there in summer, as he will probably learn), let him by no
means fail to take up his station on Duncansbay Head, or at the
Point of Mey. The shelter of a flagstone “dyke” and a water-
proof will save him from any ulterior consequences of the exposure,
or should he be under some misgivings on this point, when he gets
back to the shelter of the inn at John o’ Groat’s, mine host has
sundry specifics of well-tried potency, at the very sight and taste of
which rheums, catarrhs and the rest of that tribe of ailments at
once decamp. Ensconced in his “ neuk,” he can quietly try to fix in
his mind a picture of what he sees. He will choose if he can a
time when the tide is coming up against the wind. The water no
longer looks like the eddying current of a mighty river. It rather

DECADE II.—VYOL. V.—NO. II. 4

50 Prof. Getkie—The Old Man of Hoy.

resembles the surging of rocky rapids. Its surface is one vast sheet
of foam and green yeasty waves. Hvery now and then a huge
billow rears itself impatiently above the rest, tossing its sheets of
spray in the face of the wind, which scatters them back into the
boiling flood. Here and there, owing to the configuration of the
bottom, this turmoil waxes so furious that a constant dance of
towering breakers is kept up. Such are the terrible “Roost of
Duncansbay.” and the broken water grimly termed the “‘ Merry men
of Mey.” With a great gale from the north-east or south-east, the
shelter even of the stone wall on Duncansbay Head would be of
little avail. For solid sheets of water rush up the face of the cliffs
for more than 100 feet, and pour over the top in such volume,
that it is said they have actually been intercepted on the landward
side by a dam across a little valley, and have been used to turn a
mill. Should the meditative tourist be overtaken by such a gale,
he will find shelter in the quaint cottage of the kind-hearted but
hard-headed John Gibson, who, perched like a sea-eagle at the head
of a tremendous chasm in the cliffs, can spin many a yarn about the
_ tempests of the north.

No one can see such scenes without realizing, as he probably has
never done before, the restless energy of nature. His eyes are opened.
He feels how wind and rain, wave and tide, are leagued together,
as it were in spite of their apparent antagonism, to batter down the
shores. Everywhere he witnesses proofs of their prowess. Tall
gaunt stacks rise out of the waves in front of the cliffs of which
they once formed a part. Yawning rents run through them from
summit to base; their sides are frayed into cusp and pinnacle that
seem ready to topple over when the next storm assails them; their
surf-beaten basements are pierced with caverns and tunnels into
which the surge is for ever booming. On the solid cliffs behind, the
same tale of warfare is inscribed. But the traveller who has seen
so much will perforce desire to see more. From his perch on the
southern side of the foaming Pentland Firth he looks across to the
distant hills of Hoy—the only hills indeed which are visible from
the monotonous moorlands of northern Caithness, save when from
some higher eminence one catches the blue outline of Morven on
the southern sky-line. The Orkney Islands are otherwise as tame
and as flat as Caithness. But in Hoy they certainly make amends
for their general featureless surface. Yet even there it is not the
interior, hilly though it be, but the western coast-cliffs which
redeem the whole of the far north of Scotland from the charge of
failure in picturesque and impressive scenery. One looks across
the Pentland Firth and marks how the flat islands of the Orkney
group rise from its northern side as a long low line until westwards
they mount into the rounded heights of Hoy, and how these again
plunge in a range of precipices into the Atlantic. Yellow and red
in hue, these marvellous cliffs gleam across the water as if the
sunlight always bathed them. They brighten a grey day, and grey
days are only too common in the northern summer; on a sunny
forenoon, or still better on a clear evening, when the sun is sinking

Prof. Geikie—The Old Man of Hoy. 51

beneath the western waters, they glow and burn, yet behind such a
dreamy sea-born haze, that the onlooker can hardly believe himself
to be in the far north, but recalls perhaps memories of Capri and
Sorrento, and the blue Mediterranean. Looking at them from the
mainland, we are soon struck by one feature at their western end.
A strange square tower-like projection rises behind the last and
lower spur of cliff which descends into the sea. We may walk mile
after mile along the Caithness shore, and still that mysterious mass
keeps its place. As we move westwards, however, the higher cliffs
behind open out, and we can see on a clear day with the naked eye
that the mass is a huge column of rock rising in advance of the cliff.
Itis the Old Man of Hoy—a notable landmark, well deserving its fame.

Let no tourist who has got up as far as Thurso hesitate to cross
the Firth and reach Stromness in Orkney. He will find a steamer
ready to carry him thither in a few hours, and in the voyage will
pass close under the grandest cliff in the British Islands. Above all
he will make the personal acquaintance of the Old Man, or at least
will be brought so near as to conceive a very profound respect for
him. The accompanying vignette was sketched from the vessel in this
passage, and though by no means taken from the most picturesque
point of view, may serve to convey some notion of the form and size
of this the most remarkable feature in Orkney scenery. The Old Man
is a column of yellow and red sandstone more than 600 feet high.
It stands well in front of the cliff, with which however it is still
connected by a low ridge of ruined blocks. Doubtless one main
cause of its impressiveness lies in the fact that its summit is con-
siderably higher than the cliff behind it. Thus it stands out against
the sky even when seen from a distance. Its base is washed on
three sides by the waves, which rise and fall over a low reef running
out from underneath the base of the column. Formerly a huge
buttress, like the Giant’s Leg of Bressay in Shetland, used to pro-
ject into the sea. But it has been swept away and for many years
the Old Man has had to keep his watch and wage his battle with the
elements with the support of but one leg.

Unless the ground-swell be too heavy, the steamboat usually keeps
close enough to the base of the great precipices to allow the masonry
of this wonderful obelisk to be distinctly seen. Like the cliff
behind, it is built up of successive bars of sandstone forming
portions of horizontal or very gently inclined strata. Its base, how-
ever, rests on a pedestal of different materials, consisting of two
well-defined bands, both of which can be traced stretching landwards
and passing under the base of the cliff. The lower of these two
bands is plainly marked by lines of parallel stratification inclined at
a considerably higher angle than the dip of the sandstones, and
evidently composed of something quite different from them. Viewed
thus from the sea in a brief and passing way, the column can be
recognized as composed of at least two very distinct portions. The
main pillar rests unconformably upon a platform of older and tilted
strata.

It is only when one lands on the island of Hoy, and examines the

52 Prof. Geikie—The Old Man of Hoy.

cliffs in detail, that the true nature and history of the threefold bars of
the Old Man can be made out. The yellow and red sandstones are
then found to present the ordinary characters of the Upper Old Red
Sandstone, to which they are with probability referred, though as
yet they have yielded no fossils. Irregularly alternating in thick and
thinner beds, they are rent by innumerable perpendicular joints.
By means of these divisional lines, slice after slice falls away from
the face of the cliffs, which thus maintain their precipitous front
towards the Atlantic. Except in regard to their scenic features,
these sandstones, however, are less full of interest than the two bars
of the Old Man’s pedestal. The upper bar consists of a band of
dark amygdaloidal lava with a slaggy surface. The same rock
appears elsewhere, rising out from beneath the sandstones of the
precipices, particularly at the north-western headland, where it con-
sists of three or more distinct bands with well-stratified volcanic
tuffs. To the north-east of that headland, on a tract of lower ground
intervening between the base of the hills and the edge of the sea,
several well-marked volcanic “ necks” or pipes occur, representing
some of the vents from which the streams of lava and showers of
ash were poured. The complete interstratification of the beds of
erupted material with the lower portion of the sandstones proves that
the volcanic action showed itself at the beginning of the deposition
of the Upper Old Red Sandstone in this region. Another little vent
may be observed on the Caithness coast, near John o’ Groat’s House ;
perhaps some may still remain to be noticed among the central and
northern members of the Orkney Islands. It seems to have been a
singular and local outburst of volcanic energy during Upper Old
Red Sandstone times—the only one yet discovered to the north of
the Highlands. The uppermost bar then of the pedestal on which
the Old Man has taken his stand is a massive sheet of lava.

The lower bar belongs to a very different period, and has a totally
dissimilar history. On looking more closely into the strata which,
even seen from the sea, plainly lie unconformably below the lava
and its overlying sandstones, we find that they consist of dark thin-
bedded sandstones, shales and impure limestones. In short, they
are a portion of the great series of deposits known as the Caithness
flagstones. On many of their exposed surfaces shining jet-black
scales, bones and teeth of the characteristic fishes of these flag-
stones may be noticed. What a suggestive picture of the imper-
fection of the geological record is presented to us by some of these
weather-beaten or surf-worn sheets of rock! We pick up from
their crannies the broken whelks, nullipores, and corallines, tossed
up by the last storm from the zones of life now tenanting the sea
below us. The limpet and sea-anemone, the whelk and barnacle,
are clinging to the hardened sand over which the Osteolepis and
Coccosteus and their bone-cased brethren disported in the ancient
northern lake of Lower Old Red Sandstone times. Nay, we may
now and then watch a living molluse creeping over the cuirass of a
paleozoic fish. Yet who can realize the lapse of time which here
separates the living from the dead ?

Prof. Geikie—The Old Man of Hoy. O38

Below and beyond the horizon of the flagstones no evidence among
the Hoy Cliffs remains to lead us. But in the neighbouring isles of
Pomona and Gremsa, bosses of crystalline rocks—granite, gneiss
and schists—project from under the flagstones. They are wrapped
round with conglomerates, doubtless representing the shore-gravel
heaped up around them when they rose as islets out of the Old Red
Sandstone lake.

So much for the materials out of which the Old Man has, been
carved. And now a few words as to the process of carving. If
the traveller who has reached Stromness finds himself with even
one spare day at his disposal, he cannot employ it to more con-
spicuous advantage than by taking a boat with a couple of stalwart
Norse-like Oreadian boatmen, crossing the strait to Hoy, and ascending
that island by the Cam and the north-western headland, until he
finds himself at the summit of the great western precipice with the
surface of the surging Atlantic some 1300 feet below him. The
scene tells its own tale of ceaseless waste, and needs no lecture
or text-book for its comprehension. Pinnacles and turrets of the
richly-tinted sandstone roughen the upper edge of the cliff, often
fretted into the strangest shapes, and worn into such perilous
narrowness of base that they seem doomed to go headlong down
into the gulf below when the next tempest sweeps across from the
west. Butresses, sorely rifted and honey-combed, lean against the
main cliff as if to prop it up ; but separated from it by the yawning
fissures which will surely widen until they wedge off the projecting
masses, and strip huge slices from the face of the cliff. One sees
as it were every step in the progress of degradation. It is by this
prolonged splitting and slicing and fretting that the precipice
has been made to recede, and has acquired its shattered but
picturesque contours. The Old Man is thus a monument of the
retreat and destruction of the cliffs of which it once formed a part.
To what accidental circumstance it may have owed its isolation, we
may not be able to say with certainty. But it is suffering in the
prevalent decay. Every year must insensibly tell upon its features.

On the calmest day some motion of air always keeps playing
about the giddy crest of these precipices, and a surge with creaming
lines of white foam meets at their base. But when a westerly
gale sets in, the scene is said to be wholly indescribable. The
cliffs are then enveloped in driving spray torn from the solid sheets
of water which rush up the walls of rock for a hundred feet or
more, and roll back in thousands of tumultuous waterfalls. The
force of the wind is such as actually to loosen the weathered parts
of the rock and dislodge them. Thus along the mossy surface of
the slope which ascends inland from the edge of the cliff, large flat
pieces of naked stone may be picked up by scores lying on the
heather and coarse grass, whither they have been whirled up from
the shattered crags by successive gusts of the storms.

The destruction of this coast-line has not yet, however, wholly
effaced traces of other powers of waste which have long since passed
away. On the very edge of the cliff, to the south-east of the Old

54 Prof. Dr. Ferdinand Roemer—A. Visit to Ireland.

Man, some well-preserved striations on the sandstone point to the
movement of the ice-sheet of the glacial period across even the hilly
island of Hoy-in a N.W: and 8.E. direction. Again in the green
corry at the Cam of Hoy, some beautifully perfect little moraines
remain to show that after the great land-ice had subsided, the snow-
fall in these northern regions continued heavy enough to nourish in
so small an island as Hoy groups of valley glaciers. Though the
general form of the hills and valleys remains now much as it was
when the last lingering glacier melted away, there have been
stupendous changes since then in the shaping of the précipices. At
that time the Old Man still formed a portion of the solid cliff. It is
in the ensuing interval that this impressive landmark has been left
during the destruction of the surrounding masses. Long may he be
able to stand his ground! When his last hour comes, as come it
must, may some reverential geologist, duly impressed with a sense
of the potency of denudation in the relief of the land, be there to
pay the last honours to his dust !

IJ.—Gerotocican SKetcH oF A Visit To InELAND In Avcust, 1876."
By Dr. FERDINAND RoEMER,
Professor of Mineralogy in the University of Breslau.

HAVE been this autumn in the Land of the Giant’s Causeway
and of the Giant Stag. For a long time it had been my earnest
desire to become acquainted with “The Green Isle.” In my
colleague, Professor von Lasaulx, I found a wished-for companion
on my journey. It is easy to get to Ireland. In a single night’s
journey one is whirled from London to Dublin wid Holyhead.
In Dublin the best directions for a geologist are to be had at the
Geological Survey Office for Ireland, which forms a department of
the Government Geological Survey of Great Britain. Prof. Hull, the
Director of the establishment, and Mr. Hellier Baily, the Paleeon-
tologist attached to it, afforded me, with the greatest kindness, every
necessary assistance. Besides these two gentlemen, who reside in
Dublin, the Geological Survey includes a number of other geologists
scattered through the country, who carry out its purposes. A large
portion of Ireland is already surveyed, and the maps containing the
results for the most part published. Explanations of these maps
appear under the title of “‘ Memoirs of the Geological Survey.” The
last part that was published this year bears the title: ‘ Explanatory
Memoir to accompany Sheets 21, 28, and 29 of the Maps of the
Geological Survey of Ireland, including the Country around
Antrim, Larne, and Carrickfergus, by Edward Hull, Director,
with Paleontological Notes by W. H. Baily, Dublin, 1876.” This
part treats of one of the most remarkable districts of the North of
Ireland. Several years ago a good general geological map of
Treland was published by the late Professor Jukes, then the dis-
tinguished Director of the Survey, the title being : “ Geological Map
of Ireland, by Joseph Beete Jukes (EH. Stanford, London), 1864.”

* From the Neues Jahrbuch fiir Mineralogie, Geologie und Palaontologie, Jahrgang
1877. Translated from the German by Richard J. O. Mulrenin.

Prof. Dr. Ferdinand Roemer—A Visit to Ireland. 50

Since the first appearance in 1865 of the Journal of the Royal
Geological Society of Ireland (new series), it has been issued
regularly, and contains many important geological articles on the
country. The Transactions of the Royal Irish Academy contain some
interesting papers on geology and paleontology, as, for instance,
Professor T. H. Huxley’s and Dr. Percival Wright’s description of
remarkable reptiles in the Coal-measures of the Co. Kilkenny (“On
a Collection of Fossil Vertebrata from the Jarrow Colliery, County
Kilkenny, Ireland,” vol. xxiv. 1867).

Several public collections in Dublin are important in a geological
sense. We may mention in the first place the Museum of the
Royal College of Science. Here are to be found in a large gallery
on the upper floor the collections of the Geological Survey. They
comprise beautiful series of Irish rock-specimens, and of the
fossils of the several sedimentary formations. Among the latter
especially are splendid examples of the Palcopteris Hibermca,
Schimp. (Adiantites Hibernicus, R. Griff. and Ad. Brongn.), from
the upper division of the Old Red Sandstone, or Devonian beds,
particularly that which contains the Yellow Sandstone of Kiltorkan
Hill, in the Co. Kilkenny, as well as from the other formations con-
taining remains of vegetable and animal life. Moreover, there are
rich collections of fossils from the Carboniferous Limestone, which, of
all the sedimentary formations in Ireland, occupies the largest space.
From the upper or productive Coal-measures are some of the
originals of the remarkable reptiles already referred to as described
by Professor Huxley and Dr. Percival Wright. A complete skeleton
of the Cervus megaceros is a conspicuous ornament to the hall. The
Museum of the Royal Dublin Society, which is under the excellent
management of Dr. A. Carte, contains also much that is really
remarkable. The principal ornament of this collection consists in
the complete and original specimen of the Plesiosaurus Cramptoni,
the largest of the species yet discovered, which was found in the
Lias of Whitby. The specimen of Didus ineptus, complete all but the
skull, which has been artificially supplied, is likewise exceedingly
interesting. Numerous remains of this extinct bird were found a few
years ago in draining a swamp in the island of Mauritius; an event ~
which makes the conjecture probable that, in the course of time, several
more specimens of this singular bird may be brought to Europe.
There are besides in this Museum complete skeletons of the Cervus
megaceros, male and female. On beholding these, one cannot avoid
wishing that a few living examples of this majestic animal, which
must have thrown into the shade all other species of the beautiful
deer tribe, had continued to exist in our present world.
Several heads with the antlers, and numerous bones, of the same
magnificent animal, are likewise exhibited. Some of the latter
present the singular appearance of being marked with deep cuts or
indentations, which, on account of their sharpness and smoothness,
one would naturally suppose to be the effect of a sharp tool worked
by human agency, if the well-observed circumstances under which
these marked bones and organic remains were discovered did not

56 Prof. Dr. Ferdinand Roemer—A Visit to Lreland.

refute this supposition. These appearances were, for the first time,
described by Professor Jukes in 1863 (‘On some indentations in
bones of a Cervus megaceros, etc.,” Journ. Geol. Soc. Dublin, vol. x.,
pt. 2, p. 127 et seq.), and afterwards by Dr. Carte (‘‘On some
indented bones of the Cervus megaceros, found near Lough Gur,
County of Limerick,” Journ. Geol. Soc. Dublin, vol. i., pt. 2, 1865—
1866, 2nd series, p. 151 ef seq.), who further explained and illus-
trated them. Both observers have demonstrated that wherever
such portions of skeletons have been observed to be marked in situ,
a bone fitting into the indentation has been found with it in such a
position that its motion to and fro would at once explain the cause
of the indentation. The only doubt remaining was as to the origin of
the motion of friction backwards and forwards. Dr. Carte believes
that the effect must have been caused by the rising and sinking of
the bog in the long course of ages, the peat having been alternately
contracted by the dryness of summer and expanded by the damp
and wet of winter. This remarkable phenomenon deserves par-
ticular attention, as it shows how effects are produced through the
agency of inanimate nature, which, on superficial observation, may
be easily accepted as having been caused by the agency of man.
Finally, the same Museum also contains the greater part of the
extensive collection made by Sir Richard Griffith, of the Car-
boniferous Limestone and Silurian fossils of Ireland. These
collections have been described by Professor McCoy. The
original specimens of the remarkable genus Palechinus particularly
arrested my attention. Sir Richard John Griffith, the constructor of
the first Geological Map of Ireland, and who has done so much for
the geology of that country, is still living in Dublin at the great age
of 92 years. I did not fail to call upon him to express to him my
deep respect. He related to me what difficulties he had to overcome
when he first began to construct his maps, at a time when there
were scarcely decent roads through the country, much less railways,
and he had himself to obtain the topographical information which
was to serve as a foundation for his geological undertakings.

A third collection worthy of a visit is that of Trinity College.
It is arranged in a large hall belonging to the range of magnificent
buildings composing this institution. Here also several skeletons
of the Cervus megaceros at once arrest the attention, and particu-
larly a male, of extraordinary size. There are also several other
skeletons, including that of a female. The latter is readily dis-
tinguishable, as is the case with several other species of deer, by
being hornless, the reindeer forming an exception; this fact was at
one time doubted. The hornless skulls of the females naturally
attracted less notice’ on the part of the uneducated finders than
those of the males, and on that account remained a long time un-
known. Besides the above, there are some valuable specimens of
fossils, minerals, and precious stones.

Some excursions in the immediate and more distant environs of

} They were generally supposed by the Irish labourers to be the skulls of horses,
and so were thrown aside.

Prof. Dr. Ferdinand Roemer—A. Visit to Ireland. 57

Dublin afforded a variety of information. One of them related to
the presence of Posidonomya Becheri at Loughshinny near Rush,
to the north of Dublin. Black shales sometimes passing into
hard limestone, traversed by veins of quartz, are numerous on
this part of the coast. Some of these strata have their surfaces
covered with the shells of Posidonomya Becheri. The appearance
of the whole strikingly resembling that. of Barnstaple in Devon-
shire (the Lower Culm Beds of Murchison). Here, in Ireland,
however, the layers of rock containing Posidonomya are in
closer connexion with the principal mass of the Carboniferous
Limestone which is to be seen in the immediate neighbourhood,
where extensive quarries are worked, while in Devonshire the Car-
boniferous Limestone is wholly wanting, and the Posidonomye are
found there in the Culm formation which takes its place. At
numerous other points, likewise, the Irish geologists have met with
the same mollusc with similar distinguishing marks. It is further-
more found in the Coal-measures of Northumberland in precisely the
same circumstances. It is a matter of great interest to determine
the exact horizon which the Posidonomya Becheri occupies in the
Coal-measures of Ireland and England, because it will then be
possible to determine to what division of the Carboniferous Lime-
stone our German sandstone Culm formation corresponds, this being
palzontologically characterized by the same mollusc. I have during
my journey collected a number of facts bearing upon this point,
which I shall publish on a future occasion.

The Irish metropolis and its environs having been visited, there
succeeded longer excursions into more distant districts of the
island. The first one was to the charming Lakes of Killarney,
so celebrated for their picturesque beauty. They are situated in the
County of Kerry, which occupies the south-western corner of
Ireland. In order to get to this district, one is obliged to traverse
the whole of the southern half of Ireland from north-east to south-
west. The journey is for the most part rather monotonous, but not
disagreeable ; it proceeds over the great central plain, the foundation
of which is formed by horizontal or slightly inclined strata of Car-
boniferous or Mountain Limestone. But it is only occasionally that
the Carboniferous Limestone crops up at the surface. In most places
it is covered by a layer of gravel of greater or less depth. At times
this diluvial gravel, composed of water-worn pieces of limestone,
and partly also of other kinds of rocks, is raised into ridges or
eskers of moderate elevation. Thus the surface of the country is,
to a certain extent, undulating. The hollow flats which lie deeper
are, far and wide, covered with peat-bogs. On the whole the
country appeared to me by no means such a wilderness, nor so
badly cultivated, as I had imagined from the perusal of many
descriptions of it. The brilliant green of a rich sward, caused by
the great humidity of the climate, does not give the impression of a
desert or barren country.

Higher mountain summits first begin to appear in the southern
portion of the island. They are steep and rugged mountains from

58 Prof. Dr. Ferdinand Roemer—A._ Visit to Ireland.

2000 to 3000 feet in height, not wooded, which stretch through the
counties of Cork and Kerry from east to west as a strongly linked
chain. They consist of very steep banks of grey and reddish
sandstones, and quartz rocks of the Old Red formation. The charac-
teristic fossil fish found in this formation in England and Scotland
scarcely show a trace of their existence in the corresponding Irish
rocks. Igneous rocks of the porphyry class have broken through the
Old Red Sandstone at certain points. It is on the borders of the
Carboniferous Limestone, and between it and the Old Red Sand-
stone, that the Lakes of Killarney are situated. The strata of the
former are here raised at a great angle, and towards the south occur
among those of the Old Red Sandstone as apparently later deposits.
The attractive feature of these lakes, which every year brings
thousands of visitors and sight-seers, depends principally on the
beautiful forms and mighty precipices of the Old Red Sandstone peaks,
which on the south surround these lovely sheets of water. At the
same time the lakes themselves, with their numerous islands and
rich clothing of verdure, are beautifully picturesque. This vegetation,
of a wonderfully luxuriant growth, favoured by an exceedingly mild
and humid climate, consists in part of evergreen plants, among which
is conspicuous the strawberry tree (Arbutus unedo, L.), otherwise con-
fined to the countries bordering on the Mediterranean. We ascended
Mangerton, which rises to a height of 2756 feet, from the summit
of which an extensive view over the lakes and their surrounding
country rewards the visitor. These mountains, however, clothed to
their tops with a thick garment of verdure, do not offer good subjects
for geological investigation. Mangerton is not by any means the
highest point of the Old Red Sandstone mountains, as Carrantuohil
(3474 ft.), lying further to the west, overtops it considerably.
Another excursion was undertaken from Dublin to the north-
west districts. The Earl of Enniskillen, whose researches on the
subject of fossil fishes have made his name known far and wide,
had the kindness, on ascertaining my presence in Ireland, to
invite me to his residence at Florence Court, near Enniskillen,
in order to inspect his celebrated collection. The town of
Enniskillen is situated at the southern extremity of Lough Erne,
in the Co. Fermanagh, and Florence Court is a few miles to the
south. For three days I enjoyed the proprietor’s hearty and
thorough hospitality at this magnificent demesne, while most
agreeably occupied under his guidance with the examination of his
collection. From every country, and out of every formation, are
gathered, in this magnificent collection (the result of forty years’
labour), the finest specimens of fossil fish. It has but one rival in
England, viz. Sir Philip Egerton’s collection at Oulton Park,
in Cheshire. Both the Earl and Sir Philip, connected for many
years by bonds of friendship and common studies, having had their
ichthyological tastes developed by Agassiz, have cultivated them
and made collections together. In many respects the one collection
forms the counterpart of the other. Florence Court is also well
known to palzontologists as the original locality for certain fossil

Prof. Dr. Ferdinand Roemer—A Visit to Ireland. 59

Crinoidea. The beautiful cups of the Actinocrinus amphora and of
several species of the genera Platycrinus, Pentremites, etc., which
are scattered though many collections, derive their origin from this
place and neighbourhood. The quarries in the Carboniferous Lime-
stone, from which these fossils were formerly obtained, are not,
however, worked any longer at present, and the place is accordingly
elosed up. With great difficulty only, could I obtain some small
examples of Pentremites Derbiensis, which appear on the weathered
surface of large blocks of limestone that are heaped up in wild con-
fusion under a steep limestone ridge.

From Enniskillen we directed our way northwards in order to
view the remarkable and abrupt termination of the basaltic field of
Co. Antrim, where it reaches the sea. This basaltic plateau, which
spreads over more than 800 square miles of the North of Ireland,
culminates in the Giant’s Causeway, which, however, is not for the
geologist its most remarkable termination. The railway leading to
it runs through Londonderry, and then in a north-easterly direction
as far as Portrush, a small town best known as a watering place.
The Giant’s Causeway is but a few miles distant from this. In the
immediate vicinity of Portrush several remarkable geological
phenomena are observable. A small rocky promontory is composed
of an igneous doleritic rock common in this district. At this
promonotory dark sedimentary strata, slightly inclined, show them-
selves on the surface of the sea-shore, forming reefs extending
seawards. These are banks of dark grey rock composed of in-
durated clays, harder in some places than in others. It was with
astonishment that we perceived certain strata of this rock filled
with Ammonites and other characteristic fossils of the Lias; for, from
the nature and position of the strata, one might have been inclined
to ascribe a far greater antiquity to them. The organic contents of
these strata indicate not only the presence of the Middle (?) and Lower
Lias, but layers of the Avicula contorta are visible, characterizing
the Rheetic formation. This shell, first described and figured from
the North of Ireland by Portlock, has since been recognized as an
important characteristic fossil at many places in Central Kurope.

Hastwards from Portrush these Jurassic rocks disappear, and the
White Chalk, overflown by the basalt, makes its appearance, forming
grand scenery, which would not only rejoice the heart of the
geologist, but must also attract the admiration of the ordinary
spectator. Masses of snow-white chalk-rock a hundred feet high
face the sea in perpendicular precipices, crowned by the sharply
contrasted black basalt. Belemnitella mucronata and other dis-
tinguishing fossils make the geological position of the White Chalk
certain. The boundary between chalk and basalt does not by any
means run quite horizontal, but rises and falls in hills and hollows,
evidently because the surface of the chalk at the time of its being
overflowed by the basalt was very uneven. And so it becomes
clear how further eastwards towards the Giant’s Causeway the chalk
disappears altogether, and the basalt descends to the level of the
sea. ‘The Giant’s Causeway is itself a small low promontory of

60 Prof. Dr. Ferdinand Roemer—A._ Visit to Ireland.

basalt washed by the waves, and during winter storms overflowed
by the sea. It is simply the regularity of its columns that has
made it celebrated. This regularity is particularly striking, as one
sees not only the prisms from the side, but, by going over their tops,
the broken ends, plainly showing the six-sided or polygonal sections.
This peculiarity distinctly characterizes the phenomenon. The
thickness of the columns, usually amounting to over a foot. corre-
sponds to the breadth of the crevices between neighbouring columns,
the spaces being mostly half an inch broad. The concavo-convex
jointings of the columns are frequently developed in great per-
fection. On the land side the Giant’s Causeway is bounded after
the manner of an amphitheatre by perpendicular walls of basalt
several hundred feet in height. Here, however, the regular
prismatic formation is absent. The rock being partly amygdaloidal,
and the cavities covered with various kinds of zeolites. Other-
wise, the basalt of Northern Ireland is altogether of the self-same
age with that of Germany and Central Europe, which is proved by
the occurrence with it of a layer of red clay containing impressions
of leaves of Miocene trees. Mr. W. H. Baily has particularly de-
scribed such a stratum exhibiting this kind of plant-growth in the
neighbourhood of the town of Antrim. It is only a few inches
thick, and rests proximately on a ten to twelve foot deep series of
strata holding lumps of iron-ore (“ Notice of Plant-remains from
Beds interstratified with the Basalt in the County of Antrim,” Quart.
Journ. Geol. Soc. 1869, vol. xxv. p. 162).

Having returned from the Causeway to Portrush, we pursued our
journey from the latter to Belfast. On the way thither we had to cross
in its entire length the great basaltic plateau of the North of Ireland.
It is almost a level or rather undulating district, on whose surface the
great dark blocks of basalt are everywhere scattered. But in the
neighbourhood of the town of Antrim there rises a group of hills
consisting of igneous rocks of an entirely different kind, and the
central point of these is the round bowl-shaped Tardree mountain,
a few miles from Antrim. Several quarries, in which the rock is
worked for economic purposes, are situated on its borders. It is a
light grey felspar rock, rich in quartz, and of the trachyte group.
Professor H. Hull, who has lately fully described its characteristics
(‘Memoirs Geol. Survey: Explanatory Memoir to accompany Sheets
21, 28, and 29 of the Maps of the.Geol. Survey of Ireland, including
the country around Antrim, etc., Dublin, 1876,” p. 17 e¢ seq.),
has named it Trachyte-porphyry, and J. Roth (Beitr. Petrogr.
pluton. Gest., 1873, p. xxxiil) places it among the liparite group,
following a published analysis by E. Hardman. According to Prof.
Hull, the rock is covered by basalt, and is considerably older than the
latter. We had not the opportunity of fully examining these con-
ditions of the strata on our flying visit to the quarries. The isolated
appearance of the rock in such a limited space is at any rate well
worth observation. In no other part of Ireland are trachyte rocks
known, [except to the west of Hillsborough, Co. Down. |

The environs of Belfast are also deeply interesting to the geologist.

Prof. Dr. Ferdinand Roemer—A Visit to Ireland. 61

This great manufacturing and business-like town, which is rapidly
increasing, and threatens soon to exceed Dublin in the number of its
inhabitants, lies at the edge of the great basalt plateau of the county
Antrim, which here, as on the north coast at Portrush, falls towards
the sea with a steep descent, and likewise covers the chalk and other
sedimentary strata. These characteristics are strikingly prominent at
Cave Hill, which is a steep and rugged mountain over a thousand
feet high (1188 ft.), and about an hour’s walk from the town. Here

again the White Chalk crops out from under the basalt, the latter .

not being of a distinct prismatic form, but generally taking the com-
position of amygdaloid. Hxtensive quarries, in which the basalt is
exposed, supply the finest views of its contact with the White Chalk,
the divisional line being very distinct, from the great contrast of
colour between the two rocks. It is not always horizontal, but runs
in many parts very irregularly, and the basalt in many places sinks
deep into the Chalk. Moreover, veins of basalt penetrate the Chalk
in various places. Under the White Chalk another division of the
Cretaceous formation is clearly observable, viz. a dark-green marly
Greensand, containing Hxogyra conica, Pecten asper, remains of Cal-
lianassa, and other fossils, by means of which it has been without
hesitation classified by British geologists with the “ Upper Green-
sand,” and by D’Orbigny with the ‘Htage Cenomanien.” At a
short distance from the quarries other sedimentary rocks show them-
selves ; the Lower Lias, the Rheetic, the Keuper, and the variegated
sandstone, “ Bunter Sandstein.” The Lower Lias is without any
doubt determined by Gryphea arcuata and other characteristic
species; the Rheetic is likewise distinguished paleeontologically ; the
Keuper, a succession of red and green marly slates, interspersed
with thin strata of sandstone containing mica and veins of gypsum,
is easily distinguished ; finally the variegated sandstone (“Bunter’’)
appears in the plain along the sea-shore as a red sandstone, the
boundaries of which on the side of the Keuper are often difficult
to determine. ~

Between the Lower Lias and the “ Cenomanien” Greensand all
the other members of the Jurassic and Chalk formation are wanting,
and accordingly the Upper Lias, the whole of the middle and upper
division of the Jurassic formation, both lower members of the Chalk
formation, the Neocomian and the Gault, are absent. The same
rule holds for the whole of Northern Ireland, and this wide gap in
the regular succession of the sedimentary strata is one of the most
remarkable phenomena of the geognostic constitution of the country.

With respect to the Keuper, it was a novelty to me to learn that
here this formation, as in Cheshire, and other parts of England,
contains massive beds of rock-salt. In the neighbourhood of Car-
rickfergus, to the northward of Belfast, a rock-salt pit (Duncrue)
has been worked for the last few years, from which, in the year
1873, there was obtained over 19,000 tons of rock-salt.

We should willingly have made a longer sojourn in this remark-
able country, especially for the purpose of visiting the granite of
the Mourne Mountains, south of Belfast, celebrated for their beautiful

ee

62 Prof. Milne—Across Europe and Asia.

crystallized minerals. Our time, however, was up. The opening of
the Meeting of the British Association in Glasgow, at which we
were anxious to be present, was about to take place, and if we
wished to avoid missing it, we were under the necessity, without
delay, of embarking in one-of the numerous steamboats plying
between Belfast and that great Scottish industrial town.

IIJ.—Across Evrorr anp Asta.—Travetiine Notes.
By Professor Joun Miunz, F.G.S.;
Imperial College of Engineering, Tokei, Japan.
(Concluded from p. 37.)
Part IX.—Through China, Kalgan, Pekin, Shanghai.

Contents.—Kalgan to Pekin—Geology of the district—Devonian Limestone—
Coal Measures—Granite—Alluvium—Degradation of Steep Mountains. Pekin
to Tiensin and Shanghai—Geology of the Country—Carboniferous Limestone—
Granite—Alluvial Plaim—lIts origin by deposition of river mud and elevation.

General Conclusion.

FTER much slipping and sliding—for the small stream of water
which flows down the pass had often glazed it from side to
side—we reached the village of Yamborshan, just outside the Kalgan

walls. Here I was well received by the Russian Postmaster, M.

Shismaroff. This village, like Kalgan itself, is romantically situated

in a defile, which is bounded by mountainous cliffs of a volcanic

rock, called by Pumpelly a porphyritic trachyte. Before entering

Kalgan, you pass underneath a gateway in the famous Great Wall

of China. Right and left from this point, it rapidly ascends to the

summit of the cliffs, which bound the defile, and its towers are seen
standing on pinnacles of rocks, and looking over precipices from
positions which seem inaccessible.

T left Kalgan on the 11th of December in a palanquin carried by
two mules on the road towards Pekin. The first day, although I
could see hills in the distance, I travelled over a flattish country
covered with a deposit of sandy alluvium. In places, this. formed
gorges with perpendicular walls 30 feet in height. Next morning
I crossed a boss of igneous rock, which was filled with veins of quartz
and calcite. Soon after this I met donkeys and mules carrying coal,
which told me I was entering a coal district. The first notice of
this was a mountain of greyish limestone, along the side of which
we travelled on a pathway cut out of the solid rock. After travers-
ing across the ice, which spanned a flooded plain, we came to
mountains of sandstone and shale, in which I saw several thin
vein-like seams of coal. On the sides of these mountains we saw
many old “dumps,” marking the site of ancient surface workings.

In the afternoon I saw some pinkish-looking granitic mountains
upon the left, and at this point the road became very stony, our course
being everywhere impeded by beds of boulders. These consisted of
porphyries, granites, felsites, and allied stones. Beyond this rough
track, our road passed along by a wall cut in the alluvium which
fills all the valleys, containing bivalve shells (Cyrena) to all
appearances exactly similar to some which I obtained from an ad-
jacent river.

Prof. Milne—Across Europe and Asia. 63

Harly next morning we entered the Nankan Pass, and after four
hours’ scrambling and sliding down over the bed of a frozen torrent,
which was bounded by bare rugged granitic mountains, we reached
the lower end of the defile, which, I think, presents the finest and most
romantic scenery between Pekin and St. Petersburg. At the lower
end of this pass, after passing the famous gateway of Kiiyungkwan,
you see the junction of a limestone rock with the granite, the latter
being overlain by the former. This limestone, together with that
which I have before mentioned, is supposed to underlie the Coal
formation, and to be of Devonian age—a view which is confirmed by
the Brachiopoda which are said to occur in it.

The country at the lower end of the pass I found to be very
bouldery, being covered with blocks of limestone and granite, which
had rolled down from the mountains. These gradually became less
and less, until we were at last upon a cultivated flat dusty plain,
over which we travelled until we reached Pekin on the 14th.

I have not said more about my journey from Kalgan to Pekin,
because this portion has been already described by Mr. Pumpelly in
the Smithsonian Contributions to Knowledge, No. 202, in considerable
- detail, to which I have but little if anything to add.

When looking at high rugged mountains like those I had just passed
through in the Nankan Pass, and like others which IJ had seen in other
parts of the world, as, for instance, in N.W. Arabia, it often occurred
to me that these mountains must be wearing away at an enormously
greater rate than others do where the inclination is not so steep.
Mechanical degradation, to which such mountains are subject, might
be considered as roughly measurable by the action of gravity
pulling particles to lower levels. A particle lying on a level plane
is not affected by this action, and there is no degradation. But
particles lying on inclined planes are pulled downwards, and the
steeper the plane the greater is the pull, and consequently the more
effective and rapid is the action. Thus, for instance, if we see a rock
balanced on the side of a steep mountain, we know that there is
more danger of its rolling down, and that when it does roll, it will
do so more rapidly than if it had been placed upon the side of a
hill which was comparatively less steep. This renders it danger-
ous to travel beneath a steep mountain, or through a deep cutting,
and this is one way of looking at the recognized fact that steep
mountains are degraded at a greater rate than those with slopes
more gentle.

In order to gain some conception of what these rates are in com-
parison with the slopes upon which they occur, we must consider
the conditions tending to accelerate or retard the downward pull of
gravity. Amongst the many points to be considered when com-
paring the degradation or falling down of material upon two slopes,
the following ¢ appear to be of importance :

Ist. The force tending to loosen any material lying upon the
surface of a mountain.

2nd. The circumstances under which material may obtain its
initial motion.

Sc a

64 Prof. Milne—Across Europe and Asia.

ord. The power that material when in motion has to roll to
lower levels, and to disengage other matter that it may meet
with in its descent.

Here we see three of the parts into which the subject divides
itself, and each of these has to be considered relatively to slopes of
varying inclination.

Part I.—The best way to look at Part I. is to take the simple cases of bodies
lying upon inclined planes. The force tending to pull the body down such a plane
is its weight (JV), multiplied by the sine of the angle (a) of the inclination of the
plane, or sin a; but as the inclination of the plane increases, sin a also increases :
therefore /V sin a increases. That is to say, if we have two bodies of equal weights
on planes differently inclined, the force tending to pull the body down the steeper
neve 8 greater than the force tending to pull the body down the plane which is less
inclined.

The reason of thus stating a self-evident condition is for the purpose of comparing
the relation existing between these forces on two different planes, which we see must
be proportional to sin a. Thus if we take planes with slopes of 10°, 20°, 30°, 45°, 60°,
and on each of these there rests a stone of weight WW, the force tending to pull this
stone down will be,

W sin 10°, W sin 20°, W sin 30°, Wsin 45°, and W sin 60°,
or W173, W-342, W-500, W-707, W -866.

From these few cases we see that for low slopes, say up to 30°, the force tending
to pull the stone downwards increases approximately proportionately to the angle;
that is, for double the inclination you get double the force; but on slopes of a steep
inclination, as compared with those of a low inclination, this rate of increase is not
so rapid; thus the force tending to pull a stone down on a plane of 60° is not six
times the force tending to pull a stone down on a plane of 10°.

This result will be much more strikingly illustrated if we take into account the
initial resistance to motion, where the force at starting will be W sin a—p W cos a,
# representing the initial resistance to motion, whether it is of the nature of friction
or the resistance offered to the breaking off of rocky masses.

Part II.—Before considering the effect that matter has when in motion down an
incline, we must recognize the fact that a stone when it obtains motion upon a steep
mountain, as in falling from a rock, the rolling over of a stone usually would obtain
more Kinetic energy at its start, than one upon a mountain of less inclination would.

Thus upon an inclined plane 4B, a particle falling from the summit of a rock ae
to the point 4 upon the plane 4B,
would usually have a much greater
height to fall upon a plane of steep
inclination, than it would upon one
where the inclination was more mode-
rate, and therefore at its starting to
roll towards B, would also have more
energy.

Calling ab=h; ac=K; the in-
clination of the plane=a; then /=
K sec a, from which we see the rocks
upon two different planes being
similar, or ae being constant, then

this height varies as the secant of the angle of the inclination of the plane. There-
fore a rock thus starting in a manner analogous to that considered, either by tumbling
forward or actually falling, has at the commencement of its course more energy to
do work as a stone in motion—this energy varying as the secant of the angle of in-
clination of the plane. x ;

Part III.—The power that a stone has in rolling to lower levels and overcoming

obstacles in its passage over the sides of two mountains which differ only in inclina-
tion, might be compared by the distance they relatively travel. It is evident one on
a steep slope would tend to roll farther than one on a gentle slope, and the vertical
distances down which these blocks would travel before coming to rest would measure
‘the relative rates of this sort of degradation,—because the mountain which rolled
its material farthest down would tend to become level the quickest.

Prof. Miine—Across Europe and Asia. 65

_ Now taking the same figure as that illustrating Part II., and imagining a body of
weight JV, in motion at the point 4, due to its fall from a, and rolling to B, that is,
descending through the vertical height marked H.

Let u be the resistance opposed to sliding and rolling of the body down the plane.
If the body meets many small obstacles in its path, this will be analogous to a
frictional resistance.

lst. Owing to its initial velocity, the body will have at starting from 4, an
WAG WAVE
energy measured by 3 ——, but V?=29 Kseca.°. 4 =WKsec a.

2nd. The work done by gravity upon the body through the vertical distance H,
is measured by WH.
3rd. The work done against friction is « 7 cosa H cosec a= WH cot a.
Now when the body comes to rest rolling down the height H, its power of doing
work must have been absorbed, or is equivalent to the work done against frictional
resistances,

Therefore VKseca+ Wh=p WH cota
Whence H= XK see a
ecota —1
Taking the angles
10°, 20°, 30°, 45°, and 60°, where for the sake of example let u = 4
then H co :55; 2:8; ©; 0; @.

That is te say, bodies on planes with an inclination above 30°, where the resistance to
rolling was only half the weight, would roll on until they reached the base of the
plane, whatever its length might be, getting faster as they descended ; whereas two
similar bodies on planes only differing in their inclinations being respectively 20° and
10°, the body on the plane of 20° would roll more than fowr times as far down as the
one on the plane of 10°.

Taking another case, where 7 =7, and the planes remaining the same,

Jil ey Bil, ils Bo; eis Cd.

Now it is clearly seen that as ~» might be much greater than ?, the action is pro-
bably much more intensified than it is here shown. It is also easy to see that it we
take into account the probable mechanical action of water in detaching stones and
other possible agencies, the action would also be more intensified than is indicated by
the above numbers.

It is evident, however, that no mechanical theory can take into
account the infinite number of phenomena which really occur;
nevertheless these considerations will perhaps give an idea of some
important circumstances which affect the rates of degradation of
steep mountains.

After more than a week’s rest, I left Pekin on the 24th, my
destination being Tiensin. ‘This occupied two days. The country
travelled over was an open flat loamy plain, similar to that which I
crossed when entering Pekin. At Tiensin I found the river still -
closed by ice, and if I intended travelling to Shanghai by steamer,
I should have several weeks’ delay. This being the case, I deter-
mined to travel overland in mule carts, a journey which I was told
would occupy about twenty days. It was the 5th of February
before everything was prepared for the journey, and at 12 o’clock
on that day, in company with a Russian officer, Colonel Unterberger,
who also wished to reach Shanghai as quickly as possible, I started
off on a trip of new experiences.

For the first six days we rattled along over a continuation of the
Tiensin and Pekin plain. With the exception of a few canal banks,
mud walls of villages, and fences round fields, everything is
painfully flat. Every step one takes raises a cloud of dust,

DECADE II.—VOL, V.—NO. II, 5

66 Prof. Milne—Across Europe and Asia.

which, when the wind is blowing, becomes unbearable. At times
this was so thick that you appeared to be surrounded by a fog, and
on one occasion it was so bad that a midday halt was called, and we
sought refuge in an inn, where we remained until next morning.
The fine impalpable dust, which is raised in clouds at every puff
of wind, indicates the nature of the loam with which these plains
are covered, and also tells us something of its origin, which was
probably as a sediment from the flooding of some large river. The
fresh-water origin of these plain deposits has often been before
referred to, a view which is confirmed by shells I found in it above
the Nankan Pass, and afterwards in Shantung. These were Cyrena
and a Helix, and in the more recent river deposits, Glaucomya and
Anodon.

Mr. Pumpelly, in the paper to which I have before referred,
speaks at length about somewhat similar sediments to these which
he considers to have been deposited in a chain of connected lakes.
Unfortunately his explanation of the origin of these lakes is very
vague, what he says being that it is probably to be sought in the
dislocation forming the plateau wall to the north of them, the
descent of the land previous to that event having probably been
toward the Gobi, in which direction also the Yellow River flowed, if
it existed at that time. How far this lake theory may be applied to
districts covered with alluvium lying far back in the interior of
China, as in Ordos, the land lying in the northern bend of the
Hwang Ho, or to the deposits in Hupeh on the Yangtse, I am unable
to say; but certainly those deposits which I saw when crossing
the provinces of Chihli and Kiangsu would, from their position alone,
forbid such a supposition. As Mr. Pumpelly tells us, they appear
undoubtedly to represent a delta-plain. The river which formed
this plain is the Hwang Ho, which has been partly assisted by the
Yangtse. Looking at any ordinary atlas, it will be seen that the
Hwang Ho now discharges itself into the Gulf of Pechihli, on the
northern side of Shantung; whilst its old course is marked by dotted
lines, showing that formerly it discharged itself into the Yellow Sea,
nearly 500 miles farther to the south. This change took place
between 1859 and 1860, when a breach was made in its banks 30
or 40 miles south of Kai-fung-fu. This may have arisen from the
banks having been neglected, or it may have been done purposely to
prevent the advance of troops, it then being the time of the Taiping
rebellion. How easily this river could devastate a country, I readily
perceived on reaching its banks, which was on the 11th of February,
the same day that I saw the mountains. At this point, which was
near the city of Chi-ho-hsien, the breadth of the stream must have at
least been from 300 to 400 yards. It was apparently very low, and
at least 25 feet below water marks in banks on either side by which
it was bounded as if between two walls. These banks extend as
ridges across the surrounding flat country, and it was not until we
climbed to the top of them that we could see anything of the water,
which was rapidly flowing along as a muddy stream at the rate of about
200 feet per minute. This rate was calculated by walking down the

Prof. Milne—Across Europe and Asia. 67

banks, and keeping pace with blocks and pans of ice which were
being carried down towards the sea. At present, during flood-time,
the waters of this river must, I think, be above the level of the
surrounding country. In its old course its bed, which I subsequently
walked across, was above this level. In the course of years, by the
deposition of part of the sediment with which its waters are ever
densely charged, the bottom of the new course will be similarly
raised. As the bed is thus raised, the waters rise, and the inhabitants
have either to raise the banks or else suffer from inundation. The
case is analogous to portions of the River Po in Italy. Man
struggles against the vast accumulation of sediments by the waters
of these great rivers, but every now and then they break through
their bounds and show themselves victorious. Large numbers of
workmen are employed to maintain these banks, and should these
neglect their duty, or be withdrawn by a chief wishing to appro-
priate the funds entrusted to him for the carrying out of these
works, a calamity results, which, for the destruction of life and
property, is unparalleled. In times of war breaches have wilfully
been made in these banks, and conquests which were almost instan-
taneous have been effected.

In this way, by accident or intention, the Hwang Ho has often
devastated the surrounding country with floods, and made great
changes in its courses. Mr. Pumpelly gives ten maps illustrating
the different channels this river has had since the year 602 B.c.
These changes appear to have been as follows, the table showing the
number of mouths entering into the Gulf of Pechihli and the number
entering the Yellow Sea.

YELLow SEA. | Guur or PECHIHLI.
1. From the time of Yu down to 602 B.c. One Three
2. During the Chow Dynasty, 602 B.c. None One or perhaps two
3. Third century B.c. One Perhaps one
4. About 132 B.c. None One or perhaps two
5. About 11 B.c. None Two
6. From a.p. 70 to a.p. 1048. None Two
7. From a.p. 1048 to a.p. 1194. None Two
8. Under the Kin Dynasty. One Two
9. Under the Yuen (Mongol). One One
10. At present. None One

At each of these periods there is record of a great change having
taken place in the course of the river, the alterations not only as to
the sea into which it flowed, but also in the direction of its channel,
having been very great. When it flowed by one branch into the
Yellow Sea, and by one branch into the Gulf of Pechihli, its lower
course might be represented by the letter Y, between the forks of
which was situated the rocky province of Shantung, round the back
and along the sides of which these alluvial plains extend. The fact
that the Hwang Ho often changes its course, and in doing so floods
the country, and that but for the interference of human agency this
would be of more frequent and continuous occurrence, together
with the relation its branches hold to the province of Shantung, are

63 Prof. Milne—Across Europe and Asia.

circumstances which must not be overlooked when considering the
origin of the great plain of Hastern China.

The quantity of sediment brought down by this river must be,
from what I saw, very great. Barrow estimates it as being 2,000,000
cubic feet per hour. This quantity of material being continually
deposited near the mouth of the river, naturally tends to shallow
the ocean and to increase the present extent of the delta. As an
example of this increase, Mr. Pumpelly tells us that “in B.c. 220
the town of Putai is said to have been one li west of the sea-shore,
while in a.p. 1730 it was 140 li inland,” which is equivalent to a
yearly increase of about 100 feet.

Taking this with the facts already mentioned, we can readily carry
ourselves back to the time when the mouths of the Hwang Ho, and
with them the sea-coast, were much farther inland than they are at
present, and the province of Shantung was lying out at sea like a rocky
island. Since then there has been a gradual deposition of material
going on, and the coast-line has been encroaching on the sea. What
is more, I believe it probable that this action may have been
augmented by the operation of a slow elevation. The possibility of
an old sea-margin, although not advocated, is indicated by Mr.
Pumpelly as perchance existing, from the fact that the arms of the
Hwang Ho have not approached the western mountain border of
the plain. Taking this in conjunction with the evidence of recent
elevation existing in surrounding countries like Japan and Siberia,
that there has been such an elevation, although by no means proved,
is shown to be within the pale of probability.

After crossing the Hwang Ho, we ascended the slope towards
the Shantung hills, which we had seen before us. In doing so,
we passed through several defiles in the alluvium which flanked
their sides. This alluvium, instead of being a homogeneous mass
of consolidated silt, like that we had been crossing in the plains,
now contained pieces of limestone and fragments of other rock,
evidently derived from the hills upon which it lay. The same
processes of degradation had in times gone by, just as at the present
day, been occupied in moving the detached stones of the hills
towards a lower level. On reaching the region where silt was
being deposited, they were gradually covered up and buried, and
in this way no doubt the greater number of stones we saw in
the alluvium arrived in their present position. On the sides of
the hills before us, and ‘stretching up their valleys, we could
see terraces of ground which had been formed for purposes of
cultivation, reaching up to the very limits of the alluvium. As we
ourselves gradually ascended towards this limit, the loam grew
thinner, and assumed a slightly reddish tint. This colour I fancied
due to the strata of these parts having been deposited in shallow
water, where, by the action of the air and the sun’s warmth, oxide
of iron was more readily deposited than it would have been in
deeper water, not containing so much oxygen, or being so near its
source. I noticed a case of this sort actually in operation along
the gravelly shores of the river Tom in Central Siberia. On a

Prof. Miine—Across Europe and Asia. 69

smaller scale it may be seen around the edges of ponds-or even
puddles where the water is at all chalybeate—an analogous
phenomenon being produced in the chemical laboratory when solu-
tions containing iron are being evaporated.

After passing the village of Kaisa, we were fairly amongst the
hills, which were grey and rugged, half their surface being covered
with grass, and the other half bare rock. Judging by the stones
beneath our feet, and from the rocks which here and there cropped
up, these hills apparently consist of a bluish-black hard limestone,
which, from its resemblance to that I passed before reaching the
Coal-fields lying to the North of Pekin, and from the fact that Coal
is likewise found in this neighbourhood, I should be inclined to
think was also of Carboniferous or else of Devonian age. The strata,
which in many places are distinctly visible, have a slight dip of about
1° towards the north.

In many places amongst these mountains we passed through narrow
defiles in the alluvium. These seem to have been cut down through
the alluvium which fills the bed of these valleys chiefly by the agency
of traffic. They could be seen in all stages from mere rut marks to
deep cuttings flanked with perpendicular walls 40 and 60 feet in
height. When in these latter, looking up at the loose material above
you, charged with stones ranging from small pebbles to huge
boulders, you could not but speculate on the risk incurred by passing
travellers. Some of these defiles were so narrow that we had to wait
until the line of wheelbarrows, carts, and people, which are as thick
upon these country roads as they are upon a market-day in a country
town at home, going in a direction opposite to that in which we
were travelling, had passed out before there was room for us to
enter. In the mountain wadies of North-western Arabia I have
noticed the formation of cliffs of earth which are very similar to
these in China. The growth of these truly perpendicular walls
in Arabia appears to result from the undermining action of the little
water which sometimes trickles down these wadies, together with
that produced by a sand-drift which is ever working along their
lower portions. When this has gone on for a certain distance, the
superincumbent material, having little or no lateral attachment to the
contiguous mass, falls down. There being nothing in the material to
produce an unequal disintegration, should it commence at any one
point, it is at once carried very rapidly over the surface of the plain
in which it commenced, the materials being so loosely placed together
that they are mutually dependent. Similar causes no doubt aid in
the formation of the Chinese gulleys. Those which run back towards
the mountains as tributaries to these main arteries of traffic have
no doubt also been hollowed out by the action of water, which, com-
mencing at the bottom of the valley, worked its way backwards up
towards the hills, much in the same way that a waterfall acts upon
the face of rock over which it drops.

Next morning at 8 a.m. (Saturday 12th) we reached a point where
the limestone ended and gave place to granite. With this change,
both hills and roads were rougher. About 12 o’clock we crossed

70 Prof. Milne—Across Europe and Asia.

the water-parting, and apparently the axial line of the granitic
nucleus. In the afternoon we passed Tainan, a large and compact
town, beautifully situated beneath a high rugged clump of granitic
mountains. Beyond this town we emerged upon an open plain,
and we were not a little pleased to be relieved for a time from the
rough jolting we had been undergoing in our springless carts over
bouldery roads.

The occurrence of granitic rocks in this portion of Shantung,
coupled with what has been observed further to the north-east, as, for
instance, near Cheefoo, would indicate that this province has altogether
an axis of granite rather than one partly of Devonian Limestone, as
indicated upon Mr. Pumpelly’s ‘‘ Hypothetical Map of the Structure
of China.”? Although we now travelled upon a plain, high moun-
tains yet remained both upon our right and left. That night we
crossed the river Van Ho. It was about 100 yards broad, and deep
enough to reach the axle-trees of our waggons.

Next morning, Feb. 13th, we bent our course towards the east,
and turned up a slope on to a low part of the hills, which upon the
previous day had been upon our right. These were granitic, and
round and undulating in outline, reminding me in contour of some
of the mining districts in the vicinity of Land’s End in Cornwall.
From the materials used in building houses and walls in this
district, I think that, in addition to the granite, limestone must also
occur. The ground around was, however, covered with quartz and
degraded felspar, the result of the decomposing granite. During
the afternoon our course was 8§.8.H. along a plain six or eight miles
broad, bordered right and left by hills, which were partly limestone
and partly granitic. The limestone hills were seen first upon our
left, but afterwards upon both right and left. These dipped at about
15° N. About 5 p.m. our road led us over a ridge of earthy red
beds, which dipped at 10° N.W. Disseminated through them were
nodules of white calcite.

All next morning (14th Feb.) we travelled over limestone projec-
tions, and boulders produced by weathering, which made our
road so uneven, that we could not remain in our carts. A large
town called Moiinshan, which we passed, had walls built out of
this grey limestone. I also noticed blocks of conglomerate, and a

Granite. Limestone. Alluvium. Limst. Alluvium. Granite.

7

ic

Diagram.—Section across the valley near Dowdjoa, Shantung. The mountains
are granite, the floor of the valley is limestone, with a superficial covering of alluvium.

1 See Contributions to Knowledge, No. 202, of the Smithsonian Institute.

Prof. Milne—Across Europe and Asia. 71

reddish sandstone. On our left we still had hills consisting of a
yellowish grey limestone dipping S.E. at 10°. Farther on, the lime-
stone became blackish, then shaly, and afterwards pinkish. This
limestone is not so hard and cherty as that which I saw when enter-
ing the Shantung mountains. About midday, near Dowdjoa, the
granite again commenced, both upon our right and left. On this
the limestone appears to rest, and on that again the alluvium, as
illustrated in the accompanying section taken from N.E. to 8.W.
across the valley down which we were journeying.

During this part of our course we crossed the sandy beds of many
small rivulets, which either found their way through a gap in the
mountains upon our right, or else joined a stream running parallel
with us.

Next day, Feb. 15th, the country appeared rapidly to be growing
flatter. After passing Pinghaho, within the distance of a mile, we
crossed the successive outcroppings of the following four beds :—

1. A volcanic rock forming a rounded knoll.

2. A Red Quartzose Sandstone.

3. Beds of Black and Yellow Shales, which were very thin, fissile,
argillaceous and slightly calcareous.

4. Overlying all the above, a highly Calcareous Sandstone, which, being
harder than number 2 or 8, stood above them as a small ridge.

These rocks, which strike N.E. and §.W. and dip 10° E., from their
lithological resemblance to the rocks of the Coal-measures, I take as
belonging to that formation, as indicated in Mr. Pumpelly’s map, to
which I have before referred. About half an hour after passing
these beds, I saw the outcrop of a porphyry containing large crystals
of felspar, which was immediately followed by a granitic country
traversed by quartz veins stained with iron oxide.

At 2 o’clock in the afternoon we forded a large stream, 50 yards
broad, running towards the south-east, and immediately entered the
large town of Hjow.

At 6 o’clock in the evening we forded a rapid river running to
the right, called the Yee Kai, and entered the town of Yee Kai San,
where we remained for the night.

Next day we were fairly out upon the open alluvium plains, and
the only hills we could see were some very low ones, away upon
the western horizon. On Thursday, the 17th February, we crossed
the gravelly bed of an old river which must have been 200 yards in
breadth, and, from the direction in which the sharp edges of the
piers of an old bridge were yet standing, must have run to the left.
On Friday the 18th, we travelled a short distance along the embank-
ment of a canal about 50 yards broad and running east. About
midday we walked through the embankments and across the old
bed of the Hwang Ho, which is now under cultivation, immediately
afterwards entering the town of Tsingkianpu, where we left our
carts and engaged a boat upon the Grand Canal. The stream being
with us, and the wind favourable, we travelled rapidly. On Mon-
day we passed a breach in the right bank, and obtained a view of
the Lake Koieokho. This lake is about 15 feet deep, and is con-
nected with the canal, which, at this point, is itself only 24 to 38 feet
in depth.

72 Prof. Milne—Across Europe and Asia.

On Tuesday, the 22nd February, we reached Chingkian on the
Yangtse, where we were fortunate in meeting a steamer, which
next morning landed us in Shanghai, after a quick trip of 19 days
since leaving Tiensin ; six months and three weeks since leaving
England. This latter section of my journey through half the
length of China, although not so trying as the trip I had just
experienced in Mongolia, was both tedious and disagreeable.
Everywhere one was followed by crowds of people, who called one
a “foreign devil.” Sometimes we were refused admittance at the
inns, and had, in consequence, difficulties in finding lodgings. We
had to travel from before sunrise, often 4 a.m. until after sunset, in
a springless vehicle, drawn generally at a trot over rough roads.
These facts alone, without the enumeration of others, will at once
be recognized as being sufficient to render observation almost an
impossibility.

The first part of this journey from Kalgan to Pekin has been
described by Mr. Pumpelly, who made many excursions in the
neighbourhood of these towns, and my scattered notes are only con-
firmatory of what he has already written.

On the remainder of my journey between Pekin, Tiensin, and
Shanghai, my observations, although fragmentary, may be useful as
giving a general idea of the structure of this portion of China, and
adding something to its geological cartography.

The provinces traversed were Chihli, Shantung, and Kiangsu.
Shantung, which runs from N.E. to S.W., appears to have a central
axis of granite. Flanking this, upon the 8.E., there are limestones,
shales, and sandstones, and upon the N.W. limestones. A portion
of these latter may be Devonian, but the remainder, together with
those upon the 8.E., are probably Carboniferous. These formations
make Shantung a mountainous province, and give a character to its
natural products and to the industries of its people.

Lying round this, from the shores of the Pechihli Gulf on the
north, extending as a semicircle down to the Yellow Sea, are plains
of alluvium representing a delta formation of the Hwang Ho.

Conclusion.—After arriving at Shanghai, I took a ship to Japan,
where I arrived on the 8th of March, 1877, after seven months and
seven days travel, which brought me fairly to the limit of the subject
embraced under the title of this paper, “Across Europe and Asia.”

The land journey between St. Petersburg and Shanghai was more
than 6000 miles, 4000 miles being through Russia and Siberia, 800
miles through Mongolia, and about 1000 miles through China. Con-
sidering the distance travelled, and the time occupied upon the
journey, it is unsatisfactory to look at the little information bearing
on geology which I was enabled to collect. The chief cause of this
was from the fact that it was imperative that I should always be
moving, not only during the day, but also very often during the
night. Not knowing the language of the country in which I
travelled, precluded me from inquiry. Again, many districts, like
the Siberian Steppes, presented a monotonous sameness throughout
their area, whilst the least known, and, I believe, the most interesting,

Dr. James Geikie—Preservation of Deposits under ‘ Till” 73

section of my journey in Eastern Siberia and across Mongolia, not
only was everything buried in snow, but the cold was so intense
that I could do little more than attend to personal requirements. In
China, the chief detriment to the making of observations was the
rapidity of travel, which prevented any deviation from the track,
coupled with a rude and ignorant inquisitiveness displayed by the
inhabitants, from whom there was no escape.

These circumstances will, I think, sufficiently explain the meagre-
ness of my notes, and at the same time the origin of any inaccuracies
should they perchance be found to have unobservedly or unwittingly
crept in. Here and there upon my journey, especially in Siberia, I
found friends who endeavoured to exchange ideas ; but unfortunately,
with but few exceptions, I found my ignorance of Russian usually
prevented my obtaining a tithe of what I might otherwise have
learnt. Whilst subsequently writing out these notes, being without
the means of reference may in all probability have caused me to
put forth arguments either for or against which there may be much
evidence yet remaining to be adduced. In several instances my
arguments have been antagonistic to the existence of polar ice-caps,
but this has only been in regard to the production of certain phe-
nomena. All that I endeavoured to show is, if these mighty engines
existed, their traces must in many cases have been subsequently
obliterated, and what is more, many of the so-called glaciated
regions of the world I believe to have been produced by coast-ice
acting on a rising: area.

When speaking of the origin of the Siberian Steppes, as in the
case of the glaciated rocks I saw in Finland, I have endeavoured to
explain their origin by existing agencies rather than referring to
those the origin and action of which were more debatable.

What I said of the earthquakes of Hastern Siberia I gathered in
part from an epitome which is given of them by Messrs. Orlof and
Shtuikin in the Siberian Calendar for 1875.

The remainder of my information was gathered from personal
observation or from persons more or less conversant with the sub-
jects on which I have written, to all of whom I think I have before
referred, and whom I now take the opportunity of kindly thanking.

It therefore only remains for me to put my fragmentary jottings
forth to be sifted, arranged, and taken for their worth. In some
cases I may have been mistaken in my observations. or have over-
estimated their worth; but where this is so, feeling my fallibility, I
hold myself open to conviction.

1V.—On tur Preservation or Deposits or INconERENT MATERIALS
UNDER TiLt orn BovuLDER-CLAY.
By James Gerxin, LL.D., F.R.S.
HOSE who maintain that Till or Boulder-clay has not only
originated but accumulated underneath glacier-ice may some-
times have felt puzzled to account for the preservation of beds of
more or less incoherent materials below a deposit which they have
sO many cogent reasons for believing to be a true moraine profonde.

74 Dr. James Geikie—Preservation of Deposits under * Till.’

How could such loose stuff as gravel, sand, and silt withstand the
grinding action of a superincumbent ice-sheet? And how, if these
deposits have been thus traversed by ice, can we reconcile that with
our belief in the excavating power of an ice-sheet? ‘This, indeed, is
the principal objection urged by Mr. 8. V. Wood and others who
deny altogether that Till or Boulder-clay has been amassed below
ice. They deem it quite impossible that an ice-sheet could pass over
such beds as I have referred to without obliterating them; and having
assumed so much (for, of course, it is solely upon 1 their preconceived
ideas as to how a great ice-sheet would behave, that their objection
is based), they find no difficulty in concluding that Till could not
have been accumulated under ice, and that the occurrence of Till
resting upon beds of gravel, sand, and clay, is no proof whatever
of the former passage of an ice-sheet. In this short paper, however,
I do not mean to enter upon the question of the mode of formation
of Till. Quite enough ink has already been shed upon the subject.
Every day supplies me with fresh evidence in favour of the view
which I support—namely, that Till has not only been formed but
also accumulated under an ice-sheet; and I am not aware of any
phenomena which this theory of the origin of Till fails to explain,
although very many facts are known to me which are quite irrecon-
cilable with any other view. My object. at present, however, is not
to point out the inadequacy of other theories and hypotheses—in
doing which there would necessarily be much repetition of many
unanswered arguments—but simply to show that a strong and well-
grounded belief in the erosive power of ice is quite consistent with
an equally firm conviction that in many cases thick masses of ice
have crept over beds of gravel, sand, silt, clay, and peat. The one
persuasion is no more contradictory to the other, than a serene confi-
dence in the denuding powers of running water is opposed to the
belief that the same water also deposits and accumulates detritus
while it flows. One may surely hold that a certain deep ravine or
glen, in the upper part of a river-valley, has been excavated in the
course of ages by the stream one sees at the bottom, and at the same
time assert, without the fear of being considered self-contradictory,
that the broad alluvia (overlying, it may be, incoherent marine
strata), in the lower and more open reaches of the valley, have been
deposited by the very same river that dug out the deep ravine above.
What I and others, who hold with me, maintain is simply this: first,
that, in regions where the erosive action of the ice-sheet was great,
little or no Till was allowed to gather, and rock-basins were scooped
out, when the nature of the ground was favourable to that end ; and
secondly, that, in places where the grinding-power exerted was less,
thick Till frequently accumulated, and subglacial and interglacial
beds were often preserved.
Our ice-sheet flowed, we cannot doubt, with a differential motion :
it must have moved faster in some places than in others. In steep
valleys and over a hilly country its course would often be compara-
tively rapid, but very irregular—lagging here, flowing quickly there
—while in wide, open valleys that sloped gently to the sea, such for

Dr. James Geikie—Preservation of Deposits under ‘ Till” 79

example as those of the Forth and the Tweed, the whole body of
the ice would flow with a slower and more equable motion. As the
ice-sheet approached its termination, more especially if that terminus
chanced to be upon a broad and comparatively flat region, like East
Anglia, the erosive power of the ice would become weaker and
weaker for two reasons: first, because of its gradual attenuation, and
secondly, because of its constantly diminishing motion. These, in a
few words, are the varying effects which one might @ priori infer
would be most likely to accompany the action of a great ice-sheet.
And an examination of the glacial phenomena of this and other
countries shows that the actual results are just as we might have
anticipated, had it been previously revealed to us that a large part of
our hemisphere was, at a comparatively recent date, almost entirely
smothered in ice. In places where, from the nature of the ground,
we should look for traces of great glacial erosion, we find rock-
basins; in broken hilly tracts, where the ice-flow must have been
comparatively rapid but irregular, and the glaciation severe, we meet
with roches moutonnées in abundance, but with very little Till; in
the open lowlands and in the broad valleys where the ice-sheet
would advance with diminished but more equable motion, we come
upon widespread and often deep glacial deposits, and now and again
with interglacial beds ; while over regions where the gradually de-
creasing ice-sheet crawled slowly to its termination, we discover
considerable accumulations of Till, often resting upon apparently
undisturbed beds of gravel, sand, and clay.

The distribution of interglacial deposits, therefore, is really in itself
a proof that they have been overridden by ice. When they occur in
highly glaciated regions, it is only as mere patches, which, occupying
sheltered places, have been preserved from utter destruction. In
the opener low grounds they are found in greater force, although
in such places they almost invariably afford more or less strong
evidence of having been subjected to much erosion and crumpling.
But the further we recede from the principal centres of glaciation,
and the nearer we approach the extreme limits reached by the
ice-sheets, the more extensive and the less disturbed do interglacial
deposits become. In a word, they occur in best preservation where
the erosive power of the ice was weakest; they are entirely wanting
where we have every reason to believe that the grinding force was
strongest.

Tf we look at the interglacial beds themselves with any attention,
it is very rarely indeed that we shall not find proof of their having
been subjected to more or less crushing and erosion. The overlying
Till cuts into them again and again—they are often caught up and
involved with the Till—and crumpling and contortion are frequently
conspicuous. No one who has paid much attention to glacial matters
will doubt that all this powerful erosion and confusion are due to
the passage of ice over the beds. It may be taken as proved,
therefore, that an ice-sheet does under certain conditions ride over
incoherent deposits of gravel, sand, silt, clay, and peat, without
entirely obliterating them. But all interglacial beds, even in highly-

76 Dr. James Geikie—Preservation of Deposits under ‘ Till.’

glaciated Scotland, are not equally crumpled and contorted. Oc-
casionally the layers of sand and laminated clay lie quite horizontal,
-even when the Till cuts down, as it were, to the depth of 20 feet
and more into the stratified deposits. We have, therefore, further
proof that ice may roll its bottom-moraine over incoherent deposits
without disturbing the horizontality of their bedding, although at
the same time these same deposits may here and there be abruptly
cut out and truncated.

Tf such has taken place in the valleys of a well-glaciated country
like Scotland, it surely cannot be unreasonable to infer that in a less
ice-worn country, in a region where the ice was not so thick, and
where its motion was slower, interglacial beds should be much
better preserved. If the ice has spared, in hilly Scotland, inter-
glacial deposits that range in thickness from a foot or two up to
twenty yards and more, where is the improbability of its having
overridden much thicker and more continuous deposits in those
low-lying parts of England where it approached its termination ?

And here I may remind geologists of one among many equally
suggestive facts, connected with the distribution of interglacial beds
in Scotland, that while we have indubitable evidence of a sub-
mergence of the land, during the last interglacial period, to an
extent of upwards of 500 feet, the marine deposits of that date have
yet been all but entirely swept away from the higher levels and
more exposed parts of the country—there being only one place
where they are met with so high up as 500 feet. It is not until we
get down to the low country—to the wide open valleys, and to the
borders of some of the great friths (which are merely submerged
valleys)—that we find the relics of the marine stage of the last
interglacial period coming on in force. An excellent example of
this peculiar distribution of interglacial marine deposits came before
me recently in the Outer Hebrides. Interglacial beds are met with
in two places in the Long Island, namely, at Ness and in the Hye
Peninsula. The highest point attained by these deposits is about
200 feet above the sea. ‘They rest upon an eroded surface of Till,
and are themselves overlaid by a second or upper Till, underneath
which they show a most irregular surface, as a rule, being cut into
by the Till and crumpled, contorted, and confused. In other parts
of the same cliff-sections, however, they show little or no dis-
turbance at all, but the Till rests upon them apparently quite
conformably. In the Eye Peninsula they occur as a mere local
patch, which exhibits all the appearance of having been scooped and
ploughed ont—the clay being abruptly truncated, and overlaid by
red Till. When these interglacial beds were accumulated, all the
low grounds of Lewis, up to a height of 200 feet at least, must
have been submerged—and this submergence could hardly have
been local and confined to Lewis, but extended in all probability to
the whole Outer Hebrides. Where, then, we may well ask, are the
marine deposits which must at one time have cloaked these low
grounds—where are the clay-beds and sandy deposits and beach
accumulations which must have been laid down contemporaneously

Dr. James Geikie—Preservation of Deposits under ‘ Till” 77

with the interglacial beds at Ness and Garrabost? The low grounds
in question are sprinkled solely with Till, and dotted with morainic
rubbish and erratics. Instead of marine deposits, we see only the
marks of a recent and severe glaciation. Every vestige of the
last interglacial occupation by the sea (with the two exceptions
mentioned) has been swept away by the ice-sheet, whose bottom-
moraine was rolled over the shell-beds at Ness and Garrabost.
And the principal mass of these deposits occurs in the very position
where, as I shall have occasion to point out more particularly in
another place, the ice-sheet must necessarily have exerted less grind-
ing power.

I have drawn attention elsewhere to certain remarkable facts con-
nected with the distribution of interglacial beds in North America,
and have pointed out that the researches of our fellow-labourers
in the States and Canada have proved that American interglacial
deposits occur in the same peculiar manner as our own :—they are
absent or very rarely met with in the regions north of the great
lakes, and they increase in importance as they are followed south.
Quite recently Mr. G. Jennings Hinde, of Toronto, has described
some very interesting and important sections, which are exposed
upon the shores of Lake Ontario.t These sections show no fewer
than three separate beds of Till with intervening stratified deposits,
the lower one of which has yielded many plant-remains and fresh-
water organisms. The section extends continuously along the shores
of the Lake for a distance of nine miles and a half, and the fossil-
iferous interglacial beds attain a thickness of 140 feet. Occasionally
they are violently contorted and confused, and in one place the
overlying Till cuts down into them to a depth of more than 100
feet—the breach occupied by the Till beitig about 450 yards in
breadth. Yet throughout the greater part of the section this over-
lying Till rests apparently quite conformably upon the stratified de-
posits, which then show perfectly horizontal and undisturbed bedding.
Here, then, we have a case where one and the same ice-sheet has
ploughed out incoherent strata, driving a deep and broad trench
through them, although here and there it has allowed them to escape
with only severe crumpling, contortion, and confusion, while in yet
other places it seems to have rolled its bottom-moraine quietly over
their surface in such a way as to leave the beds apparently un-
denuded and undisturbed.

The same geologist writes me that “up to the present time these
interglacial clays, etc., appear to occur only in the lake-depressions
and other localities at low levels. I cannot find them in the more
elevated districts, and supposing a fresh glacier now to creep over
this country, it would sweep before and beneath it the Till on the
uplands, and cover over the stratified clays in the present lakes with
this material; and there would thus be a repetition of the same
arrangement of stratified beds and overlying Till as is now seen in
the present cliffs facing the lake.” He thinks that the earliest
ice-sheet had more grinding power than the ice-sheets of later cold

1 Canadian Journal, April, 1877.

78 Dr. James Geikie—Preservation of Deposits under ‘ Till.’

periods; but the Till that overlies the fossiliferous interglacial beds,
indicates nevertheless, the former presence of a very considerable
ice-sheet, for the beds which it has spared are the mere fragments
of what must have been widely extended deposits covering a broad
region, from which they have since been entirely removed.

Mr. Hinde tells me also that he has just discovered plant-remains
in a similar position near Cleveland, Ohio. The deposits at this
place are described by Dr. Newberry as his “pebbly Erie clay.”
They consist, my correspondent says, first, of Till at the lake-level ;
secondly, of about 48 feet of sand and loam, containing a layer of
plants; and thirdly, of good unstratified Till full of striated stones,
—six feet thick. The interesting point about this section is the
occurrence of plant-remains in beds that belong to Dr. Newberry’s
“laminated clay series”—a series which that able geologist has
described as unfossiliferous, and never overlaid by Till.

I might easily refer to many examples of similar phenomena in
the glaciated districts of Northern Europe, to show that the distri-
bution of interglacial beds is the same there as in our own country
and North America. But I need not enter further into details at
present. It is enough for my immediate purpose to have again
pointed out that, in considering the origin of glacial and interglacial
deposits, it is needful that we pay more attention to the distribution
of these beds than we have hitherto done. This is the direction in
which, as it seems to me, we must look for the key to the whole
mystery ; indeed, I do not see how otherwise we are to arrive at any
reasonable explanation of the phenomena. At the first blush it may
appear hard to believe that a great mass of solid ice could ever pass
over the surface of incoherent deposits of clay and sand. But the
appearances presented -by these deposits tell their own tale, and
teach us, as we have been taught before, that our preconceived
notions of what Nature’s forces can and cannot do are often enough
wide of the mark.'

It is needless to refer one to the petty glaciers of the Alps and
Norway to prove that glacier-ice cannot both erode its bed and
accumulate débris upon that bed at one and the same time. A
mountain-valley glacier is one thing—a glacier extending far into
the low grounds beyond the mountains, and, it may be, coalescing
with similar extensive ice-flows, is another and very different thing.
No considerable deposit could possibly gather below alpine glaciers
like those of Switzerland and Norway; but underneath glaciers of
the kind that invaded the low grounds of Piedmont and Lombardy
we know that thick deposits of tough Boulder-clay, crammed with
scratched stones, did accumulate ; and not only so, but that these
glaciers flowed over incoherent deposits of sand and clay containing
marine shells of late Tertiary age, without entirely obliterating them.

1 It may reasonably be doubted whether interglacial deposits were always so very
loose and incoherent at the time they were overridden by ice. My brother has
suggested that when the ice-sheet advanced over a land-surface, the loose superficial
deposits might be frozen so hard as to be capable of resisting a very considerable
degree of glacial erosion.

J. A. Birds—Geology of the Channel Islands. 79

The deposits referred to occur now as little patches within the area
bounded by the great terminal moraines.

As physicists themselves are not yet quite agreed upon the
subject of glacier-motion, it is not incumbent upon the geologist to
explain the precise mode in which a thick mass of ice can creep
over the surface of incoherent beds without entirely demolishing
them. It is enough for him to show how the remarkable distri-
bution of the interglacial beds, and the various phenomena presented
by these deposits, indicates that ice has overflowed them. It is
useless, therefore, to tell him that the thing is impossible. The
statement has been made more than once that an ice-sheet several
thousand feet thick is a physical impossibility, but unfortunately for
this dictum the geological facts have demonstrated that such massive
ice-sheets have really existed, and there appears to be one even now
covering up the Antarctic Continent. We used also to be told, not
so many years ago, that the abysses of ocean must be void of life
for various reasons, amongst which one was that the pressure of the
water would be too great for any living thing to endure. Yet many
delicate organisms have been dredged up from depths at which the
pressure must certainly be no trifle. Now there seems to be just as
little difficulty in believing that these organisms existed in a perfect
state at the bottom of the ocean, as that shells imbedded in clay
would remain unbroken underneath the pressure of a superincum-
bent ice-sheet of equal or greater weight. If the ice were in motion,
the clay with its included shells might be ploughed out bodily, or
be merely crumpled and contorted ; or it might be ridden over with
little or no disturbance ; or, on the other hand, it might become in-
volved with subglacial débris, and be kneaded up and rolled
forward—the shells in this case being broken, crushed, and striated,
just as we find that the shells in certain areas of Till have been.
The fate of the fossiliferous beds would, in short, be determined by
the rate of flow and degree of pressure exerted by the superincum-
bent quasi-viscous body—the motion of which would be largely
controlled by the physical features of the ground across which it
crept.

V.—GEOLOGY OF THE CHANNEL ISLANDS.
By J. A. Brirps, B.A.
Part I.—The Older Rocks.

N the most extended view, the Channel Islands may be regarded

_ as fragments and relics of the Hastern or European coast of the
Atlantic, reckoning from the North Cape to Cape St. Vincent, and
including the Western shores of Scotland and Ireland, and the pro-
montories of Pembrokeshire and Cornwall. They are excellent
illustrations, says Professor Ansted, “of those spurs and tongues of
porphyritic rock, of which almost all the promontories of the
Atlantic coast of Europe consist.”' Very small and insignificant
specks indeed they seem in such a length of coast, stretching from

1 The Channel Islands, by Ansted and Latham, 1862, p. 247.

80 J. A. Birds—Geology of the Channel Islands.

lat. 37° to 72°, or upwards of 2000 miles; but there is a charm in
such wide horizons, and it is a very allowable indulgence so to
connect the little with the great, and to consider the position of such
little specks in relation to the geography of Europe; one might
almost as well say, of the world at large. Having refreshed our-
selves, however, with such a glance at their widest geographical
relations, we must be content to confine our view within a very
much narrower compass, and to consider these islands simply as
relics of a tract, which once formed part of what is now Normandy
and Brittany ; just as the Scilly Isles and Lundy Isle are relics of
an area which once was connected with Cornwall and Devonshire—
the original and actual basis indeed of Arthur’s legendary kingdom
of Lyonnesse. This itself is no narrow view; but even if it were,
still we are not under any necessity—as in geology one never is—of
losing a great horizon and burying ourselves in a mass of details;
the only difference is that we must change our point of view, and
regard the area under consideration in the aspect, not of space, but
of time. Viewed in this way the series of rocks become so many
visible and tangible links, or landmarks rather—the chain being so
broken—leading the mind back into an almost infinite past.

It is not my purpose, of course, in this paper, to attempt any-
thing like a complete account, or even a resumé, of the geology
of these isles; that may be fully gathered from such articles as Dr.
MacCulloch’s, and others in the Transactions, Proceedings, and
Quarterly Journal of the Geological Society ; from Duncan’s “ His-
tory of Guernsey”; and, above all, from Prof. Ansted and Dr.
Latham’s work on the “Channel Islands.” All that I desire to do
is, to ask one or two questions about points which seem to me of
chief interest and importance, to bring together information from
the above works and elsewhere upon these points, and to add to
this the result of my own observation during the latter part of last

ear. ,

: The first question is as to the age of the granites, or rather
syenites, ‘granitals,’ schists, porphyries, sandstones, etc., of which
the islands consist.

Besides Prof. Ansted’s conjectures that the grits and sandstones
of Alderney are probably of Permian or Triassic age,' and the older
conglomerate of Jersey of the age of the Cherbourg grits’ (Bunter or
Lower Trias), I am not aware of any observations having been
published as to the date of the rocks.

Looking at a geological map of the north of France, or of
Normandy and Brittany, with which the islands stand in closest
connexion, one would conjecture @ priori that the sedimentary rocks
at least were either Silurian or Devonian, more especially when we
observe what is probably a continuation of these rocks across the
Channel in Devonshire and Cornwall.* The only positive evidence
in favour of such a supposition, that I have seen, is a small patch or

1 The Channel Islands, p. 269. 2 Ibid, p. 274.
3 See an article by the late Mr. Salter on “The Pebble Bed at Buddleigh

Salterton,’ Grou. Mac. 1864, Vol. I. p. 4, etc.

J. A. Birds—Geology of the Channel Islands. 81

rather one or two bands of schistose strata which make their appear-
ance in Rocquaine Bay, Guernsey ; and, again, the schists or shales of
Jersey.

In the former case the rocks are of a bluish-grey colour, weather-
ing brown, and have at first sight a general Silurian or Devonian
aspect. They are referred to by Prof. Ansted in a note concerning
the absence of any deposits in Guernsey more recent than the fun-
damental syenites and gneiss: ‘‘ A small patch of clayslate,” he says,
“in Rocquaine Bay is hardly an exception.”

This so-called patch (where I examined it) consists of two or
three bands of slate, which are imbedded in the midst of a felspathic
syenite, and dip at a very high angle to the east. I traced them
for about fifty or sixty yards on the land side of the fort called
Rocquaine Castle till they became lost under the sea. Probably, at
low water, they may be found in other parts of the bay. The cavities
left by decomposed felspar have often a very deceptive resemblance
to casts of Brachiopoda, and to encrinital remains; but I searched in
vain for any trace of fossils. Possibly these may yet be discovered.
Should this not be the case, the schists will not, of course, yield
any evidence of their age, or of that of the felspathic and horn-
blendic rocks amid which they lie. In a mineralogical point of
view, however, they would still be interesting, as showing a stage
in the progress of metamorphism, viz. a passage from sedimentary
schists into a greenish-grey porphyritic rock containing crystals of
felspar and calcite (?).

Alderney, according to Ansted,' besides the portion of sandstone
above referred to, consists entirely of syenite, with the exception of
a single boss of hornblendic porphyry, upon which Fort Touraille is
erected. Ortach and the Casquets, although few, if any, geologists
have landed to examine them, are believed to consist of similar
syenite or porphyry with cappings of the same sandstone as
Alderney. It is said that the syenite enters and pierces the sandstone
in the Casquets—a very important point—but one which requires
confirmation.

Of Guernsey I can speak from personal observation. It is di-
visible geologically into two or three very unequal portions by a
line drawn N.W. from some quarries just above St. John’s Church,
in the town of St. Peter, to some other quarries below Capelles
School; and thence again S.W. to a quarry on the right or north
side of the Cobo Road, close to Cobo Bay. About three-quarters, or
rather four-fifths, of the island south of this line consists of a very
felspathic syenite and gneiss, and the remaining quarter or fifth of a
hornblendic ‘ granital’—a compound of quartz and hornblende. A
third division consists of a syenite often charged with specks and
flakes of mica. This micaceous syenite may be traced along the
coast from near the centre of Cobo Bay and Grandes Rocques almost
to Fort Doyle, at the north-eastern extremity of the island. In
the centre of Grand Havre, however, and on Mont Cuet—between
Grand Havre and Lancresse Bay—and perhaps at some other points

1 The Channel Islands, p. 268.
DECADE II.—VOL. V.—NO, Il. 6

82 J. A. Birds—Geology of the Channel Islands.

along the shore, the syenite is interrupted by veins of the horn-
blendic granital. It does not extend far inland, but is soon replaced
by the mass of hornblendic granital constituting the north of the
isle.

Of the felspathic portion of Guernsey I have nothing to remark,
more than that it furnishes magnificent crystals of felspar, especially
in Moulin Huet and Petit Bot Bays, surpassing in size and brilliancy
of colour any in the porphyritic granites of Cornwall, or Shap Fell,
Cumberland. The cliffs are frequently intersected by veins of
greenstone and felstone running both parallel with, and at right
angles to the apparent bedding or jointing of the syenite. The
hornblendic portion of the island also occasionally (e.g. at St.
Sampson’s) affords splendid crystals of black hornblende, finer
indeed than any I have ever seen in England or Scotland. The
principal veins in this portion are of felstone, serpentine steatite,
and epidote, of which last I found some rather pretty crystals im-
bedded in quartz. Chlorite frequently occurs in the form of coatings
and stains.

The principal axis of elevation of the whole area of the islands is
said by Prof. Ansted to run W.N.W. and E.S.E., and is regarded by
him as a continuation of the great east and west elevations affecting
the Continent of Europe, which are best illustrated in the range of
the Alps and Pyrenees."

The little island of Sark consists of syenite, with similar veins, as
in Guernsey, of greenstone, felstone, serpentine, steatite, etc., and of
hornblendic rocks, along with porphyry and trap. The hornblende
is said to occupy the extreme ends, and to form a belt across the centre
of the island, while the felspathic syenite fills up the intervals. The
axis of elevation here, and also in the little islands of Herm and
Jethou, between Sark and Guernsey, is nearly at right angles to
the axis of the latter, or N.N.E. and §.S8.W., and corresponds, says
Ansted, rather with recent elevations and depressions than with the
original upheaval.’

I was not fortunate enough to find any, or at least good specimens
of the minerals with which Sark is said to abound. The old mine-
heaps appear to have been thoroughly ransacked, and the shores are
inaccessible except at a few points; only on the beach at Epercherie
—the original landing-place—I picked up specimens of fine black
hornblendic porphyry containing well-defined crystals of felspar,
and afew pebbles of agate and jasper, generally much decayed, as
well as some of serpentine, and a green mineral, which I take to be
actinolite. The vein of kaolin, stained purple and pink, crossing
the north side of the Coupée, is very conspicuous. Dr. MacCulloch,
in his map of the island, indicates three other veins,—1, of quartz,
chalcedony, jasper, and agate; 2, talcose schist with steatite; 3,
chlorite with pyrites; crossing the Coupée parallel with the kaolin.
None of these are visible from above, one side being covered with
detritus, and the other plunging down perpendicularly into the sea.

1 Ansted and Latham’s Channel Islands, pp. 256, 260.
2 Tbid, p. 263.

J. A, Birds—Geology of the Channel Islands. 83

The shores of Sark are generally more or less inaccessible; and the
only way to explore the island properly would be from a boat.

Of Jersey Prof. Ansted has given the following section, which I
take the liberty of copying from his and Dr. Latham’s work.!

GEOLOGICAL SECTION ACROSS JERSEY FROM Hast To WEsT.
FG h k
: H !

Length of section 11 miles.

a, Firm syenite. 64. Rotten syenite. c. Quartzite. d. Indurated shale. ¢. Shale.
Ff. Hornstone schist. g. Old conglomerate. 4. Newer conglomerate. 7. Sand-
stone. #. Raised beach. 7. Pebble beach. m. Blown sand.

The syenite, indeed, forms the basis of all the other rocks. It does
not, however, as might be supposed from the section, protrude at
three distinct points, the intermediate spaces being covered with
shale, but rather appears as three separate masses, in the north-west,
south-west, and south-east of the island. The first and largest of
these may be followed continuously along the coast from L’Etac,
round by Grosnez and Plemont Points to Point Sorel, and the
quarries north of St. John’s Church; it is traceable inland by the
quarries of Mont Mado, and a little south of the Wesleyan Chapel
called Les Freres, to the head of St. Mary’s Valley, near the fifth
milestone, and thence almost in a direct line to L’Etac. The second
mass occupies nearly the whole of the parish of St. Brelade, and
forms the coast-line from La Carriére opposite La Rocca Tower, in
St. Ouen’s Bay, to the Corbiéres rocks; and thence to a point a
little below Noirmont Manor House. The boundary of this mass
inland is generally covered on the west by blown sand, but it
appears again between Tabor Chapel and St. Aubin’s in the shape of
a granital of quartz and felspar, very subject to decomposition, in
which state it forms a fine china-clay. Quarries have been opened
here, and the clay is exported to England. From this point the
boundary may be traced 8.H. to the shore again under Noirmont
Manor. The third and last mass of the syenite forms the S.H.
corner of the island, and may be followed along the coast from Fort
Regent at St. Helier’s to La Rocque Point. It is interrupted at two
points, viz. at La Collette under Fort Regent, and in the headland
of Samares, by veins of hornblendic granital. Between La Rocque
Point and Mont Orgueil Castle the rocks are covered by the sands
of Grouville Bay ; but the syenite, which here passes into a granital
(quartz and felspar), may be traced inland by Gorey Church, and

1 The Channel Islands, p. 270. Geological maps of the islands there are none,
at least I have seen none, except the sketch-maps appended to Dr. MacCulloch’s
“ Account of Guernsey and the other Channel Islands” in the first volume of the
Geological Society’s Transactions. The Ordnance maps of Guernsey and Jersey are
on a scale of six inches to the mile, and somewhat expensive; but very good and

cheap pocket maps may be had of Guernsey, of Messrs. Staddon and Grigg, High
Street, St. Peter Port; and of Jersey, at any of the stationers there.

84 J. A. Birds—Greology of the Channel Islands.

along the upper road to Grouville, to the windmill above the village,
and thence to the neighbourhood of Sion House (where it is very
much decomposed)—and last to the quarry east of Victoria College,
and the rocks underneath the College itself. Between these three
great masses of syenite there lies upon the west a thick formation of
shale or schist (e), which extends without interruption from St.
Ouen’s Bay to the western or lower branch of the Val des Vaux, close
to St. Helier’s. At this point it is broken by an outburst of volcanic
rocks, which have altered it into a claystone porphyry, but it
appears again in an unaltered form a little north of Sion House, and
between Le Bourg and Petit Catillon, north of Grouville Church.
The general character of the rocks is that of a bluish-grey argillaceous
schist, with bands of hard grit. Sometimes (as near St. Helier’s) it
is a brown, sandy, finely-laminated shale. Occasionally I observed it
take a cherty character, as, e.g., near St. Aubin’s, on the right of the
main road to St. Brelade’s.

The north-eastern portion of the island is occupied by a formation
(f and g of Prof. Ansted’s section), variously composed of por-
phyries, hornstone-schist, altered sandstone, quartzite and quartzose
conglomerate, which extends in a wide belt-or broken arc from
Fremont Point, above Bonnenuit Bay, and L’Etaquerel, in Bouley
Bay, southward to within about a mile and a half of St. Helier’s;
and thence eastward by the Grand Val Mill, in the Val des Vaux,
till it appears upon the coast again between Anne Port and St.
Catherine’s Tower, in St. Catherine’s Bay. The points where it may
be best examined are the quarries at La Crete Point in the latter
bay, in a quarry a little north of Grand Val Mill, on the road from
the latter to La Boucterie, in Blanche Pierre Quarry, in the lower or
western branch of the Val des Vaux, in Bonnenuit Bay, and in the
quarries on the Jardin d’Olivet above Bouley Bay. 'The quartzite
and quartzose conglomerate are extensively quarried all along the
cliffs between these two bays.

Resting upon this formation (f and g), and occupying the whole
of the extreme north-eastern corner of the island, from a little
south of St. Catherine’s Tower, in St. Catherine’s Bay, to between
L’Htaquerel and La Tour in Bouley Bay, lies a newer argillaceous
breccia or conglomerate (i), composed mainly of chloritic slate and
ferruginous sandstone, but with blocks of syenite, granital, quartz,
and many other kinds of rock scattered throughout the mass. The
boundary of the deposit inland may be traced from a little west of
Carmel Chapel, on the road between the Jardin d’Olivet and Rozel,
and near the lodge of Rozel Manor, and thence to a point about
half-way between St. Martin’s Church and St. Catherine’s Bay,
where it may be seen resting upon the altered sandstone (f). The
finest sections, however, are those of the quarries at Verelut Point.
Both there, and all along the coast to Rozel—but particularly in
Port Saie—there are ample opportunities for its examination.

On the left of the road descending to Bouley Bay, and also, accord-
ing to Mr. Ansted, at the back of St. Catherine’s Bay, there are two
small patches of a still newer formation, consisting of a fine-grained

J. A. Birds—Geology of the Channel Islands. 85

red sandstone with clayey and ferruginous bands. In Bouley Bay
this sandstone rests unconformably, and almost horizontally, upon
nearly vertical strata of the older sandstone or hornstone (f). Prof.
Ansted believes this latest sandstone to be “ quite modern,” and to
have been “deposited before” (? shortly before), “or during the last
great elevation.”! He does not, however, assign any reasons for his
belief.

The age, indeed, of all these rocks is as yet a mystery. Nota
trace of fossils has been discovered either in the schist (e), or in the
sandstone portions of (f), or in the later sandstone (7); only among
the pebbles on the beach at Bouley Bay I found many containing
what certainly look like the remains of corals and portions of shells.
These have probably been derived from the newer conglomerate (h);
and if their organic character were determined, it might throw some
light on the age of the conglomerate. As yet, however, one cannot
even say whether the syenites are older or younger than the schist
(e), it not being known whether they ever enter and pierce the latter,
as in Cornwall the granites do the Devonian and Carboniferous rocks,
and are thereby proved to be younger than them. The direction of
the principal joints, nearly N. and §., is the same as that of the
granites in Cornwall, but, this being due to later causes, proves
nothing, of course, as to the age of the original formation of the rocks.

It is easy enough to invent theories as to the age and history of
the various formations; and, in the absence of further evidence,
this is about all that can be done. Dr. MacCulloch, in 1811, de-
scribed the schist as grauwacké,? 7.e. of Pre-Carboniferous age, and we
may perhaps pretty safely assume that it is of some Lower Silurian
period, coeval with the Silurian rocks of Normandy and Brittany.
(Llandeilo, Caradoc, or Lower Llandovery).

Of the sandstone, and its accompanying felstone and cherty
porphyries, and conglomerate (f and g), there is almost as little
evidence as to age. From their general appearance one might
imagine them to be of Old Red Sandstone equally as well as of
Permian or Triassic age. Only at one point, just above Le Bourg,
did I discover the shale (e) and the felstone porphyry (f) in
contact, and here it seemed to me that the shale actually overlay
the porphyry. Of course this might have been due to a fault or
inversion of the strata. But I can hardly think so in this case.
Can the porphyries have been eruptive and pierced into the shale ?

From the section it does not appear whether the shale is older or
younger than the sandstones and porphyries. Prof. Ansted con-
jectures, however, from the similarity of dip, that the newer Jersey
conglomerate (h) and the Alderney sandstone may be of the same
age; and, if so, that the older conglomerate (q) may perhaps belong
to the Cherbourg grits (Bunter or Lower Trias). In this case the
underlying porphyries and sandstones (f) might be somewhat older,
or intermediate between the schist (e) and the conglomerate (gq).

1 The Channel Islands, p. 275.

2 Account of the Geology of Guernsey and the other Channel Islands, Geol.
Trans. 1st series, vol. 1. 1st paper.

86 Notices of Memoirs—Prof. Liveing on Metamorphism.

This is about all that conjecture at present can arrive at. There
would seem indeed to be little hope of determining the question as
to the age of the rocks from a study of the island alone, or of all
the Channel Islands together by themselves. It can only be by
comparison of their geology with that of the neighbouring parts of
the Continent—of Normandy and Brittany—that we can expect a
solution of the problem.

In addition to the syenites, and the sedimentary and porphyritic
rocks above described, there is a very important accumulation of
volcanic rocks (trap, porphyry, and amygdaloid), in the immediate
neighbourhood of St. Helier’s, and which does not seem to have
been noticed either by Dr. MacCulloch or Prof. Ansted. Com-
mencing at Gallows Hill, on the west of the town, the series may
be traced for about two miles northward, across both branches of
the Val des Vaux, to near the Grand Val Mill. It occurs again
between the two houses called the Hermitage and Bagatelle,
in the quarry east of Victoria College, and at the foot of St. Saviour’s
Hill. It may be well seen in the quarries at the bottom of Gallows
Hill, and on the road up the western branch of the Val des Vaux,
where the focus of the eruption seems to have been. ‘There is
nothing to indicate the age of these rocks except the alteration of
the shale (e) in their neighbourhood (as, e.g., on the Trinity Road,
and other places) into a claystone porphyry, proving them to be
more recent than it. The mention of this altered rock leads to
another and final question; namely, what is the cause of metamor-
phism in the various rocks of Jersey? It is not the syenite: for
at, or close to, its junction with the shale (as, e.g., on the ascent by
the path from St. Aubin’s into the St. Brelade’s Road), the latter is
quite unaffected.

The volcanic rocks may account for the alteration of the shale (e)
into claystone-porphyry ; but they do not account for the felstone
and hornstone-porphyries (f), which exhibit the same character,
both in thé immediate neighbourhood of the trap (e.g. in the quarry
N. of Grand Val Mill), and miles away from it (eg. at La Crete
Point, in Blanche Pierre Quarry and in Bonnenuit Bay). These
would seem to be porphyries belonging properly to the sandstone
series (f), but whether contemporaneous or intrusive J am unable
to say. Here again the study of the geology of Normandy and
Brittany is essential to the understanding of that of Jersey and the
other Channel Islands.

INiOrEet GS), @2a)) sIMesVE@ ire Se
On tHe Meramorpuism oF THE Rocks oF THE CHANNEL ISLANDs.
By Prof. Ltvztne, etc., etc.

PAPER was recently communicated to the Cambridge Philo-
sophical Society (Oct. 29th, 1877) by Prof. Liveing, in which

the author traced the connexion of the rocks in Guernsey, and
pointed out the extreme variations in the amount of change these
rocks and some of those in the other islands had undergone, from

Reports and Proceedings— Geol. Soc. London. 87

well stratified gneiss to highly crystalline syenite. He attributed
the coarsely crystalline structure of these and other granitic rocks to
long-continued variations either of temperature or of the action of
some partial decomposition, such as steam or other gases may be
supposed to effect, rather than to fusion; and he pointed out that
there were granitic veins in the islands which appeared to have
originated like ordinary quartz-veins, while others were intrusive,
and concluded that the granitic structure was a result of metamor-
phosis, and that the proof of the igneous origin of a granitic rock
must be determined by considerations independent of its crystalline
character.

ASV sti Sn sans) JV ANfaD) 2=154S\(S@128 a DabsN Ke IS
aad
GerotocicaL Socrery or Lonpon.—December 19th, 1877.—
- Prof. P. Martin Duncan, M.B., F.R.S., President, in the Chair.

The following communications were read :—

1. “On Argillornis longipennis, Owen, a large bird of flight, from
the Eocene Clay of Sheppey.” By Prof. Owen, C.B., F.B.S.,
F.G.S., ete.

In this paper the author described some remains of a large bird
obtained by Mr. W. H. Shrubsole from the London Clay of Sheppey,
consisting of parts of fractured humeri belonging to the right and
left sides of the same species or perhaps individual, and including
the head of the bone, with portions of the upper and lower parts of
the shaft. The texture of the shaft, the thinness of its bony wall,
and the large size of the cavity recall the characters of the wing-
bones of the large Cretaceous Pterodactyles. ‘The author indicated
the characters which led him to regard the remains under considera-
tion as those of a volant bird, most nearly approaching the genera
Pelecanus and Diomedea; and as the evidence derived from the
cranium of Dasornis would indicate a bird too large to be upborne
by wings to which these bones might have belonged, whilst the
skull of Odontopteryx is far too small to have formed part of a bird
with wings as large as those of the Albatross, and Lithornis and
Pelargornis are excluded by the characters of their remains, the
author concluded that the bones obtained by Mr. Shrubsole fur-
nished indications of a new genus and species of flying birds, for
which he proposed the name of Argillornis longipennis. He regarded
it as probably a longwinged natatorial bird, most nearly related to
Diomedea, but considerably exceeding the Albatross (D. exulans) in
size. The author remarked that the generic name Megalornis, pro-
posed by Prof. Seeley for the Lithornis emuianus, Bowerb., had been
preoccupied by the late Mr. G. R. Gray.

2. “Contributions to the History of the Deer of the European
Miocene and Pliocene Strata.” By Prof. W. Boyd Dawkins, M.4A.,
HR.S., E.G.s:

The author commenced by referring to the difficulties attending
the study of the Huropean Miocene and Pliocene Deer, and indicated
that the majority of the known antlers may be referred to two cate-

88 Reports and Proceedings—

gories—an earlier or Capreoline, and a later or Axidine type. To
the Carreomt he referred the following species :—Dicroceros elegans
Lart. (=Prox furcatus, Hemel), Cervus dicranoceros, Kaup (in-
cluding C. anoceros and trigonoceros, Kaup), and Cervus Matheronis,
Gerv. (=C. Bravardi), from the Miocene, and Cervus australis,
Gerv., and C. cusanus, Croizet & Jobert, from the Pliocene. To the
Axerpes belong Cervus Perrieri, Cr. & Job. (including C. issiodorensis
and pardinensis, of the same authors), C. etneriarum, Cr. & Job.
(=C. rusoides, Pom., and C. perollensis and stylodus, Brav.), C.
suttonensis, sp. n., and C. cylindroceros, Brav. (including C. gracilis,
Bray.), all from Pliocene deposits. Besides these, the author noticed
a species incerte sedis under the name of Cervus tetraceros, Dawkins,
which he regards as coming nearest to the Virginian Deer, or Caria-
cou (Cariacus virginianus). From the examination of the antlers of
these species he indicates that in the Middle Miocene age the cervine
antler consisted of a simply forked crown, whilst in the Upper -
Miocene it becomes more complex, although still small and erect,
like that of the Roe Deer. In the Pliocene it becomes larger and
more complex, some forms, such as the Cervus dicranios, Nesti,
being the most complicated of known antlers. The successive changes
are analogous to those observed in the development of the antlers of
the living Deer with increase of age. In the Miocene we have the
zero of antler-development, and the Capreoline type is older than
any other. The nearest living analogue of the Miocene Deer is,
according to the author, the Muntjak (Styloceros), now found only
in the oriental region of Asia, along with the Tapir, which also co-
existed with Cervus dicranoceros in the Miocene forests of Germany.
The Pliocene Deer, again, are generally most nearly allied to the
oriental Axis and Rusa Deer, the only exception being Cervus
cusanus, the antlers of which resemble those of the Roe, an animal
widely spread over Europe, and Northern and Central Asia. The
alliance of these Pliocene Deer with those now living in the Indian
region is regarded by the author as a further proof of the warm
climate of Europe in Miocene times, confirmatory of the conclusions
arrived at by Saporta from the study of the vegetation.

3. “On the Occurrence of Branchipus (or Chirocephalus) in a fossil
state, associated with Archeoniscus, and with numerous Insect-remains
in the Eocene Freshwater Limestone of Gurnet Bay, Isle of Wight.”
By Henry Woodward, Hsq., F.R.S., F.G.S.

The remains of Crustacea and Insects noticed in this paper were
obtained by Mr. E. J. A’Court Smith from a thin bed of limestone
belonging to the Osborne or St. Helen’s series at Thorness and
Gurnet Bay in the Isle of Wight. The collection is the result of
about twenty years’ work. The insect-remains comprise about fifty
specimens of Diptera, including wings of Tipulide and Culicide,
and the pupa apparently of a Gnat, one wing of a Hemipterous
insect, and a flattened Homopterous insect identified by Mr. F.
Smith with Triecphora sanguinolenta; two specimens referred to the
Lepidopterous genus Lithosia ; only three Orthoptera, one a Gryllo-
talpa, the other two belonging to a Grasshopper; thirty-five Hymen-

Geological Society of London. 89

opterous wings, thirty-three of which are referred to Ants of the
genera Myrmica, Formica, and Camponotus; twenty-three examples
of Neuroptera referred to Termes, Perla, Libellula, Agrion, Phry-
ganea, and Hemerobius; and twelve of Coleoptera, including species
of Hydrophilus, Dytiscus, Cureulio, Anobium, Dorcus, and Staphy-
linus. There were also two Spiders. Several species of bivalved
Entomostraca have also been obtained from these deposits, and
identified by Prof. Rupert Jones. Of the Branchipod Crustacean
both sexes are fossilized and beautifully preserved, the males show-
ing their large clasping antenne, and the females their egg-pouches,
with large and very distinct disk-like bodies representing the com-
pressed egos. Dr. F. Goldenberg notices a fossil from the Coal-
measures of Saarbriick which he regards as a Branchipod, and describes
and figures under the name of Branchipusites (recté Branchipodites)
anthracinus ; but this interpretation of it is at least doubtful. The
author names his species Branchipodites vectensis. ‘The Isopods
accompanying this species are referred to the genus Archeoniscus,
M.-Edw., and one of them is identified with the Paleoniscus Brong-
niarti of Milne-Edwards. The other is probably a new species,
perhaps nearly allied to the existing Spheroma serratum.

4. “The Chronological Value of the Pleistocene Deposits of
Devon.” By W. A. E. Ussher, Esq., F.G.S., of H.M. Geological
Survey.

In this paper the author endeavoured to work out. the sequence of
events indicated by the Pleistocene deposits of Devonshire. He
believed that during late Tertiary times subsidence extended to the
south-western counties, and to this he ascribed with some doubt the
accumulation of a patch of gravel on the north summit of the Black
Downs and of part of the old bone-breccia of Kent’s Cavern. In
the Glacial period, with the increase of cold, snow accumulated on
the high lands, with formation of glaciers, which descended and united
to form a great ice-field, planing the surface of a district composed
chiefly of Cretaceous and probably Tertiary strata. To this period
the author ascribed the formation of the clay with unworn fragments
of flint and chert, and doubtfully part of the clays of the Bovey
Valley, the clay of Petrockstow, and part of the bone-breccia and
the crystalline stalagmite of Kent’s Cavern. The Postglacial pheno-
mena he referred to three subperiods, in the first of which, during a
gradual amelioration of the climate and disappearance of the ice,
large quantities of surface-water were set free, redistributing and
removing Tertiary outliers, partially destroying the old ice-beds, and
moraine rubbish, and sweeping Secondary deposits from Palaeozoic
districts. The deposits then formed were supposed to be the old
gravel patches of Colford and Orleigh Court, the waterworn materials
on the Blackdowns and Haldon, the sands flanking the Bovey Valley,
and, with doubt, the redistributed Triassic pebble-beds of Straight-
way Hill, and part of the cave-earth of Kent’s Cavern. The next
subperiod he regarded as one of great fluviatile action, the land being
higher than at present, though sinking, and the meteorological con-
ditions such as to greatly increase the volume of the rivers. The

90 Correspondence—HNessrs. Blake and Hudleston.

subsidence having continued to the level of the present raised beaches,
reelevation took place, producing greater cold and more extreme
seasons. and culminating in the production of continental conditions,
permitting the southward migration of a temperate fauna, and the
advent of one requiring greater cold. During this period the gravels
connected with the formation of the present valley system, the raised
beaches, and the “Head” were produced, and, doubtfully, part of the
cave-earth and the granular stalagmite of Kent’s Cavern, and the clay
of Petrockstow and Roundswell. In the last subperiod the author
considered that a subsidence took place during which most of the
valleys were excavated to their present depth, and forest growth took
place upon the old marine plain; the forests were then gradually cir-
cumscribed by the encroaching sea and diminishing rainfall, which
also led to changes in the streams, and finally the sea entombed the
forests and swamps on the coasts, and produced the present cliff-line.
The results of this period are the submarine forests, most of the
river-valley gravels, and alluvial tracts bordering the present river-
courses.

> CORRESPONDENCE.

———
THE CORAL RAG OF UPWARE.

S1r,—In the October Number of the Gxonocican Macazinu
Professor Bonney points out certain facts observed originally by Mr.
Henry Keeping—but subsequently confirmed by himself—which are,
he considers, incompatible with “the presumed section” near Upware
given in our paper ‘On the Corallian Rocks of England,” Quart.
Journ. Geol. Soc., vol. xxxiii. p. 315.

Our object in attempting the section referred to was to show how
the paleontologically higher beds of the south pit could overlie those
of the north pit—though they dip towards them; and that they may
do so, unless we call in the aid of a fault, the existence of a synclinal
is the most natural supposition. Beyond this, the stratigraphy was
irrelevant to our paper—and we readily admit that the unconformity
between the Corallian rocks and the newer strata might have been
more clearly shown. We would mereiy remark that Mr. Keeping’s
section, being at right angles to ours, can throw no light on its
correctness.

The true reading of the sequence of the Corallian rocks—which,
as indicated in column ix. of our table of comparative sections, is
not seen—rests entirely on paleontological evidence, and _ this,
though he admits that we may be right ‘in assigning to the rock of
the northern pit a lower horizon than that of the southern,” Pro-
fessor Bonney considers not to be strong. Here then is the only point
really at issue between us. We can only say that the two urchins
which by their abundance characterize the northern pit, are “ species
usually indicative of a low position” (see our memoir, p. 867), and
their occurrence on or above the horizon of a Rag fauna would be
another of those surprises with which we will admit the Corallian
series abounds.

Correspondence—Messrs. Blake and Hudleston. oe

The second portion of Prof. Bonney’s paper relates to another
matter ; and here let us at once express our regret that any phrase-
ology of ours should even seem to imply that the Coral Rag of
Upware had been “imperfectly” treated in his “‘ Geology of Cam-
bridgeshire.” Having said this, we will proceed to discuss the °
substance of his complaint. The chief points in which our account
differs from that of Prof. Bonney are the assignment of the Upware
rock of the south pit to the Coral Rag in a restricted instead of a
general sense; and the separation of the north pit rock as belong-
ing, not to a mere variation of development, but to a different
horizon. That Prof. Bonney called the Upware rock “true Coral
Rag, as the word was then understood,” was clearly acknowledged
in the sentence following the one he quotes, viz. “It has always
been called Coral Rag, except by Mr. Seeley.”’ But Prof. Bonney
went further. He attempted to show to what part of the “Coral
Rag as then understood” the Upware rock belongs. He assigned it
to the lower part, and therefore to an horizon beneath our restricted
“Coral Rag” ;! and it is on this point that we differ from him. He
did this on account of its containing Cidaris florigemma, which he
says extends down to the Lower Calcareous Grit. We ask, where ?
Not, we venture to say, in England.

To prove a negative is of course a difficult task, and the experience
of years may be upset by the discovery of a moment. But the fact
is that Cidaris florigenma hardly ever occurs even in the Coralline
Oolite, which in nearly every locality where a sequence can be
traced is interposed between the Coral Rag and Lower Calcareous
Grit. So far, then, from making the position of this urchin less
constant than it was supposed to be, as is alleged by Prof. Bonney
in the second paragraph of his letter, our intentions were certainly
in a contrary direction, only we find it constant in the upper and not
in the lower part of the series; or, to speak more accurately, it is
most plentiful in the lower portion of the upper division, i.e. the
restricted Coral Rag. If, however, English geologists are content
to derive their impressions of the distribution of the Mesozoic strata of
their own island from the detailed accounts of their supposed foreign
equivalents by continental authors, we can never get any real data
for comparison. In the present instance it would appear that the
Cidaris florigemma was contemporary with the earlier part of the
Coral growths in Eastern France. In the Boulonnais it was pretty
uniformly distributed throughout, as M. Rigaux informs us, and
he therefore wonders that we consider its position so constant.
In England again, except in the Weymouth area, which shows more
. intermediate conditions, it is almost entirely confined to the upper-
most Coral growths. The lower reefs at Highworth and Hackness,
though presumably formed under similar physical conditions, are

1 It may be necessary here to remind the readers of the Gzox. Mace. that the
Corallian of England admits of four primary subdivisions, as follows in descending
order: 1. Supracoralline, or equivalents of the Upper Calcareous Grit; 2. Coral
Rag, or zone of Cidaris florigemma; 3. Coralline Oolite, or zone of Am. plicatilis ;
4. Lower Calcareous Grit, or zone of Am. perarmatus.

92 Correspondence—Dr. O. Feistmantel.

without it. Whether we are to consider that Coral growth began
earlier in England than in France, or that Cidaris florigemma reached
us later, is an interesting question; but this much is certain, that the
Coral growths continued to a much later period in Eastern France ;
hence the idea that Cidaris florigemma is indicative of a low
Corallian horizon. In the discussion on our paper, Professor Morris
pointed out that ‘the so-called Corallian occupied different zones in
different localities on the Continent, stretching, in fact, from the
Oxfordian to the Portlandian inclusive.” Correlation, to be of any
value, therefore, is only to be effected by a detailed examination of
both the English and continental areas, without confounding to-
gether either the beds of different districts, or those of the same
district, as is generally done in all works dealing with the subject.

Lonpon, Dec. 6, 1877. Buake AnD HupLEsTon.

P.S. The great stretch of country passed under review in the
“‘Corallian Rocks of England” obliged us to condense lists of fossils
as much as possible. Had we given a full list of fossils from the
North Pit, it is difficult to see that any doubt as to its age could
exist. The following, omitting certain indefinite forms, is as full a
list as we have been able to put together :

Ammonites perarmatus Isocardia (cast)
90 plicatilis Pygaster umbrella
Littorina muricata (var.) Echinobrissus scutatus
Pleurotomaria (cast) Holectypus depressus
Gervillia aviculoides Collyrites bicordatus
Opis Phillipse
Only three of these occur in the South Pit. B. & H.

CYCADACKOUS PLANTS OF THE DAMUDAS.

Srr,—I beg you will allow me space to correct some erroneous
impressions that might be made by certain not sufficiently explained
statements published by me in the Guotocican MaGazine, and
elsewhere, and to apologize to the gentlemen whom I thereby
have. had the misfortune to offend. I beg to state that any such
effect was as far from my intention as it certainly would be contrary
to my interests, and I regret that, when stating facts, I did not
more fully notice circumstances that would only be known to those
immediately concerned.

The following instances will sufficiently explain this unfortunate
misunderstanding.

When writing in the GrontogtcaL Magazine in November, 1876,
p. 489, on the occurrence of Cycadeaceous plants in the Damudas, ~
saying in footnote No. 10 ‘“‘that they were known long ago,” I ought
to have explained that the two species (out of three) I mentioned,
i.e. Néggerathia, near Vogesiaca and Glossozamites, although collected
some years since, have not before been determined as such, and only
Néggerathia ? Hislopi was by its describer (Sir Ch. Bunbury) con-
sidered as doubtfully Cycadeaceous, and I see now that my footnote,
No. 10, should have been written thus: “that Cycadeaceous plants

Correspondence—MUr. G. Linnarsson. 93

were collected—but not described,” for which I beg to apologize to
Mr. W. T. Blanford.

Mr. W. T. Blanford’s remark “that Cycads have not hitherto
been found in the Damudas” was therefore in so*far correct as the
mentioned specimens, with the exception of Néggerathia? Hislop,
although found have hitherto not been determined until I did so.

I should also, when writing in the September Number of the Grot.
Mage. 1877, p. 431, that “Zamia Burdwanensis, McClell., has been
described as long ago as 1850,” have added that the affinities of this
species had been later disputed for many years, Dr. Oldham suppos-
ing, from the material at his disposal, that a Schizoneura has been
mistaken for a Zamia, until, through the recovery of the original
specimen, this species was proved to be indeed a Zamia. (1
described this species fully, with its history, in Rec. Geol. Surv. of
India, 1877, vol. x. No. 2.)

I wrote in the November Number of the Gor. Maca. 1876,
already referred to: ‘‘ From the occurrence of the genus Glossopteris
in these beds (Damudas), they have been for a long time brought
into connexion with the Australian Coal-measures, and declared
without any proof as probably Paleozoic,” and I referred to Dr.
Oldham, Mr. H. T. Blanford, and Mr. W. T. Blanford as authorities.
This was the impression left upon me after the perusal of the papers
referred to—but I should have explained that besides Glossopteris,
some other fossil plants also were mentioned as correlating fossils.
I express my regret for having left these other correlations uncon-
sidered, but I hope to be able to explain this point further in the
Flora of the Lower Gondwanas in India. This note refers to all
my publications on this subject. OrrokaR FEIsTMANTEL.

Cateurra, Oct. 9, 1877.

PROFESSOR MILNE AND THE GLACIAL PHENOMENA OF
SCANDINAVIA.

Srr,—It is not without great astonishment that I—and, I think,
most geologists who have devoted any attention to the post-Tertiary
formations of Northern. Hurope—have read a paper by Professor
John Milne in your last July Number.' By some observations made
from the railway waggon, or the steamer, when travelling through
Sweden and Finland, he thinks himself enabled to refute the views
since many years universally held by Scandinavian geologists
respecting the surface geology of the country. The features usually
attributed to the action of glaciers on a continental ice-sheet—as,
for instance, the polished and scratched rocks and the boulders—he
thinks better explained by the action of coast-ice. If Professor
Milne had stayed a day in Sweden, and made an excursion with a
Swedish geologist, I hardly doubt that the first part of his Travelling
Notes would have been unwritten, for it seems impossible that a
person with such good reasoning powers should hold the views
advocated in those notes, after seeing a few of these scratched rocks

1 J. Milne: Across Europe and Asia. Travelling Notes. Part I. London to St.
Petersburg. Gzou. Mac. Dec. II. Vol. IV. p. 289 seg.

94 Correspondence—Mr. Gt. Linnarsson.

and the associated phenomena near enough, and having their bear-
ings pointed out to himself by an experienced guide. As they have
now been written, and published in a Journal of such a standing as
the Gronoctcat MaGazine, they ought not to be altogether un-
answered, though I think that most of your readers do not need to
have the failings of such reasonings pointed out.

The chief argument of Professor Milne against the glaciation
theory seems to be that that theory requires great climatal changes,
the explanation of which would involve insuperable difficulties. I
admit that Science has not yet given a final explanation of these
changes, but they are a well-established fact, and a fact must be
accepted, whether we can explain it or not. As for myself, I think
that the physical features—such as the nature of the Till and the stria-
tion of the rocks—are in themselves sufficient proofs of a former glacial
climate, but there are, besides, ample palzeontological evidences. Some
thirty years ago, Professor Lovén found that certain shell-banks in
Southern Sweden contain a completely Arctic fauna, and the labours
of the Geological Survey of Sweden have shown that the stratified
clay reposing on the gravel-beds is everywhere characterized by the
well-known shell Yoldia arctica, Gray, which occurs living only in
the most Arctic regions, as the coasts of Spitzbergen and those of
northern Greenland. Still more striking proofs of a former glacial
climate have been, in later years, adduced by Dr. Nathorst, who has,
from débris in the lacustrine deposits, found that a vegetation
identical with that now prevailing in Spitzbergen (Dryas octopetala,
Salix polaris, ete.) once lived not only in the lowlands of Southern
Sweden but also in Denmark. This being the case, it cannot be
doubted that a climate cold enough to produce a continental ice-sheet
once prevailed so far south as in Southern Sweden.

That, actually, Till is formed, and rocks polished and striated by
glacier-ice, is so well known from observations in the Alps and
elsewhere, that I think Professor Milne himself cannot deny its
capability of producing such effects. He points, however, to one
circumstance, often observed in connexion with these phenomena,
which he thinks not accountable for by the action of glacier-ice,
viz. the occurrence of erratic blocks raised to positions above the
rock from which they were derived. He explains their occur-
rence by the “action of coast-ice upon a rising area.” If there
should be any meaning in this, Professor Milne ought to have called
for a sinking area instead of a rising, as, of course, the question
must be of the relative height. If a block is attached to floating-
ice, and the land is rapidly sinking, the block may be deposited in a
relatively higher position than that of the parent rock, but not if
the land is rising. There are, however, many instances of blocks
derived from lower positions, in places where the water never
reached. Thus, in Westrogothia blocks of the Cambrian Sandstones
are often found. reposing on the summits of the Silurian mountains,
several hundred feet above their parent rocks, on heights which
the sea never reached in post-Tertiary times; and many similar and
still more striking instances are recorded from other countries by

Correspondence—Ir. G. Linnarsson. 95

Térnebohm, James Geikie, and other observers. In such cases it is
quite impossible to admit floating-ice as the working cause, and
we must recur to glacier-ice. It is not here the place to discuss
the physical conditions which produce these effects; it is enough to
point to the fact.

Tf it is thus evident that the phenomena in question can have been
effected by the action of a continental ice-sheet, it remains for us to
show that they cannot have been effected in the manner advocated
by Professor Milne.

That the Till—which in no part of Sweden is more developed than
in the south—cannot have been’ formed by the action of floating-
ice, is evident to any one who has seen some sections of that deposit,
with its striated blocks, heaped confusedly together in the tough
tenacious mud. We have, in Sweden, in many places, gravel-beds
which have evidently been deposited by shore action, but they have
quite another aspect ; the gravel is more or less stratified, the stones
are rounded, not scratched, and the fine mud is washed off, so that
. this gravel is far less coherent than the Till. The scratches in the
rocks are usually best marked below the Till, and it is therefore
probable that the result is from the same cause. That they cannot
result from the action of coast-ice is evident from many reasons.
Firstly, it is impossible to conceive how the scratches could have
such a constant direction in large regions, if they were produced by
coast-ice. Professor Milne himself correctly remarks, that the
directions of the scratches “point seawards, or else to the lowest
land,” but,'strangely enough, he adds that this circumstance is
rather more favourable for his own views. Everybody, however,
knows that glacier-ice moves downwards, and therefore it is natural
that the scratches, on the whole, have that direction, if produced by
glacier-ice. On the contrary, if produced by coast-ice, their direc-
tion is independent of the slope of the land, and must vary according
to the currents and the winds. Further, in the isles along the Baltic
coasts of Sweden, the striation and polishing is most marked on
their landward face, from whence the glacier must have come,
whereas their outer sides ought to have been more polished and
scratched, if the coast-ice had produced these effects.

It cannot be denied that, as Professor Milne says, the abrading
action of coast-ice is an undoubted fact, but it must be remarked,
that in the coasts of Sweden and Finland, and especially near the
route followed by him, this action is excessively small. The rocks
are there so hard and compact, and the force of the waves so small,
that their action on the rock-surface is hardly perceptible. A rock
may be exposed there for hundreds of years to the waves, without
the finest scratches being abraded. Professor Milne thinks that, to
be preserved, they ‘must always have remained above sea-level, or
else have been shielded by some protective covering during both
subsidence and elevation,” but it is so far from this being the case
that, on the contrary, the scratches are much better preserved
beneath the water than in the open air a few feet above it. In the
open air the scratches usually become obliterated in a few years by

96 Correspondence—Mr. Charles Callaway.

the action of the atmospheric agents, and, above all, by the lichens.
This is also the reason why the smaller islands and the lower
portions of the larger ones, as Professor Milne remarks, are of a
whitish colour. As long as the waves hinder the lichens from at-
taching themselves to the rock, it preserves its scratched and
polished surface, but when elevated a few feet above the sea-level,
it soon becomes rough and dark. In places that were sheltered from
the action of the glacier-ice, the rock is never polished and scratched,
though on our coasts these places are usually the most exposed to the
action of the waves and to coast-ice.

' Gxrotoctcat Survey OFrFice, G. LInnARSSON.
StockHoim, November 30th.

DEVONIAN GEOLOGY.

Str,—One is scarcely surprised to find that the papers of Messrs.
H. B. Woodward and C. Reade, in the last October Number of the
GrotocicaL MaGazine, afford such strong support to the masterly
interpretation of the Geology of Devonshire given to the Geological -
Society by the late Professor Jukes and published at his own
expense.

Professor Jukes’s knowledge of the Irish rocks with which he
classed those of Devonshire, together with his powerful and practised
ability for field observation, entitled his opinions to more considera-
tion than at the time they appeared to receive.

Now that he is gone, it is gratifying to see his ‘able outline’
being ably filied in with careful details, and should the further
revision still bear out his views, this will show how apt was a
remark he often made regarding puzzles in field geology, ‘“ Put all
the evidence down, and it will explain itself.”

Wisstyan, Nov. 19th, 1877. BENWYAN.

THE VOLCANIC ROCKS OF SHROPSHIRE.

Str,—Mr. §. Allport, in his valuable paper “On Certain Ancient
Devitrified Pitchstones and Perlites from the Lower Silurian District
of Shropshire ” (Quart. Journ. Geol. Soc., vol. xxxiii. part 3, August,
1877, p. 449), read May 28rd, 1877, announced the discovery of the
bedded character of the so-called ‘“‘ Greenstone” of the Wrekin. The
same fact was communicated by me to the Society on March 21st,
1877, in my paper “On a new area of Upper Cambrian Rocks in
South Shropshire,” which however did not appear until the publica-
tion of part 4 of the Quart. Journ. Geol. Soc., in November, 1877,
p- 652. The value of this discovery will be seen when it is remem-
bered that these “ Lower Silurian” rocks are really Cambrian, some
of them clearly as ancient as the Lingula Flags, if not Menevian,
and that they rest upon the bedded volcanic series unconformably. 1
am working out the details of this great formation, but shall not
publish until I have collected further materials.

CHARLES CALLAWAY.
WELLINGTON, SALoP, Dec. 11th, 1877.

THE

GEOLOGICAL MAGAZINE.

NEW SERIES: @ DECADE II. VOL.

No. II—MARCH, 1878.

ORIGINAL ARTICIES.

— ————

T.—On a Connection oF Pretstocenre Mammats DrEepGED OFF THE
Hastern Coast.

By Wrii1am Davizs, F.G.S. ;
of the British Museum.

F the many private collections of vertebrate fossils found on
or off the coast of the Eastern counties, none surpass in paleon-
tological and also in geological interest the fine collection made
with much zeal and care by Mr. J. J. Owles, of Yarmouth, in-
asmuch as the larger portion of the specimens are exclusively the
remains of Postglacial Mammals, and were brought up in the
fishermen’s dredge, either from, or in close proximity to the well-
known Dogger Bank, thus proving conclusively the existence of
submerged Pleistocene or Postglacial land lying off the Hastern
coast in the North Sea. Prof. Boyd Dawkins is the only author,
as far as | am at present aware, who has made any reference to this
really valuable series of remains, and then only incidentally in his
memoir, “On the Distribution of Postglacial Mammals.” !

The collection having been deposited in the British Museum,
where of necessity it will be absorbed and distributed in the general
collection, and its unity be lost; is worthy of being placed upon
record as a whole, on account of the interest it possesses in relation
to the geological history of the bed of the sea lying off the Norfolk
coast. The species represented in it are—

Ursus, sp. Bos primigenius, Boj.

Canis lupus, Linn. Bison priscus, Bo}.

Hyena spelea, Goldf. Equus caballus, Linn.
Cervus megaceros, Hart. Rhinoceros tichorhinus, Cuv.
C. tarandus, Linn. EHlephas primigenius, Blum.
C. elaphus, Linn. Castor fiber, Linn.

Cervus, sp. Trichechus rosmarus, Linn.

and some large vertebree of Cetaceans of a later date. The collection
contains altogether about 300 specimens. Of these the remains of
the Mammoth are most numerous, exceeding one hundred specimens,
and consisting of portions of jaws, detached molars, tusks, bones of
the trunk and limbs. Of separate teeth and jaws there are upwards
of seventy, representing nearly as many individual Mammoths; of
tusks there are four, one of large size, but imperfect; three quite
perfect, but of comparatively young animals, each of which shows
1 Quart. Journ. Geol. Soc. vol. xxv. p. 192.
DECADE II.—VOL, V,—NO. III. 7

98 Wilham Davies—Pleistocene Mammalia.

the characteristic spiral curve. Of the first or milk series of teeth
there are but few in the collection; the larger portion of the true
molars are of aged adults, for the ultimate molar alone is represented
by twenty-four specimens, many of large size, and some much worn.
They nearly all exhibit the typical characters and structure of the
teeth of the Siberian Mammoth; the enamelled plates being thin,
numerous and closely set.

The Tichorhine Rhinoceros is represented by a fine skull nearly
perfect, and containing a series of five molars on the right side, and
the fourth premolar on the left; the cranial portion of another skull,
detached teeth and bones. The skull is interesting as showing an
extensive fracture of its facial portion, just in front of the interorbital
platform, and just clearing the anterior orbital rim. The fracture
had subsequently healed, but had left a large scar on the bone,
causing a deflection of some three or four degrees from the median
line of the cranium. This deflexion also extends, but in a greater
degree, to the palate and premaxille; it has also affected the nasal
septum, which has been forced on one side and its symmetry de-
stroyed, being convex on one side, and concave on the other. The
animal appears to have lived long after receiving this fearful injury,
probably derived in an encounter with one of its own kind, or with
one of the huge Mammoths its contemporaries.

The remains of the Reindeer (Cervus tarandus), consist of a
cranium, wanting the facial portion, a ramus of a mandible and
portions of antlers, one a beam more than four feet in length. The
species above noticed only occur in deposits of Postglacial age, the
other species given in the list above as having been found with them
are common both in Pre- and Postglacial formations.

The remains of the Carnivora, usually rare in river or other
aqueous deposits, are few in number, consisting only of the ramus of
a mandible of the Hyzena, a skull and cervical vertebree of the Wolf,
and a femur of the Bear, the species undetermined. The Cervide
are represented by crania of two males and a female of the great
Trish Deer (Cervus megaceros) ; crania of the Red Deer (C. elaphus),
and also several vertebrae and portions of antlers of species not
determined. The Bovide are represented by horn-cores, teeth, verte-
bree and limb-bones, and the Horse by the occipital portions of two
skulls, and bones of the trunk and limbs.

The finely-preserved mandible of the Walrus, with the exception
that the coronoids are wanting, and that the teeth have fallen from
their sockets, is in every other respect perfect. Its age may be a
moot point; nevertheless, from its state of fossilization and external
colouring, which are the same as many of the undoubted fossil bones
and tusks with which it was found associated, I am led to claim for
the Walrus a place in our lists of British Pleistocene Mammals, where
it has hitherto not been admitted, though Mr. Thomas Southwell,
in an interesting paper upon this animal in “Science Gossip,” for
January, 1877, p. 3, states that “the skull has been found in the
peat near Ely.” If this find can be authenticated, it has as good a
claim to be regarded as a British fossil as the Grampus skull dis-

William Davies—Pleistocene Mammalia. 99

covered in the Fens of Lincolnshire and described by Prof. Owen
in his “British Fossil Mammals.” Its fossil remains are also said
to be found in France; and in the Crag, enormous incisors of
probably a closely allied animal (Trichechodon, Lank.) are far from
uncommon. Like the Lemming and other land animals, the Walrus
may have migrated from our shores when the climate and waters
were no longer congenial to its existence.

The skull of the Beaver, though undoubtedly fossil, may have
been a later introduction; and the bones of the larger Cetacea I
regard as semi-fossil bones of Post-Tertiary age.

It-is Mr. Owles’ impression that any large collection of similar
fossils will never be made again from the area in which his collec-
tion was obtained. The Dogger Bank for many years, he states,
has been so scraped and sifted by the fishermen’s dredge, that a™
tooth or a bone is now seldom brought to the surface on it.

From Preglacial deposits there are a few teeth of Hlephas
antiquus and Elephas meridionalis, of this species there is a fine
entire germ of an ultimate lower molar.

In the collection, and obtained from the same sea area, I dis-
covered the centrum of an anterior caudal vertebra of an Iguanodon,
which must have come from a much older deposit. Externally it is
indistinguishable from the other bones, having the same deep brown
colour, and its surface is covered with the shells of small Balani,
tubes of Serpule, and cells of Polyzoa, but its mineral condition is
very different, petrefaction being complete, all its cellular tissue
being permeated by foliated sulphate of lime, resembling in this
respect. many Dinosaurian bones from the Wealden of the Isle of
Wight; and thus giving it a Wealden rather than a Lower Green-
sand facies. But whatever the deposit from which it was obtained,
it has not been transported from a distance, for it has been subject
to no water-wearing action; the epyphysial rugosities at either end
are very Slightly worn, and the natural margins are intact, as is
also tlie chevron bone depression ; the walls of the neural arch are
present, but the top with the process is absent. The fractured
surfaces of the neural walls show the splintery fracture of a recent
bone, with the points very slightly abraded, as if the spine had been
broken off before fossilization had commenced. This interesting
fragment is a geological puzzle; that it was originally deposited
where it was discovered is proved by its angularity, and there is no
doubt as to its species, which is also limited to the Wealden and the
Lower Greensand. Its mineralization points to the former as the
bed from which it was probably derived, yet there is no present
evidence that the formation extends to the Norfolk coast. The
officers of the Geological Survey employed upon that district may
possibly solve the difficulty.

Of the Norfolk coast fossils, the British Museum acquired in
1842 and 1845 the collections made by the Rev. C. Green from the
Forest-bed in the neighbourhood of Bacton, Ostend, etc., and briefly
described by him;* and subsequently, in 1858, the large and well-

1 The History, Antiquities and Geology of Bacton (Norwich, 1842).

100 Prof. T. Rupert Jones—Fossil Bivalved Entomostraca.

known series of Elephant and other vertebrate remains obtained by
the Rev. J. Layton, from the eastern coast cliffs, and from the beach
and the celebrated oyster bank lying off Happisburgh. Most of the
objects in this collection are also referable to the Forest-bed period.

The celebrated Norfolk coast “ Forest-bed” collection, made by
the Rev. John Gunn, F.G.8., now forms a part of the Norwich
Museum, where the geological collection of the late Mr. Samuel
Woodward is also preserved.

IJ.—Norrs on some Fossit Brvatvep ENTomostTRAca.

By Prof. T. Rupert Jones, F.R.S., F.G.S.
(PLATE III.)

Introduction.—Notes and references accumulating for some years
have induced me to offer some remarks on a new fossil Estheria,
and on some already known, of Carboniferous, of Permian, and of
Triassic age; also a description of some fossil Ostracoda from the
Tronstone of Shotover, near Oxford, involving remarks on all the
known Wealden species ; and lastly notes on some species found in
the Purbeck strata of the Subwealden Boring, near Battle, in
Sussex.

The specimens shown in Plate III. are illustrated under favour of
a Grant from the Royal Society for the purpose of figuring the fossil
Bivalved Entomostraca.

I. An Estrusria from the Karoo Formation, near Cradock, Cape
Colony. South Africa.

Estuerta Grevit, sp. nov. Plate III. Fig. 1.

Valves almost elliptical, except that the dorsal is less convex than
the ventral edge, and the dorsal angles are strongly pronounced.
The antero-dorsal angle points forward, and is rather low down.
The umbo is just within the anterior third of the valve. Of the
numerous concentric ridges, those nearest the ventral margin are
small and close-set; about twelve larger ridges, wide-apart, mark
the middle and more convex surface of the valves. No sculptured
or pitted ornamentation is observable. Radiating wrinkles of. the
shell, under pressure, as shown in the drawing, are not un-
common. Length +4 inch; height ~ inch. Fig. 1 shows a right
valve; magnified twelve diameters.

Numerous more or less flattened valves occur on the bed-planes
of a hard dark-grey shale, from the Karoo Formation near Cradock,
in South Africa. The specimens were found by the late Dr.
George Grey, when “excavating the shales to examine if they
would yield roofing material”; see Quart. Journ. Geol. Soc. vol.
xxvii. (1871), pp. 49 and 50. Specimens are in the Geological
Society’s Museum and my own Collection.

These little fossils! are interesting as giving some support to the

1 Estheria and its congener the Limnadia received much elucidation at the hands

of Prof. E. Grube, of Breslau, in his memoir “ Ueber die Gattungen Estheria und
Limnadia,”’ etc., in the Archiv fur Naturgeschichte, Jahrgang xxxi. 1865.

GEOL.MAG.1878. New SERIES. DECADE JI.VOL.V. PL. III.

Subiweulden boring.

EU Newtor det. CS ae WWest & Co. vamp.

—

Fossil Entomostraca.

Prof. T. Rupert Jones—Fossil Bivalved Entomostraca. 101

late Mr. A. G. Bain’s hypothesis of the Karoo Formation having
had a lacustrine origin, or, at least, having been partly formed in
fresh or brackish waters. Besides some obscure casts of small
Bivalves, Mr. D. Sharpe’s Iridine (Trans. Geol. Soe. ser. 2, vol. vii.
p- 188, and p. 277) are the only known shells from the Karoo beds.
For remarks on the geological characters of this formation, which is
either of latest Paleozoic (Permian) or earliest Mesozoic (Triassic)
age, see Quart. Journ. Geol. Soc. vol. xxiii. p. 277; and vol. xxxi.
p- 529, ete.

The form most nearly approaching Hstheria Greyii in outline is
E. rimosa, Goldenberg, Fauna Sarzpont. foss., Heft ii. 1877, p. 44,
pl. 2, fig. 16-18, from the Carboniferous beds of Saarbruck.

II. Carponrrerous EstHERiZ.
1. Estheria Dawsoni, Jones. Plate III. Fig. 2.

Tn the Gron. Mac. Vol. VII. 1870, p. 220, Pl. IX. Fig. 15, we~
gave a drawing and brief description of a Nova-Scotian specimen of
Estheria Dawsoni,! already noted and roughly figured by Dr. Dawson,
F.R.S., in his Acadian Geology, 1868, p. 256, fig. 78d.

Thanks to Mr. Robert Etheridge, junior, F.G.S., we have now
seen better specimens, though still only casts, of this species from
Scotland.? These, collected by the Geological Surveyors of Scotland,
and marked “B 1374 EH” in the Museum at Edinburgh, are single
and double valves, more or less flattened, scattered on the bed-planes
of purplish, fine-grained, micaceous shale, in the Lowest Carboni-
ferous series, east of Belhaven Bay, near Dunbar.

These Scotch specimens of EZ. Dawsoni give more perfect outlines
than those previously figured. The subquadrangular shape, wide
ridges (11 or 12), short anterior and long posterior moieties of the
valves, and the sharp postero-dorsal angle, making the posterior
margins somewhat sigmoidal, are characters in this species. No ~
ornamentation is seen either on the casts or the impressions. Fig.
2a, right valve; Fig. 26, left valve; internal casts. Magnified 10
diameters.

2. My friend, E. W. Binney, F.R.S., has communicated some
specimens of Estheria tenella from Ciudad Real, Spain. In the
Neues Jahrbuch fiir Min., etc., 1864, p. 656, E. tenella is quoted
from Saarbriicken by Dr. E. Weiss ; and in the vol. for 1869, p. 61,
Geinitz mentions it as having been found in shale at Kargalinsk,
Russia. He refers these and the Saarbriicken specimens to the Lower
Dyadic (Permian) series.

3. Goldenberg, in his “Fauna Sareepontanze fossilis,”* part 2,
1877, plate 2, figs. 9-18, illustrates Estheria tenella (Jordan), figs.
9-11; E. limbata, Gold., figs. 12-15; and EH. rimosa, Gold., figs.
16-18; together with some Leaie, etc.

23

1 Estheria Adamsii and E. Peachii were figured and described on the same occa-
sion, Joc. cit. Pl. IX. Figs. 1 and 17. E. punetatella had been already added to the
list of Carboniferous Estheri@, in the Trans. Geol. Soc. Glasgow, 1865, pl. i. fig. 3.

2 Grou. Mae. Series II. Vol. III. p. 576.

3 “Die fossilen Thiere aus der Steinkohlenformation von Saarbriicken,”’ Heft ii.

102. Prof. T. Rupert Jones—Fossil Bivalved Entomostraca.

III. Somz Triassic anp oTHER HsrHEriZ.

§ 1. New English locality for Estheria minuta (Alberti).

Some fine specimens have been obtained by Mr. T. J. Slatter, of
Redditch, Worcestershire, in a purplish micaceous clay of the Upper
Keuper Sandstone, and in the Lower Keuper Sandstone (Water-
stones), near that place. For a general section of the New Red
Sandstone of the district, see “Monograph of the Fossil Estheriz,”
Pal. Soc., 1862, pp. 62, 63.

§ 2. Notices of H. minuta and some other Estherie.

Estheria minuta has been frequently referred to by the geologists
of Germany since 1862, sometimes with new localities. In Alberti’s
“ Ueberblick tiber die Trias,” etc., 1864, it is accepted as a Crus-
tacean, and correlated with Posidonomya Albertii, Voltz, and P.
Germari, Beyrich, Zeitsch. deutsch. geol. Ges., vol. ix. 1857,
‘p. 877); also doubtfully with P. Wengensis (from Diirrenberg),
Giebel, Palzeontol. Untersuch. (not P. Wengensis of Wissmann and
Minster, Beitrage, etc., Heft 4, 1841, St. Cassian, p. 23. pl. 16,
fig. 12, which is much larger). Posidonomya nodocostata, Giebel,
Pal. Unters., pl. 2, fig. 7, is mentioned by Alberti as being prob-
ably an Estheria. Alberti’s work is briefly noticed in the Guot.
Mae. Vol. I. p. 167.

In the Neues Jahrbuch for 1864, p. 646, etc., Giimbel and Geinitz
noticed some Permian (Dyadic) fossils from Thuringia, and among
them a new LEstheria,—E. rugosa, Giimbel. See Guo. Mac.
Vol. II. p. 205.

Giimbel mentions Estheria minuta as a leading fossil of the
Variegated and the Grey Keuper, in his work on the Bavarian Trias,
“Die geognostische Verhiltnisse des frinkischen Triasgebiets,”
1865, pp. 58, 55, etc. So also does Frid. Sandberger in his
‘‘ Beobachtungen in der Wirzburger Trias,” 1865, Wurzb. naturw.
Zeitsch. vol. v. p. 221, ete.

In the Trias of the Taub Valley, Ph. Platz has found EH. minuta
in a dolomite, associated with a bone-bed, in the Lettenkohle series ;
N. Jahrb. 1869, p. 585.

E. minuta, var. Brodieana, is noticed by Fred. Romer as occurring
in the Keuper at Paulsdorf in Upper Silesia; Zeitsch. d. geol. Ges.
vol. xv. 1863, p. 702, ete., and in his ‘Geologie von Obernschlesien,”
1870, p. 176, pl. 15, figs. 10 and 11; also previously in the Zeitsch.
geol. Ges. vol. xv. (1863), p. 702, ete.

Frid. Sandberger, in the Verhandlungen d. k. k. geol. Reich-
sanstalt, Jahrg. 1871, in his remarks on “‘Die Estherien-Bank des
Keuper in Siidfrankreich (Département Gard),” p. 225, notes both
E. minute and EL. lawitexta, Sandb., which is regarded as a variety of
the E. minuta so abundant in the Lettenkohle.

E. Mangaliensis, Jones, is described by Geinitz as having been
found in a bituminous shale (Brandschiefer), of Rhatic age, from
San Lorenzo, Province of Mendoza, South America. See ‘Palzonto-
graph.,” Supplem. iii. Beitrige zur Geologie und Palzontologie der
Argentinischen Republik; i. Paleont. Theil, ii. Abtheil. Cassel,
4to. 1876, p. 3, pl. 1. figs. 1-6.

Prof. T. Rupert Jones—Fossil Bivalved Entomostraca. 103

IV. Fossin Ostracopa From SHOTOVER, NEAR OXFORD.

§ 1. Locality.—Visiting the old stone pits of Shotover Common,
March 16, 1874, in company with some students and Mr. H. Caudell,
the late Professor Phillips’ able assistant, and still attached to the
Geological Department of the Oxford University Museum, the
writer was present when Mr. Caudell picked up some fossiliferous
pieces of the ironstone. One fragment of sandstone exhibits on its
bed-plane the casts of a small Unio (U. subtruncatus ?), of a small
Cyrena (C. media ?), and of numerous Ostracods; anda fragment of
ironstone (from a crack in sandstone) bears numerous casts and
impressions of small crushed Paludine (P. Sussexiensis ?), together
with a few Fish-bones. These specimens are from the “Ironsands”
just within the field-gate, near the “h’” on the Geological Survey
Map, on the Common, about 3 miles east of Oxford. They will be
deposited in the University Museum.

The occurrence of so-called ‘‘Cyprides” in these Jronsands of
Shotover and neighbourhood had been often spoken of, but was still
doubtful ; see Prof. Phillips’s “Geology of Oxford,” 1871, p. 412.
Cavities left by the removal of the oolitic grains so common in the
Ironstone look like the impression of these little fossils; and the
partly exposed convex casts of the whorls of small Paludine often
resemble their subovate valves. In the piece of very fine-grained,
ferruginous, and micaceous sandstone containing the internal cast of
a Unio and impressions of a small Cyrena (?), ornamented with
delicate concentric ridges, numerous casts and impressions of different
kinds of Bivalved Entomostraca are plainly visible.

It is not easy, however, to master the details of form and orna-
ment of all the little Cypridiform Hntomostraca present; inner
moulds and exterior casts, more or less imperfect, being bad
material to work upon, chiefly on account of the imperfection of the
outlines of the imbedded specimens.

There seem to be five distinct recognizable forms, shown in the
accompanying Plate by Figs. 3-11.

Besides the difficulty of defining outlines and other features, we
cannot easily assign specific names to these forms, because we are
not yet well acquainted with the limits of variation among the
several Cypridiform species found in the Purbeck and Wealden
formations.

§ 2. List of the Ostracodous Entomostraca known in the Purbeck-
Wealden Formation.

The recorded species of Ostracoda known in the Purbeck- Wealden
deposits are—

1.—Cypris faba, Sowerby (not Desmarest), “Mineral Conchology,”
tab. eccclxxxv., 1824, p. 136-8; and mentioned also in the descrip-
tion of tab. xxxi., p. 78, as occurring in the Petworth Marble. This
was afterwards named Cypris Valdensis by Fitton and Sowerby.

11.—l. Cypris Valdensis, Fitton. Trans. Geol. Soc., ser. 2, 1837,
vol. iv. pp. 177, 205, 228, 229, 259, 260, 297, 344, and 352, pl. 21,

ao
>

104 Prof. T. Rupert Jones—Fossil Bivalved Entomostraca.

In the Weald Clay of Kent, Sussex, Surrey, I. of Wight, and Dorset.

In the Hastings Sand of Kent, Sussex, and Isle of Wight.

In the Purbeck beds of South Wilts and Bucks.’

2. OCypris tuberculata, Sow. Ibid. pp. 177, 205, 228, 345, and
302, pl. 21, figs. 2a, b, ¢.

In the Weald Clay, near Hythe, Kent; near Atherfield and
Cowleaze Chine, Isle of Wight; and at Punfield, Dorset.

3. Cypris spinigera, Sow. Ibid. pp. 229, 345, 352, pl. 21, fig. 3.

In the Weald Clay of Sandown Bay and Atherfield, Isle of Wight.
Doubtfully in the Purbeck Beds of Portland, ete.

4. Cypris granulosa, Sow. Ibid. pp. 177, 260, 345, pl. 21, fig. 4

In the Hastings Sand, Sussex (‘'Tilgate Forest,’ Mantell).

In the Purbeck Beds of South Wilts.

111.—Sowerby’s figures, referred to above, have been copied again
and again, in books on geology, by Lyell, Mantell, and others. In
Lyell’s ‘Elements of Geology,” 1838, p. 348, figs. 184-187, wood-
cuts are given of Cypris spinigera, C. Valdensis, and C. tuberculata,
after Sowerby’s engravings.

In his “Wonders of Geology,” 3rd edit. 1838, Mantell had a
woodcut of Cypris granulosa; and in the 7th edit. he gave figures
of C. spinigera, granulosa, and Valdensis. In his “Medals of
Creation,” 1844, he reproduced C. Valdensis and C. granulosa, to-
gether with C. tuberculata, Sow., which he divided into C. Fittoni
(namely, fig. 2a of Sowerby’s plate) and C. tuberculata proper
(=fig. 2b, c). See also “Medals,” 2nd edit., 1854, vol. il. p. 527,
Lign. 174, f. 2 and 3.

1v.—F rom the “‘ Wealden” beds of Hanover, which, however, are
related to the Purbeck rather than to the higher series, Fr. A. Romer
described and figured some Bivalved HEntomostraca in his “ Die
Versteinerungen des norddeutschen Oolithen-Gebirges: ein Nachtrag.”
4to. Hanover, 1839. Thus:

p. 52. a Cypris Valdensis, Fitton, pl. 20, fig. 20a, 6.
. C. oblonga, B., fig. 21.
5 OL striatopunctata, R., fig. 22a, b.
. C. tuberculata, Fitton, fie. 23.
. C. granulosa, Fitton, fic. 24. This differs from the C. granulosa of Sow.
and Fitton in being one of the ovate (not oblong) forms, and in having
a beak and notch.
v.—Dr. W. Dunker, in his “Monographie der norddeutschen
Wealdenbildung,” 4to. Brunswick, 1846, gave a fuller account of
the Hanoverian Entomostraca. Thus:
p.59.—1. Cypris Valdensis, Sow., pl. 18, fig. 29a, 6.
2. C. levigata, Dunker, fig. 25.
p- 60.—3. C. oblonga, Romer, fig. 24 and fig. 26a, db.
4. C. striatopunctata, Rom., fig. 32.
5. C. granulosa, Sow., fig. 31a, b.
6. C. tuberculata (?) Sow., fig. 30a, 6. This differs from Sowerby’s C.
tuberculata in being ovate and notched.
p-61.—7. @. rostrata, Dunker, fig. 27.
8. C. pinneformis, Dunker, fig. 28.

! Hampshire is included in the ‘“ Hastings Sand” Column, and Kent, Sussex,
Hampshire, and Isle of Wight in the ‘‘ Purbeck”? Column of the Table, at page 352,
evidently from inadvertence.

ue Gk

Prof. T. Rupert Jones—Fossil Bivalved Entomostraca. 105

vi.—In the British Association Report for 1850, Transact.
Sections, pp. 79-81, Prof. Edward Forbes defined several species of
‘‘ Cyprides” as characteristic of the several divisions of the Purbeck
beds of Dorset. He did not publish figures of these forms; but
from his diagrams, used at the Museum of Practical Geology, Sir C.
Lyell had reduced figures drawn for his “ Manual of Elementary
Geology,” 8rd edition, 1851, p. 231. In the sixth edition of his
“ Hlements of Geology,” 1865, they are thus given :-—

p- 878, fig. 368, a. Cypris gibbosa, BE. Forbes. [Near C. spinigera, Sow. ]
b. — tuberculata, BE. Forbes. [Near C. tuberculata, Sow.]
leguminella, Ki. Forbes.

¢.
These belong to the “ Upper Purbecks.”

p- 878, fig. 371, a. Cypris striatopunctata, E. Forbes. [? Fr. A. Romer. ]
b. fasciculata, K. Forbes.
e. granulata, E. Forbes. [? C. granulosa, Dunker. ]

These belong to the “ Middle Purbecks.”

p- 387, fig. 375, a. Cypris Purbeckensis, EK. Forbes.
b. — punctata, K. Forbes.

21

Belonging to the “‘ Lower Purbecks.
In the Mém. Soc. phys. Hist. nat. Généve, vol. xvii. part 1,
1865, MM. Loriol and Jaccard, in their “ Htude géol.. ete., Villiers-
le-Lac,” etc., notice an Ostracod as Cypris Purbeckensis, Forbes, p.
81, pl. 2, figs. 1—3; but it is difficult of determination on the small
figure given.
vit.—By way of determining the specific identities or differences
of the above-quoted fossil Entomostraca, we may take the leading
characters of shape, and, especially the antero-ventral notch, and
group the named forms accordingly. Thus—
1. Ovate-oblong, with strong notch (common
form ; Sowerby’s figured specimen).
2. Oblong, with a slight notch (Fitton’s
figured specimen).
— tuberculata, Sow. Oblong, without a notch.

— granulosa, Sow. Oblong, without a notch.
— spinigera, Sow. Oblong, with a slight notch.

C. Valdensis, Fitton. Ovate, with a strong notch.

— oblonga, R. Ovate (with a notch, according to Dunker).
Remer’s ) — striatopunctata, R. Ovate (with a notch, according to Dunker).
species.— — tuberculata, Fitton. Oblong, without a notch.

C. Valdensis, Fitton.
Sowerby’s
spectes.—

— granulosa, Fitton. Oblong, without a notch. (Without a notch
according to Dunker.)

1 In the “Catalogue of the Collection of Fossils in the Museum of Practical
Geology,’ 1865, p. 254, the following are enumerated :—
Cypridea fasciculata,
— punctata,
— Valdensis, Middle Purbeck.
Cypris striatopunctata,

— Purbeckensis,
Cypridea tuberculata !
— Valdensis, Upper Purbeck.

Some of these names have evidently been adopted from Forbes.

106 Prof. T. Rupert Jones—Fossil Bivalved Entomostraca.

CO. Valdensis, Sow. Ovate and notched.

— levigata, Dunker. Ovate and notched.

— oblonga, Romer. Elongate-ovate and notched.
Dunker’s ) — striatopunctata, Romer. Ovate and notched.
speciés.— ) — granulosa, Sow. Ovate and notched.

— ? tuberculata, Sow. Ovate and notched.

— rostrata, Dunk. Ovate and strongly notched.

— pinneformis, Dunk. Long-ovate and notched.

Forbes’s species.—None of the above-mentioned rough figures of
Forbes’s Purbeck species (page 105) show the notch in any degree ;
but, beimg drawn from various points of view, they are, of course,
not satisfactory. In the Catalogue Foss. Mus. Pract. Geol., 1865,
above quoted (page 105), C. fasciculata, punctata, Purbeckensis, and
tuberculata are referred to Cypridea ; C. striatopunctata and Purbeck-
ensis being left with Cypris.

§ 3. Remarks on the Wealden Ostracoda.—Although these Entomo-
straca (Ostracoda) have been so generally referred to Cypris, it is
very doubtful if any of them belong to that genus; in all proba-
bility, the majority belong rather “to the Cytheridee than to the
Cypride.

The classification of these kinds of Bivalved Hntomostraca runs
thus.!

OSTRACODA: PODOCOPA.
1. Cypripz. 2. DarRwINELLADm. 3. CYTHERIDE.

Cypris, Darwinella, Cythere,
ee Cytheridea,
etc.

Among the fossil Oana. iat the Purbeck-Wealden strata there
are three kinds of Carapace-valves.

A.—For the most part, the shape and structure of the valves are
such as occur more especially with Cythere and Cytheridea ; differing,
however, chiefly in the hingement, which wants the knurlings. of the
latter and the distinct teeth of the former. In this respect they
agree best with the forms of “ Cytherideis” figured in Monogr.
Tert. Entom., 1856, pl. 2, figs. 2, 3; but that is not a well-deter-
mined genus.

B.—Some of the Wealden Ostracoda are characterized by having
an antero-ventral notch, more or less pronounced, especially in the
more ovate forms of C. Valdensis; see Monogr. Fossil Hstheriz
(Pal. Soc.), 1862, Appendix, p. 127, pl. 5, figs. 26 and 28. The
presence of this feature induced M. J. Bosquet,’ of Maestricht, to
suggest that such species should be referred toa separate genus
— Cypridea.

As a matter of convenience, it will be well to use this name,
although as yet we do not understand the physiological value of the
feature in question, which is certainly very variable in development.
Ii may be concerned with the play of the lower antenne ; but it is

1 Brady, Crosskey, and Robertson’s Monogr. Brit. Post-Tertiary Entom., Pal.
Soc. 1874, p. 110, etc.

pas Description des Entomostraces fossiles des Terrains tertiaires de la France et
de la Belgique,” Mém. cour. Acad. Roy. Belg., vol. xxiv. 1852; page 47 of the
separate memoir.

Prof. T. Rupert Jones—Fossil Bivalved Entomostraca. 107

not accompanied by a gaping of the valves, as in Asterope and
other Cypridinads.

The characteristic feature of Cypridea is sometimes expressed
only by a very small notch under a diminutive beak, or by even
a slight indenture below and behind a thickening of the antero-
ventral angle, as in Fitton’s specimen of C. Valdensis, fig. 1, pl. 21,
Trans. Geol. Soc., 2nd ser. vol. iv. Sometimes it is obsolete, or
traceable only by a curvature of the inside edge. Sowerby’s C.
tuberculata and C. granulosa do not exhibit any notch in his figures,
nor in our examined specimens. C. granulosa is also described by
Sowerby as wanting the anterior “lobe” seen in C. Valdensis. His
fir. 3a. of C. spinigera does show a linear trace of the notch, de-
fining a marginal lobe. In a form closely related to C. spinigera,
shown in the accompanying Plate (Figs. 9 and 10), we also see such
an antero-ventral indentation. In Figs. 4, 5, 6, and 7 of our Plate,
we have several conditions of a form related to Sowerby’s C. granu-
losa, but with strong indications of notch and beak.

It is, of course, highly desirable to make as few generic divisions
as possible of these thick-shelled, oblong or ovate-oblong Ostracoda
of the Wealden and Purbeck beds. If “notched” in any degree,
they may be referred to Cypridea ; but it is often difficult to deter-
mine whether or no the notch be obsolete, reduced to a minimum, or
altogether absent. Those without any trace of the notch, such as
Sowerby’s C. tuberculata, can be referred only to Cythere at present,
unless, on the ground of their having otherwise a general re-
semblance, we venture to group them as Cypridew with an obsolete
notch.

C.—There is, however, another and distinct kind of Ostracodous
valve associated with the foregoing in the Shotover hand-specimen
of Ironstone, and in the black Cyrena-shale of Hanover. These
latter I wrongly correlated in the “‘ Monogr. Foss. Hstheriz ” (Pal.
Soc.), 1862, Appendix, pp. 122 and 123, with Cypridea Valdensis
(Sow.) and ©. oblonga (Roemer), both of which are notched and
beaked. After further consideration I am satisfied that figs. 30-34 |
in pl. 5 of the Appendix to the “‘ Monogr. Foss. Esth.” are closely
related in form and structure to the recent OCandona candida (Miller)
and its allies; except, perhaps, that fig. 81 may be a Darwinella.
They possess neither the notch nor the thick shell of the other
Purbeck-Wealden forms (Cypridea Valdensis, etc.) ; but resemble
very much some common Oyprides and Candone, and the less-known
Darwinella, in their thin, shining, oblong, and apparently hingeless
valves. Fig. 30, indeed, somewhat compressed, and drawn with the
posterior end upwards, is probably the same as one found at Shot-
over, and may be regarded as a Candona; see further on. Fig. 31
is extremely like Darwinella Stevensoni, Brady and Robertson,’ in
outline. Figs. 32-34 may be three different Cyprides or Candone,
as far as the valves indicate special features.” ‘The importance of

1 Monogr. Post-Tertiary Entom. 1874, p. 141, pl. 2, fig. 13.

2 ‘We may remark that fig. 25, on the same plate, representing Candona Kotahensis,

from the Jurassic beds of India, has almost exactly the outline of the recent
Candona lactea.

108 Prof. T. Rupert Jones—Fossil Bivalved Entomostraca.

giving full credit to differences in valve-structure among these fossil
Ostracods, whose recent representatives have their specific characters
so largely marked in their limbs and soft parts, must always be borne
in mind.

§ 4. Description of the species from Shotover.

1. Canpona Purniipsiana, sp. nov. Plate III. Fig. 8. Internal
cast of a left valve; magnified 20 diameters.

One relatively large, brown, shining, internal cast on the piece of
fossiliferous sandstone from the Shotover Ironsand (see above, p. 108)
indicates a right valve very similar to that of Candona candida '
(Miller); subreniform or ovate-trigonal; thick and high in the
posterior third; sinuate on the ventral, and obliquely convex on the
dorsal edge ; semicircular in front, and sloping boldly and obliquely,
with a gentle curve, behind. The cast shows by slight marginal
ledges, anterior and posterior, that the edge of the valve was
widened by an inner free lamina, as in Candona candida, from
which, indeed, this species is distinguishable chiefly by its greater
height and blunter posterior margin.

It differs in form from the somewhat similar marine Cytherideis
nobilis, Brady,? in its more tapering anterior third, less sinuous
ventral margin, and far more oblique posterior outline.

Associating the name of the late Prof. John Phillips with this
rare species, I dedicate it to the memory of that eminent geologist,
one of the most earnest workers in the Shotover formation. Not
long before his death he was much gratified by the information that
real Cypride had been found in these Ironstones.

2. CYPRIDEA VERRUCOSA, et var. CRASSA, Sp. et var. nov. Plate IIT.
Figs. 4-7.

Valves oblong ; convexity greatest at the posterior third. Surface
pitted or coarsely reticulate, and bearing numerous tubercles, more
particularly on the anterior and posterior thirds. Front edge of
each valve semicircular; upper and lower edges nearly parallel,
except in the advanced stage (or variety crassa, Fig. 4),in which the
- dorsal border is convex. Posterior margin rounded with elliptical
curvature. Antero-ventral region either marked with a slight in-
denture and notch (Figs. 6 and 7), or strongly beaked (Fig.5). In
Fig. 4 (an imperfect and partly obscured individual), the two most
forward tubercles to the left of the reader really belong to the
massive lobe or beak, better seen in other fragments, and clearly
but less strongly developed in Fig. 5. The gradation between these
specimens seems to he complete.

Figs. 5, 6, and 7 approach very near to Cythere (?) granulosa (Sow.) ;
but they show the special indenture or notch. Fig. 4 somewhat
resembles Cythere (?) tuberculata (Sow.), but differs notably in shape
and arrangement of tubercles.

1 T. Rupert Jones, Monogr. Tert. Entom., Pal. Soc., 1856, p. 19, pl. 1, figs.
5 and 8: G. 8. Brady, Monogr. Rec. Brit. Entom., Trans. Linn. Soc., 1868,
p- 383, pl. 26, figs. 1-9: Brady, Crosskey, and Robertson, Monogr. Brit. Post- Tert.

Entom., Pal. Soc. 1874, p. 135, pl. 2, figs. 29, 30.
2 Trans. Zool, Soc. vol. ¥. (1868), p- 368, pl. 58, fig. 9.

Prof. T. Rupert Jones—Fossil Bivalved Entomostraca. 109

Fig. 4. Partly imbedded and partly broken left valve.

Fig. 5. Shows the shell (broken) of a left valve.

Fig. 6. Shows a restored right valve from a hollow impression of
exterior.

Fig. 7a. Shows the shell of a left valve, imperfect at the notch.

Fig. 7b. Shows the dorsal aspect of the same specimen.

These are all magnified 20 diameters.

Cypridea verrucosa has some resemblance to Lyell’s figure of
Cypris tuberculata, Forbes. But the latter shows no notch; and, if
it be distinct from Sowerby’s C. tuberculata, its name is pre-engaged.

3. CYPRIDEA BISPINOSA, sp. nov. Plate III. Figs. 9 and 10.

Valves ovate-oblong, with indenture and notch, and with a coarsely
pitted surface, bearing two sharp tubercles on the posterior third.
This has a near relation to Cypridea spinigera (Sow.), but is more
oblong in shape, having a straighter ventral edge; and instead of
one central tubercle, it possesses two spinous processes, one on the
postero-dorsal third of the valve, and one below and rather behind
the middle of the valve.

Fig. 9 is restored (reversed) from a hollow impression of the
exterior of a right valve. Fig. 10 is an internal cast of a left valve,
showing traces of the muscle-spot. Both are magnified 20 diameters.

4, CypripEa Vaupensis (Fitton). Plate III. Fig. 8, oblong var.
of CO. Valdensis (?) ; internal cast, showing muscle-spot. Fig. 11,
outline of one of the common ovate and notched forms of C. Valdensis.
Maenified 20 diameters.

The most common species found in the Wealden is that which
Sowerby at first referred to Desmarest’s Cypris faba, see Min. Conch.,
pl. ceeelxxxv. (1824), and which Fitton, with Sowerby, subsequently
named Cypris Valdensis. From Sowerby’s figure, and from the many
particular Cypridiferous strata to which Fitton alludes in his memoir
“On the Strata below the Chalk,” etc., we know that the specially
abundant form to which he refers has ovate-oblong valves, with a
decided antero-ventral beak and notch. The form has been recog-
nized also by Dunker and others as the C. Valdensis. The figure,
however, given by Sowerby and Fitton in the above-mentioned
Memoir, Trans. Geol. Soc., 2nd ser. vol. iv. pl. 21, fig. 1, is unfortu-
nately not that of the common form, but of an oblong variety (if not
species), with the notch and beak indistinct or nearly obsolete.

The ovate and strongly beaked form of C. Valdensis is present
(though rare) in the Shotover sandstone (Fig. 11). It is narrower
than the individual drawn in the “ Monogr. Foss. Estheriz,” Pal.
Soc., pl. 5, fig. 28; and approaches closely Dunker’s figure of this
Species.

Among the badly preserved casts of valves in the iron-sandstone,
is one of an oblong carapace (Fig. 8), possibly of the squarer form of
C. Valdensis, since its surface shows no trace of tubercles. This is
of considerable interest as showing marks of the muscle-spot. In
this valve there were six small internal pits; three parallel in a
vertical row, with one oblique mark in front and two oblique
behind.

110 Prof. T. Rupert Jones—Fossil Bivalved Entomostraca.

V. OstRAcoDA FROM THE SUBWEALDEN Borine 1n Sussex.

1. Cypripma Vatpensts (Fitton). Plate III. Figs. 13-15.

In a bluish limestone of the Purbeck series in the boring at Lime-
kiln Wood, Netherfield, near Battle, Sussex, from the depth of 85ft.,
we have numerous specimens of single and double valves of Ostra-
coda, mostly Cypridea Valdensis of the common ovate form, 7.¢.
tapering behind with a postero-dorsal slope. They are slightly
indented at the posterior angle; and all have the antero-ventral
notch. In all these particulars they differ from the oblong and
slightly notched individual figured by Fitton. Some are shorter
than others, and relatively higher; more like a peach-stone in out-
line; and are such as is represented in fig. 28, pl. 5, Appendix,
‘‘Monog. Foss. Estherie.” Analogous forms, together with still
squarer valves, occur in the hard thin shales of the Weald Clay at
Peasemarsh, near Guildford, Surrey; but the notch is obsolete, or
even absent, in these. These, with the specimen figured in Fitton’s
pl. 21, fig. 1, may be termed Cypridea Austent.

2. Cypridea granulosa (Dunker). [Not Cythere? granulosa,
(Sow.)] Plate III. Fig. 16; magnified 20 diameters.

This elongate-ovate, notched, and somewhat tuberculate Cypridea,
answers well to Dunker’s fig. 31a, b, pl. 18, Cypris granulosa, p. 60,
of his “Monogr. Nordd. Weald.” 1846. It is rarer in the Nettlefield
Limestone than its associates.

3. Candona? vel Cythere? Plate III. Fig. 12 a, 6; side and edge
views of a carapace; magnified 20 diameters.

This small, neat, smooth carapace, elliptic-oblong in outline, with
a straight dorsal (?) edge, also occurs in the Subwealden limestone
at 85 feet. It is impossible to define its genus at present.

4. In specimens from the Subwealden Boring, with which I was
favoured, in 1872-3, by Mr. H. Willett, F.G.S., and his colleagues
in the enterprise, I found as follows :—

Depth 84 feet.—Greenish limestone, having smooth fracture, with a greyish granular
Cypridiferous limestone in cracks of the denser portion. Cypris? (one) sub-
trigonal and very delicately striolate, in the granular portion. Candone (?)
suboblong and smooth, on a bed-face of the greenish portion.

Depth 85 feet.—Greenish-grey earthy Cypridiferous limestone, rich with Chara also.

Cypridea Valdensis, C. granulosa, etc. (See above.)
Chara seed-vessels and stems.

Depth 92 feet.—Grey earthy Cypridiferous limestone, consisting of layers of Cyprids
with intercalated thin seams of hard shale ; and with granular (Cypridiferous)
limestone filling cracks.

Cythere?—oblong (new), and another ?
Minute black vegetable stems.

Depth 96 feet.—Greenish-grey Cypridiferous limestone, consisting of alternate
layers of Cyprids and shale.

Cythere? oblong. (Like that at 92 feet.)

Depth 103 feet.—Dark-grey earthy limestone, with minute, black concretionary (?)
and vegetable (carbonized) specks.

Depth 136 feet.—Grey, hard, Cypridiferous, banded limestone, like those from
92 feet and 96 feet, but harder, and with its structure more obscure. Holes
and cracks in it have been filled with a more granular limestone.

5.—In a black shale from Archer Wood, near Battle, also com-
municated by Mr. Willett, F.G.S., were numerous specimens of the
ovate Cypridea Valdensis, but not well preserved.

J. A. Birds—Geology of the Channel Islands. al

I1I.—Gurotoey or THE CHANNEL IsLANDS.
By J. A. Brrps, B.A., F.G.S.
(Continued from p. 86.)
Part II.—Post-Pliocene Geology.

ROM the sandstone (7), which Professor Ansted asserts, though
without giving his reasons, to be ‘“‘no doubt modern,” and to
have been “deposited before” [just before?] “or during the last
great elevation,” down to the superficial clays and sands, there is
not a scrap of any other Secondary or Tertiary rock in situ to be
found on any of these islands. We leap at once from this sandstone
to clays and sands of Post-Tertiary date. Mr. Duncan, in his
History of Guernsey (edit. 1841, p. 513), says that “ flint and chert
nodules, containing impressions of shells, etc., are frequently dis-
covered beneath the soil in places which preclude the probable
transport by the hand of man.”

“This,” he adds, “is especially the case on the denuded summit
of the gneiss of the South of Guernsey.” I conclude he means
in the brick-clays and sands covering the §.E. corner of the
island. I have myself traced these clays, etc., from near the
Doyle Column on Jerbourg Point, round by St. Martin’s and
St. Andrew’s Churches, to the Foulon Cemetery, and the Amherst
Road above St. John’s Church, in St. Peter’s Town; and I found
two or three small specimens of chalk flints in the clay associated
with pebbles and fragments of gneiss, granital, quartz, and other
rocks of the neighbourhood. The island of Sark, in the same
manner, is covered at various points with a coating of clay con-
taining stones, generally derived from the underlying rocks; but, at
the old mine-heaps in Little Sark, I found, beside these, a fragment
of amygdaloid, and another almost perfectly hexagonal fragment of
basalt, not, so far as I know, derived from any of these islands.
Alderney, again, is said to contain almost inexhaustible supplies of
brick-clay, which has probably a similar derivation.

Jersey, also, is covered in many places with brick-clay and sand,
especially around St. Helier’s; but no chalk flints have been found
in these deposits. Upon the shores, however, of all the islands,
without exception, chalk flints occur, and in some places very
abundantly. Dr. MacCulloch in 1811 says that he “picked up flints
upon the beach at Alderney,” and Professor Ansted calls attention to
a singular profusion of chalk flints often of large size in Port-Saie,
on the N.EH. of Jersey; and also on the beach at Grouville Bay ;
and he appears to think, from their being found chiefly in the
neighbourhood of the newer conglomerate (h), that they may
possibly have been derived from it. They have not, however, he
admits, ever been seen 7n situ in the conglomerate itself. I can add
that the flints are to be found, though not in equal abundance, in St.
Clement’s Bay and the Gréve d’Azette on the south, and in Bouley
Bay on the north—in fact, on all the shores of the eastern half of
Jersey. ‘They are wanting, Professor Ansted says, on the western

112 J. A, Birds—Geology of the Channel Islands.

side. In Guernsey, however, they are plentiful in all the bays on
the west and north-west—in Rocquaine—but especially in Vazon
and Cobo Bays, and Grand Havre ; while they are also to be found
in Bellegréve Bay on the east; and even, though sparingly, in
Moulin Huet and Saint’s Bay on the south. They occur too in
Icart Bay and at Epercherie in Sark.

Now what is the origin of all these coverings of clay and sand,
and of the chalk flints? It is very improbable that any of it is true
Boulder-clay, belonging to the first continental period. But few
boulders, and no “scratched” blocks, or stones, have been observed
in it. Nor are there any of the other usual glacial signs to be seen
upon the islands. Nor again, Prof. Ansted says, ‘“‘is there any gravel
consisting of transported pebbles of foreign material” to be found
there. Much of the clay and sand may have been derived from the
decomposition of the underlying porphyries and syenites. Much,
however—especially that in the 8.E. of Guernsey—has the appear-
ance of a genuine drift; and, unless a more probable origin can be
suggested, I should be inclined to refer it to the intraglacial period
of submergence ; to which also I would refer the presence of the
chalk flints upon the shore.

The question, however, arises: how could this be if, as exhibited
in the “Map of the supposed submergence of the British Isles and
N.W. of Europe,”? the South of England and N.W. of France, ete.,
had been dry land? We might indeed suppose that ice coming from
the north, and loaded with clay and flints, etc., occasionally made
its way through the Straits of Dover, or up the Channel, and de-
posited its freight around the Channel Islands; and this would
account for the flints now found on the shores, but it would not
account for the clays containing flints, as in the 8.H. of Guernsey,
200 or 800 feet above the sea.

Since 1846, however, when E. Forbes first expressed the opinion
that “the South of England and Ireland were in all probability
unsubmerged during the Glacial epoch,’”? a certain amount of evi-
dence has been gathering which seems to show that this opinion
must be modified, and that at all events the greater portion of the
South of England, as well as perhaps the N.W. of France and
Belgium, were submerged in the interval between the two conti-
nental periods.

For example, in 1853, Mr. Trimmer, the discoverer of the drift
on Moel Tryfaen, pointed out that there were three sets of gravels
south of the Thames, viz. at Shooter’s Hill, Dartford, and Rochester,
the northern origin of which was proved by their contents.’ Among
other northern stones he found a peculiar kind of quartzose pebbles,
which had previously been traced by Dr. Buckland from their original
home in a Triassic conglomerate on Cannock Chase, down the valley
of the Avon into Worcestershire; and thence, over depressions in
the Cotteswold Hills, to Oxford, and so down the valley of the

? Antiquity of Man, p. 276.

2 Mem. Geol. Surv. vol. i. p. 364. }

3 Quart. Journ. Geol. Soc. vol. ix. 1858, part iii. of Mr. Trimmer’s paper.

J. A. Birds—Geology of the Channel Islands. 113

Thames as far as Hyde Park.! These gravels Mr. Trimmer regards
as contemporaneous with the rolled gravel and upper erratics of the
counties north of the Thames, 7.e. of Middle Glacial age. '

Mr. Trimmer again, from the presence of Boulder-clay at Youghal
in the South of Ireland, and from grooved and scratched blocks in
the south of Co. Kerry, infers that “the South of Ireland was
subject to glacio-marine operations ;” and he adds that “the boun-
daries which have been assigned to the Boreal Ocean in order to
explain the relations of the existing fauna and flora of the British
Isles? will require considerable modification,” that is, as I understand
him, an extension further south.

Again, the same writer quotes from Rutter’s “Delineation of
Somersetshire ” (1829) to the effect that “a bed of rolled gravel,
associated with the bones of diluvial quadrupeds, was then to be seen
at the mouth of the Avon;” and further, that ridges of sand and
shingle ‘‘are occasionally found in Somersetshire rising up through
alluvial deposits ;” e.g. at Yatton, where a section of these was to
be seen in the railway cutting.*? Lastly, Mr. Trimmer has described
a bed of gravel on the summit of Clevedon Down, 300 feet above
the sea, which he considers to be of Post-Pliocene age. The late
Prof. Beete Jukes was, perhaps, deceived as to the existence of
glacial markings in the valley of the Exe;* but Mr. G. Maw has
pointed out a deposit of what he believes to be Boulder-clay at
Fremington, near Barnstaple,’ and he is supported in this opinion
by the Rev. W. 8. Symonds, who believes that “it may be a glacial
Till like that of Bovey Tracey.”® This Till itself again is another
argument in favour of the submergence of a considerable portion of
the South of England. At Petrockstow, in the centre of Devon-
shire, there is said to be an isolated bed of Dartmoor gravel, which
has travelled twelve miles from its source. - This, too. is identified
with the glacial clay of Bovey Tracey. Chalk flints, I believe, are
to be found more or fewer on all the coasts of Cornwall and Devon-
shire. J have myself found them along the coast of North Devon as
well as on Paignton Sands, near Torquay, and under Petit Tor, St.
Mary Church, in the south. At Newton Bushel, a few miles north
of Torquay, there is a very remarkable deposit of flint-gravel, 100
and more feet above the sea, which alone would imply the recent
submergence of this part of the country to at least that depth. These
flints, as well as some Greensand gravel on the opposite side of the
valley, are, apparently, relics of a mass which has floated from the
north. So much for the evidences of submergence, of at least a
great portion of the South of England, in the intraglacial or intra-
continental period.

What similar evidences may exist of submergence of the north and
north-west of France and Belgium I am not prepared to say. Some

1 Trans. Geol. Soc. vol. v. p. 251.

2 Mem. Geol. Surv. vol. i. plate 7.

3 Quart. Journ. Geol. Soc. vol. ix. pp. 282-286.

Grou. Mae. Vol. II. p. 473, and Geol. Quart. Journ. vol. xxiv. 1868, p. 3.

Quart. Journ. Geol. Soc. vol. xx. 1864, p. 445.
Records of the Rocks, by Rey. W. 8. Symonds, p. 278.

DECADE II.—VOL. V.—NO. III. 8

an

114 J. A. Birds—Geology of the Channel Islands.

years ago I ventured to describe, in this Macazinn, a bed of chalk
flints near Spa, in Belgium,’ which I imagined might have been
deposited by floating-ice at the epoch in question. If this was
the case, and supposing the submergence to have been uniform and
general, it must have been to a depth of 1500—2000 ft., which
would have reduced all Europe north of the Alps and Pyrenees to a
sea, with only a few mountain or hill ranges—as the Harz, the
mountains of the Black Forest, the Vosges, the hills of Central
France, and some few summits in Brittany, remaining as islands in
the midst of the waters.

This bed of chalk flints, therefore, I am unwilling to cite as evi-
dence of submergence ; although it is not necessary to assume that
the depression was either uniform or general.

But to return to the question of the clays, etc., and flints of the
Channel Islands, and the probable origin of their presence there.

Only two or three causes, it is evident, are probable or possible.
Hither (1) they are the relics—and meagre ones indeed—of a former
extension of the Chalk or some later formation containing flint-
gravel upon or near the spot; or (2) they must have been trans-
ported from a distance, and that either by oceanic currents, or by
ice: and of these two alternatives the latter is surely far the more
probable.

It is not necessary indeed, as was said above, to suppose that the
South of England was submerged so as to allow of the passage of
ice-rafts in a direct line from the north; these might still have
wandered up and down the Channel from the S.W. or N.E.,
occasionally bringing freights of chalk and flints with them. That
such ice-ships were wafted, even from the south, has long since
been inferred from the presence of erratic blocks on the coast
around Selsea Bill and Pagham, which are believed to have come
from Brittany or the Channel Islands. These blocks, indeed, are
adduced as evidence of an ancient coast-line existing there during
the intracontinental period—and therefore of the non-submergence
of the South of England. No one, however, can say how far such
a coast-line might have extended east and west; and, therefore, it is
scarcely an argument against a general submergence of the country
south of the Thames and the Bristol Channel such as I have been
advocating—in which case, it is obvious that the amount of chalk
and flints borne southwards, e.g. over Salisbury Plain, and between
it and the Mendips. would be very greatly increased. Also, if the
submergence extended to the Channel Islands, it would account for
the clays, ete., containing flints (on the summit of Guernsey), which
would not be accounted for otherwise.

The evidences of elevation of the British Isles during the first and
second continental periods, and of submergence in the intermediate
time, are clear and numerous, as regards the country north of the
estuary of the Thames and the Bristol Channel; and as yet they
are, and perhaps always will be, few and obscure to the south of
that line ; but is it reasonable to suppose such enormous movements

1 Grou. Maa. 1866, Vol. III. p. 501.

CO. J. A. Meijer—Micrasters in the English Chalk. 1108

—speaking roughly, some thousands of feet of elevation above—
2000 ft. depression below—600 ft. again elevation above the present
level, in the north; and that the south should have shared in the
first and the last of these movements, as it must have done, for
England to be united with the Continent, but that it should have
had no corresponding share in the intermediate one? Surely this is
highly improbable a@ priori. There cannot be any magic in the
line between the mouth of the Thames and the Bristol Channel
that it should present an effectual obstacle to the continuation of a
movement which must have been due to deep-seated and wide-
spread causes operating within the crust of the earth.

1V.—MIcRASTERS IN THE EnGLisH CHaLK—Two oR mMoRE SPECIES ?
By C. J. A. MrYer, F.G.S.

O the student of Cretaceous paleontology there could be suggested,
probably, no more puzzling question than that of the determina-
tion of the species of the genus Micraster. It seems not unlikely
that Professor Forbes was of this opinion when, in 1850,' he reduced
to varieties of a single species—that of Micraster cor-anguinum—no
fewer than seventeen previously supposed species, or subspecies, of
the genus. It is true that, out of compunction, perhaps, for such
wholesale slaughter, he forthwith established one new species, the
Micraster cor-bovis, and pointed out the probable existence of another
—“a small Micraster with a very elevated extremity from the Chalk
of Lyme.” This, however, seems scarcely to make up for the
absorption or obliteration of all but one of the previously described
species. And, seeing that several of these so-called varieties of
Micraster cor-anguinum are recognized as species by many conti-
nental paleontologists, it becomes an interesting subject for inquiry
whether our English Chalk does not contain more than one species
in addition to the recognized Micraster cor-anguinum and cor-bovis ?

The genus Micraster, as defined by Agassiz, appears to have met
with very general acceptance. Its stratigraphical range is brief.
Its extreme of variation, although considerable, is not great as com-
pared with that of many other genera. Whence then has arisen so
wide a difference of opinion in respect to the number and value of
its species ?

This question has not unfrequently occurred to me when seeking
some palpable distinction between specimens of Jicraster seemingly
different. The answer appears to lie in the smallness of the differ-
ence between one species or specimen and another.

It is embarrassing, certainly, to find that in a given series of
specimens one should feel compelled to recognize either several
species or variations only of a single species according to the mode
of arrangement of the specimens, and yet such appears to be practi-
cally the case. Arrange the specimens irrespectively of strati-
graphical considerations, as Forbes appears to have done, and it is
possible to obtain such a graduated series as shall apparently
obliterate all marked distinctions of length, breadth, and height.

1 Mem. Geol. Surv. decade iii.

116 CC. J. A. Meijer—Micrasters in the English Chalk.

Arrange them, as Nature has done, stratigraphically, and one cannot
but allow of certain distinctions not otherwise so readily apparent.
In the one case, however, one will have, unintentionally, grouped
together specimens in which the position of the mouth, or peristome,
will be as different as appears in the outline figures 1 and 2.

EirGaele Fie. 2.

S ].

In the other, or natural, arrangement, the position of the mouth
will be found to be almost constantly the same in specimens from
the same geological horizon, and widely different only between
those from different horizons. And it will be observed that a cor-
responding variation takes place in respect to the position of the
apical disk. In the natural arrangement of the specimens one
obtains, in fact, an almost regular gradation in the relative positions
of the mouth and apical disk (as shown in Fig. 3), and a gradation
also, more or less regular, in other minor points of difference.

edeceba

EVGamoe

“ 8 @ G @

Fre. 3.—In which the changing relative positions of the mouth and apical disk
are indicated by the lines a-a, b-6, etc.

R. Etheridge, jun.—Paleontological Notes. iy

Practically then the Micrasters of one horizon in the Chalk differ
from those in the preceding or succeeding horizon in a manner
which is suggestive rather of progressive development than of
simple variation,

But there are other less apparent, yet not less actual, differences
between the various forms or species of Micraster. One of these
consists, as has been well shown by Prof. Hébert,’ in the arrange-
ment of the granules on the petaloid portion of the dorsal ambulacra.
Another difference may be observed in the ornamentation of the
base of the test. Yet another in the number of plates impinging
on, or notched by, the anal opening, which varies apparently from
seven in the earlier species to five and sometimes four only in the
later forms, or species, in the English Chalk. Independently, there-
fore, of differences of height, length, and breadth, which vary to
some extent in the same species, and setting aside Micraster cor-bovis,
and the extreme form of M. gibbus now generally recognized as an
Epiaster, there would appear to be greater constant differences
between the Micrasters of the English Chalk than is consistent
with simple variation.

Have we then indeed but two species of Micraster in the English
Chalk? For myself I am inclined to the opinion that we have not
two species only, but several species, as many possibly as six or
seven. What these represent may possibly form the subject of a
future note. |

V.—PatzontoLocicaL Nores.

By R. Erueripes, jun., F.G.S.
(Continued from Vol. IV. N.S. p. 320.)

1. Dentatium iInGENs, de Koninck, and D. ornatum, de Kon.
(Descrip. Animaux Foss., pp. 317 and 318, t. 22, f. 2 and 3).—
The first of these species has been often recorded from Scotch
Carboniferous rocks, but, so far as I am aware, the second is new
not only to Scotland, but in British Carboniferous rocks generally.
Specimens were forwarded to Prof. L. G. de Koninck, M.D., who
was kind enough to confirm my determination. Our specimens of
both the above species show the growth strize of the shell to have
been waved, like the septa of some Orthoceratites, consequently I
presume the anterior apertures would be similar. In Prof. de
Koninck’s figures the striz are oblique, and the anterior aperture
is described as oblique. D. ingens is from the shale above the Skate-
raw Limestone (L. Carb. Limestone Group) at Hast Barns, near
Dunbar, and D. ornatum from shale above the Roscobie Limestone at
Roscobie.

Collector, Mr. James Bennie.

2. RuHYNCHONELLA or ORTHIS, n. sp.(?).—A very peculiar Carbon-
iferous Brachiopod has lately come to light; unfortunately we have
only one specimen at present, and that not quite perfect about the
hinge. The shell in question is minute, about the size of a small

1 Mem. Soc. Geol. de France, 2 ser. tom. y. pl. xxix. fig. 14-19.

118 Rh. Etheridge, jun.— Paleontological Notes.

pea, and very closely resembles in form and general characters the
Silurian Orthis biloba. We have only one valve, the ventral (?),
which is markedly bilobed, with numerous close fine longitudinal
ribs. The specimen was forwarded to Mr. T. Davidson, F.R.S.,
who, on returning it, said, “‘In outward shape, as you justly remark,
it much resembles Orthis biloba from the Silurian rocks, but you
Say your specimen is Carboniferous..... . Unfortunately the
hinge-line, or part close to the hinge, in the interior, is not well
preserved, so that it is difficult to determine whether it is an Orthis
or a Rhynchonella.... . If it were Silurian, I should almost take
it to be Orthis biloba.” It will perhaps be best to catalogue it as
Ehynchonella? sp., until the discovery of further specimens shall
enable us to arrive at a more definite conclusion.

Loc. and Horizon.—Skateraw, near Dunbar, in Lower Carbon-
iferous Limestone shale.

Collector, Mr. J. Bennie.

3. PENTREMITES, sp.—So far as I am aware, this genus has not
been recorded from the Scotch Carboniferous series. We have in
the collection of the Scotch Survey a portion of a minute ambu-
lacrum, washed amongst other small things from a sample of shale
by Mr. Bennie. The form of the ambulacrum when perfect would
be lanceolate, with a minute flexuous ambulacral groove. The
latter is crenulate on the sides, giving off short alternate lateral
grooves which communicate with sockets. From the slits or holes
in the lateral margins of the ambulacrum run in other grooves,
which lead to larger sockets than those terminating the branch
ambulacral grooves, and set alternately with the latter. The under-
surface of the ambulacrum is flattened. These features are so like
those described by the late Mr. Billings in the ambulacra of
Pentremites pyriformis (Canadian Pal. Foss. vol. ii. pt. i. p. 114),
that I think it very probable the small ambulacrum in question is
that of a Pentremite. It is quite different from that of Astrocrinites
Benniet (mihi).

Loc. and Horizon.—Carlops Quarry, Peebleshire, shale over the
Carlops Limestone, Lower Carboniferous Limestone Group.

Collector, Mr. J. Bennie.

4. SprrorBIs spinosa, de Koninck (Descrip. Anim. Foss. Terr.
Carb. Belgique, p. 58, t. G. f. 8, a-c).—This species occurs in the
Scotch Carboniferous system sparingly. I recognized a few ex-
amples in some washings obtained at Gair, Lanarkshire, a few
years ago by Mr. Pennie, from shale above the Gair Limestone (Up.
Carb. Limestone Group), and have since seen it from one or two
other localities.

5. CHonetEs pouita, M‘Coy.—Both M‘Coy (Brit. Pal. Foss. p. 457,
t. 3d, f. 80) and Davidson (Mon. Brit. Carb. Brachiopoda, p. 190,
t. 47, f. 8-11) describe and figure this species as possessing a smooth
shell. I find. however, that many examples from localities in the
neighbourhood of Edinburgh show that the shell was marked longi-
tudinally with faint, semi-effaced, flattened ribs or striz, usually
much more marked towards the front margin.

Reviews—Prof. A. von Lasaule—Aus Irland. 119

Localities and Horizon.—Shale above the No. 1 Limestone of the
Mid-Lothian Carboniferous area at Fernie-hill, Gilmerton, near
Edinburgh; Cousland and Darcey Quarries, near Dalkeith, and
numerous other localities in the Lothians and Fife.

Collector, Mr. J. Bennie. :

6. Hyatonema, sp.—As supplementary to the localities given by
the Messrs. Young for Hyalonema parallela, M‘Coy, in their in-
teresting paper on that form (Annals Nat. Hist., Nov. 1877), I can
afford the following in the East of Scotland where the ‘‘ rope’ may
be obtained in fine condition, viz. Petershill and Galabraes Quarries,
near Bathgate; Tartraven Old Quarry, near Linlithgow; Charles-
town Quarry, near Inverkeithing ; Roscobie Quarry, near Dunferm-
line; Laddedie Quarry, near Oupar; Airfield, near Cousland by
Dalkeith. From two other localities we have similar “rope ”-like
bodies exposed on the surface of some weathered shale which appear
to differ from the typical H. parallela in certain particulars. They are
of considerable length, forming long undulate bundles, the rods being
far finer than in H. parallela, quite hair-like and apparently retaining
their size throughout the whole mass in a much more constant man-
ner than in the described form. I have not yet seen sufficiently
complete examples of H. parallela to say whether this is only a
portion of an example of that species or a distinct form. I had, how-
ever, provisionally labelled the specimens in question H. Youngi, after
Mr. J. Young, F.G.S., who has been chiefly instrumental in working
out the affinities of the long-known Serpula parallela, M‘Coy, and
as such I shall keep them until further evidence is acquired.

Locality and Horizon. — Hillhead and Whitfield Quarries, near
Macbiehill Station, shale above the No.1 Limestone, Lower Carboni-
ferous Limestone Group.

Collector, Mr. James Bennie.

REVIEWS.

J.—Avus Irtayp. Von Dr. Arnoztp von Lasautx. Mit 26
Abbildungden in holzschnitt, 1 Karte von Inland, und 1
Tafel in Lichtdruck. (Bonn, 1878.)

N the summer of 1876, Dr. von Lasaulx, in company with his
colleague, Dr. Ferdinand Roemer, of the University of Breslau,

paid a long-meditated visit to “the Green Isle,” and in the hand-
some volume before us we have the recorded impressions of one of
the travellers, not only on the physical and natural history of the
country, but on its inhabitants and institutions. It is certainly
highly to the credit of the author, and illustrates his industry in
observing the scenes around him, and in collecting information from
every available source, that within the space of a three-weeks’ tour
he should have succeeded in making himself so fully acquainted
with the scenery, physical features, and geology of the country,
together with the specialities of its inhabitants. As regards the
latter, we think he is on the whole unduly depreciatory, and scarcely
does justice to the great strides which art and civilization have

120 Reviews—Prof. A. von Lasaula—Aus Irland.

made within the existing generation; with regard to the former, he
is generally pleased, sometimes delighted and enthusiastic.

Having spent a few days in Dublin, examining the museums,
the churches, and public buildings, including those of the Univer-
sity, which he highly admires, and having provided themselves
with geological maps, guide books (not always reliable), and Geo-
logical Survey ‘“Hixplanations” (which are always reliable), our
travellers take the train to Killarney, where they spend several
days exploring the lakes and mountain passes, and climbing Man-
gerton (2754 feet), from which they enjoy a panoramic view which
is graphically described. We have very minute descriptions cf the
geological structure of the lake district and mountains; and the
author recognizes in the grand E. and W. flexures of the mountains
of Kerry, the prolongation of those which have disturbed and con-
torted the Carboniferous and Devonian rocks of Belgium and North
Germany. At p. 75 we have a table. which is intended to bring
into parallelism the Lower, Middle, and Upper Devonian beds of the
Hifel, the neighbourhood of Aachen (Aix-la-Chapelle), Westphalia,
and the South of Ireland; and certain beds of nodular limestone and
calcareous shale observed on the flanks of the mountains near
Muckross are placed (with some hesitation) as the representatives
of the ‘‘Cypridinen-Schiefer, Goniatiten-Schiefer, und Cuboides-
Kalke, etc.,” of the Hifel. We fear, however, such a comparison
cannot be maintained. The beds which Prof. von Lasaulx refers to
are really Carboniferous, nor are there any marine limestones in the
Old Red series of the South of Ireland. On the volcanic phenomena
of “the Devil’s punch-bowl,” and the characters of the old lavas and
ash-beds, our author’s observations are accurate and suggestive.

The appearance of some native women accompanied by a lad prof-
fering our travellers some of the ‘‘ wine of the country,” and thus
described: ‘Die Gestalt und die Gesichtsbildung dieser Frauen
war auffallend. Hs waren feingebaute, schlanke, aber doch volle
Figuren, die nicht ohne eine gewisse Hleganz baarfuss tiber die
rauhen Blécke schritten, mit tiefschwarzen, glinzenden Haaren
und dunkelbraunen Augen,” ete., gives our author an opportunity
for an ethnological excursus, in which he draws a very clear distinc-
tion between the Celtic and the “ Milesian” inhabitants of this
part of Ireland, the latter being the descendants of the Spanish
settlers who from time to time colonized the country. From
Killarney the author returned to Dublin, and from thence explored
some of the glens of Co. Wicklow, including that of Glendalough,
with its ancient ecclesiastical buildings. With the minerals in the
metamorphic rocks bordering the granite, and those in the granite
itself, the author is greatly interested; but time, apparently, did not
permit of his paying much attention to the very striking glacial
phenomena of that region.

The remaining portion of the volume is devoted to the North of
Ireland. Having accepted the proffered hospitality of the noble
owner of Florence Court, the author had an opportunity of ex-
amining Lord Enniskillen’s splendid collection of fossil fishes, with

Reviews—Prof. Hull’s Physical Geology of Ireland. 121

which that of Sir Philip Egerton is alone comparable. A list of
the genera and species drawn up by his Lordship has already
appeared in the Gxroxn. Mac.! In this district he had an ex-
cellent opportunity of examining the succession of the Lower
Carboniferous rocks, from their base along the shores of Lough Erne,
where they repose on the Old Red Sandstone, up to the Millstone-
erit ridge of Cuileagh, which rises 2,187 feet above the sea. The
limestone in this district is rich in coralline, and crinoidal remains ;
Pentatrematites Derbiensis, Platycrinus, etc., and the author records
the occurrence of Amphoracrinus Gilbertsoni, in the cliffs of the
upper limestone which rise boldly above Florence Court Park.
Need we say, that with Lord Enniskillen and his family our author
is fairly captivated, and that he bids farewell to the hospitable
“Schloss,” with feelings to which he gives expression in the follow-
ing passage: ‘Als wir uns in der Halle der irischen Riesenhirsche
herzlich von unsern gastlichen Wirthen verabschiedeten, trugen wir
eine unausloschliche, freundliche Erinnerung an das griine Florence-
court und seine edlen Bewohner von dannen. Modgen sie, wenn
dieses Blatt ihnen zu Gesichte kommt, es als ein Zeichen unserer
Verehrung ansehen und der deutschen Gaste aus dem fernen Osten
wohlwollend gedenken ” (p. 135).

From Enniskillen the author and his companion proceed to the
north-east, travelling along the valley of the noble river Foyle to
Londonderry, and thence proceeding to the Antrim coast, with the
scenery and geology of which he is greatly delighted. Visiting the
town of Antrim on his way southwards, he examines the celebrated
‘Round Tower ” of that place, of which a picture is given (p. 161),
as well as the trachytic district of Tardree Hill; and here the author
justifies his high reputation as a mineralogist, by the discovery of
that rare form of silica, called “tridymite’’ by Vom Rath, which
appears to be abundant in the drusy cavities of the trachytic lava.
Further on his way, he visits the celebrated plant-bearing beds of
Ballypalidy of Miocene age; and after a short stay in Belfast,
finally takes his departure tor Scotland, to be present at the meeting
of the British Association.

Ii.—Tue Puystcan GroLtogy anp GroGRAPHY OF IRELAND. By E.
Hutt, M.A., F.R.S., Director of the Geological Survey, Ireland,
and Professor of Geology in the Royal College of Science,
Dublin. Post 8vo. with 2 coloured maps and 26 wood en-
gravings, pp. xvi. and 291. (London: Stanford, 1878.)

(First Notice.)
E have often wondered why our Geological Literature con-
tained no general key to the structure and features of Ireland.

That the ‘Green Isle’ could boast of more than one ‘son of the

hammer’ who was competent to lay such a summary before his

brother geologists, we knew, not only from the enjoyment of

personal intercourse, but from an acquaintance with their published

labours. Yet we had it not. More than five years since, the
1 See Grou. Mac. 1869, Vol. VI. p. 556.

122 = Reviews—Prof. Hull's Physical Geology of Ireland.

admirable Physical Geology and Geography of. Great Britain, by
Prof. Ramsay, had reached its third edition, and had been entirely
remodelled ; while North Britain could point with just pride to
Geikie’s interesting Geology and Scenery of Scotland. True the
detailed map of Griffith, and the many reductions of, and improve-
ments on it, which have resulted, formed in themselves excellent,
and to a large extent sufficient, guides to a knowledge of the general
structure of a country, essentially so simple as that of Ireland.
And we have no doubt some feeling of this kind, and a desire that
one who had already done so much for the Geology of Ireland,
should, if he himself wish it, have the opportunity of making
that country still more his own kingdom, by adding to his map a
general description, kept several from attempting a task for which
they felt their old master and guide was so vastly more competent
than they. But whatever the cause, it has been reserved for Prof.
Hull to supply this want in the little volume now before us.

Like all contributions of the author, the work is carefully com-
piled, and is a singularly full though much compressed statement
of facts, given in the simplest language, with, we rejoice to say,
very few attempts at oratorical effects, or fine writing. It thus
carries with it the conviction of truth and sincerity which we are
always disposed to concede at once to a simple and full exposition of
facts: it is, in reality, so essentially dependent for its conclusions on
the abundance of its details, that no single or hasty reading will
suffice to the student.!

The author presupposes, wisely, we think, an acquaintance with
the elementary principles of the Science of Geology on the part
of his readers, and, therefore, passes at once to an enumeration of
the various formations which occur in Ireland, the extent and
position of the areas they occupy, and their mutual relations. To
the discussion of these questions the first of the three parts into
which the book is divided, is given. This is also by a good deal the
longest and most detailed division, occupying 116 pages. The
Physical Geography occupies the second part (pp. 117-210) ; and the
third part (pp. 211-272) is devoted to the ‘ Glaciation of Ireland.’

A general summary of observations over a wide area, so as to
give a comprehensive idea of the relative structure and history of
the different points, offers no fitting opportunity for the detailed
discussion of any special views, or the exposition of any novel
speculation, and we shall therefore better elucidate our author's
work by a very brief resumé of the information given, than in any
other way.

1 With this fullness and care, we notice also several things which convey to our
mind a distinct impression that the work has been hastily written and too hastily
printed. There are errors of grammar, errors and contusion in the spelling of
names, and phrases and idioms which, though perhaps intelligible, are certainly not
elegant, which a very little more care and time would have avoided. We notice
these little defects at once, not as wishing to convey the idea that the real value of
the work is diminished by such blemishes, but because we feel confident that a
second edition will soon be called for, and we would gladly see even these little blots
polished out.

Reviews—Prof. Hull’s Physical Geology of Ireland. 123

The geological structure of Ireland, on the whole, is singularly simple. Over
more than nine-tenths of the total area we find no rocks of a date later than Pale-
ozoic (Upper Carboniferous, with a trace of Lower Permian, if these be Palzozoic)
until we come to the more recent Tertiary, post-Pliocene, or drift deposits, as the
author calls them, that is, we have no representatives of any but the oldest and the
newest groups of rocks; while even in the remaining small area in the north-east
of Ireland, although some of the Mesozoic rocks are represented, there is still an
immense period (including all the time represented in the closely adjoining counties
of England, by the wide-spread, and as regards both the agricultural wealth and the
loveliest scenery of the country, all-important groups of the Lias, except the lowest
beds, the entire series of the Oolites, the Wealden Purbeck, and the Lower Cretaceous
rocks) which is in Ireland without a single record. All the evidence, also, would
seem to point to the fact, that this absence of the rocks is due to an original absence
of deposition, and not to any subsequent denudation ; and would, therefore, indicate
that for the vast lapse of ages, represented by all the rocks between the Carboniferous
period and the commencement of the post-Tertiary, the greater part of Ireland was
elevated into dry land, while the sea covered widely the whole central portion of
England. The little tabular view (given on p. 3) of the different formations on
both sides of the Channel, showing which are present and which are absent, will be
found very useful.

Briefly referring to the Cambrian rocks, so well known to visitors of Dublin, from
their readily accessible positions at Bray Head and Howth, to the south and north of
Dublin Bay, the author proceeds to the Lower Silurian beds, which rest unconform-
ably on these older rocks, the gap between the two representing the absence in
Treland of the Lingula Flags, or Upper Cambrian of North Wales (English Survey
classification). These Lower Silurian deposits are among the most interesting to
the student of Irish geology, from the fact that they occur in two very distinct
phases, now perfectly established as representative one of the other. In the one
they are still unaltered, and still full of fossils, though indurated, contorted, and dis-
turbed; in the other they have become highly crystalline, metamorphic schists,
gneiss, hornblende schists, ete. The age of these rocks is well fixed both by position
and by fossils, as belonging to the great Lower Silurian, and being probably about
that of the Caradoc and Llandeilo groups. Beds of limestone occur, though rarely,
and contain fossils representative of the Bala beds. These rocks, in their meta-
morphic condition, occupy four areas in the north and north-west of Ireland.
1. West Galway and part of Mayo. 2. North of Clew Bay. 3. ‘The Ox Mountains
from Lough Cong to Lough Gill. 4. Donegal and Derry. To the east of the
island there is a north-eastern area in the highlands flanking the Mourne Mountains,
and north of Dundalk, and a south-eastern extending from near Dublin to the coast
of the county of Waterford.

There are only two areas of any great extent of Upper Silurian rocks in Ireland
—one near the Killaries, in Galway, between Lough Mask and the Atlantic. And
this is of high interest, as affording undoubted evidence of the date of the metamor-
phism of the rocks which we have just noticed—evidence which the country of
Scotland, so rich in metamorphic phenomena, has not yet afforded. There the
rocks immediately resting on the metamorphic Lower Silurian beds are the Old Red
Sandstone, and it is therefore only possible to assert that the metamorphism took
place prior to the formation of the Old Red Sandstone. But here—in Galway—
resting on metamorphosed rocks of unquestionably the same general age as those
of Scotland, we have, quite unconformably, masses of conglomerates, grits, shales,
etc., formed out of the debris and waste of these metamorphic rocks, and which
themselves, though containing beds of volcanic ash, and sheets of felspathic lava,
—evidence of contemporaneous volcanic action during their deposition,—still exhibit
no trace of that wide-spread and deep-seated metamorphic action so strongly developed
in the lower beds. ‘These beds in Galway probably represent the Wenlock and
Ludlow beds of England. The only other important locality is near Dingle, where
a very large series, probably representative of the whole Upper Silurian series of
England, occur. These have derived some special interest from the occurrence above
them, and conformable to them, of the series to which Jukes gave the name of
‘ Dingle beds,’ a great thickness of grits, shales, and conglomerates, which are them-
selves unconformably covered by the lowest beds of the Old Red Sandstone.

The absence in Ireland of any marked representative of the true Devonian, or
marine equivalent of the Old Red Sandstone, is noted, and the distinctively Irish

124 =Reviews—Prof. Hull’s Physical Geology of Ireland.

characters of the Old Red as a formation insisted on. This vast thickness of sand-
stones, conglomerates, and slates appears to have been thrown down in the waters of
a large lake or great inland sea, as first pointed out by one to whom English geology
is largely indebted for broad philosophical speculation in its physical history, Mr.
Godwin-Austen (not Austin as printed), or rather in two lakes separated by a great
ridge of Silurian land crossing Ireland, and what is now the Irish Channel, into North
Wales and Central England, though in all probability the basin formed to the south
of this ridge did not extend so far in the south-east. In the northern area the
rocks have much the same character as their representatives south of the Grampians
and in Central Scotland; but in the south and south-west the formation shows two
distinct members—the upper of which (essentially Irish) very distinctly passes into
the Carboniferous rocks above, the lower forms the greater portion of the extensive
counties of Cork and Kerry, and forms some of the most elevated ground in Ireland.

About one-half of the entire area of Ireland is occupied by rocks of the Car-
boniferous series, chiefly confined to the lowermost members, the Carboniferous slate
and the Carboniferous limestone. This latter, which was with justice called the
Mountain limestone in England, ought more properly in the sister-isle to be called
the Plains limestone, because, excepting in parts of Leitrim, Sligo, and Fermanagh,
where it rises into bold isolated hills and escarpments, it is found only under the
wide-spreading plains of the country. The Upper Carboniferous beds, including
some of the Coal-measures, are now only represented in a few detached areas,
barely sufficient to mark the former widely-extended area of the formation. The
Carboniferous Limestone itself presents in Ireland three acknowledged divisions.
(1) The Lower Limestone, generally a pure, fossiliferous limestone, many of the
beds yielding richly-colowred and handsome marble; (2) the Calp, a dark-coloured
earthy and shaly series; and (3) the Upper Limestone, often of a lighter grey colour
than the lower, and often full of ‘‘Chert,’’ both in irregular layers and masses like
the flints in chalk. Volcanic rocks occur in places, showing the existence of such
action during the deposition of these rocks. Representatives of the ‘* Yoredale beds,”
and of the ‘‘ Millstone-grit”’ of England also occur; as well as of the ‘* Gannister
beds.” Of the Upper Coal-measures, whatever may have been their original extent,
there now remain only two or three very limited areas, as at Castlecomer in the
counties of Carlow and Kilkenny, and Killenaule in Tipperary (whieh may be
considered parts of the same general area): and at Coal Island in Tyrone.

Permian rocks have only been recognized in a few places; the Lower Permian
only in one; viz. a few feet of conglomerate and breccia resting on the Lower
Carboniferous Limestones of Armagh. The Magnesian Limestone is represented,
though poorly, near Cookstown in Tyrone, and at Cultra, on the south shore of
Belfast Lough.

Of the Mesozoic rocks, as already stated, no representatives are known in any part
of Ireland, excepting in the north-east; there the Triassic rocks form a narrow
band, encircling the basaltic region of Antrim and East Derry, generally occurring
in the lower ground of river valleys. The two groups of the Bunter Sandstone
and Keuper are both recognizable, the former chiefly in Belfast Lough and near
Dungannon, etc., and the latter between Larne and Carrickfergus, marked by the
presence of bands of gypsum and extensive beds of rock-salt (Carrickfergus). At
Scrabo, near Newtownards, the Triassic sandstones are capped by masses of dolerite,
and are also penetrated by horizontal sheets, and vertical dykes of basalt, intersecting
each other in various directions, and affording a magnificent opportunity for the
study of such phenomena.

The Lower Liassic and Rheetic beds occur together in a few places round the north-
east coast, as at Colin Glen, near Belfast, Larne, and Portrush ; at the latter locality
indurated and conyerted into a kind of Lydian stone, by contact with a sheet of
intrusive dolerite. At Larne the beds are of light blue and deep grey clays, with
earthy limestone, containing Gryphea incurva, etc., and below these dark shales with
Avicula contorta.

There are no representatives of the main portion of the Lias of England, nor of
any of the numerous divisions of the Jurassic rocks, as yet known in Ireland. They
very probably were never deposited ; but if they were, they had been entirely removed
again before the period of the formation of the Upper Cretaceous rocks. For there
is no representative of the lower part of this great series either; we find only the
Upper Greensand and the Chalk with flints. The whole group varies in thickness,
but never exceeds a maximum of about 350 feet. The upper surface has been

Reviews—Prof. Hull’s Physical Geology of Ireland. 125

largely eroded, and an irregular bed of flint-gravel, with red ochre filling up the
hollows in the rocks, generally occurs between the chalk and the sheets of volcanic
lava by which it is covered. There has not been much contortion or disturbance of
the beds, which are, for the most part, nearly horizontal, but as a whole they form
a shallow basin-shaped area (the central depression of whichis marked approximately
by the course of the River Bann), dipping towards this depression from the sides.
We do not see that our author notices the fact, which is certain to be among the
first to strike the stranger, that the Chalk of Ireland is a hard, compact, white
limestone, without any of the soft granular and powdery character distinctive of the
English Chalk.

The occurrence of the Cretaceous formation in this isolated locality, so far from the
nearest north-west point of its area in England, is of much interest, as bearing on
the question of its furmer greater extension. Prof. Judd has also found Cretaceous
rocks in the Isle of Mull, far away to the north, and the sharply truncated edge of
the formation along its western and eastern faces in Ireland would seem to establish
that it formerly covered a considerably larger area. It is not improbable that it
was even connected with the English area at the time of its deposition; and if so, it
would appear probable, further, that this connexion occurred over the lower country
or depression which now separates the mountains of Wales from those of Cumberland
and North Lancashire. To the west, it was probably limited by the highlands of
Donegal and Sligo.

The old volcanic rocks of Antrim, long classical ground to the geologist, which
cover nearly all the area in that county, as well as considerable portions of London-
derry and Tyrone, forming generally a very well marked and elevated plateau,
succeed to the Cretaceous beds just noticed. Prof. Hull (Brit. Asso. 1874) had already
pointed out that these were capable of a three-fold division: the earliest stage
marked by trachyte porphyry (Sandy Brees, Temple Patrick, Hillsborough). The
masses are very limited in extent as compared with the succeeding overflows. ‘The
rare mineral Tridymite has been found in the cavities of these rocks. ‘The actual
age of these outbursts is unknown, but Prof. Hull thinks they probably belong to
the later part of the Eocene period. ‘They are thus possibly the only Eocene rocks
in Ireland. The middle stage of the volcanic rocks is characterized by vesicular
amygdaloids, and basalts, often separated by beds of red bole, and succeeded by vol-
canic ashes and larger bombs of trap. These are supposed to have been subaerial
discharges of volcanic matter, the intensity of the volcanic action being succeeded
by a period of repose, during which peculiar beds of pisolitic iron ore, and layers of
fine débris of the rocks, containing plant-remains, were deposited, probably in lacus-
trine waters. These plants have proved similar to those found in the Isle of Mull,
and have thus been taken to indicate a similar Miocene age. And then, finally, after
this period of repose, the voleanic forces again became very active, and gave forth
vast flows of lava, now successive beds of columnar basalt, which are often seen
resting directly on the thin beds of iron ore, or on a bed of lignite.

The total thickness of these volcanic rocks is often more than 1000 feet: all
actual craters and cones have long disappeared by denudation, but ‘necks’ are still
to be traced through which some of the volcanic outbursts were forced up. These
have been noticed by other observers, but our author brings forward as an instance,
a locality visited yearly by hundreds of tourists, namely the now detached and ruined
Castle of Dunluce between Portrush and the Giant’s Causeway—which he states is
built on a mass of agglomerate, originally forming one of these ‘necks.’ In a sub-
sequent page, however (p. 70), he says his views on this point have been recently
altered during a visit to the localities along with Prof. Ramsay and Mr. Traill, and
that he is now disposed to view these cases as simply pipes formed by filtration out
of the chalk, into which the basaltic masses have fallen or slipped down, thus giving
rise to their fragmental appearance.!

1 Those who are curious to trace out accurately the successive steps by which
opinions are formed, put forward and obtain currency, in such matters, will be
amused to follow up this case of supposed ‘necks’ in the basaltic country of Antrim.
Let them look first then to Portlock’s Report on Londonderry, ete., 1843—more than
thirty years since, and at p. 92 they will find a carefully drawn view of one of the
instances referred to by Prof. Hull, and an equally carefully drawn up description of
the appearances presented by the rocks. Portlock says: ‘“‘The trap penetrates
into the chalk, and forms a conglomerate with the flints and fragments of chalk it

126 Reviews—Prof. Hull’s Physical Geology of Ireland.

After a brief notice of the frequent occurrence of basaltic dykes in the country
adjoining these volcanic rocks, the author proceeds to the only known Pliocene
beds in Ireland. These occur as quietly deposited beds of clays, filling in a part of
the older extent of Lough Neagh. They now extend 80 to 90 feet above the level
of the lake, and have been pierced to a depth of 300 feet, the maximum thickness
being nearly 500 feet. They rest on an eroded surface of the Miocene basalt, from
which they are separated by a bed of rude conglomerate formed by masses of these
basaltic rocks. ‘they are generally stiff and plastic bluish clays, much used for
coarse pottery, etc. In them remains of what is described as an Unio! have been
found, and also of plants—the whole character of the beds indicating a quiet
deposition under tranquil waters in an equable if not a warm climate. They were
the old lacustrine delta deposits of the Upper Bann and other streams entering
Lough Neagh from the south. The Pliocene period is but sparingly represented in
any part of the British Islands, and these deposits become of even greater interest
from the absence of any contemporaries. Of the Pliocene period in Ireland, Prof.
Hull says, ‘‘ Ere it set in, the volanic fires had smouldered away. It was an age of
calm repose, separating the period of volcanic activity on the one side from that of
frost and ice on the other; and during its continuance the ordinary agents of
denudation—rain, rivers, and sea waves—carried on their operations without unusual
interruption, but with marked effect in modifying the physical features of the north
and adjoining districts of Ireland.” (p. 76.)

This brings us to the close of the Tertiary period. There still remains, however,
along series of deposits to be noticed, which in reality cover more than three-fourths
of the whole area of the country, and to the presence or absence of which a very
large amount of the varying characters of its scenery is due. Important, however,
as they are, we cannot afford space for more than the briefest notice of these “ Post-
Pliocene or Drift-deposits,” as Prof. Hull classifies them,—the Glacial and post-
Glacial clays, sands, gravels, etc., and the still more recent deposits, forming raised

has in its progress enveloped. Many, but not all, the flints are changed to red, and
the chalk fragments are comparatively few, the lime having, it is probable, contri-
buted to form the enveloping paste, which is in part rotten and soapy. Some of the
immersed fragments of chalk are powdery to the touch, though still retaining a
definite form, and such is also the case with the flints. The great body of the trap
is here concretionary ; and as the softer portions wear away, the harder projecting
lumps look like huge boulders in a rude conglomerate. The bottom portion is
obscured by rubbish, so that it is impossible to say whether the trap has risen
through the gap, as through a crater, or has been poured into it from above, but on
the east side the chalk in a considerable mass rests upon trap, and is at the same
time overlaid by it.”” Now let him turn to Jukes’s Manual of Geology, edited by A.
Geikie, 3rd edit., 1872, and at p. 271 he will find a figure (fig. 107) tended to re-
present the facts seen at the same locality exactly—trom a sketch made by Prof.
Geikie himself. After noticing where this assumed ‘neck’ occurs, he says: ‘‘ A
cavity, measuring about fifty yards across at the top, has been blown through the
chalk, and also through a previously erupted sheet of basalt, and this cavity, after,
perhaps, serving as an orifice for the discharge of some of the tuffs of the district,
was finally filled up with a coarse mass of rubbish, consisting of blocks of basalt,
chalk, etc., imbedded in a dirty green gritty trappean paste.” The writer thinks it
evidently quite beneath his consideration to think of giving any proofs of these boldly -
asserted views—or to offer the slightest explanation of how his ‘gritty trappean
paste’ was formed, or when. Then as the last step in the history of this curious
case, we have Prof. Hull (p. 56) saying: ‘‘The old necks are choked up by
bombs which have been blown into the air, and in falling back have filled up the
throat,” referring to this very case, near Portrush, and then (on p. 70) he withdraws
from this view, and holds these cases to be old pipes in the chalk, ‘into which the
basaltic masses have fallen or slipped down,” that is, we presume, after they had
been to a considerable extent at least, if not entirely, cooled and hardened. Has he
any proof of this? If so, why is it not noticed? After the student has traced the
successive steps in the history of this sketch, and seen the several additions in the
story, which each of its narrators have added—additions for which they were indebted
purely to their own poetic imaginations—we cannot help thinking that, so far as any
real truth, objective truth, is concerned, he will return to the description of thirty
years since, where he finds the limits of knowledge and ignorance clearly noted and
candidly avowed, in preference to the apparently more finished, perhaps, but less
thorougly established dogmas of recent observers.
1 See Grou. Maa. Dec. 1876, p. 557.

Reviews—Prof. Hull’s Physical Geology of Ireland. 127

beaches, river terraces, etc., which are so numerous and widely spread. The author
still adopts the same classification as he formerly did, of these representatives of
“The Great Ice Age,” and makes three groups. (1) The Lower Boulder-clay or
Till; (2) Middle Sands and gravels, the Limestone gravels of Ireland; and (3) the
Upper Boulder-clay, and notices in some detail the peculiar circumstances under
which each of these occur. It will be sufficient here to indicate the conclusions,
that the earlier period indicates a time when the surface of the country was more
elevated than now, but was somewhat in the same condition as the north of Green-
land, ete., is at present, that is, was covered with a continuous ice-sheet of great
thickness, and in continued motion in given directions. Secondly, a period of com-
parative depression, amounting probably to 1500 feet, accompanied by an ameliora-
tion of climate, and an overspreading of the land by the ocean, when water-arranged
deposits of sands, gravels, etc. (often containing shells), were formed; and thirdly, a
period of gradual elevation, when glaciers again accumulated in local centres around
the higher grounds which produced the true glacier moraines, still so frequent in the
highlands of the country, and from which drifting icebergs probably conveyed, and
dropped at intervals over the country, the boulders which are now found resting on
the Middle Sands in many places. It is, however, but right to notice the fact that
this classification, although adopted by many, and now before geologists for many
years, has by no means commanded universal acceptation. There are still many who
hold that the subdivisions noticed are merely local, and by no means so general as to
afford sufficient data for the large and wide generalizations which have been based on
them. Our author does not himself accept some of the views of other glacialists.
We find in his pages no evidence of a belief in the second outspreading or return of
a great ice-sheet, after the formation of the Middle Sands, although this is the view
of others, and he has been careful to explain fully the much more limited extent,
and frequent total absence of the Upper Boulder-clay. The Lower Boulder-clay is
by far the most widely distributed of the three groups, occurring in greatest mass in
the lower grounds and deeper valleys. Most of these valleys have, in fact, been re-
excavated out of it, detached patches of it being left on the side slopes. But even
this lower division is not universally present, and even in the lower grounds there
are instances where considerable areas are entirely free from it, while closely ad-
joining areas are thickly covered. The Upper Boulder-clay, on the contrary, is much
more sparingly distributed, and in many parts of the country it has never been
deposited. It further often shows distinct signs of arrangement in layers or strata,
and has therefore been formed or rearranged by water, while the gravels and sands,
on which it is said to rest, give evidence of erosion by water action, but do not
appear to have been fairly ground down, or displaced by a mass of ice. The upper
limits of this deposit appear to be less than 1000 feet above the present sea-level.
Then we have a series of terraces in the highlands which are attributed to succes-
sive formation along shores as the land was emerging from its depression during the
Middle Glacial period, at a time when the land was gaining on the sea, and when
pauses in the upward movement took place. The “ Eskers”’ are noticed as “ the
results of tidal and other currents acting on the soft materials of the drift, as they
oscillated within narrow channels, bounded by the ridges of the unsubmerged land,
piling them up along tortuous lines in the form of embankments” (p. 99). Mr.
Kinahan’s distinctions of Bar-eskers and Shoal-eskers are alluded to. There is then
a full notice of Local Moraines, or true Glacier Moraines, both lateral and terminal,
and numerous instances given both from the Wicklow and the Galway Mountains.
We then pass to Raised Beaches and River Terraces; and the evidences of the suc-
cessive steps in the elevation of the land to its present level are brought down to the
“15 foot beach,” which is traced along the coast from the north to Dublin, where it is
shown probably to merge into the old estuary terrace of the river Liffey, on the flat
surface of which some of the principal parts of the capital of Ireland are built
(Custom House, Post-office, Sackville Street, Bank of Ireland, University, etc.). In
this terrace, with the shells have been found flint implements, establishing the fact
that it has been formed since the occupation of the country by its early inhabitants.
This, therefore, connects the Geological with the more purely Archeological portion
of the history. A capital little sketch geological map, coloured by hand, forms the
frontispiece to the book, and to those who have not at hand any larger or more
detailed map, it will give a fair clue to the general distribution of the various rocks.

(To be concluded in our next Number.)

128 Reviews—Prof. Geikie’s Geological Map of Scotland.

IIJ.—Geoxoercat Mar of Scotntanp. By ArcursaLtp Getnie, LL.D.,
F.R.S., Director of the Geological Survey of Scotland, Murchison
Professor of Geology in the University of Edinburgh. (W. and
A. K. Johnston and Co.: Edinburgh, 1876.)

F late years the work performed by the Official Geological

Surveys has made an immense addition to our knowledge of
the characters and inter-relationships of the rock-formations of

Britain. This addition, however, has been almost wholly confined

to two departments of Geological Science. While Stratigraphical

and Mineralogical Geology have advanced with gigantic strides,

Stratigraphical Paleontology has remained almost at a standstill.

Originally occupying the proud position of friend and mentor to

Zoology and Geology alike, extending a helping hand to either,

Paleontology now-a-days seems to bestow all her favours upon the -

former. The philosophical zoologist has gradually been forced to

recognize the inestimable value of her counsel, and to expect from
her alone the solution of some of his most perplexing problems of
life and its distribution. The practical geologist has simultaneously
been losing faith in her monitions, and at present openly cherishes
the belief that the day is at hand when he can safely dispense with
her reluctantly accepted assistance altogether. Conscious of his
great inferiority to the practical geologist in the amount and re-
liability of his data, and disconcerted by the hazy doctrines
of representative forms, homotaxis, colonies, migrations and the
like, the paleontologist in general is compelled to speak with a
diffidence that has inevitably led to the almost total neglect of his
opinion on geological classification. The pure stratigraphist, on the
other hand, certain of his facts, accepts only such of the conclusions
of his paleontological brother as may happen to coincide with his
own, and makes his arrangements on mineralogical and stratigraphi-
cal data alone, in the confident assurance that “the domination of

Paleontology is gone for ever.”

Perhaps no more vivid illustrations of this tendency can be seen
than in the beautiful map before us. Here, in one area, two for-
mations, hitherto held by geologist and paleontologist alike to be
totally distinct, are considered as one, simply on the grounds that
they agree locally in physical conformity and in mineralogical
similarity ; although elsewhere they are separated by thousands
of feet of intercalated strata. In another district the apparent
stratigraphical evidences are so consistent that they are held to be
demonstrative of the co-existence in Scotland of distinct groups of
marine animals, which in other countries are strictly confined to
wholly different formations.

The microscope of research has so magnified the geological field
that each formation has practically become a system,—crowded with
detail, and demanding a multiplicity of attainments, and a lifetime
of application for its proper investigation. Thus, day by day, the
average geologist becomes more and more of a specialist ; possessing,
it may be, a knowledge, more or less perfect, of that minor section
of his great subject which the accidents of training and locality have

Reviews—Prof. Geikie’s Geological Map of Scotland. 129

made familiar and attractive to him, but forced to found his ideas
respecting the rest of the geological world upon the data furnished
by the discoveries and speculations of others. Scattered as these
are in the maps and memoirs of the Survey, and in the pages of
multifarious and often inaccessible scientific publications, he cannot
be sufficiently grateful to those who have the opportunity and
patience to reduce this mass of heterogeneous material to order, and.
bring a summary of the more important results before his eyes at a
single glance in a general geological map like the present.

We know of no other map of this class in which this task has
been so perfectly and so conscientiously performed. Prof. Geikie, in
his official capaeity as head of the Scotch Survey, enjoys exceptional
advantages in the command of numberless geological details as yet
unpublished, and in his perfect familiarity with the ground mapped
by himself and his subordinates. But he also brings other and far
more vital qualifications to the execution of his task. No one has
personally added more to our knowledge of the physical structure
of Scotland, or has thought more profoundly over the many unsolved
problems of its geology. There are few districts in the country to
which his eloquent writings have not imparted a new interest; and
there is scarcely a single formation in its geological series in which
he has not added to our previous knowledge by discovery or original
observation. ‘To him also is mainly due that excellent little map of
Scotland published by Johnston in 1862, in which the so-called
Laurentian, Cambrian, and Silurian rocks of the Highlands were
laid down, and the first successful attempt was made to delineate
with correctness the distribution and mutual relationships of the
Scottish deposits in general.

In the compilation of his facts the author has not only availed
himself of the vast mass of new details worked out by himself and
the officers of the Geological Survey, who have now practically
finished the mapping of that portion of Scotland lying to the south
of the metamorphic rocks of the Highlands, but he has profited to
the full by the facts detected in other areas by Harkness, Jamieson,
Judd and others. The topography of the map is by Mr. T. B.
Johnston, and is perfect in its way. By the omission of all hill-
shading, and by the use of skeleton-letters for the names of the
chief natural features, etc., much of the ground of the map is left
bare, and room is thus gained for the insertion of a large amount of
geological detail.

The system of colouring adopted is that which has long been in
use in the publications issued by the Geological Survey of Britain
—the different shades of red being employed almost exclusively to
mark the various classes of igneous rock. This plan is so simple
and convenient in application, and so valuable as a distinct aid to
the memory, that it should be employed invariably upon all maps,
where several different formations are represented. One other
feature of this map cannot be too strongly commended. With one or
two minor exceptions—and these perhaps unavoidable—all the tints
are quiet in tone. We have none of those painful contrasts of faint

DECADE II.—VOL. V.—NO. III. 9

180 = Reviews—Prof. Geikie’s Geological Map of Scotland.

and almost invisible washes placed side by side with glaring
splashes of brilliant paint, which disfigure even some of the best of
the Survey maps. Here, while the brighter colours mark at a glance
the localities of the igneous interruptions to the general continuity
of the more soberly tinted aqueous deposits, the general tone 8&7 the
map is quiet and subdued. Nota single detail is obscured, and the
general effect is grateful and pleasing to the eye.

In indicating the main points of advance made by the present
map upon its predecessors, we shall pass over the earlier geological
maps of M‘Culloch and Nicol, and restrict our observations to a
comparison with the small map of Murchison and Geikie already
referred to, and which was professedly the first sketch for the geolo-
gical map of which the present publication is the completed design.

Beyond the more exact delineation of the boundaries of the
Lewisian gneiss and the Torridon sandstones, we are presented with
nothing new in the fundamental rocks of Sutherland and Ross. The
larger scale of the map, however, not only admits of the more precise
definition of the limits of the various divisions of the Highland
metamorphic rocks, but a vast amount of new detail is inserted. In
the all-important area of the North-west Highlands the great Durine
band of quartz-rock is seen to be by no means so broad or so in-
variable a geographical feature in that district as appeared from the
earlier map, nor do its two limestones always appear to occupy the
same relative places in the general series.

The quartz-rocks which imbed the classic limestones of Glen Tilt
are no longer figured as forming a vast elliptical island in the meta-
morphic schists, but are seen to be extended far to the north in the
wilds of Badenoch, and to form four narrow strips running through
Banff and Aberdeen to the shores of the German Ocean. On the
other hand, although the line of anticlinal axis, running from Loch
Tay to the mouth of Loch Fyne, is distinctly laid down, the great
sheet of supposed quartz-rocks which formerly accompanied it, and
was believed to be prolonged to the Mull of Cantire, is now coloured
as of later age, and the limestones which partially defined its upper
boundaries are now theoretically placed at the summit of the suc-
ceeding schistose formation, instead of at its base.

The clay-slate formation of the older geologists again finds its
special place and colour upon the map, and we recognize with
something akin to pleasure our old and well-nigh forgotten ac-
quaintance, in its original position along the southern margin of the
Highlands. Its geologic place, however, appears to be to the full
as difficult of definition as ever. If we may trust the Argyllshire
sections and the legend on the map, it must be separated from the
basal quartz-rock formation by an enormous series of micaceous
schists. If the Banffshire sections are to guide us, it must repose at
once upon the quartz-rock formation, without the intervention of
any schistose beds whatever.

Turning next to the unaltered deposits of the Southern Uplands,
we notice that the Upper Silurian colouring has been very properly
extended to the schists and flagstones of Langholm and Stobo,

Reviews—Prof. Geikie’s Geological Map of Scotland. 181

which lie to the south of the Hawick rocks, and agree in every
respect with the Coniston Flags and Grits of the North of England.
Although the officers of the Survey have satisfied themselves of the
existence of several important divisions in the so-called Llandeilo
series of greywackes whose contorted beds floor almost. the whole of
the Uplands, no attempt has been made to define their limits upon
the small scale of this map. A new and most valuable feature is
seen, however, in the insertion of the main lines of black shale in
the central districts and Galloway, but no distinction is made
between the so-called Upper and Lower groups. These omissions
are compensated to a certain extent by a marginal section through
the central portion of the Silurians from the Cheviots to Tinto.
Here the Ardwell or Hawick rocks are figured as being covered un-
conformably to the south by the Riccarton Beds of the Upper Silurian,
but the hypothetical nature of the break is carefully indicated
by a note of interrogation. The thin deposit of the Moffat Shales is
shown as reposing upon the Ardwell Beds and passing below the
Queensberry Grits to the south of Ettrick Pen, and on both slopes
of the Moffat Valley. It is a little awkward for this theory that
there are no black shales in this position to the south of Ettrick Pen,
nor for many miles to the north-east; while the extension of this
strike to the south-east would carry us deep into typical Ardwell
Beds. At the same time the black bands on the opposite side of the
Moffat Valley happen to be the most easily demonstrated anticlinal
forms in the whole of the Moffat district.

The numerous patches of calcareous grit and conglomerate with
Caradoc and Llandovery fossils are shown by a distinct colour upon
the map. In addition to the typical area of Duntercleuch, the corre-
sponding strata of Kilbucho, Wrae Hill, Moniave, etc., are marked as
of Caradoc age. In the section they are represented as unconformable
upon the Llandeilo greywackes. This classification has been
extended to the interesting Girvan area. The great fault formerly
supposed to cut off the Llandeilos of the Uplands from the Girvan
beds is omitted, and the Caradoc tint is restricted to the two small
and possibly unconformable patches of Assel and Craighead.

A special and highly interesting feature of this map is the develop-
ment and classification of the rocks which lie between the summit
of the true Upper Silurian and the acknowledged base of the Scottish
Carboniferous Limestone. The long line of fault throwing down
the Red Sandstone of Strathmore from Stonehaven to Loch Lomond
is here, for the first time, shown in its true position; and the
irregular boundary of the basal conglomerate upon the clay-slates
of the southern margin of the Highlands is carefully shown from
the work of Professor Geikie and his assistants. The more im-
portant results of the recent work of the officers of the Survey in
Forfar and Kincardine are filled in. Special care has been bestowed
upon the strangely interlaced group of felstones, ashes, and sand-
stones of the Sidlaws, Ochils and Pentlands, every conspicuous
rock-sheet being laid down with painful minuteness.

Tn accordance with the views broached by Professor Geikie in 1876

132 Reviews—Prof. Geikie’s Geological Map of Scotland.

. the so-called Lower and Middle Old Red Sandstones south of the
Grampians are regarded as constituting a single formation; the
unconformity visible between Tinto and the Pentlands being looked
upon as a local feature dependent upon the igneous action so rife
at that period. In the face of the evidences he has adduced, it is
impossible to resist the conviction that this arrangement, so far as
these beds are concerned, is the one which is most convenient and
most in accordance with the order of nature ; and in these respects
it must be looked upon as a decided gain. His second conclusion,
namely, that the Caithness Flagstones are, in all probability, of con-
temporaneous age with the admitted Lower Old Red Sandstones of
Perth and Lanark, is of too sweeping a nature to be so readily con-
ceded. The author seems fully aware of this fact; for though the
beds are coloured as of Lower Old Red age upon the map, the
original lettering, expressive of their Middle Old Red age, is still
retained.

His third and most important conclusion, that everywhere
throughout Scotland the so-called Upper Old Red Sandstone reposes
with a violent unconformability upon all the underlying rocks, and
shades upwards into the basal beds of the Carboniferous, is made to
do great service. This subformation is here coloured as if of Old
Red Sandstone age, but is bracketed with the Carboniferous. The
detection of marine fossils characteristic of the Carboniferous Lime-
stone in red beds far inferior in geologic position to the theoretical
base of the Cement-Stone group, or Upper Calciferous Series, of
Arran, is very naturally regarded as of immense weight, and is held
as sufficient in itself to demonstrate the co-existence of the typical
Upper Old Red Sandstone fauna with that of the Carboniferous
Limestone. The red or lower division of the Calciferous Sandstone
Series is therefore no longer united to the upper or grey division,
but is grouped with the underlying and lithologically similar forma-
tion of the Upper Old Red Sandstone.

This change we believe to be wholly uncalled for, especially in
the present stage of the Devonian controversy, when every step
should be made with the greatest circumspection. All who have
interested themselves in this question are well aware that in the
south-west of Ireland, the Upper Old Red Sandstones are separated
from the lowest Carboniferous Limestones by the enormous mass of
the Coomhoola Series and the Lower Limestone Shales. These
rapidly thin out as we proceed to the north, until the Carboniferous
Limestone rests at once upon Silurian rocks. Still further to the
north the Limestone itself is divided into an upper and lower
portion by the intercalation of the sandstone beds of the Calp.
Almost upon the same parallel the interesting researches of Mr.
Goodchild have made it evident that the Carboniferous Limestone of
Westmorland is similarly divided into an Upper and Lower portion
by the gradual intercalation of the Ash Fell Sandstones, etc., with
a few calcareous bands. The arenaceous rocks thicken out as we
pass northward to Cross Fell, while the underlying lower portion of
the Carboniferous Limestone simultaneously thins away till the

Reviews—Prof. Geikie’s Geological Map of Scotland. 183

arenaceous rocks rest immediately upon the Silurians. The Scottish
Calciferous Sandstones are admitted to be actually the northerly
extension and expansion of these red and grey sandstones of
Westmorland. In other words, they are simply arenaceous repre-
sentatives of the Lower or central portion of the English Carbo-
niferous Limestone. The greater abundance of these coloured
sandstones in the Carboniferous rocks of Arran is in exact corre-
spondence with the general behaviour of the strata of this system in
Britain generally ; and the presence of the Carboniferous Limestone
fossils, even in their very lowest beds, instead of being matter for
astonishment, and an argument for a local revolution in our present
plan of classification, is, on the other hand, so natural and inevitable
under our present ideas of the relationships of the Upper Old Red
and the Carboniferous, that, from an a priori point of view, it is almost
impossible to conceive how the facts should have been otherwise.

Of the Carboniferous formation itself, four divisions are noted by
the author—the Calciferous Sandstones, the Carboniferous Lime-
stone, the Millstone Grit, and the Coal-measures. The first of these,
under the arrangement already described, includes only the Upper
or Cement-stone division of the original Calciferous rocks. The
limits of these sub-groups are accurately traced through the whole
of the Central Valley. The disputed coal-field of Canobie is fixed
as belonging to the true Coal-measures, and the wide sheet of Car-
boniferous rocks in Eskdale, etc., has been removed to the Calci-
ferous Sandstones.

The Permian areas of Annan, Dumfries, Thornhill and Moffat,
have now for the first time their limits correctly laid down. No
alteration is made in the outline of the Triassic district in the neigh-
bourhood of Elgin; but the small patch of rocks of this age dis-
covered by Professor Judd near Dunrobin is indicated upon the
map, and the complete dissipation of the doubts regarding the
actual presence of this formation in Scotland is distinctly acknow-
ledged in the removal of the note of interrogation from its title in
the margin.

Indeed, the masterly papers of Professor Judd have proved a mine
of wealth to the author. As far as possible all the more important
details worked out by him are here inserted. The Jurassics of
Sutherland and the Western Isles are coloured in two divisions ; the
Cretaceous rocks find for the first time in the map of Scotland
their special place and colour; and the geological structure of the
volcanic region of Mull and the adjacent coasts is delineated with a
minuteness and clearness, which, when we consider the small scale
of the map, is almost marvellous.

Glacial and post-Tertiary geology generally comes in for a full
share of attention. Over the whole country are arrows showing the
local direction of the glacial striz. The main streams of glacial
debris and morainic matter are dotted in over the Lowlands, and
upon both flanks of the Grampian range. The raised beach, the
fertile carse of alluvium and the barren tract of blown sand, are
separately indicated, each by its special and appropriate shade of
colour.

134 Reports and Proceedings— Geologists’ Association.

Tn point of execution and finish the marginal sections are de-
ciledly inferior to the main body of the map. They are six in
number, and illustrate the geological structure of the Highlands,
Forfar, the Southern Uplands, the Midland Valley, and the Volcanic
Region of Mull and Morven.

The igneous rocks have been laid down with special care. They
are distinguished by a separate type of colour according as they
belong either to the acidic or pyroxenic and basic series; the main
species of each group being separated by variations in depth of
tint. Much advance has also been made in their chronological
arrangement. The main geographical masses, whose age has been
satisfactorily determined, are marked upon the map by the letter or
figure significant of the epoch to which they belong. The outlines
of the chief granitic areas of the Uplands and Highlands are
corrected ; but although the author has elsewhere shown that there is
a high probability that they are of Old Red age, he has wisely
refrained from fixing their systematic position upon the map. The
ring of igneous rock which surrounds the great Valley of Central
Scotland is now lettered as being composed of two portions of very
different ages. The Pentlands and Ochils belong to the Old Red
Sandstone, while the Campsie Fells and the hills of Renfrew and
Cunningham are classed with the Lower Carboniferous. The Cheviot
porphyries are correctly mapped for the first time, and are definitely
assigned to the earlier of these epochs. The main sheets of igneous
rock among the Upper Old Red beds of Roxburgh are inserted,
and the peculiar amygdaloidal trap which lies at the base of the
Carboniferous Sandstones of Riccarton, is traced continuously from
the northern flanks of the Cheviots into the well-known igneous
mass of Barnswark in Annandale.

Of the thorough correctness of the geological portion of the map
we can speak with perfect confidence, as it has been our faithful
companion in many a geological excursion, not only. in the well-
known beds of the Central valley, but also among the more enigma-
tical strata of the Uplands and Highlands, and we have invariably
found it correct.

In the multiplicity of its detail, in the conscientious accuracy of
its workmanship, and in its fitness for the special purpose it is in-
tended to subserve, this map is unique in its class. It is creditable
alike to its author and to its publisher, and is simply invaluable to
those who wish to possess an accurate knowledge of the geological
structure of Scotland. C. Lapworru.

RHEPORTS AND PROCHHDINGS.-
suis gles
Tur Grotocists’ Association.—At a meeting held at University
College on the 4th January last, Mr. H. Goss, F.LS., F.G.S., ete.,
communicated a paper on “The Insect Fauna of the Secondary or
Mesozoic Period, and the British and Foreign Strata in which
Tnsect-remains have been detected.” After making some intro-
ductory observations and calling attention to the writings and in-

Reports and Proceedings—Geologists’ Association. 135

vestigations in the United Kingdom of Dr. Henry Woodward, F.R.S.,
the Rev. P. B. Brodie, Prof. Westwood, the Rev. Osmond Fisher, and
others, Mr. Goss observed that the majority of the fossil insects from
British strata of the Secondary period had been obtained from
the Upper Oolite (Purbecks) and from the Lias, and that nearly all
the Huropean specimens had been discovered in the Solenhofen slate
of Bavaria, or in the Lias of the Swiss Alps. Allusion was made to
the difference in the state of preservation of insects from British
strata of this period as compared with that of those from the Solen-
hofen slate, and the probable reasons for this difference in the state
of preservation were stated. The names of the principal discoverers
and students of fossil insects from Secondary rocks on the Con-
tinent of Europe, including those of Professor Germar, Count
Miinster, Dr. Hagen, Professor Heer, Dr. Giebel, etc., were then
mentioned, and Mr. S. H. Scudder was referred to as the chief
worker in America.

The various strata of this period, both in the United Kingdom
and on the Continents of Europe and America, in which fossil
insects had been detected, were then enumerated in the descending
order of geological succession.

It appeared that a few insect-remains had been obtained from the
Weald Clay and Hastings Sands, and a great number from the
Purbeck strata of Dorsetshire, Wiltshire, and Buckinghamshire,
especially from those of the first-named county. The species which
had been identified belonged to the orders Coleoptera, Orthoptera,
Neuroptera, Hemiptera, Diptera and Hymenoptera, and more than
half of those from the Dorset Purbecks belonged to the first-named
order. The Purbeck species appear as a rule to be closely allied to
existing forms, and the small size of the majority of them was, in
the opinion of Professor Westwood, indicative of a temperate climate ;
but from the nature of the remains of other orders of animals, and
of the plants from these strata, the prevalence of such a climate
during this period seemed improbable.

A few Elytra of Coleoptera were recorded from the Kimmeridge
Clay, the Forest Marble and the Great Oolite, and the remains of
one insect, which Professor Westwood thought might be referred to
a larva of Libellula, had been found in the Oxford Clay. The
remains from the Stonesfield slate were principally Hlytra of Coleo-
ptera, but they also included a few Newroptera and two doubtful
specimens of Lepidoptera. One of the supposed Lepidoptera (which
had been described and figured by Mr. A. G. Butler, and named by
him Palgontina Oolitica) was considered by Mr. Scudder to be
Homopterous rather than Lepidopterous, and allied to Cicada.

A great quantity of insect-remains had been obtained from the
Lias and Rheetics, but they were generally in such a fragmentary
condition that the bulk of them could not be identified. About 56
species had been determined, and they had been referred by West-
wood and Brodie to the orders Coleoptera (29 species), Neuroptera
(12 species), Orthoptera (7 species), Hemiptera (6 species), and
Diptera (2 species) ; but no traces of Hymenoptera or Lepidoptera

136 Reports and Proceedings—

had been met with, and the remains referred to the Diptera were
very doubtful.

The Lias insects, although apparently belonging from their size
to a temperate climate, differed from those from Purbeck strata in
being less closely allied to European forms, and approaching nearer
to those now inhabiting North America.

On the Continent of Europe a few remains of insects, which had
been referred to Carabide and Curculionide, had been obtained from
the Cretaceous strata in the neighbourhood of Aix-la-Chapelle, and
a few traces of insects had also been noticed by Dr. Geinitz in the
Greensands of Saxony.

Attention was then drawn to the remains from the Solenhofen
slate, which had been referred by Germar, Miinster, Hagen and
Giebel to insects belonging to the orders Coleoptera, Orthoptera,
Neuroptera, Hymenoptera, Hemiptera, Lepidoptera and Diptera. The
order Neuroptera appeared better represented than any other, and
comprised many gigantic species, most of which were referred by
Hagen to extinct genera, though some of them were allied to exist-
ing American and Australian species.

From the Lias of Shambelen in the Swiss Alps about 2000
specimens had been obtained by Professor Heer, which comprised
145 species, 116 of which he had referred to Coleoptera, 7 to
Orthoptera, 7 to Neuroptera, 12 to Hemiptera, and 1 to Hymenoptera.
The majority of the insects from the Swiss Lias were small like
those from British strata of the same period.

Only five insects appeared to have been found in Huropean
Triassic rocks, viz. two species from the Keuper of Vadutz and
three species from the Bunter Sandstein! of Trebitz and Salzmunde.
In conclusion, allusion was made to certain traces of insects in the
Trias of the Connecticut Valley (North America) which had been
referred to by Mr. 8. H. Scudder.

GroLocicaL Society or Lonpon.—I.—January 9, 1878.—Prof.
P. Martin Duncan, M.B., F.R.S., President, in the Chair.—The
following communications were read :—

1. “On the Great Flat Lode south of Redruth and Camborne.”
By Dr. C. Le Neve Foster, B.A., F.G.8.

The author described the mode of occurrence of the stanniferous
deposit known as the Great Flat Lode, the mines worked in which
extend for a distance of 34 miles, and furnish about one-eighth of
all the tin raised in Cornwall. The mines in question are Wheal
Uny, South Carn Brea, West Wheal Basset, South and West Wheal
Frances, South Condurrow, and Wheal Grenville; and in all the
lode dips at a much less angle than the average of Cornish veins,
the dip at Wheal Uny being only about 46° 8. Throughout the
lode contains a small leader, usually only a few inches wide,
occupying the space due to the shifting of the two sides of a
fissure, and filled partly mechanically, partly chemically. Above or
below, or on both sides of this, there is a mass of stanniferous schorl

1 Vierteljahrsschrift der Naturforschenden Gesellschaft in Zurich, Viertes Heft,
p- 297, and Heer’s Urwelt der Schweiz.

Geological Society of London. 137

rock from 4 to 15 feet wide; this contains from-1 to 8 per cent. of
cassiterite, in little grains, or in strings or veins. Schorl rock, very
poor in tin (locally called capel or greyback), separates the lode
from the surrounding granite or killas, but passes on one side into
the lode, and on the other into the granite or killas, so that no wall
is recognizable. From these characters the author inferred that the
lode and the capel are merely altered rocks, the fissure now occupied
by the leader having served to bring up vapours or solutions which
have entirely changed the rocks on both sides of it. In support
of his opinion, the author adduced other instances of the change of
both granite and killas into schorl rock; and further stated that,
both at South Condurrow and Wheal Grenville, he has found in the
schorl rock cavities as large as a pea, agreeing in form with crystals
of orthoclase felspar.

2. “On some Vin-mines in the Parish of Wendron, Cornwall.”
By Dr. C. Le Neve Foster, B.A., F.G.S.

The mines described in this paper are called Balmynheer, the
Lovell, and South Wendron. In the former the stanniferous deposit
consists of a large irregular mass of rock 30-50 feet thick; its
dip is N., at an angle of about 30°, and its strike H. 32° N., along
which it has been traced for 36 fathoms. The tinny rock is separated
from the granite above by a slide dr vein of white clay, with a
little quartz and mica, about 6 inches thick, but passes insensibly
into the granite below. At the Lovell Mine there are two lodes,
north and south, the former striking from 87° to 45° N. of E. and
dipping N.W. at an angle of about 70°, the latter running EH. 48° N.
and dipping N.N.W. about 60°, so that the two lodes unite in going
eastward and in depth. The lode is separated on one or both sides
from the adjoining granite by a rock locally known as “cab,” 6-12
inches thick, composed of quartz, mica, gilbertite, chlorite, iron
pyrites, copper pyrites, and a little schorl. The lode itself shows
joints which are mere planes of division in the rock, and usually
have the same strike and dip ; divergent joints also occur, and where
these traverse the granite, they carry with them a little tin-stuff for
some distance. The South Wendron Mine is worked in an irregu-
larly cylindroid pipe of tinny rock, merging gradually on all sides
into the granite ; the shorter axis of its oval section is about 10 feet,
while the longer axis varies from 20 to 60 feet. It dips at an angle
of 49° in a direction N. 25° W. The stanniferous rock in these mines
is essentially a mixture of quartz, chlorite, gilbertite, iron pyrites,
and tin-ore, with zinc-blende in some cases, and usually some mica;
fine needles of tourmaline occur in the cavities which it incloses.
In the South Wendron Mine the southern part of the pipe is some-
times very granite-like in appearance, consisting of pink orthoclase
crystals imbedded in a mass of quartz, chlorite, mica, and iron
pyrites, with a little copper pyrites, fluor, and tin-ore. One specimen
is a true stanniferous granite. These characters lead the author to
the same conclusion he has arrived at in the case of the Great Flat
Lode, namely, that these tin deposits consist entirely of altered
granite, and are not ordinary mineral veins; they have no walls,

138 Reports and Proceedings—

but the stanniferous rock passes gradually into granite; and they
show no signs of banded structure due to the successive deposition
of minerals. The highly granitic character of part of the South
Wendron tin deposit is strongly confirmatory of this view, which is
further supported by the occurrence, in the dark mass of the so-
called lode at the Lovell, of pseudomorphs of quartz after orthoclase
containing a little cassiterite.

3. “On some of the Stockworks of Cornwall.” By Dr. C. Le
Neve Foster, B.A., F.G.S.

The author commenced by explaining that the term “Stockwork”
had been derived from the German Stockwerck, meaning “ Storey-
work,” in allusion to the method of working in steps or storeys
in open workings originally adopted for such deposits. Their being
worked in open quarries affords a good opportunity of studying the
mode of occurrence of tin; and many of them are interesting on
account of the small percentage of tin which will cover all expenses.
Thus, in the Wheal Prosper Mine, the average amount of oxide of
tin obtained per ton of stuff is not more than 3 lbs., worth, at the
present price of “black tin,” 44d. per lb., so that the ground as it
stands is only worth 133d. per ton. The mine can be worked
without loss on account of the softness of the rock and the large
size of the grains of tin-ore, the comparative lightness of the sub-
stances associated with it, and the command of water-power.

The deposits worked as Stockworks occur in Cornwall in killas,
granite, and elvans. The tin-ore, associated with quartz and with
small quantities of other minerals, is found in more or less parallel
thin veins and strings, dipping at a high angle, and occasionally
giving off branches or uniting with one another both in dip and
strike. In the killas the rock close to the veins is occasionally
altered into tourmaline schist ; in the granite the walls of the veins,
and sometimes the whole mass of granite, are altered into greisen
and schorl rock. At Carclaze the orthoclase of the intervening bands
of granite has been converted into china clay, which is now the main
object of the working. At Carrigan the leader sometimes adheres
to the inclosing rock by one side only, the other being bounded by
a clay vein which contains broken crystals of cassiterite, indicating,
in the author’s opinion, that a movement of the walls has taken
place since the deposition of the tin-ore. Of the Stockworks in elvans
the author gave a list, and remarked that the elvan of the Terras
Mine is particularly interesting, as it presents a series of cavities
left by the removal of orthoclase, and now being filled up with
schorl and a little oxide of tin.

4. “The Precarboniferous Rocks of Charnwood Forest.” Part II.
By the Rev. E. Hill, F.G.S., Fellow and Tutor, and the Rev. Prof.
T. G. Bonney, F.G.S., Fellow and late Tutor of St. John’s College,
Cambridge.

The authors described the result of the microscopic examination of
a considerable series of the clastic rocks of Charnwood. Many of
these, even among the finer beds, prove to be of pyroclastic origin.
The coarser are generally composed of a ground mass of pulverized

Geological Society of London. 139

felspar, with viridite and some iron peroxide, full of larger frag-
ments of felspar crystals (generally both of orthoclase and plagio-
clase) and lapilli. The structure of these is often distinct, some are
certainly andesites, others some kind of trachyte; slaty fragments
are also present, and occasional grains of quartz. The authors
express their opinion that all the larger felspar crystals, and most,
if not all, the quartz grains, are of clastic origin, even in the more
highly altered varieties. Some of the larger fragments in the
breccias were examined, and referred in part to devitrified trachytes
not very rich in silica. The igneous rocks were then described.
The syenites of the southern and northern districts were shown
probably to, belong to one system of intrusion. The hornblendic
granite of the Quornden district was also described, and the micro-
scopic structure of the different varieties of it and the above inves-
tigated. A number of igneous rocks generally forming dykes in
these was described; some appear to be altered basalts, others
andesites, one is a felsite, another a diorite. A group of outlying
igneous rocks in the vicinity of Narborough was described. Of
these, one is a quartz felsite with some hornblende; another varies
between this and a quartziferous syenite ; the rest are syenites, and
one contains so much plagioclase as to be almost a diorite. One of
the above, near Enderby, is seen to be distinctly intrusive in an
altered slaty rock, which the authors have no doubt belongs to the
Forest series. This discovery proves the igneous character of these
rocks also, and extends the area of the slaty series five miles further
south than was previously known. A section was devoted to the
faults of the Forest region. Here the principal fault runs along the
anticlinal axis, with a downthrow on its eastern side which di-
minishes from 2500 feet at the north end to 500 feet at the south
end. Hast of this the beds seem undisturbed, but on the west they
are shattered by many faults, whose course cannot be traced. These
are most numerous near Whitwick. The anticlinal fault is Precar-
boniferous.

In conclusion, the age of the clastic and of the igneous rocks was
discussed. The authors inclined to the opinion that the former are
of the same age as the Borrowdale series of the Lake-district
(Lower Silurian), but admitted that the recent discovery of agglo-
merates in the Precambriam rocks of Wales, and in the probably
Precambrian ridges of the Wrekin district, weakens the arguments
for this correlation. They do not think that there is any reason for
supposing them Cambrian. If the Charnwood series is Lower
Silurian, they think it most probable that the syenites and the
Quornden granite were intruded in some part of the Old Red Sand-
stone period, and that the later dykes were very probably Postcar-
boniferous but Pretriassic.

Il.—January 23, 1878.—Prof. P. Martin Duncan, M.B., F.R.S.,
President, in the Chair.—The following communication was read :—

“On the Secondary Rocks of Scotland. Part III. The Strata of
the Western Coast and Islands.” By John W. Judd, Esq., F.RB.S.,
F.G.8., Professor of Geology in the Royal School of Mines.

140 Reports and Proceedings—

The existence of scattered patches of fossiliferous strata, lying be-
tween the old gneissic rocks and the masses of Tertiary lava in the
Hebrides has been known to geologists for more than a century.
By Dr. Macculloch, who did so much for the elucidation of the in-
teresting district in which they occur, these strata were referred to
the Lias; but Sir Roderick Murchison showed that several members
of the Oolitic series were also represented among them. Later
researches have added much to our knowledge of the more accessible
of these isolated patches of Jurassic rocks in the Western Highlands.

During the seven years in which he has been engaged in the study
of these interesting deposits, the author of the present memoir has
been able to prove that not only is the Jurassic system very com-
pletely represented in the Western Highlands, but that associated
with it are other deposits representing the Carboniferous, Poikilitic
(Permian and Trias) and Cretaceous deposits, the existence of which
in this area had not hitherto been suspected; and by piecing to-
gether all the fragments of evidence, he is enabled to show that
they belong to a great series of formations, of which the total
maximum thickness could have been little, if anything, short of a
mile.

The relations of the scattered patches of Mesozoic strata to the
older and newer formations respectively are of the most interesting
and often startling character. Sometimes the Secondary rocks are
found to have been let down by faults, which have placed them
thousands of feet below their original situations in the midst of
more ancient masses of much harder character. More usually they
are found to be buried under many hundreds, or even thousands of
feet of Tertiary lavas, or are seen to have been caught up and in-
closed between great intrusive rock-masses belonging to the same
period as the superincumbent volcanic rocks. Occasionally the only
evidence which can be obtained concerning them is derived from
fragments originally torn from the sides of Tertiary volcanic vents,
and now found buried in the ruined cinder-cones which mark the
sites of those vents. In some cases the mineral characters of the
strata have been greatly altered, while their fossils have been occa-
sionally wholly obliterated by the action of these same igneous forces
during Tertiary times.

In every case the survival to the present day of the patches of
Secondary rocks can be shown to be due to a combination of most
remarkable accidents: and a study of the distribution of the frag-
ments shows that the formations to which they belong originally
covered an area having a length of 120 miles from N. to 8., anda
breadth of 50 miles from H. to W. But it is impossible to doubt
the former continuity of these Secondary deposits of the Hebrides
with those of Sutherland to the north-east, with those of Antrim to
the south, and with those of England to the south-east. From the
present positions of the isolated fragments of the Mesozoic rocks,
and after a careful study of the causes to which they have owed
their escape from total removal by denudation, the author concludes
that the greater portion of the British Islands must have once been

Geological Society of London. 141

covered with thousands of feet of Secondary deposits. Hence it
appears that an enormous amount of denudation has gone on in the
Highlands during Tertiary times, and that the present features of
the area must have been, speaking geologically, of comparatively
recent production—most of them, indeed, appearing to be referable
to the Pliocene epoch.

The alternation of estuarine with marine conditions, which had,
on a former occasion, been proved to constitute so marked a feature
in the Jurassic deposits of the Eastern Highlands, is now shown to
be almost equally striking in the Western area; and it is moreover
pointed out that the same evidence of the proximity of an old shore-
line is exhibited by the series of Cretaceous strata in the West.

The succession and relations to one another of the series of de-
posits, now described as occurring in the Western Highlands, is
-given in the following Table :—

Miocene Volcanic and Intervolcanie Rocks.

U. Maximum
NCONFORMITY. thicknesses.
feet.
2 1, Estuarine clays and sands with coal... co co 20
3 | 2. White Chalk with flints (Zone of Belemnitella muer weronata) ong 10-+-
sg 4 3. Estuarine Sandstones with coal... oa oo OO
oanes (inmate Careemsninol G0 ces. non cod on Sco, 60
ol
UnNconrorMIry.
( 5. Oxfordclay ... Sie) Red SeB: Goons) pode.) 602 8 bod’ 600! 660 ?
GN Greatphistuarine)Seriesh Meualegins (ie cnn ieyentilinits Laue B00
S | We leaner Olle 857 en6 coe 600) eee! cao ceo ono! 0p) cco cco, AOD)
bie ee Sug pera lidas 4 Victk' posuere eee iass ate ech uy toon eens) LOO
Snipa OuNddietias | ee Me rn Umer nN mn Re nag
Ee OM owerslias: etc 1 ca tena) seeey Desc n Leen Nove iiccet gic soulnenstetasee erL00
| Il, TmbrANeIS 66) 695+ 009° x60 doa. doo. 080..-0b0, a0, odo", tong, cng. 1) AOD
(CHP TEOUSUMHC A056 oto chock oc cto, cto) cd cod coo! (G00) INOS

UNcONFORMITY ?

Carboniferous strata (Coal-measures).

UNcONFORMITY.
Old Gneiss Series and Torridon Sandstones.

Although no traces of the Upper Oolite or the Neocomian forma-
tions have as yet been detected in the Western Highlands, yet it is
argued that when we consider how enormous has been the amount
of denudation, and how singular the accidents to which all the ex-
isting relics of the Secondary period have owed their escape from
total destruction, we cannot but regard it as a most rash and
unwatrrantable inference to conclude that no deposits belonging to
those periods were ever accumulated within the district under con-
sideration.

The Carboniferous strata of the Western Highlands have been
detected at but a single locality; and even there, being exposed in
a series of shore reefs that are only occasionally well displayed,
can only be studied under favourable conditions of tide and wind.

142 Reports and Proceedings—

They consist of sandstones and shales with thin coaly seams, and
their age is placed beyond question by the discovery in them of
many well-known plants of the Coal-measures, including species of
Lepidodendron, Calamites, Sigillaria, and Stigmaria.

The Poikilitic strata consist of conglomerates and breccias at the
base, graduating upwards into red marls and variegated sandstone,
which contain concretionary limestones and occasional bands of
gypsum. ‘These strata have not as yet, like their equivalents in the
Eastern Highlands (the Reptiliferous Sandstone of Elgin and the
Stotfield rock), yielded any vertebrate remains. They were evi-
dently deposited under similar conditions with the beds of the same
age in Hngland, and are not improbably of lacustrine origin.

The Jurassic series presents many features of very great interest.
The Infralias is better developed than is perhaps the case in any part
of the British Islands; and in the district of Applecross a series of
estuarine beds, containing thin coal-seams, is found to be intercalated
with the marine strata.

The Lower Lias, in its southern exposures, presents the most
striking agreement with the equivalent strata in England, but when
traced northwards exhibits evidence of having been deposited under
more littoral conditions; the lower division (Lias a, Quenstedt) is
represented by a great thickness of strata ; while the upper (Lias @)
is absent or rudimentary. The Middle Lias is grandly developed,
and consists of a lower argillaceous member and an upper arenaceous
one, the united thickness of which is not less than 500 feet.
The Upper Lias singularly resembles in the succession of its
beds, and its paleontological characters, the same formation in
England. The Inferior Oolite is formed by series of strata varying
greatly in character within short distances, and betraying sufficient
signs of having been accumulated under shallow-water conditions.
Above the Inferior Oolite we find a grand series of estuarine strata,
partly arenaceous and partly calcareo-argillaceous ; and this is in
turn covered conformably by an unknown thickness of blue clays
with marine fossils of Middle Oxfordian age. At the very lowest
estimate, the Jurassic series of the Western Highlands could not
have had a thickness of less than 3000 feet !

The Cretaceous strata of the Western Highlands, though of no
great thickness, are of surpassing interest. They consist of two
marine series alternating with two others of estuarine origin. At
the base we find marine deposits of Upper Greensand age, strikingly
similar to those of Antrim, but in places passing into conglomerates
along old shore-lines. Above the Upper Greensand beds occur un-
fossiliferous sandstones, in which thin coal-seams have been detected,
and these are in turn covered by strata of chalk, converted into
a siliceous rock, but still retaining in its casts of fossils (Belemnitella,
Tnoceramus, Spondylus, etc.), and in its beautifully preserved micro-
scopic organisms (Foraminifera, Xanthidia, etc.), unmistakable proofs
of its age, and the conditions of its deposition. Above this repre-
sentative of the highest member of the English Chalk there occur
argillaceous strata with coal-seams and plant-remains which are

Correspondence—Ur. T. Mellard Reade. 143

perhaps the equivalent of younger members of the Cretaceous series,
not elsewhere found in our islands, or, it may be, they must be
regarded as belonging to periods intermediate between the Cretaceous
and Tertiary epochs. It is greatly to be regretted that these Cre-
taceous deposits of the Western Highlands are so unfavourably
displayed for our study as to present scarcely any facilities for the
collection of their fossils; for these, if found, might be expected to
throw a flood of light on some of the most obscure paleontological
problems of the present day.

Although the comparison and correlation of the Secondary strata
of the Highlands with those of other areas, and the discussion of the
questions of ancient Physical Geography thereby suggested, are
reserved for the fourth and concluding part of his memoir, the author
takes the opportunity of making reference, in bringing the present
section of his work to a close, to several problems on which the
phenomena now described appear to throw important light. In
opposition to a recent speculation which would bring into actual
continuity the present bed of the Atlantic and the old Chalk strata
of our island, he points to the estuarine strata of the Hebrides as
demonstrating the presence of land in that area during the Cretaceous
epoch. He also remarks on the singular agreement of the conditions
of deposition of both the Silurian and Cretaceous strata of the
Scottish Highiands and those of the North American Continent.
But he more especially insists on the proofs, which we now have,
that the Highlands of Scotland, as well as the greater part of the
remainder of the British Islands, were once covered by great deposits
of Secondary strata, and that the area has been subjected to enor-
mous and oft-repeated denudation. He dwells on the evidence of
the vast quantities of material which have been removed subse-
quently to the Mesozoic and even to the Miocene period, and he
maintains the conclusion that many, if not all, of the great surface-
features of the Highlands must have been produced during the very
latest division of the Tertiary epoch, namely the Pliocene.

CORRS = @iNeD aN Ca.

——
INDUCED STRUCTURE IN STONE.

Srr,—A very remarkable exfoliated piece of sandstone from an
urn forming part of a tombstone was brought me by a mason a
short time ago. It is from the base or pillar of the urn itself, and
measures 9in. by 5in., varying in thickness from +¢ to ~> of an
inch. The outside surface had been worked and rubbed in forming
the urn, and one side of the exfoliated piece consists of this worked
surface perfectly preserved. The pedestal has a horizontal and
vertical curvature, and when laid on the table the exfoliated piece
rises fully two inches in the quickest part of the curve. I exhibited
this specimen at the last meeting of the Liverpool Geological
Society, when some scepticism was evinced as to its being genuine

144 Miscellaneous—WMarine Fossils in Gannister Beds.

sandstone. JI have since examined the tombstone, which is in St.
James’s Cemetery, and find that it is genuine stratified sandstone,
which the microscope had before proved. It is of extremely fine
grain, and I can detect nothing but minute grains of silex in its
composition. Hydrochloric acid does not affect it. The stone, I am
told, comes from somewhere near Burnley, and it evidently belongs
to the Carboniferous group. The bedding of the stone in the base
of the tomb shows in rusty iron streaks, and exposure discolours it
in places. I have since receiving the specimen, on visiting Canter-
bury Cathedral, noticed that the surface of the Purbeck marble
shafts inside the choir exfoliate, following the worked surface, but
not nearly in so regular a manner as indeed we would anticipate
from its fossil structure.

It appeared to me very remarkable that the exfoliation should
follow so truly the worked surface of the stone, only varying
the 31+ of an inch, especially in the case of a bedded sedimentary
rock, instead of following the planes of bedding as is usually the
case. JI am informed it was customary to oil the stones in this
Cemetery with a view to their preservation. Can this have effected
it? Ican find no trace of oil in it now.

T. Metiarp READE.

Park CorNER, BLUNDELLSANDS.

Norr.—A<s bearing upon the above letter, we may state that Prof. Morris has for
twenty years been accustomed to direct the attention of geological students to the
curious molecular change produced by ‘dressing’’ stone, whether for architecture
or statuary. From his careful observations it would appear that most compact
stones when “dressed”? seem less disposed to follow their original inclination to
break up along certain planes, and exhibit a stronger tendency to exfoliate in layers
parallel to the artificially-worked surface of the stone. One of his favourite illus-
trations was a gigantic arm of syenite or red granite, once forming part of a colossal
statue of Thothmes III., discovered by Belzoni in 1818, lying in the sand in the
Karnak quarter of Thebes. This arm, which now forms one of the most striking
objects in the Egyptian Gallery of the British Museum, exhibits near the shoulder
a tendency to exfoliate in regular concentric layers corresponding with the worked
and polished surface of the limb. Mr. Mellard Reade will, we feel sure, be pleased
to find that his idea of the “ induced structure in stone” has the support of so dis-
tinguished an authority as that of Professor Morris.—Epir. Grou. Mac.

VERS Cae A IW HOuUS-

Marine Fossins in THE ‘GANNISTER Beps.”— Mr. G. A. Lebour,
writing from the College of Physical Science, Newcastle-on-Tyne,
to “ Nature,” announces the discovery (on the 9th Feb.) of marine
fossils in the Lower Coal-measures or “Gannister beds” of North-
umberland between Stocksfield Station and Whittonstall. Hitherto
no marine forms had been found in this series.

Acapremic Honour.—At a congregation of the Senatus Acade-
micus of the University of St. Andrews, on Saturday, February 9th,

the honorary degree of LL.D. was conferred on Henry Woodward,
F.R.S., F.G.S., of the British Museum.

THE

GEOLOGICAL MAGAZINE.

NEW SERIES! DECADE Wh VOL.
No. IV.—APRIL, 1878.

Ore GaN eo Assay eAeting ole als @ see SS

—=<

T.—Tue Acre or THE WorRLD AS VIEWED BY THE GxroLoaIst
AND THE MATHEMATICIAN.

By T. Metiarp Reapg, C.E., F.G.S.

NTIL Geology began to take the place of a science, few, if any,

troubled themselves about the age of our planet. The habit

of thought, created partially by the Mosaic Cosmogony, which led

us to look at all the natural features around us,as if but just freshly

formed by the hands of the Creator was not favourable to any such
inquiry.

To think that everything, as we see it now, is as it always was,
is easy and natural, saves trouble, and is a habit of mind deeply en-
grained in human nature. It is only within the last few years that
we have been able to dispossess ourselves of this notion with regard
to animated nature. Special creation of everything as we see it
answers best to our anthropomorphic ideas, derived from a contem-
plation of man’s creative efforts. The conception of innate energy,
continuity, and evolution, is a higher stage of thought, only arrived
at by close observation of, and reasoning on, the relations of natural
phenomena. .

So far as my knowledge of history extends, the geologist was the
first to raise the question of the Earth’s age. Astronomy did not
lead to its contemplation. No one that I am aware of, before geolo-
gical inquiry, said the Earth must be so many millions of years old,
because the rate at which the temperature increases downwards
shows that it must at least have taken so long to cool from the time
when it was an incandescent globe. Yet it is the astronomer who
inferred long since that this Harth of ours, from its spheroidal form,
must originally have been in a molten state, and the same elements
existed at the time for the calculation of its age from a physical
basis that do now. Why then was it not done? Simply because it
did not strike any one that it must be extremely ancient, as the
evidences of age did not come prominently forward.

When, however, the curiosity of the geologist, delving into the
Harth’s crust brought to light the fact that under thousands of feet
of rock lay the evidences of the existence, at an earlier period, of a
fauna and flora differing from those of the present day,—of rivers,
seas and continents now buried below deposits to which those
obscuring the remains of ancient Troy are as a film of dust,—it was
impossible any longer to resist the conviction that the age of the

DECADE II.—VOL. V.—NO. IV. 10

146 T. Mellard Reade—The Age of the World.

world was enormously greater than any one had before contem-
plated.

So averse, however, is the human mind to receive new impres-
sions, that the first geologists had to shorten the life of the world
by periodical convulsions and the assumption of more potent
natural causes in the earlier periods of the Harth’s history.

In this again they were assisted by another vice of the mind—
that of generalizing from small data. Faults, foldmgs of the strata,
and other evidences of former volcanic activity, that have been
since proved to be only local phenomena, were assumed to have
extended all over the Harth at the same time, and to have separated
its history into “periods.” This I call constructive geology, due to
an unscientific use of the imagination. Yet those crude and hasty
generalizations were not to be wondered at; for the peculiar scientific
habit of thought engendered by sound geological reasoning had not
then been acquired.

To Hutton is due the merit of placing geological investigation on
a sound basis, and to Lyell philosophical geology almost owes its
existence.

The conception of the possibility of explaining all the phenomena
of the Harth’s crust by agencies at present at work, lies at the
foundation of all geological reasoning. It is one, however, that does
not necessarily commend itself to the judgment at first sight,
because there are no a-priort improbabilities in conceiving that
agencies may have been at work at former periods of which we
now know nothing. If, however, we attentively study the Harth’s
crust, we become gradually convinced that the agencies we are
acquainted with are competent to explain all the complicated phe-
nomena with which it abounds, and not only so, but that no other
agencies can satisfactorily explain them.

Therefore, instead of a playful exercise of fancy, we begin our
investigations on a sure foundation—so sure indeed that no geologist,
so far as I am aware, has been compelled to adopt any other hypo-
thesis, though of course different opinions are held with regard to
the relative activity of these forces at various stages of the history of
the Earth.

Geology, then, is a pre-eminently practical common-sense science,
because it is always testing its conclusions by reference to the Harth
itself. The reasoning is essentially of an inductive cast. It is
necessarily a safe science, for it cannot get far on the wrong road
without being set right. Astronomy is a more exact science ; the
relations it sets itself to investigate are simple ones—mechanical
conceptions capable of mathematical demonstration and verification
by exact measurement. When I say the relations it investigates
are simple, I say it with the profoundest respect; for the solutions of
some of these problems are among the greatest triumphs of the
human mind. The method of procedure is, however, essentially
different, and the attempt to displace the geological by the me-
chanical method in developing the geological history of the Harth
is, 1 trust to be able to show, one not likely to succeed.

T. Mellard Reade—The Age of the World. 147

To Sir Wm. Thomson is due the merit of first attempting to
apply the physical, or what I prefer to call the mechanical method,
to the determination of the age of the Harth. Three ways have
been suggested by him for doing this; but it is only to the one on
which he most relies—founded on the increase of temperature
proved by experiment to take place from the surface downwards—
that I propose to refer. The calculation is based upon the assump-
tion that the whole mass of the Harth was at one moment at an
incandescent heat estimated at 7000° Fahr. warmer than our present
surface temperature; that it was at an initial moment at this
uniform temperature throughout, from which time it has since been
uniformly cooling through being exposed to the present surface
temperature. By a mathematical process, the experimental elements
of which depend upon the average thermal conductivity of the
materials of the Harth, and the average augmentation of heat down-
wards, he arrives at the conclusion that it is improbable more than
100 millions of years have elapsed since the surface of our globe
became habitable.

Now the geologist neither denies nor affirms that the Earth was
once an incandescent mass. By analogy it is probable at the present
time the heat goes on increasing downwards until incandescent
matter is reached: but it cannot be experimentally proved; though
volcanic action now existing in various parts of its surface points to
the same conclusion. It is also not an improbable further deduction
that at one time the globe was incandescent from the centre to the
surface. Arguing from an hypothesis of this nature, and recon-
structing the globe upon it, is what the cosmogonists used to do; but
it is a method alien to geology, which aims at interpreting the his-
tory of the Harth by an examination of its rocks.

Now, for a calculation such as this one suggested by Sir Wm.
Thomson to command assent, it must be based upon very accurate
experiment and observation, that the material points on which it
hinges may be first proved beyond doubt. He says,' “‘ Whatever the
amount of such effects is at any one time, it would go on diminishing
according to the inverse proportion of the square roots of the times
from the initial epoch. Thus, if at 10,000 years we have 2° per
foot of increment below ground,

at 40,000 years we should have 1° per foot
160,000° _,, aby RIAN
4,000,000 oe) oe) To° ”
100,000,000 45 50 | i A

If, therefore, through any error in the calculation, arising from
incorrect inference from experiment, the increment of temperature
should be not 2° but 4° per foot at the end of the first 10,000 years,’
the times would be multiplied fourfold, and would stand thus:

1 Treatise on Natural Philosophy, Thomson and Tait, p. 721.

2 Prof. Helmholtz has calculated, from the rate of cooling of lavas, that the
earth in passing from 2000° to 200° C. must have taken three hundred and jifly
millions of years! Dana, commenting upon this, says: ‘‘ But the temperature when
the Archzan Time (Laurentian and Huronian periods) ended was probably not over
38° C. (100° Fahr.).” Dana’s Manual of Geology, second edition, p. 147.

148 T. Mellard Reade—The Age of the World.

At 40,000 years 2° per foot
160,000 __,, ae 4;
4,000,000 __,, an 55
100,000,000 rou ke 5
AOOOOOOU 6 =
1,600,000,000 Soro

So, if we assume the increment at 1° in 100 feet, and there are to
my mind as good reasons to do so as to assume 1° in 50 feet, the
observations being, as I shall show, so contradictory and inconclusive,
it would in this case bring up the age of the world to 1600 millions
of years. These values may hold good with regard to a homogeneous
mass of uniform conductivity, but not in the case of a globe built
up of strata of varying conductivities. Let us, for example, con-
sider how the effect would be varied in a very simple case.

First, we may assume a globe, the mass of which below a certain
depth is of unknown materials and unknown conductivity,—as is
really the case with the Earth, but that it is a reservoir of heat
which it transmits to a surface layer of rock 8500 feet deep.—having
a conductivity of :006,' and that in 100 million years it has cooled
down so that this surface stratum possesses an increment of 35 of
a degree of heat per foot.

Secondly, let us assume a similarly unknown globe having a
surface layer of rocks also 3500 feet deep, but composed of two
equal layers, the external one having a conductivity of :003, and
the inner layer -009, the average conductivity of the two strata
would be :006, the same as before; but as the increment of heat
varies inversely as the conductivity, with the same flow of heat, the
outer layer would increase in temperature at the rate of 35 of a
degree per foot, and the inner one +; of a degree per foot. Thus
the average rate of increase of temperature with the same loss of
heat taking place would be 3; of a degree per foot.? The conductivity
averaging the same as in the first example, and the increment of heat
being greater, the inferred age of the globe would be less than 100
million years.

But, as we have already assumed, only the same loss of heat taking
place, the actual age of the globe, if its constitution in other
respects were the same, in both cases would appear to be more
correctly estimated at the same figure. Should, however, the calcu-
lation be based upon the rate of increase of the outer layer and the
average conductivity of the two layers, a practical error that might
readily occur in estimating the increment of heat in borings, and
the average conductivity of the materials of the Earth within our
reach, the age of the Harth would be inferred as only 25 million
years.’ It is, however, quite evident that all these conclusions

1T adopt in all cases the British Association Unit of Conductivity, viz. centimetre—
gramme—second.

2 This is arrived at by calculating the total increase of heat downwards in both
cases and dividing by 3500 feet the ‘total thickness of the strata.

3 In these illustrations, and my reasoning throughout, for the sake of simplicity I
omit ail consideration of specific heats, as they do not affect the line of argument
adopted, except that in nature they further complicate the thermal effects.

T. Mellard Reade—The Age of the World. 149

cannot be right, and, further, that any estimate of age from the
thermal condition of the crust may be further vitiated by our
ignorance of the nature, constitution and materials of the globe
underlying the outer strata.

These, I think, are the nature and character of the errors incidental
to any calculation of the actual age of the Earth from the outer
crust of sedimentary rocks. Possessing as they do varying con-
ductivities, and being of various thicknesses, the average con-
ductivity of the whole has not improbably been overestimated, and
the average increase of heat overstated, while the combined resistance
of strata of varying conductivities may be greater to the passage of
heat across them than what would be inferred, even from a correct
average, as was shown to be the case in my second theoretical
example.

If, in addition, we assume that our crust rests upon a basement
of rocks analogous to granite possessing high conductivities, it is
evident the more non-conducting envelope would be retained at a
high increment of temperature for a longer period than if the whole
mass of the Earth underneath possessed only the same conductivity
as the crust. Nor should it be lost sight of in this inquiry, that the
strata we are acquainted with are not cooling down from a state of
fusion, but are deposits laid down upon the surface and gradually
heated from below. This, again, obscures the results, and, indeed, the
question becomes so exceedingly complicated, that it is beyond my
powers to unravel ; but it is not inconceivable that an initial incre-
ment of temperature might be retained in this way for a lengthened
period.

The cumulative results of these possible errors might then at
least quadruple the maximum age of the Earth as inferred from
calculation. At all events, I trust that I have shown the extremely
untrustworthy character of averages in such an investigation. But
these are not by any means all the arguments that can be urged
against the method—the data, as ascertained by experiment, being of
a complicated and contradictory character.

Before dealing with the purely geological aspect of the question,
it will be well shortly to examine the nature and extent of the data
forming the vital elements of the mechanical problem.

Sir W. Thomson states the variation of the increase of temperature
to be from 3+, of a degree Fahr. in some localities, to as much as 75
in another per foot of descent, but =; is accepted as a rough mean.

The Reports on Underground Temperature by the British Asso-
ciation show most remarkable differences in localities not very far
apart. Thus, according to experiments made by Mr. Fairbairn at
Astley Pit, Duckinfield, Cheshire, the average rate of increase was 1°
every 80 feet for a depth of 685 yards; while similar experiments at
Rose Bridge Colliery, Ince, near Wigan, for a depth of 815 yards,
gave an average increase of 1° in every 54:5 feet.' Again, the
rate of increase in some of the wells in Paris is 1° for every 50 to 60
feet; while the great well of La Chappelle at Paris showed, at a depth

1 British Association Report on Underground Temperature, 1870, pp. 31-2.

150 T. Mellard Reade—The Age of the World.

of 600 métres, an average increase of 1° in 94:3 feet.1 In experiments
made at Przibram, in Bohemia, by Herr Johann Grimm,’ Director of
the School of Mines, in a depth of 1900 feet, there was an increase of 1°
in every 141 feet. ‘The experiments at the Mont Cenis Tunnel show
an increase of 1° in 93 feet, without correction for the convexity of
the ground.

If, however, there exist this variation in the average increase of
temperature of each total depth of rock penetrated, there is still more
variation in the rate of increase in different parts of the same bore,
the variation in the Bohemian mine being from 1° in 46 feet to 1° in
1400 feet.

On the other hand, if we refer to the conductivity of certain rocks,
we find, according to the revised scale in the experiments made by
Herschel and Lebour,’ the thermal conductivities vary from -O08&2
for opaque white quartz to -00065 for cannel coal. I understand
Sir W. Thomson’s average was founded upon the conductivity of
only two descriptions of rock, viz. Calton trap rock and Craigleith
sandstone, estimated respectively by him, if reduced to British Asso-
ciation units, at 00266 and -00689.!

Without going further, I think sufficient has been said to show on
what an insecure basis this tremendous superstructure of inference
has been built. From experiments only made in a few places, and
necessarily upon rocks, geologically speaking, subject from time to
time to great fluctuations of temperature, and in mere scratches in
the Harth’s surface, through all manner of variations, the first average
necessary to the calculation has been educed, viz. a ratio of increase
of heat of 1° per 50 feet.

The average conductivity is a still greater assumption, because, in
the first place, the relative amount of each class of rock composing
the crust of the Earth and its conductivity should be calculated,
which is not done, and would prove very difficult to even approxi-
mately estimate. Neither are laboratory experiments on conductivity
conclusive, as a mass of rock through its structure may behave in a
different way to a small piece, while the impossibility of testing in
any way the average conductivity of the materials of the interior of
the Harth, subject to such enormous pressure and heat, is apparent.
It is also not at all improbable that frequent variations of strata,
possessing different conductivities, may create interference in the
transmission of heat; for it is proved that laminations increase the
non-conducting property of rock across the planes of lamination.

If we turn from this most complex and difficult problem, to study
the history of the Harth, and form our views by induction from
observation, we find that from the earliest periods to the present
time the known crust of the Earth has been in continual process of
construction, or reconstruction, by sedimentary and volcanic deposits,

1 [bid. 1873, p. 253. 2 [bid. 1875, p. 1

3 British Association Report on Thermal Gann Aa of certain Rocks, 1875, p. 57.

* The estimate is really made in terms of the thermal capacity of the unit of
bulk, which is averaged at 400; the unit in length being a British foot, and unit of
time a year.

T. Mellard Reade—The Age of the World. 151

the result of atmospheric waste and volcanic emissions and intrusions ;
that this composite body, called the crust, has, from time to time,
throughout all geologic ages, been not only broken up, but heated
matter has been injected into it! or thrown over it; and that this has
occurred at one time or another over the whole of the known globe.

Not only has this been the course of events, but the great mountain
chains—the Andes, the Alps, the Pyrenees, and the Himalayas’—
have been thrown up at a comparatively recent time, geologically
speaking, so that the more we restrict the age of the world, the hotter
should the strata be under those great continents on which these
mountain chains rest.

To get out of this dilemma is impossible; for we cannot consider
these volcanic outbursts as mere local effects, the volcanos at present
active being in lines thousands of miles long, the effect of deep-
seated forces probably connected with central heat, but, even if not,
fed by lakes of molten rock sufficient to set all calculations of secular
cooling at defiance.®

A study of existing volcanos also shows that molten rock at the
surface does not act now in the way Sir W. Thomson assumes
it did in his hypothetical incandescent globe. Why it should not I
cannot conceive. In the volcano of Kilauea, Hawaii, in the Sand-
wich Islands, the molten rock boils up in the crater, while waves of
red-hot matter dash against the surrounding cliffs, and break in in-
candescent spray. If molten rock does this now, why should it in
the first formation of the globe set suddenly solid from the circum-
ference to the centre, as required by Sir W. Thomson’s theory,
and ever afterwards be gradually cooling as an iron shot might cool
from a white heat ?

1 Prof. Judd points out, in his admirable “ Contributions to the Study of Volcanos,”
Grou. Mac. 1876, p. 211, that in the Southern Tyrol, during the Permian period,
“‘enormous masses of volcanic rock were erupted, leading to the formation of volcanic
mountains at least 8,000 feet to 9,000 feet high.” The great “ Whin Sill” has also
been proved by Topley and Lebour to be a vast intrusive sheet. Innumerable similar
examples may be quoted; and as it is usually only by denudation we get a glimpse
of those volcanic rocks occupying the interior of the crust, we may be sure there are
many others unknown because undisclosed.

2 Ramsay, Geological History of some of the Mountain Chains and Groups of
of Europe, Mining Journal, 1875. Judd, Contributions to the Study of Volcanos,
pp- 1338-41.

3 As a proof of the failure at present to establish any law of increase of tempera-
ture, the remarkable temperature results in the boring at Sperenberg, near Berlin,
4172 feet deep, may be quoted. In this case the first 283 feet were in gypsum, with
some anhydrate, and the remainder entirely in rock-salt. Although rock-salt possesses
a considerably higher conducting power than even quartz, being -01144, and more
than twice that of Aberdeen granite, the rate of increase of temperature averaged 1°
per 51:5 feet. (British Association Report on Underground Temperature, 1876,
p- 206.) If the rates of increase should be inversely as their conductivity, on the
supposition of an uniformly cooling globe, the increase of temperature should, com-
pared with Mont Cenis, not be more than 1° per 200 feet. Does it not suggest that
the source of the heat must be nearer the surtace, or that there exists beneath, some
mass of rock abnormally heated ?—a supposition consistent with the geological fact
already stated of the intrusion of heated matter into the crust of the globe and at
yarious epochs of its history.

4 Log Letters of the Challenger.

152 T. Mellard Reade—The Age of the World.

Reasoning from observation, as a geologist is bound to do, the
greater probability is that the surface would become crusted over in
a way that the lava in a volcano becomes crusted over, and that the
surface rock would be of a vesicular character of less specific gravity
than the molten matter. Nasmyth’s theory of the volcanos of the
Moon’ is founded on the supposition that the molten matter expands
in cooling, giving examples in support of his idea, such as the fact
that a lump of cold cast-iron will float in molten iron. Sir W.
Thomson assumes the rock will cool, contract and sink in the molten
mass. Which is right? Nasmyth certainly has had the most
practical experience of molten metals! That a cooling globe solidi-
fies from the surface, I think the Moon is a striking proof.’

The crust would most probably solidify and break up again and
again, and hot materials be injected into, through, and on to the
surface.

A glance at a map of the volcanos of the Moon should satisfy
any one on this point, for there are the evidences of almost countless
myriads of volcanic rings or craters, covering the whole surface and
superimposed or breaking through one another in a most remarkable
way. Observation, then, tells us that a crust will most likely form
on a globe of molten rock. Now, in the case of the Harth, comes
in the question of denudation; for no sooner is a sufficient crust
formed than the aqueous vapours and atmospheric agencies begin to
eat it down, and thus we have a composite crust of sedimentary and
volcanic materials, such as the geologist is acquainted with as exist-
ing in Nature. There is also this fact in favour of a retention of
heat by the globe, that pumice rock, and any rock of a loose or
vesicular nature, possesses small conducting power,—the proportion
of absolute resistance to the passage of heat being as 1818 in dry
pumice to 87 in rock-salt.

The laminations and alternations of beds is also, I strongly believe,
favourable to the retention of heat,? so that we see a coating must be
gradually formed round our incandescent globe like the felt round a
steam boiler.

This speculation, though interesting, is rather outside of true
geological inquiry; it is beginning at the wrong end. No one yet
has ever had a glimpse of this primitive globe; for though we have
a knowledge of a thickness of rock estimated at from 14 to 17
miles, the base is practically the same as the topmost story of the
superstructure. These original crusts have most likely been broken
up, melted and destroyed long since, as sediments have been also
melted and destroyed.

Much more may be said on the subject, but I trust enough has
been shown to prove that the hypothetical way of treating such

1 The Moon as a Planet, as a World, and a Satellite, Nasmyth and Carpenter.

? Mr. Mallet has controverted Nasmyth’s conclusions, Proc. Roy. Soc. 1874,
p- 366. Nevertheless, he admits the fact of certain pieces of cold cast-iron floating
upon molten iron.

3 In my Presidential Address to the Liverpool Geol. Soc. Session 1875-6, ‘On the
Moon and the Earth,” it is suggested, p. 89, that “the sediments accumulating on
the Earth from age to age must act as a non-conducting envelope.”

T. Mellard Reade—The Age of the World. 153

problems, however clever, ingenious and interesting, is unreliable.
Geology demands that a thing should be tested as you go along; for
so little is really known of the physics of the Earth that we continu-
ally find facts in discordance with preconceived notions, though,
when once known, it is easy to see that such and such a thing might
have been predicted by theory.

It is proverbially easy to prophesy after a thing has happened, and
it is just as easy to see that any proved fact is in accordance with the
laws of physics. Nevertheless, the observer is continually discovering
new things that no one predicts. If there is any one thing that
physicists ought to have predicted, it is that the bottom of the ocean
is uniformly occupied by water of a very low temperature. Now I
think there are few physicists who would not have supposed that the
secular cooling of the Earth would, to some degree, have influenced
the bottom water of the ocean that must have travelled thousands of
miles in contact with it, yet the Challenger temperature soundings
prove that it has no appreciable effect."

It is impossible in this space to explain the way the geologist
approximates to the immense age of the Earth, and as I have already
elsewhere? attempted the calculation on a geological basis, it is thus
less necessary for me to do so now. A calm investigation of all the
multitudinous facts which necessarily enter into the problem satisfies
me, at all events, that no case has been made out for restricting the
age of the Harth below that demanded by Geology, even on the
assumption of a globe of molten materials to commence with.
According to Sir W: Thomson’s expressed opinion, “The general
climate cannot be sensibly affected by conducted heat at any time
more than 10,000 years after the commencement of superficial
solidification.” So that as the rate of deposition of sedimentary
rocks cannot by this hypothesis have been affected by the interior
heat of the Earth, it tends to show it is a reasonable assumption on
the part of the geologist that the rate of formation of these rocks,
dependent on atmospheric degradation, was in former ages very
much what it is at present.’

I am also of opinion that the rate of increase of underground
temperature has, probably, been for long ages past very much what
it is now; for if I have shown that the interior heat of the Earth is
introduced into the crust by intrusion, as well as by conduction, there
is even now, according to Sir W. Thomson’s showing, a vast reservoir
of unexhausted heat; nor must we forget that the present crust of
the Earth is not an originally formed product, but one built upon

1 Mr. Croll (Climate and Time) attempts to explain why the secular cooling of
the Earth does not affect the bottom water of the Ocean, but the explanation comes
after the knowledge of the fact.

2 “On Geological Time,’ Presidential Address, Liverpool Geol. Soc. Session
1876-7.

3 Sir W. Thomson, however, infers, that as the Sun must have been hotter in former
ages, the atmospheric agencies were then more potent; but this is all pure hypothesis,
no proofs that they were being adduced. Mr. Croll again has his own hypothesis on
the subject, but the fact is we know absolutely nothing of the Sun’s heat, and cannot
safely reason on conjectures.

154 C. Lloyd Morgan—Geological Time.

the ‘pre-existing materials: so that if we assume a freer circulation of
underground heat below this crust than through it, as I think volcanic
action indicates, and a successive building up of crust upon crust as
it is destroyed from below, together with an intrusion of melted
materials which from time to time, as we know, has taken, and is
taking place, the conditions of varying increments of heat actually
met with in equal spaces downwards will be pretty well fulfilled.
That this circulation of heat takes place at great depths is rendered
probable by the alteration of the positions of volcanos from time to
time in the Harth’s history, by the tremendous evidences of volcanic
effects in Tertiary times, and by existing volcanos.’

Facts are safer than theories, and as at 100 miles deep, even
according to Sir W. Thomson’s theory, the rocks now must be at
7000° Fahr., if this circulation of internal heat takes place as I suggest,
there is sufficient store of heat in the Harth now to carry us on com-
fortably for another 1000 million of years, without those reconstructive
agencies on which our existence depends becoming impotent.

II].—Grotocicat Time.

By C. Luoyp Morean, F.G.S., A.R.S.M.
(Part I.)

NE of the most important questions which modern geologists

have to answer is that which refers to the duration of Geolo-
gical time. How long is it since the Glacial epoch? What was
the date of man’s appearance on the earth ? How many ages have
rolled by since the earth first became the habitation of organized
beings? Such are the questions, daily repeated, to which we must
make some answer, or, if need be, honestly confess our ignorance.

It is interesting to notice the change which has taken place,
within the last century or so, in the opinions of educated men on
these fundamental questions. At the beginning of the present
century it was the almost universal belief, that the earth had been
in existence some 5800 years, and the human race some six days
less. Now there are few men of ordinary education who do not
admit the great antiquity of man, and the vast age of the globe
which he inhabits; while theologians vainly endeavour to persuade
us that the Mosaic six days meant six long geological periods,
forgetful that Moses (if indeed he was the author of Genesis) was
writing a history of the Jewish race and their beliefs, so far as he
could gather it from tradition, not a treatise on Geological Cos-
mogony.

But just as a young man who has been subject to too great and
unwise restraint, when he has once broken the fetters, rushes into

1 A study of Mr. Darwin’s ‘“‘ Geological Observations,’’ published first as early as
1844, will, I think, convince the most sceptical of the continued activity of the
volcanic forces in South America on a tremendous scale, which must leave some im-
pression on underground temperature there in future ages, though I agree with Prof.
Judd that there has not necessarily been the same actual display of energy at every

period of the Earth’s history. This is dependent on many causes, which I hope to
be able to further explain at a future time.

C. Lloyd Morgan—Geological Time. 155

too great and equally unwise excess, before he settles down into the
steady earnestness of sober manhood, so did geologists, when they —
had freed themselves from the restraint imposed upon them by a
belief in the truth of the Mosaic account of Creation, make too
great drafts on the bank of Geological Time. “In the economy of
the world,” said Hutton, “I can find no traces of a beginning, no
prospect of an end.” Geological Time was considered illimitable,
and a false analogy was set up between the boundless infinity of
space and the vast immensity of past time. Geologists began to
speak of millions of years as mere moments in the antiquity of the
earth’s history. Thousands of millions, billions, and “vast ceons”
of past time were spoken of with impunity. This error, for we
shall shortly see that it was an error, arose partly no doubt from our
utter inability to conceive periods of time which greatly exceed in
length the three or four thousand years with which the history of
nations has to deal. Directly we cease to have a clear mental image
of the length of time spoken of, and can no longer refer it to any
standard, we get into the region of mere empty words which mean
nothing. ‘A million of years”—it is easily said, but really conveys
very little to the mind. Mr. Croll, feeling the truth of this, helps
us to conceive this immense period of time. “There is one way,”
he says, ‘of conveying to the mind some idea of what a million of
years really is. Take a narrow strip of paper, an inch broad, or more,
and eighty-three feet four inches in length, and stretch it along the
wall of a large hall, or round the walls of an apartment somewhat
over twenty feet square. Recall to memory the days of your boy-
hood, so as to get an adequate conception of what a period of a
hundred years is. Then mark off from one of the ends of the strip
one-tenth of an inch. The one-tenth of a inch will then represent
one hundred years, and the entire length of the strip a million of
years. It is well worth making the experiment,” Mr. Croll adds,
“just in order to feel the striking impression that it produces on the
mind.”

Having grasped in some degree the vast period of time conveyed
by that little phrase “a million of years,” the geologist is in a better
position to hear patiently the arguments brought forward by physi-
cists for the definite limitation of that time, which the School of
Uniformity had taught him to consider as indefinite in length. Of
those who have made this subject their special study, Sir William
Thomson takes the lead, and he has considered the matter from
more than one point of view.

I will here extract a short description of his results from Professor
P. Guthrie Tait’s “Recent Advances in Physical Science,” in which
there is a brief réswmé which “contains nearly all that is accurately
and definitely acquired to science upon the subject.” In the first
place, then, Sir William Thomson takes into careful consideration
the facts connected with the internal temperature of the earth. It
is a matter of every-day experience that there is a gradual increase
of temperature as we descend into the earth’s crust. But ‘ when-
ever a body is hotter at one part than at another, the tendency of

156 C. Lloyd Morgan—Geological Time.

heat is always to flow from the hotter part of the body to the colder.
Therefore, as the earth’s crust is warmer and warmer as we go
farther and farther down, there must be a steady flow of heat
onwards from the interior to the surface. The earth is therefore
even now losing heat at a certain perfectly measurable and cal-
culable rate.’ This rate has been calculated by Sir William
Thomson. Taking the rise of temperature, over the whole earth’s
surface, “at an average of about one degree for one hundred feet of
descent,’ he concludes “that about ten millions of years ago the
surface of the earth had just consolidated, or was just about to con-
solidate.” ‘Thus we can say at once to geologists,” says Professor
Tait, ‘that granting this premiss,—that physical laws have remained
as they are now, and that we know of all the physical laws which
have been operating since that time,—we cannot give more scope for
their speculations than about ten or (say at most) fifteen millions of
years.

It is hardly necessary to point out how uncertain are the data on
which these calculations are based, and with uncertain data the most
rigorous and accurate mathematics can do little. As Professor
Huxley has remarked, if we throw peascods into our mathematical
mill, we cannot expect to extract wheaten flour. In the first place,
the laws of the conduction of heat through intensely heated bodies,
which are not homogeneous, are by no means well understood, and
the earth’s crust is, probably, not only heterogeneous in composition,
but partially solid and partially liquid. In the second place, the
rate of increase of temperature taken 1° for every one hundred
feet descent into the earth, though, perhaps, a fair average of known
observations, is but a rough generalization. Could we know what
is the rate of increase of temperature for every one hundred feet of
descent over the vast oceanic areas of our globe, we might have to
modify our generalization in a very important degree. I am not
aware whether Sir William has, in his estimate, taken into con-
sideration the amount of heat—in all probability great—which has
been generated in the earth by contraction of her sphere and the
consequent lateral pressure, or the amount which, as suggested by
Professor Huxley, may have been produced by chemical combination.

Geologists may, therefore, well hesitate before they accept this
limitation to ten or fifteen millions of years. Sir William Thomson
himself, however, takes—or until a recent date took—a liberal view
of the matter, and granted to geologists about one hundred millions
of years.

Sir William Thomson’s second argument depends upon tidal
retardation. The fact that the tide waves act as a check upon the
rotation of the earth on her axis, is now well known. The earth,
in fact, revolves within a friction-brake which has caused a slacken-
ing of her rate of rotation, even within historical times; for partly
from this cause the moon “seems to have been moving quicker as
time has gone on since the eclipses of the fifth and eighth centuries
before our era.’’ Now this action, if continued long enough, will
at length cause the tide waves to remain fixed in their position on

C. Lloyd Morgan—Geological Time. 157

the earth’s surface, and will cause “ the earth constantly to turn the
same portion of its surface towards the moon, and therefore to rotate
about its axis in the same period as that in which the moon revolves
about it. This most remarkable ultimate effect we see already pro-
duced in the moon—it is precisely the same thing—we see the
moon turning almost exactly the same portion of its surface to the
earth at all times.”

“Tt being thus established that the rate of rotation of the earth
is constantly becoming slower, the question comes: How long ago
must it have solidified in order that it might have the particular
amount of polar flattening which it shows at present?” To which
Professor Tait gives the somewhat indefinite answer: ‘“‘That because
the ‘earth is so little flattened it must have been rotating at very
nearly the same rate as it is now rotating when it became solid.
Therefore, as its rate of rotation is undoubtedly becoming slower and
slower, it cannot have been many millions of years back when it
became solid, else it would have solidified into something very much
flatter than we find it. That argument, taken along with the first
one, probably reduces the possible period which can be allowed to
geologists to something less than ten millions of years.”

Now, even if we grant, as is quite probable, that, when it first
solidified, the earth was a more oblate spheroid than at present,
it is by no means probable that she would have continued to possess
the self-same figure until now! Sir William Thomson himself and
Mr. George Darwin, in their papers on the possible changes of
the earth’s axis of rotation, express a belief that the earth would
readjust itself to its form of equilibrium, if by some chance it should
at any time fail to conform to that figure. This might be effected
either “impulsively by means of earthquakes,” or gradually, in
which latter case there might have been a special tendency for the
melted products of volcanic action to be extruded in the neigh-
bourhood of the polar regions; and it is a noteworthy fact that
polar lands are remarkably volcanic in their character. No geolo-
gist who has studied the contortions of strata in any mountain
region could believe that, since its first solidification, the earth’s
figure had been absolutely unaltered, while many would contend,
and with much weight, that whatever its original form, during the
mechanical deposition of strata its present figure must have been
produced. ‘“ We cannot infer from the present shape of our globe,”
writes Mr. Croll, “what was its form, or the rate at which it was
rotating at the time when its crust became solidified. Although it
had been as oblate as the planet Jupiter, denudation must in time
have given it its present form.” Polar ice-caps and the varying
distribution of land and ocean introduce uncertainties into the
data for calculation, which must prevent our placing any implicit
faith in the results obtained.

The third point taken into consideration by Sir William Thomson,
in his estimate of the length of geological time, is the probable
duration of the sun’s heat. There are several theories of the
origin and source of solar heat. Among others, as indeed we might

158 C. Lloyd Morgan—Geological Time.

expect, is one which accounts for this heat by combustion, such
as is carried on when we burn coal in a fire-grate. But “to main-
tain the present rate of radiation,”’ says Mr. Croll, ‘it would require
the combustion of about 1500 pounds of coal per hour on every
square foot of the sun’s surface, and were the sun composed of that
material, it would be all consumed in less than five thousand years.”
“The opinion,” he adds, “that the sun’s heat is maintained by com-
bustion, cannot be entertained for a single moment.”

Another hypothesis shall be stated and answered in the words of
Professor Tyndall (Heat a Mode of Motion, p. 478): “The sun
we know rotates upon his axis once in about twenty-five days; and
the notion has been entertained that the friction of the periphery
of this wheel against something in surrounding space produces
the light and heat. But what forms the brake, and by what
agency is it held, while it rubs against the sun? Granting, more-
over, the existence of the brake, we can calculate the total amount
of heat which the sun could generate by such friction. We know
his mass; we know his time of rotation; we know the mechanical
equivalent of heat; and from these data we can deduce, with
certainty, that the force of rotation, if entirely converted into heat,
would cover less than two centuries of emission.” The Gravitation
Theory is, indeed, the only hypothesis which is generally admitted
by physicists, but of that theory there are two forms. One of
these, which is known as the Meteoric Theory, was first proposed
by Dr. Meyer, of Heilbronn. According to this hypothesis, the
sun’s heat is maintained by the continual fall upon his surface
of meteoric matter, by a constant rain of meteorites. The amount
of energy exerted by one pound weight falling upon the sun from
an infinite distance would be sufficient to raise, says Mr. Croll,
one thousand tons to a height of five and a half miles. “It would
project the Warrior, fully equipped with guns, stores, and ammuni-
tion, over the top of Ben Nevis.” ‘“Prodigious as is the energy
of a single pound of matter falling into the sun, nevertheless a
range of mountains, consisting of a hundred and seventy-six cubic
miles of solid rock, falling into the sun, would maintain his heat
for only a single second. A mass equal to that of the earth would
maintain the heat for only ninety-three years, and a mass equal
to that of the sun itself falling into the sun, would afford but
thirty-three million years’ sun heat.” The Meteoric Theory has now
given way before that known as the Contraction or Condensation
Theory of Helmholtz.

If we take a closed cylinder, in which works a closely- Being piston,
and, by a sudden downward motion of the piston, condense the air
within the cylinder, we shall raise the temperature of that air, and
this to such an extent, that a piece of German tinder, placed at the
bottom of the cylinder, may be ignited in this way. If the pressure
were to be brought to bear slowly instead of rapidly, an equal
amount of heat would be produced, and if, instead of the external
force of muscular energy, the internal force of the gravitation of the
particles of the gaseous air towards each other were to cause the

C. Lloyd Morgan—Geological Time. 159

condensation, the same effect would be produced: heat would be
evolved. According to the Nebular hypothesis, the primitive fire-
mist, or nebulous mass, out of which our system has been elaborated,
once extended beyond the orbit of the sun’s most distant planet.
During the condensation from that nebulous state to the present
condition of the sun, a definite amount of heat must have been
given out by that luminary. This amount has been approximately
calculated. It would suffice for the radiation of some twenty millions
of years, or if, as is probable, the sun’s density increases towards
its centre, for that of a somewhat longer period. If gravitation,
therefore, be the only possible source of sun heat, all geological
phenomena will have to be comprised within a period of less than
twenty millions of years. But it is highly improbable, as Mr. Croll
has pointed out, that the nebulous mass should have existed in the
gaseous state, without possessing a high temperature to begin with.
Nay, rather, it is most probable that it was to its excessive tempera-
ture that its intensely rarefied condition was due. How, then, was
this high initial temperature produced? The answer must be a
purely hypothetical one. But there is one way in which this
temperature may have been produced.

Our system is believed by astronomers to be moving onward
through space, probably in the direction of the constellation Her-
cules, and from analogy we may well presume that other suns are
likewise in motion. Sirius, for example, has a relative motion to
that of our sun, which tends to increase the distance between these
bodies by about twenty miles in every second of time. Other
celestial globes must be approaching each other. Taking an hypo-
thetical case, Mr. Croll tells us that, ‘“‘ Two bodies, each one half the
mass of the sun, moving directly towards each other with a velocity
of four hundred and seventy-six miles per second, would by their
concussion generate in a single moment fifty million years’ heat.”
“Why may not the sun have been composed of two such bodies?”
he adds, “ And why may not the original store of heat possessed by
him bave all been derived from the concussion of these two bodies?”
«Two such bodies coming into collision with that velocity would be
dissipated into vapour by such an inconceivable amount of heat as
would thus be generated ; and when they condensed on cooling, they
would form one spherical mass like the sun.”

Thus, although the consideration of the sun as our source of heat
would seem at first to limit the history of the earth, as the habita-
tion of life, to some fifteen or twenty millions of years, a method by
which the sun-heat may have sufficed for a hundred million of years
is at any rate not inconceivable.

On the other hand, Mr. Norman Lockyer “thinks it likely that
many of the substances which we believe to be elements, because we
have not been able to decompose them, are really compounds; and
that, during the early periods of a star’s lifetime, their components
existed in an uncombined state, the dissociation being perhaps due
to intense heat; when the heat was so far reduced that it was no
longer able to keep the elements apart, chemical combination took

160 C. Lloyd Morgan—Geological Time.

place, and the process may have set free a very considerable quan-
tity of heat; in other words, when the energy which had before
been occupied in preventing combination became no longer equal
to the task, it appeared as sensible heat.” That the data, on which
these speculations concerning solar radiation are conducted, are not
of a perfectly certain nature, may be gathered from the following
quotation from Professor Tait’s sixth lecture: “The very lowest
estimate which we can make of the capacity of the sun for heat is
such that, cooling at the present rate—losing energy at its present
rate—the sun cannot possibly cool more than a single degree Centi-
grade in seven years. It may be, on the highest estimate we can
take, one degree in seven thousand years; the data are very un-
certain; but we may say that these are the limits between which it
must lie.”

Physically speaking, therefore, we may consider that geological
time must be comprised within limits of from ten to one hundred
millions of years.

Let us now turn to the other side of the question, and consider
past time from the geological standpoint. The questions for con-
sideration are obviously these. In the first place, what is the
average thickness of the sedimentary formations of some definite
area, say Great Britain? in the second place, at what rates were they
severally and collectively deposited ? and lastly, what was the length
of time occupied in their deposition ?

It is essentially necessary that we should confine our attention to
the thickness of the rocks of a definite area. We know next to
nothing of the geology of the world taken as a whole. Living as
we do on the land, we have only the power of studying at most
somewhat less than one-fourth of the earth’s surface, and of that one-
fourth but a very small portion is actually known to us. Mr. Croll
has calculated that, assuming the duration of geological time to be
one hundred million years, at the present rate of denudation the
total mean thickness of rock formed during that time cannot exceed
five thousand feet. This may be so, and Mr. Croll’s supposition,
that in the depths of the Atlantic, Pacific and Indian Oceans, “ little
or no stratified deposits may exist,” may possibly be true. Our
wisest course, however, in the existing state of knowledge, is, as it
seems to me, to study our own group of rocks, the conditions under
which those rocks were formed, and the evidence which we have, or
have not, for long breaks in the continuity of their deposition. This
is the task to which I will now apply myself.

Professor Ramsay, Director-General of the Geological Survey of
Great Britain, tells us that the sedimentary formations of that area
have a maximum thickness of upwards of seventy-two thousand feet,
(thirteen and a half miles). But to this must be added, say some
geologists, “the quantity of rock removed during past ages by
denudation.” ‘In many places,” writes Mr. Croll, “the missing
beds must have been of enormous thickness. The time represented
by beds which have disappeared is, doubtless, as already remarked,
much greater than that represented by the beds which now remain.”

C. Lloyd Morgan—Geological Time. 161

We must be careful, however, not to confuse the maximum thickness
given by Professor Ramsay with the average thickness of the strata.
In different parts of England the same series of strata will often
vary much in thickness. For example, a band of Oolitic rocks runs
across England from the coast of Yorkshire to that of Dorsetshire.
Near Cheltenham the thickness is more than 500 feet, while in
Dorsetshire it is found to be reduced to less than 25 feet! Other
instances might be given to any extent. The Kimmeridge Clay
near Oxford is some 90 or 100 feet thick; but in the Sub-wealden
boring near Hastings it was found to have a thickness of some 700
feet. We may therefore fairly consider that the maximum estimate,
seventy-two thousand feet, is considerably in excess of the average
thickness of the sedimentary rocks of Great Britain. The argument,
too, as to the amount of rock swept away in past times by denuda-
tion, must not be pushed too far. In many parts, indeed, whole
groups of strata have ‘disappeared from the rocky structure of our
isiand from this cause; but in other parts these groups are well
represented. From the fact also that during the elevation of our
islands the strata must have been tilted so as to assume an inclined
position, denudation has exerted its destructive influence on the
edges of the strata, and therefore has not precluded us from estimat-
ing their original thickness. It is as if a fire had occurred in our
geological library, which did indeed destroy a great mass of
literature, but acting upon the exposed edges of the books, left a
portion of each in its place, which portion represents the thickness,
but not the size of the book.

But there is another fact to be taken into consideration. Professor
J. Young (Pres. Address, Sect. C, Brit. Assoc., 1876) has pointed out
that our method of arranging the rocks in one long series, from
Laurentian to historical times, is erroneous, and leads us to give an
excessive estimate of the thickness of our strata. He argues that
some groups, which we are wont to arrange in a continuous vertical
series, were in reality contemporaneous, and should be arranged side
by side in parallel series. Our strata do not furnish us, as is
generally taught, with one continuous though mutilated volume, but
with two or three contemporaneous and also mutilated volumes,
bound up together. Let us consider for a moment the strata now in
process of formation in the neighbourhood of our islands. In the
English Channel sand is being deposited; further west, in the deeper
stiller water south of Ireland, fine mud is being laid down; and
somewhat further west, in the deeper Atlantic, Globigerina ooze is
being formed. Now it can hardly fail to happen that in many
places near the boundaries of these deposits fine mud will be laid
down on the top of Globigerina ooze, on the one hand, and sand on
the fine mud, on the other hand. But how erroneous would be the
conclusions of the future geologist, who, arguing from the fact that
he found in one area the clay lying upon chalk, and in another sand
upon the clay, placed these strata in one continuous series, and took
the maaimum thickness of each. In this way he might easily form
an estimate at least double the true thickness of the formations.

DECADE II.—VOL. Y.—NO. IV. 11

162 Prof. J. Young—Deposits preserved under “ Till.”

And yet in the tables of strata geologists almost invariably adopt
the linear arrangement of strata, and have a tendency to take the
maximum thickness of each group of rocks. Thus we group certain
rocks as under :

Chalk

Upper Greensand

Gault

Lower Greensand

Wealden

Purbeck.
Professor Young, however, in his Address, thought it highly probable
that “the Lower Greensand is contemporaneous with part of the
Chalk, so were parts of the Wealden; nay, even of the Purbeck a
portion must have been forming while the Cretaceous sea was
gradually deepening southward and westward.” Our earth’s history,
indeed, is not like the simple history of one kingdom, but more
closely resembles the contemporaneous history of several provinces.

(Zo be concluded in our next Number.)

Il].—Wuat must BE EXPLAINED BEFORE THE PRESERVATION OF
Deposits unDER TILL 1s EXPLAINED.

By Professor Joun Youne, M.D., Glasgow University.

S Iam one of those who find difficulty in understanding the
preservation of stratified deposits beneath the Till, I would

like to point out to Mr. J. Geikie that he has not correctly stated
the difficulty in his paper (Grou. Mac. Feb. 1878) on “The Pre-
servation of Deposits under Till or Boulder-clay.” The difficulty
really lies in the explanation of how the Till itself was deposited :
were that clear, the preservation of beds beneath it might be at once
intelligible. Admitting the passage of an ice-sheet across the country,
admitting further that the Till is the moraine profonde of such an
ice-sheet, the accumulation of 100 feet of Till beneath the ice-sheet
is a phenomenon which has not been explained, and cannot be passed
over as unimportant. A moving mass of ice, 2000 feet thick,
seems a formidable agent of erosion; yet where I now write nearly
100 feet of Till intervene between the surface and the Carboniferous
rocks, which, where exposed, shows striations having the usual
compass bearing for this neighbourhood. The greater portion of the
Till hereabouts is derived from the Carboniferous rocks of the dis-
trict, but numerous boulders of granite, felstone, schist, and of Old
Red Sandstone sedimentary and volcanic rocks, show that the ice
had brought materials from a wider area. The limits of the
Carboniferous series are about twelve miles to the west and north-
west of Glasgow, that being the direction whence the ice came.
As the ice of a modern glacier pushes the results of erosion before
it, we may conclude that the old ice-sheet with a pressure of about
1000 lbs. to the square inch did the same; indeed, Mr. Geikie has
already accepted this “idea as to how an ice-sheet would behave,”
but without explaining how the alternate exposure and con-

Prof. J. Young—Deposits preserved under “ Till.” 163

cealment was effected in the presence of very thick Till. It
may he said that the ice pushed its moraine profonde before it, but
then Hugh Miller’s “pavements” have always been referred to as
proofs that the ice overrode not displaced the Till already accumu-
lated. And this was inferred from the fact that glaciers, when they
do override their terminal moraines, grind down their new beds.
Professor Geikie has suggested that the upper part of the Till of
Scotland may belong to the same series as the inland Till, may
indeed have been the product of the same ice-sheet, in which case
‘they will indicate for us those portions of the great griind mordne
which, instead of accumulating on or close to the land, were actually
pushed by the advancing ice far out to sea, where they were more or
less affected by marine currents, and sometimes received and pre-
served marine organisms.” Hven this passage does not give a clear
view of how the Till accumulated on the land to such depths as I
have mentioned ; for it must be remembered that Till contains from
50 to 65 per cent. of impalpable mud which, had the moraine profonde
been accumulated on land, would have been washed away by the
waters constantly present beneath moving ice. But the admission
that the upper part of the Till might have been laid down in the
sea without being wholly rearranged is important. The preparation
of a text-book compelled me, four years ago, to record the difficulties
which the ice-sheet did not solve, and which I had always pointed
out in my lectures. I then suggested as a possibility that the Till,
pushed by the advancing ice-sheet off the land, might have gathered
on the sea-floor in comparatively undisturbed water, protected by
ice, either the land-ice or a mass of ice of greater size and duration
than the modern ice-foot. This compromise between land-ice and
sea-ice seemed the only possible way of reconciling the thickness
of the Till at places with its generally local aspect. Deposits of
promiscuous rubbish over stratified material without disturbance of
the latter is thus possible, while the crumpling and contortion of
the strata in certain places might be the work of bergs or coast-ice,
the erosion perhaps due to the subglacier waters. When we are
asked to believe that the Till is not merely a product of land-ice,
but accumulated on land under a moving ice-sheet, and are further
asked to accept the erosion, the contortion and the non-disturbance
of stratified beds as alike the accompaniments of the passage, not of
land-ice, but of the morainic matter pushed forward by it, we are
practically asked to give up the attempt to solve a difficulty which
has never been really faced. This was, I assume, not Mr. Geikie’s
meaning ; indeed a foot-note betrays consciousness of the unsatis-
factory character of the argument, though the suggestion that the
interglacial beds were not eroded by the ice because they were
frozen scarcely adds to our knowledge. Mr. Geikie says that the
varying, I should call it eccentric behaviour of the ice, is no more a
difficulty than the erosion by a river at one point, the deposit of
alluvium at another. But this, like all analogies, is a dangerous
illustration : the alluvium is thrown out by the river and left. It
would indeed be a support if the river laid down thick alluvium

164 Dr. Henry Woodward—On Peneus Sharpii.

and did not erode it: if further the alluvium was derived from the
district in which it was laid down. As the major part of what has
been written on the “ Glacial Epoch” rests on preconceptions and
@ priori anticipations as to what ice would do, I shall not discuss
the evidence on which even authoritative statements have been put
forth. My wish is to learn how the 100 feet of Till were accumu-
lated : for even if they were piled up under a thinning glacier, it
still remains to be explained how so vast a quantity of detritus
could have been won from a small area by an agent steadily di-
minishing in force.

IV.—Note on Penvzxus Saarri, 4 Macrurous Drcarop Crusta-
CEAN, FRom THE Upper Lias, KinestHorpPr, NEAR NORTHAMPTON.

By Henry Woopwarp, LL.D., F.R.S., ete.

(PLATE IV.)

N a paper on the Lias of Ilminster, by my friend Mr. Charles
Moore, F.G.S., communicated to the Somerset Natural History
Society, and published in their Proceedings (1865-6, vol. xiii. p. 72),
I gave a list of the Crustacea submitted to me for examination by
Mr. Moore, among which was a species belonging to the genus
Peneus, referred by me to P. latipes, Oppel, from the Upper and
Middle Lias of Ilminster.

In my fourth Report “On the Structure and Classification of the
Fossil Crustacea,” presented to the British Association (Section C.
Geology), at the Norwich Meeting, August, 1868, I noticed the
occurrence of a second British species belonging to this genus from
the Lias of Northamptonshire, and named by me Peneus Sharpit.

The following is an extract from my Report, p. 74:—“I have
now to notice another species of the genus Penceus of Fabricius from
the (Loyer’) Lias of Northampton. This is a remarkably per-
sistent “form, and the genus is actually found now living in the
Mediterranean if Dr. Oppel’s determination be correct, which I feel
little doubt in endorsing.”

“This handsome Crustacean” (see Plate IV.) “was not less than
94 inches in length when measured along the dorsal line, the
carapace being about 3 inches, and the abdomen 64; the rostrum
was very strongly serrated, as in the Palemonide, but the serrations
have been abraded in the fossil.

“This form most nearly resembles in size and appearance the
Peneus speciosus of Miinster, but differs slightly in the form of the
border of the abdominal segments, and also in the direction of the
strong and deeply-forked sulcus which marks each side of the latero-
anterior portion of the carapace near the base of the great antenne.
The surface of the carapace and segments was highly enamelled,
some portions of which may still be observed in the fossil.

1 This should be Upper Lias.

2 Dr. Oppel has described five species belonging to the genus Peneus. One

(P. Liasicus) from the Lower Lias of Schambelen and four from the Lithographic
Stone of Bavaria.

Geol. Mas. 1878. NE Smilies Decade II. Vol.V. PL IV.

Mire spy,
eaeteaeet
She

a8

a
Rees

tes.

PENAUS SHARPII, Woodward.
(UPPER LIAS, Kingsthorpe, Northampton.)

Notices of Memoirs—UM. Hébert & Munier-Chalmas. 165

“T have named it Penceus Sharpii, after Mr. Samuel Sharp, F.S.A.,
F.G.S8., who is the discoverer of the fossil.”

My present object in again calling attention to this specimen is to
correct an error made in 1868, when I described it as from “the
Lower Lias”—the fact being, as pointed out by my friend Mr. Sharp,
that it occurs in the very top zone of the Upper Lias at Kingsthorpe,
in a bed in which Ammonites serpentinus, A. communis, and A. bifrons,
are abundant.

This important correction also enables me to avail myself of the
two carefully drawn views of Peneus Sharpii by my friend Miss
Edith Jeyes, to whom I desire to express my best thanks.

The specimen, together with a fine series of Northamptonshire
and Lincolnshire Fossils, from Mr. 8. Sharp’s Museum, now form a
part of the National Collection.

INT OQMrIge AES | (Usp | AMess Iw C ers ys.

—_—<@——_.

“RECHERCHES SUR LES TERRAINS TERTIAIRES DE L’ HUROPE MERIDIO-
NALE.” Par MM. Hésert et Munrer-Cuaumas. (Comptes
Rendus des Séances de Académie des Sciences. tom. 1xxxv.)

DIFFERENCE of opinion between M. Bayan and M. Hébert
with respect to the relative position of the lower Hocene beds

of Rouen and San-Giovanni Jlarione, led the latter observer to
undertake a personal survey of the district of Vicenza. Accordingly,
in company with M. Munier-Chalmas, who carried on the palzonto-
logical portion of work, he not only paid a visit to that locality, but
extended his observations to the Tertiary beds of Hungary. The -
results of these researches are embodied in the paper, or rather series
of papers, now before us. The authors first visited Hungary, and
there, aided by Herr Max von Hantken, the Director of the Hun-
garian Geological Institute, they made a careful examination of the
Tertiary strata. These they describe with some minuteness, and
come to the conclusion that the Nummulitic deposits all belong to
the Middle and Upper Eocene, are divisible into five well-marked
zones, of which four are characterized by different species of Num-
mulites; whilst the Lower Miocene is represented by two beds,
respectively characterized, as in the Paris Basin, by Cyrena convexa
and Pectunculus obovatus.

Proceeding to Vicenza, a parallel series of deposits was made out,
which are described with the same exactitude as the others. The
voleanic rocks of this district, held by many to be contemporaneous,
are considered by the authors to belong to a later period; and the
intercalation, so often cited, of basalts with the beds of limestone, they
maintain is merely apparent. No notice, therefore, is taken of them.

M. Hébert’s opinions concerning the synchronism of these two
series of deposits with each other, and those of the Paris Basin, to-
gether with the various zones into which they are divided, will be
best seen by referring to the table appended to the paper, which is
here reproduced for the convenience of our readers. (See p. 166.)

B. B. W.

of Memoirs—UM. Hébert & Munier-Chaimas.

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Reviews —Prof. Hull’s Physical Geology of Ireland. 167

RAVIEwWS.

Tur PuystcaL GroLogy aND GrEoGRAPHY OF IRELAND. By E.
Hout, M.A., F.R.S., Director of the Geological Survey, Ireland,
and Professor of Geology in the Royal College of Science,
Dublin. Post 8vo. with 2 coloured maps and 26 wood en-
gravings, pp. xvi. and 291. (London: Stanford, 1878.)

Second Notice.
(Continued from the March Number, p. 127.)

AVING thus given his readers an acquaintance with the funda-

mental structure, or, as it were, the internal anatomy of the
country, the author proceeds to discuss the causes of its present
features, its mountains and valleys, its rivers and lakes. And first
taking up the mountains, he naturally, as a geologist, devotes
attention principally to the question of the age of the mountain
ranges, that is, the date (geological) of their first birth, not merely
of their subsequent development or reproduction. It will be quite
unnecessary to explain here any of the steps in this reasoning, but
we shall give a summary of the conclusions which he arrives at.
The entire surface of Ireland, viewed as a whole, consists physically
of a great central plain bounded in most directions, but not entirely
surrounded, by groups of mountains. These naturally group them-
selves into (1) the N.W. Highlands; Donegal and Derry—(2) the
Western Highlands; Galway, Mayo, etc.—(8) the S.W. High-
lands; Kerry, Cork, with outlying ridges—(4) the 8.E. Highlands ; _
Wicklow, Dublin—and (5) the N.E. Highlands; Carlingford, Down,
etc. Of these the last mentioned are decidedly the most recent in
time of birth, they being decidedly later than the Carboniferous era ;
but older than Tertiary. The author believes them to be probably
Permian. They are old volcanic in origin. Then the §.W. High-
lands owe their existence to powerful terrestrial mechanical forces,
which have compressed the bedded rocks into enormous folds and
curves with a general H. and W. axial direction, their great anti-
clinals often broken and partly denuded at the top of curve, and
giving rise to some of the most elevated ground in Ireland, while
the synclinals have been eroded into river-valleys and deep fiords,
so well marked in the indentations of the §.W. coast (Bantry,
Dunmanus, Kenmare Bays). And these forces were brought into
action during the period between the Carboniferous and the Permian.
The other three groups, the western, the north-western, and the
south-western highlands, were of a date between the Lower and the
Upper Silurian (probably ‘pre-Llandovery’), and are due to the
exertion of intense and widespread metamorphic action. The direc-
tion of the axes of these groups is nearly the same, and is between
E.N.E. and N.E.

The ‘great central plain’ next comes under review. This may
be roughly considered conterminous with the Carboniferous Lime-
stone, although this limestone itself is only occasionally visible, the
greater portion of the surface being covered by beds of Boulder-clay

168 Reviews—Prof. Hull’s Physical Geology of Ireland.

and limestone gravel, or-by shallow lakes and sluggish rivers. Ex-
tensive peat mosses or bogs cover large areas of this central plain.’
In places over this great plain we find still remaining detached hills of Coal-
measure rocks, monuments of the former extension of these over the entire area.
The probability of the much greater former extent of the Carboniferous rocks is
well shown, and a little sketch-map given, which indicates that only detached parts
of Donegal, of Galway, and Wicklow were left uncovered originally by one or other
of the deposits of that great period. Such being then the original condition of this
area, the effects of marme denudation on such a surface are discussed, the existence
of such planes, of date even prior to the Carboniferous epoch, poimted out (Sheve
Partry), and the grand instances of the general smoothened or planed down surface
out of which the bold features of the S.W. of Ireland have since been carved by
subaerial action. He then details the features which would result from these suc-
cessive operations, and concludes, that at the close of this long period of disturbance
and denudation, lying between the Carboniferous epoch on the one hand and the
Permian on the other, the surface of Ireland would present the appearance of a plain
partly formed of Coal-measures, and partly of older rocks, with slight inclinations
in various directions in which the streams and rivers would begin to flow, when the
whole had been elevated into land. Out of such a gently undulating plain the
physical features of Ireland were probably sculptured: the rivers collected and
carried off the débyis; the softer Carboniferous rocks, which offered such favourable
conditions for the wasting forces to act upon, began rapidly to disappear; and the
purer limestones below, once reached, were quickly dissolved in the rain-fed waters
of the streams, leaving the harder Old Red and Silurian rocks standing out in bold
ridges, their relative elevation due not so much to any forces of upheaval, as to the
comparatively greater destruction and removal of the adjoining strata. To estimate
the full power of such forces, we must attempt to form some idea of the time during
which they were in operation, and here we must recall the fact already noticed, that
in Ireland there is no representative (in the portion occupied by the great central
plain of which the author is speaking) whatever of the Mesozoic, or older Cainozoic
rocks, and that the only satisfactory cause of this absence, when they are so largely
- and fully represented in the adjoining island, is that they never were deposited in
Treland, or, in other words, that, during the long period represented by their for-
mation, part of Ireland was above water, and was subjected to all the destroying
forces which can only act energetically on dry land. ‘If this be so,’ Prof. Hull
eloquently says, “ how vast was the lapse of time during which this portion of the
British Islands was being subjected to the wasting influences of rain, rivers, and
other subaerial agents of erosion! During this time the Permian beds, with their
varied deposits of sandstone and limestone, stored with marine fossils, were de-
posited; the great salt lakes of the Triassic period were constructed; successive
generations of Saurians, Molluscs, and other marine forms flourished and passed
away during the Liassie stage; great beds of Oolitic limestone, now rising into
mountain ridges along both sides of the central axis of the Alps, and composed
almost entirely of the shells and skeletons of marine organisms, were laid down over
the floor of the Jurassic sea. Then followed in succession subaerial, lacustrine and
estuarine conditions, which at length gave place to fresh submersions under the
ocean of the Cretaceous period, during which masses of limestone, many hundreds
of feet in thickness, were constructed by the ceaseless industry of lowly-organized
marine animals, chiefly Foraminifera. To these the varied deposits of the Tertiary
age were superadded, and over the south of Europe, along a zone extending from
the countries bordering the Mediterranean to the frontiers of China, the Nummulite

1 The wording of the book under review might here give rise to an erroneous
idea, which however we do not think the author intends to convey. ‘‘ He says, ** The
extensive peat mosses . . . . are a still more recent covering (of the limestone), and
generally occupy the positions of former shallow lakes” (p. 157). This would imply
that they occur resting immediately on, or forming a direct covering to the lime-
stone—in reality, we believe they never do, They occupy shallow lake-like depressions
in the clays, a thin deposit of calcareous marl with fragments of shells marking the
lacustrine deposits at their base, before the growth of vegetation converted the pool
into a moss, or bog. We believe it scarcely possible for such a peat moss to be
formed upon an open and highly porous base, such as the limestone itself would
afford. :

Reviews—Prof. Hull’s Physical Geology of Ireland. 169

limestone, the greatest limestone formation in the world, was built up mainly of the
coiled shells of a special group of Foraminifera, the Nummulites. ‘Throughout this
inconceivably long lapse of time our island was more or less unsubmerged, its surface
being swept by subaerial waters, and its strata carried little by little into the adjoin-
ing ocean, to form perhaps some of the strata which were being piled up over the
ocean bed of the British area.” !

The origin of the river-valleys next claims attention. And here the views of
Jukes, Ramsay, and others are fully endorsed in accounting for the frequent
occurrence of such facts as that rivers cut through bold escarpments of hard rock,
which, at first sight, would appear certain to have barred the course of the streams.
It is thus argued that the course of the river Shannon, the largest river of Ireland
(where, for example, it cuts through the high ridges marked on either side by the
hills Sheve Bernagh and Slieve Arra, through which gorge it now flows, apparently
in preference to taking comparatively much lower ground, and an easier course, to
Galway Bay), is really due to the fact that when the river first took this channel, the
ground now forming these ridges of mountains was in reality somewhat lower than
the ground to the north of it, now part of the plains. And the river, having once
commenced cutting out its channel, has never since abandoned that course, but has
gone on gradually lowering its valley, till the wide gorge, through which it now foams
in its rapids and falls, resulted. Reasoning of a similar kind is applied to the cases
of the Blackwater, the Lee, etc.; but here Prof. Hull, most justly as we think, brings
in also the consideration of other physical causes, and argues that in such cases, where
not only do the rivers cut across ridges of harder rocks, but, to do so, divert their
course nearly at right angles to their general direction, there must have been some
disturbance at or close to the point of divergence; and in the two cases noticed he
appeals to the existence of lines of fault at these localities, which have naturally had
a tendency to divert the water-course. We are glad to see this open acknowledg-
ment of the influence of such forces, which have been, we think, too much ignored
of late years.

Passing over the notice of some ‘old dried-up river-valleys,”’ as the author calls
some gorges, which have obviously been originally cut out by running water, but
which now have only trifling little streams trickling through them, or are dry, we
come to the Lakes of Ireland. These are divided into three classes—(1) Lakes of
Mechanical origin—(2) Lakes of Glacial origin—(3) Lakes resulting from Chemical
solution. These lakes in Ireland are very numerous and extensive, covering a very
large area of the country. Pre-eminent among them is Lough Neagh, the largest
lake in the British Isles. This Mr. Hardman? has shown to be of Post-Miocene age,
perhaps Pre-Pliocene, and Mr. Hull adopts the views of this valuable paper. They

J

1 We regret that we are compelled to think that Prof. Hull has very seriously
injured the effect of this telling paragraph by the concluding sentences. It is so
seldom that we find any attempt at what might be called forced oratory or over-
strained sentiments in Mr. Hull’s matter-of-fact writings, that any departure from
good taste in such a direction makes the stronger impression. The danger of using
terms and expressions derived from and only applicable to intellectual beings, and
their rational acts, in explanation of inorganic forces, has often been insisted on,
and has here also proved to be the origin of the pseudo-scientific and false analysis
of the writer. It may be perfectly true that part of the material removed from the
surface of Ireland was thrown down in the British area, and may so far have contri-
buted to the future mineral wealth of England. But when he speaks of Ireland
‘stripping herself to clothe her sister,” ‘‘and to supply materials for protecting from
atmospheric waste her vast stores of Coal, upon which her greatness and prosperity
now so largely depends;” and even goes on to exclaim ‘this debt ought never to be
forgotten”’—the writer only excites the smile of geologists and the wondering stare
of others. We should not wonder, to carry out the idea further, if some of the
modern Home Rulers would threaten to bring an action to recover compensation for
the loss incurred by their country (countless ages before man existed at all) by this
reckless sacrifice to England ; while on the other hand we have little doubt that some
of those who are now harassed and vexed by the obstructiveness of modern patriots
would be glad to see a little continuance of the former generosity on the part of

Ireland towards her poor sister, in these sadly degenerate days!! We cannot too
strongly reprobate such mischievous and false attempts at sentimentality in scientific
questions.

2 Gear. Mage. Vol. III. Dec, II. p. 556; Journ. Roy. Geol. Soc. Irel. vol. iv.
p. 170.

170 = Reviews—Prof. Hull’s Physical Geology of Ireland.

think the river, which flows into the lake from the South, took its course along the
general depression caused by a disturbance of the great Miocene basaltic sheets, and
which general depression or bottom of the basin of the volcanic country has been
already noticed ; and was pent up into a lake by some of the faults, which cross the
area of the lake, and some of which have considerable downthrow to the north,
corresponding in position with the greatest depth of the lake. This older lake was,
as already noticed, of much greater size than the present one—which has gradually
retreated, as its barrier was worn down. ‘The lake therefore is considered to be
chiefly a basin of submergence formed by the mechanical action of faults in the
strata forming its bed. Although it is said that this origin of Lough Neagh is
‘wholly exceptional’ (p. 198), Lough Allen seems, according to the author’s views,
to be due to very similar causes. ‘This noble lake forms a great reservoir for the
head-waters of the Shannon. It fills a wide valley, the banks of which are formed
of the Yoredale rocks and the floor of Carboniferous Limestone, and the formation of
the lake is attributed to the production of a barrier across its lower end by a large
fault, heading K. 20° N., with a downthrow to the north. This fault brings the
Carboniferous Limestone on that side down against the Silurian and Old Red rocks,
and has thus had precisely the same effect which an artificially raised barrier would
have in converting the river-valley above into a lake. This barrier has been con-
siderably worn down and lowered since its formation, but it still retains a relative
elevation as compared with the floor of the lake, and so, of course, the lake remains.
There is no distinct evidence of the age of this faulting, but the author points out
that its direction is very similar to the direction of the faults which have, as stated,
produced Lough Neagh. And he thinks it not improbable that it was really pro-
duced about the same epoch—that is, between the Miocene and Pliocene.

With regard to lakes of Glacial origin, there are said to be two ways in which
these forces have acted: 1. by actually scooping out rock-basins, and 2. by de-
positing moraines, heaped up across a valley or hollow, and thus pending up the
waters of the stream flowing along the depression above. Of both these varieties
numerous instances occur in Ireland, though none of any great size. In places they
form regular networks of little loughlets and rock-basins. The author also thinks
that the wide shallow lakes of the central plain of Ireland owe much of their extent
and form to the action of ice, although they are principally due to another cause.
After “giving several well-marked cases of moraine-dammed lakes (Lough Bray,
Lough Nahanagan, etc.), he passes to lakes of Chemical origin. ‘To enumerate all
the lakes of the great central plains of Ireland would be a useless waste of space.
All have one common character, they are all irregular hollows and depressions in the
general limestone floor, now filled with water, and these depressions and hollows are
principally due to the solvent action of the water on the limestone rapidly eating
into it, and removing it in solution. Some of these lakes are intimately connected
with large underground rivers, the channels of which have been in a similar way
dissolved out of the limestone. These give rise to lakes and fountains, the true
source of which is often not traceable at first. Similar forces of solution and denu-
dation have in many cases produced the deep indentations which abound round the
coasts of Ireland, in the limestone districts, and which, subsequently filled with
glaciers and scored, and scooped out, passed into the state of ‘‘ fiords.”

The third part of Prof. Hull’s work is devoted to the ‘“ Glaciation of Ireland.”
And here we would first direct attention to the very effective and well-executed little
map of the ‘‘ General Glaciation” which is given. Itis an admirable example of
how much can be compressed into a small space with perfect legibility and clearness.
Starting with the assumption that it has been generally recognized that the surface
of the solid rocks of Ireland is widely and extensively glaciated, and that an ‘‘ice-
sheet’”’ covered the greater portion of the country, Prof. Hull bears willing and
just testimony to the value of the labours of the Rev. Maxwell Close, and proceeds
to discuss the essential differences between General glaciation and Local glaciation,
one being antecedent to the other, and of much wider extent. Then adopting this
division of the subject, he notices each separately, both being said to “have left their
traces on the rock-surfaces in the form of polished and moulded bosses, scars, delicate
chisellings, or deep groovings often intersecting each other at various angles, and
requiring care and some amount of general knowledge of their causes, in order
to distinguish to which period of glaciation they belong”’ (p. 212). Mapping out
the lines of scoring at the bottom of the Lower Boulder-clay has determined the
general nature of the ice-movement, and has shown, as our author believes, that it

Reviews—Prof. Hull’s Physical Geology of Ireland. 171

‘belongs to one grand dominant system of central pressure, which has caused the
ice to move outwards in all directions from a central snow-field towards the existing
coasts, except where impeded or deflected by local mountain barriers.” After point-
ing out the reasons for admitting that such markings were caused by ice-borne
materials, and the several indications afforded by polished rocks, ‘crag and tail’
forms, boulders, and their positions, of which numerous instances are given,' he
proceeds to discuss the laws regulating the movements of this great ice-sheet, ‘ of
the existence of which there can be no doubt whatever.” He points out, and adopts
entirely the conclusions of Mr. Close, that the movements of this ice-sheet have
proceeded in opposite directions seawards, from a line or tract of country, stretching
in a belt across the island, occupying the country between Lough Corrib and Lough
Mask on the west and Lough Neagh on the east, thus stretching for a distance of
more than one hundred miles from W.S.W. to E.N.E., from which tract, as
from an axis of motion, the ice has passed both north and south. The position
of this supposed axis is well shown on the little glaciation map to which we referred,
This very remarkable conclusion of Mr. Close is particularly noticed as differing
from what is already known in any part of the world with which we are acquainted.
Jn every other known case of such distribution of glacial motion from an axis or
centre, those centres have been districts of greater elevation than the country adjoin-
ing. The Alps, the Pyrenees, the great elevated Scandinavian highlands, the
Snowdon range in Wales, the Cumberland and Westmoreland ranges in England, the
Grampians and the Southern highlands in Scotland, are all well-known instances of
this. But in Ireland no part of the axis of movement is more than 400, or at the
outside 500 feet, above the sea-level, while it is stated, as a positive and admitted
fact, that from this an ice-sheet has been set in motion, which has not only topped
and completely passed over such little minor obstacles, as, for example, the Coal-fields
of Castlecomer, etc., which rise to 700 feet, but has overrun hills of more than
1000, or even 1500 feet, and has been forced up the flanks of higher mountains to
still greater elevations. It is, therefore, only right that the propounders of such a
theory. should endeavour. to explain the actions which took place. Mr. Close
suggested that the country had been more elevated over the land now occupied by
the counties of Mayo and Roscommon than more to the south and east. But Prot.
Hull rejects this as quite an insufficient cause, inasmuch as the movement has not
taken place merely from a central point, or from the western end of the axis alone,
but along a line of more than 100 miles. And he has no hesitation in suggesting at
once a different explanation. He says (p. 229), ‘‘Is it not conceivable that the line
of country here described was at the earliest glacial period the region of greatest
snowfall—the region of greatest precipitation of snow, as it is now that of greatest
precipitation of rain?’’2 He supposes that the snows were piled up over this belt of
country to an ‘enormous’ depth, and to a less extent over the tracts lying to the south
and east, until the vertical pressure of ‘ thousands of feet’ of snow and ice there
accumulated was converted into a lateral pressure, forcing the ice to move in a
direction towards the points where it could find an outlet. After expressing his con-
fident belief that the vertical pressure of this ‘enormous’ pile of ice and snow
gave the first initial movement to the ice-sheet, both southwards and westwards,
Prof. Hull still confesses that we are obliged to have recourse to other modes of
explanation of the facts that this motion has been propagated to upwards of one
hundred miles from its source, and that it has caused the ice to move, not only over
plains, but up the sides of opposing hills and ridges. And to this end he is disposed
to adopt a development of Charpentier’s dilatation theory, as explained by Dr. Croll.
This, in general, is, that the internal pressure resulting from the solidifying of the
fluid particles of water which has filled the interstices of the ice, acts on the mass
as an expanding force tending to cause the glacier to widen out laterally in all direc-
tions, and the author adds—‘‘to move with a linear motion in the line of least
resistance,’ but he does not attempt to show that the direction of motion of the ice-

1 We do not observe any notice, among the detailed descriptions of the drift deposits
of Ireland, of the important fact of the occurrence of pieces of the compact Creta-
ceous limestone of the N.H. of Ireland in the clays of the South of Ireland, even so
far south as the County of Cork.

2 The writer adds most naively in a note, ‘‘Of this, however, I have no positive
proof,” no general returns of rainfall being available, but he says, ‘‘I have little
doubt that it is the case.”

172 = Reviews—Prof. Hull’s Physical Geology of Ireland.

sheet, as supposed to be proved by the scorings, etc., would be that line of least
resistance. A large mass of details of these scorings is given, filling more than
twenty pages—but these the student must consult for himself. The thickness of the
great ice-sheet is held to have been at least 1000 feet, probably much more.

The existence of local centres for glaciers towards the close of the glacial period,
after the submergence of the plains and the general re-emergence of the land again,
is then noted and some details given; and the volume then concludes with a very
brief chapter ‘“ connecting the pre-human with the present age,” a chapter which in
future editions we hope to see vastly extended.

In reviewing the author’s conclusions as a whole, there are only
a few points which appear to call for any special notice. One of
these is the much greater prominence which Mr. Hull has given
to the agency of chemical solution, in the production of physical
results, than has been generally acceded to it. In a country where
limestone originally formed such a very large portion of the exposed
surface, it was only natural to find evidence on a great scale of this
action, and we gladly direct attention to the valuable observations
of the author on this point. In another direction also, that is, in
the fuller application of the effects of terrestrial disturbances as
causes of the present physical features of the country, we think the
author’s views worthy of commendation. There has been of late
years too great a tendency to push to extremes the application of
some pet theories, till almost the very existence of other forces has
been ignored—and we are glad, therefore, to see the influence of
faults, and of deepseated disturbances, again appealed to, and
restored to its legitimate position in the sequence of formative causes.
The wide application of ice forces in their varied exhibition was of
course to be expected. The pages of this journal for years have
been so filled with valuable and detailed contributions to these
inquiries, that our readers are fully prepared to admit the importance
of this branch of geological research, and to accept many of the
conclusions which have been adopted. But, at the same time, the
very nature of many of these contributions to which we have re-
ferred suggests to every sound thinker, as we believe, the necessity
for great caution and watchfulness before admitting any new hypo-
thesis, however boldly or dogmatically it may be propounded, either
as a speculation, or possibly, even, asa fact; for there are many cases
in which this, too, has been done. In the analysis of the author’s
views which we gave above, we have endeavoured to state them
with clearness and sufficient fullness to make them intelligible. pre-
ferring to leave them for the most part as the opinions of the writer
only, and not to discuss them as geological views or doctrines.
But we would not be justified in altogether passing over in this
way some of these views. With reference to the “General Glacia-
tion of Ireland,” a conclusion worked out by the Rev. M. Close, as
to the axis or origin of motion of the ice-sheet over the island at
the earlier part of the great glacial period, is unhesitatingly adopted
by our author; and he proceeds at once to propound—and in terms
which lead his reader to suppose that the whole thing was obvious
to the smallest consideration—a solution of this anomaly. He
supposes that snow and ice were heaped up over a belt of low
ground extending more than 100 miles in length, and, say, ten in

Reviews— Prof. Hull’s Physical Geology of Ireland. 173

breadth—to an ‘enormous’ extent, ‘thousands of feet’ in depth,
etc., so as to give the pressure which he thinks needful to have
originated this general outward motion in both opposite directions
from this axis. We should greatly have wished that he had given
us some idea of the actual physics of such a heap of snow, ‘ thou-
sands of feet’ in depth, perfectly unsupported on either side by any
more solid materials—or had shown the probability even of this
extreme accumulation which he supposes to have taken place over
this belt of country, ever amounting to such a differential excess as
to give him the required depth of ice."

But is this idea of Mr. Close’s so thoroughly established that we
are driven to the region of wild fancy to attempt an explanation of
it? An immense mass of detail is referred to by Prof. Hull in
evidence of this supposed movement of the ice-sheet (pp. 286-259),
but all this evidence must be carefully analysed before we can
admit its conclusiveness. And the author must permit us to doubt,
and to doubt very seriously, if a great part of it is applicable to the
point at issue at all. He himself, and equally every other writer of
these glacial theories, insists on the necessity for ‘experience,’ and
a certain knowledge of the causes of these markings, scorings,
polishings, etc., appealed to as evidence of the movement, before the
observer can appreciate their force or value. And firstly it is urged
that in such matters we should take our lessons from the existing
centres of glacial action, such as the Alps, Norway, and Greenland.
How far has this been done? How many of the dozens of observers,
whose notes have been culled, have studied these glacial phenomena
in their existing centres? How many have been capable of dis-
tinguishing, or have attempted to distinguish,—or have even known
the necessity of such an attempt,—marks of local glaciation from
those due to the supposed general movement? And if the whole
mass of evidence adduced be subjected to such a searching analysis,
how far will this idea of a linear axis of motion remain established ?
We confess we hesitate much before we can admit it. Our author
himself adds greatly to our feeling of the necessity for great caution
in such matters. In this way (at p. 115), speaking of “ River
Terraces,” the most recent of the “Drift” deposits, he says :—

“ Of these the most remarkable and interesting from its historical and architec-
tural associations is the terrace at the lower end of Glendalough, at its confluence
with the vale of Glendasan, upon which stands the Round Tower, and the Church of
St. Kevin. ‘This terrace is composed of stratified gravel of rounded pebbles and
sand banked up against an old moraine which has been thrown across the valley.

The upper surface is level and it rises about twenty feet above the bed of the Glen-
ealo River.”

Now if we turn to p. 197, we find that—

“* After careful examination I have also come to the conclusion that the Round
Tower and Churches of Glendalough are built on a moraine, which has been thrown

1 Old Procopius held that on the tops of high mountains there never fell either
snow or rain, because they are above the highest clouds!! Bacon, in one of his
wonderfully sententious passages, says, ‘“ Adulterina res est in scientiis preecocem
esse et promptum, nisi etiam solidus sis et multipliciter instruetus.”—De Augm.
Scient., lib. v. cap. v.

174 Reviews—Prof. Hull’s Physical Geology of Ireland.

across the Glendalough valley by the glacier that descended the vale of Glendasan.
This moraine had originally pent up the waters of the lakes, and against its northern
flank the old terrace of gravel (described in another page) has been deposited.
Afterwards the river cut down its channel and lowered the level of the waters. In
this view Professor Ramsay concurs.”

Here the question naturally occurs—Is the Round Tower and are
the ‘Seven Churches” at Glendalough really built on a moraine, or
on a river terrace? Nothing is more probable than that a terrace—
not however a river-terrace—should have been deposited against the
flank of a moraine damming up a lake. But this is not the point
here. If in so accessible, and so easily examined and well-marked
a locality as Glendalough, it required careful re-examination, and the
aid of Prof. Ramsay, to find out that the foundation of the Round
Tower was placed, not on a river-terrace, nor even on a terrace, but
on a moraine (the two being of totally different ages, and due
to totally different causes), we are compelled to think that there
must still hang a thick mist of doubt and uncertainty over very
many of the thousands of observations of glaciation phenomena
which have been recorded. Nor is it within the just limits of ex-
pectation to hope that we shall find every one as open to conviction,
and as ready to acknowledge error, as Prof. Hull has shown himself
to be. Until, however, these doubts be removed, we can have no
knowledge of the facts—for, as the Stagyrite says, “knowledge is
the solution of doubts.”

We have felt the want ourselves, and, therefore, do not hesitate
to notice it, as it possibly may be supplied in future editions, of a
little more aid to the imagination of the reader, by appeals to his
eye. The general features and scenery of parts of Ireland are
familiar enough to many, but even of those who know such scenery
in detail, how few have realized the general character of the outline,
or its essential dependence on the structure of the rocks below.
Geologists will remember gratefully the vast aid which they derived
in framing a general conception of the S.E. of Ireland from the
admirable panoramic sketches of Weaver (Trans. Geol. Soc. Lond.
1st series, vol. v.). But we would refer to far more recent, and far
less costly, illustrations of this kind in the many valuable publica-
tions of the Geological Survey of the United States Territories
under Prof. Hayden. Some of these, though almost pure outline,
convey the most wonderfully clear and accurate idea of the structure
of the country represented, and of the intimate dependence of its
physical features on that structure. And if a few such general
outlines of the more marked centres of interest in Irish scenery
and Irish geology could he given, we have no hesitation in thinking
that the book would commend itself to a far wider circle of readers
than it is likely at present to command.

The British Association meet in the capital of Ireland in the
coming autumn, and there is every prospect that a large concourse
of visitors will then be attracted in addition to the ordinary crowd
of visitors. ‘The well-known and generally appreciated hospitalities
of Dublin, the loveliness of the scenery of the country, and the

Reports and Proceedings—Geological Society of London. 170

facilities afforded for numerous excursions, will all offer in-
ducements to the hundreds of strangers who will then visit the
‘Land of the Giant Deer, and the Giant’s Causeway.” And to
each and every one of these we would say, Make yourself acquainted
with the facts detailed in Prof. Hull’s ‘“ Physical Geology and
Geography of Ireland,” and so well acquainted that you can realize
those facts, and be able to trace the broad features in the succession
of events which have produced the present features of the country.
Then, whether you tarry in pleasant dalliance over the lovely
scenery of Killiney and Bray, or stray in softened mood among the
richly wooded beauty of the Dargle or Ovoca, or seek the wilder
loneliness of some of the more distant glens of Wicklow or Galway,
and stand awestruck and silent before the deeper secrets of Nature’s
revealing, or whether you visit “that most delightful spot in the
British Isles,” and contrast the luxuriant fertility and astounding
richness of colouring of the lakes and islets and woods of Killarney
with the weird savageness of the Gap of Dunloe, or the lonely gloom
of the Black Valley, you will derive a deeper and a more lasting
impression of the beauties of all, if you bring to this examination
a previous acquaintance with the general causes of all the varied
features of the country, and with the history of the successive steps
in their production. And, in this view, we confidently hope that
Prof. Hull’s excellent summary will prove remarkably well timed
and successful.

ASV IS OlSyS JNANTAD) IJS=sR(OCGs aD IAN eS

Ss —

GerotocicaL Socrery or Lonpon.—I.—February 6, 1878.—Prof.
P.M. Duncan, M.B., F.R.S., President, in the Chair.—The following
communications were read :—

1. “On some Foraminifera from Pleistocene Beds in Ischia.” By M. Ernest
Vanden Broeck. Preceded by some geological remarks by A. W. Waters, Esq., F.G.S.

In this note Mr. Waters referred to certain fossiliferous deposits occurring at
various elevations in the island of Ischia, the oldest being a clay found up to 1800
feet on Monte Buceto, whilst the others may be classed with raised beaches. These
deposits have been already noticed by Sir Charles Lyell, who obtained from them
twenty-eight species of shells, all, with one exception, identified by Deshayes with
recent species. M. Fonseca has given a list of ten species of shells from the Buceto
beds, and to these Mr. Waters has added ten more, all now living in the neigh-
bouring sea. A portion of marl forming the matrix of one of these shells was sent
by Mr. Waters to M. Vanden Broeck, who found in it twenty-seven species of
Foraminifera, with respect to which he remarks that this fauna has a more recent
facies than that of the true Subapennine deposits, all the species being now living
either in the North Atlantic or Arctic Ocean, and nearly all in the Mediterranean.
The presence of Zagene and of some other forms, however, indicates closer relations
with the northern oceanic fauna than with that of the warmer Mediterranean. The
Foraminifera from Ischia are generally of small size, probably indicating unfavour-
able conditions. The deposit containing them was probably formed in not very deep
water, and more recent than the true Subapennine deposits; and the small size of
most of the specimens, and the predominance of northern forms, would seem to show
that the deposit took place when the refrigerating influence of the glaciers was
beginning to be felt.

2. “On the Influence of the Advent of a Higher Form of Life in modifying the
structure of an older and lower Form.” By Professor Owen, C.B., F.R.S., F.G.S.

176 _ Reports and Proceedings—

In this paper the author, after referring to the general question of the modification
of the structure of organic forms produced by the action of external influences, indi-
cated that, in connexion with this, changes in the nature of the prey of carnivorous
animals ought to be taken into consideration. He inferred that cold-blooded aquatic
animals formed a much greater proportion of the food of Mesozoic than of Neozoic
Crocodiles, and pointed out as connected therewith the well-marked distinction
between the amphiccelian and proccelian type of vertebree respectively characteristic
of the two groups. The proccelian character of the trunk-vertebre better adapts
that part of the body to be sustained and moved in air, and may be connected with
the incoming in Tertiary times of mammalian prey inducing the Crocodiles to rush
on shore. ‘lhe Mesozoic Crocodiles were encased in a much stronger and more com-
plete dermal armour than their successors, doubtless for their protection from the
great Ichthyosaurs, Pliosaurs, ete., which coexisted with them; but as these passed
away at the close of the Secondary epoch, the armour of the proccelian Crocodiles
has become more scanty, and the diminution of weight and rigidity thus caused would
favour progression in air, and the rapidity of movement required for capturing mam-
malian prey on land. The difference in the position of the palato-nares, and in other
related gular and palatal structures, between the Mesozoic and Neozoic Crocodiles, is
apparently connected with the power possessed by the latter of holding submerged a
powerful mammal without permitting the access of water to the posterior nostrils and
windpipe of the Crocodile; and hence the author is inclined to ascribe a fish-diet
even to those massive-jawed Crocodiles from the Purbeck (such as Goniopholis crassi-
dens and simus), which in some respects might seem fitted to grapple with large and
active mammals. The small size of the upper temporal apertures in Tertiary and
existing Crocodiles is regarded by the author as a further proof in the same direction ;
these apertures are reduced by the progressive increase of the osseous roof of the
temporal vacuities, which again is correlated with increase in the bulk and power of
the temporal muscles, the main agents in biting and holding. The differences in the
length and strength of the jaw, as a rule, testify in the same direction. Further,
the fore-limbs in Mesozoic Crocodiles are shorter than in Neozoic species, indicating
that the former were more strictly aquatic in their habits; the fore-limbs in all
Crocodiles being closely applied to the body during rapid swimming, and small limbs
being less obstructive than larger ones. On the other hand, they would be less
efficient as a means of progression on land, and hence it may be inferred that the
advent in Tertiary times of mammals frequenting the water-side, tempting the
Crocodiles to make a rush upon the land to seize such passing prey, would lead to
such strenuous action of the fore-limbs as would account for the increased size and
power of those organs in the Neozoic species. The author concluded with some
remarks upon the influence of the above considerations upon our views as to the
generic divisions of Crocodiles.

3. ‘Notes on a Crocodilian Jaw from the Coral Rag of Weymouth.” By E.
Tully Newton, Esq., F.G.S., of H.M. Geological Survey.

In this paper the author described what he believes to be a fragment of the lower
jaw of a Crocodilian, obtained from a greyish brown sandy grit, probably belonging
to bed 3 of Messrs. Blake and Hudleston’s Sandford-Castle section. The specimen
measures about 11 inches long, and includes portions of both rami. The right ramus
contains the remains of 12 alveoli, some of which, notably the first, second, fourth,
and fifth, contain fragments of teeth, which appear to have been directed very
obliquely outwards and forwards. The portion of the left ramus preserved gives
indications of 14 or 15 teeth. An impression of a tooth in the matrix gives a length
of 1+ inch for the crown of the larger teeth; their section was nearly round; but a
young unused tooth is slightly.compressed, with a distinct ridge running down each
side and two smaller ridges on the inner surface. The general surface of the crown
was covered with fine but distinct longitudinal ridges. The median area has a spindle-
shaped portion separated from the rest by deep grooves, the surface of which is longi-
tudinally grooved; and this character, according to the author, does not occur in
either of the genera mentioned by M. Deslongchamps.

4. “Note on Two Skulls from the Wealden and Purbeck Formations indicating a
new Subgroup of Crocodilia.” By J. W. Hulke, Hsq., F.R.S., F.G.S.

The author described a Crocodilian skull obtained by Mr. H. Willett, F.G.S.,
from the Hastings Sands near Cuckfield, in Sussex, and identified by that gentleman
with Goniopholis crassidens, Owen; and another from the Purbecks near Swanage,

Geological Society of London. Y Dbiee

in the collection of the British Museum; which he further compared with a third
specimen from Brook, in the Isle of Wight. He had little doubt that Mr. Willett’s
specimen had been correctly identified, and thought it and the Brook skull were
probably specifically identical. All these skulls belong to a group intermediate
between the Mesosuchia and Eusuchia of Prof. Huxley. In the constitution and
position of the palato-nares they most nearly resemble Metriorhynchus Blarnvillit,
Desl., among the Mesosuchia. The general contour of the skull resembles that
prevalent in the typical Crocodiles, such as Crocodilus rhombifer. In the arrest of
the nasal bones short of the anterior nares they rather resemble Gavialis, and still
more the Bornean Rhynchosuchus Schegelii, as also in the form of the palato-nares.
From the combination of characters presented by these Crocodiles (which the author
regards as representing two species of Goniopholis) and their geological age, the
author proposes to place them in an intermediate subgroup, which may be designated
Meta-Mesosuchia.

TI.—Annvat GreneraAL Murtine.—February 15th, 1878.—Prof.

P. Martin Duncan, M.B., F.R.S., President, in the Chair.

The Secretaries read the Reports of the Council and of the Library and Museum
Committee for the year 1877. The Society was described as in an exceedingly
prosperous condition, and the income of the year was stated to have considerably
exceeded the expenditure. The number of Fellows elected was fully up to the
average. The Report further announced the receipt of a bequest of £500 under
the will of the late C. Lambert, Esq., which sum, with £150 of the surplus of income,
had been invested in Consols for the benefit of the Society.

In presenting the Wollaston Gold Medal to Dr. Thomas Wright, F.R.S., F.G.S.,
the President addressed him as follows :—

Dr. Wright,—It gives me very great pleasure to present this Medal to you, and
to know that your name will be enrolled amongst those of the many distinguished
men who, like yourself, have earned this distinction by long and successful labour in
geological science. Your careful paleontological work amongst the Echinodermata
of the Secondary rocks of England has been as interesting and important to those
paleontologists who have followed you in the study, as your description of the
Maltese Echinoidea. You have not only collected, but have described carefully
some of the most important Mesozoic corals, and have clearly distinguished the
succession of some local coral reefs in the British area. Your stratigraphical labours
amongst the Rhietic, Jurassic, and Oolitic formations have Jed to excellent results.
Your classification of the great groups of Echinoidea has stood the test of time, and
is still employed; and the description and analysis of the species, illustrated so
exquisitely, in the volumes of the Palzontographical Society, are models of terse
exactitude. Your determination of the correct relation of the madreporic body to
the antero-posterior axis of the Echinoid has been accepted by nearly every
naturalist, and its bearing on the elucidation of the meaning of the apical system of
the Salenide is of much importance. The Council considers that your industry and
the excellent results of your study establish your claim to this Medal, and I hope
that its reception will not only stimulate you to further research, but will reward you
for the sacrifices that every man who combines a scientific and a professional career
has to suffer.

Dr. Wright, in reply, said :—Mr. President,—I am deeply sensible of the very
great honour the Council of the Geological Society has conferred in awarding me the
Wollaston Medal, and I beg to return my most heartfelt thanks for their apprecia-
tion of my humble labours in paleontological studies. To be enrolled in the list of
eminent men on whom this great distinction has been conferred is a position of which
the most ambitious may well be proud, whilst the graceful and eulogistic phrases
with which you, Mr. President, have conveyed the award, and the friendly greeting
I have received from Fellows assembled here to-day, have all touched me exceed-
ingly, and I can find no language adequate to express the sentiments of gratitude I
experience on this occasion. It is at all times a pleasure to receive from our con-
temporaries working on the same line with ourselves a friendly estimate of our
honest endeayours, but when the Council of this great Society, which counts among
its Members some of the most learned masters of Geological Science, bestows its
highest award as an acknowledgment of the worth of my scientific work, I confess
how much indeed I appreciate the distinction, and how highly I value the prize.

DECADE II.—VOL. V.—NO, IV. 12

178 . Reports and Proceedings—

You have kindly informed me that the Wollaston Medal has been awarded as
a recognition of my detailed researches, continued through many years, on the
structure, classification, and distribution of the fossil Echinodermata, published by
the Palzontographical Society, and for other memoirs on the Jurassic and Tertiary
strata of England. If my lite is spared, the event of to-day will become a stimulus
to renewed exertion in that path of scientific study in which I have plodded for
the last thirty years. As much of that work has been carried out by the Paleonto-
graphical Society, perhaps you may allow me to say how much I consider the progress
of Geology has been advanced by the splendidly illustrated volumes it has published.
They form, indeed, a magnificent monument of unpaid voluntary effort in the cause
of Science.

Let us never forget that much of the knowledge we have acquired in our re-
searches concerning the mineral structure of the earth is due to Paleontology, and
that the future of Geology will largely depend on its onward progress. The accurate
description of organic forms, their true position in time, and distribution in space is
the important province of Paleontology to determine; and by correctly translating
the archeology of organic nature into the pages of geological literature, the paleon-
tologist may hope to solve some of the great questions that distract the naturalists of
our day, and enable them to read aright the changing conditions under which life
existed during vast periods of past time.

The President then presented the balance of the proceeds of the Wollaston
Donation Fund to Mr. W. J. Sollas, M.A., F.G.S., and addressed him as follows :—

Mr. Sollas,—I have great pleasure in handing you the Balance of the proceeds of
the Wollaston Donation Fund in recognition of your careful morphological and
mineralogical studies upon the fossil Spongida. ‘The Council of this Society is
impressed with the belief that you will continue to benefit paleontological science
by your researches in those Amorphozoa which, up to a recent date, were compara-
tively unknown, or whose anatomical characters were misunderstood. Having made
an excellent beginning, of a great course of investigation, you will, I trust, be
stimulated to perseverance and exactitude by this testimony of the good wishes of
this Society.

Mr. Sollas replied:—Mr. President,—I beg to express my thanks to the Council
for their award, and to you, Sir, for the encouraging words with which it has been
accompanied. Next to the pleasure of discovering something new, and of adding
something to the common store of knowledge, I can conceive of no greater gratifica-
tion than the appreciation of one’s fellow-workers, and the approbation of those
whom I am proud to regard as my masters and teachers in Science. ‘The study of
the fossil sponges presents us with a true El Dorado of research, to which the way
has been clearly opened by the labours of those distinguished spongiologists Bower-
bank, Oscar Schmidt, and, lastly, Carter, of whom I hope I may be allowed to say
that he is facile princeps. It will now be my duty, as it is my pleasure, to attempt
to make use of this “‘ way,” to apply the facts which have been discovered concerning
the structure of the living sponges to the interpretation of the sponges of the past,
and I trust that in this endeavour I may meet with such a measure of success as
shall prove that I have not been an unworthy recipient of the confidence reposed in
me to-day.

The ender next handed the Murchison Medal to Mr. Warington W. Smyth
for transmission to Dr. Hanns Bruno Geinitz, of Dresden, and spoke as follows :—

Mr. Warington Smyth,—The Council of the Geological Society has awarded the
Murchison Medal to Dr. Hanns Bruno Geinitz, Professor of Geology in the University
of Dresden, for his researches in the geology and paleontology of the Paleozoic and
Cretaceous formations of Saxony. For forty years at least Dr. Geinitz has been an
assiduous cultivator and promoter of Geological Science. He has especially devoted
his attention to the study of the Permian formation, and has greatly increased our
knowledge of its fauna and flora. The general differences of the Permian and
Carboniferous floras have been pointed out by him in his work on the Permian plants
of Saxony. His first essay on the Zechstein was in 1838, and subsequently he wrote
on the ‘‘ Grauwacke formation,” which included the Silurian, Devonian, and Carboni-
ferous strata of Saxony. The Cretaceous formation of the same country also received
his attention. A friend of, and co-worker with the donor of this Medal, he not only
assisted him in his labours, but was occasionally his companion whilst investigating
the more interesting localities around Dresden, services which are acknowledged in

Geological Society of London. a Lng

the work on ‘‘Siluria.”” Dr. Geinitz has contributed many other important works
to our science than those which the Council consider to be the most meritorious, and
it therefore is a privilege that I should be able to ask you to convey to our old and
much esteemed Foreign Member this Medal, which, I am sure, he will appreciate.

Mr. W. W. Smith replied :—I have much satisfaction in receiving from the hands
of the President for transmission to Prof. Geinitz the Medal awarded to one who has
done so much to advance our knowledge of Central Germany. I have received a
letter from the Dresden Professor, in which he states that he is deeply touched at
being in this way again associated with the name of his old and venerated friend
Sir Roderick Murchison, that he regrets being unable to attend this meeting,
but begs to assure the Society of his high appreciation of the honour, and of his
intention to consider it a spur to urge him on to fresh work in the same path.

In presenting the balance of the proceeds of the Murchison Geological Fund to
Mr. H. Hicks, F.G.S., for transmission to Mr. Charles Lapworth, F.G.S., the
President said: —Mr. Hicks,—The Society has lately had the benefit of receiving a
most important communication from Mr. Lapworth upon the Silurian rocks of the
South of Scotland, and the Graptolites contaimed in them. This work has been the
result of many years’ successful labour; and in recognition of its merits, and with
the desire of stimulating its author to further investigation, the Council has made
this award, which I will request you to convey to him.

Mr. Hicks, in reply, expressed his high appreciation of the value of the work done
by Mr Lapworth among the Silurian rocks of Scotland, and the satisfaction that it
gave him to be selected as the medium through which an award so well merited was
to be conveyed to Mr. Lapworth, from whom he read the following letter: —

‘‘Mr. President and Gentlemen,— Permit me to express my grateful acknowledgment
of the honour you have conferred upon me by the award of the Murchison Fund. It
is, indeed, a matter of the most profound gratification to myself that what little I
have already accomplished has been regarded as meriting this valued distinction.
Were any incentive needed beyond the pleasure which ever accompanies the diligent
prosecution of original research to animate me to continued exertions in my endeavours
to aid, in some degree, in determining the perfect order of nature among the rocks
and fossils of the grandest of the geologic formations in the native country of its |
illustrious founder, it would suffice for me to recollect that the Trustees of his bounty
deem these labours worthy of substantial encouragement, and to feel assured therein
of the sympathy and approval of the Fellows of the Geological Society of London.—
Cuartes Lapwortu, 4, Kinburn Place, St. Andrews, February 12, 1878.”

The President next handed to Mr. J. W. Hulke, F.R.S., F.G.S., the Lyell Medal
and part of the Lyell Fund for transmission to George Busk, Esq., F.R.S., F.G.S.,
and addressed him as follows :—

Mr. Hulke,—The public duties of Mr. Busk prevent his receiving this token of the
Council’s appreciation of his merits as a paleontologist; and in asking you to forward
this Medal and Fund to him, I am glad to express my personal gratification in being
able to present an award, through you, to so distinguished a scientific man.

’ The Council and this Society are under great obligations to Mr. Busk, not only for
his long series of contributions to science on the fossil Polyzoa and extinct Mammalia,
but also for his having very constantly given most careful and conscientious advice
upon the value of communications. In giving this award to Mr. Busk I trust that
you will remind him that, although he has been awarded the Lyell Medal for those
researches which appear to the Council to be the most important in relation to the
science of geology, his great industry and careful method of study have enabled him
to advance our science in many subjects which refer to the antiquity of man and the
Quaternary cave- and gravel-faunas. The examination of the spoils of Brixham
cave and of the bones of the breccias of Gibraltar have been published by him, and
the results are lasting proofs of the ability of an accomplished and cautious naturalist.
Moreover, Mr. Busk, whilst studying the fossil Polyzoa, investigated the recent forms,
and his descriptions and classifications are those which are the most followed. In his
numerous researches, whether they relate to biology or to paleontology, the induc-
tive method has always been followed; and as in connexion with the study of the
fossil forms, he has constantly availed himself of the knowledge he was acquiring of
their recent representatives, the award of the Lyell Medal to him is consistent with
the wishes of its great founder.

Mr. Hulke. in reply, said that, although he regretted that circumstances had pre-
vented Mr. Busk from being present to receive personally the award of the Council,

180 - Reports and Proceedings—

it was with great pleasure that he undertook to be the means of conveying to that
gentleman this testimony of the Society’s appreciation of his paleontological labours.
Mr. Hulke also read the following letter, which had been received from Mr. Busk: —

‘32, Harley Street, Feb. 11, 1878.—Dear Mr. President,—I much regret that I
shall be unable to attend the Anniversary Meeting, and have therefore to beg that
you will be kind enough to express to the Council my very grateful sense of the
honour they purpose to do me in the award of the Lyell Medal. ‘here is none I
could esteem more highly, coming as it does from a body with which I have been
so long connected and containing so many old and valued friends, whose opinion, as
thus expressed, of the little I have been able to do in the cause of Geological Science,
has afforded me the greatest gratification. The testimonial is doubly pleasing also
from its being associated with the name of one whom, when alive, we all so much
esteemed and loved, and whose memory will be venerated in all future time. With
my best thanks to yourself and the Council, believe me, dear Mr. President, yours
sincerely, Guo. Busk.—To the President of the Geological Society.”

In handing the balance of the proceeds of the Lyell Fund to Dr. Oldham, F.R.S.,
F.G.S., for transmission to Dr. Waagen, the President said:—Dr. Oldham,—In
asking you to forward Dr. W. Waagen, of Vienna, and who was lately on the Geolo-
gical Survey of the East Indies, the Balance of the proceeds of the Lyell Fund, I
perform a very pleasing duty. Dr. Waagen’s labours in India have commended
themselves to the Council on account of their great merit and interest, and we sincerely
regret that he has suffered from the climate and from overwork. His paleontological
work has been admirable, and his great knowledge of the Ammonitide has enabled
him to arrange and identify the geological series of Cutch. His classification and his
careful analysis of species has placed him in a high rank amongst his fellow-labourers
in science; and I trust that you will be able to satisfy him that his English brethren
sympathize most thoroughly with him.

Dr. Oldham, in reply, said:—It is, Sir, to me a source of true gratification to have
been able to comply with Dr. Waagen’s request, and to receive on his behalf the
award which you ‘have just announced ; and this because, in all probability, it has
fallen to me to be more intimately acquainted with Dr. Waagen than any one here
present, inasmuch as for some years I had the happy good fortune of his co-operation-
on the Geological Survey of India, as an assistant, a colleague, and a friend. And it
will always, as it is now. be to me a pleasure to be able to bear testimony to the un-
tiring devotion, zeal, and ability which he brought to his work, and to the regret
which we all felt when continued ill-health compelled him to resign his connexion
with India. I greatly regret to say that ill-health has continued, and has, in his
native country, prevented his obtaining such employment as would bring with it
even the poor remuneration which science commands. ‘The award of the Geological
Society ot London will therefore prove to him a great solace in his depression, and a
great stimulus to his further exertion. With your permission I will read to you a
few words from Dr. Waagen’s letter to myself. He says he had received with
mingled feelings of pride and gratitude the announcement of the award. “TI do not
know how I have deserved the high honour the Geological Society of London has in
mind to confer upon me. I know only that I have always endeavoured to do my
duty as long as my strength lasted, and I hope to do my duty to science again as my
strength returns. It will be a great inducement to me to use now so much the more
my utmost zeal and endeavours to show myself worthy of the high distinction | am
to receive at the hands of the Geological Society. I wish I were able to attend
personally to express before the assembly of the Council and Members of the Geolo-
gical Society the feelings of gratitude which have been awakened through the great
kindness shown to me. A journey to London, however, at this time of the year, would
be death to me. I cannot do anything, therefore, but ask you to express, if possible,
my warmest thanks to the Society for the great honour they have deemed me worthy
to receive.”

The President then proceeded to read his Anniversary Address, in which he dwelt
in considerable detail upon the influence of advanced morphological and zoological
investigations upon our paleontological ideas and upon the geological inferences
founded upon them. The Address was prefaced by some obituary notices of Fellows
of the Society deceased during the past year, including Sir Henry James, Dr. Bryce,
Mr. John Leckenby, Dr. Bowerbank, Mr. E. Wood, and Mr. W. Harris.

The ballot for the Council and Officers was taken, and the following were duly
elected for the ensuing year :—President : H. C. Sorby, Esq., F.R.S. Vice-Prest-

Geological Society of London. 181

dents: R. Etheridge, Esq., F.R.S.; John Evans, Esq., D.C.L., F.R.S.; Prof. J.
Prestwich, M.A., F.R.S.; Prof. A. C. Ramsay, LL.D., F.R.S. Secretaries: Prof.
T. G. Bonney, M.A.; Prof. J. W. Judd, F-R.S. Foreign Secretary: Warington
W. Smyth, Esq.. M.A., F.R:S. Treasurer: J. Gwyn Jeffreys, LL.D., F.RS.
Council : H. Bauerman, Esq.; Prof. T. G. Bonney, M.A.; Prof. W. Boyd Daw-
kins, M.A., F.R.S.; Prof. P. Martin Duncan, M B., F.R.S.; R. Etheridge, Esq.,
F.R.S.; John Evans, Esq., D.C.L., F.R.S.; Henry Hicks, Esq.; W. H. Hudle-
ston, Esq., M.A.; Prof. T. McKenny Hughes, M.A.; J. W. Hulke, Esq., F.R.S. ;
J. Gwyn Jeffreys, LL.D., F.R.S.; Prof. T. Rupert Jones, F.R.S.; Prof. J. W.
Judd, F.R.S.; J. Morris, Esq.; J. A. Phillips, Esq.; Prof. J. Prestwich, M.A.,
F.R.S.; F. G. H. Price, Esq.; Prof. A. C. Ramsay, LL.D., F.R.S.; R. H. Scott,
Esq , M.A., F.R.S.; Warington W. Smyth, Esq., M.A, F.R.S.; H. C. Sorby,
le F.R.S.; Admiral T, A. B. Spratt, C.B., F.R.S.; Rev. T. Wiltshire, M.A.,
.L.S.

III.—February 20th, 1878.—Henry Clifton Sorby, Esq., F.R.S.,
President, in the Chair.—The following communications were read:

1. “ Notes on the Physical Geology of the Upper Punjab.” By A. B. Wynne,
Ksq., F.G.S.

The author stated that crystalline rocks are rare in the accession parts of the
Upper Punjab district, and that when present they consist of syenite and gneiss.
The Cambrian and Silurian formations are represented by more or less metamor-
phosed azoic slates in the Himalayan district, and in the Salt Range by a zone less
than 200 feet thick, containing either Obolus or Siphonotreta, underlain by a thick
unfossiliferous sandstone, beneath which is a deposit of gypseous marl and salt.
Above the Silurian in the Salt Range, and conformable to it, comes the Magnesian
Sandstone group and a group of unfossiliferous sandstones and clays; in the Hima-
laya these deposits are probably represented by an unfossiliferous siliceous dolomite,
which rests ungonformably upon the slates. There are no fossils indicative of rocks
of Devonian age. The Carboniferous rocks, which are also conformably deposited
on limestones, sandstones, and shales, the last sometimes carbonaceous. These
deposits contain hematite im puckets, and the oldest known Ammonites have been
found in them. An infra-Triassic group occurring in Lei Bau mountain consists of
red shales, sandstones, and red quartzitic dolomites. overlain by lighter-coloured
siliceous dolomites, which in their turn are covered by hematite, quartz breccia,
sandstones, and shales. The author believes these to have been deposited by the
same waters which subsequently laid down the Trias, which is largely composed
of limestones in the northern Himalayan area, and here and elsewhere includes
dolomites, shales, and sandstones. Numerous fossils occur in some of the beds, such
as Dicerocardium, Megalodon, and Nerinea. In the western part of the Salt Range
conglomerates composed of great blocks are regarded by the author as evidence of
proximity of land. The Jurassic deposits are local in their distribution, and consist
of shales, sandstones, and limestones, containing abundant fossils, such as Belemnites,
Ammonites, and Saurians. A dark limestone contains also Gryphee and Trigonie.
The Cretaceous deposits, when present, are conformable to the Carboniferous; they
are variable in thickness and fossil contents, and are not recognizable near Attock
between the Jurassic and Nummulitic groups. Further east a group, supposed to
be Cretaceous, includes clays with boulders of crystalline rock, which the author
regards as derived from land to the south. One of these boulders presented glacial
strie. The Eocene rocks are generally limestones, and lie conformably upon the
subjacent formations. The Nummulitic series of the Salt Range includes gypseous
and coaly shales. The salt beds sometimes attain a thickness of over 1000 feet.
The Miocene and Pliocene deposits are of immense thickness, and contain only
fossils of terrestrial and freshwater origin, so that the deposits were formed in lakes
and inland seas. The Tertiary epoch closed with the elevation of the Himalayas
and Salt Range, which was followed by a long period of change, during which
various deposits were produced, some including great quantities of erratics, which,
however, the author believes were brought to their present position rather by floating
ice than by the extension of glaciers.

2. “Description and Correlation of the Bournemouth Beds. Part I. Upper or
Marine Series.” By J. Starkie Gardner, Esq., F.G.S.

182 Reports and Proceedings—

The author stated that nothing had been written on this subject since Prof.
Prestwich’s paper, in which the beds at Hengistbury were described as of the Barton
series. No attempt had hitherto been made to correlate the beds at Alum Bay or
Whitecliff Bay with those of the mainland, and no reference was to be found any-
where to the origin and sequence of the beds between Hengistbury Head and
Bournemouth, or to their contained fossils. He had now correlated these bed for
bed with the strata at Alum Bay, and found that there is a sequence, and that the
Hlengistbury beds are higher than those of Bournemouth and do not reappear on
the coast. They are all of marine origin and were deposited by a sea advancing
from the south, as is shown by the slope of the shingle beds and the lenticular
patches of clay which mark old channels parallel to the former shore and at right
angles to the present cliff-line. They contain numerous fossils, fruits, leaves,
Mollusca, and Crustacea, the fruits resembling those of Sheppey and forming a
group of similar character. The Mollusca are of Bracklesham type, and the fossils
include three genera of Bryozoa, two of which are new to the Kocene. The
Crustacea have not yet been examined.

The author comes to the conclusion that the whole group is contemporaneous with
the Bracklesham beds, and is not of Lower Bagshot age. Similar shore-conditions
probably extended into the London basin, and the beds mapped by the Survey as
Lower Bagshot are probably of the same age as those at Boscombe, in which case
nothing more than the Bracklesham is to be met with in the London basin. The
similarity of the leaves, etc., from Bovey Tracy to those obtained by the author leads
him to infer that the former also are of Eocene, and not of Miocene age. The
author increases the thickness of the London Clay at Alum Bay at the expense of
the Bagshot beds, and diminishes that of the Bracklesham beds at Whitecliff Bay
by transferring part of them to the Lower Bagshot.

3. ‘*Notes on Certain Modes of Occurrence of Gold in Australia.” By Richard
Daintree, Esq., F.G.S.

The author stated that he had in a'previous paper (Q. J. G. S. vol. xxviii. p. 271)
proved the occurrence of gold in the Devonian rocks of Queensland, and further that
the auriferous tracts were certainly confined to those districts in which the Devonian
rocks were penetrated by certain plutonic rocks, principally pyritous diorites. These
conclusions had since been confirmed by Mr. W. C. Wilkinson and Dr. G. F. H.
Ulrich ; and the facts thus established are of the greatest practical importance to
miners. With regard to the epoch when the auriferous pyrites was deposited in the
rocks, the author expresses the opinion that most of the pyrites is contemporaneous
with the consolidation of the rocks in which it oceurs, although some may have been
subsequently introduced by infiltration; but this is not common in Australia, A
more common case is the separation of gold generally diffused through a rock into
local fissures, forming strings and veins. The author thinks that all the evidence
goes to show that the Australian auriferous veins were chiefly formed during the
earliest era of great volcanic agitation indicated by the condition of the stratified
rocks, namely the Devonian, but that they were enriched during a subsequent Tertiary
(probably Miocene) period of intense activity. No traces of auriferous veins have
yet been found in any Mesozoic or Cainozoic deposits in Australia.

4. “‘ Notes on the Geology of the Island of Mauritius and the adjacent Islets.”
Era H. T. Power, Esq., B.A. (Communicated by W. Whitaker, Esq., B.A.,

GS.

ae oti stated that the island of Mauritius consists of an elevated central
plateau, bounded by an incomplete wall of volcanic rock, round part of which there
is a coral reef and coral sand-rock, and also rocks of various colours produced by the
decomposition of volcanic rocks. Outside is a living coral reef. In the middle of
the island the old crater-wall can be distinguished, although broken; two secondary
craters are also noticed. On the north slope of the island there is a flow of columnar
basalt to the sea. There is an opening in the old coral-reef, as in the existing one
opposite the mouth of the Black River. Gabriel Island consists of a coral reef and
detrital coral rock upon a foundation of basalt, the section showing in descending
order :—1. Coral stone; 2. Conglomerate of coral, with some basalt pebbles and
shells; 3. Compact limestone, with thin layers of basalt at base. The author de-
scribed the supposed fossil trees noticed in this island by Messrs. Ayres and Clarke
(Q. J. G. S. xxiii. p. 185) as composed simply of hard portions of coral rock left
outstanding by the weathering of the softer intervening parts; they show the same

%

Geological Society of London. 183

stratification as the rock below. The islet known as Gunner’s Quoin consists of co-
lumnar basaltic lava, capping volcanic sand, below which is a browner volcanic sand
with seams of coral fragments. Flat Island is in part the remains of a volcanic
crater, and the rest consists of volcanic sand strewn with coral blocks. There are
basaltic dykes in the hill, the top of which appears to show traces of one or more
plugs. The author concludes that Mauritius was once an active volcano, now
elevated with the old reef. The islets also formed part of a volcano or volcanos,
and have also been elevated with reef-material.

IV.—March 6th, 1878.—Henry Clifton Sorby, Esq., F.R.S.,
President, in the Chair.—The following communications were read:

1. ‘On the Geology of Gibraltar.” By Prof. A. C. Ramsay, LL.D., F.R.S.,
and James Geikie, Esq., LL.D., F.R.S.

In this paper the authors, after giving some account of the physical features of
Gibraltar, described in detail the various rock-masses of which the peninsula is
composed. ‘The chief rock is a pale grey, bedded limestone, overlain by shales con-
taining beds and bands of grit, mudstone, and limestone. Fossils are very rarely
met with in the limestone, and have never as yet been found in the shales. The
only recognizable fossil they obtained from the limestone was a Rhynchonella, which
Messrs. Etheridge and Davidson think is most likely Rh. concinna. This would
make the beds of Jurassic age. The limestone forms the great eastern escarpment,
and dips west under the shales, which form the lower slopes upon which the town is
built. The dips vary from 12° or 20° up to vertical. The connexion of these strata
with the rocks of the adjoining districts in Spain and the opposite coast of Africa
was traced, and it was shown that the Gibraltar Limestone reappears in Ape’s Hill
in Barbary, while the overlying shales and the sandstones of Queen of Spain’s Chair
form all the ground to the west of Ape’s Hill up to Cape Spartel. The Jurassic
strata of Gibraltar are overlain by various superficial accumulations, the oldest of
which is a great mass of limestone-agglomerate, which is unfossiliferous, and shows
as a rule no trace of stratification. It is made up of angular blocks of limestone of
all shapes and sizes, and rests upon an uneven surface of limestone; it also covers
wide areas underneath which only shales are present. It is excessively denuded,
being worn into ravines and gullies, and presents generally a highly honeyecombed
surface. Terraces of marine erosion have also been excavated in it. It is not
now accreting, and could not have been formed under present conditions of climate
and surface. The authors gave at length their reasons for believing it to have been
the result of a severe climate. The blocks were wedged out by the action of frost,
and the heaps of angular debris thus formed were saturated by water derived from
melting snows, and so were caused to flow en masse down the mountain-slopes and
over the gently-inclined ground at their base.

The caves and fissures of Gibraltar were then described. It was shown that the
true bone-breccias were confined to these. Many of these fossiliferous breccias are
of later date than the great agglomerate, since they are met with in fissures and
caves that intersect the limestone and limestone agglomerate alike. When the
mammalia tenanted Gibraltar, Africa and Europe were united, and the climate was
genial.

All round the rock occur platforms, ledges, and plateaux, which are evidently the
work of the sea. These erosion-terraces are covered in many places with calcareous
sandstones containing recent species of Mediterranean shells. Such marine deposits
occur up to a height of 700 feet. The movement of depression was interrupted by
pauses of longer or shorter duration, and the climatic conditions were probably much
the same as at present.

After the rock had been re-elevated, the subaerial forces modified the surface of the
marine sands that covered the limestone platforms. so that they came to form long
sand slopes. The land at this period was ot greater extent than it is now, and some
grounds exist for believing Europe to have been again united to Africa, for mamma-
lian remains occur here and there in the deposits that overlie the limestone-platforms.
These relics, however, it is just possible, may be derivative. The climate was prob-
ably still genial like the present.

(eae the marine and subaerial deposits just referred to occurs an upper and
younger accumulation of massive unfossiliferous limestone agglomerate. This
deposit the authors believe to owe its origin to severe climatic conditions. After the

184 Reports and Proceedings—Geological Society of London.

marine deposits that cloak so much of the eastern side of the rock had been weathered
into subaerial sand-slopes, large blocks were detached from the cliffs and steep slopes,
and these dropped down upon the sand and were soon drifted over. By and bye the
blocks fell in such quantities that the sand-slopes in many places were completely
buried under a talus of limestone debris. This was subsequently consolidated by
infiltration into a solid agglomerate, in the same way as the underlying sands were
hardened into sandstone. These sandstones contain a few blocks of limestone only in
their upper portions. In their horizontally bedded and lower-lying portions no lime-
stone blocks occur.

This later agglomerate bears every stamp of great antiquity, and could not have
been formed under present geographical and climatic conditions. The surface is
honeycombed and worn, just like that of the solid limestone and the older limestone
agglomerate. Since its accumulation the climate has greatly changed, the present
being characterized by the absence of frost.

In concluding the authors discussed at length the cause of the cold conditions that
gave rise to the great limestone agglomerates, and argued that this cause could not
have been elevation of the land. They also pointed out that a submergence of the
Sahara would be equally incompetent to bring about the desiderated climatic con-
ditions, and that even a former much greater elevation of the land, combined with
the appearance of a Sahara sea, would fail to supply us with the severe winter climate
that was necessary to produce the great agelomerates. They thought that the most
probable explanation of the phenomena described is that the cold conditions referred
to were contemporaneous with that general refrigeration of climate which took place
over so vast an area in our hemisphere during Pleistocene times. The limestone
agglomerates they look upon as the equivalents of those glacial deposits that occur so
plentifully in our own and other countries, and the bone-breccias, which are inter-
mediate in date between the lower and upper limestone agglomerates, are paralleled
by the interglacial beds of the British Islands, Sweden, Switzerland, ete.

2. “ Notes on the Geology of Japan.” By J. G. H. Godfrey, Esq., F.G.S.

The author stated that Yesso, the most northern island of the Japanese group, had
been geologically surveyed under the direction of Mr. Lyman, but that the geology
of the other islands was chiefly known from Richthofen’s general description. He
finds that the classification of formations proposed by Lyman for Yesso holds good in
all the other islands. Thus, going from newer to older deposits, he distinguishes :—

1. New alluvium, formed by existing rivers.

2. Old alluvium, formed by ancient rivers.

3. New voleanic rocks, consisting of basalt and rhyolite. Most of the Japanese
volcanos are extinct, but a few, such as Asamoyama, are in the solfatara stage ; hot
springs abound, and earthquakes are frequent.

4. Toshibetsu group, middle or lower Tertiary sandstones, clays, and conglomer-
ates, containing lignite and petroleum.

5. Old voleanic series, rhyolitic rocks, often distinctly bedded, covering a vast
ey and with numerous lodes and deposits containing gold, silver, copper, lead, and

ende.

6. Horimui group, a coal- and lignite-bearing series of considerable extent, ap-
parently best developed in the western part of Japan, and especially in the north of
the island of Kiushiu, where the deposits are shown by fossil evidence to be of Cre-
taceous age.

7. Kamoikotan or metamorphic group, consisting of various schistose and gneissic
rocks, distinctly stratified, and usually showing a dip of upwards of 60°. Owing to
the absence of fossils the age of this group is still undecided; Riehthofen regards it
as Silurian or Devonian. Granite and diorite are frequently intruded into this
series, and they contain some important mineral veins.

The author went into considerable details upon the useful minerals of Japan,
noticing their mode of occurrence and the quantities in which they are produced.
The most important of them are:—coal and lignite, copper, silver, gold, iron, petro-
leum. lead, and tin; those of less consequence are :—sulphur (from the old craters),
antimony, mercury, kaolin, and salt.

Correspondence—Ur. A. B. Wynne. 185

CORRESPONDENCE.

WHAT IS AN ERRATIC?

Srr,—I am constrained to ask the above question in consequence
of the appearance, in the Records of the Geological Survey of India
(vol. x. p. 223), of some critical remarks by Mr. Theobald, upon my
previous reference to the “ Hrratics” of the Upper Punjab in the
same volume (p. 123).

In these remarks Mr. Theobald restricts.and applies the term
“ Hrratics” exclusively to certain blocks supposed to have been
ice-transported, advocating the idea also (vide foot-note) that the
word is only applicable in describing recent phases of geology.

Every field geologist must have observed travelled rock-fragments,
the connexion of which with glaciation was not apparent, and to
which the comprehensive term “ Erratic” would be perfectly ap-
plicable. Such transported fragments might have come from some
neighbouring mountain, or have been transported by a large river,
or drifted by a marine current, or ice might have moved them. In
all these cases I hold that the fragments would be truly erratics, no
matter at what period of geological history they wandered; also
that glacial erratics may be included in the general term.

Chalk flints are found in the shore deposits of the South of Ire-
land. They may have come from France, or the South of England,
from Antrim, or from unknown Chalk beds beneath the English
Channel, but there is no evidence that they have been transported
by ice. The materials of the Chesil Bank are accumulated by
marine currents. The agency which enclosed Wicklow granite masses
far within the Carboniferous Limestone of the County Dublin;. or
the great blocks of granite in a flow of Deccan Trap near Mund-
laisir, on the Nerbudda, in India, are unknown: but are not these
as genuinely erratics as any ice-borne blocks? If not erratics, what
else are these travelled fragments to be called ?

The erratics of the Upper Punjab are of various kinds. One
group of them dates very far back; these are all fragments of
crystalline rocks, including many of red granite from an unknown
source, and they occur imbedded in the geological series of the Salt
Range, at every stage from pre-Silurian to latest Tertiary or Recent.
Another group is of Himalayan origin; these have been transported
from the north during Tertiary, post-Tertiary, and Recent periods,
and are still travelling from the same direction: they include a great
variety of Himalayan rocks. Yet another group comprises large
angular and sub-angular blocks of Himalayan gneiss, granite, lime-
stone. etc., which are supposed to have been carried by floating-ice.
Nothing has yet been advanced to connect them with glaciation of
the immediate localities in which they are found.

Some very large angular, red granite erratics, at considerable
elevations on the Salt Range, and resting on different strata, are
probably also attributable to flotation by means of ice. The best
known of these is the Khewra Erratic.

186 Correspondence—Mr. A. B. Wynne.

Other smaller, rounded, erratic boulders of red granite, locally
numerous on or near the eastern Salt Range, but not entirely absent
to the west, are supposed by me to have been mainly released by
denudation from a Boulder-clay of probably Cretaceous age, which
only occurs in the eastern part of this range. Among these latter
boulders one has been found (not in sitit) bearing marks of glacial
smoothing and striation.

With regard to both these rounded erratic boulders and the larger
angular blocks, it is a question of interest, but of considerable
difficulty, to decide by what means they were transported. The
largest have no representatives as to size in the neighbouring Cre-
taceous (?) boulder bed, the fragments in which are usually rounded.
Mr. Theobald suggests as their source a Paleozoic boulder zone of
the range, and their derivation thence by weathering in siti; but
this is impossible, for the Paleozoic boulder beds referred to never
existed in the eastern Salt Range, or in the vicinity of these blocks !
They may therefore have been transported, as well as the northern
ones, by floating-ice.

The smaller rounded and glaciated boulder just now mentioned
would suggest Cretaceous glacial conditions with some probability,
had it been found in sité. As it occurred in a wall (though near the
boulder bed), its scoring and smoothing may have taken place either
before or after its removal from that bed, supposing that it ever was
included therein—a point incapable of proof, but open to conjecture.

At whatever period this particular boulder became glaciated, the
fact suggests that any of the similar boulders about the Salt Range
may have been originally glacial erratics: also that glacial condi-
tions may have prevailed during any period to which the deposition
of these boulders can be traced, from Paleeozoic to Recent.

Rather than admit a possibility of connexion between recent ice-
work and the occurrence of these smaller granite erratics, Mr.
Theobald prefers to assert their derivation, proximately from the
Cretaceous Boulder-clay, but more immediately from weathering of
the latest Tertiary conglomerates, because in a few instances he has
found blocks of red granite in the last-named beds. This view I
consider is untenable for two reasons, first on account of the number
of the red granite recent erratics, next because the general paral-
lelism pervading the whole of the eastern Salt Range series, from
the oldest beds upwards, involves the Cretaceous Boulder-clay
having been buried under many hundreds of feet of earlier Tertiary
strata at the time when the few granite boulders of the uppermost
Tertiary conglomerates were enclosed.'

From the whole of the facts regarding these red granite erratics,
large and small, I think the fair inference is that red granitic rocky
ground, lying probably to the south of the Salt Range, was being

1 There is some indication of a break in this Tertiary series, for apparently rolled
fragments of Nummulitic Limestone are found in it at various scattered horizons,
but the beds are all parallel. And there is no evidence that any rock of the Salt
Range older than Nummulitie was being eroded during Tertiary deposition. The

Cretaceous (?) Olive group is, however, older than the Nummulitic, and ought to
have been covered duriug deposition of any subsequent beds.

Correspondence—Mr. S. V. Wood, jun. 187

denuded and furnishing erratics, during the deposition of the whole
Salt Range series; and further, that towards the later period (if not
before) glacial conditions of the granitic region enabled masses of
this rock to be floated to the Salt Range area by the agency of ice;
there to undergo, in varying degrees, the usual operations of atmo-
spheric denudation. A. B. WYNNE.

Camp Hazara, January 1, 1878.

MR. 8. V. WOOD, Jun., IN REPLY TO DR. JAMES GEIKIE.

Srr,—Mr. James Geikie has not in his article in your last Number
put the questions in issue between us so incisively as I could have
wished.

1. I have never denied that land-ice erodes more in some places
than it does in others. What I say is that if the great basin of the
St. Lawrence has been eroded by this agency, all land surfaces must
have perished in the process.

2. I have never denied that some moraine accumulates beneath
ice. What I say is that nearly all of it travels out to the ice
termination. If it does uot, how can valleys and basins be eroded
by ice? If the bulk of what is degraded remains beneath the ice,
no basin can result; for the moraine would to the same extent
supply the place of the rocks degraded. It is only near the termi-
nation of the glacier that any considerable quantity of the moraine
accumulates beneath the ice. This (as distinguished from the first
accumulated portion of it, which resting on the middle glacial for
the most part, though not always, was formed by the dropping of
the moraine from floe-ice) I consider to have been the origin of that
later part of the chalky clay which covers Lincolnshire, Huntingdon-
shire, Cambridgeshire, and the adjoining district, accumulated in this
way when the glacier which I have described as coming southwards
over Lincolnshire terminated in the sea some twenty or thirty miles
west of the Fen boundary; as well as of that which forms the
basement clay of Holderness, which accumulated from an arm of
this glacier that came through the Humber. All this moraine, as I
hope some day to show in detail, was, except in two or three limited
spots, left beneath the sea as the ice wasted away. The part in
Holderness being followed by the depression northwards which
brought over the Shap blocks, was succeeded wninterruptedly by
another deposit of material from a different source, the purple clay ;
while the rest being in shallow water emerged before any such new
deposit could form over it.

3. Mr. Geikie speaks thus of sands escaping the action of the
overriding ice, viz.: ‘Where the gradually decreasing ice-sheet
crawled slowly to its termination, we discover considerable accumu-
lations of Till, resting upon apparently undisturbed beds of gravel,
sand, and clay”; and again he says, ‘“‘ That an ice-sheet does under
certain conditions ride over incoherent deposits of gravel, sand, silt,
clay, and peat without entirely obliterating them.”

Possibly the latter of these two statements may to some extent be

188 Correspondence—Dr. G. Linnarsson.

true, but not the former. Let us test the case by that of the North
Suffolk Cliff, which from Kessingland to Yarmouth, a distance of
fifteen miles, forms the natural section of a tract of country of similar
structure which extends inland for nearly forty miles; and over
which tract, whenever pits show the junction of the sand with the
clay, they disclose exactly the same features attending it as the cliff
does. Now this cliff, except where the valley denudation interrupts
it, is formed by a continuous deposit of undisturbed horizontally
bedded sand, containing marine mollusca and other marine organ-
isms, overlain nearly throughout by the morainic clay, often twenty,
and averaging fully twelve feet in thickness, the junction of the two
being absolutely undisturbed except in one or two places where, for
a space of a very few yards only, the clay slightly dents into and
disturbs the top of the sand, showing as it appears to. me places
where floes grounded; and the only departure from this in the
district inland is that bosses of the contorted Drift occasionally
protrude there through the sands. Now TI say that it is a physical
impossibility that the whole of this thick sheet of morainic clay,
fifteen miles wide by forty long, can have been dragged for forty
miles over the sand without either crumpling or destroying it in the
least, and without incorporating part of such sand and of the contorted
Drift bosses into itself. This impossibility becomes more striking
if we supplement the weight of this sheet of clay by the many-fold
greater weight of the ice which Mr. Geikie contends overlaid and
dragged it, “ gradually diminishing” though that ice may have been
from the prodigious thickness usually appealed to by Mr. Geikie.

I hope that in the above I have made the distinction between
our views clear; and I venture to think that Mr. Geikie, with his
numerous interglacial periods, his exaggerated ice-sheets, and his
assumption of the truth of Dr. Croll’s theory, is hardly the person
who should charge those who differ from him with “preconceived
ideas” in glacial geology. S. V. Woop, jun.

Frpruary 16, 1878.

ON THE TRILOBITES OF THE SHINETON SHALES.

Srr,—Among the fossils described in Mr. Callaway’s interesting
paper on the Upper Cambrian Rocks in South Shropshire (Quart.
Journ. Geol. Soc., vol. xxxiii. p. 652 seqq.), there are some Trilo-
bites of whose relations to forms previously known J] might venture
a few suggestions.

I do not think that Conocoryphe monile is very nearly related to
such species as C. striata. By the strongly-lobed glabella and the
dotted marginal furrow, it approaches to Angelin’s Euloma, a genus
characteristic of the Swedish Ceratopyge Limestone, which occupies
about the same position as the English Upper Tremadoc. The fauna
of the Ceratopyge Limestone is decidedly Lower Silurian, but also
the Tremadoc group—at least the Upper—has to me always seemed
to be, paleeontologically, more related to the Silurian than to the
Cambrian. The Lower Graptolite Schists immediately overlying the

Correspondence—Mr. C. Lapworth. 189

Ceratopyge Limestone are a distinct equivalent of the English
Skiddaw.

Conophrys can hardly be separated from the Shumardia of Billings
(Pal. Foss. Canada, vol. i. p. 92), which occupies a somewhat
similar, perhaps a little higher horizon. To the same genus pro-
bab!y also belongs the Battus pusillus of Sars (Isis, 1835, p. 384,
t. viil. fig. 2= Agnostus or Olenus pusillus, Kjerulf), which occurs near
Christiania together with Ceratopyge forficula.

As to Lichapyge, it cannot have any affinity to Paradowides, and
hardly to Lichas. I little doubt that it is most nearly allied to
Remopleurides, if not a true Remopleurides. In some species of
Remopleurides, as R. dorsospinifer, Portl., it is very usual to find the
pygidium united with the two hindmost thoracal segments. The
fossil described as Lichapyge would have almost the same shape, if
the terminal limb had two denticles on either side.

_ The subgenus Platypeltis seems to be more nearly related to

Niobe than to the genuine Asaphi. Also Miobe is characterized by

not having the hypostoma forked. G. Lrynarsson.
Grou. Survey Orricz, Stockuoim, March 4th, 1878.

GEOLOGICAL MAP OF SCOTLAND.

Str,—Since the publication of my review of Prof. Geikie’s Geo-
logical Map of Scotland, it has come to my knowledge that the vast
mass of new detail inserted thereupon in the areas south of the
Grampians, instead of being due to a digest of Survey work, is in truth
the result of the author’s recent personal investigations. The map
has been the constant occupation of his leisure hours for many years,
his summer holidays being generally given up to journeys for its
extension.and improvement. Hven the remarkably minute mapping
of the Old Red and Volcanic series of Fife and Forfar, the trappean
belt of the Solway, etc., noted by us for especial commendation,
was completed by himself before the Survey moved into those dis-
tricts. Though this deprives the map of anything like an official
character, it adds much to its general reliability. It is indeed highly
satisfactory to feel assured that all the new work is by the same
hand, and that consequently the details throughout are as trustworthy
as those within the areas already covered by the Survey. Looked
upon as the simple product of individual original research, the map
is amonument of rare geologic skill and energy. The author is to
be congratulated on having, single-handed, accomplished his task
with a perfection and completeness that—however widely views
may differ as to the expediency of his new systematic arrangements
—has charmed all those whose opinion is worthy of a moment’s con-
sideration. Cuas. Lapwortu.

Sr. ANDREWS, arch 20th.
DR. CARL MAYER ON THE ITALIAN TERTIARIES.

Srr,—In the last number of the “Bolletino del R. Comitato
‘Geologico d'Italia” there are again several important papers on the
Italian Tertiaries, but that of Dr. Carl Mayer calls for special atten-

190 Correspondence—Mr. A. W. Waters.

tion. Some few years ago Dr. Mayer published a paper, ‘‘ Ueber die
Nummuliten-Gebilde Ober Italiens,” in which he correlated the
Lower Tertiaries—which have in this peninsula their most import-
ant extension in the north-east, as in the Vicentine, and the present
may, to a certain extent, be looked upon as a continuation of that
communication.

This is a translation of a note on a coloured map of the north-
western parts of Italy, which was presented to the Geological Society
of France in 1877, and refers to the Miocene and Pliocene forma-
tions which occur in Central Liguria.

According to Dr. Mayer these Miocene and Pliocene beds, from
the Ligurian to the Astian, have here a thickness of 22,000 to 23,000
feet. When we consider how much more largely the last two étages
of the Tertiaries are developed in the South of Italy, we do indeed
see that the relative length of the Tertiaries has been but im-
perfectly appreciated. Nor, in considering the Cainozoic period, as
a whole, should it be forgotten that the Lowest Tertiaries are less
developed in Italy than in many places, and that, to get an idea of
the time during which Eocene formations were being deposited, we
must look to India.

Prof. Mayer is now willing to increase the calculation as to time
of some of his étages, and thinks, for instance, he can now allow us
as a minimum for the Messinian 40,000 years instead of 25,000.
This may be satisfactory as far as we think it has any signification ;
but we must say that we have but little sympathy with these
attempts to fix even a- minimum for each stage, until we are in
possession of more facts. Prof. Mayer, however, gives us his ideas
of time for each of his divisions.

These papers show the importance of Mayer’s attempts to intro-
duce a uniform nomenclature for the divisions of the Tertiaries, and
his terms, if generally introduced, would prevent us finding Italian
deposits called “Schlier,” “ Leithakalk,” ‘‘Sarmatische stufe,”’ ete.

A. W. WaTERs.

TERMINAL CURVATURE IN WEST SOMERSET, ETC.

Sir,—You would oblige by finding space for a few remarks on a
very controversial paper by Mr. Ussher, which has just appeared in
the Quart. Journ. Geol. Soc. About ten years ago I communicated
a paper to the Geological Society on what I called the Terminal
Curvature of Slaty Laminz (principally on the flat summit of
Brendon Hill, Somersetshire), and suggested a number of causes for
the consideration of geologists, none of which I confidently advocated.
So far as I can remember, all the geologists who afterwards ex-
pressed their opinion on this and other instances of terminal curva-
ture agreed with me in preferring the idea that ice in some form
had been the moving agent, with the exception of Mr. Darwin, who
stated that he had attributed somewhat similar phenomena in S.
America to earthquakes. I will not occupy your valuable space by
controverting all the objections which Mr. Ussher has brought
forward to my suggestions; but on reconsidering the subject, I

Correspondence—Mr. D. Mackintosh. 191

cannot help believing that land-ice or floating-ice would have
furnished a more uniformly-directed and horizontally-operating cause
of the curving back of slaty laminz over a large area on the flat
summit of Brendon Hill than the agency principally advocated by
Mr. Ussher, namely, “oft-repeated internal movements,” producing
curves, flexures, and contortions, and revealed at the surface by the
planing action of denuding agents. The chances against the irre-
gularly-degrading action of subaerial denuding agents having stopped
short over a large area along the horizontal plane where the summit
of the curved-back slaty laminz occurs, must have been exceedingly
small, while the presence of blocks of quartz imbedded in the more
shattered parts of the curved-back lamine (blocks which must have
been carried, or pushed forward, on perfectly level ground, to con-
siderable distances from their native veins) cannot be reconciled
with the internal movement theory. Mr. Ussher regards the “‘ Head”
as a subaerial accumulation, but Sir R. I. Murchison long ago, and
Mr. Belt and Prof. Prestwich lately, have proved that it must have
been deposited under the sea or an immense ice-water lake. It may
yet turn out to be equivalent to the Upper Boulder-clay of the
North-west of England. Neither can I agree with Mr. Ussher in
supposing that the south-western counties, any more than the north-
western, underwent a “great surface-waste and contour-moulding in
Pleistocene times.” In the north-west no fact forces itself more on
the attention than the Preglacial origin of all the leading varieties
of surface-configuration, especially the valleys. This, I believe, is
admitted by all geologists who have studied the subject.
D. Macxinrosu.

P.S.—Since the above was written, I have noticed that Mr. Ussher
regards the ‘“‘intrusion of roots acting as wedges” as the “most
common cause of strictly superficial curvature.” In all the instances
described in my paper in the Quart. Journ. Geol. Soc., for November,
1867 (excepting the one at Gupworthy), the curving back of the
slaty laminz is confined to a space only a few feet in depth. A very
little reflection must show that the intrusive action of roots could
never have persevered in one direction in bending back the inclined
lamine against their nap. With regard to the comparative absence
of curved-back laminz on the northern slope of Brendon Hill, if
the direction and high angle of the cleavage dip be there the same
as on the summit of the hill, Mr. Ussher is not right in implying
that ice moving up to the northern slope would encounter more
resistance from the nap of the laminz than on the summit, as a
simple diagram will show. D. M.

IMEIGS\ Oar by in/aNfIstOuwrse

Society or Arts Browriere Prizz.—The Council of the Society
of Arts has awarded to two Cornishmen, Messrs. Letcher of St. Day
and Camborne, the Silver Medal of the Society, and a Prize of £10,
for the best set of Blowpipe Apparatus which could be sold retail
for One Guinea.

192 Miscellaneous—T. Davies— Jadeite’ and ‘ Jade.’

Nore on ‘JaDEITE’ anpd ‘Japu.’? By Tuomas Daviss, F.G.S.

JADEITE (Damour).

Specific gravity 3:28 to 3-4; hardness 6°5 to 7. Colours milky-
white, with bright green veins and splotches, greenish-grey, bluish-
grey, clear grey and translucent as chalcedony, orange-yellow,
smoky-green passing to black, apple-green, sometimes emerald-green,
all the green tints as a rule much brighter than in the Oriental jade,
also, but rarely, of violet shades. Texture from compact, to crypto-
crystalline, and distinctly crystalline, sometimes coarsely so; fibro-
lamellar, opaque to translucent and sometimes transparent.

Thin splinters will fuse in the flame of a spirit lamp. Damour,
from analyses made by him, suggests its affinities to the epidotes.

Localities.—Central Asia, and particularly China ; also as articles
worked by the Aztecs, Mexico.

OrtENTAL JADE (Damour).’?

Specific gravity 2°96 to 3-06 ; hardness 5:5 to 6:5. Colours white
and white variously tinted, greenish-grey, many shades of green.
Texture mostly compact, rarely cryptocrystalline.

Found chiefly in Central Asia, particularly in China and on its
borders. Also in New Zealand and the Pacific Islands generally.

Specific gravity of upwards of 100 specimens from New Zealand
determined by myself have been within the limits of 3:00 to 3-02,
by far the larger number giving 3:01.

Oczrantc JapE (Damour).

Specific gravity 3°18; hardness 5:5 to 6-5. Of this variety I
possess no personal experience, the large number of objects of
jade which have come under my observation not having yielded
me one example. Damour, however, who examined four specimens,
states that in its aspect and general characters—with the exception
of its density—it much resembles the Oriental jade. It, however,
possesses a somewhat silky lustre, due to exceedingly delicate fibres
which traverse the mass. I have met with this structure frequently
however in the jade from New Zealand, which possessed the density
of 3:01. From an analysis Damour refers it to the pyroxene group,
whereas the Oriental is referable to hornblende. Vars. Tremolite or
Actinolite.

Found in New Caledonia and Marquise Island, Pacific.

None of these minerals to my knowledge have been met with in
siti; in Kurope, though the British Museum possesses a fragment of
unworked Oriental jade purporting to have been found in Turkey.

1 The above Note was communicated by my friend Mr. Davies to the translator
of ‘“‘ Keller’s Lake-Dwellings,” and appears in the Appendix to the second edition
of that work, just issued by Messrs. Longmans. Its object is to correct some inac-
curacies regarding the use of the terms ‘ Nephrite,’ ‘Jade,’ ‘Jadeite,’ ete. It
appeared to be so interesting that, with the writer’s permission, it is reprinted
here.—Enpir. Gro. Mae.

2 Damour makes the old name‘ Nephrite’ a synonym both of Oriental and Oceanic
Jade; the term Nephrite being generally abandoned by Mineralogists.—T.D.

GEOL. MAG.1878. NEW SERIES.

DECADE IL VOL.V. PLATE V.

CL. Griesbach Lith,

ttysoeumks

V West 2C° imp.

The Coast of South Devon, near Sharkham Point, looking West.
(From a Photogrash by Brinley. Totnes.)

> ae

«

DECADE IL. VOL.V.

VK AY)
IN My

a me i Wf

* Fis 3. Sketch at Woolacombe, North Devon.
\. “Morte Slates. ¥ Woolacombe. Y™~ Sand -hills (olin ) ~~ Potters Hill, ands part of Fickwell Down | right.)

.
ae St x WE.

Giza ox if Berry Head

Zee Ay eee

Gear, Me his NOES SS

v Vv Zz i, Q* ead Mudatine Bay. (contracted )
if sha Sanat
’

W West &C? lth

To illustrate M? Champernowne's paper on the Deyonidns ar Nagao! Devon.

THE

GEOLOGICAL MAGAZINE.

NEW SERIES. DECADE (VOR. Ve
No. V.—MAY, 1878.

ORIGINAL ARTICLES.

J.—Norvess on THE DEvVonIANS AND OLD Rep SanpDstTone or NortH
AND SoutH Devon.

By A. CHAMPERNOWNE, M.A., F.G.S.
(PLATES V. anv VI.)

T may seem to many geologists, accustomed to speak of the
“simple order of North Devon,” a somewhat unusual process
to fall back on the more troubled districts of the southern division
of the County for evidence upon which to take one’s stand in
interpreting the grand facts of succession within the original
“Devonian” area, Devonshire. That is, however, the plan of
campaign which I shall adopt; but instead of publishing the
paper I read last year before the British Association, in Section C, at
Plymouth (which will appear in abstract in the Annual volume of
Reports), I will only recapitulate the facts I then brought forward,
relating to the southern limestones of Torbay.

In doing so, my chief reason is that I have heard the value of
that evidence denied, and the original reading of the section strictly
adhered to.

In the two diagrams on Plate VI. Figs. 1 and 2, (1) represents the
limestone of Berry Head, and the flap of the same south of Mudstone
_ Bay; (2) the slates of Mudstone Bay; (2**) the slaty rocks of a
slightly different aspect south of the limestones; (8) red sandstones
corresponding to those of Staddon Heights and Mount Edgecumbe ;
(4) intrusive trap altering the rocks at the contact; (o’) hematite
iron-ore deposited in the hollows of the limestone, and not a bed,
as sometimes represented.

It will be observed that (1*) is a trough of the limestone beds,
the bottom of which is clearly seen; close beyond it unites with
the main mass. The right-hand tongue of trap forms the extreme
headland of Sharkham Point, the limestone adjoining it on the
right being nearly vertical, whereas it sets on at the southern end of
Mudstone Beach at an angle not greater than 45°.

Now I contend that in the minor trough which we can see, we are
furnished with a direct clue to the structure of the main mass, the
bottom of which is not seen, but is at some depth below the sea.
I believe that such dotted lines as those in diagram (1) are
natural, but that those of diagram (2) are scarcely conceivable.
The minor trough cannot be ignored, and I cannot imagine it
possible that a portion of the slates (2**) can have been introduced

DECADE II.—YOL. V.—NO. Y. 13

194 A. Champernowne—The Devonians of N. and 8. Devon.

between the two parts of limestone if they (the slates) are really
newer beds. Therefore I conclude that they are not newer beds,
but that all the rocks on the left of the diagram are older than the
limestones. This brings the Red Sandstones (3) into direct and
natural relation with those of Cockington, the Warberry, Lincombe,
etc., at Torquay, which are beneath the limestones.

I may add that thick-bedded red sandstones on the strike of
(3) in the Halwell Valley, nine miles to the westwards, dip north, the
Harbertonford limestone also dipping north, though thrown by a
N. and §S. fault on its east; and I believe that as soon as the
boundaries shall have been accurately surveyed, the real infraposition
of the red sandstones will be established beyond doubt.

Now, having at Plymouth received from my opponents, of whom
not the least formidable was my friend Mr. Pengelly, our Sectional
President, a sort of challenge to study North Devon, about a month
later I took the hint, especially as I had not visited that part of the
country since the time when I held opinions widely differing from
those I now believe to be true.

I first went to the north side of Morte Bay to see the Morte
slates close to their junction with the Pickwell Down sandstones,
and I give my notes almost as I took them.

Between Barricane Beach and Woolacombe the Morte slates dip
at 65° and 70° S., crossed by cleavage dipping north at about the
same angle; the latter dip was obviously not due to “surface
bending,” though that is sometimes seen in the neighbourhood. The
reefs are a mass of jagged edges formed by the two sets of planes.
Some very even quartz veins stand in the plane of the cleavage, and
also vertical.

The slate is here distinctly bedded. Some beds are coarse and
brownish, semi-arenaceous. One bed of brown sandstone 3 ft. 6 in.
thick, obliquely traversed by quartz veins, is just like the Ilfracombe,
etc., grits. With these exceptions, the character which the Morte
slates bear of “fine-grained, smooth, glossy slates,” will apply to
them very close to the junction.

Still nearer Woolacombe the beds bend over as they rise, evidently
forming part of a great denuded curve, as shown in the accompany-
ing sketch, Plate VI. Fig. 3. The spot is about 200 paces from the
foot of the blown sands, as near as I could take it for the advancing
tide. Still nearer the sand hills the beds dip 80° 8.

This curve, if not large enough singly, forms probably one of a
series of curves which would carry the beds right over Pickwell
Down, bringing them in again on the south.

Where the brook cuts through the sand hills at the Life-Boat
House are some very smooth slates belonging to the Morte series.
About 600 paces south of the Boat House is a reef of grey and
purplish sandstones and slates dipping 8. 65°. These should pro-
bably be included in the Old Red Sandstone; the boundary-line at
any rate must be drawn somewhere about the foot of Potter’s Hill.

The tide being almost full, I was unable to see much of the reefs
which, according to Mr. Etheridge, are very well shown; but as long

A. Champernowne—The Devonians of N. and S. Devon. 195

as there is the slightest misgiving as to the Pickwell Down beds
being intercalated between the rocks north and south of them, they
cannot, of course, help us in estimating the total thickness exposed.

In a country which has been so enormously subjected to denu-
dation, the existence of such gigantic curves. must be extremely
difficult of proof, however strong may be one’s suspicions, amount-
ing to moral certainty.

We often hear of the simplicity of North Devon. I confess I
cannot see it. Faults may be rare, and igneous rocks rarer still.
But the instances of contortions with inversion, on a small and
medium scale, are almost innumerable, and lead one to suspect the
existence of far grander ones. Any evidence of such is not to be
put aside without due examination.

Now, Mr. Etheridge states that the Morte slates cannot possibly
be the same as the Pilton, ete., slates thrown off south of the Old
Red ridge that runs into Somersetshire. He considers there is on
the north a total absence of the brown sandstones containing Cucullea
and other fossils, which form a debatable ground between the Old
Red and the true Carboniferous slates of Pilton, etc.

But even if we admit this, it is nothing more than what happens
in many other districts. In the slate country, for example, west of
the Dartington and Ogwell limestones, there is not a trace worth
mentioning of the brown and grey grits and gritty slates (with
Pleurodictyum, Chonetes, etc.), which, in Meadfoot Bay, underlie in
force the Torquay limestone.

The Baggy brown sandstones, the Meadfoot and Looe Pleuro-
dictyum beds, the Coomhola grits, and the brown grits from Combe
Martin Bay to Ilfracombe, with many others (including the Spiri-
feren-Sandstein), fall, as I believe, into one and the same general
horizon. In most of these “ Pleurodictyum” itself occurs.

The peculiarly glossy character of the Morte slates may, I think,
be accounted for by the very perfect cleavage, which is repeatedly
cutting the undulated beds at right angles. Throughout the greater
part of the Morte slates it is, as Mr. Etheridge says, most difficult to
distinguish the bedding from the cleavage: still, making every
allowance for peculiarities, I felt fully convinced that all the rocks
from Combe Martin to Woolacombe constitute but one system, and
that any division of them into Ilfracombe beds and Morte slates
must be purely artificial.

It may not be so easy at first sight to account for the absence of
calcareous matter near the southern side of the slate country which
intervenes between the two tracts of red sandstones. There are,
however, many considerations which may help to explain it, besides
the possibility of thinning out. From Combe Martin westwards the
series is excessively contorted, repeating the same beds again and
again, with the same general dip. At Broadsand, on the west side of
Combe Martin Bay, an inclined limestone V, inclosed in an off-
standing rock,’ comes into the country again at the Turnpike road

1 A photograph in Frith’s Series, No. 5901, shows this admirably. In fact much

of the details might be noted down on the Six-inch Maps, from the great number
of excellent photographs which illustrate this coast.

196 A. Champernowne—The Devonians of N. and S. Devon.

high above, only to be again doubled out; neither do I think it
makes good its descent to any depth, but is ultimately underlain to
the south."

I next studied the section on the east side of Combe Martin Bay,
and saw the Stringocephalus grits in siti. JI was struck by the
identity of the red and variegated sandstones of the Hangman with
those of the Smuggler’s Cove near Torquay, where Mr. H. B. Tawney
found Myalina (and Natica?) “in beds resembling the Hangman
sandstones.”

The Coomhola grit series succeeding is also in every respect
identical with the Pleurodictyum beds at Meadfoot. The blackish
slates, with cleavage crossing contorted brownish seams, the gritty
slates and thin grits, the massive brown grits and the fucoidal (?)
remains, are all one and the same from both bays. The boundary-
line in West Challacombe Bay is well defined. At Torquay it cor-
responds with a combe on the eastern side of the Lincombe Hill.
About the identity of these two horizons there can hardly be a doubt.

But, and I hope Mr. Etheridge will forgive me for being so
troublesome, I think the Woolacombe horizon is also the same
inverted, and that the Morte slates are the same as those we have
been considering, but deposited under deeper-sea conditions, as
indicated by the finer sediment.

The gritty series at Ilfracombe, where I was staying, is far less
than its apparent thickness, owing to the great crumpling of the
rocks, and corresponding portions on either side of a violently con-
torted trough must have been actually brought closer together in
horizontal distance than they were before any disturbance had taken
place, so that the change is less sudden than it appears.?

Then again, with the country south of Tavistock,—for miles
around Buckland Monachorum, and Horrabridge, there is not a ves-
tige of a real grit band in the Devonian slates, which, in every re-
spect. are the same as the Morte slates, but most geologists, I appre-
hend, would agree that they (the slates of Horrabridge, etc.) are not
newer than the Plymouth limestone on the one hand, or the
Petherwin beds on the other.

Supposing the Pickwell Down sandstones to be really above the
Morte slates, they, together with the fossiliferous series overlying
them, must be wholly unrepresented in South Devon, because (ex
hyp.) they cannot be any of the red beds of South Devon mentioned
at the outset, all of which can be proved older than the slates and
limestones. Every recorded instance of even apparent conformity
between the Culm Measures and Devonians, whether slate or lime-
stone, brings this conclusion nearer the verge of impossibility, the
argument becoming cumulative.*

1 T do not venture to say that there is dwt one limestone horizon, but there are
certainly not so many as there are bands on the map.

2 This is not a more striking change than that the Wenlock formation should in
one tract consist of the Denbighshire grits, inseparable from its lower portions, in
another of the Llantysilio flagstones, and thirdly of the soft calcareous shales and
limestones of Siluria.

3 JT shall not now dwell upon this aspect of the subject, viz. the relations of the
Culm Measures and Deyonians. Mr. H. B. Woodward and Mr. Reid (of H. M. Geo-

A. Champernowne—The Devonians of N. and 8. Devon. 197

I would also reason thus :—If we carry a formation, some thou-
sands of feet thick, at a high angle} to an unknown depth, we are
_bound to show that it comes up again somewhere in some form or
other, unless where a whole kingdom is masked by transgressive
rocks, it may be Mesozoic or newer rocks. So, conversely, if the
Staddon sandstones, with southerly dip, have swept over the Ply-
mouth limestone and come down from the sky, where did they
go up? The Pickwell Down sandstones go down south, under
the Culm trough, so that will not do.

But if the Staddon beds are simply rucked up, and the curve
cut away, then, in all probability, they would themselves be the
equivalents of the Pickwell Down beds; and similar reasoning would
apply to the latter in reference to the Hangman beds further north.

It makes no difference to the argument whether the group is
everywhere continuous over the mineral axis of the two counties.
But that sandstones and quartzites, whether red or no, do underlie
the killas in some districts south of the Culm Measures, the St.
Breock’s anticlinal west of Bodmin clearly shows.

As far as I have gone hitherto, the evidence is, to my mind, all in
favour of Jukes’s views, if only for “great fault” we substitute
“inverted anticlinal,” his alternative hypothesis: showing, in short,
that while the amount of disturbance is well-nigh incredible, the
original order was comparatively simple.

Again and again, formerly, have I returned home perplexed,
utterly unable to decide whether I had been working in upper or
lower slates, so contradictory was the evidence. One quarry, that
of Englebourne, where occurred in fair preservation fossils! like
those of Wissenbach, Bundenbach, ete., deep below the Hifel lime-
stone, came within a tract shaded on Dr. Holl’s map “ Upper South
Devon”!

But since I have come to regard the Devonian slates in their
entirety as one system, though most complex, with grits prevailing
in the lower part, and limestone bands in the upper; now filling
the whole space from Old Red to Coal Measures, the limestones
only nodular or absent, and anon, as these bands come in and unite
into masses of a thousand feet and upwards, dwindling away into
mere passage-beds :—since then, I say, it is marvellous how one
point after another, which before had been all obscurity, has flashed
into the broad light of day.

It is useless to think of carrying on a field survey by means
of continual appeals to the fossils: on the other hand there are,
of course, innumerable instances where beds may be thus absolutely
identified, especially where a formation (such as the Lias for in-
stance) maintains its homogeneous characters over wide areas.
This, however, the formations which intervene between the Upper

logical Survey) have laboured successfully in this field. I hope on some future
occasion myself to describe a new area of Culm shales and grits resting in perfect
conformity on Devonian limestones.

1 A selection of these are, at this moment, in the Editor’s hands for deter-
mination as far as possible.

198 A. Champernowne—The Devonians of N. and 8. Devon.

Silurian and the Coal Measures are, as a whole, singularly remark-
able for not doing.

An invaluable heritage left us by William Smith is the idea of
“strata identified by organic remains”; but yet there remain the
questions of currents, habitat and sea depth, life provinces, and so
forth: and it may be that the “Devonian” or “Wifelian” life
province of the Lower Carboniferous epoch is one of the most
remarkable and well-defined life provinces of the past. But here
we touch a whole circle of thought, to enter which would be beyond
the scope of the present sketch.

The work must still be one of time, and I agree with the
substance of Prof. Warington Smyth’s remarks at Plymouth, that
but little exhaustive work can be done before the Six-inch Maps
are in the hands of the Geological Surveyors.

Should they show the Jukesites to be wrong, and succeed in
proving that the Stringocephalus, as compared with the Productus,
limestone, is something not ‘‘sui generis” merely, but sui evi also,
no one will less regret it, save for his admiration for the master
mind of Jukes, than the writer of this paper.

Additional Note.—In speaking of the Stringocephalus Limestone as
of Lower Carboniferous age, it is fair that I should guard myself
from possible misapprehension.

Where two limestones run parallel for some distance, separated
from each other by mechanical rocks, and characterized each by its
own fossils, clearly we cannot give the same name to both, although
we may include both in the same great system.

To explain more clearly. Suppose we are tracing a band of
Posidonomya limestone among Culm Shales from west to east of
North Devon, we find that, about Westleigh and Holcomb Rogus,
changing its character, it approaches that of the Carboniferous
Limestone of the Mendips. Still, as Mr. Horace Woodward has
observed, it may represent only a part of that formation. Also, we
know from Murchison’s and Sedgwick’s writings that if we follow
the Posidonomya beds along the Westphalian frontier towards the
Rhine, at Cromford near Ratingen they put on the characters of
true Carboniferous Limestone with well-known Producti. This
upper group is accompanied at some depth below by another lime-
stone, the great Westphalian limestone, the Hifler kalk.

The strata by which the two limestones are separated are those
known as Flinz (lowest), Kramenzel-stein, and (Spirifer-) Ver-
neuili Schiefer, the whole classed as “Upper Devonian.” Murchison
(Siluria, 4th ed., p. 397) stated that, where most expanded, the
group has a thickness of 1800 feet (1000 for the “Flinz” at
Nuttlar).

Now, what parallel is there between this 1300 feet maximum,
with no Old Red Sandstone, and the vast pile of sedimentary rocks
represented by the distance from Ilfracombe to the Culm limestone
at Fremington more than 9 miles as the crow flies? A pile, of which
a part only, “the Pickwell Down sandstones,” have been estimated at
3000 feet, and parts of the series north and south of them at higher
figures still!

C. Lloyd Morgan—Geological Time. 199

The probable truth is, I submit, that the whereabouts of the
Ilfracombe limestone (= Hifler kalk) comes in again south of the
Pickwell Down sandstones, among the Pilton slates; but the Coral
polypes not having lived there, probably from deficiency of carbonate
of lime, and excess of muddy sediment, the Coral limestone is
absent, and naturally the Fauna is in the main distinct from that of
the Ilfracombe area, the only limestone of any consequence being the
Culm or Posidonomya limestone with which we set out.

Hence, by quite a different road, we arrive at the same conclusion
as before, that is to say, that the Old Red Sandstone of Pickwell
Down, ete., has been invertedly doubled up from beneath all the
rocks to which the term ‘‘ Devonian ” can be assigned.

EXPLANATION OF PLATES V. AND VI.

PLATE V.—The coast near Sharkham Point, looking west. [From a photograph by
Brinley, Totnes.]| Foreground shows crushed and folded limestone, the
lowest beds of the great mass of Berryhead and Brixham (1* in Pl. VI.)
Under these are reddish and dun-coloured slates crushed and cleaved. At the
farther point are contorted red sandstones and slates.

PLATE VI.—Diagrams, Figs. 1 and 2, show the general relations of the rocks in
Pl. V. to the coast section. Traps omitted.

Fic. 1. Supposing the limestone (1) the highest rocks of the district, the view main-
tained in the text.

Fic. 2. Supposing the limestone (1) to come between the groups (3) and (2*) above
it, and slates (2) of Mudstone Bay beneath it, according to the received
opinions of writers.

++ The part 1* slightly enlarged. (4. Volcanic.)

Fig. 3. View near Woolacombe, North Devon (described in the text).

Nore.—By tracing and retracing from my pocket-book sketch, the foreground has
somewhat lost in effect. The curve is rather under- than overdrawn.

I].—Gerotocicat Time.

By C. Luoyp Morean, F.G.S., A.R.S.M.
(Parr II.)
(Continued from p. 162.)

ar passing on to the consideration of the rate at which the various

strata were formed, it will be well, I think, to group the rocks
under six heads. First, Mechanical deposits formed in deltas,
lakes, and estuaries; secondly, Mechanical deposits along the shore-
line, in large bays, or constricted seas, such as the German Ocean ;
thirdly, Chalk; fourthly, Coral Limestone; fifthly, Coal; and
lastly, Volcanic Rocks.

I. With regard to mechanical deposits, it is obvious that they are
the products entirely, or almost entirely, of subaerial denudation,
although in the formation of the second group marine denudation
aids to some extent. Our first duty, therefore, will be to gain some
notion of the rate at which the land is wasting away under the in-
fluence of the weather, of rain, and of rivers. This subject has been
carefully studied by Mr. A. Tylor, Mr. Croll, and Professor Geikie,
and the study has been productive of most interesting results. But
a slight study of the action of rain as an agent of denudation is
necessary to make obvious the fact that the soil is gradually, and

200 — C. Lloyd Morgan—Greological Time.

continually, washed down seawards; but that as fast as soil is carried
away, fresh soil is formed by the action of rain and the weather.
Only in steep and mountainous regions is the flow of water so rapid
as to carry away the material abraded from the rocks, directly,
without any formation of soil. Now all the material washed from
the surface of the land is carried into the rivers. To ascertain,
therefore, the rate of subaerial denudation in any area, we have only
to find the amount of sediment transported by the rivers which
drain that area. If we knew, for example, the exact amount of
suspended matter which is carried into the sea by all the rivers of
England, we could readily calculate the rate at which that country
is yielding to subaerial denudation. At present, however, we have
not the requisite data for making this calculation. The matter
is much simplified if we take the cases of individual rivers, and
calculate the rate at which they are lowering the average level of the
area of country which they drain. This has been done for a few
rivers, and the following table, from Professor Geikie’s paper on this
subject, shows the number of years which it would take, at the
present rate of denudation, for each river named to remove one foot
of solid rock (the average sp. gr. of river-silt being taken at 1-9 and
that of rock at 2°5).

MGSSISSIPPI aise leyveon® Uneray e ales one foot in 6000 years.
Gan es ie Tenet aR wcee th) teem aes an <9, RDS «55
TEOATI OREO, ence pteete hice oe ees A » 1464 ,,
Rone yeh seta nee ie) | ay ees . mp GS)
Daal itt 3 ict ad ie ea ag a op » 6846 ,,
Po mane a Nahe Niet ak airs 5 9 C22) x
DS UH ECR ett BE piven Rly ce aia i » 4723 4,

Taking the mean height of the American Continent at 1496 feet,
at the present Mississippi rate of denudation that continent would
be worn away in about nine million years. Asia, at the rate at
which the Ganges destroys it, would disappear in five million years;
and if the whole of Europe were denuded at the same rate as the
basin of the Po, it would be levelled in rather less than a million
of years.

But these calculations take no account of the material removed
in solution by Chemical denudation. If this be taken into con-
sideration, the figures above quoted will have to be considerably
modified. Mr. T. Mellard Reade, in his Presidential Address to
the Liverpool Geological Society, 1877, calculated that the general
area of England and Wales was lowered by chemical denudation
at the rate of ‘0077 of a foot in a century, or one foot in 12,978
years. He also states that the matter in suspension in the waters
of the Danube are in amount three times those in solution; but
the solids in solution come down constantly; the mud is pushed
along in times of flood. Certain experiments of mine on Thames
water (taken from the river near the Waterworks, Surbiton) tend
to show, that the matter in solution, even in time of flood, was
seven times that in suspension, while in summer time this ratio
was exceeded, and was more nearly twenty times. In these ex-
periments, however, no account was taken of the solid matter

C. Lloyd Morgan—Geological Time. 201

dragged along the bottom. In the above calculations, therefore, of
the rate at which the general surface of large areas is being lowered,
we may fairly consider that the length of time mentioned as that
in which the several rivers would remove one foot of solid matter
may be reduced by, say, one-fifth, in some cases more, and in some,
perhaps, less.

Let us now see the application of these facts. The area of the
Mississippi basin is 1,147,000 square miles, that of the delta of
the same river 12,300 square miles. Let us assume that the area
over which deposit is now taking place is equal in size to the
present delta, and let us assume that only three-fourths of the
material swept off the Mississippi basin is thus deposited, the other
one-fourth being carried far into the Gulf of Mexico. Then ss'c0
of a foot is swept from the basin and deposited over, say, 12,000
square miles. This will form a deposit rather more than one-
seventh of an inch thick. One-seventh of an inch per annum may
therefore be taken to be the rate of deposit in the delta of the
Mississippi. According to the estimates of Colonel Strachey, based
on the observations of Mr. Everest, the rate of deposit is more rapid
in the delta of the Ganges and Brahmapootra, amounting to more
than one-fifth of an inch per annum, and this over an area of
65,000 square miles. The Po drains an area of about 30,000
square miles, and lowers that area +15 of a foot every year. If
we take the area of deposit at the mouth of the river at 1000 square
miles, the rate of that deposit will be nearly half an inch per
annum. To take one more case, excavations were carried on by
Mr. L. Horner, in 1850, in the great plain of Memphis, to ascertain
what thickness of Nile mud had been deposited there since the
erection of the colossal statue of Rameses II. It was found that
nine feet four inches of silt had accumulated since the foundations
of the statue had been laid some 3211 years previously. This
is at the rate of #;th of an inch per annum. Thirty-two feet below
the base of the pedestal the Nile mud was found to rest on desert
sand, and close to the line of junction a fragment of burnt brick was
discovered, which, if the rate of deposit was the same before the
erection of the statue as since its foundations were laid, was 13,496
years old. The rate of deposit at Hlephantiné, near the First
Cataract, was estimated by Sir J. G. Wilkinson at nearly double
that near Memphis, or about one-sixteenth of an inch per annum,
while the high Nile has been known to cause a deposit one inch in
depth for ten feet of water.

Taking all these facts into consideration, we shall scarcely err
in excess if we estimate the average rate of delta deposition at
one-tenth of an inch per annum. In taking the present rate of
deposition as our standard, we are not likely to err in excess: for
though in past ages the average amount of rainfall in our hemisphere
may have been at some times less than the present amount, yet at
other times, during periods of higher excentricity of the earth’s orbit,
for example, the amount was, probably, considerably greater.

With regard to estuarine and lake deposits, we have not many

202 C. Lloyd Morgan—Geological Time.

data on which to base any calculations. But I see no reason why
these formations should not accumulate as rapidly as those in a delta.
We will therefore take, hypothetically, one-tenth of an inch as the
average rate of the accumulation of all this series of deposits. _

IJ. In considering the rate of accumulation over such an area as
the North Sea, for example, we find but little on which to base any
calculations. Some of the rivers which fall into that sea, the Rhine
and Scheldt, for instance, form great alluvial flats, while the finer
and coarser materials brought down by other rivers are caught up by
the tides which sweep by their mouths, and become far more widely
scattered. The rate of deposit will be, then, in different parts of
the area, very variable. But if we take the area of country which
drains into the German Ocean at twice the size of that sea, and the
rate of subaerial denudation to be one foot in three thousand years,
we shall find that the average rate of deposit over the German Ocean
is ~4> of an inch per annum.

Along the coast-line of a great continent the rate at which sedi-
mentary deposits are formed will be still slower. A glance at a
map of North America will show from how vast an area of that
continent the Mississippi collects its waters. We have seen that
the sediment borne by those waters is collected over a comparatively
small area, in the neighbourhood of the Gulf of Mexico. Along
all the eastern coast, from Labrador to Florida Straits, but little
sedimentary deposit is being formed. If we take the strip of land
which is drained into this portion of the Atlantic to be, on the
average, two hundred and fifty miles broad, and the area over which
deposit is taking place to be a strip extending for a hundred miles
from the coast-line, and the rate of denudation to be the same as in
the Mississippi basin, we find that the rate of accumulation is 235
of an inch per annum. If again we turn to South America, we find
that almost the entire drainage of the continent is eastwards.
Taking the area which drains in this direction at about five and
a quarter million square miles, the rate of denudation the same as
in the Mississippi basin, gs's5 of a foot per annum, the eastern
coast-line at about 8500 miles in length, and the zone of deposit
to stretch one hundred miles from the shore-line, we shall find that
in this area about => of an inch of rock is deposited each year.
We must remember that much of this sedimentary matter will be
collected in the neighbourhood of the four great rivers, the Amazons,
La Plata, Orinoco, and San Francisco. Altogether, then, we may
consider that the rate of formation of mechanical deposits at a con-
siderable distance from the principal foci—as we may call the delta,
or estuarine areas—is not greater than 73,5, or perhaps, zoo of an
inch per annum.

III. Professor Huxley, in his article on ‘Coral and Coral Reefs,”
quotes the following estimate of the rate of Coral deposit from Dana’s
Manual of Geology. “The rate of growth of the common branching
Madrepore is not over one and a half inches a year. As the
branches are open, this would not be equivalent to more than half
an inch of solid coral for the whole surface covered by the Madre-

C. Lloyd Morgan—Geological Time. 203

pore; and as they arealso porous, to not over three-eighths of an
inch of solid limestone. But a coral plantation has large bare
patches without corals, and the coral sands are widely distributed by
currents, part of them to depths over one hundred feet, where there
are no living corals; not more than one-sixth of the surface of a
reef region is, in fact, covered with growing species. This reduces
the three-eighths to one-sixteenth. Shells and other organic relics
may contribute one-fourth as much as corals. At the outside the
average upward increase of the whole reef-ground per year would
not exceed one-eighth of an inch.”

IV. Professor Huxley, in his admirable lecture ‘‘On a Piece of
Chalk,” describes a specimen of Micraster in the Museum of Prac-
tical Geology, which aids us in forming some idea of the “ period
which must have elapsed between the death of the Sea-urchin, and
its burial by the Globigering. For the outward face of the valve
of a Orania, which is attached to a Sea-urchin, is itself overrun by
an incrusting Coralline, which spreads thence over more or less of
the surface of the Sea-urchin. It follows that, after the upper valve
of the Crania fell off, the surface of the attached valve must have
remained exposed long enough to allow of the growth of the whole
Coralline, since Corallines do not live embedded in mud.” “If the
decay of the soft parts of the Sea-urchin; the attachment, growth
to maturity, and subsequent decay of the Crania; and the subse-
quent attachment and growth of the Coralline, took a year (which is
a low estimate enough), the accumulation of the inch of chalk must
have taken more than a year.” Professor Huxley adds, “On any
probable estimate —the Chalk period must have had a much longer
duration than that roughly assigned to it,” on the supposition that
an inch of that rock could be formed in a year. Perhaps we may
take it as probable that a period of twenty-five years would be
sufficient for the changes to which the Micraster specimen testifies.
If so, we have no evidence that chalk may not be accumulating at the
rate of =; of an inch per annum. More than this, in the present
state of our knowledge, we cannot say.

V. With regard to Coal, Principal Dawson says that ‘“‘we may
safely assert that every foot of thickness of pure bituminous coal
implies the quiet growth and fall of at least fifty generations of
Sigillarig,” so that if we follow Professor Huxley in the moderate
supposition that “each generation of coal plants took ten years to
come to maturity—then, each foot thickness of coal represents five
hundred years,” or the material accumulated at the rate of a little
more than =; of an inch per annum. Principal Dawson’s assertion,
however, has reference to American coal, which is formed of the
accumulated stems of trees, but ‘undoubtedly the force of these
reflections is not diminished when the bituminous coal, as in Britain,
consists of accumulated spores and spore cases, rather than of stems,”
and therefore we may fairly consider that #5 of an inch is a high
estimate of the rate of accumulation of coal, and that perhaps +35
of an inch would approximate more closely to the truth.

VI. I do not remember to have seen any definite calculations

204 C. Lloyd Morgan—Geological Time.

of the rate of accumulation of volcanic rocks, nor indeed is this
to be wondered at, since the formation of volcanic products is both
local in character and spasmodic in its mode of action. It will,
however, be useful to consider a few instances of volcanic accumu-
lation, which will show that in some cases the rate of this accu-
mulation may be comparatively rapid. Sir Charles Lyell, in 1828,
measured the thickness of volcanic ash which covered the town of
Pompeii, near the amphitheatre, and found it to be ten feet three
and half inches, which gives a rate of accumulation of rather more
than one-fifteenth of an inch per annum. Over Herculaneum,
which is nearer to Vesuvius, there has accumulated a thickness
of from 70 to 112 feet of material, giving since a.p. 79 a rate of
accumulation of some two-thirds of an inch per annum. After the
eruption of Coseguina in 1835, “eight leagues to the southward
of the crater, the ashes covered the ground to a depth of three
yards and a half,” so that, if we suppose such an event to happen
once in 1800 years, the rate of accumulation of this material over
that spot would be one-tenth of an inch in a year. With regard
to lava, the well-known eruption of Skaptar Jocul in 1788 poured
forth two streams, of which one was fifty miles in length, with an
extreme breadth of some fifteen miles; while the other was forty-
five miles in length, with an extreme breadth of seven miles, the
average depth of each being one hundred feet. If such an eruption,
er minor eruptions equalling it in the amount of material emitted,
took place once in every twelve hundred years, the average rate of
deposit would be one-tenth of an inch per annum, and this without
taking into account the immense volume of ash shot forth from
Skaptar Jocul during the same eruption of 1783. Beneath the
waters of a sea, in the neighbourhood of a frequently active volcano,
a deposit of volcanic ash may form with comparative rapidity, while
the rate of growth of the volcano itself would be still greater. The
highest marine clays on the flanks of Etna are some 1258 English
feet above the level of the Mediterranean, and within them are
contemporaneous basaltic products, “‘the most ancient monuments
of volcanic action within the region of Etna.” The total height of
the mountain being 10,874 feet, we may take it that of this, 9616
feet are due to volcanic accumulations. Let us take 4500 feet as
the average height over a large area, say some 400 square miles.
Then, if the mountain began to accumulate, as Sir Charles Lyell
supposes, at the time of the Norwich Crag, and if this period may be
placed, on Mr. Croll’s estimate, some 270,000 years ago, then the
rate of the accumulation of the volcanic products of Etna must
have averaged about one-fifth of an inch per annum. In the
absence of data of any certainty therefore, we may take z'; of an
inch per annum as the rate of volcanic accumulation.

Let us, now, take the thickness of the rocks at the liberal
figure of 100,000 feet. And let us suppose that of these 50,000 ft.
were deposited at the rate of +35 of an inch per annum, and of the
remaining rocks, 25,000 were laid down at the rate of 35 of an inch
per annum, and 25,000 were formed in delta or analogous deposits

C. Lloyd Morgan—Geological Time. 205

at the rate of ='; of an inch per annum; then the time occupied in
the deposition of 100,000 feet of rock would be eighty-two and a
half millions of years. Seeing therefore that, in the first place,
100,000 feet is probably too high an estimate of the average thick-
ness of the rocks from Laurentian times to the present; that, in the
second place, those rocks should be more properly arranged in two
or three parallel series than in one long column; that, in the third
place, the rate of deposit, on which the calculation is made, is
sufficiently small; and that, lastly, on the evolution hypothesis,
there is some probability that, in old geological times, the strata
were formed more rapidly than in these latter days, is there any
reason why geologists should hesitate to accept 100,000,000 years
as the limit of geological time? Nay, for my own part I shall
not, on geological grounds, feel very uneasy if more certain physical
results than have already appeared limit the age of the rocks to fifty
millions of years.

An attempt has been made by Mr. T. Mellard Reade to estimate
the geological age of the earth by the amount of chlorides con-
tained in solution by sea-water. ‘Reckoning all the chlorides
annually brought into the sea at eight tons to the square mile, it
would take,” he says, “in even numbers, two hundred millions of
years to renew the chlorides of the sea.” How far these figures
may be correct it is not easy to say. We have at present but few
data bearing upon the subject. But supposing, with Mr. Reade,
that it would take, at the present rate, two hundred millions of years
to restore to the sea its saline constituents, then, taking into con-
sideration the exceedingly soluble nature of these chlorides, and
the high probability that in ancient geological times, when the earth
was younger, these materials were washed seawards far more rapidly
than is at present the case, it would seem a fair conclusion that from
sixty to one hundred millions of years have been amply sufficient to
render, by these means, the sea as salt as we now find it.

‘But it may be said,” writes Professor Huxley, “ that it is biology,
and not geology, which asks for so much time—that the succession
of life demands vast intervals; but this appears to me,” continues
the Professor, ‘‘to be reasoning in a circle. Biology takes her time
from Geology. The only reason we have for believing in the slow
rate of the change in living forms is the fact that they persist
through a series of deposits which, Geology informs us, have taken
a long while to make. If the geological clock is wrong, all the
naturalist will have to do is to modify his notions of the rapidity of
change accordingly.” Professor Young, also, in his Presidential
Address, British Association, Section C., speaks of Biologists “ who,
apparently unconsciously, seek to gain, by prolonging the interval
between successive groups the time which ought rather to be sought
for in tracing, were that possible, the migrations of the species
which seem to have suddenly died out.”

' The biological aspect of Geological Time is, however, in my
opinion, that which most authoritatively prevents us from accepting
the “ten or fifteen million of years” which is all Professor Tait’s

206 C. Lloyd Morgan—Geological Time.

mathematics will grant to his fellow-labourers in another branch of
Science. The evolution of plants and animals (and this is now the
only tenable hypothesis of their being) demands time for its
fulfilment. 1. In the Wealden Delta deposits we find remains of
Pterodactyles, reptiles with a highly specialized system of flying
apparatus. 2. As far back as the Triassic epoch, Mammalia,
Reptilia, and perhaps true Aves, had been evolved. 3. In Carboni-
ferous times we find that Amphibia with an elaborate dentition
(Labyrinthodonta) were in existence and continued without any
important modifications until the era of the Trias; some three or four
species of Reptiles have been found; and there are representatives
of the highly differentiated invertebrate class, Insecta. 4. In the
Upper Silurian rocks are the remains of well-developed fish, of
Echinodermata (Star-fish), and of a host of Crustacea; while the
fossils of the Lower Silurian epoch (especially the Trilobites) were
by no means of the lowliest type.

With regard to the Cambrian rocks, “after quoting Professor
Huxley’s enumeration of the many classes and orders of marine
life (identical with those still existing), whose remains characterize”
those rocks, Professor Ramsay writes: ‘‘The inference is obvious
that in this earliest known varied life we find no evidence of its
having lived near the beginning of the zoological series. In a
broad sense, compared with what must have gone before, both biolo-
gically and physically, all the phenomena connected with this old
period seem to our minds to be quite a recent description, and the
climate of seas and lands were of the very same kind as those
which the world enjoys at the present day.”

All this points to a long period of evolution, although, as Professor
Huxley truly remarks, that period is measured by the geological
clock. We must not however imagine that organic change has been
throughout all time uniform in its rate of progress. Climatal
changes—alternate periods of perpetual spring and bitter glaciation—
and geographical changes in the limits of continental and oceanic
areas—now allowing the fauna to multiply freely and expand, now
reducing stage by stage a zoological area, and causing the struggle
for life to be waged more fiercely—must have caused modification
to have at times proceeded with much greater rapidity than we now
see around us. But still the “great Phantom of geological Time”
rises before us, “ springing irrepressibly out of the facts,” to use a
metaphor of Professor Huxley’s, ‘like the Djin from the jar which
the fisherman so incautiously opened, and like the Djin again, being
vaporous, shifting and indefinable, but unmistakably gigantic.” We
may not yet be able to read the time accurately by our geological or
~ piological clock, but that clock for all that is no plaything.

There is one more aspect of this great question which remains to
be considered. We have seen that there is a theory to account for
the cold of the Glacial epoch, on the supposition that it was during
periods of great excentricity of the earth’s orbit that the glaciation
took place. If then we could ascertain at what period the excen-
tricity which produced the Glacial epoch occurred—if this hypothesis

Prof. Bonney—The Felsite of Bittadon, N. Devon. 207

be correct—we could tell the length of time which has elapsed since
that period, and should thus possess a standard to which we could
refer other geological periods.

Within the last hundred thousand years there have been two
periods of great excentricity. The former of these began 980,000
years ago, and terminated 720,000 years ago: the latter began some
250,000 years ago, and ended about 80,000 years ago. Sir Charles
Lyell at one time referred the Glacial epoch to the former period,
but subsequently agreed with Mr. Croll in assigning 250,000 years
ago as the more probable date of the commencement of the Great
Ice Age. According to this view, Mr. Croll calculates that sixty
millions of years have elapsed since the beginning of the Cambrian
period, whereas on the hypothesis that the Great Ice Age occurred
during the former period of excentricity, the beginning of the
Cambrian period will have to be placed, on the same method of
reckoning, two hundred and forty millions of years back. But
this, both the results of physical inquiry, and the known facts of
denudation, declare to be improbable or impossible, while that a
period of eighty thousand years should have elapsed since the
Glacial epoch accords well with the amount of denudation which
the Glacial deposits are found to have undergone. On this subject
Mr. Croll writes as follows: ‘Now if we assign the Glacial epoch
to that period of high excentricity beginning 980,000 years ago, and
terminating 720,000 years ago, then we must conclude that as much
as 120 feet must have been denuded off the face of the country since
the close of the Glacial epoch. But if as much as this had been
carried down by our rivers into the sea, hardly a patch of Boulder-
clay, or any trace of the Glacial epoch, should be now remaining on
the land. It is therefore evident that the Glacial epoch cannot be
assigned to that remote period, but ought to be referred to the period
terminating about 80,000 years ago. We have, in this latter case,
thirteen feet, equal to about eighteen feet of drift, as the amount
removed from the general surface of the country since the Glacial
epoch. This amount harmonizes very well with the direct evidence
of geology on this point. Had the amount of denudation since the
close of the Glacial epoch been much greater than this, the drift
deposits would not only have been far less complete, but the general
appearance and outline of the surface of all glaciated countries would
have been very different from what they really are.”

It is not without great diffidence that I have written this article.
In it I have rather aimed at giving a general résumé of a great
subject, than attempted to add anything very new. Such as it is, I
lay it before the readers of the Grotocicat Magazine.

III.—Nors on THE Feusite or Brirrapon, N. Drvon.
By Prof. T. G. Bonney, M.A., F.G.S.
cE his important paper on the Physical Structure of West Somerset
and North Devon (Quart. Journ. Geol. Soc., vol. xxiii. p. 568),
Mr. Htheridge incidentally refers to a felstone at Bittadon, saying
of it (p. 609): ‘There is no proof that the igneous rock at Bittadon

208 Prof. Bonney—The Feilsite of Bittadon, N. Devon.

is eruptive.” At the time when these words were written, it was
undoubtedly impossible, from the nature of the exposure, to decide
whether the rock was intrusive or interbedded; but, on visiting the
locality in September, 1876, I found that a small quarry (for road
metal) had been opened in the felstone, and its relations to the sedi-
mentary rocks were pretty clearly exposed.

SECTION IN STonE Pit, NEAR Brirrapon.

A, A Felsite. D Fine Slate, much crushed.
B Ibid., decomposed. E Quartz vein.
C Fine Slate. F, F Soil, Ground rising above.

The annexed diagram will, I think, render a long description
needless. The junction on the right-hand side is very clear, and the
slate a little below seems much crushed; on the left hand side
the exact line of junction is not quite so easy to trace, as the felstone
becomes much decomposed near it, but it is very nearly represented
by the dotted line. The rock on this side is a hard grey rather
lustrous slate, apparently dipping towards the 8.E., with cleavage
dipping at about 80° in the same direction, or perhaps rather more
to the south. The felstone then is evidently not interbedded, but
intrusive.

I have examined the rock microscopically ; and as its structure is
a little unusual, may complete this note by a short account of it.

Its ground-mass is compact in texture, and a dull greenish grey in
colour, rather thickly studded with small felspar crystals, commonly
from 0:1 to 0:2 inch long, of a reddish white colour; the majority
certainly being orthoclase. A few small grains of quartz are visible.
Here and there are brown ferruginous spots, apparently occupying
the place of some of the felspar, and the whole rock has a decom-
posed aspect. It is also affected slightly by cleavage. Thus, in a
hand specimen, it is not easily distinguished from a highly altered
volcanic ash, such as might be found in the Borrowdale series of
Cumberland. A slide, examined with a 1” objective, shows the
ground-mass to be rather variable; in parts it is crowded with
indistinct colourless microliths, brownish and greenish granules,
and occasional black specks; in others it is irregularly banded with
pale yellowish-green streaks. This last, on examination with both
Nicols, proves to be one of the minerals provisionally classed as
viridite; that exhibiting an irregular aggregate structure, and being
feebly double-refracting. The colourless part of the ground-mass is
now seen to be almost wholly made up of irregular rather fibrous
microliths, bright-coloured with crossed Nicols. Here and there are

George M. Dawson—Erratics at High Levels. 209

rounded patches, less transparent than the rest, and minutely granu-
lar in structure, the transparent parts of which also show bright
specks with crossed Nicols. There are many dark-brown ferruginous
stains (some rather resembling altered ilmenite), a few small quartz
grains, and numerous felspar crystals. Most of the last are ortho-
clase, rather resembling sanidine, but plagioclase is also present.
They have often ragged edges, and a broken or crushed aspect, are
sometimes almost opaque from ferruginous stains, and contain
minute ferruginous microliths. In one or two of the larger crystals
irregular groups of ill-defined microliths are included, resembling a
devitrified ¢lass,—possibly these may have once been glass enclosures,
—also rather irregular aggregates of viridite (? replacing magnesia
mica). The quartz is pretty clear, but here and there it contains a
few extremely small microliths, and perhaps cavities.

The structure of the rock, both macroscopically and microscopic-
ally, is remarkable, as it bears considerable resemblance to that of
some of the streaky ashes including broken felspar crystals from the
Borrowdale rocks of Cumberland. In the field, however, I had no
doubt of its nature, and, after many careful examinations of the
slide, I feel convinced that the resemblance is accidental. Originally,
it was probably a sanidine trachyte (there is hardly enough free
quartz for a rhyolite) with a rather variable base, imperfectly micro-
crystalline or crowded with ill-defined microliths (perhaps not very
unlike some of the Drachenfels trachyte). A slight amount of brec-
ciation may have been produced by motion just before complete
solidification, and subsequent pressure may have further crushed the
rock ; after which the original minerals have undergone considerable
alteration.

From its appearance I should imagine that this rock had solidified
at no great depth. It is intrusive in the “Grey Unfossiliferous
Slates” of HEtheridge—upper part of Middle Devonian—near their
junction with the succeeding Pickwell Down Sandstones (Upper
Devonian), and is affected by cleavage. Its intrusion must accord-
ingly be prior to the close of the Carboniferous Period, when the
cleavage was produced, and so probably happened some time to-
wards the end of the Devonian Period.

IV.—Erratics at Hic Levets 1x Nortu-Western AMERICA—
Barriers To A Great IcE-SHEET.
By George M. Dawson, F.G.S.,
Geologist to H.M. North-American Boundary Commission.

N the last edition of his Great Ice Age (1877), Mr. Geikie has

noticed at some length my descriptions of the glaciation and
superficial deposits of the central region of North America, from
Lake Superior to the Rocky Mountains; giving an outline of the
facts recorded, and of the explanation of these facts which I have
ventured to present as that which appeared to me most probable.
In one respect, however, some misapprehension seems to have

1 Quart. Journ. Geol. Soc., Nov. 1875; also Geology and Resources of the 49th
Parallel.

DECADE II.—YOL, Y.—NO, Y, 14

210 George I. Dawson—Erratics at High Levels.

arisen, probably from my omission to explain the circumstances at
sufficient length. As Mr. Geikie’s work is deservedly referred to as
an authority on the Glacial Epoch, I would here offer a few remarks
in additional explanation of the point in question.

In the vicinity of the forty-ninth parallel, boulders from the
Laurentian Axis, a great highland plateau, are distributed westward
or south-westward across the whole breadth of the Great Plains to
within twenty-five miles of the Rocky Mountains, where the country
has an elevation of about 4,200 feet. Débris from the Rocky Moun-
tains at the same time passes far eastward across the plains, the drifts
of diverse origin overlapping to the extent of several hundred miles.
The general inclination of the plain is eastward, or north-eastward,
toward the foot of the Laurentian Axis, along which Winnipeg and
associated great lakes lie, with an elevation of about 700 feet only.
The higher parts of the Laurentian Axis have an average height of
about 1600 feet.

If it be supposed that the western boulders were deposited in
their present position by glacier-ice formed on the Laurentian Axis,
or flowing over it from the north (as Mr. Geikie thinks most pro-
bable), the ice-sheet must have been pushed up-hill for a distance—
measured from the Laurentian Axis—of about 700 miles. Many
facts stated in the paper above referred to, but which cannot here
be detailed, lead me to believe that the boulders in question reached
their present position attached to sea-borne ice. Mr. Geikie, in
objecting to this hypothesis, writes :—‘‘ When we remember, how-
ever, that the maximum height of the latter (Laurentian Axis) is
only some 1600 feet, we may well ask how these boulders could
possibly have been carried by floating-ice; for, when the sea stood
at the level of 4200 feet, the Laurentian Axis, from which the
boulders have come, must have been drowned to a depth of 2,400
feet, at least!” +

This difficulty, though at first sight a very grave one, was not
ignored. I believe the evidence to be conclusive, that the western
portion at least, of the Laurentian region, was covered by a con-
fluent glacier, guided in the direction of its motion by that of the
general slope of the surface, but impelled chiefly by the pressure
resulting from the continual addition of snow and ice to its central
and higher portion. Pre-supposing this, ] have written:*? “The
occurrence of Laurentian fragments at a stage in the subsidence,
when, making every allowance for subsequent degradation, the
Laurentian Axis must have been far below water, would tend to
show that the weight and mass of the ice-cap was such as to enable
it to remain as a glacier, till submergence was very deep.” By this
it was intended to suggest that a ponderous ice-cap, several thousand
feet in thickness, continually reinforced by abundant snow-fall,
might continue to act as a glacier till the surrounding water gained
on it to such an extent as to float it bodily away. To this I might
have added as an additional, and perhaps more probable suggestion,

1 Great Ice Age, p. 472.
2 Quart. Journ. Geol. Soc., 1875, p. 622.

George M. Dawson—Erratics at High Levels. 211

that adopted by Principal Dawson to explain the transport of blocks
of sandstone from the Cumberland plains of Nova Scotia to the
summits of the Cobequid Hills, viz. that the ice-fields of successive
years may have raised these erratics and deposited them at higher
and higher levels, during a more or less rapid subsidence of the
land.1_ This process is at least competent to effect the result, and
wherever coast-ice surrounds a sinking shore, the materials of the
beach must thus be gradually warped up, though but a small pro-
portion of the material from below could ever reach a great height.

It is probably to action of this kind that Darwin wishes to appeal
in endeavouring to explain the positions of erratics in some parts of
England, though I only know his views by a reference to them by
Mr. Geikie, in a note on the same subject read by him before the
Geological Society of Glasgow in 1873, and in part reprinted in the
Great Ice Age; in which it is endeavoured to explain the facts by
the forcing up in the mass of a glacier, owing to “frontal resist-
ance” of stones included in it.

To my mind, many facts seem to show the impossibility of the
westward extension of a vast ice-sheet from the Laurentian Axis
across the plains. The most striking of these is perhaps the
existence of the great escarpment of soft Cretaceous rocks, which
runs parallel with the south-western base of the Laurentian, at an
average distance of 130 miles from it; the Winnipeg group of lakes
occupying the intervening low ground. There are gaps in this
escarpment, the most extensive being the valley of the Assineboine ;
but, in the main, it extends from near the Saskatchewan River to the
forty-ninth parallel, with a bold north-eastern front, and a height in
some places of 900 feet above the low country occupied by the lakes.
That any mass of glacier-ice should have been forced across this
escarpment without destroyig it, seems incredible; though that
the Laurentian Glacier may have reached its base in places appears
not improbable.

The wide valley occupied by the Winnipeg group of lakes and
Red River has doubtless, in the first instance, been formed by river-
erosion. A great stream at one time probably flowed southward in
it,” gradually cutting downward, and shifting its channel westward
on the sloping surface of the hard Laurentian rocks, at the expense
at first of the soft Cretaceous strata, and later of the Devonian
and Silurian limestones. The valley is pre-glacial, and, with the
escarpment, has been produced in this way precisely in the manner
explained by Professor Ramsay in describing the formation of the
Weald of Kent and Sussex.? A like process may also account, to a
great extent, for the production of the valleys now occupied by the
Great Canadian lakes, and of those of Athabasca, Great Slave, and
Great Bear Lakes in the far North-west ; all of which hold a similar
position with regard to the Laurentian region, and overlying newer
and little-disturbed rocks.

1 Acadian Geology, p. 65.

2 Geology and Resources of the 49th Parallel, p. 253.
3 Physical Geology and Geography of Great Britain.

212 Henry O. Forbes—Denudation—Rain and River.

Quite lately, Prof. E. W. Claypole, of Antioch College, Ohio,
in connexion with the theory of an all-powerful ice-sheet, has drawn
attention to the well-known great Silurian escarpment, which bears
a similar relation to the Laurentian Highlands in the Peninsula of
Ontario, and northern part of Lake Huron, and consists of a range
of cliffs in some places 200 to 300 feet high. Prof. Claypole writes:+
“Tt appears as if geologists who advocate the excavation of the
basins of the great lakes by the action of northern ice flowing off
the Laurentian Highlands are somewhat oblivious of the existence
of this escarpment. If the ice possessed the enormous eroding
power on rocks and cliffs so often attributed to it, it must certainly
have cut away and destroyed this gigantic barrier to its advance
before proceeding to scoop out deep basins to the southward.”

In discussing these points it is necessary to assume that the
relative elevation of different parts of the continent have remained
unchanged during and since the Glacial period. This is probably
not strictly true, and may be so far from correct in some cases as to
invalidate arguments based on the assumption. Unequal elevation,
great in amount, must have occurred in the west toward the close
of the Tertiary, and may have continued in progress in Glacial, or
even in post-Glacial times.

V.—Denupation—Rain AnD RIVER.
By Henry O. Forsss, Esq.

URING a recent residence in Portugal I paid a visit in Feb.
1877, to Coimbra, and while standing on the tower of the
University, whence a magnificent view of the surrounding country
can be obtained, I was much struck by the immense accumulation of
sand deposited over a wide area on both banks of the river Mondego,
by whose margin the city stands. A considerable, though, com-
paratively speaking, a small quantity was of recent date, and was
evidently brought down by the heavy rains in the months of No-
vember” and December of the previous year, which had produced
destructive floods throughout the country, and had here greatly
threatened the low-lying parts of the town. I was informed that
every year a large quantity of new sand is spread out over the
valley ; but the shortness of my stay here precluded any attempt to
estimate the yearly additions to the fluviatile stratum.
Since my return to England, however, I have fallen on some
interesting notes, geologically speaking, in various old Portuguese
works, which I send you, as they afford, I think, an approximate
estimate to the amount of denudation in a known period.

When the Alani overran the Peninsula in the fifth century, their
king Ataces captured from the Suevi the town named by the
Romans Conembrica—the spot now bears the name Condeixa a
Velha. It seems to have suffered so severely in the struggle that
the erection of an entirely new city was resolved upon on the mag-

1 Canadian Naturalist, vol. viii., No. 4, p. 197.
2 Cf. Meteorological Notes from Lisbon, Nature, vol. xvi. 1877, p. 265.

Henry O. Forbes—Denudation—Rain and River. 213

nificent site of the present Coimbra; and ere long the steep slope
was clothed with buildings down to the water’s edge. Among other
works Ataces built a bridge over the river, “ probably of one arch,
as the river was narrower and very deep.” In 1182, this structure
having perished beneath the sand, a second was ordered to be
erected over it by Count Affonso, in whose person the monarchy of
Portugal was soon after established ; and the historian further re-
lates, ‘‘that in the first years of the monarchy, during which the
Count resided in Coimbra, fleets of ships, men of war, and galleys
of great size (de grandeza Capaz) came up from the mouth as far
as the city, for the river did not then overflow its banks so much
nor bring down so much sand as now ” [1600-1650]. ‘Its waters,”
he adds too, “when kept for some time, though sharp, were not
unpleasant to the taste; but their effect on the complexion, or if
used in confections for the face, are most prejudicial, because they
spoil the skin and make it to wrinkle too soon.” This, if fact,
would lead us to suspect some chemical impurity in the water,
which was not, however, injurious to animal life, for we are further
informed that “there was good fishing in the river of chad, lam-
preys and eels.” The aguadetras, or water carriers, of the present
day, must be ignorant of its injurious properties, or disregard them,
for I saw them busily engaged in carrying it into the town for
household purposes. The sage historian attempts no explanation of
the facts he asserts, as he is “simply a recorder, and knows nothing
of medicine.” I was unaware of this peculiarity in the water at
the time, otherwise I should have obtained some for analysis. I
hope, however, to hear in a short time from my friend Dr. Paulino
d’Oliveira, Professor of Analytical Chemistry in the University, the
result of his examination, and whether there is any gold to be found
now in the sand, for ‘“anciently there was much gold taken out
close to the river; and at the top of Pena Cova, there are in many
places evident signs whence it has been been got out, and many
heaps of stones which the workers have collected.”

In 1488 Affonso V., alarmed at the ravages made by the river,
which had before this carried away many of the low-lying houses
built by Ataces, and ruined the monastery of Santa Clara on the
northern bank, prohibited under heavy penalties the clearing of the
undergrowth from the banks for a distance of a league on each side
between Cea, at the foot of the Estrella Mountains, and Coimbra.
The farmers, however, envious of the rich harvests which could be
grown there, by and bye disregarded with impunity this law, and
burned down the vegetation which checked the progress of the sand,
ploughed and cultivated the lands much to their own advantage, but
to the irrevocable devastation of the valley for their successors.

In 1518, the bridge of 1182 having almost disappeared, a third
was added to the two already swallowed up, which has in time sunk
down to give place to the goodly structure now uniting the two
banks.

At present nearly the whole plain is covered with sand from
Coimbra to the sea; while year after year recently fertile fields are

214 Prof. E. R. Lewis—Localities for Fossil Fish in the Lebanon.

being converted into sandy wastes. The depth of the river, too, is
Sam) decreasing, and can to-day float only light flat-bottomed
oats.

During the rainy season in November, I resided in Lisbon; and
took advantage of the first fair day—a fortnight after it had set
in—to visit the soft red sandstone cliffs on the south bank of the
Tagus, facing the town, and forming the south-western boundary of
the large bay into which the river expands. Here the amount of
denudation must have been thousands of tons. The whole front of
the cliffs had suffered severely, as the débris at the fort and the red
colour exhibited by the river for ten or twelve days previously
testified; but in many places quarry-like excavations had carried
the head of the cliffs back some ten to fifteen feet for a length of
several yards. A little distance inland, at a spot where the road
runs between cliffs, of the same sandstone, of 50 to 60 feet in
height, a similar effect had been produced. Here nearly a hundred
blocks of various sizes were lying. at the foot among a mass of
disintegrated sand, trees and shrubs. I give the measurement, in
métres, of, one of intermediate size, and of roughly triangular
shape: length, 2-4; thickness at base, 1:5; at apex, ‘5; average
height, 2-4. The amount of denudation for the rest of this wet
season must have been very great, when so much was accomplished
in one short fortnight.

ViI.—Tue Fossizn Fise Locanities of THE LEBANON.

By the Rev. E. R. Lewis, M.A., F.G.S.,
Professor in the Syrian Protestant College, Beiriit, Syria.

F an apology were needed for writing a few words upon the
subject of the fossil fish of the Lebanon, mine would be this,

that I have resided so near the well-known localities as to be able to
visit them often and collect more and better specimens than have
ever been found there before. Many and celebrated geologists and
paleontologists have written upon the subject of the fossil fish
found here, and yet the localities have been visited by few of those
who have written best. The distinguished paleontologist F. J.
Pictet published a volume in 1850,’ and another, together with
M. Alois Humbert, in 1866,? in which are found interesting histories
of the localities Hakel and Sahel Alma, and most excellent and
accurate descriptions and figures of the fossil fish found there up to
the last date mentioned. But for four years I have been receiving
specimens from Sahel Alma, and nearly as long from Hakel, and
now have all the specimens mentioned or described by M. Pictet
with a difference. Where he had, in many cases, imperfect speci-
mens, I have now, in all cases, superb examples; where he spoke
only by name, of species described by Costa and others, of which he

! Description de quelques Poissons Fossiles du Mont Liban, par F. J. Pictet.
Genéve, J. G. Fiek, 1850.

2 Nouvelles recherches sur les Poissons Fossiles du Mont Liban, par F. J. Pictet
et Alois Humbert. Genéve, H. Georg, 1866.

Prof. E. R. Lewis—Localities for Fossil Fishin the Lebanon. 215

had not seen examples, I have the species mentioned, which are,
in some very few cases, identical with species described by himself
under other names. But over and above all this, I have in my
collection several new and undescribed species. The possession of
so many interesting specimens has led me to study the subject with ~
care and interest, and to visit the localities from time to time, until
‘now I am induced to write a few words upon a subject of much
interest historically and geologically.

M. Pictet never visited the localities of the Lebanon in person,
and his confrére, M. Humbert, did so at a most unfavourable time,
namely, at the time of the massacres in 1860. M. Louis Lartet
did not visit the localities, at any rate he quotes Botta and Humbert
in speaking of the places; although he was himself, at one time,
within an hour of Sahel Alma, when, in 1864, he visited the Dog
River caverns.! He evidently did not know how near he was to the
fossil fish locality, or perhaps was too much interested in his
archeological investigations and discoveries. He gives, however,
valuable hints respecting the neighbouring geological formation,
and confirms M. Botta’s observations in part. Dr. Fraas did not go
so far north when he collected his valuable notes, which he has
since published.2 His book, however, has thrown much light upon
the geology of Palestine, and will be of help, indirectly, in settling
some of the questions respecting the age of the geological formations
in the Lebanon. He has visited the Lebanon more recently, and
will undoubtedly add much valuable information when he publishes
a second edition of his work. He has kindly sent me some of the
figures of new species found at Hakel, examples of which are in my
own collection also. He writes me, in acknowledgment of a few
photographs which I sent him of new species from Sahel Alma,
“But by far the most important specimens you have photo-
graphed are the Selachians, especially the Rays, which excel anything

hitherto known of this group. The remains published by Pictet
~ are poor specimens compared with your remarkably fine series.”
I shall defer writing upon the subject of the fossil fish themselves
until a future article, and content myself now with writing con-
cerning the localities, my visits to which have given me an ac-
quaintance with facts of considerable interest. But I do not think
it will be amiss to give, in English, as introductury to what I may
hereafter write, something of the history of these localities, be it
ever so briefly, before mentioning what I have discovered during
my visits to them. I am indebted, for the suggestions of various
authors, and to M. Pictet, although I have verified the references,
and corrected one or two unimportant errors into which he fell.

The first mention of the existence of fossil fish in the Lebanon is
found in Joinville’s “ Histoire de St. Louis,” edited by M. Natalis de
Wailly, page 270. During the sojourn of the King at Sidon in 1253,

1 Exploration géologique de la Mer Morte, de la Palestine et de I Idumée (p. 217),
par Louis Lartet. Paris, Arthus Bertrand, no date.

2 Aus dem Orient von Dr. Oscar Fraas. Stuttgart verlag yon Ebner und Seubert,
1867.

216 Prof. E. R. Lewis—Localities for Fossil Fish in the Lebanon.

just before his return home from the Crusades, a stone was brought
him, says Joinville, ‘‘ which was the most marvellous in the world,
for when a layer of it was lifted, there was found, between the two
pieces, the form of a fish. The fish was of stone, but lacked nothing
‘in form, eyes, bones, colour, or anything necessary to a living fish.
The king demanded a stone and found a tench within.”

Of course it is impossible to tell what species was shown the
King, and it may seem idle to hazard a guess; but the specimen was
most probably from Hikel, since that was the locality first known ;
M. Maraldi mentioning it in a letter to the “Academie des Sciences”
of Paris, in 1703, and M. C. Lebrun again in 1714, while neither
mentions Sahel Alma. Besides, the historian speaks of a stone com-
posed of layers which opened, a description applicable to most of
the specimens brought from Hikel, but rarely true of those from
Sahel Alma. In that case the specimen was most probably a Clupea,
since that is the genus found on the surface at Hakel; and it might
very easily be called a tench by a casual observer. It may seem
foolish, and of course unscientific, to deal in speculations like these,
but one seems led to it when reading of fossil fish collected 625
years ago.

M. de Blainville, so far as is known, was the first to attempt a
scientific determination of the T.ebanon fish, and he, in 1818, de-
scribed Clupea brevissima and Clupea Beurardi from Hakel.

Agassiz, in his celebrated work, 1833-48, described Clupea lata,
Clupea minima, from Hakel, and Sphyrena amici and Rhinellus -
Jurcatus from Sahel Alma. He very singularly figures the Rhinellus,
vol. ii. tab. 58>, fig. 5, and gives fig. 6 as a fragment of the same
species, when it is, in reality, a Dercetis, a genus figured in the same.
volume, tab. 66%, fig. 1 and 2, though the species may possibly be
different. The next Lebanon specimen described was by Sir Philip
Grey Egerton, Quart. Journ. Geol. Soc., 1845, vol. i. page 225, the
Cyclobatis oligodactylus from Hakel.

Then Haeckel followed in 1849, adding the genus Pycnosterina,
two species, and a new species of Clupea, the former from Sahel
Alma, and the latter from Hakel; then O. G. Costa, “ Descrizione
di aleuni Pesci fossili del Libano,” 1855, added the genera Imogaster
and Omosoma, and described a Beryx.

Finally, in 1866, appeared the valuable work of Pictet and
Humbert, above referred to, which figures and describes, or refers
to, 26 species from Sahel Alma, 21 from Hakel, and four of doubtful
origin; in all 51 species, if all be allowed, which is a matter of
doubt, since M. Pictet was in some uncertainty about the identity of
one or two species described by Costa, one described by Haeckel, and
two, at least, to which Agassiz referred only, without figuring and
describing. In these cases M. Pictet enumerates all the species
mentioned as distinct species, and describes his own examples under
different names. Examples of this will be given in another article.

M. Lartet, in the work previously cited (page 109), adds a new
Clupea to the eight or nine previously described. IJ can but think
that these species will be reduced in number when a large collection

Prof. E. R. Lewis—Localities for Fossil Fish in the Lebanon. 217

from Hikel has been systematically examined. In mentioning the
above I do not include the species known by teeth only or by single
scales. M. L. Lartet speaks of a scale found near Hasbeya in the
Anti-Lebanon, teeth of Lamna from Neby Musa (page 111); and Dr.
Fraas (Aus dem Orient, page 109) refers to teeth, etc., collected by
Dr. Roth near Jerusalem, and identifies four species. My remarks
here are confined to Lebanon localities, of which the number
hitherto known is two, Hikel and Sahel Alma, and these will be
described further on ; but during this last summer I visited a new
locality which I have never seen mentioned. It is called Hazhitla
(Djoula on the French military chart). It lies nearly south of
Hakel, and distant from it about two hours and a half over a
wretched road. The locality is in the outskirts of a most miserable
Metawali village, and the rock a friable limestone, which, in many
of the specimens, is very pulverulent, breaking into thin layers and
crumbling to pieces when the specimen is trimmed with the hammer.
At least, such is the case with most of the specimens which have
been exposed to the atmosphere a long time, as had those which I
collected. The species are the same as those found at Hakel, but
certain parts are better preserved. I obtained there several specimens
of Aspidopleurus cataphractus, Pict. et Humb., with the singular scales
of the species beautifully preserved. Iam not certain that I have
obtained any of this species at Hakel, and, since I have had several
hundreds of specimens from Hikel, including all the known species,
I have queried whether the specimen described by Pictet came from
Hakel, and was not rather brought to Hikel from Hazhtla. The
species at any rate is rare at Hakel. At Hazhila, I obtained five
examples during my short stay. Besides this species, I obtained
several specimens of Hurypholis Boissieri, Pict.; Beryx veaillifer,
Pict.; Cyclobatis oligodactylus, Egerton ; several Clupea of various
species, and two or three kinds of Crustacea. I was able to be in
the place only two hours, and was sufficiently annoyed in that time
by the clamour for “ backsheesh,”’ and the demand made by twenty
at a time to buy whatever was offered. But in the short time I was
there, and notwithstanding the unfavourable circumstances in which
I was placed while there, I obtained about fifty good specimens
picked up from road and hill-side. The exact place from which the
stone came was very near by, but I did not see and examine it, so
excited and clamorous did the ignorant fanatical people become,
threatening to break all I had collected, frightening my muleteer,
etc., etc., led on by a few who pretended that I was seeking treasures.
It required considerable tact and a great waste of Arabic to get off
with my donkey load of specimens, and as it was, I had to send the
muleteer ahead, and bring up the rear myself with a faithful atten-
dant. The locality is an interesting one, and I shall revisit it as
soon as possible.

I have said that Hakel is the oldest known locality, though it has
been rarely visited. I know of none who have visited it except M.
Humbert, and recently Dr. Fraas. The former, only, has published
anything concerning the place. It can be reached in one hard day

218 Prof. H.R. Lewis—Localities for Fossil Fish in the Lebanon.

from Beirtt. We follow the sea-coast to Jebail (the ancient Byblus),
a small seaport town between Beirtit and ‘Tripoli, then strike N.E.,
over the débris of old and ruined temples and towers which once
covered the place towards Amshit, leave it on the left, and turn
nearly east, following the windings of a ridge which looks abruptly
down upon deep valleys on either side. The road is at first covered
with fragments of limestone, abounding in cavities, and, in places,
composed almost entirely of Nerinea abbreviata, Conrad, and N. °
mamille, Fraas, all very large specimens; but soon this ceases, and
the road-passes over an almost horizontal stratum of unfossiliferous
limestone, much resembling, in general appearance, the limestone
slabs from Hakel. The travelling soon becomes slow and tedious.
The road is bounded by stone walls, which limit the fields on either
side, and the stones gathered year by year from these fields are
thrown into the road, which gradually becomes elevated above the
fields. These broken fragments, worn smooth by travel, are as
unable to give foothold as is the shingle of a beach, and the horse’s
feet sink deep at every step, making progress slow and uwun-
comfortable. In about four hard hours after leaving Jebail, Hakel
is reached. M. Botta says of it: ‘‘Ce lieu est dans une vallée profonde
située 4 une grande hauteur au-dessus de la mer car il faut monter
pendant six heures pour y arriver et les nuages la parcourent.” This
is hardly correct, though quoted by M. Alois Humbert without
comment; for, after the first ascent behind Jebail, the road keeps
a general level, sometimes rising and sometimes falling, but never
rising much higher than the points at the back of Jebail, some of
which are constantly in sight, and, finally, a considerable descent is
made just before reaching Hakel. I had no instrument with me for
determining the height accurately, but took, as a landmark, a well-
known convent near the sea, which was always in sight until Hakel
was nearly reached, and whose height is about 600 feet above the
sea. Near Hikel, with the convent and Hakel both in sight, I esti-
mated the height of the latter place at 800 or 1000 feet only, and
its distance from the sea in a straight line at about six miles. I
passed Hikel, and followed the valley nearly a mile, until the sides
of the ravine nearly closed together, and to where the valley itself
was choked by masses of fallen rock, and there, below the celebrated
fish quarries, pitched my tent, Tuesday, September 18th, 1877, and
remained there until the 28th. Circumstances were unexpectedly
favourable for me, and I collected a large and valuable lot of most
superb specimens, many of them entirely new species, and some of
them increasing very materially our knowledge of the relation of
this place to the Sahel Alma locality. I was enabled also to obtain
a more correct idea of the place, and a few most interesting facts
respecting the origin of the valley and the cause of the present
position of the strata in which the fish are found.

I have said that M. Humbert is the only one who has visited and
described the place; and his description, though brief, is correct.
Just before reaching Hakel we round a hill and descend its side
rather abruptly, until the village is reached in the bottom of a deep

Prof. E. R. Lewis—Localities for Fossil Fish in the Lebanon. 219

and narrow ravine with precipitous sides. The regular road then
crosses a little bridge, and bending west again begins to ascend the
steep hill-side opposite; but we, who are in search of the fish locality,
do not cross the bridge. We pass through the village on the right
of a little stream, een in winter is a fonreat and follow the valley
towards its head. The valley enlarges a little now, and allows of
the cultivation of a few small fig and mulberry orchards. We cross
_ the stream, and go up the valley a distance of nearly a mile, when
the sides of the valley again draw near together, and the valley
itself becomes choked by “large masses of rock which have fallen
down from the precipitous sides. On our left as we ascend, the
strata are regularly superposed, and the water has exposed a fine
section to view ; but on the right the character of the hill-side has
_ changed, and it seems a confused mass of débris. Passing through
the fallen masses which choke the valley where our tent is pitched,
we cross the stream again to the right of the valley going up, begin
to ascend diagonally, and find ourselves clambering over steeply
inclined strata. The valley becomes here a large amphitheatre,
narrowed below and above, and widening in the middle; it, at the
same time, makes an abrupt turn to the left, and assumes a direction
nearly N.H. and §.W. On the right (still going up the valley) the
strata far above our heads correspond to those on the opposite side,
but where we are standing, the strata are so much inclined that it
is difficult to walk upon them, and this inclination extends from
high up the hill-side down to the valley. The broken fragments
upon the surface begin to exhibit their contents, and weather-worn
specimens of Clupea brevissima, Blain.; Clupea Botte, Pict. et Humb. ;
with an occasional fragment of Eurypholis Boissieri, Pict., become
more and more common, until, at a distance of ten minutes’ walk
from where we left the little stream, we reach the field of operation.
All around are the evidences that collectors have preceded us. If,
now, we examine our surroundings carefully, we begin to understand
the situation. The valley is one of erosion. On the northern side
opposite us, the superposed strata show the action of water, and
reveal the different levels of the old river-bed. A hard resisting
stratum projects at various heights, with a more easily disintegrated
stratum or series of strata beneath, which have been washed away to
quite a depth in the hill-side. The same action of water has taken
place below where we are standing, and undermined the whole area,
and the fish-bearing strata have fallen down and rest where they
now are, a broken precipitous mass of débris. This fact, so far as I
know, has never been alluded to. M. Humbert speaks of the fact
of the steep inclination of the strata, and says that this inclination
has occasioned landslips, and rendered stratigraphical observation
difficult, but he does not seem to suggest that the “steep inclination ”
was occasioned by undermining and a consequent landfall. I have
not much doubt in my own mind that such is the fact.
Sahel Alma is nearer Beirtit, and may be visited from the latter
place in one day, with an allowance of two or three hours at the
locality. We leave Beirit early, pass by the traditional site of St.

220 J. T. Young—Freshwater Sponge in the Purbeck Limestone.

George’s encounter with the Dragon, canter over the sandy beach of
St. George’s Bay, and stumble on the remains of an old Roman road
which cut through a cave, leaving exposed to this day a breccia of
bone, flint flakes, etc. In specimens of this, submitted to Dr. Fraas,
he has recognized Bos priscus, superior and inferior molar, Rhinoceros
tichorhinus, inferior molar. We pass around the Dog River Pro-
montory under the celebrated stone-cut inscriptions, ford Dog River,
cross the next point, and reach Juneh Bay in an easy three hours
from Beirtit. About two-thirds the distance across the beach of this
bay we strike up the steep hill-side toward the apparently vertical
strata before us in the mountain. A short climb brings us to the
convent, under the very walls of which, and in a fig orchard,
outcrops the stratum of white chalky limestone whence so many
beautiful specimens have been obtained. The place is about 300
feet above the level of the sea, and a little more than a mile distant °
from the shore. The exposed stratum is steeply inclined, as are all
the strata in that part, and the exposed rock abounds in specimens,
which le in all directions, some of the fish passing through an inch
or more of thickness, 7.e. the head deeper in the rock than the tail,
or vice versa. The rock is soft chalky white, easily cut or sawed,
and differs entirely from the Hakel rock, which is heavy, and brittle,
with a much more distinct tendency to split into layers than the
Sahel Alma limestone.

But I have already exceeded the limits which I intended to assign
to this introductory article. The lithological and geological questions
which must be answered, the relation of the fauna of the two
principal localities, and the description of new and interesting
species, must be left to future articles.

VII.—On tHe Occurrenci oF A FRESHWATER SPONGE IN THE
Purseck Limestone.

By Joun T. Youne, F.G.S.

N the course of a re-investigation into the vexed question of the
origin and nature of Chalk flints, the very natural suggestion
occurred to me that the remains of a freshwater sponge might
probably be found in the ‘flints”’! of the Purbeck limestones, and
a recent visit to Lulworth afforded the opportunity of verifying the
conjecture. Patches of spicules with valves of Cypris, etc., etc., occur
in most of the specimens then obtained. The spicules are fusiform,
slightly curved and tuberculated like those of Spongilla fluviatilis,
but larger. The longest spicule I have been able to measure is
about s'¢ of an inch in length; largest diameter +$5 of an inch.
The spicules of S. fluviatilis from Henley-on-Thames average from
zo7 to +t5 inch in length, and are about 34> inch in diameter.
The sketch Fig. b represents a small portion of a section of “flint”
(from Stare Cove) as seen by reflected light under a 2-inch objective.
It has been touched with fluoric acid to bring out the spicules.
Before this was done, they were so obscure as to be scarcely visible,
although they are shown plainly enough on the weathered surface.
The specimen from which the section was cut is almost entirely
1 Or more properly “chert.”

\

Reviews—Prof. A. Gaudry—The Evolution of Mammalia, 221

made up of spicules. Fig. a is a spicule of S. fluviatilis as seen
under a $-inch objective. I do not wish it to be inferred that the
tuberculation of the fossil spicules is as plainly shown—it is shown,
and that is all.

I do not know that the occurrence of a fossil freshwater sponge
in the British area has been recorded before—and I thought it
might be interesting to make a note of it now. I have no doubt
a careful search would be repaid by the discovery of specimens in
which the orderly arrangement of the spicules is preserved. Should
I have an opportunity of doing so, some day I will look for them; if
not, some one else may think it worth while to do so. Meantime, as
I suppose the sponge must have a name—although I am almost
afraid to suggest one, lest it should already have been noticed and
named—I propose to call it Spongilla Purbeckensis.

REVIEwSsS.

I.—Tue Evonution oF THE TERTIARY Mammatta. Les Enchaine-
ments du Monde Animal dans les temps Géologiques Mammiféres
Tertiaires. Par Prof. Anpert Gaupry. Royal 8vo. pp. 296, avec
312 gravures dans le texte. (Paris: Libraire F. Savy, 1878.)

il lees general tendency of modern thought among scientific men
as regards the succession of animal life on the Earth has for the
last twenty years flowed in an almost uninterrupted current, not
always by the same channels, but biassed by the same inclination,
towards the prevailing doctrine of Evolution.

Indeed, whether we turn to the Hast or to the West, we are
forcibly struck by the cosmopolitan nature of scientific Opinion in
this respect. Marsh and Cope in America, Darwin, Huxley, and
Parker, in England, Gaudry in France, Haeckel in Germany, Dohrn
in Naples, are all directing our ideas in the same course. Even
Prof. Owen, whose early researches on Homologies, like those of
Linnzus in classification, were the advance-cuard of the army of
Evolutionary ideas, has of late adopted the legitimate consequences
of the Philosophy of Evolution, by tracing the descent of some
existing types of life.

These views must not, however, be classed by the reader with those
chimerical speculations in which the earlier naturalists indulged,
at the beginning of this century; more frequently they are the
genuine outcomings of laborious research, often carried on under
great difficulties, by men whose minds had been previously trained

222 Reviews—Prof. A. Gaudry—The Evolution of Mammalia.

to appreciate and understand the nature of the discoveries they
achieved.

Thus at Pikermi in Attica; in the far Western States of America ;
at Sansans, Allier, Léberon, and other localities in France, such
great and important additions have been made of late to our know-
ledge, that it has even been found possible to speak with some
confidence of the Evolution of the Mammalia since their first
appearance in numerical importance in the Cainozoic period of our
Earth’s history.

After twenty years of research among the Tertiary Mammalia,
Professor Gaudry has become convinced that the infinite diversity
of forms which they manifest are the result of one dominant plan
resulting from a Supreme Intelligence. This plan is made intelli-
gible by Evolution, which enables him to demonstrate the relation to
each other of the mammals of which remains are found in the suc-
cessive Tertiary deposits. He devotes, as a rule, a chapter to each
ordinal group, and begins with the Marsupials. In this notice we
shall follow him through the ten chapters into which the book is
divided, so as to set forth the more striking results at which the
author has arrived as the reward of researches which, in this depart-
ment of paleontology, have not been surpassed by any investigator.

There are no Herbivorous Marsupials in the Tertiary rocks; and
it is urged that, from the way in which the movements of the parent
are controlled by the helpless condition of the young, this Order
would be ata disadvantage in the struggle for existence, as compared
with the higher herbivorous mammals; and that this disadvantage
would lead to their extermination in the European Tertiary area.
In the older Tertiaries of Paris, Auvergne, and Vaucluse, Carnivo-
rous Marsupials are found which so closely resemble the existing
Opossums that at present it is not easy to separate them by generic
characters.

Hycnodon and Péerodon, though in their dentition somewhat inter-
mediate between the Placental and Implacental types, are inferred
to have been Marsupials on the evidence of the form of the axis,
which closely resembles that of the living American species Didelphis
cancrivora. This intermediate character is borne out by several
other genera, such as Palonictis, and Cynohyenodon or Proviverea
found in the Phosphorites of Quercy. Arctocyon has been shown by
Gervais to be an Omnivorous Marsupial, resembling the Bears. It
is found impossible to understand this blending of characters in the
Tertiary genera except upon the hypothesis that the Implacental
mammals of the Secondary rocks became ultimately developed into
the Placental type, and it is in this way that the anthor is disposed
to explain the many resemblances to Marsupials shown in fossil
Carnivora, living Lemurs and other animals.

The types of marine mammalia are not numerous. Squalodon in
the Miocene, and the many Cetaceans of the Antwerp Crag. This
evidence does not justify any conclusion as to the parentage of the
Cetacea. Halitherium is an intermediate type between the Dugong

Reviews—Prof. A. Gaudry—The Evolution of Mammalia. 228

and Lamantin; and Pugmeodon is intermediate between the Lamantin
and Halitherium. Zeuglodon the author is inclined to place nearer to
the Seals than the Whales, chiefly on the form of its skull.

The Pachyderms form a large group, and the resemblances of
extinct to living species are very marked. ‘The Rhinoceros was
preceded by Acerotherium, Paleotherium and Paloplotherium ; and
the distinction between these types is shown chiefly in the skull and
in the dentition. Acerotherium.is essentially a Rhinoceros without
horns, and consequently with smaller nasal bones; and the fossil
species of Rhinoceros show all intermediate conditions of this region
of the skull. The incisors of Acerotheriwm in America are three pairs,
as in Palgotheriuwm, and this number is also found in the Rhinoceros
Sivalensis of India, so that there is a passage from a complete incisive
dentition in this type, through various species of Rhinoceros to
animals in which the incisors are lost. The author deals with the
difficulty of molar teeth by accepting the view held by some
anatomists of this country, that they are really compound teeth
formed by the blending together of several simple teeth, which are
now indicated by the denticles. The Tapirs are similarly traced to
Lophiodon of the Hocene, by means of the American genus Hyrachyus ;
and the relation of the teeth of Lophiodon to those of Rhinoceros is
fully indicated. The Pigs are traced in the genus Sus to the Middle
Miocene. Sus Lockarti is nearly allied to Hyotherium, and this genus
is closely allied to Paleocherus, which resembles the Peccary of
South America. Pulgocherus passes to Cheropotamus, and this genus
is closely related to Dichobune.

The Ruminants are discussed chiefly as to their horns and teeth,
and the modifications of the extremities. Unlike the Pachyderms,
which abound chiefly in the older Tertiaries, the Ruminants
flourish most in the later periods. The earliest known genera are
Xiphodon, Dichodon, and Amphimeryx. Most of the older American
Ruminants, like Xiphodon, possess some of the characters of Pachy-
derms. In France Gelocus and Dremotherium exemplify this point.
In the Upper Miocene all the chief ruminant types are developed.
The older forms, such as Oreodon, are without horns. The first
Antelopes have the horns very small, and they appear to have de-
veloped gradually, becoming relatively large in Antelope recticornis
of the Lower Pliocene. Antlers also developed gradually, just as
they grow in complexity in the life of existing Deer. In the
Middle Miocene the genus Dicroceras has antlers with two prongs,
in the Upper Miocene the antler has three prongs, and it is only in
the Pliocene and Post-Tertiary that antlers attain the complexity
seen in existing species. Since the fossil antlers are always attached
to the skull, the author suggests that they may have been permanent
in the older types, and subsequently became deciduous, and remarks
that at first only the upper portion of the antler was shed, long
pedestals remaining attached to the frontal bones.

The earlier Ruminants, Oreodon, Dichodon, and Xiphodon, have
canines and incisors in the upper jaw like Pachyderms. An
elaborate examination of the molar teeth, however, fails to suggest

224 Reviews—Prof. A. Gaudry—The Evolution of Mammailia.

any definite generic type of Pachyderm from which the Ruminants
were evolved, though the evidence of such evolution may be re-
garded as conclusive. In the digits of the limbs, the author makes
a point of reminding us that existing genera show transitions from
types with four metapodial bones to those in which there is but one.
And by tracing the ancestral forms of the more specialized living
genera, a similar series of modifications is met with, until, in the
earlier genera, the metapodial bones are all separated. The means
by which the surviving types have been evolved are (1) the first,
second and fifth metatarsals and first cuneiform are carried back-
ward ; (2) the posterior part of the third metatarsal is enlarged to
sustain the cuneiform ; (3) the first and second cuneiform elements
of the tarsus, the second and fifth metatarsals and the trapezius
become very small; (4) the bones are modified by blending of the
various elements of the metacarpus and metatarsus.

The ancestry of the Horse occupies the fifth chapter, and is ex-
amined first by tracing the modifications of the teeth in Miocene
and Eocene genera, and afterwards by a study of the limbs in
those animals. There is but little here added to the researches
of Professor Huxley, and no departure is made from the con-
clusions of Professor Marsh. In Europe the Horse is traced from
Paloplotherium by way of Pachynolyphus to Anchitherium, which
is allied by its teeth to Palgzotherium, though its limbs approx-
imate to Paloplotherium and Hipparion, which last is little more
than a Horse with two small supplemental digits, one on each
side of the hoof which supports the limb. This latter transi-
ticn is the more interesting, since monstrosities of the living horse
sometimes appear, in which the digits on one limb are developed
exactly as in the Miocene Hipparion. Such a horse as Equus Stenonis
of the Pliocene, in which the teeth closely approximate to Hipparion,
is regarded as the immediate ancestor of the old-world Horse. In
the extremities of the limbs Acerotherium of the Middle Miocene,
which has three large digits and a small one on the outside,
diverges considerably from the type of the living horse; but
Palaotherium, which has three digits, of which the middle one is
slightly the largest, makes a nearer approximation. In Paloplo-
therium the lateral digits and metapodial bones are much more
reduced in size; while in Hipparion the reduction in size is carried a
stage further, and the middle digits proportionately enlarged. The
author quotes with approval the proposal of Professor Marsh to derive
the Horse from the Orohippus through a series of animals which pro-
gressively increased in size; but apparently without considering
that, if his own view and that of Prof. Marsh are both accepted,
then we should have two distinct lines of descent for the Horse.

The sixth chapter is an exceedingly able exposition of the grounds
of classification of the Ungulata by means of the teeth and limbs
with a view to explaining the nature of the osteological modifica-
tions which gradually evolved the Artiodactyla and Perissodactyla
from a common stock. The author considers that all the modifica-
tions which the extremities of the even and odd-hoofed Ungulata

Reviews—Prof. A. Gaudry—The Evolution of Mammalia. 225

present result from the necessity that the foot should evenly sup-
port the pressure of the body. In the latter the external digit is
rather more slender than the internal digit, and from this fact an
explanation is derived for the circumstance that in the Perissodac-
tyla the fibula rests directly on the tibia instead of articulating with —
the caleaneum, as in the Artiodactyla. This leads to the articulation
of the calcaneum with the cuboid becoming smaller, and therefore to
the attenuation of the fourth digit, so that the whole weight of the
animal is thrown on the astragalus, which is carried by the navicu-
lare, which is itself carried by the third cuneiform bone, which sup-
ports the third or middle digit of the foot. Hence it follows that the
astragalus of the odd-hoofed types, which is flattened in front, is
modified from the type of the even-hoofed animals, and the same
conclusion is supported by a consideration of the other tarsal bones.
It is even less difficult to establish a common parentage for the two
groups by means of the teeth. These considerations raise the ques-
tion whether the basis of classification should be taken from the
divergent descendants which survive or have been elaborated, or
whether the geological evidence has not now rendered it imperative
to unite in one great group orders of animals which have hitherto
been regarded as having a wider separation from each other than has
here been set forth.

The seventh chapter deals with the Elephants, Mastodon and
Dinotherium, all of which date from Miocene times. But slender
additions are made to current knowledge of these animals, and
while indicating the obvious similitudes of their teeth to those of
some living types, the author finds no paleontological grounds for
suggesting their parentage.

Similar difficulties, arising from the imperfect way in which
their remains are known, beset the comparative study of Eden-
tates, Rodents, Insectivora and Cheiroptera, to which the next
chapter is devoted. Hdentates are known in Europe, in the
Eocene and Miocene; and in America they are only known from
the newest formations. Macrotherium, an enormous animal from the
Middle Miocene, might have been a climber. It had relatively small
hind-limbs, and claws drawn back towards the metacarpals, so as not
to impede progression on the ground. Ancylotheriwm from Pikermi
is intermediate between the climbing and walking Hdentates. A
few Rodents occur in the Eocene; in the Upper Miocene of Greece
we have Porcupines; Hares in the Pliocene of Auvergne; and
Beavers in the Upper Miocene ; all the extinct genera only differ
from those now living in minor characters. Hedgehogs, Shrews,
and. Moles, are all represented in geological time ; Hedgehogs in
the Miocene of Auvergne; Moles in the same locality, as well as
at the foot of the Pyrenees and on the Rhine; Shrews are found in
the Bourbonnais ; some of the old Miocene forms are so much
generalized that Plesiosorex, for instance, was regarded as a Hedge-
hog by De Blainville. The Cheiroptera are very imperfectly known,
and give no evidence of their descent.

The ninth chapter treats of the Carnivora. Here, especially, it is

DECADE II.—YOL. Y.—NO. V. 16

226 Reviews—Prof. A. Gaudry—The Evolution of Mammalia.

to be noted that while all the common living types have representa-
tive species in a fossil state, many date to the Pliocene period. And
many of the extinct genera serve to bridge over the interval be-
tween surviving animals. Thus the Miocene genus Amphicyon, with
a number of the most striking characteristics of Dogs, yet was a
plantigrade animal like the Bears, probably able to climb, and
resembled bears in minor dental characters. Again, Hyenarctos
is between the Bears and Amphicyon, having an inner row of denticles
to the teeth. In the same way Cynodon from the Phosphorites of
Quercy completely bridges over the gap in dentition between the Civets
and the Dogs. Hyzenas, in the same manner, are shown to have been
closely related to the Civets by means of the fossil genera Ictitherium
and Hyenictis; the former is a modified Civet with four digits like
Hyeena, and producing similar coprolites; while the latter is a
modified Hyzena, closely approaching Ictitherium. The Martens are
represented in Miocene times by European and American genera,
but these do not make such striking approximations to the Civets as
to altogether break down the distinction between the two groups.
Some remarkable fossil genera, like Macherodus, have left no descen-
dants. The author inclines to believe that carnivorous animals may
perhaps be descended from the Herbivora, pointing out that Bears
most nearly resemble the Pachyderms.

The last chapter deals with Lemurs and Apes. The oldest lemur
is Cenopithecus from the Kocene, and from Quercy there are several
lemurs which show affinities with the Ungulata, suggesting a com-
mon origin for lemurs and several of the Hocene pachyderms. This
is also strongly indicated by the fact that Cuvier arranged the
lemurine genus Adapis with the Pachyderms, and that Gervais
provisionally classed the Lemur Aphelotherium near to Pachyderms.

Some of the earlier Apes also appear to have affinities with Pachy-
derms ; this is seen in Cebocherus from the lignites of Débruge ; and
the conclusion that Hyracotherium presents some ape-like characters
is supported by the fact that our illustrious anatomist, Prof. Owen,
described, from the London Clay, some teeth as those of a monkey
which he was afterwards led to refer to that genus. The teeth of
Oreopithecus, from the Miocene of Italy, show some resemblances to
Cheropotamus. 'True apes, and anthropomorphous apes, date from
the Middle Miocene. The apes include Semnopithecus from the
Sewalik Hills and Montpellier, and Mesopithecus from Pikermi,
which appears to have been gregarious, and to have been a walker
rather than a climber. This latter genus is intermediate between
Semnopithecus and the Macaques. The anthropomorphous apes in-
clude Pliopithecus and Dryopithecus, the latter being of a very high
type, but differed from Man in many points, especially in the large
size of the canines in the males. Finally, a number of observers
have recorded from the Miocene bones which show cuts such as
might have been made by Man, and although the believers in these
supposed evidences of the antiquity of our race are few, the evi-
dence is supported by the occurrence of flint knives and other flint
weapons in the Middle Miocene of Beauce. But the interval is so
great between these beds and the post-glacial gravels, and the

Reviews—Keller’s Lake-Duwellings. 220

character of the human work is so like that from the more recent
deposits, that some further evidence may be desired before this
remote antiquity for Man is generally accepted.

In conclusion the author gives a summary, pointing out the brief
duration in time of all the giant types, and gives an impartial
analysis of the conclusions which we have condensed in the pre-
ceding pages. He considers that from the doctrine of Evolution we
should be justified in regarding a deposit as Kocene if the mammals
were numerous, but unlike those now living and unassociated with
true Ruminants, Solipeds, Proboscidians and Apes. In the older
Miocene we should expect to find living genera rare, Marsupials
disappearing, Pachyderms passing into Horses, and the incoming of
true Ruminants. In the newer Miocene Marsupials would be lost,
but Ruminants, Horses, Whales, Edentates, Elephants, Carnivora, and
Apes, are represented by numerous individuals and many genera,
some of which diverge from living forms. While in the Pliocene
the genera are mostly still living, though the species are extinct.

No popular exposition of paleontological results, so clear and pro-
found, and intelligible to all who have a slight acquaintance with
Natural History, has ever before been offered to scientific students.
And the 300 excellent woodcuts carry conviction home better than
words could do, and make the work invaluable for easy reference to the
chief forms of fossil mammals. Points of difference with an author
presenting so many striking and suggestive ideas must almost inevi-
tably occur to readers; and for ourselves we may say that the reasons
given are not altogether convincing that the even-hoofed Ungulata
were the parents of the odd-hoofed section of the group, because
the argument, to have been conclusive, should have been carried
from the digits up to the fibula, and not from the fibula to the
digits. And we venture to suggest that no cause competent to
modify the relations of the fibula could be found elsewhere than in
the influence of digital development and modification upon the tarsus.
But although such like arguments may sometimes need a little
more elaboration, no one can rise from the perusal of the book
without being conscious that an invaluable survey of the Mammalia
has been made by a great master of the subject, or without a feeling
of gratitude to its distinguished author. H. G. Seerery.

JI.—Tue Laxe-Dweiines oF SWITZERLAND AND OTHER Parts oF
Europs. By Dr. Ferprnanp Ketier. Translated and arranged
by Jonn Epwarp Les, F.S.A., F.G.S. Second edition, greatly
enlarged. In two volumes. Royal 8vo. vol. i. pp. xvi. and
696, with a frontispiece and 50 woodcuts; vol. ii. pp. 28 and
206 lithographic plates. (London: Longmans, Green, & Co.,
1878.)

WING to the great impetus given of late years to all branches
of Prehistoric investigations, the publications on this subject
have become so numerous that one almost needs to take advice in
order to ascertain what to read, think, or avoid, on all Quaternary
matters. We may, however, without hesitation, recommend to our
readers such undoubtedly standard works as Prof. W. Boyd-

228 Reviews—Keller’s Lake-Dwellings.

Dawkins’ “Cave Hunting”; Dr. John Evans’ “ Ancient Stone Im-
plements of Great Britain”; Messrs. Lartet and Christy’s “ Reliquiz
Aquitanice” ; Sir John Lubbock’s “ Prehistoric Times” ; Sir Charles
Lyell’s ‘‘ Antiquity of Man”; Mr. HE. B. Tylor’s “ Harly History of
Mankind”; Mr. Edward T. Stevens’ “ Flint Chips”; and lastly,
but by no means least, Keller’s “‘Lake-Dwellings of Switzerland
and other Parts of Europe.”

In August, 1877, we drew attention to this work, then in the
press! The first appearance of Keller’s book in English was
noticed by us in the GeoLocicaL MaGazine for 1866 (Vol. III.
p- 460). This edition formed a single volume of 426 pages and
96 plates. We now find it has grown, in 1878, to 740 pages and
206 plates, containing representations of more than two thousand
five hundred objects.

Dr. Keller may congratulate himself on his good fortune in
possessing such a friend and translator as Mr. John Edward Lee to
make his researches known to so large a body of readers as the
English language is sure to command, both here and in the
Colonies, and also in the United States.

Mr. Lee’s original edition of Keller’s work mainly consists of a
translation of his six reports presented at various times to the
Antiquarian Association of Zurich, with notes and some few addi-
tions. More than ten years have elapsed since that publication
appeared. In the new edition we have embodied the whole of
the previous matter and a seventh report by the same excellent
authority. To this Mr. Lee has added a short account of every
settlement of interest which has been carefully explored, always,
as far as possible, translated or abstracted from the original report
or memoir. In the first edition about 1500 lake-dwellings were
noticed; the present edition contains descriptions of between two
and three thousand !

It is hardly too much to say that the work, as it now appears,
embodies all that has hitherto been written upon this interesting
subject, whether from English, French, Swiss, German, Austro-
Hungarian, or Italian sources of information. Strange to say, that
the Dutch, who, from the earliest times to the present day, have
always been the greatest pile-dwelling and pile-driving nation in
the world, find no place in these volumes. Will no enterprising
native venture to write a history of the first pile-dwelling in
Holland? Or is the Dutch mind too prosaic and matter-of-fact to
enter upon such speculations? We hope, if Mr. Lee ventures on a
third edition, he will avail himseif of this suggestion.

One feature of the new edition of Keller’s ‘“ Lake-Dwellings ”
is the introduction of much valuable information relative to the -
persistence among various races of mankind of the practice of
erecting similar structures at the present day. If the old feudal
stronghold of our ancestors, with its outworks, drawbridges, and
moats, is but a modification of the still more primitive crannoge
and pfahlbau: what wonder then if actual pile-dwellings should have

1 See Grou. Mac. 1877, Dec. II. Vol. IY. p. 366.

Reviews—Keller’s Lake-Dwellings. 229

survived among modern savages in their original simplicity in such
varied localities as the Lake-district of Central Africa; New
Guinea; Venezuela; on the Gulf of Maracaibo; on the Orinoco ;
and the Amazons in South America? In Singapore and Japan
this form of pile-dwelling over the water is still in vogue. It is the
best possible proof that in the construction of these primitive habi-
tations, as in the fabrication of his weapons, early man, under
similar circumstances, and impelled by like necessities, has always
acted in a similar manner independent of time and space. We do
not therefore attach any special importance to the fact of the early
Swiss Lake-Dwellers using this form of habitation; we believe it
was a necessity of their existence which caused them so to build.
Dr. Keller himself observes :—‘‘ As no national distinction can be
proved between the dwellers on land and the dwellers on the lakes,
so in like manner no serious doubt can arise as to the identity of the
people who first made use of stone celts, then made implements of
bronze of admirable quality, and, lastly, forged its weapons and
tools out of iron. The difference of material used for the various
implements marks the epochs which follow each other in the de-
velopment of one and the same race, not the degree of civilization
of different peoples.” (p. 493.)

The researches of Professors Heer, Rutimeyer, and others, into the
plant- and animal-remains discovered on the sites of these amphibian
habitations show that even the older pile-dwellers attempted the cul-
tivation of some cereals to be stored together with dried fruits for
winter use; and although in the earliest dwellings the larger
proportion of animal-remains are made up of the bones of wild
beasts, such as the red deer, the wild boar, roebuck, etc., yet they
seem at that period already to have possessed the cow and the goat.
At first these were no doubt kept simply for the sake of their milk ;
but oxen were employed from a very early period to draw loads; the
discovery of the pig as a source of excellent food, and probably as
a substitute for cannibal repasts, belongs also to an advanced period
of primitive life. From the earliest times man appears to have
been accompanied by the dog, which, in his hunter state, and also
afterwards as a shepherd or swineherd, would prove a most valuable
companion, worthy to share in his repasts and to enjoy the warmth
and shelter of his hut or cave.

The process of Evolution can clearly be traced in the relics of
these early abodes of man; for with advancing civilization we find
not only the diminution of wild animals eaten as food, and the
obvious greater consumption of domesticated breeds of pig, ox and
sheep, but his weapons increase in quality of workmanship and
materials, and the horse, and probably also the ass, were added to
his other domesticated animals.

One interesting geological feature connected with these early
habitations in Switzerland is, that in many instances they afford
valuable evidence as to the rate of the filling up of lakes by vegetable
growths, and by the accumulation of sediments or alluvial deposits.
From the evidence collected by Mr. Lee it would seem that of the

230 Reviews—The Geology of the Fenland.

two causes in operation, plant-growth is a more rapid agent in
filling up lakes than the washing down of sediments. Or perhaps
it would be more correct to say that every deep mountain lake
is being slowly but surely shallowed by the yearly accumulation
of sediments, and that having at last reached a moderate depth,
at which aquatic plants thrive and grow most freely, the final filling
up of the lake is accomplished in a comparatively brief period of
time by the more rapid production of peat, and the fixing of iron.

Mr. Lee alludes (in a foot-note, on p. 495) to Mr. A. Tylor’s
“pluvial period,” which he thinks “‘many of the lake-dwelling
facts, as far as they go, seem rather to favour;” but we are not dis-
posed attach any special or peculiar meteorological import to the
growth of peat save that it proves the climate to have been humid,
the temperature probably equivalent to that of Ireland, the country
no doubt being everywhere clothed with forests which even spread
high up the mountain sides.

If we venture to make any generai remark on this new edition of
Keller’s Lake-Dwellings, it is in reference to the scrupulous fidelity
of the translator (whether in dealing with the Reports of Dr. Keller
himself, or, the thousand and one separate papers by other authors,
which he has so laboriously brought together in this volume) in
always adhering to the original text, when a departure from it would,
we think, have been not unfrequently an improvement, and have in
many instances avoided a too-frequent recurrence, in different words,
of the same general ideas, which, having been once enunciated,
need not be again reiterated. Whether as the faithful historian or
the patient translator, we would crave none better than Dr. Keller
and Mr. John Edward Lee.

IIJ.—Memorrs or THE GroLocicaL Survey or ENGLAND AND WALEs.
THe GEOLOGY oF THE FeNLAND. By Sypney B. J. SkuRTcuHLy,
F.G.S. 8vo. pp. 885, with a map and 23 plates. (London.)

HERE is no tract in the British Isles which could be expected
to offer less temptation to the geologist than that large area,
including the Bedford Level, which is known as the Fenland.
Forming portions of six counties,’ it occupies about 1300 square
miles, for the most part consisting of a monotonous plain from five
to twenty feet above the mean tide-level, and only diversified by
slight elevations which, like islands, stand out here and there from
the apparently dead-level of the fens. Much of this land, we are
told, is below the high-water mark of ordinary tides, and would be
overflowed almost daily, but for the erection of great banks along
the sea-board.

Happily the geologist is not confined to the scenes of the present
day, for however uninviting these may be, he can usually excite
within himself some enthusiasm by directing his mental vision to
those changes which have taken place in past times, in restoring to
his mind’s eye pictures of the ancient scenery, and in reading those

1 Lincoln, Northampton, Huntingdon, Cambridge, Suffolk, and Norfolk.

Reviews—The Geology of the Fenland. 231

lessons in the history of life which the hard facts of Geology con-
tinually reveal. Thus such a dreary district as the Fenland may
become invested with considerable interest.

To attain to this happy state of mind, much hard work must first
of all inevitably be done; and Mr. Skertchly, in prosecuting the
work of the Geological Survey, has devoted four years to field-work
and to the study of the ancient and modern historical records which
treat of the land he describes.

It must not be supposed that the district has altogether been
neglected by geologists, and attention is drawn to the observations
especially of Sedgwick, Rose, Fisher, Bonney, and Seeley, who have
made frequent excursions into the Fenland.

Their general conclusions, however, by no means harmonize with
those at which Mr. Skertchly has arrived, and if they seem to be
rather severely criticized, some of them, at any rate, will be able to
do battle in support of their views.

Briefly to state his conclusions, we may use Mr. Skertchly’s own
words. He claims to have finally settled the relations of the peat
and silt beds to each other, the age and marine nature of most of the
gravels, the origin of the Boulder-clay, and the interglacial age of
the paleeolithic deposits.

Mr. Skertchly describes the Fenland as an old bay excavated in
the Kimmeridge and Oxford Clays, and filled up with peat, and
gravel, and silt, and Boulder-clay.

He states that the estuaries of the fen rivers are now enclosed
marshes; and the Wash, whatever parts of its area may formerly
have been, holds no such relation to the rivers, nor are any of the
fen-beds delta-deposits.

Three areas of gravel are noted at the surface: a northern area
which merges into the hill drift of Lincolnshire; a western area
which is a true beach gravel; and a southern and eastern area, which
seems to be the remains of the old valley gravels of the adjacent
rivers. These are all older than the peat and silt beds, and are
considered newer than the Chalky Boulder-clay.

The peat land occupies the western and southern portions of the
Fenland; the silt land the north and central portions; and they
show that the ground was a debatable one between the land and sea:
for when the one prevailed, peat grew; and when the other had the
mastery, silts were deposited. There is no definite order of suc-
cession in these two groups, inasmuch as they inosculate one into
the other. .

In the vicinity of the highlands buried forests are found in the
peat, and five distinct horizons of trees are noticed.

In the valley gravels, which are known to be newer than the
Chalky Boulder-clay, paleolithic implements are found; and in the
newer fen strata many neolithic implements are met with.

The author discusses the break between them, and maintains that
the palzolithic deposits belong to an interglacial period.

We need not follow him through his history of the Fenland in
Roman, Early English, and subsequent times. He has gone over

232 Reviews—The Geology of the Fenland.

all the old records of the district and epitomized them; a study
which is most important for the proper understanding of the present
state of the Fenland. Notices of the chief drainage works, descriptions
of the physical features, and accounts of floods and storms are given.

The questions of evaporation and drainage are discussed in some
detail, and the author draws attention to and describes an instru-
ment designed by Mr. 8. H. Miller, F.R.A.S., and himself, called
the Evaporimeter; the object of which is to ascertain the effects of
different soils upon evaporation.

Full accounts of other meteorological matters, such as rainfall,
winds, ete., are given. These and other details render the work as
much a manual of the Archeology and Physical Geography of the
Fenland, as of its Geology.

One chapter of especial interest to geologists is that on the Boulder-
clay. This deposit skirts the Fenland, and in Mr. Skertchly’s opinion
underlies most of that area, and is in some places surprisingly thick.

Thus the well sunk in 1828, at Boston, pierced beds to a depth
of 572 feet, the whole of which he states to be Quaternary ; and of
these the Boulder-clay is estimated to have a thickness of 460 feet.
The shells which are mentioned at various depths belong to the
genera Gryphea and Ammonites, specimens of which have been
preserved. These, he states, are all glaciated.

This is the Chalky Boulder-clay, and Mr. Skertchly argues that it
is of terrestrial origin. He points out, in support of this view, that
its included materials vary according to the nature of the deposit over
which it is spread. At the same time Chalk is almost invariably
present. If it were iceberg drift, the component materials must be
those of the distant gathering grounds, and not those of the rocks
they fall upon as the berg melts away. Moreover, for icebergs to
carry the débris, we must admit a submergence of at least 500 feet,
and granting this, then very little Chalk would be left above water,
and no traces at all of the Oxford and Kimmeridge Clays, the wrecks
of which are locally abundant in the Boulder-clay.

There is an account of the great boulder of Cretaceous rocks at
Roslyn Hole, Ely, which formerly led to much discussion in the
pages of this Macazinz, and Mr. Skertchly states that he has seen
Boulder-clay underlying these transported beds.

A classification of all the beds in the Fenland, with remarks on the
physical conditions which attended their deposit, is given, and the
author points out that he independently came to similar conclusions
concerning the Glacial and Post-Glacial events, to those arrived at
by Dr. James Geikie, and published in “The Great Ice Age.” He
briefly adverts to his discovery of paleolithic implements in inter-
glacial brick-earth beneath the chalky Boulder-clay near Brandon, a
further account of which is promised in a Memoir on the Gunflint
Factory. Until all the details of such an interesting discovery are
made known, we must be content to suspend our judgment. Never-
theless, however startling it may seem, and however much opposed
to our early teachings and convictions, so much new light has been
thrown on the physical and paleontological history of the Glacial

Reports and Proceedings—Geological Society of London. 233

Epoch by the writings of Dr. James Geikie and Dr. Croll, that our
faith in the entirely Post-Glacial age of man requires considerable
modification, and we are forced to admit that he dwelt in this
country at any rate before some of the great epochs of cold which
glaciated our northern counties.

Enough has been said to indicate that this volume treating of the
Geology of the Fenland contains matter of more than local interest.
It is well illustrated. and we can only regret that its price (forty
shillings) must have a very disadvantageous influence upon its
distribution.

[P.S.—Sinee writing the notice of Mr. Skertchly’s book on the
Fenland, I have had the opportunity of again visiting Brandon under
his guidance, and have seen evidence which completely satisfies me
that some of the beds yielding paleeolithic implements are older than
the Chalky Boulder-clay. I hope Mr. Skertchly will soon make
public all the evidence upon which his interesting and most im-
portant discovery is founded.—H.B.W.]

ISHII CASVayS) JNAN aD) Jessi QD Camas sca NnSrS)-

<<

Gronocioat Society or Lonpon.—I.— March 20, 1878.—Henry
Clifton Sorby, Esq., F.R.S., President, in the Chair.

The following communications were read :—

1. “On the Chronological Value of the Triassic Strata of the
South-western Counties.” By W. A. HE. Ussher, Hsq., F.G.S.

The author maintained that the general thinning-out of the Trias
in the South-Devon and West-Somerset area as it is traced north-
ward, of which he adduced evidence, proves that this area was not
connected with that of Gloucestershire and the midland counties
until the later stages of the Keuper; and endeavoured to show by a
comparison of sections that the area east of Taunton and south of
the Mendips was not submerged before the deposition of the Lower
Keuper Sandstone, and probably not until the later stages of its
formation, the Quantocks acting as a barrier dividing the Bridge-
water area from the Watchet valley. He thought that a subsidence
progressing from south to north led to earlier deposition in South
Devon, and to a consequent attenuation of the lower beds towards
Watchet and Porlock. Hence the lowermost beds of the Trias of
the south coast are much thicker than their more northerly equi-
valents, and probably were still thicker where the English Channel
now flows, some beds perhaps dating as far back as Permian times.
The presence of numerous fragments of igneous rocks (quartz-
porphyries) in the basement-beds of the South Devon Trias, and
the absence of known corresponding rocks in the county, led the
author to infer that the cliffs and beds of the early Triassic sea were
composed of such rocks, any undestroyed portions of which would
probably occur either under the Triassic beds near Dartmoor and
between Newton and Seaton, or in the area now occupied by the
English Channel. As continuity is evident only in the upper

234 Reports and Proceedings—

division of the Trias, between the area of Devon and Somerset and
that of the midland counties, and there is no unconformity in the
former, the author maintained that the upper marls, upper sand-
stones, and probably the conglomerate and pebble-bed subdivision
of Devon and Somerset, are equivalent in time to the Keuper series
of the Midland counties, and that deposition took place in Devon
and Somerset between Keuper and Bunter times, bridging over the
hiatus marked by unconformity in the Midland counties.

2. “Note on an Os articulare, presumably that of Iguanodon
Mantel.” By J. W. Hulke, Esq., F.R.S., F.G.S.

In this paper the author described what he believed to be the Os
articulare of Iguanodon Mantelli, from the best specimen of a series
of five collected by the Rev. W. Fox, of Brixton, in the Isle of
Wight. He remarked that the mandible represented by this bone
differs greatly from that of the Crocodilia, and, in a less degree, from
that of extant Lizards, while in some respects it resembles that of
Hypsilophodon Foxii. From this resemblance and the relative
abundance of the bone in the same beds which have yielded
mandibular rami of Iguanodon, he felt justified in referring the bone
to the latter Saurian.

3. ‘Description of a new Fish from the Lower Chalk of Dover.”
By E. Tulley Newton, Hsq., F.G.S.

The author referred to his previous descriptions of fishes from
British Cretaceous rocks belonging to Prof. Cope’s genera Portheus
and Ichthyodectes, and stated that he had since obtained a form
referable to the allied genus Daptinus. The specimen is in the
collection of the British Museum, and was procured from the Grey
Chalk of Dover by Mr. Gardner. It consists of the head and some
vertebree, the characters of which are described in detail by the
author, who stated that in some characters, especially the degree of
flattening of the teeth, the fish seems to stand between Ichthyodectes
and Daptinus, and hence proposed to name it Daptinus intermedius.
The author further noticed the existence in the British Museum of
a right maxillary bone from the Lower Chalk of Dover, which he
thinks may indicate a second species of the same genus.

4, «Further Remarks on adherent Carboniferous Productid.”
By R. Etheridge, jun., Esq., F.G.S.

The author stated that since his former paper on this subject
(Q.J.G.S. vol. xxxii. p. 454), his Productus complectens had been
found in various localities, as in Northumberland, in Fifeshire, and
near Dalry, in Ayrshire. The last mentioned may be a distinct
species. He further described two specimens of adherent Produc-
tidee, one from Scremerston quarry, Northumberland (near Berwick),
and one from Kinghorn, in Fifeshire, the characters presented by
which led him to refer them to the genus Chonetes.

5. “The Submarine Forest at the Alt Mouth.” By T. Mellard
Reade, Esq., F.G.S.

The right of the remains of trees on the shore at Great Crosby,
in Lancashire, to be regarded as representing a submerged forest
having been called in question, the author desired to place on record

Geological Society of London. 235

the results of an investigation which, he thought, would dispose of
all doubts on the subject. On cutting a trench through 1 foot
of peat and 14 inches of clay round one of the stumps, which had
an oak trunk lying by it, apparently in the position in which it had
fallen, the observers saw that roots were cut through all round,
running along near the surface of the clay, or penetrating it diagon-
ally ; while rootlets and tap roots descended vertically into the clay.
Several of the main roots were traced for a considerable distance
into the clay. On raising the stump out of the ground, the clay
showed numerous root-sections. The examination of the stumps
gave confirmatory results.

IIJ.—April 3, 1878.—Henry Clifton Sorby, Esq., F.R.S., Presi-
dent, in the Chair.—The following communications were read :—

1. “On an Unconformable Break at the base of the Cambrian
Rocks near Llanberis.” By George Maw, Hsq., F.L.S., F.G.S.

In a paper read before the Society on December 5, 1877 (Q.J.G.8.
vol. xxxiv. p. 137), Prof. Hughes referred to an observation made
by the author in 1867 as to the occurrence near Llanberis of an
unconformable break, indicating the base of the Cambrian; and,
while accepting the asserted existence of pre-Cambrian rocks in
North Waies, placed the base of the Cambrian in a very different
position, and maintained that the appearances described by Mr.
Maw might be accounted for by lateral pressure acting upon beds of
dissimilar texture and unequal hardness. The author had re-ex-
amined the section in question, and maintained his original interpre-
tation of the phenomena, which he regarded as the earliest indication
of the existence of a pre-Cambrian series. He accounted for differ-
ences observed in the supposed pre-Cambrian rocks at Moel Tryfaen
and Llanberis by regarding them as having undergone different
degrees of metamorphism.

2. “On the so-called Greenstones of Central and Eastern Corn-
wall.” By J. Arthur Phillips, Esq., F.G.S.

In this paper the author extended his investigations of the rocks
formerly mapped as greenstones, from the western (see Q. J. G. 8.
vol. xxxii. p. 155) into the central and eastern districts of Cornwall.
He described in detail various rocks from different parts of these
districts, the examination of which had led him to the following
conclusions. The numerous lavas which occur here, in addition to
the rocks met with in Western Cornwall, are so interbedded with
the slates and schists as to lead to the conviction that they are con-
temporaneous, and, although much altered, they closely resemble
lavas of more modern date. Sometimes they assume a distinctly
schistose character. The crystalline greenstones are more varied
and instructive than those of the western portion of the county ;
some of them are typical dolerites, while others are so altered as to
consist only of a granular indefinite base, traversed by indistinct
microlitic bodies. Their pyroxenic constituent is augite; and,
‘although many would call them diabases or melaphyres, the author
regards it as more logical to regard them as ancient dolerites.
Where these rocks are altered, the augite is usually changed into

236 Reports and Proceedings—Geological Society of London.

hornblende and viridite, while the felspar becomes cloudy, and
finally merges into a granular base. The crystals of augite are
often gradually replaced by an assemblage of felted microlites; in
other cases their outlines are preserved, whilst their substance is
replaced by hornblende, the rock being thus converted into a uralite
dolerite or uralite diabase. | When these rocks do not contain augite,
and are to a great extent composed of long bacillary hornblendic
crystals made up of parallel belonites, the ends of which are fre-
quently curved outwards, it is probable that hornblende was an
original constituent of the rock, which is therefore a true diorite.
Slaty or schistose greenstones are less frequent than in the western
districts, but on St. Cleer Down the “ hornblende-slates” graduate
imperceptibly from crystalline dolerites into clay slate; these are
not improbably of igneous origin. Some of the slaty blue elvans .
are identical in chemical composition with the dolerites, and may be
highly metamorphosed ash-beds, although, from some of their cha-
racters, it seems more probable that they are true igneous rocks.
The felspar in the brecciated slates is almost entirely plagioclase.
and is derived from the disintegration of greenstones. With regard
to the age of the rocks described, the author states that they are
generally older than the granite; for the vesicular lavas and many
slaty hornblendic bands are evidently contemporaneous with the
slates among which they are bedded, while the latter are often dis-
placed by the granite or traversed by granitic veins ; and, further,
the eruptive doleritic rocks which break through the sedimentary
beds never traverse the granite, but are often interrupted by it.

3. “The Recession of the Falls of St. Anthony.” By N. H.
Winchell, Esq. Communicated by J. Geikie, Esq., F.R.S., F.G.S.

The author’s purpose in this paper was to arrive at an estimate of
the date of the last glacial period from the rate of recession of the
Falls of St. Anthony, near the junction of the Minnesota and Mis-
sissippi rivers. He stated that the country is covered with deposits
of glacial origin, that between the present falls and Fort Snel-
ling, a distance of eight miles, the existing river-gorge has been
formed since the deposition of the newer Boulder-clay, and that the
old river-valley is filled up with glacial deposits. The gorge is of
very uniform character, being cut through hard limestones resting
on soft sand rock, both lying quite horizontally. The country was
settled in 1856, and the recession of the falls has since been very
rapid, its rate having been accelerated by the erection of saw-mills,
dams, ete. From the accounts of various travellers who have visited
the falls in the last 200 years, the author endeavoured to obtain an
estimate of the true rate of recession. Between the visit of Father
Hennepin in 1688 and that of Carver in 1766 he finds a recession at
the rate of 5-49 feet annually; between Carver’s visit and 1856 a
mean annual recession of 6°73 feet; and between Hennepin and
1856 one of 5:15 feet. The time-estimates for the cutting of the
gorge would be, according to the above means, 12, 103, 6, 276 and’
8, 202 years. The author considers the data upon which the second
of these numbers is founded the most reliable.

Correspondence—Ur. W. A. E. Ussher. 237

CORRESPONDENCE.

ON TERMINAL CURVATURE IN THE SOUTH-WESTERN COUNTIES.

Srr,—Notwithstanding its ten years’ rest, this subject seems to
retain its marrow as a bone of contention, judging from Mr. Mackin-
tosh’s letter in your last Number. Mr. Mackintosh seems to have
mistaken the object of my paper, as I had of his; for had I known
that “none” of the solutions proposed by him were “confidently
advocated,” by making the real object of my paper more prominent,
and dwelling less upon his hypotheses, I might have appeared less
controversial. The principal object of my paper was to deprecate
the invocation of glacial action in explanation of phenomena other- —
wise more reasonably explainable, and especially so in districts
where all direct proof of glaciation is wanting.

The keynote of my objection to all Mr. Mackintosh’s explanations
is struck in his declared scepticism in a “great surface waste and
contour moulding” of the South-western Counties during Pleisto-
cene times. How any geologist can calmly contemplate the distant
table-land of the Blackdowns from its insulated remnant Haldon,
and gazing across the broad valley of the Exe, excavated entirely
since the accumulation of the clay with flints, deny the vast contour
moulding and surface waste of Pleistocene ages, it is difficult to con-
ceive. I can only regard the hypotheses alluded to by Mr. Mackintosh
as untenable as regards the ‘“‘ Head” of Devon and Cornwall, having
a very wide acquaintance of the facts, and feel that I must hide my
diminished “‘ Head” under some more congenial covering than an
Arctic Sea or “immense ice-water lake.” My idea of a greater
elevation of land, accompanied by a more rigid expression of the
present causes of subaerial waste, not only suffices to explain the
formation of “Head” proper (i.e. the angular accumulation of stony
loam intermediate in time between the elevation of the beaches
and the submergence of the forests), but also fits into a necessary
sequence of physical changes.

I do not believe in uniformity of direction of curved-back lamine,
such directions being dependent on dip and strike of cleavage planes.
The effect of roots in wedging off laminz is very local, seldom
causing reversals extending more than a few feet from them. I
must, in conclusion, apologize to Mr. Mackintosh for having mis-
understood him about the direction of the cleavage planes on the
northern slopes of Brendon Hill; my objection to ice-passage on
the ground of the absence of terminal curvature, consistently with
his theory, on the north slope, was based on the assumption that the
laminz inclined in a southerly direction at a high angle, but not
approximating to the vertical. Any apparent controversial spleen
in the foregoing remarks must be attributed to that pardonable
partiality for their own specialities generally exhibited by local
geologists, and to no unfriendly spirit as regards Mr. Mackintosh.

W. A. E. Ussumr.

238 Correspondence—Messrs. H. E. H. & Wim. Pengelly.

TERMINAL ,.CURVATURE IN WEST SOMERSET.

Sir,—The accompanying short extract from Sir H. de la Beche’s
“Geological Observer,” p. 25, 2nd edit. 1853. contains remarks so
apposite on this subject, that I trust Mr. Mackintosh will allow me
to call his attention to them, if he should happen not already to be
familiar with them.

“The rain-waters not absorbed by the rocks, act mechanically on
the surface of the land, removing to lower levels such decomposed
portions of the rocks as their volume and velocity can transport.
The mixed effects of decomposition from atmospheric causes, and of
soaking of the surface on hill-sides, are often well shown in slate
countries, a certain depth beneath the soil exhibiting the turning
over of the edges of the slates towards the valleys ;—as it were the
tendency of the moistened matter of the surface to slide by its
gravity to the lower ground.

“The accompanying figure” (showing highly inclined strata with
the upper portion beneath the soil bent over into a curvature ‘against
their nap’) ‘ will illustrate this fact, one of much importance to the
observer, for without attention to it he might commit grave errors
as to the true dip of the strata, when only a slight depth of section
may be exposed on the hill-side. In the above figure the real dip
of beds is represented as the very reverse of that which might be
inferred from a hasty glance at the surface. Although it may be
supposed that the difference between this sliding down of the surface
towards the lower grounds and the true dip was always so apparent
as not to be mistaken, the depth to which this action has occasion-
ally extended is sufficient to justify great caution in many districts.”

It is to be remembered that ground that is now level may, at the
time when this curvature was produced, have been inclined towards
then-existing valleys. H. H. H.

THE GORRAN BEDS AND BUDLEIGH SALTERTON PEBBLES.

Str,—I observe that in the discussion, on the 20th March, 1878,
on Mr. Ussher’s paper on “The Chronological Value of the Triassic
Strata of the South-western Counties,” as reported in the “ Abstract
of the Proceedings of the Geological Society of London, No. 350,”
“Mr. Htheridge said that he had been able to ascertain from
specimens in the Penzance Museum that the Budleigh Salterton
Pebbles came from Gorran [printed incorrectly Gowan] on the
southern coast of Cornwall,” and that ‘“‘Mr. Whitaker stated that
he had himself, on lithological grounds, suggested the Gorran
Haven region as a source for the Budleigh Salterton pebbles.”

These statements interest me a good deal, since they are con-
firmatory of those contained in the following quotation from a paper
which I had the pleasure of reading to the Plymouth Institution as
long ago as 380th March 1865 :—“ Having learned that Mr. Peach
had lodged in the Penzance and Truro Museums such of the fossils
[from near Gorran] as he had collected, Mr. Vicary, Dr. Scott, and
I went into Cornwall early in July last (1864), for the purpose of
examining them and the rocks in which they were found. The

Correspondence—Mr. J. H. Jennings. 239

fossils are in many cases so fragmentary or indistinct that identifica-
tion is by no means easy; nevertheless, we succeeded in detecting
among them several specimens of one of the Budleigh Salterton
species of Brachiopoda. Having been furnished by Mr. Peach with
all needful information, we were so fortunate as to secure the
assistance of one of his old collectors, who conducted us to the
fossiliferous beds of the Great Cairn and Great Peraver, near Gorran
Haven. In the Peraver, we succeeded in finding fossils having the
same general facies as those of the “ pebble-bed,” and inhumed in
quartzites identical in structure and even in hue with the pebbles of
South-eastern Devonshire.” (See Transactions Plymouth Institu-
tion, 1864-5, vol. i. pp. 22-8.)
Torquay, 4th April, 1878. Wu. PENGELLY.

ON THE ORIGIN OF A QUARTZITE BOULDER FROM THE BUNTER
CONGLOMERATE, NOTTINGHAM.

Str,—A short time ago it was my good fortune to find, in a
heap of road-metal, near Nottingham, a liver-coloured quartzite
boulder, no doubt derived from the Bunter Conglomerate of the
district, which exhibits on its fractured surface a well-defined con-
cave cast of Orthis redua—a Caradoc fossil that is, I understand,
by far the most frequent species in the quartzite pebbles of the
Triassic shingle beds of Budleigh Salterton, Devon, and of similar
deposits in the North of France.

In recording the occurrence of the above fossil in this locality,
I am content to leave the question whence this and similar pebbles
in our Bunter Conglomerate were derived for the consideration of
those who are more competent than myself to offer an opinion on
the subject.

Norrineuam, March 18th, 1878. J. H. Jennines.

(Gps ICIe IG JA IS Soe

—_—<—_—_

JOHN ROFE, C.E., F.G.S., ETC.
Born, 14 Ocroper, 1801. Drep, 11 Aprit, 1878.

We regret to record the loss by death of an excellent geologist,
a much valued friend, and a frequent contributor to this Journal.

Mr. Rofe was born in London, Oct. 14, 1801, and was educated at
Enfield, by the late Mr. Cowden Clarke, and afterwards at Reading
with the Rev. Dr. Williams.

He studied engineering under his father Mr. John Rofe, C.E.;
and afterwards, in partnership with him, carried out many im-
portant public works, notably the Birmingham Gas, and Water-
Works; the Reading Gas-Works; Gas and Water Engineering
Works were also carried out by Mr. Rofe for the towns of Leicester,
Guildford, and Boston. On several occasions he gave valuable
evidence in Committee before the House of Commons, with reference
to public Towns Water Works and Gas Companies Bills, in which
his sound geological knowledge proved of great service to him.

On the 26th June, 1827, he married the daughter of the Rev.
Bartholomew Goe, Vicar of Boston, Lincolnshire, and settled in

240 Obituary—John Rofe.

Preston as Engineer to the Gas Works, a post which he held for
twenty-five years. ;

While resident in Preston he took a very active part in the
Literary and Philosophical Society of that town, and in December,
1845, a service of plate was presented to Mr. Rofe by the members
“in acknowledgment of the zeal and ability with which he had pro-
moted the establishment, progress, and success of that Institution.”

He had only one son and daughter; the latter married Dr. Fearn-
side of Preston; the former (the Rev. John Rofe), a young man of
high promise, after graduating at Cambridge, 1850, received in 1859
from the Master of his College (St. John’s), the offer of an Indian
Chaplaincy, which he accepted. He officiated as Chaplain to Lord
Canning (then Governor General of India) during a tour in the North-
West Provinces; and finally as Chaplain to Dr. Cotton, Bishop of
‘Calcutta—with whom, whilst on a visitation tour, he died in 1861,
at the early age of 34 years. ;

This severe family bereavement had no doubt a most depressing
influence on so amiable a man as Mr. Rofe, and caused him to spend
much of his time in the retirement of his library or engrossed in
the study of his fine private collection of Crinoidea from the Carbo-
niferous Limestone of Clitheroe. Having resigned his official duties
at Preston from ill-health, he devoted himself to a careful study of
the internal anatomy of the fossil Echinodermata, and his valuable
researches will be found embodied in a series of papers printed in
this Macazinz, a list of which is subjoined.

For some years he resided at 15, Abbey Place, St. John’s Wood ;
but afterwards removed to Lancaster, where he was elected Presi-
dent of the Lunesdale Naturalists’ Field-club; his health, however,
did not long permit him to retain the office. For the last few years
he has resided at Leamington, but of late he has been prevented by
failing eyesight from carrying on his favourite microscopic re-
searches. In February last he presented his rich collection of Crin-
oidea and other fossils from the Carboniferous Limestone (number-
ing upwards of 1,500 specimens) to the National Museum.

He died at his residence, 9, Church Hill, Leamington, on the 11th
day of April, at the age of 77 years.

The following are the titles of Mr. Rofe’s scientific papers :—

1. ‘“‘ Observations on the Geological Structure of the Neighbourhood of Reading ”’

(read Feb. 26, 1884), Trans. Geol. Soc. 2nd series, vol. v. 1840, p. 127.
_ Proc. vol. i. p. 72.

2. “ Description of a New Species of Actinocrinus from the Mountain-Limestone of
Lancashire” (with 3 woodcuts), Grou. Mac. 1865, Vol. II. p. 12.

3. ‘Notes on some Echinodermata from the Mountain-Limestone,” etc. (with a plate),
Grou. Maa. 1865, Vol. II. p. 245.

4. “ Notes on Coal and Cannel,” Gro. Mac. 1866, Vol. III. p. 208.

5. “ Note on the late Colliery Explosions,” Grou. Mac. 1867, Vol. IV. p. 106.

6. “Note on the Cause and Nature of the Enlargement of some Crinoidal
Columns” (with 5 woodcuts), Grou. Mac. 1869, Vol. VI. p. 341.

7. “On some supposed Lithodomous Perforations in Limestone Rock” (with a
plate), Grout. Mac. 1870, Vol. VII. p. 4.

8. “Notes on the Crinoidea”’ (with a plate), Grou. Mac. 1871, Vol. VIII. p. 241.

9. “Further Notes on the Crinoidea”’ (with a plate), Grou. Mac. 1873, Vol. X. p. 262.

10. Presidential Address to the Members of the Lunesdale Naturalists’ Field-club,
25th Feb. 1873: ‘On the Geology of the District around Lancaster.”’—H.W.

THE

GEOLOGICAL MAGAZINE.

NEW SERIES. DECADE tl. VOL: V:
No. VI—JUNE, 1878.

ORIGINAL ARTICLES.

————

I. —PHyYsIoGRAPHY.
By C. Luoyp Morean, F.G.S., A.R.S.M.

HE artist who is illustrating a great theme upon a large
spread of canvas finds it necessary from time to time to lay
down the brush, with which he is accurately filling in the more
delicate minutiz, that he may retreat to a distance and view his picture
as a whole. It is essential to the higher development of his art
that he should not omit this comprehensive survey. The same
thing holds good in Literature and Science, as well as in Art. The
historian must, from time to time, take a fresh survey of History as
a whole. If he neglect to do so, the group of figures to which
he devotes his special attention will certainly not take up its true
position among the other groups that appear on the canvas of
History. The man of science, also, should not forget that he is,
according to his individual bent or capacity, aiding in the con-
struction of a great Philosophy; and he should now and again turn
aside from the microscope, or lay down the hammer, to take a
more comprehensive survey of that Philosophy, whose aim it is to
comprehend and consolidate the widest generalizations of Science.
A rude attempt at such a survey of the principles of geology and
the bordering branches of science will be found in the following
pages. They are from the notes of a lecture which formed the last
of a course delivered before a school audience. In that lecture I did
my best to give a rough sketch of that chain of events by the study
of which we may build up a history of the Earth, while I en-
deavoured at the same time to lead my hearers upwards from the
simple to the complex: for I hold that the teacher of science should
lead his pupils from the well known, through the less known, to
the unknown. Taking a few simple and obvious facts as a basis,
he should first test whether those whom he teaches really know
them to be facts, and then, carefully building upwards, seeing that
each stone of his superstructure rests securely on one which has
before been firmly laid down in its true place, he should mount
slowly and surely, until, at last, he reaches that rare atmosphere of
the unknown in which, for the present at least, no man may build.
Standing by the sea-side, then, let us inquire of Nature con-
cerning the things which we see around us. The waves roll in
upon the shore, the wind blows freshly in our faces, a heavy
DECADE II.—VOL. V.—NO. VI. 16

242 CO. Lloyd Morgan—Physiography.

storm-cloud hangs over the distant horizon, at our feet is a little
streamlet running over the sands to the sea; behind us is the
white chalk cliff, capped with sand and clay.

How come these waves, and what are they doing? shall be
our first question. The answer to the first part of the question is
so obvious that a child will not hesitate to reply, that it is the
wind which produces the waves. At first a mere cat’s paw on
the surface of the sea, the growing ripples are, as the wind continues,
hurried onwards, increasing both in length and breadth, and, where
the water is deep, in velocity of motion, until they become the great
waves, some 14 feet high from trough to crest, which we see on
our coasts during a storm, and finally, if they have a fair field,
develope into ocean billows, 26 feet high in the Atlantic, 40 feet
high in the Southern Ocean. In the open sea the water is not
carried forward by this wave motion. We may watch the sea-bird
rise and fall as the wave passes under her. She is not carried
forward on its summit. But when the wave reaches shoal-water, in
the neighbourhood of land, the lower part is retarded by friction
against the bottom, while the upper part hurries on, and the wave
breaks, and rushes up the shore, the under water racing back and
tearing up the beach in its backward course. It is in this way
that the sea has such power in grinding down the rocky materials
which fall to the base of our island cliffs. Along the Chesil Beach
the pebbles are carried forward fifteen miles by the action of the
waves, and as they grind over each other in their westward course,
they become smaller and smaller.

Here then we obtain an answer to the second part of our question :
What are the waves doing? They are beating backwards and
forwards the matter which falls from the cliffs, until it is broken
up and rolled into a rounded pebbly beach. But they are doing
more than this. They are battering at the cliff itself, and, aided by
rain, and frost, and wind, are eating away our island shores. The
force with which the waves dash against the cliffs is at times
enormous, having been known to reach a pressure of more than
three tons on the square foot. During the hurricane which swept
over Barbadoes in 1780, cannon which had long been lying sunk
were washed far up on shore. ;

In some parts of England the sea is advancing rapidly on the
land. Prof. Huxley, in his excellent little book on Physiography,'
quotes, as an instance, the fact that Reculver church, which in the
time of Henry VIII. was a mile from the sea, is now only preserved
from the destructive action of the waves by a stone breakwater
made by the Trinity Board. Not long ago, I walked along the
coast from Herne Bay to the Reculvers. The rapidity of the waste
was clear. In many places portions of the path had been carried
away. Masses of grass-covered earth, lying at the foot of the
vertical portion of the cliff, showed how recent had been the pre-
cipitation from above; while the clean-cut face of the cliff, and the
sharp forms of the projecting ridges and pinnacles of the clay,

1 8yo. pp. 884, with 5 plates and 122 woodcuts (Macmillan & Co., London, 1878).

C. Lloyd Morgan—Physiography. 243

showed that since they were left in their present position, they
had not suffered for long the attacks of rain and wind. Great
cracks at the surface, here and there, showed that destructive action
was still in progress; and when I looked at the lately fallen blocks
of earth below, I felt that it was possible that the grass tufts, on
which I stood, might be the next to fall amidst the ruins beneath
me. But though the action of the weather was thus clear, the
sea-waves, which alone permitted that action to continue, were
not idle. The brown colour of the sea for some distance from
the shore gave evidence of this, and while I stood upon the beach,
I saw several projecting blocks of clay wasted by more than half.

In Scotland and Western England, where the rocks are hard,
the advance of the sea upon the land is quite imperceptible. All
the beauties of our coast scenery, our bold headlands and sweeping
bays, result from this unequal action of the sea upon the harder and
softer rocks of which our island is built up. But little observation
is necessary to make it clear that, along any coast-line, the pro-
montories are composed of hard rock, the bays of a softer material.
Sea-side scenery is, therefore, a joint product of wave action and
the geological structure of the coast. We must not forget, however,
that it is only along its margin, where it beats upon the shore-line,
that the sea is an agent of denudation. Throughout its great extent
the ocean is the area of deposit and construction, just as the land
is the area of destruction and waste. Beneath the sea the products
of that waste come to rest. Strange as it sounds, the sea is the
cradle of the land. Beneath the waters of the ocean are formed
those layers of sediment which will some day be raised above the
waters to form the framework of new continents.

From the answer to our first question, then, we learn that the
waves are advancing upon the land, and thus producing our coast
scenery, and that they are caused by the winds.

Let us next consider the streamlet at our feet. What is it doing,
and how comes it here? That little streamlet, if we will but listen
to it, can tell us much about what the great rivers of the earth
are doing. Let us learn from it. In the first place, then, we see
that this miniature river! is gradually changing its course. The
main current strikes against one bank more than the other. The
result is that this bank is forced to recede. Its tiny cliffs are
undermined by the action of the stream, and the upper portions,
now and again, topple over with a little splash into the water.
Here we have in miniature that which may be seen on an enormous
scale on the Mississippi and the Amazons. Large vessels may there
be made to rock by the waves created by the fall of great masses
of the concave bank, the river having in this way advanced upon
the land hundreds of yards, and, in some cases, even, several miles,
within the memory of living men.

This shows how a stream cuts its way sideways into the land.
This is not, however, the most important part of what a river does.
If we follow our stream a little way inland, we shall discover that

1 Miniature Physical Geology, Natwre, March 8, 1877.

244 C. Lloyd Morgan—Physiography.

it cuts its way downwards and cuts its way backwards. Both modes
of action go on, as a rule, at the same time; but sometimes one,
sometimes the other, is most obvious. Of the first, the Canon
of the Colorado offers an example on the grandest scale. This
great ravine is about 300 miles long and, in places, more than a mile
deep. There can be no doubt that it has been entirely cut down
into the desert plateau by the action of the river. How this was
effected we learn, to some extent, from the following sentence in the
American report on the river, ‘“‘The water of the Colorado,” says
the reporter, “holds in suspension a large amount of fine siliceous
sand, sharp as emery, that eats away the valves” (connected with
the machinery of the steamer) “as rapidly as it could be done
with a file.” It has probably been with the aid of this sand that
the river has cut down its deep trench.

Of a river cutting its way backwards, the Niagara is the grandest
example. At the Falls the water tumbles over a ledge of lime-
stone which rests on a thickness of shales. By the action of the
spray which rises from the waterfall, and partly by the power
of frost, the shale is rotted away, and thus the limestone is under-
mined. It is in part owing to the undermining action, that visitors
can proceed a little way under the falls. To do so is well worth
a wetting: a whole river takes its mighty leap, and falls with a
bewildering roar at your very feet, and if it be winter giant icicles
hang above your head. When the “under-cutting” has gone on
for a certain time, huge blocks of the limestone tumble with a
crash to the base of the waterfall. In this way the Falls of Niagara
are working backwards, at the rate of about one foot a year, towards
Lake Erie. Only the other day it was stated in Nature that, on
November 17, 1877, a large section of the rock towards the Canada
shore fell with a tremendous crash, and that during the night a
still larger area went down.

But what becomes of all the material dug out by the stream
as it cuts its way sideways, or downwards, or backwards? If we
watch any little rill which falls into a pool on the sea-shore,
we shall soon find out. We shall see that the sand and other
material which it carries are built up into a little delta, while some
of the finest material is spread at large over the bottom of the pool.
Large rivers carry vast quantities of mud and sand and silt (much
of which is washed off the land by the rain) to the sea. Experi-
ments of mine on the Thames at Surbiton show that in fine
weather, when the river was low and fairly clear, solid matter
in suspension was being carried seawards at the rate of 9767
tons per annum; while, when the river was in extreme flood,
matter at the rate of 524,940 tons per annum was passing
in this way down towards the sea. With the great rivers of the
world of course the amounts are still more enormous. Sir Charles
Lyell calculated “that if a fleet of more than 80 Indiamen, each
freighted with about 1,400 tons weight of mud, were to sail down
the Ganges every hour of every day and night for four months
continuously, they would only transport from the higher country to

C. Lloyd Morgan—Physiography. 245

the sea a mass of solid matter equal to that borne down by the
Ganges in the four months of flood season.” All the matter
carried down in this way is built up, layer upon layer, into a vast
delta deposit, or strewn over the bed of the ocean. Of such layers
much of the crust of the earth, the sand and clay at the top of the
cliff behind us for example, is composed.

But besides the matter carried down by rivers in suspension, a
vast amount is carried down in solution. Take the Thames for
example. For every grain transported mechanically, more than
20 grains are carried down chemically. Every gallon contains some
20 grains of lime salts, and about two grains of common table salt,
or Chloride of Sodium. These also are carried out into the sea, in
which the Chloride of Sodium, along with certain other salts,
accumulates on the evaporation of the water, and thus forms the
brine of the ocean, while the Carbonate of Calcium is separated by
living creatures and built up into some sort of pure limestone. Of
such limestones also much of the crust of the earth, the chalk of the
cliff behind us for example, is composed.

We have thus seen what the streamlet is doing. It is aiding the
rivers of the world to carve out valleys, and it is carrying seawards the
fine mud and sand which result from its own work and that of rain,
to contribute to the framework of a future continent. And how
comes it here? Directly or indirectly from rainfall. Whether its
source be a spring, or the collected waters from a sloping hill-side, it
matters not. Without rainfall, such as is now pouring from the
distant storm-cloud, the streamlet could have had no existence.

Another question therefore suggests itself: What is this rainfall
doing, and how comes it here? If we walk along the shore for a
little distance, we may perhaps see (if there is beneath the cliffs any
clayey material containing flat stones) small pillars of earth, each
capped by one of these flat stones. These are little monuments of
rain action. Rain falls upon the surface and runs off towards lower
levels; as it runs, however, it carries with it a little of the fine
clayey material. Thus it lowers the surface. But where there is a
flat stone, the surface is protected from the softening action of rain-
_ drops, just as a house is protected by its roof. The soil beneath the
stone is not carried away, and the miniature earth pillar stands out as
a monument. In Switzerland there are, in several places, earth
pillars 50 or 60 feet high, which have been formed in this way.

But it is not only where there are earth pillars that the rain is
exercising a denuding action upon the land. If we go out into the
fields on any rainy day, we may watch how the soil is literally
flowing downwards to the sea. Few fields are perfectly flat, and
the rain which falls upon the surface tends to drain off at the lowest
possible level. But if we examine the water which is thus on its
way down the field, we shall at once see that it is not clear, that it
carries with it some of the soil. Much of the rain, of course, sinks
into the ground. But before it does so it is nearly sure to trickle a
foot or two over the surface. Hven if it only runs a few inches, it
must bear with it some of the soil for this distance, and there leave

246 C. Lloyd Morgan—Physiography.

it. If the rainfall continue, the soil is soon carried a few inches
further; and it always travels in one direction from higher to lower
levels. Our field may be separated at its lower end from another by.
a wall, which will check the downward progress of the soil. If
this be so, we shall often find that, from the accumulation of this
soil, a child may look over the wall on that side of it which faces up
hill, while a full-grown man may have to stand on tiptoe to gain the
same advantage on the lower side. Or perhaps at the bottom of the
field there may be a ditch; that ditch may communicate with a
streamlet, and the streamlet fall into a river. Some of the soil of
the field is thus carried by every heavy shower of rain into the ditch,
and thence into the river. After a wet day we shall find that all
the tiny rills, the little rivulets, the streams, and the great rivers
themselves, are muddy and thick. This mud is nearly all derived
from the soil of the land which lies in the river-valley. Thus the
land is always flowing downwards to the sea; not a particle can get
up again when once it has flowed even a few feet in its downward
course: and this action is going on wherever rain falls upon the
surface of the land.

But though the surface layer is, in this way, being constantly
washed off the fields, the soil does not lessen in quantity. or as fast
as material is carried away by the rain, so fast does the same agent,
aided by weathering action, prepare fresh soil, to be treated in a
similar manner. At the same time, we must remember that, though
the amount of soil does not grow less, the amount of land above the
waters of the ocean does diminish. Does this seem strange? A
rough analogy may serve to make it clear. A man possesses a
certain amount of money, most of which is in the bank, and a small
amount, for immediate use, in his waistcoat pocket. As fast as his
ready cash disappears, he draws a cheque on his banker, and in this
way his waistcoat pocket has a more or less constant supply.
Practically speaking, therefore, his ready cash does not diminish,
though his balance at the bankers does not remain equally constant,
but decreases day by day, at a rate which would shortly lead to
bankruptcy, if he were not careful that there should be a supply
equal to the demand. Now the soil is the ready cash, and the strata
of England the balance at the bank. Rainfall is continually tending
to diminish the amount of soil or ready cash, which is made good by
a fresh supply from the bank. It is perfectly obvious, however,
that the balance at the bankers must decrease, and that in the course
of ages England must be entirely washed away into the sea of
geological bankruptcy, unless the bank receive a fresh supply ;
unless, in other words, by the force of elevation, fresh land be
raised, from time to time, above the waters of the ocean.

With regard to the influence of rain on the physical aspect of a
country, it may be said that, viewed on a large scale and in a general
way, this agent exercises a softening effect on scenery; in those
areas where the strata are of a soft and easily yielding nature, the
work of rain as an Harth-sculptor is to cause the land to assume a

C. Lloyd Morgan—Physiography. 247

gently undulating form, and to extend in breadth those valleys
which rivers are always tending to extend in depth. On those
rocks, however, which are of a harder nature, rain has less absolute
power, but even here it renders the scenery less rugged; less
sublime perhaps, but more beautiful.

And how comes this rain? We know that it falls from the
clouds. We know too that these clouds are formed when the air
above is cooled so much that it can no longer hold in solution all
the vapour of water which it has borne in an invisible form from
afar. The rain, therefore, comes from the vapour of water existing
in the wind. And how comes it to exist in the wind? It is ob-
tained from the Atlantic Ocean. Thither then we must travel in
thought and try and picture to ourselves what takes place when the
visible liquid water is converted into the invisible gaseous vapour
of water. Now it is quite evident that some force is overcome—
some binding force which drew the particles of water closely together.
This force is cohesion. It may be likened to a strong man who
holds the watery particles in bondage, not indeed so severe as that
of the terrible ice-king of the Arctic and Antarctic regions, for they
are allowed free motion among each other, and are not locked in the
solid state, but still bondage chaining them down to the limits of the
ocean. This strong man will not loose his grip until he be conquered
by a stronger than he; and on the Atlantic he meets with that
stronger man whom we call heat.

Sun-heat sets free the particles of water from the bondage of
cohesion, and allows them to escape into the air. But the mastery
is not gained without an effort, and the value of this effort has been
calculated. ‘To emancipate nine pounds weight of water particles,
an amount of energy has to be expended, equal to that of lifting a
ton to the top of a precipice 2900 feet high.’ But just as, when two
wrestlers struggle together, neither can master the other without a
true waste of his substance taking place, a waste that has ere long
to be made good by the absorption of a certain amount of mutton or
beef, so too on the Atlantic, during the struggle between cohesion
and heat, a certain amount of the latter is consumed and disappears.
The amount of heat so expended has also been calculated. In
setting free nine pounds of water particles an amount of heat
disappears sufficient to fuse 45 lbs. of cast iron.’

To take leave of metaphor, this amount of heat is expended in
overcoming cohesion and tearing asunder the particles of water.
The vapour particles thus formed, kept separate from each other by
heat, are carried by the wind to our shores; there the air in which
they float is cooled; the heat is now insufficient to overcome the
force of cohesion, and the water particles, no longer held apart,
clash together, and as they do so they generate by the shock as
much heat as was expended before in tearing them asunder. All
the heat which disappeared—was rendered latent or hidden—when
the vapour of water was raised from the Atlantic, is set free or
rendered sensible when condensation takes place. For every nine

1 These are two different ways of stating the same fact.

248 C. Lioyd Morgan—Physiography.

pounds weight of cloud formed in our skies, an amount of heat is
set free sufficient to melt 45 lbs. of cast iron.

A valuable lesson may be learnt from this behaviour of water and
water vapour. When the liquid water became gaseous vapour, a
certain amount of heat energy disappeared. But it was not de-
stroyed. It was converted into another form of energy which we
may call the energy of separation. The particles were forcibly
separated from one another, and a certain amount of energy was
necessary to keep them apart. Presently, however, they clashed
together again, and the energy of separation was reconverted into
the energy of heat. The amount of heat given out was exactly
equal to the amount of sun-heat absorbed. Day by day fresh
experiment and observation make clearer this great law of nature:
that by no means at our disposal can we either destroy or create
energy. We may change it in a number of ways. We may con-
vert chemical separation into electricity, this into mechanical motion,
and mechanical motion into heat. But we can neither call into
existence or put out of existence any portion of the energy of the
universe, any more than we can call into existence or put out of
existence any portion of the matter of the universe.

One more fact must be noticed. Though the same amount of

heat is given out by the condensation of the aqueous vapour, as was
absorbed on the Atlantic during its formation, it is no longer useful
in the same way. It does not possess the power of again converting
water into water vapour. It has become degraded. It is the same
in amount, but different in value. The water which turns a mill is
the same in amount, whether it lies above or below the water-wheel ;
but it differs vastly in value. That above the mill is useful to the
miller: that below the mill is useless. It is the same with energy.
Just as water tends to run down from higher to lower levels, so does
energy tend to run down from higher to lower forms. All forms of
energy tend to be degraded to heat uniformly diffused throughout
space. :
To the energy of sun-heat, then, we owe the existence of vapour
of water in the wind. And to what do we owe the wind itself?
To the same cause. On any winter’s evening, the colder the better,
we may make the following experiment, first performed by Franklin.
When the dining-room is warm, but the hall outside cold, we may
throw open the door to its full extent. On holding a lighted candle
in the doorway near the top, we shall find that the flame is blown
outwards: on holding it near the bottom, we shall find that it is
blown inwards: midway between the top and the floor, the flame
will burn steadily. The cause of this is obvious when we remember
that warm air is lighter than cold air. When the door is opened,
warm air rushes out near the top, and, to supply its place, cold air
rushes inwards along the floor. The two currents are divided by a
calm.

At the seaside we may watch the same sort of experiment per-
formed on a larger scale by nature. In settled summer weather
sailors count on a sea-breeze in the morning, and a breeze from the land

C. Lloyd Morgan—Physiography. 249

at night. The cause of these land and sea-breezes, with which every
yachtsman is acquainted, is simple. In the morning the sun shines
alike on land and sea: the land, however, most readily takes up the
undulations of heat. The air above the land thus warmed expands,
and forms an upward current, while a refreshing breeze comes along
the surface from the sea, just as a cold current passed along the
floor from the hall.

At nightfall the reverse is the case. The sun withdraws his rays
from land and sea: but the land, which was the first to be heated in
the morning, is the first to cool in the evening. Soon it is as cool as
the sea. Hre long it has become colder than the sea. And the current
now sets outwards from the land. We have changed the conditions.
We have brought a refrigerator into the dining-room, and the lower
cold current now sets outwards into the hall. It is, of course, under
ordinary conditions, only the under current which we on the earth
feel. The upper current is far above our heads. A French balloonist
(Tissondier) rose from Calais into the upper current, and was
carried far out to sea; on descending he entered the under current,
which bore him safely back to Calais.

The same laws are seen in operation in the Indian Ocean. There
for half the year the North-east Monsoon which blows from the
continent of Asia is the prevalent wind. During the summer, how-
ever, it is forced back by a South-west wind, caused by the great
upward draught over the glowing plains of Central Asia.

Far away on the broad Atlantic and Pacific Oceans, we may see
the same thing on a scale so magnificent as to form a healthy and
vigorous circulation for the whole world. In the great system of
winds, of which the trade winds are the most constant, we have
mighty currents of air which sweep from pole to pole, and are the
very life of the earth over which they pursue their ceaseless course.

Thus the existence of the winds is due to sun-heat.'

Let us pause here for a moment to see what we have learnt. We
have seen that the waves which beat on our shores, and denude our
coast-lines, are due to the winds; that the rivers which cut down
trenches into the earth are due to rain, which is itself brought to us
as vapour of water by the winds; and we have seen that both the
formation of water vapour, and the existence of the winds, are due
to sun-heat. This sun-heat is therefore the highest link we have yet
reached in the chain of causation. We have also seen incidentally that
the sand and clay at the top of the cliff were built up of mud and
sand grains, carried down mechanically by rivers to the sea: and that
the chalk has been separated by living creatures from the sea-water
to which the lime had been carried down in solution by rivers. The
question—how came this life upon the earth ?—now arises. It will
not however be discussed here. It is enough to state that it is
almost universally believed by those competent to give an opinion,
that all life forms have come into being by a process of evolution
from primitive organic germs. It may be noticed, however, that all
life, whether vegetal or animal, is made possible only by solar

1 Their direction is modified by the rotation of the Earth.

250 C. Lloyd Morgan—Physiography.

energy. Animals depend on plants, directly or indirectly, both for
the food they eat and for the air they breathe. In the absence of
sunlight plants would be unable to decompose the vast quantity of
carbonic acid which animals breathe forth: and thus their source
of carbon and our source of oxygen would be cut off.

Another question must now be put and shortly answered. The
sand and clay and chalk which form our cliff were laid down
beneath the sea; how come they now to form dry land? Now it is
clear that one of two things must have taken place: either the level
of the sea has been depressed or that the land has been raised.
Geologists do not hesitate to say that it is the land which has under-
gone the change in level, while the sea has remained stationary.
The sea is, in fact, more stable, more constant, more ancient than
our oldest continents. All land is, on the other hand, subject to
changes of level. In the Himalaya mountains shells, which once
lived in the sea, are found at an elevation of 16,000 feet above the
level of the ocean. The northern part of Scandinavia is even now
slowly rising, while the southern portion is undergoing depression.
But how? There lies the question.

It is now well known that the Harth is, in the interior, in an in-
tensely heated condition. In deep wells and mines the temperature
rises about 1° Fah. for every sixty feet we descend. The melted
lava poured forth during volcanic eruptions gives us some idea of the
temperature comparatively near the surface. The centre of the
Earth must then be hot beyond conception. But it is gradually
cooling. Heat is flowing outwards through the crust into space: the
cooling of the Earth is accompanied by contraction of the mass of the
Earth: and unequal contraction produces areas of depression and
elevation.

Is this clear? Perhaps a comparison of great things with small
will make it clearer. The human mind seems at times to fail to
grasp facts which are, in truth, simple, but which from their magni-
tude are hard of conception. If, for instance, we stand on a high
peak and look out over a portion of a great mountain chain, and see
the grand summits standing out along the central ridge, it is difficult
to conceive how this grand upheaval could have been produced; and
perhaps the mind, wearied with the attempt to grapple with a subject
almost too great for its powers, finds relief in the thought, that the
mighty elevation was due to some great cataclysm or convulsion of
Nature, concerning the cause of which—as a matter beyond our ken
—it would be rash to speculate. And if it were then suggested that
mountain chains, such as that in the midst of which we were standing,
must be the inevitable result of the contraction of a cooling globe, it
may be that our understanding would reject a conclusion which it
could not at once grasp.

But if when we have left the mountain top, we take up a withered
apple of last year’s growth, the consideration of its surface may help
us to understand that which before was so hard to comprehend.
When we plucked that apple, a year ago, its surface was smooth, and
the skin was stretched tightly over the fruit beneath. But since that

C. Lloyd Morgan—Physiography. 251

time the apple has shrunk in size, the fruit having contracted within
the skin, which, no longer tight and glossy, is now wrinkled and
puckered up.

But just as in the apple, so too in our planet, there is an inner
portion which is contracting, and an outer portion which does not
shrink: and as surely as the earth is losing heat by zadiation into
space, her mass contracting and her size growing less, so surely must
the outer portion become puckered up, the most prominent wrinkles
forming what we call mountain ranges.

While swn-heat, therefore, enables rain, rivers, and the sea to
denude the land and to combine in the formation of new continents,
earth-heat causes a fresh supply of land to be raised above the waters.
Were it not for this earth-heat England, as already mentioned, would
during the course of geological time be entirely washed into the
ocean of geological bankruptcy. All geological action, except that
due to the tides, is brought about by sun-heat or by earth-heat.

Before inquiring what is the cause of this sun-heat and this earth-
heat, there is one more question to be answered. Of what does the
air, the water, the cliff, ultimately consist? Are earth, air, and
water, as the ancients believed, elements? No. The air is composed
chiefly of a mixture of a gas called Nitrogen with one-fifth of its
volume of Oxygen. It is not difficult, as will be seen in Professor
Huxley’s book, for the chemist in his laboratory to separate these two
gases. Nor has he much difficulty in splitting up water into the two
gases oxygen and hydrogen; while the further task of ascertaining
of what the solid crust of the Earth is composed, though it requires
more labour, is by no means beyond his powers. But whereas water
contains but two elements, in the solid crust of the earth there are
about sixty-five. But what are these elements? They are simple
bodies which resist every effort of the chemist to decompose them
into simpler bodies. Many chemists, however, believe that, though
we cannot by any means at our disposal thus split them up, this is
only because the means at our disposal are limited, and that, at an
intensely high temperature, all would be found to consist of one
primitive form of elementary matter.

One of the most striking results of modern scientific inquiry is
the discovery, by means of the spectroscope, that there exists in the
Sun’s photosphere some sixteen or seventeen at least of the so-called
elements, with which we are acquainted on the surface of our earth.
Herein lies one of those many bonds, by which we are connected
with our central luminary. The cause of these bonds; the origin of
sun-heat and earth-heat ; and of the Sun and the Harth themselves,
now require elucidation.

According to the now-generally-accepted theory, known as the
Nebular Hypothesis of Kant and Laplace (and it must be noted that
we are here passing from the well known to the less known), our
solar system was formed from a diffuse nebulous mass. We must
imagine that this rotating spheroid mass once extended to the furthest
limits of the solar system; beyond the orbit of Neptune. It radiated
heat freely into space, and under the force of gravitation underwent

252 C. Lloyd Morgan—Physiography.

contraction. And as it contracted it left behind it rings of vapour
which, breaking up, formed secondary rotating spheroids, themselves
contracting, themselves leaving behind them rings, forming tertiary
spheroids, themselves passing in their orbits round the central mass.
That central spheroid mass is the Sun; one of the secondary rotating
spheroids is the Harth, the Moon being a tertiary spheroid. The
Harth-planet thus formed was gaseous; but as time rolled on, it
passed through the liquid state, to the more or less solid state, which
it at present possesses.

Sun-heat is therefore the result of the condensation of the primary
spheroid : earth-heat the remnant of that produced by the condensa-
tion of a secondary nebulous spheroid. :

And now comes the question, how was the rotating nebulous
spheroid formed ?

If we take a small piece of lead and deal it a number of heavy
blows with a hammer, we shall find that the lead becomes hot. If
we continue to hammer for ten minutes, we shall find that the lead
becomes too hot to hold. Now what is the cause of the heating of
the lead. Simply this: when the lead is struck, the motion of
the hammer is suddenly stopped: but the motion is taken up in a
new form by the particles of the lead, and this new form of motion
is heat. The visible motion of the hammer is converted into the
invisible molecular motion of heat: for heat is simply the rapid
vibration of the ultimate particles of matter.

When a bullet is shot from a rifle against an iron target, the
rapidity of the motion is suddenly arrested ; heat is developed; and
this heat may in some cases be sufficient to melt the point of the
bullet. In the same way the immense iron shot, hurled from our
modern pieces of ordnance, cannot fail to be intensely heated, when
they strike against the sides of such a ship as the Infleaible. It is
quite conceivable that a shot or bullet of lead might be projected
with such violence as to be, not only fused, but converted into vapour
on striking the target. For when the motion of heat becomes ex-
tremely violent, the particles of matter are shaken asunder, and
a vapour is formed.

We may take the velocity of a rifle bullet to be 225 feet in a second.
The velocity at which the Harth moves through space, as she travels
round the Sun, is about 19 miles in a second. If we imagine that
the Earth were suddenly to strike a huge target, the heat generated
would be sufficient, not only to fuse the Harth, but to reduce it in
great part to vapour. ‘The amount of heat thus developed would
be equal to that derived from the combustion of fourteen globes of
coal, each equal to the Harth in magnitude. And if, after the stoppage
of her motion, the Earth should fall into the Sun, as it assuredly
would, the amount of heat generated by the blow would be equal to
that developed by the combustion of 5600 worlds of solid carbon.”

Now, it is supposed by Dr. Croll and others (and here, be it
noticed, we pass to the still less known: to the purely hypothetical,
but still conceivable), that the nebulous mass from which the solar
system has been evolved resulted from the collision in space of two

C. Lloyd Morgan—Physiography. 253

vast masses moving at great velocity. Hach of these masses may
be supposed to have developed from a nebulous mass, in the same
way that the solar system has itself developed. Such nebulous
masses were endowed with that high form of energy, which may be
termed, generally, the energy of separation. But we have seen that
this and all other intermediate forms of energy tend to run down,
and be degraded to heat uniformly distributed throughout space.
Some men of science tell us that this will be the ultimate condition
of the energy of the universe. They tell us that the planets will
fall into the Sun, and that thus the matter of the solar system will
be aggregated into one mass: that this mass coming into collision
with another mass similarly formed will produce the nebulous
spheroid from which another system greater and grander than ours
will be formed: and that so the same thing will go on until all the
matter of the universe is aggregated into one mass, and all the
energy of the universe is converted into uniformly diffused heat.

But here we have transcended the powers of tle human intellect.
We have reached that thin atmosphere in which we can no longer
build. We have traced the chain of causation as far as we are able.
We have reached the Unknowable. When we seek to go further:
when we inquire what is matter, what is force, what is the ether
through which force acts on matter, what is the space in which co-
existences are manifested, and the time in which sequences are
manifested: when we inquire what is consciousness, what is the
thought by which we are able to trace to some extent the chain of
causation, we are met by alternative contradictories. We are in the
presence of the Mystery of Mysteries. Let us humbly, modestly,
truthfully confess our ignorance.

It may, perhaps, be said that there is much in the foregoing pages
that is quite out of place in the Gronogican Macazine—much about
wind and aqueous vapours, the Nebular Hypothesis and the Unknow-
able. But is it out of place? If there be any truth in my opening
paragraph—that just as an artist has now and again to view his
picture from a distance, so does the man of science have from time
to time to take a comprehensive survey of his subject—No. In
any consideration, however imperfect, of the work which Geology
is doing for Modern Philosophy, we must weave that work into the
general picture presented by the study of Nature. This I have
attempted to do. In the first place I have endeavoured to point out
the law of causation ; that all that we see about us has been caused
in some way or other. In most cases, from the nature of the subject,
this law of causation has been illustrated qualitatively: but in the
case of the formation of water-vapour the quantitative truth of the
law has been indicated; and the law of the conservation of energy
briefly alluded to. In the second place I have tried to show, as far
as was possible in the space at my command, how the crust of the Earth
has been built up by the mechanical agency of rivers, forming deltas,

“and the vital agency of simply-constituted creatures. By these two
agencies nearly all the rocks have been formed, with the exception
of salt, and, perhaps, magnesian limestone, which are due to

204 W. Davies—On Saurocephalus.

chemical agency. By the action of earth-heat and other causes,
however, some of these rocks have been so altered that their original
source is scarcely, if at all, recognizable. How this earth-heat has
raised the strata, thus formed beneath the sea, above the waters of
the ocean, has been pointed out; and the action of the sea-waves,
and of rain and rivers in carving out the face of the country,
horizontally and vertically, has been indicated. In tracing the
chain of causation from the well-known to the Unknowable, I have
not followed the example set by Prof. Huxley in the excellent little
book which bears the same title as this article. In these days, how-
ever, when we hear so much of the “ pride of Science,” it is well to
point out that in the study of Nature we reach at last ultimate questions,
with respect to which we must one and all confess with modest
humility that we are and must be ignorant. Finally, in making
each fact the effect of one which had gone before it, in time, and the
cause of one which followed, I have aimed at that organization of
knowledge, without which any number of accumulated facts are but
isolated pieces of general information.

T].—On THE NoMENCLATURE OF SAUROCEPHALUS LANCIFORMIS OF THE
British Cretaceous Deposits: witH Derscriprion oF a NEw
Specrzus (S. Woopwakrvii).

By Witu1am Davis, F.G.S.,
of the British Museum.

(PLATE VIII.)

R. MANTELL, in his classical work, the “ Fossils of the South
Downs,” figured two large compressed and lanciform teeth!
preserved in his collection and obtained from the Chalk at Lewes,
as respectively the teeth, of an unknown fish and of a species
of Squalus. Similar teeth, and from the same collection, were
subsequently figured and described by Prof. Louis Agassiz,’ who,
from external characters chiefly, considered them to have belonged
to a Sphyrenoid fish, and he referred them to an American
species founded by Dr. Harlan upon portions of jaws with teeth
in situ found in a Cretaceous deposit in the State of New Jersey,
but described by him® as remains of a Saurian, and to which he
gave the name of Saurocephalus lanciformis. At the time when
Agassiz referred these teeth to Harlan’s species, and determined
their ichthyic character, he had not seen the American fossils; but
he states that these conclusions were subsequently confirmed by
Prof. Owen’s description and drawings of the microscopic structure,
and of teeth of the natural size of the Saurocephalus lanciformis,
Harl., in his “‘Odontography,” p. 130, pl. 55. But Prof. Owen’s
researches were made upon a genuine tooth of the American fossil
sent to him by Dr. Harlan, and not upon an English specimen.
For some years after the publication of Agassiz’s work the species ,
1 op. cit. pl. 33, figs. 7 and 9.
2 Recherches Poissons Fossiles, tom. v. p. 102, pl. 25, figs. 21—29.
3 Journ. Acad. Nat. Sc., vol. ii. p. 337, pl. xii. figs. 1—6.

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W. Davies—On Saurocephalus. 255

was known only by isolated teeth, which are far from rare in
the Chalk and the so-called Upper Greensand of Cambridge;
specimens also occur, though not so abundantly, in other British
Cretaceous deposits. Ultimately a fine fragment of a lower jaw
came into the possession of the late Dr. Bowerbank; while a
portion of a maxilla was obtained by Mrs. Smith of Tunbridge
Wells, both being from the Chalk of Burham, Kent.

These specimens and some detached teeth in his own collection
were figured by Mr. Dixon ;! who also states that he has “‘a portion
of an upper jaw with two teeth,” in his possession; and following
Agassiz he refers these remains to the Saurocephalus lanciformis,
Harl.

It may be stated here, that all these interesting and instructive
specimens from the respective collections of Dr. Mantell, Dr. Bower-
bank, Mrs. Smith and Mr. Dixon, have been obtained for, and are
now preserved i in the National Collection.

Mr. Dixon also figures? and notes a bony rostrum, which had
been obtained by Sir Philip Grey-Egerton, whose practised eye
recognized it as the consolidated and prolonged przmaxille of the
same species of fish to which the remains under consideration
belong. Very recently, I have seen a paper published in 1857 by
Prof. Leidy, of Philadelphia,’ in which he contends that the teeth
referred by Agassiz to Saurocephalus lanciformis, Harl., do not belong
to the species described by Dr. Harlan under that name, but that
they appertain to a very different fish, and in support of his position
Prof. Leidy re-figures and describes the original specimen upon
which the species was founded. A glance at the figures is sufficient
to show that the remains of the English and American fishes, which
have hitherto been considered as generically and specifically the same,
do in reality belong to two distinct genera. It seems strange that
so important a paper should have been overlooked or been but little
known to English ichthyologists, as in all collections I have seen,
this particular form of tooth and also the rostral bones are invariably
labelled as Saurocephalus lanciformis, Harl. The isolated teeth and
jaws, figured in the respective works of Agassiz and Dixon, Prof.
Leidy refers to a Sphyrenoid fish which he names Protosphyrena
feroz, and he further states, that the rostral bones have no rela-
tion to these jaws and teeth, but pertain to a Xiphioid fish, which
he designates Xiphias Dixoni. It is due to Prof. Leidy to state
that these conclusions were derived from the published figures
alone, and not from a study of the fossils.

With a view of testing these conclusions preparatory to re-
labelling the specimens in the National Collection, I carefully ex-
amined and compared all the English types of the species which
have been figured, not only with each other, but also with many
other specimens, more or less perfect, in the same collection; and I

1 Geol. and Foss. of Sussex, p. 374, plates xxx. fig. 20, 21; xxxi. fig. 12;
xxxiv. fig. 11.

2 op. cit. p. 874, pl. 32%, fig. 1

3 Remarks on Saurocephalus and its Allies, Trans. Am. Phil. Soc. vol. xi. p. 91.

256 W. Davies—On Saurocephalus.

have no hesitation in stating, that the isolated teeth, portions of jaws
and rostral bones do appertain to the same species of fish. The
enamel coating of the crown, and the form and structure of the
rostral teeth, are the same in character as the teeth in the maxilla
and mandible; each has a well-developed, laterally compressed
crown, with long fangs, adapted for insertion in distinct sockets ;
and, moreover, the well-ossified and somewhat massive bones of the
mandible correspond in structure, external -ornamentation, and even
in condition of preservation, with the same elements of the ros-
trum. This conclusion is also supported by the fact that wherever
the isolated teeth are found, there are also found portions, more
or less perfect, of rostra. Associated in the same deposits are
frequently obtained coalesced caudal vertebre similar to, but less
symmetrical, and also shorter, higher and thicker, than the con-
solidated caudal vertebre of the Tetrapterus ‘These vertebre I
have long regarded as belonging to the Saurocephalus lanciformis,
as hitherto understood, and have so named them in the National
Collection. It was a simple deduction, derived from the fact that
a fish armed with such a powerful weapon of offence would have
had, to render that weapon effective, an equally powerful organ
of propulsion through its native element. And such coalesced
vertebrae we find in the tail of Xiphias and other recent fishes. In
the same deposits frequently occur either singly, or in displaced
groups, some long bony and unarticulated fin-rays, which probably
appertain to the same species.

That the teeth, in form and mode of implantation in distinct sockets,
simulate the teeth of a Sphyreenoid fish, is apparent, but no fishes of
this family have the premaxillaries consolidated and prolonged into
a bony rostrum; neither have any of the long-beaked fishes of the
Scomber-Esocide, in which family these remains have latterly been
classed. Again, the pair of backward-pointing teeth of the rostrum,
with the well-developed armature of the maxillaries and dentary _
bones, and also the abrupt termination of the mandibular symphysis,
armed with three strong teeth on either side, two of which are
horizontally directed; preclude these remains from association with
Xiphias, in which genus the jaws are all but edentulous, and the
mandibular symphysis acutely pointed.

Therefore, neither of the generic names proposed by Prof. Leidy
are applicable to these remains, but having included in Protosphyrena
two species that are generically distinct, viz. the species under con-
sideration, and the Saurocephalus striatus, founded by Agassiz upon
mere fragments of two jaws, having respectively five and three
teeth in situ; and these, not being inserted in sockets, are clearly not
referable to Saurocephalus, therefore Leidy’s genus might be re-
tained, provisionally, for the S. striatus of Agassiz. It is thus
evident that the British fossils hitherto referred to Saurocephalus
lanciformis are types of a new genus.

Prof. Cope, in 1872, founded his genus Erisichthe upon some
remains found in a Cretaceous deposit in Kansas; these he sub-
sequently figured in his larger work on the ‘Cretaceous Vertebrata

W. Davies—On Saurocephalus. 207

of the West.”! They consist of a maxillary, supposed premaxillaries,
and the anterior portion of a left mandible; and so alike are the
maxillary and mandible to the specimens figured by Dixon that
there could be no doubt as to their being generically the same if we
could assume that Cope had erroneously determined the bones he
refers to the premaxillaries; but if he is right, they cannot be cor-
related, for in the American species the premaxille are not prolonged
into a bony rostrum, a feature not mentioned by him as characteristic
of this, or even of any other species described in the above-
mentioned work. Yet it would seem as though he had a doubt as
to the correctness of his interpretation of these bones, for he does
‘ not refer to them in his diagnosis of the genus nor in his description
of the species. The maxillary bones, he states, ‘are sub-triangular
in form, and support three or four large lancet-shaped teeth at the
middle of their length. There are no teeth beyond them; but, on
the deeper side, there are several small lancet-shaped teeth.” ?

The maxillary figured in Dixon, but of which no description is
given, is also sub-triangular in form, but much deeper in proportion
to its length than the Hrisichthe nitida, Cope; the surface having an
irrecular rugose ornamentation. It shows a continuous series of
seven lanciform and equidistant teeth, increasing in size from the
anterior tooth to the fourth; this, and the posterior teeth, appear
from the alveoli to have been of uniform size. ‘Three teeth are in
situ, viz. the first, or anterior, the fourth and sixth, the others being
represented by the alveoli alone. More or less deeply seated in each
of these are the apices of successional teeth. It also differs from
E. nitida, insomuch that it has no outer row of small lancet-shaped
teeth. The anterior termination of the bone is wanting; it measures
in length three and a half inches, and one inch and a half at the
deepest part between the sixth and seventh alveoli, the pre-
maxillary sutural margin being entire.

The anterior portions of the mandibular rami, having regard to
specific differences, are so alike in the respective drawings of Cope
and Dixon, that they might be assigned without a doubt to the same
genus, were it not for the other fragments which are referred to it by
Cope. His description of this bone is as follows :—

“The teeth on the greater part of the dentary are intermediate in
size between the large and small ones of the maxillaries; they stand
on the outer edge of a broad horizontal alveolar plane. There are
three large teeth in a series at the end of the dentary on the outer
side; they have been lost, but their bases are broader ovals than
those of the maxillary bone. On the middle line of this part of the
dentary is a close series of small compressed teeth with striate enamel,
standing on a ridge of the bone; they leave the last large tooth to
the outer side, while on the inner side stand two or three lancet-
shaped tusks of a short row further back.”—op. cit., p. 218.

The characters of the specimen from Kent are thus defined in
Dixon’s work :— :

1 Report of the United States Geological Survey of the Territories, vol. ii. 1875.
2 op. cit. p. 218.

DECADE II.—VOL, V.— NO. VI. 17

258 W. Davies—On Saurocephalus.

“The finest specimen of this species hitherto discovered belongs
to Mr. Bowerbank ; it shows the extremities of the two rami of the
lower jaw; the dentary bones thicken out as they converge to the
symphysis to give space for the implantation of six large lanciform
teeth, which project forwards nearly in a horizontal direction; the
dentary bone immediately behind the symphysis is armed on its”
inner edge with strong laniary teeth; the two hinder ones being on
either side considerably larger than those that precede them; the
specimen is broken off a short distance from the commencement of
the outer row, the anterior teeth of which are small.’’!

We have here many essential points in which the two specimens
agree, the main points of difference being the anterior row of small
lancet-shaped teeth upon the outer border of the dentary bone in the
American species, but which are not present in the British specimen,
which has the anterior teeth of the dentary bone in one continuous
series, with smaller teeth in advance of the larger; the small teeth
of the outer border commence about half an inch behind the last
laniary tooth of the inner border.

To the above description may be added the satisfactory evidence of
the mode of succession of the teeth. This is shown by the bases of
the first laniaries, as also those of the upper and horizontal teeth of
the symphysis on either ramus of the mandible having been absorbed
to make room for the successional teeth, the apices of which are
present in each alveolus excepting that of the right laniary, which
has been lost; they abut against the absorbed portions of the fangs,
and are thus developed, as in Mosasaurus and other Lacertians, on
the outside, and not within the pulp cavity of the mature tooth.

I had written the foregoing remarks, when my friend Mr. HE. T.
Newton, F.G.S., of the Jermyn Street Museum, to whom I had shown
a portion of the manuscript, very kindly called my attention to a paper
“On the genus Hrisichthe,’ published in 1877, in the sixth Bulletin
of the U.S. Geological and Geographical Survey, a copy of which he
had received from Prof. Cope; and I publish them as an instance of
not uncommon occurrence, of an independent conclusion derived from
an actual study of special objects, in some degree confirming what
had already been accomplished by other investigators.

In this paper Prof. Cope has identified and described three species
of Erisichthe from Kansas, and concludes with the following para-
graph: ‘A fourth species has been found in England, and figured by
Dixon in the ‘Geology of Sussex.’ The portions represented in this
work are the mandibles, which resemble those of EH. nitida, and which
were supposed at that time to belong to a species of Sawrocephalus.
A muzzle, perhaps of the same species, was regarded as a Sword-fish,
which was called Xiphias Dixonw by Agassiz.” This is an error; the
name, as we have seen, was given by Leidy. He continues, “It
should be now termed Hrisichthe Diaoni.”

With regard to the genus, he remarks that “ Hrisichthe nitida, Cope,
was originally represented by a few portions of the skull; among
other pieces, the premaxillary and dentary bones being present. The

1 Dixon, Geol. Suss. pp. 374, 376.

W. Davies—On Saurocephalus. 209

latter element was correctly determined, but the premaxillary was
called maxillary in my description.” Having obtained another
specimen from Kansas, he continues, ‘‘ From this and other specimens
I discover that the anterior portion of the skull, probably the ethmoid
bone, is produced in a long beak, in general form similar to the
sword-like snout of the Sword-fishes of modern seas.” The pro-
longation of the ethmoid into a long snout is an important discovery,
as it clears the difficulty in regard to the bones previously referred
to the premaxillaries. He continues, ‘‘The specimen above mentioned
includes also the maxillary bones, so that their true character is now
clear. A remarkable feature of the genus is displayed in the man-
dibles. Each of these is compound in the region usually composed
of the simple dentary bone. It there consists of three parallel
elements, an internal and an external embracing a median element.
The inner bears a band of teeth en brosse on its inner and superior
aspect, and the external a few teeth of similar character, on its
superior edge. The large lancet-shaped teeth are borne by the
middle element, excepting some of the largest near the symphysis.
Two of these on the inner side of the ramus originate in the internal
bone.”

The mandible figured by Dixon has but two parallel elements in
each ramus, and bears no inner “band of teeth en brosse on its inner
and superior aspect ;” proving that the number of the elements in
the region of the dentary bone is only of specific and not of generic
value. Other points of specific differences in the respective mandibles
J have previously mentioned. Prof. Cope further states that, ‘‘ ante-
rior to the premaxillary bones, on the inferior aspect of the ? ethmoid,
is situated a pair of large, compressed, double-edged teeth, whose
alveoli are close together. Only one of these teeth is in functional
service at a time.” Here again, supposing this to prove a constant
character in the American fossils, the species of the two countries are
not in harmony; for in Mr. Dixon’s collection is a proximal portion
of a rostrum, referred by him to the upper jaw, in which both teeth
are preserved intact; they are nearly equal in size and fully developed
(Plate VIII. Fig. 3) ; and in another specimen in the British Museum,
although the crowns are broken, and one tooth is larger than the
other, yet they demonstrate clearly that they were both sufficiently
projected beyond their respective alveoli as to have been in func-
tional service together. In other imperfect examples in the same
collection, the fangs show that the lost crowns of the teeth must
have been well if not equally developed. And in all, one tooth, the
largest, is slightly in advance of the other. The rostra are hollow for
a large portion of their length.

Prof. Cope, to whom we are largely indebted for his original
investigations on the Cretaceous fossil fishes, refers Hrisichthe to his
family Saurodontide, in which group of fishes, species of most of
the genera are to be met with in the Cretaceous formations of
England.

Saurocephalus lanciformis will, therefore, excepting as a synonym,
have to be excluded from the catalogue of British fossils, and the

260 | W. Davies—On Saurocephalus.

remains which have hitherto borne the name will henceforth appear
in the corrected lists thus :
Erisichthe Dixoni, Cope (sine descrip.); Bull. of the U.S. Geol. and Geog. Sury.,
vol. ili. 1877, p. 821.
Saurocephalus lanciformis, Harl.; Agassiz, Rech. Poiss. Foss., tom. v. pt. 1, p.
102, pl. 25c. figs. 21-29. Dixon, Geol. Suss., 1850, p. 374, pl. 30, figs.
21, 21a-d. pl. 31, fig. 12, pl. 32%, fig. 1, pl. 34, fig. 11.
Protosphyrena ferox, Leidy, in part (sine descrip.) ; Trans. Amer. Phil. Soc.,
1857, vol. xi. p. 18.
Xiphias Dixoni, Leidy, in part (sine descrip.), op. cit.

All the European species referred to Saurocephalus by continental
authors having been founded upon isolated teeth, similar in character
to those erroneously referred to the genus by Agassiz, will have to
be transferred to Erisichthe or some allied fishes. Nevertheless,
there is evidence that Saurocephalus is a European genus; for among
the fossil fishes from the Upper Cretaceous beds of Maestricht, in the
Van Breda collection in the British Museum, are remains of an un-
described species. They are contained in a split block of the well-
known friable matrix, which expose on their opposing surfaces the
greater portion of a ramus of a mandible with teeth. Since its
acquisition by the British Museum, a maxillary and some bones of
the head which were present in the matrix have been developed,
but unfortunately the bones are in too fragmentary a condition to
be satisfactorily determined. The maxilla is also imperfect, and is
so placed that the form and dimensions of so much as is preserved
cannot be ascertained, for the anterior end underlies the dentary
bone, at right angles and in immediate contact with it; the upper
sutural margin also, if present, is imbedded in the matrix among
the crushed bones of the head, but fortunately, as regards the satis-
factory determination of the genus, it shows the inner and most
important view. The length of the alveolar border as seen is 24
inches, and the greatest vertical depth of the bone exposed is 7
lines. It contains twenty teeth, the crowns of some are broken, but
those of the first eight are entire, and some are represented by the
apices of successional teeth just emerging above the margins of their
respective alveoli. The teeth are closely set, having comparatively
short depressed crowns with long bases. ‘The inner side of the
alveolar border is slightly depressed to a vertical depth of about one
line; about midway along this depression, and opposite to the
vertical axis of the teeth, commences a series of short oblique notches,
which terminate in foramina upon the raised portion of the bone.
These foramina are, according to Leidy, characteristic of the genus,
their function being the nutrition of the successional teeth. It
differs from the maxillaries figured by the same author in being
intermediate in size between Saurocephalus lanciformis and S.
Leanus; the apices of the teeth are also longer in proportion to their
breadth than in S. lanciformis, and this last species does not appear
to have any foraminai notches ; those in S. Leanus are straight, and
have their origin at the alveolar margin; whilst in our specimen
they are oblique, and commence about midway from the margin.

In splitting the block the dentary bone was unfortunately divided,

W. Davies—On Saurocephalus. 261

portions adhering to each counterpart. It is imperfect, insomuch as
neither the symphysis nor the articular bone are complete; the
angular bone is also imperfect, and the lower marginal border is not
clearly defined: yet enough is preserved to enable us to form an
approximate estimate as to its original size and form. The fragment
is 6 inches and 2 lines in length, of which, about 44 inches was
occupied by the dental alveoli; at a distance of 4 inches from the
symphysis it has a vertical depth of 2 inches and 4 lines, and from
this point it tapers to a depth of only 10 lines at the symphysis.
Upon one block, and occupying a space of 1 inch and 8 lines of the
posterior half of the dentary margin, are preserved a consecutive
series of 17 entire teeth, one just emerging from its alveolus; they
are closely set, and gradually increase in size from the front to the
back, the anterior tooth being 4 lines high, and the last having a
height. of 6 lines, the crown being 24 lines high, and in antero-
posterior breadth 1 line at its base; these dimensions seem to be
about the relative proportions of the crown to the fang in all the
teeth; they are compressed and lancet-shaped, and the enamel is
very finely striated. Hach fang has a central shallow vertical sulcus,
which is continued into the base of the crown, but they are not so
distinctly facetted at the sides as are the teeth of Saurocephalus lanci-
formis. Anterior to, and also behind this series of teeth, the alveolar
region of the dentary is broken, so that we cannot with certainty
estimate the number of teeth the mandible contained.

Upon the counterblock are preserved the imperfect angular bone
and the symphysial end of the mandible, which supports the first
five teeth; they are separated by a considerable interval of the
broken alveolar border trom the other series; these anterior teeth
are much smaller, the fifth, or last tooth, which is wholly exposed,
being but 2 lines in height. They thus agree in their relative
proportions with regard to the gradual increase in size of the teeth
from the front to the back of the mouth. The mandible is deep and
laterally compressed, the bones being very thin; the articular bone
is comparatively short, but its sutural margins are obscure; it shows
the articular notch. A portion of a quadrate bone is present, of
which, little more than the articulating condyle is preserved.

The bones of the head, as previously stated, are too fragmentary
and displaced for their characters to be accurately defined.

It is with much pleasure that I dedicate this new species to my
friend,’ Dr. H. Woodward, F.R.S., etc., by whose exertions this
specimen, with many other fine fossils from the Maestricht beds
forming the Van Breda Museum at Haarlem, were secured for the
National Collection.

Fie. EXPLANATION OF PLATE VIII.

1. Inner view of the maxillary of Sawrocephaius Woodwardi, showing the foramina
and notches, natural size.

2. Outer view of the left mandibular ramus of the same, drawn from the two blocks
of matrix, natural size. é

2a. Enlarged outer view of the anterior tooth of the posterior series, 3 times nat. size.

2). Inner view of the same tooth.

3. Proximal end of muzzle of Erisichthe Dixoni, showing the pair of rostral teeth.

262 Rev. E. Hill—On Changes in the Earth’s Avis.

JII.—On tHe Possiprtity or CHancEs IN THE Hartu’s AXIs.

By Rev. E. Hitt, M.A., F.G.S.
Fellow and Tutor of St. John’s College, Cambridge.

Miao possibility of change in the position of the Earth’s axis
seems periodically to attract attention. This is happening now.
Professor Haughton has written upon this subject, Sir William Thom-
son has alluded to it, while two important papers have been read
upon it, one by Professor Twisden before the Geological Society, the
other by Mr. George H. Darwin before the Royal Society. This
article is an endeavour to exhibit to the general reader the assump-
tions with which they have started, and the results they have ob-
tained.

The phrase ‘‘change in the Harth’s axis” is susceptible of several °
meanings which do not coincide in like changes of climate. The
Earth may be supposed to be tilted, so that its axis of rotation
should make a new angle with the plane of the ecliptic. Or the
Earth may retain the same shape, but be caused to rotate about an
axis holding a different position in its body. Or—the change most
easily conceived by a geologist—the shape may be supposed to
change by expansions and contractions, so that the axis of figure
shall occupy a new position in the body of the earth, which how-
ever shall continue to rotate about an axis the same in direction as
before. Or lastly, the shape may thus change, and the axis of rota-
tion change also. They are however to separate in their change,
for if they kept together this case would agree with the: first men-
tioned. Imagine the Harth a huge orange, spinning, impaled by
some giant of Hindoo mythology on a correspondingly gigantic
knitting needle. The first change would be produced by his tilting
the needle, the second by impaling the orange differently, the third
by squeezing it into a new shape, while the fourth would naturally
result from the difficulty of holding the needle steady during this
operation.

There are two kinds of alteration of climates which can thus be
produced on the Earth. If the axis of rotation were tilted (as in
the first case), all places would have the same latitude as they now
have, all places on the same latitude would receive heat and. light
alike, but they would not receive these in the same way as they do
now. ‘The lengths of the seasons, and the Sun’s midsummer and
midwinter altitudes, would be changed. The Arctic Circles and the
Torrid Zone would change their breadths. An alteration of climates
would result, and the alteration would be of like nature on all sides
of the Pole. What that alteration would be is not so easy to say.
Probably a tilt making the axis more nearly perpendicular to the
plane of the Ecliptic would render the Polar climate milder. This
would agree with the supposed condition of the Miocene age. But
it will be seen hereafter that this change is exceedingly difficult to
produce. .

The other kind of alteration would result were the axis of rotation to
retain its present direction in space but to occupy a different position in

Rev. E. Hill—On Changes in the Earth's Avis. 263

the body. The orange would be impaled differently on the knitting
needle. The Poles would not be at the spots where they now are.
The parallels of latitude would lie on different circles, for latitude
depends on distance from the pole of rotation. The light and heat
received by all places on the same latitude would be equal, and as
much as that latitude now receives, but any one place would not
receive the same as before. The latitudes of places would be changed.
There would be as hot a Torrid Zone, but it would occupy a different
belt of the surface. There would be as wide an Arctic Circle, but its
centre would be at another spot. The changes in climate would not
in this case be the same on all sides of the Pole. On the side nearer
the new Pole they would be made more arctic, more temperate on
the side remote. Had the Pole been thus shifted in a past age, traces
should somewhere remain of the then ice-cap. Geologists however
say that at present none are known.

Professor Evans, in his presidential address to the Geological
Society, asked mathematicians whether the elevation of a certain
belt of land would not carry the Harth’s axis of figure 15° or 20°
away from its present position, and whether ultimately the axis of
rotation would not again coincide with the axis of figure. That is,
he supposes the earth deformed, and asks whether this will not
cause such a change in the rotation axis as will end ina tilt of the
earth as final result.

Professor Twisden’s paper, printed in the last number (133) of
the Quart. Journ. of the Geol. Soc., answers this question. He takes
Professor Evans’ supposition of an elevated zone of land, and calcu-
lates the deformation to which it is equivalent. He shows that
instead of shifting the axis of figure 15° or 20° from its present
position, it would produce only about 10’ of angular displacement,
and that to obtain so great a change as even one degree, the zone of
land must be elevated no less than five miles. He then discusses
what would result from a separation between the axis of figure and
rotation. He points out a startling consequence, namely, that two
vast tide-waves would sweep the earth, submerging the Equator
every 150 days to a depth of six miles or more. He adds some
interesting remarks on the tendencies to alteration which the present
river-systems may be producing, pointing out that not only are their
effects extremely minute, but that many of them tend to compensate
for each other.

The condition necessary to produce Professor Twisden’s tide-
waves is that the Harth’s axis of figure should occupy a position
different from that of her axis of rotation. Now expansion and
contraction, upheaval and depression, denudation and deposition,
must necessarily deform the Earth and displace her axis of figure.
But this alteration will be produced gradually. What will happen
meanwhile to the axis of rotation? Can it be supposed to remain
unchanged ? To this question an answer is provided by Mr.
Darwin’s paper.

The conclusions of this paper are reached by rather complicated
analysis. A simpler process suggested by Sir William Thomson is

264 Rev. E. Hill—On Changes in the Earth’s Axis.

given in an appendix. The main results may be obtained by general
reasoning without symbols. But in every case a considerable know-
ledge of Rigid Dynamics is required; so the non-mathematical reader
must, I fear, take the statements on trust. Mr. Darwin considers the
case of the earth undergoing a very slow and small deformation ;
slow, so that thousands of years are required for the change, and
small, so that the change when made shall not have greatly altered
the shape. This will shift the axis of figure away from that original
position in which it coincided with the axis of rotation. But move-
ments will thus be set up in the Harth such that coincidence will be
periodically regained. And the separation between the Poles will
be at all times so exceedingly small that for all practical purposes
they are coincident. In fact, the distance between the Poles cannot
ever exceed about one-third the distance over which the pole of figure
would be shifted by these deformations in a period of 300 days. Now
this, with such elevations as we at present know, of a few feet in a
century or the like, would be a quantity almost microscopic. Thus
Professor Twisden’s tide-waves cannot arise, since the change required
to produce them cannot come into existence.

Having thus settled that the two axes keep together in the body,
the next question to be considered is their position in space. Is it
altered or not? Do the coincidence-restoring movements bring back
the axis of figure to the position in space from which it started, or
does the rotation-pole follow the figure-pole in its wanderings? Is
the Earth not tilted or tilted? Is not or is the obliquity changed ?
The calculations show that it is not to any perceptible degree. For
instance, the process of production of an ice-cap reaching down to _
lat. 45° would not alter the obliquity by -0005 of one second. Hence
the deformation will produce a change equivalent to the second case :
the orange impaled on the needle differently. It will bring other
parts of the Earth into the Arctic regions, while the axis of rotation
retains a practically unchanged position in space. The alteration in
climate would be of the second kind, one whose evidence might be
expected to include some traces of the former ice-cap.

Having thus worked out the effects of Deformation, Mr. Darwin
calculates how much deformation can be produced by any conceivable
elevation of land. He investigates very skilfully the shapes and
positions of regions of upheaval and subsidence which would be most
effective for change. He takes the case of an ocean bed 15000 feet
deep elevated into a continent 1100 feet high (which is a little above
the average), and obtains the new positions of the axis of figure
corresponding to various assumed areas of such elevation and like
depression of the surface. The possible alteration of position is not
great. A continent equal to Africa elevated, and an equal area de-
pressed in the most effective shapes and positions, would produce a
change in the position of the Pole of less than two degrees. More-
over, this is obtained on the supposition that the elevation and de-
pression are obtained by the actual removal of matter from the surface
of the one area, and its deposition on the other. If we adopt the
easier supposition that elevation is produced by the expansion of sub-

Rev. E. Hill—On Changes in the Earth’s Axis. 265

jacent strata, depression by their contraction, the resulting change is
diminished to a considerable, possibly to a very great extent. If, for
instance, the expansion or contraction take place between the depths
of 10 and 50 miles, the shift of the Pole will be diminished to less
than a sixtieth part of its former amount. If the supposed areas
occupy positions other than the most effective, these changes must
be still further reduced, and may even vanish altogether.

These calculations are based on the supposition of a practically
rigid Earth. If its interior be fluid, Professor T'wisden’s tide-waves
still hold good, for their magnitude depends only on observed
quantities. Mr. Darwin’s calculations involve Laplace’s hypothetical
law of density, and obtain results true for a solid globe. But mathe-
maticians seem to consider that even if the interior be fluid, yet as
far as change of rotation is concerned, it must behave as if it were
rigid. Accordingly the results are unaltered.

Mr. Darwin points out that if alterations in the Harth’s surface
should produce a separation, however small, between the axes of
figure and of rotation, the mass of the Harth would be thrown into
a state of stress, which he suggests might be relieved by an earth-
quake restoring coincidence. Though the strains would be extremely
minute, this seems possible. He works out the results of this, and
also those of the Harth being plastic, capable of yielding to any
stress, and deduces that the pole of rotation would describe a kind
of spiral round the point towards which the pole of figure was being
shifted by the change. This point he had shown could not be far
distant, and therefore the spiral could not be wide. Nevertheless
he seems to think that in a plastic globe this cause might lead to
considerable wandering of the poles. But with respect to the Earth,
he appeals to Sir William Thomson’s demonstrations of its rigidity
as excluding the hypothesis of plasticity.

Mathematicians may seem to Geologists almost churlish in this un-
willingness to admit a change in the Harth’s axis. Geologists scarcely
know how much is involved in what they ask. They do not seem
to realize the vastness of the Earth’s size, or the enormous quantity
of her motion. When a mass of matter is in rotation about an axis,
it cannot be made to rotate about a new one except by external
force. Internal changes cannot alter the axis, only the distribution
of the matter and motion about it. If the mass began to revolve
about a new axis, every particle would begin to move in a new
direction. What is there to cause this? When a cannon ball strikes
an iron plate obliquely, the shock may deflect it into a new direction.
The Harth’s equator is moving faster than a cannon ball. Where is
the force that could deflect every portion of it and every particle of
the Earth into new directions of motion? The-cannon ball is
slightly and slowly deflected by gravity. But the attraction of the
Sun and Moon could produce on a slightly distorted globe no effect
essentially different from what they produce now.' No other force
exists capable of producing any effects at all.

1 Suppose the Sun’s attraction at any instant to be causing in the Karth a be-
ginning of a rotation about any diameter through the Equator. Twelve hours later

266 A. J. Tukes-Browne—The Formation Of © Ll?

Even if geologists will give up asking for a tilt of the axis, and
be content with a new shape, still the mathematician asks whether
they have realized the Harth’s size. ‘Its deviation from a sphere is
trifling in amount.’ In what amount? In figure doubtless. Were
its section drawn on this page a microscope would be wanted to
distinguish the curve from acircle. But in quantity the deviation is
not trifling. The height of the highest mountain and the depth of
the deepest sea together do not equal its extent. All the mountain
chains added together would not perceptibly increase the volume of
the equatorial protuberance. The mass of all the continents re-
inforced by that of all the seas would not be the fifth part of it.
To change the Earth’s shape this vast protuberance must be shifted
or masked. Where is the power that can shift it, the elevation that
can mask it? What are our puny upheavals and subsidences of an
ocean here and a continent there compared with a girdle of matter
thirteen miles in thickness? Take an extreme supposition. Remove
10,000 feet of rock from the surface of one-half the Harth and
spread it over the other half. You could not thereby bring the pole
half way to the present Arctic circle. Sufficient changes in the
Harth’s surface will undoubtedly shift the pole. But will geologists
grant the changes that would be sufficient ?

IV.—Tue Formarion oF Trtt.
By A. J. Juxes-Browne, B.A., F.G.S.

ATOTWITHSTANDING the numerous papers which have lately

been written on the subject of glacial deposits, there is one
question of fact which does not appear to have been satisfactorily de-
cided. I refer to the formation of Till underneath glaciers, concern-
ing the possibility of which somewhat different statements were put
forward by two writers in the February Number of the GEoLocicaL
Magazine.

The following passage occurs in Dr. James Geikie’s paper on the
Preservation of Deposits under Till :—‘“ It is needless to refer one to
the petty glaciers of the Alps and Norway to prove that glacier-ice
cannot both erode its bed and accumulate débris upon that bed at one
and the same time..... No considerable deposit could possibly
gather below alpine glaciers like those of Switzerland and Norway ;
but underneath glaciers of the kind that invaded the low grounds
of Piedmont and Lombardy we know that thick deposits of tough
Boulder-clay, crammed with scratched stones, did accumulate.”

At a later page of the same Number Mr. G. Linnarsson animad-
verts upon a portion of Prof. Milne’s “ Travelling Notes,” which have
recently appeared in this Macaztng, and says—‘‘ That, actually, Tul
this diameter will have turned with the Earth’s diurnal motion so as to lie in the
same line but reversed. The rotation produced at the former line will be in the
opposite direction to that now being caused, and will be neutralized by it. The
afternoon will undo the morning’s work. This explanation is very insufficient, giving
no account of Precession, but it may assist those unacquainted with Rigid Dynamics
in comprehending how the Sun may be perpetually drawing the Earth’s equator
towards coincidence with the Ecliptic, yet never bringing it any nearer.

A. J. Jukes-Browne—The Formation of ‘ Till.’ 267

is formed, and rocks polished and striated by glacier-ice, is so well
known from observations in the Alps and elsewhere, that I think
Prof. Milne himself cannot deny its capability of producing such
effects.” The italics are mine.

Prof. Milne will doubtless state his own views more fully, and I
think he may very fairly claim to have the evidence of Till being
formed under Alpine glaciers set before the readers of this Macazinz.

In Dr. Geikie’s ‘‘ Great Ice Age,” I only find mention of the stones
frozen into the bottom of glacier-ice (p. 40), and a theoretical descrip-
tion of the supposed formation of ground-moraine under the Scottish
ice-sheet (p. 68). I think, therefore, that many geologists would be
glad to have an authentic description of the actual formation of
moraine profonde at the present day, either in Switzerland, Norway or
Greenland. Have the original statements of Agassiz and Charpen-
tier ever been confirmed, and are the facts such as would warrant
the creation of such a monster as modern glacialists have constructed
out of their moraine profonde ?

One good observer at any rate replies in the negative; speaking
of some retreating Swiss glaciers, Prof. Bonney says,’ “In no case
have I been able to find any deposit resembling Till or Boulder-
clay; .... by availing myself of crevasses, etc., ] have made my
way occasionally for some little distance beneath the ice. Nothing
has been seen but bare rock with now and then a film of mud ora
passing stone.”

Dr. Geikie, however, is quite satisfied that no considerable deposit
accumulates under Alpine glaciers, and he says, ‘‘ A mountain glacier
is one thing—a glacier extending far into the low grounds beyond
the mountains. . . . is another and very different thing.” But is
the difference more than one of degree? their behaviour, ceteris
paribus, must surely be the same. Dr. Geikie maintains that the
moraine profonde will only be formed in any quantity when the
glacier reaches the plains beyond the mountains, but the upholders
of the glacier erosion theory say that a lake is likely to be formed
where a glacier debouches on to level ground. Dr. Geikie has,
of course, thought over this difficulty, and can doubtless explain
how he reconciles the two views, if indeed he accepts the latter.

Again, the Greenland glaciers are of large size, but can he point to
the existence of griind-moraine beneath them? Those descriptions
of Greenland ice which I have had an opportunity of reading seem
rather to negative than confirm the supposition of its existence. An
excellent account was contributed to this Magazinn® by Professor
Nordenskiold, who distinctly says that when the ice retires it gives
rise to a slope covered with boulders, not to a moraine. Again he
speaks of the smoothed, scratched and grooved rocks, showing that
the fiords have been widened and cleansed from earth, gravel-beds
and mountain detritus by the operation of glaciers (loc. cit. p. 365).

There are, however, two peculiar features which are observable
along the coast, and have been described by most travellers in

1 Grotocicat Macazing, Dee. II. Vol. III. p. 197.
2 GrotocicaL MacazineE for 1871, Vol. IX.

268 A. J. Jukes-Browne—The Formation of ‘ Till”

these regions. The first of these is the strip of border-land which
intervenes between the inland ice and the sea-margin, and which is
the habitable part of the country; over its surface are scattered
occasional ponds and lakelets, it is clothed in summer time with a
certain amount of vegetation, and is frequented by many Arctic
animals. The second feature consists in the frequent occurrence of
clay banks along the shore, and especially in front of some of the
larger glaciers. Now have we not in these phenomena some indi-
cation of the conditions under which the so-called interglacial beds
and the so-called Till were severally formed ?

Prof. Nordenskiold (p. 409) describes a raised plateau of marine
glacial clay, now forming part of this border-land, and covered with
a scanty vegetation ; suppose this land surface to be gradually sub-
merged again, so that the sea might once more wash against the
face of the inland ice, what succession of deposits should we then
expect to be produced? would not the land-surface with its oc-
casional fresh-water beds be covered by more or less stratified
marine deposits passing up into unfossiliferous glacial clay, in which
erratics would be rare or frequent according to the production of
icebergs from the ice-wall? and would not the whole series be very
similar to that near Woodhill Quarry in Ayrshire, as described by
Dr. Geikie at pp. 160-2 of his “Great Ice Age”? The succession of
changes which he considers to be indicated by the evidence there
found are given at p. 174, and these are exactly what we have just
supposed as taking place in Greenland, only that the periods of time
would be comparatively short, the changes of climate less extreme,
and the upper glacial clay would not be a moraine profonde.

In a note at p. 185 concerning the similar succession of beds in
Lewis, Dr. Geikie says:—‘“I thought the beds between the two
Tills or Boulder-clays might indicate merely a temporary retreat of
the ice during some exceptionally mild years, but subsequent and
more detailed observations in the island have satisfied me that the
appearances presented by the Drift cannot be thus explained.” I
think I am not the only reader of this MaGazinE who would wish to
be similarly satisfied. The members of the Scottish Survey are, I
believe, unanimous in accepting the moraine profonde theory ; those
of the English Survey, who are now mapping the Drifts of Hast
Anglia, are mostly inclined to the hypothesis of the marine or sub-
littoral formation of Boulder-clay.

It is worthy of note that these two theories lead to entirely
opposite conclusions regarding the periods of elevation and sub-
mergence. According to one set of observers the land is high and
elevated at the very same time when the others believe it to have
been low or submerged.

Must we ever thus agree to differ, and is there no possibility of a
middle course being found, in which we may sail safely between the
dangers of icebergs on the one hand and ground moraines on the
other? I for one am quite willing to be partially if not entirely
converted, but I am still in the sea of difficulties.

If Dr. Geikie favours me with any reply to the above remarks,

R. Etheridge, Jun.—Paleontological Notes. 269

will he be good enough to say whether he conceives the moraine
profonde was or was not frozen into the base of the ice, and if so
frozen as to move with it, what caused the moraine to be separated
and left behind at any point during its descent.

V.—PatmontrotoeicaLn NorTeEs.
By R. Eruezriner, jun., F.G.S.
(Continued from p. 119.)

1. ARBUSCULITES ARGENTEA, P. Murray (Hdinb. N. Phil. Journ.
1831, vol. xi. p. 147).—Under the title, “Account of the Arbus-
culites argentea, from the Carboniferous Limestone of Inverteil,
near to Kirkcaldy, in Fifeshire,” a curious paper was published in
1831, by Dr. P. Murray, of Scarborough. The organisms are
described as “very delicate vermiform bodies, in fragments of
different lengths, shining with metallic lustre, neither articulated
nor cellular, and resembling broken bits of silver wire.” The
author adds, ‘‘It would appear to have been an attached Mollusc,
dichotomous at first, but afterwards sending out lateral branches,
moderately tapering, and with very distant and obscure (if any)
articulations, grooved longitudinally, and composed of a bright
silvery cortical case, and a solid axis of carbonate of lime... . It
differs decidedly from the Crinoidal animals, which are regularly
articulated; and varies nearly in the same degree from the Coral-
lines, etc., by not displaying the cellular structure characteristic of
that family.” Dr. Murray ultimately places this fossil amongst the
Corallines, selecting for it a provisional resting-place in the third
order of the first class of Lamouroux.

Amongst the many fossils I have seen from Inverteil I have never
been able to recognize any body which would answer to Dr. Murray’s
description and figure of Arbusculites argentea, and, so far as I am
aware, it has been entirely lost sight of by all subsequent writers.
I shall be glad if any of my fellow-workers in Carboniferous Paleon-
tology, by a study of the original article, can throw any light upon
this obscure fossil. According to Dr. Murray’s description, the
want of articulations and dichotomous nature separate it from the
Crinoidea. It may be some form of Polyzoa, but the absence of
cells renders it doubtful. The figure given by Dr. Murray at once
shows that the fossil cannot be the tubes of Annelida. The descrip-
tion, ‘resembling broken bits of silver wire,” accords better, so
far as my knowledge of Carboniferous organisms goes, with the
long spines of Producti; but in this reference we are again con-
fronted with the dichotomous nature of the fragments.

2. IcntTHyoLiTHUS CLAcKmANNENSIS, Fleming (Hdinb. N. Phil.
Journ. 1853, vol. xix. p. 314, t. 4).—The fact that Prof. Fleming ~
was one of the earliest observers, although apparently subsequent
to Agassiz, to describe the well-known Carboniferous fish Mega-
lichthys Hibberti, appears to have been generally overlooked. His
paper, “Notice of the Remains of a Fish found connected with
a Bed of Coal at Clackmannan,” and published in 1835, makes it
quite clear that Dr. Fleming was perfectly well acquainted with this
fish under the above name, obtained “in the course of the mining

270 LR. Etheridge, Jun.— Paleontological Notes.

operations of the Devon Iron Company, and in the neighbourhood
of their works.” The specimen consisted of a portion of an indi-
vidual exhibiting both sides of the body, with a large number
of scales in position, which were recognized by Dr. Fleming as
“the scales of a fish.” The specimen, when slit horizontally,
exhibited the remains of the vertebral column. Upon my calling
the attention of Dr. R. H. Traquair to this paper, he at once
recognized in the figures an unlabelled specimen of M. Hibberti in
the Museum of Science and Art, Edinburgh, but which he had
long surmised formed a portion of the ‘“ Fleming Collection,” de-
posited in that institution. The genus Megalichthys had been
established previously by Prof. Agassiz (Brit. Assoc. Report for 1884,
p- 448), and the species M. Hibberti indicated in a foot-note attached
to the paper in question, ‘‘On the Fossil Fishes of Scotland.”

3. CorBULA Limosa, Fleming (Brit. Animals, 1828, p. 426).—The
type specimens of this species are preserved in the “ Fleming
Collection,” Museum of Science and Art, Edinburgh, and are from
‘‘slate-clay connected with Carboniferous Limestone.” ©. laminosa
appears to have been entirely lost sight of by subsequent writers,
except Prof. Morris (Cat. Brit. Foss., second ed. 1854, p. 195). I
am at present in doubt as to the true generic relations of the species,
but it is not unlikely that it may prove to be a Schizodus, or closely
allied genus. It has the anteriorly incurved beaks of the former.

4, Venerupis Lyrti, Fleming (MS.).—There is also in the
above collection a very fine Carboniferous bivalve bearing a label
with the above name. So far as I know, Prof. Fleming did not
publish a description of it, and I do not find it mentioned in any
list. It is a large Edmondiform shell, apparently near Edmondia
rudis, M‘Coy; EH. gibbosa, M‘Coy; E. quadrata, M‘Coy, or E.
oblonga, M‘Coy. I hope to describe it fully.

5. PLEUROTOMARIA HUMILIS, de Koninck (Foss. Pal. Nouv. Galles
du Sud, 1877, pt. 3, p. 325, t. 28, f. 14).—A new form of Pleuro-
tomaria was shown me by Mr. John Henderson (Edinb. Geol. Soc.),
obtained by him at the Gilmerton Quarry, near Edinburgh. Upon
forwarding it to Prof. de Koninck, the latter was kind enough to
inform me it was his P. humilis, a new form then in course of
description from the Rev. W. B. Clarke’s collection of N. 8. Wales
Carboniferous fossils. It has since been published in the above
work. The discovery of this species by Mr. Henderson in our
Lower Carboniferous Limestone Group is a fact worthy of record.

6. AscopIcTyon sTELLATUM, Nicholson and Etheridge, jun. (Ann.
Nat. Hist. 1877, vol. xx. p. 464, t. 19, f. 1-6).—The British species
of this provisional genus was A. radiatum, N. and H. Evidence has
now been obtained by Mr. J. Bennie, which will probably indicate
A. stellatum, N. and H., also as British. A fragment of a Crinoidal
stem has scattered over it a number of vesicles united by creeping
stolons or fibres, so closely resembling those figured by Prof.
Nicholson and myself as the oval young (?) vesicles of this species,
that I see no reason, so far as the evidence at my command goes, to
doubt the identity of the forms.

C. Callaway—L. Helderberg Group of N. York. 271

VI.—On THE CorrRELATION oF THE LowreR HELDERBERG GROUP OF
New York.
By C. Cattaway, M.A., B.Se., F.G.S.

PROPOSE in this paper to give the evidences for the strati-

graphical position of this interesting group, both because the
task, so far as I am aware, has not been attempted in detail, and
because American geologists themselves are not altogether agreed on
the subject, some maintaining the equivalence of the group with our
Ludlow, while there are a few who regard it as an easterly exten-
sion of the Niagara series of Western New York. Having had an
extensive practical acquaintance with the fossils of New York, in
the State Museum, and having supplemented cabinet study by work
in the field, I venture to hope that I may be able to determine the
question to the satisfaction of geologists.

1. Sketch of the group in the typical area in New York.—The Hel-
derberg Mountains form a low range striking in a comparatively
straight line from the valley of the Hudson south of Albany on the
east through Albany county to Schoharie county on the west.
They present a steep escarpment to the north, overlooking the
Mohawk, a western tributary of the Hudson. To the south, the
ground gradually slopes downwards for several miles, then rises
more abruptly into the bold masses of the Catskills. The base of
the Helderberg escarpment generally rests upon the unconformable
beds of the Hudson River group. The escarpment itself mainly con-
sists of limestones of Lower and Upper Helderberg age, with a thin
basement of Clinton and Niagara rocks, and a considerable capping
of arenaceous shales of the Hamilton group. The following cut
represents the section from the valley of the Mohawk on the north
to the Catskills on the south.

SECTION 1.

Mohawk R. Helderberg Mts. Catskill Mts.

a= Hudson River group. ad=Lower Helderberg group.
6=Clinton shales. e=Upper ditto (Lower Devonian).
ce=Niagara Limestone. f=Middle and Upper Devonian.

The above section shows the relation of the Lower Helderberg
to the formations above and below. The next is on a larger scale, °
and is designed to display the subdivisions of the group. The section
is taken through the escarpment overlooking the village of Schoharie,
to the south-west of Albany.

Ascending the escarpment from Schoharie, we find at its base a
thin bed of greenish shale charged with iron pyrites, the probable
easterly attenuation of the Clinton (Upper Llandovery) series. Form-

212 CO. Callaway—L. Helderberg Group of N. York.

ing a thin cornice overhanging the shale are a few feet of coralline
limestone, the meagre representative of the Niagara (Wenlock) group
of Western New York. We next come to the Water-lime rock, so
named from its use for hydraulic cement, a dolomite rendered impure

SEcTION 2.

=

d=Lower Helderberg group :—

a= Hudson River group. d'=Tentaculite Limestone.
6 =Clinton shales. d? = Lower Pentamerus Limestone.
e=Niagara Limestone. d* = Delthyris Shaly Limestone.
= Water-lime group (Onondaga Salt d*=Upper Pentamerus Limestone.
group). e= Upper Helderberg group.

f=Hamilton group.

by silica, alumina, and iron peroxide. It represents the great saline
series of Onondaga county, the Onondaga Salt group. the equivalent
of the upper part of our Wenlock series. Next in order we have the
four members of the Lower Helderberg. First, a thin band of a
clinking limestone full of a Tentaculite, the Tentaculite Limestone.
Then comes the Lower Pentamerus Limestone, a massive thick-bedded
series, 50 feet in thickness, characterized by the abundance of Penta-
merus galeatus. ‘The preceding limestone beds form a bold escarp-
ment, in some places falling down in a vertical precipice. Overlying
the Lower Pentamerus Limestone is the Catskill or Delthyris Shaly
Limestone, a calcareous shale with impure thin-bedded limestones.
Being much softer than the limestones above and below, this shale is
hollowed out, and forms a gentle slope rising up to the fourth sub-
division, the Upper Pentamerus Limestone, a thin band which over-
hangs the shaly beds in a well-marked cornice. It is characterized
by the abundance of another species of Pentamerus, P. pseudogaleatus,
The different members of the Upper Helderberg succeed, capped by
the Corniferous Limestone. A profile of the hill thus shows three
bold steps or terraces formed respectively by the Lower Pentamerus,
the Upper Pentamerus, and the Corniferous Limestones. With the

last of these we have not here to deal.
2. Stratigraphical evidence.—Some American geologists have main-
_tained that the Lower Helderberg group is the easterly extension of
the Niagara series of Western New York, the equivalent of our
Wenlock. This identification appears to be based upon certain pale-
ontological resemblances between the two formations, which I shall
discuss farther on. It has probably received support from the fact
that both the Niagara of Western New York and the Lower Helder-
berg of the Hastern end of the State hold a similar relation to the
overlying Upper Helderberg Limestone. In the Helderberg range

C. Callaway—L. Helderberg Group of N. York. 273

the Lower Helderberg group occupies the chief space between the
Cambro-Silurian and the Upper Helderberg, and this holds good also
of the Niagara group in the west. The following section will explain’
this misconception, and at the same time show the true relation of
the deposits in- question.

SEcTion 3.
Eastern New York. Western New York.
a eS
6
5 &
z : See
1 i

7. Te Helderberg Group. 3. Clinton Group.

6. Lower do. do. 2. Medina Sandstone.

5. Water-lime Group. 1. Hudson River Group.

4, Niagara a

This section is about 200 miles from east to west. Being drawn
from memory, it does not pretend to be an accurate representation of
the comparative thickness of the beds. It shows the relations of the
groups, with an approximation to the thickness, which is all my
purpose requires. It will be seen that the Hudson River shales and
slates form the basis of the whole succession. The Medina Sand-
stone is a considerable formation on the Niagara and Genesee Rivers,
but thins out towards the middle of the State. The Clinton Lime-
stone and Shales are in force in the same localities, but to the east,
in the Helderbergs, it has thinned out to a shale of seven or eight
feet in thickness. The Niagara Limestone and Shale thin out in the
same direction, and are represented at Schoharie by two or three feet
of coralline limestone. The Saliferous or Water-lime group is per-
sistent in varying thickness from west to east. The succeeding
Lower Helderberg rocks, however, are the converse of the preceding ;
and, from a thickness of over 200 feet in the east, thin out entirely
towards the western side of the State. The limestone capping of the
Upper Helderberg series extends in an unbroken band from east to
west, overlapping the Lower Helderberg on to the Water-lime, and,
beyond the western boundaries of the State, overlapping the Water-
lime on to the Niagara Limestone itself. This section, if accurate, .
decides the question ; and of its accuracy 1 have no doubt. I have
made numerous traverses across it in both eastern and western New
York. I have, furthermore, the unimpeachable testimony of Professor
James Hall to the effect that he has traced the several formations
from east to west, and he has assured me in repeated conversations
that the section is substantially as I have represented it. The Lower
Helderberg group, therefore, clearly overlies rocks of the Niagara
period. It is also distinctly separated from the Niagara by the charac-
ter of its fauna. The only species known to me as common to the
two formations are Atrypa reticularis and Strophomena rhomboidalis.
Of these A. reticularis ranges from Middle Silurian to the Carbon-
iferous, and S. rhomboidalis from Lower Silurian to the Carboniferous,
so that their testimony does not in the slightest degree militate against
my position. This evidence is very decisive, when we remember that

DECADE II.—VOL. V.—NO. VI. 18

™

274 C. Callaway—L. Helderberg Group of N. York.

the two formations compared are similar in lithological composition,

both being composed of limestones and calcareous shales; and that

both were deposited in the same area. The difference in the facies
of the fauna is not, however, so marked as to indicate a very wide
break in time. There is a like abundance of the genus Platyceras.

Many species of Trilobites and Brachiopods are similar, especially in

the genus Dalmannia amongst the former, and in the genera Rhyncho-

nella, Meristella, Spirifera, Leptocelia, Orthis, and Strophomena (Strep-
torhyncus), amongst the latter. Towards the close of the Niagara
period, there was an upheaval of the sea-bottom with the formation
of salinas and the deposition of dolomite. In the subsequent de-
pression towards the east, the Lower Helderberg beds were deposited.

The difference between the two faunas is just what we should expect

from this change of conditions and lapse of time.

3. Paleontological evidence.—I have endeavoured to show that the
Lower Helderberg group overlies, and is distinct in its fauna from,
the Niagara rocks. The latter group is the undoubted equivalent of
the Wenlock series, so that on stratigraphical grounds the Lower
Helderberg would appear to be on the horizon of our Ludlow
rocks.

A preliminary difficulty must be first discussed. There are certain
fossils, or groups of fossils, which confuse the general evidence of
the respective faunas. The Lower Pentamerus Limestone derives
its name from the great abundance of Pentamerus galeatus. In
Britain this form is common in the Wenlock, and occurs less
abundantly in the Lower and Middle Ludlow. It is also described
by De Verneuil from supposed Devonian limestone in the South
Urals. As itis found ata lower horizon in Britain than in America,
Professor Hall has intimated great doubt of the correctness of the
British identification; but as I have myself collected the species in
Wenlock Limestone quarries near Wenlock, I am bound to maintain
that it is a Wenlock species. The supposed difficulty is easily
removed on the hypothesis of an east to west migration. A much
more serious objection to the Ludlow age of the Lower Helderberg
is the following. In the Ludlow we have an abundant lamelli-
branchiate fauna, the genera Péerinea, Cypricardinia, and Goniophora
being especially characteristic. This assemblage does not occur in
‘the Lower Helderberg, but in the Hamilton group it is represented
by many of the same genera, and by numerous allied species. In
other respects, the facies of the Hamilton fauna is decidedly De-
vonian. The following analysis of the principal genera and species
will set this in a sufficiently clear light. I give only those which
are of value for our purpose :—

Pruant.—Caulopteris, Psaronius, Lepidodendron, and Sigillaria are quoted from
the Hamilton rocks of Pennsylvania and New York.

Anrnozoa.— Heliophyllum Halli, Edw. (very common). Quoted in Morris’s British
Fossils under the name of Strephodes helianthoides, Goldf., from the Devonian
Limestone of Devonshire and the Eifel.

Bracuropopa.—Crania Hamiltonie, Hall. Said by Hall to resemble C. obsoleta,
Goldf., from the Eifel.

Orthis Vanuxemi, Hall, O. leucosia, Hall, O. Penelope, Hall. All of these closely

resemble O. Michelini, Leveillé, a Carboniferous form.

C. Callaway—L. Helderberg Group of N. York. 275

O. Tulliensis, Vanuxem. Of the type of O. resupinata, Martin, of our Devonian
and Carboniferous.

Streptorhynchus Chemungensis, Conrad. Similar to S. crenistria, Phil., of the Euro-
pean Devonian and Carboniferous.

Strophodonta inequistriata, Conr. At one time identified by Hall with Orthis
interstrialis, Phil., and now doubtfully separated. 0. (?) interstrialis is a
Devonian fossil.

S. nacrea, Hall, almost identical with S. Zepis, Bronn. Devonian.

Productella, gen. Species numerous. This genus is essentially a Producta, differ-
ing from it only in the possession of inconspicuous hinge-teeth and sockets.
Producta is characteristically a Carboniferous genus.

Cyrtina Hamiltonensis, Hall. Closely allied to C. heteroclita, Defr., of the De-
vonian limestone of Europe.

Athyris spiriferoides, Eaton. Barely separable from A. concentrica, von Buch, an
Upper Devonian fossil.

Atrypa aspera, Schlot. A common European Devonian form,

Rhynchonella venustula, Hall. Identified by Conrad with R. cuboides, Sow., one
of our common. Devonian species; but separated by Hall for some very slight
differences.

CEPHALoPoDA.—Several species of Goniatites have been found in the Marcellus
Shale, the base of the Hamilton group. :

Crustacea.—Phacops rana, Green. Closely representative of P. datifrons, Bronn, of
the British and Continental Devonian rocks.

I rely less, however, upon individual species than upon the
general facies of the fauna, and the relative proportions of the
numbers of the genera and species. In collecting in Western
New York, and in reviewing and arranging large series of speci-
mens in the New York State Museum, the forms which were
everywhere turning up were Spirifera, Chonetes, Strophodonta, Atrypa,
Cyrtina, and these of Devonian or even Carboniferous facies. The
genus Productella is also very significant. Of species the most
abundant are Orthis Vanuwemi, Strophodonta inequistriata, Spirifera
mucronata, Athyris spiriferoides, Atrypa aspera, Cyrtina Hamiltonensis,
Heliophyllum Halli, and Phacops rana, all of them represented by
identical or closely allied forms in European Devonian or Carboni-
ferous rocks. On the other hand, the Ludlow-like Lamellibranchs
are comparatively rare.

The formations underlying the Hamilton must also be taken into
account. In the Schoharie Grit, fishes make their first appearance ;
and, in the later epoch of the Upper Helderberg Limestone, this
class is abundantly represented. The types are clearly those of the
European Old Red Sandstone. Macropetaliehthys resembles Pterichthys.
Forms like Cephalaspis and Holoptychius also occur. Of plants,
Caulopteris is found in marine limestones below the Hamilton group
in Ohio, and Lepidodendron is quoted by Professor Newberry from
the same limestone. Generally speaking, the fauna of the Upper
Helderberg is intermediate in character between the underlying
Lower Helderberg and the overlying Hamilton.

The general testimony of the fossils is clearly in favour of the
Devonian age of the Hamilton group, and the exceptional character
of the lamellibranchiate fauna is probably to be explained on the
supposition that certain causes, biological or otherwise, retarded the
migration of the European Ludlow Conchifera to the western seas.
Their occurrence in the Hamilton would hardly seem to be sufficient

276 C. Callaway—L. Helderberg Group of N. York.

ground for extending the Ludlow upwards so as to include the
Hamilton group, as some American geologists are disposed to do.

The formation underlying the Lower Helderberg being the
equivalent of the Wenlock, and the formations overlying being
clearly correlated with our Devonian, it is fair to conclude that the
Lower Helderberg group represents our Ludlow.

A comparison of the Ludlow and Lower Helderberg faunas will
not supply us with additional evidence of a very decisive character.
Putting on one side the exceptional case of the Conchifera, the
Ludlow fauna has no close resemblance to any American formation.
Of individual species, we may compare Phacops (Dalmannia) longi-
caudatus with the much larger Dalmannia nasuta, Rhynchonella
Wilsont with R. ventricosa, and Strophomena euglypha with S. punc-
tulifera. In the Aymestry Limestone near Broseley, I have also
detected Orthis plano-convexa of the Lower Helderberg. But of the
numerous Cephalopoda of our Lower Ludlow, we have few, or no,
representatives in the American area. On the whole, the Lower
Helderberg fauna resembles that of the Niagara series of New York
more closely than it resembles that of the British Ludlow. The
explanation of this is not far to seek. At the close of the Niagara
period, the sea shallowed, and salt lakes were formed. But this
elevation was followed by a marine epoch, during which the Niagara
fauna, driven into adjacent seas by this local upheaval, would return
to their old habitat, modified in form to such a degree as we might
expect from the interval of time represented by the Salina period.
The Lower Helderberg corals and molluscs flourished in the same
area as, and on a similar sea-bottom to,.the Niagara fauna. But in
the British area the conditions were different. During the Ludlow
period, the sea was gradually shallowing, so that towards its close
the proximity of land is indicated by arenaceous strata and the
presence of land-plants, and of fishes, as Pteraspis, which probably
inhabited fresh-water. A change from a calcareous to a sandy sea-
bottom, and from marine to land and fresh-water conditions, would
produce a change in the fauna much more rapidly than a mere lapse
of time. In the New York area, terrestrial conditions do not set in
till the Hamilton period, and, with the coming in of a sediment
similar to the Upper Ludlow rock, we have the advent of the
Ludlow Lamellibranchs.. But where the Hamilton rocks lose their
arenaceous character, and pass into calcareous strata, as in Western
New York, the Lamellibranchs grow scarce, and the prevailing
forms of life are Brachiopoda and Corals of Devonian types.

In correlating rock systems, the work is comparatively easy when
the physical conditions under which their faunas flourished were
similar. We can compare arenaceous Coal-measures in Europe with
arenaceous Coal-measures in America; or a calcareous Wenlock with
a calcareous Niagara, and our conclusions are clear and satisfactory.
But changes in sediment, and other physical causes, introduce great
complexity into the evidence. I do not, however, despair of obtaining
true results when, as in the above case, we know the formations
above and below the groups which we wish to correlate. Our base-

Prof. T. Ripert Jones— Wealden Entomostraca. ate

line, a calcareous Wenlock-Niagara Series, is clear. A second
level, a calcareous Hamilton-Devonian, is also reasonably distinct.
The intermediate zone, the paleontological evidence of which is
confused by differences of physical conditions, may fairly be inferred
to hold a middle place between Wenlock and Devonian. If, indeed,
there is no Devonian, as some have suggested, my argument will
require to be remodelled; but it is difficult to study the magnificent
series which intervenes between true Silurian and true Carboniferous
in New York and Pennsylvania, and to come away with the con-
clusion that it is a mere base to the Carboniferous.

VII.—On toe Weranpen ENTOMOSTRAGA.
By Prof. T. Rupert Jonzs, F.R.S., F.G.S.

SEND as a Supplement to my last communication the subjoined

Synoptical view of the species of Wealden Entomostraca,

treated of in the March Number of the Grou. Mage., trusting it
may prove acceptable to both collectors and systematists.

TABULATED VIEW OF THE PuURBECK-WEALDEN ENTOMOSTRACA OF ENGLAND, AS
AT PRESENT KNOWN.

I.—From the Wealden Beds of the Southern Counties.

1. Cypridea Valdensis (Sow. and Fitton).! Sowerby’s ‘‘ Min. Conch.,” pl. 485,
(Cypris faba). :
—— Austeni, Jones. In Fitton’s plate; “Trans. Geol. Soc.,” ser. 2,
vol. iv. pl. 21, fig. 1; Grou. Mac. Dee. II. Vol. V. p. 109, 110, Pl. III. Fig. 8.
? tuberculata (Sow.). Ibid. p. 104, 105, Pl. III. Figs. 20, ¢.
2 Fittoni (Mantell). Ibid. p. 104, Pl. III. Fig. 2a.
? granulosa (Sow.). Ibid. p. 104, 100, Pl. III. Fig. 4.
spinigera (Sow.). Ibid. Fig. 3.

TL —From the Neocomian Freshwater Sands of Shotover, near
Oxford.

7. Candona Phillipsiana, Jones. Grou. Mac. Dee. II. Vol. V. p- 108, Pl. III.
Fig.3.

8. Cypridea verrucosa, Jones. Ibid. Fig. 5-7.
9. ————_ , var. crassa, Ibid. Fig. 4.

RS)

> Ove OO

10. ———— bispinosa, Jones. Ibid. p. 109, Pl. III. Fig. 9-10.
11. ———— Valdensis (Sow. and Fitton). bid. Fig. 11.
12. ———— Austeni, Jones. Ibid. p. 109, 110, Pl. III. Fig. 8.

IiI.—From the Purbeck Beds of the Subwealden Boring in Sussex.

13. Cypridea Valdensis (Sow. and Fitton). Gurox. Maa. Dec. II. Vol. V. p. 110,
Pl. III. Fig. 13-15.

14. ———— granulosa (Dunker). Ibid. Fig. 16.

Besides some undetermined specimens. did. p. 110.

TV.—From the Purbeck Beds of Dorsetshire.

a.—Uprer PURBECK.
15. Cypris ? gibbosa, KE. Forbes (near C. spinigera, Sow.)
16. ———— ? tuberculata, K, F. (near C. tuberculata, Sow.)
17. ———— ? leguminella, K. F.
6.—M1ppLE PURBECKE.
18. Cypris ? striatopunctata, HK. F. (? Fr. A. Romer.)

" This is the species generally referred to by Dr. Fitton in his Memoir, but not
the form figured by. him in his plate.

278 Notices of Memoirs—Dr. G. Linnarsson—Graptolite Schists.

19. Cypris ? fasciculata, EK. F.
20. — ? granulata, K. F. (? C. granulosa, Dunker.)
c.—LowER PURBECK.
21. Cypris ? Purbeckensis, K. F.
22: ? punctata, K. F.
These are figured in Sir C. Lyell’s “‘ Manual of Geology,” see Grou. Mac. /.c. p. 105.

Note oN THE DISTRIBUTION OF THE SPECIES.

Nos, 1, 11, and 13. Ve common throughout the Wealden and in some Purbeck beds; also in
ermany.
2 and 12. Rather one Figured by Fitton from some unmentioned locality ; Peasemarsh,
Surrey; Shotover.
3 and 16, Not uncommon in the Wealden Beds. In the Upper Purbeck.
4, Accompanies C. tuberculata in some places.
5. Hastings beds of Sussex ; Purbeck beds of South Wilts.
6. Not uncommon in the Wealden beds,
7. Shotover; Obernkirchn, Hanover.
8 and 9, Shotover.
10. Shotover.
14 and 20? Subwealden Boring, Sussex ; Hanover; Middle Purbeck of Dorset?

Addenda et Corrigenda.—At page 101, line 25, add: It occurs
throughout a bed about 15 feet thick, and is very characteristic of
the zone. Atp.101, add: Estheria tenella (Jordan), “Monogr. Foss.
Kstherie,” 1862, p. 31, etc., has been found abundantly by the
Geological Surveyors of Scotland in the Coal-measures near Airdrie;
and, in one instance (at Glenmavis Burn), it constitutes a bituminous
shale, so thickly are the individuals massed together. From Palace-
craig, near Airdrie, where H. tenella has lately been obtained, I
remember to have seen specimens of a much larger Hstheria, since
lost. At p. 102, line 16 from bottom, for Fred. read Ferd. At
p- 105, line 28, for on read in. Line 82, after figured specimen,
add: = Cypridea Austent. At p. 109, line 8 from bottom, add:
Mr. H. Caudell has also found Cypridea Valdensis in the Ironstone
of Wheatley, two miles 8.H. of the other locality.

IN(CwRIRCHEHS) (ser IMM McOunsys.

J.—On THE GRAPTOLITE Scuists oF KonGSLENA IN WESTROGOTHIA,
Swepen.’ By Dr. G. Liynarsson, Director of the Geological
Survey of Sweden.

N the Upper Graptolite schists of Westrogothia two divisions are
recognizable—a lower division characterized by Monogr. lobiferus

(M‘Coy) and Rastrites peregrinus (Barr.); and a higher division

characterized by Monograpt. priodon (Bronn) and Retiolites Geinitz-

ianus (Barr.). The same divisions, well separated, appear in other

parts of the country, and Tornquist has. already proposed for them

the respective titles of the Lobiferus Schists and Retiolites Schists.”
Among the localities in Westrogothia where the Upper Graptolite

Schist is most accessible is Strommen in the parish of Kongslena.

These schists, as well as the immediately underlying strata, the

Brachiopod Schists and the Trinucleus Schists, are locally cut into

by a considerable stream. The Lobiferus Schist is here a black

1 Abstract of a paper published in the Geologiska Féreningens i Stockholm Fér-
handlingar, 1877, Nr. 41; Bd. III., Nr. 13.

2 Tornquist, Ofvers. af K. Vet, Akad. Férhandl., 1875, p. 57.

Notices of Memoirs—Dr. G. Linnarsson—Graptolite Schists. 279

thinly laminated straight-cleaving schist crowded with Graptolites,
which appear as thin shining films of iron-pyrites. It rests upon
the Brachiopod Schists, and is surmounted by a grey flag-like rock,
which has not hitherto yielded fossils, but possibly represents the
Retiolites Schist.

At the time the author described the sequence of the Silurian rocks
of Westrogothia some years ago,!a very small number of species
only had been detected at Kongslena. In the summer of 1876, in a
fresh visit to this locality, he was fortunately able to add greatly to
his former discoveries. In specific richness the Lobiferus Schist at
this spot now exceeds that of all other known Swedish localities.
The description of several forms which appear to be new is best
deferred till more and better material has been obtained; and the
state of preservation of others which are already named does not
admit of their certain identification. The following list is therefore
far from complete.

Graptolites from the Lobiferus Schist of Kongslena.

Monograptus lobiferus, M‘Coy. Rastrites peregrinus, Barr.
sagittarius, His. Diplograpt. palmeus, Barr.

— Sandersoni, Lapw. ofr. modestus, Lapw-
——— Sedgwicki, Portlk. cometa, Geinitz.
——_— spiralis, Geinitz. — tamariscus, Nich.
triangulatus, Harkn. Climacogr. rectangularis, M‘Coy.

Schists with a similar fauna occur not only in Westrogothia, but
in many other districts in Sweden, as in Dalarne and Scania.

In the island of Bornholm it is probable that the Lobiferus Schist is
paralleled by the lower portion of the graptolitiferous schists which
are denominated by Johnstrup? the Uppermost Graptolite Schists.
In Norway and the Russian Baltic Provinces no precise equivalents
of the Lobiferus Schist are known. It is not improbable that beds of
the same age may exist there, but if so, they have so wholly different
a facies that it is impossible to compare them. Very different how-
ever is their correlation with the Silurian rocks of Britain. If we
examine a list of the fossils of the latter, we recognize almost all the
above-mentioned Graptolites. Notwithstanding this, however, it
was formerly impossible to parallel the Lobiferus Schist with any
special portion of the English succession as arranged by Murchison.
This was mainly owing to the circumstance that these Graptolites
had not been discovered in the districts whence Murchison drew the
types for his Silurian system. In other parts of the country, as in
the Coniston and Moffat Groups of the Lake District and the South
of Scotland, they have long been known; and it has already been
shown by the author? that these include equivalents of the Upper
Graptolite Schists. But respecting these, and the other British
graptolitie deposits relatively older, we have always had very

1 Linnarsson, Om Vestergétlands Cambriska och Siluriska aflagringar, K. Vet.
Akad. Hand., Bd. 8, Nr. 2, 1869.

2 Johnstrup, Oversigt over palewozoiske Dannelser paa Bornholm, Forh. vy. d.
Skandinay. Naturf. 11te. sid 307.

3 See, for example, Linnarsson, ‘‘ On the Vertical Range of Graptolites im Sweden,”
Grou. Mag. Dee. II. Vol. III. 1876.

280 Notices of Memoirs—Dr. G. Linnarsson—Graptolite Schists.

incorrect ideas. In the Catalogue of the Silurian Fossils given by
Murchison (Siluria, 4th edition), several of the above-mentioned
fossils are included, such as Monogr. lobiferus (= Becki) and M. sagit-
tarius, Rastrites peregrinus and Diplogr. cometa, but all are placed
under the head of the Llandeilo formation. In his description of
the Silurian succession in Westrogothia, the author was therefore
compelled to parallel the Upper Graptolite Schists with a part of
Murchison’s Llandeilo, though with an intimation that Murchison’s
arrangement must somehow have been erroneous, in thus assigning
them a systematic position inferior to the Chasmops Limestone and
Trinucleus Schist, which of all Swedish beds most nearly resemble
the Caradoc, and actually underlie these Upper Graptolite Schists.
In the list of British Graptolites given by Nicholson in his Mono-
graph’ he includes many of the Graptolites of the Lobiferus Schist.
The majority, such as Jf lobiferus and sagittarius, Ras. peregrinus
and Diplogr. tamariscus, are said to occur both in the Upper Llandeilo
and in the Caradoc. Diplo. cometa is given from the Upper Llandeilo
only. To judge from this, the Lobiferus Schist ought best to be
compared with the transition beds between the Llandeilo and
Caradoc. Even this, however, conflicts with the above-mentioned
fact that the Lobiferus Schist reposes upon strata, the fauna of
which most nearly corresponds to that of the Caradoc.

For the first time, through Lapworth’s accurate researches in the
South of Scotland, has the Graptolite-bearing series in Great Britain
been developed in a satisfactory manner. He divides the richly
graptolitic Moffat group into three parts—the Lower or Glenkiln
Shales, the Middle or Hartfell Shales, and the Upper or Birkhill Shales
—of the fossils of which he gives a catalogue.? According to this,
we find that the Upper Moffat (Birkhill Shales) completely parallel-
izes with the Lobiferus Schist. Nearly all the Graptolites we find at
Kongslena are found in the Upper Moffat, and none of them are
mentioned from either of the underlying divisions. The Middle
Moffat, again, is the equivalent in time of the Schists with Dicrano-
graptus Clingant and Diplogr. foliaceus, which occur in Scania, as
at Fogelsang, Josterup, and Jerrestad. This close concordance with
the Swedish succession shows that we may, without doubt, look
upon Lapworth’s classification of the Scottish series as being
correct. As regards the systematic relations of the Scottish rocks
to the typical English series again, Lapworth holds totally different
views from those of preceding authors. In the Moffat group, for
example (which Murchison and Nicholson—the latter at least in
1872—regard wholly as Llandeilo), Lapworth considers that the
Lower Moffat only belongs to the Llandeilo, the Middle Moffat to
the Caradoc ; while of the Upper Moffat it is said that it “seems
to belong almost wholly to the Lower Llandovery.” This last-
mentioned comparison at least does not conflict with the Swedish
relations. That is to say, in several of the rock divisions, which

1 A Monograph of the British Graptolitida, Edin. & Lond. 1872, p. 97, et seq.
2 A Catalogue of the Western Scottish Fossils, Glasgow, 1876, p. 97, et seq.

Notices of Memoirs—Dr. G. Linnarsson—Graptolite Schists. 281

precede the Lobiferus Schist, the fauna has already appeared, which
is most nearly to be compared with that of the Caradoc group.

In the North of England again we meet with the Graptolites of
the Lobiferus Schists in that group of shaly strata called the
Coniston Mudstones.! According to the lists of their fossils given
- by Harkness and Nicholson, they include a Trilobite fauna having a
thoroughly Lower Silurian aspect, and which can best be compared
with that of the Trinucleus Schiefer. Till this abnormal relation-
ship has been confirmed, the author is of opinion that we ought to
be allowed to believe that some mistake has been committed.

Several of the fossils of the Lobiferus Schist, such as M. lobiferus,
Moy, M. spiralis, Rastrites peregrinus and Diplograpt. palmeus, are
found also in Bohemia, partly in Barrande’s Etage Hel, and partly
in the Colonies in his Etage D.? On both stratigraphical and
' paleontological evidences, the author had already paralleled the
Lobiferus Schists, in common with the Upper Graptolite Schists,
with the Etage Eel. 'Térnquist, on the contrary, has suggested that
the Upper Graptolite Schists are rather contemporaneous with the
Colonies. This last view is chiefly founded upon the supposed
English succession; but now, since this has been more accurately
determined, the facts give force, on the other hand, to the author’s
opinion. It was formerly supposed that the fauna which characterized
the Swedish Upper Graptolite Schists belonged to the Llandeilo and
Caradoc. It is now proved that they belong to the Middle and
Upper Silurian strata. As regards the equivalents of the Lobiferus
Schist—the Birkhill Shales and the Coniston Mudstones—the former
are believed by Lapworth to belong to the Lower Llandovery ; the
latter by Harkness and Nicholson to the Uppermost Bala or Lowest _
Llandovery.

The Coniston Flags, which in their strata and fossils may be com-
pared with the Retiolites Schists, are now regarded by English
authors as an Upper Silurian formation. In England, therefore, as
well as in Sweden and Bohemia, these special Graptolite faunas thus
stand in near relation to the Upper Silurian formations. Their
appearance in ¢rue Lower Silurian formations is, on the contrary,
peculiar to Bohemia. The Leptena Limestone, which overlies the
Upper Graptolite Schists, can scarcely be mentioned as true Lower
Silurian ; while the Brachiopod Schist, which underlies the Lobiferus
Schist, has already a far greater Upper Silurian aspect than even the
very highest strata of Barrande’s Etage D. These last-mentioned
beds agree nearest with the lower part of the Trinucleus Schists of
Sweden. Naturally, perfect synchronism between the Swedish
Upper Graptolite Schists and the Bohemian Etage Hel, can hardly
be said to be actually demonstrated. They are, however, at any rate,

1 See, for example, the list given by Harkness and Nicholson, Quart. Journ. Geol.
Soe., London, vol. xxxiii. 1877, p. 473. The Coniston Mudstones are not, as asserted
by these authors, equivalent to the whole of the Swedish Upper Graptolite Schists.
The Retiolites Schists are clearly older and are related to the Coniston Flags.

2 Vide Barrande, Defense des Colonies, 1870, vol. iv. p. 125. ,,

3 Térnquist, Om Siljanstraktens paleozoiskas formationsled, Ofvers. af K. Vet.
Akad. Forhandl., 1874, Nr. 4, p. 24.

232 . Notices of Memoirs—Prof. J. Woldrich on Canide.

homotaxeous, and for the present nothing is known which would lead
us to suppose that one was older than the other.

It has long been the general opinion that the Graptolites which
characterize Barrande’s Colonies and his Etage Hel, had originally
their home in the N. of Europe, and that from thence they made
excursions into the Bohemian basin. In their earlier migrations ~
they could not find complete footing there, and consequently formed
a colony which soon died out. Later, viz. at the time of the
formation of Barrande’s Htage Hel, they established themselves
in permanent occupation of the Bohemian basin.

Formerly, when it was thought that the Graptolites of the Upper
Graptolite Schists were co-existent with the Trilobites of the Tri-
nucleus Schists, and that their equivalent English Graptolite-bearing
beds belonged to the Llandeilo and Caradoc, such a view was very
natural. Now, however, the better insight we have attained of the
English and Swedish succession has robbed it of all its force. There
is now no reason to believe that the Graptolites which inhabited
Barrande’s Colonies had emigrated from the ocean of the north.
Where they came from is, at least for the present, impossible to
determine ; but probably the Bohemian Colonies are older than all
the Swedish and English beds in which the same fauna is found.
Instead of the emigration having taken place as believed hitherto,
if we may judge from the facts already obtained, it would rather
have taken place in the opposite direction.—Caru Faye.

II.—Pror. J. Wonprice—On Puxrstocens Canipz.
(Imper. Acad. Vienna, Meeting April 4, 1878.)

The remains found in the Loess of Lower Austria and in the
Caves of Franconia, Wiirttemberg, and Moravia prove the family of
Canid@ to have been represented in Europe during the “ Diluvial”
(Pleistocene) period, in its Lupine or Wolf type by the genera—
Cyon (2 species), Lycorus (1 sp.), Canis (1 sp.), Lupus (4 sp.); and
in its Vulpine or Fox type by the genera — Vulpes (4 sp.) and
Leucocyon (1 sp.): altogether 13 species. A nearly complete skele-
ton of Lupus Suessi, now in the University Museum at Vienna,
was found some years ago in the Loess of Nussdorf, N.W. of
Vienna, overlying the plastic clay of Hernals. This species was
characterized by a powerful and not very large head, a very strong
neck, and a vigorous muscular system. It was more robust than
Lupus speleus; and intermediate in size between that species and
the existing Wolf. The structure of its extremities shows that it
was fleet enough to pursue even the larger Herbivores and strong
enough to overpower them.—Count Marscuat.

REVIEWS.
IJ.—Revvur bE GéoLociz pour LES Annius 1875 ur 1876. Par
M. Detzssz et M. De Lapparent. (Paris, 1878.)
fl ers constantly increasing numbers of geological papers published

in the various Journals, Proceedings, and Memoirs of Societies,
renders it difficult, at the present time, tor the student of the science

Reviews—Prof. ‘Coy on Victorian Fossils. 28:3

to become readily acquainted with the literature of the subject.
Special works, therefore, giving a periodical résumé of the different
widely scattered publications are not only a great boon, but attest a
self-denying and laborious energy on the part of the respective
editors. In this country we have the valuable Geological Record,
edited by Mr. Whitaker; in Switzerland the Revue géologique Suisse,
compiled by M. E. Favre; and in France the Revue de géologie,
under the able direction of MM. Delesse and De Lapparent, and
which has now attained its fourteenth year. The present volume
(1878), compiled with the same care and arranged in the same
manner as the previous ones, comprises the various papers on
geological and the allied sciences printed during the years 1875
and 1876, besides which are inserted many useful private communi-
cations forwarded to the editors by different geologists, and also (as
in previous volumes) the analyses of rocks which have been under-
taken in private laboratories, or in those of the Ecole des Mines or
the Ecole des Ponts et Chaussées. The classification of the subjects
is adopted from the Manual of Geology, by Dana and arranged
under the five chief divisions of Physiographical, Lithological,
Historical, Geographical, and Dynamical Geology, special attention
being given by M. Delesse to the researches on rocks and their
metamorphism.

The editors have noticed the works of more than 400 authors, and
have given a concise account of their contents, noticing to a greater
extent those not published in France.—J.M.

II].—Vicrortan Oreantc Rematns.—PropRomus OF THE PaLmion-
ToLoGy oF Victorta. Decade V. By Prof. F. M‘Coy, F.G.S., ete.
(Melbourne, 1877.)

ax figures and descriptions of the new or more characteristic

Victorian organic remains of each formation are continued by
Prof. M‘Coy in this fifth decade, which is, therefore, an assistance to
the field geologist in determining the approximate geological ages
of the various formations he may meet with. The present number is
of equal importance with the preceding ones, and contains illustra-
tions of fossils of much interest both to the Colonial and European
paleontologist, for some of the species noticed of Upper Silurian
mollusca are identical with well-known abundant and characteristic
forms of Hurope and North America, whilst others are representative.

So also with some Eocene forms, it is shown that the most careful

comparison is necessary to distinguish between species of Cardiwm

from the Tertiary strata of Australia and ourown country. The con-
tents of this number are various; the first two plates illustrate new
extinct species of Eared Seal (Arctocephalus Williamsi) from the

Pliocene strata of Queenscliff, and nearly related to the living genera of

the Southern Seas; the third, fourth, fifth, and ninth plates are devoted

to illustrations of some characteristic forms of Tertiary Mollusca, as

Waldheimia, Cardium, Spondylus, and Cypree; the sixth and seventh

plates contain many figures of Upper Silurian Brachiopoda. The

next plate illustrates a new spheroidal Tertiary species of Sponge,

284 Reports and Proceedings—

with the long slender siliceous spicules of the genus Tethya, and a
remarkable extinct gigantic species of Sea-pen, or Graphularia, allied
to that found in the London Clay of England, and closely allied to
the living form (Sarcoptilon) in Hobson’s Bay. Under this head,
Prof. M‘Coy suggests whether the supposed Mesozoic genus
Belemnites may have been a different interpretation of the same
object. The last plate gives further illustrations to those in pre-
ceding decades of the Graptolites of the gold-field slates, one a new
type, and the others identical with a species (G. Headi, Hall) found
in similar slates in Canada.—J.M.

ISPs OARS! NAN D) J>15(QOsT Ia IDA KES
Lau

Gronocican Socrery or Lonpoy.—April 17, 1878.—Henry Clifton
Sorby, Esq., F.R.S., President, in the Chairn.—The following com-
munications were read :—

1. “On the Geological Results of the Polar Expedition under
Admiral Sir George Nares, F.R.S.” By Capt. H. W. Votldens eA
F.G.S., and C. E. De Rance, Esq., F.G.S.

The authors describe the Laurentian gneiss that occupies so large
a tract in Canada as extending into the ‘Polar area, and alike under-
lying the older Paleozoic rocks of the Parry Archipelago, the
Cretaceous and Tertiary plant-bearing beds of Disco Island, and the
Oolites and Lias of East Greenland and Spitzbergen. Newer than
the Laurentian, but older than the fossiliferous rocks of Upper
Silurian age, are the Cape-Rawson beds, forming the coast-line
between Scoresby Bay and Cape Cresswell, in lat. 82° 40’; these
strata are unfossiliferous slates and grit dipping at very high angles.

From the fact that Sir John Richardson found these ancient rocks
in the Hudson’s Bay territory to be directly overlain by limestones,
containing corals of the Upper Silurian Niagara and Onondaga
group, Sir Roderick Murchison inferred that the Polar area was dry
land during the whole of the interval of time occupied by the.
deposition of strata elsewhere between the Laurentian and the
Upper Silurian; and the examination by Mr. Salter, Dr. Haughton,
and others of the specimens brought from the Parry Islands have
hitherto been considered to support this view. The specimens of
rocks and fossils, more than 2,000 in number, brought by the late
expedition from Grinnell and Hall Lands, have made known to us,
with absolute certainty, the occurrence of Lower Silurian species in
rocks underlying the Upper Silurian ; and as several of these Lower
Silurian forms have been noted from the Arctic Archipelago, there
can be'little doubt that the Lower Silurians are there present: also.
The extensive areas of dolomite of a creamy colour discovered by
M‘Clintock around the magnetic pole, on the western side of
Boothia, in King William’s Island, and in Prince of Wales Land,
abounding in fossils, described by Dr. Haughton, probably represent
the whole of the Silurian era and possibly a portion of the Devonian.

The bases of the Silurians are seen in North Somerset, and consist
of finely stratified red sandstone and slate, resting directly on the

Geological Society of London. 285

Laurentian gneiss, resembling that found at Cape Bunny and in the
cliffs between Whale and Wolstenholme Sounds. Above these sand-
stones occur ferruginous limestones, with quartz grains, and still
higher in the series the cream-coloured limestones come in. The
Silurians occupy Prince Albert Land, the central and western
portion of North Devon, and the whole of Cornwallis Island. The
Carboniferous Limestone was discovered, rising to a height of 2,000
feet, on the extreme north coast of Grinnell Land, in Feilden and
Parry Peninsulas, and contains many species of fossils in common
with the rocks of the same age in Spitzbergen and the Parry
Archipelago. being probably continuously connected with the lime-
stone of that area, by way of the United States range of mountains.
The coal-bearing beds that underlie the Carboniferous Limestones of
Melville Island are absent in Grinnell Land, but they are represented
by true marine Devonians, established in the Polar area for the first
time, through the determination of the fossils, by Mr. Etheridge.
In America a vast area is covered by Cretaceous rocks. The lowest
division, the Dakota group, contains lignite seams and numerous
plant-remains indicating a temperate flora; overlying the Cretaceous
series are various Tertiary beds, each characterized by a special flora,
the oldest containing subtropical and tropical forms, such as various
palms of Eocene type. In the overlying Miocene beds the character
of the plants indicates a more temperate climate, and many of the
species occur in the Miocene beds of Disco Island, in West Green-
land, and a few of them in beds associated with the 30-feet coal-
seam discovered at Lady Franklin Sound by the late expedition.
The warmer Hocene flora is entirely absent in the Arctic area, but
the: Dakota beds are represented by the “ Atane strata” of West
Greenland, in which the leaves of dicotyledonous plants first appear.
Beneath it, in Greenland, is an older series of Cretaceous plant-
bearing beds, indicating a somewhat warmer climate, resembling
that experienced in Egypt and the Canary Islands at the present
time. In the later Miocene beds of Greenland, Spitzbergen, and
the newly discovered beds of Lady Franklin Sound, the plants belong
to climatal conditions 30° warmer than at present, the most northern
localities marking the coldest conditions. The common fir (Pinus
abies) was discovered in the Grinnell Land Miocene, as well as the
birch, poplar, and other trees, which doubtless extended across the
polar area to Spitzbergen, where they also occur.

At the present time the coasts of Grinnell Land and Greenland are
steadily rising from the sea, beds of glacio-marine origin, with shells
of the same species as are now living in Kennedy Channel, extend-
ing up the hill-sides and valley slopes to a height of 1000 ft., and
reaching a thickness of from 200 to 300 ft. These deposits, which
have much in common with the “ boulder-clays” of English geolo-
gists, are formed by the deposition of mud and sand carried down
by summer torrents and discharged into fiords and arms of the sea,
covered with stone- and gravel-laden floes, which, melted by the
heated and turbid waters, precipitate their freight on the mud below.
As the land steadily rises these mud-beds are elevated above the sea.

286 Reports and Proceedings—Geological Society of London.

The coast is fringed with the ice-foot, forming a flat terrace 50 to
100 yards in breadth, stretching from the base of the cliffs to the sea-
margin. ‘This wall of ice is not made up of frozen sea-water, but of
the accumulated autumn snowfall, which, drifting to the beach, is con-
verted into ice where it meets the sea-water which splashes over it.

2. ‘On the Paleontological Results of the recent Polar Expedition
under Admiral Sir George Nares, K.C.B., F.R.S.” By Capt. H. W.
Feilden, R.A., F.G.S., and Robert Etheridge, Esq., F.R.S., F.G.S.

In this communication the authors brought before the Society the
paleontological results and details of the collection made by the
naturalists and other officers of the late expedition to the Arctic
Circle under Admiral Sir G. Nares. The purpose of the paper was
to record the presence of Silurian and Carboniferous fossils in the
highest latitude yet reached, 82° 45’ N. Of the former group 60
species have been determined, ranging from the Lower to the Upper
Silurian, both Llandeilo and Wenlock types being present and
numerous, notably in the class Heteropoda, two species of the genus
Maclurea and Bellerophon, with Strophodonta and Raphistoma, etc.,
also the genus Receptaeulites. Upper Silurian species of Actinozoa
belonging to Halysites, Favosiies, Heliolites, Favistella, Zaphrentis,
Ampleaus, Cyathophyllum, and Arachnophyllum were noticed, and
correlated with British forms when possible; but, on the whole,
the facies of the Coelenterata is American rather than European.
Amongst the Crustacea five genera were noticed—Bronteus, Caly-
mene, Encrinurus, and Proétus, all Upper Silurian; and the genus
Asaphus, associated with Maclurea, of Lower Silurian age. Ten
species of Brachiopoda belonging to the genera Pentamerus, Rhyn-
chonella, Chonetes, Atrypa, Strophomena, have been determined.

Collections were made from twenty localities, ranging from lat.
79° 34 to 82° 40’ N., notably the highest at Cape Joseph Henry,
where Capt. Feilden obtained a numerous Carboniferous-Limestone
fauna, numbering about thirty species, chiefly Brachiopoda and
Polyzoa, all determined species, and American in character rather
than British. Mr. Etheridge believed he had determined, through
certain forms of Brachiopoda, the presence in a ravine at Dana Bay
of the Devonian rock below the Carboniferous Limestone south of
Cape Joseph Henry and Feilden Isthmus, the want of plant-remains
preventing any correlation with the Ursa stage of Heer. It cannot
now be doubted that an extensive Silurian fauna extends to, and is
present from lat. 79° to lat. 82° N., illustrating both the lower and
upper divisions of this group of rocks, especially the equivalents of
our Wenlock series. Again, north of these there sets in a clearly
defined Carboniferous-Limestone fauna, reaching the extremity of
the highest latitude we know, and probably striking away beneath
the Polar sea to Spitzbergen, where the same species have been
described by Toula. The authors, through certain fossils, then
endeavoured to show that on the whole the facies of the Polar
paleeozoic fauna was more nearly allied to that of America than to
that of Europe, and thus must be correlated with it, although it was
shown that a large number of species are common to the two areas,

Correspondence—Prof. T, Rupert Jones. 287

especially the British Islands. The absence of Lamellibranchiata in
rocks older than the Tertiary was noticed as having special interest
in the physical history of the Polar seas in Paleozoic and Mesozoic
times. None have ever been detected in these rocks. The authors
stated that they had sought also for evidence of Trias and Permian
fossils in this and other collections made, but there appeared to be
none. They also discussed the question of the deposition and exten-
sion of the Lias as represented at Eglinton Island and Spitzbergen.
The authors furnished a Table showing the distribution of all the
species collected by the expedition from twenty localities.

CORRESPONDENCE.

SAND-WORN PEBBLES IN THE WEALDEN OF SUSSEX,

Str, — Being at Cuckfield lately, I obtained, by the kindness
of Mr. Henry Willett, F.G.S., some of the large pebbles and sub-
angular pieces of quartz, quartzite, and lydite from the conglom-
erate, or pebbly and gritty bone-bed, of the ‘“ Upper Tunbridge-
Wells Sandstone” in the quarry at Whiteman’s Green, near the
town. <A glaze-like polish in parts of some of these stones at-
tracted my attention; and, on looking at it with the microscope, I
discerned the delicate parallel striee which blown sand produces in
polishing rocks and stones exposed to its action.

One of these partially glazed stones from the Cuckfield grit has
also the triangular shape produced by the persistent action of blown
sand, and must have been long exposed to such influence on the
strand of the old Neocomian lake or estuary, before it was finally
imbedded among the grit and rolled bones. Notices of the con-
glomerate referred to above are given in Mantell’s “Geology of the
South-Hast of England,” 1833, p. 209, etc., and in the “‘ Memoirs
Geol. Survey” (Topley’s Weald), 1875, p. 98, and p. 187, note.

Yor«ktown, April 10, 1878. T. Rupert JONES.

THE PRESERVATION OF DEPOSITS OF INCOHERENT MATERIALS
UNDER TILL OR BOULDER-CLAY.

Srr,—Mr. 8. V. Wood, in his “Reply” (Grox. Mac. Dec. II.
Vol. V. p. 187), complains that I have not put the questions at issue
between us so incisively as he could have wished. I am sorry to
have so far disappointed my opponent, but it was not my intention
to controvert all his theoretical views. If he will look at the title
of my short paper, he will see that 1 confine myself to one point, »
namely, the preservation of interglacial deposits. Mr. Wood has
so frequently denied the possibility of interglacial beds having been
overflowed by glacier-ice, and so confidently asserted that my views
were self-contradictory, that I thought it worth while to point out
that his principal, indeed his only, argument was based upon what
he himself tacitly admits is merely a preconceived notion. Iam
glad to find, however, that in other respects his views approximate
to mine more nearly than he seems to be aware. Thus, he tells us
first, that he does not deny “that ice erodes more in some places
than in others ;” secondly, that he believes “some moraine accumu-

288 Correspondence—Dr. James Geikie.

lates below ice;” and thirdly, that it may to some extent be true that
ice does override incoherent deposits without entirely obliterating
them. But he instances the section exposed in the North Suffolk
Cliff, where Till rests for a long distance upon a comparatively
undisturbed surface of sand, as proving that the former deposit has
been laid down in the sea, and as demonstrating the physical
impossibility of its having been accumulated under ice. Here,
again, Mr. Wood’s argument is based as before upon the same
preconceived ‘notion. He quietly ignores all the positive evidence
which has. been adduced in proof of the subglacier origin and
accumulation of the chalky till of Suffolk, and brings forward not
one single jot or tittle of positive evidence in favour of his own view.
Yet, surely, if the Till in question were a marine formation, there
should be no lack of such evidence. If the chalky boulder-clay
were laid down upon the sea-bottom, a wide area in the south-east
of England must have been submerged, and that for a considerable
time. Where, then, I would ask, are the bedded gravel, sand, and
clay—the raised beaches and so forth—with marine organisms,
which we might reasonably expect to meet with? Where, in short,
are the beds equivalent in origin to the shelly brick-clays, etc., of
Scotland, Scandinavia, and Canada? Can it be that the sea-bottom
of glacial times, in the East Anglian district, was dredged with clay
and peppered with stones and boulders at so rapid a rate as to
render marine life impossible !

I quite agree with Professor Young that the question of the
origin of Till necessarily precedes that of the preservation of inter-
glacial deposits, and I have before now expressed myself to that
effect. In the short paper which has called forth his remarks, the
subject of the origin of Till was not taken up for the simple reason
that I had already discussed that question at sufficient length else-
where. I still think that the theory of the subglacier origin and
accumulation of Till meets every difficulty, and offers a satisfactory
explanation of all the phenomena, and I can only regret that my
friend is of a different opinion. The view which he inclines to
favour has at the first blush a plausible appearance, but it will not
stand a closer examination. 1 was myself disposed at one time to
think that the Till might have been deposited in the sea in front of
an ice-sheet. But the explanation completely failed when I came to
put it to the proof. The objections to it are well-nigh legion, but
only one of these need be mentioned here—not because it is the most
cogent, but because it can be stated in very few words. Wide-spread
and thick deposits of Till occur on the lee-side of the Sidlaws, the
Ochils, and other hill-areas in Central Scotland, and many of the in-
cluded boulders prove that the Till in question has been forced up and
over these hills. Now, if the hills were submerged at the time they
received their coverings of Till, where, let me ask, was the ice-sheet ?

Pertu, April 20th, 1878. JAMES GEIKIE.

Erratum.—From Mr. A. Champernowne, F.G.S. In Plate VI. Fig. 2 (of the May
Number), the arched dotted line over the group 3 is an error, and should be omitted.

GEOL.MAG.1878. New SERIES. DECADE Il. VOL-V. PLATE VI. ~

) r
sore x book xt /
=) =

CL.Griesbach lith. q W. West & Co tmp

Fig? 1%2. Preeatya scabrosa, H. Woodw.
Lower Lias , Barrow-on- Soar.

JONG. 3. Atya scabra, Leach ( Recent) N. America.

THE

GEOLOGICAL MAGAZINE.

NEW SERIES. DECADE II. VOL. V.
No. VIL—JULY, 1878.

O22 EG EINVAL, ASE CaaS.

————

I.—On a New anp Unpescripep Macrovuran Decarop Orustacnay,
FRoM THE Lower Lias, Barrow-on-Soar, LEICESTERSHIRE, ETC.

By Henry Woopwarp, LL.D., F.R.S., F.G.S. ;
of the British Museum.
(PLATE VII.)

N my third Report “on the structure and classification of the
fossil Crustacea,” presented to the Geological Section of the
British Association, at their Meeting in Dundee,! 1867, I stated that
a new Crustacean had been obtained, in 1858, by Sir Philip Grey-
Egerton, Bart., M.P., F.R.S., from the Lower Lias of Barrow-on-
Soar, Leicestershire, by whose kindness it is now preserved in the
British Museum : and also that another specimen, from the Lower
Lias of Somersetshire, belonging evidently to the same species, had
subsequently been found by Mr. Charles Moore, F.G.S., at Bath.
The specimen from Barrow-on-Soar (the impression and counter-
part of which is contained in two blocks of Blue Lias Stone)
exhibits on the surface of the slabs, the entire carapace, the eye,
antennze, the five ambulatory thoracic feet; but in this specimen the
abdominal somites and caudal appendages are entirely wanting.
(See Pl. VII. Fig. 1.)

Mr. Moore’s specimen, though rather Jess well preserved, exhibits
the carapace with the antennz ; the walking limbs are displaced and
expose the thoracic apodemata to which the branchizw and the coxal
joint of each limb were attached. The six abdominal somites are
also seen, but the caudal plates are only very imperfectly preserved.
(See Plate VII. Fig. 2.)

The carapace of this Crustacean evidently was extremely thin and
much less chitinous than in the genera Ager and Peneus ; it was
therefore more easily destroyed or distorted. In Fig. 1, the crumpled
and wrinkled appearance of the carapace is well shown. In Fig. 2,
the test is less well preserved, but near the posterior border there
is evidence to show that the surface was finely granulated (not
punctated as represented by the artist in the Plate). The dorsal

1 See British Association Reports for 1867 (1868), p. 44.

2 The abdominal somites have been added by the artist in outline to Fig. 1,
Pl. VII. merely to indicate their normal position; they are wanting in this speci-
men, and although present in Mr. Moore’s Crustacean from Bath (Fig. 2. Pl. VII.)
they are displaced.

DECADE Il.— VOL, V.—NO. VII. 19

?

290 Dr. H. Woodward—On a New Lias Crustacean.

line of the carapace, as seen in profile in our specimens, was much
arched, and the anterior portion bends down to terminate in a short
and blunt rostrum.

The orbital fossa forms a deep hollow on either side of the blunt
rostrum giving insertion to the eye-peduncles; the bases of the
antenne take their rise from the outer border of the orbits.

The carapace is marked at its posterior margin by a double line
or raised border, and is somewhat roundly inflected mesially, to give
insertion to the abdominal somites; but it again expands roundly on
the postero-lateral border over the branchial region.

None of the usual divisional lines or prominences, marking the
regions of the carapace, are visible on this Crustacean, and, save a
small marginal ridge on the hepatic border, near the orbital fossa,
the carapace is otherwise quite plain.

Length of carapace 50 mm., depth from dorsal line 25 mm.

The antennules have slender multiarticulate flagella 15 mm. in
length. The antenne have three robust and very rugose basal
joints, 15 mm. long, succeeded by a stout but tapering many-jointed
flagellum nearly 25 mm. in length, reminding us of the stiff outer
antenne of Palinurus.

The thoracic limbs are stout and rugose, all their extremities are
monodactylous. The first pair is the most robust, the second is
nearly equal in size to the first ; the third and fourth pairs are more
slender and nearly as long; the fifth pair is much the smallest.

I subjoin the measurement of the five thoracic limbs in millimétres.

Limbs of thorax........0cs:ssesvcoscsrorenss 1 II. III. IV. Y.
Ist joint Or COxa ........ccoccsscevereoncnss 3? 3 3 3 2
Ding) 9) Go BRIS Ganccobssooode06aR000 00d00 4? 4 4 4 2
SUC Gis wimels chil uemenctererescecscsee et 7 6 7 4 4
ATTN em ENUCTOSoctecsiccteacccescssecter cine 13 12 9 8 7
GUN op | CERRO cococqcas5pa900cEc003000 6 5 5 5 5
Give ee RODOCOSueterscrscmssece dace ss 6 6 8 9 7
iLL EL AC LATS eee tocetwanecesticasicas 7 6 5 5 5

Total length .......seccscseees 46 42 41 38 82

The figures of the fossil drawn in the Plate do not sufficiently
show the rugosity of the limbs, which is a strongly-marked character
in the fossil. The abdominal somites are preserved more or less
perfectly in Mr. Charles Moore’s specimen (Fig. 2). ‘Their breadth
is about 7 mm. each, and extreme depth of profile of segment 19
mm.; the epimeral border of the segments is lanceolate. The
segments were finely granulated on their margins. The caudal
plates appear to have been broadly rounded in outline, but they
are too imperfect to describe minutely.

Total length of abdomen 55 mm.

In most of our common living Macroura, the first and second pairs
of thoracic appendages resemble the last pair of the cephalic series,
being maxillipeds, or mouth-organs. The third pair are usually the
largest of the series, and are mostly chelate (serving as hands), the four
remaining pairs being commonly employed as the ambulatory legs.

In the fossil before us neither the third pair, nor the four pairs of

Mr. O. Fisher—Changes of Latitude on the Earth’s Surface. 291

limbs succeeding it, are chelate, all the five pairs of legs being
monodactylous, as in Palinurus, Scyllarus, and Thenus: but in this
division the carapace and the abdominal segments are not arched,
but expanded laterally ; whilst this Lias Crustacean, like the Astacide,
Palemonide, etc., has the carapace compressed laterally, and the
segments of the abdomen are not flattened, but are well arched.
The antennules are not like those of Palinurus, which have a few
long articuli, but are multiarticulate like those of the Astacide and
Palemonide.

From a careful comparison, made in 1867, of its general characters,
I was led to consider the fossil before us as probably most near to
the recent genus Atya of Leach, from South! America, and I then
proposed to name it Preatya scabrosa, but in all the recent species
of the genus Atya the third and fourth pairs of thoracic appendages
are modified so as to subserve, like the first and second pairs, rather
the office of maxillipeds or mouth-organs than of feet ; the fifth,
sixth, and seventh pairs alone remaining as simple monodactylous
ambulatory legs. Whether this modification of the third and fourth
pairs of thoracic appendages in the genus Atya has taken place
since Liassic times, and so the fossil form be really ancestrally
related to that modern crustacean, can only be a matter of con- -
jecture, but bearing in mind this important difference in the modifi-
cation of the thoracic limbs, they have nevertheless still many
points of resemblance. I have therefore retained the original name
Preatya (conferred upon it in 1867), and by that appellation I
now beg leave to introduce it to paleontologists and especially to
those who are interested in Liassic fossils.

EXpLaNnaTion oF Pruate VII.

Fig. 1. Preatya scabrosa, H. Woodw., Lower Lias, Barrow-on-Soar (drawn nat.
size). The original specimen in the British Museum.
» 2. Preatya scabrosa, H. Woodw., Lower Lias, Bath. The original specimen
in the Collection of Charles Moore, Esq., F.G.S., of Bath.
» 8. Outline of Atya scabra, Leach (recent), South America.

I].—On tHE Possrpinity or CHANGES IN THE LaTITUDES oF
Puaces ON THE Harru’s SURFACE; BEING AN APPEAL TO
PHYSICISTS.

By O. Fisuer, Clk., M.A., F.G.S.

\ R. HILL’S paper in the June Number of the Magazine has

incited me to recur to the great question of the possibility
of changes in the earth’s axis of rotation within itself. Mr. Hill is
well known to be an accomplished geologist ; but he writes as if he
were simply a physicist, without sympathies for the difficulties of
his brethren of the hammer. Yet we feel certain that such is not
the case. We know that he has studied in the field the tremendous
movements which the strata have undergone, being often compressed
into a small part of their original length: that he has appreciated
the almost ubiquitous presence, either in past or present time, of
voleanic activity: that he must feel how unsatisfactory all explana-

1 Incorrectly marked as N. America on the Plate.

292 Mr. O. Fisher—Changes of Latitude on the Earth’s Surface.

tions short of a change in latitude are to account for the flora of a
warm climate within the arctic circle. We therefore appeal to him,
and to others similarly qualified, to look at this subject from both
sides.

Dr. John Evans, in a paper which he read before the Royal
Society in 1866,' suggested a cause why, in his opinion, a moun-
tainous region, newly upheaved above the general surface of the
earth, would have a tendency to travel towards the equator, mov-
ing the rest of the crust along with it. “My hypothesis,” he said
ten years later, in his Presidential Address of 1876, “ was founded
on the assumption of the globe consisting of a comparatively thin
crust with an internal fluid nucleus, over which the crust could
slide when from any geological cause its equilibrium was dis-
turbed.”* But the hypothesis under which he then appealed to
physicists for a solution of the question, if not intended by him
to be different from the above, has, at any rate, been so taken by
Mr. Twisden,* and Mr. G. Darwin,' and, following them, by Mr. Hill;
for all these gentlemen have supposed the globe solid from the
surface to the centre. I do not think that any geologist can easily
entertain this opinion ; and when, in handling the subject, one omits
all reference to any other possible supposition as to the state of the
earth’s interior, it seems to me that he is not rendering that help to
his less accomplished brethren which he might render.

The causes, which lead physicists to regard the problem from their
point of view, may partly be, first, that the great problem of Pre-
cession and Nutation has always been so treated. They are, there-
fore, already some way on their road towards the elucidation of any
other question of this class. Secondly, the perhaps greatest living
physicist in this kingdom has pronounced in the strongest language
against the doctrine of a fluid interior. He appears, in consequence
of a conversation with Professor Newcomb, to have given up the
original argument against it from precession and nutation. ‘ Inter-
esting in a dynamical point of view as Hopkins’ problem is, it cannot
afford a decisive argument against the earth’s interior liquidity.” *
But there remain the tides. ‘The solid crust would yield so freely to
the deforming influence of the sun and moon, that it would simply
carry the waters of the ocean up and down with it, and there would
be no sensible tidal rise and fall of water relatively to land.”® I
have inquired’ whether, taking their lagging into consideration, it is
certain that the crests of the tidal waves in the ocean and in the
crust would occur simultaneously at the same place: because, unless
they did so, we might still have a tide relatively to land. Recently,
at the Cambridge Philosophical Society, when Mr. Hill gave some
illustrations corroborative of Mr. G. Darwin’s results, Mr. Darwin
told the meeting, in reply to some remarks of mine, that he had

1 Proc. Roy. Soc. No. 82, 1866.

2 Quart. Journ. Geol. Soc., vol. xxxii. Presidential Hadras! p. 108.

3 Quart. Journ. Geol. Soc., ’ vol. xxxiv. p. 36.

4 Trans. Royal Soe. vol. 167, p art i.

5 Sir W. Thomson’s Sectional “Adaress Nature, vol. xiv. 1876, p. 429, 2nd column.
6 Thid. 7 Quart. Journ. Geol. Soc., 1875, p. 470.

Mr. O. Fisher—Ohanges of Latitude on the Earth’s Surface. 2938

been investigating the above question raised by me. We may, there-
ore, hope to receive a decisive answer to it.

It does not, however, appear necessary that geologists should be
concerned to inquire whether the earth is wholly fluid within. If
there be granted a layer of fluid matter of a thickness even very
small compared to the radius of the earth, that will suffice us.
May not the argument for rigidity drawn from the tides, after it
has received that definite weight which proper observations (yet
to be made) are expected to give it, be satisfied with a rigid
nucleus of radius nearly approaching to that of the entire globe?
Such tides as would be formed within the liquid substratum of
the crust would not be of the nature of the tides, contemplated
by Sir W. Thomson as affecting the entire spheroid, but more
nearly analogous to the ocean tides; since they would involve a
horizontal transference of fluid backwards and forwards, and might
be expected to be of small amplitude, owing to the viscosity of the
substance and its confinement beneath the crust. However, even
the modest requirement of a fluid substratum is denied to us.
« But now thrice to slay the slain. Suppose the earth this moment
to be a thin crust of rock or metal resting on liquid matter. Its
equilibrium would be unstable! And what of the upheavals and
subsidences? They would be strikingly analogous to those of a
ship that had been rammed; one portion of crust up and another
down, and then all down. I may say with almost perfect certainty
that whatever may be the relative densities of rock, solid or melted,
at or about the temperature of liquefaction, it is, I think, quite cer-
tain that cold and solid rock is denser than hot melted rock, and no
possible degree of rigidity in the crust could prevent it from break-
ing in pieces and sinking wholly below the liquid lava.”

If we now turn to Mr. Hopkins’ Researches in Physical Geology,’
we find that he had gone into this question somewhat fully, and
held an exactly opposite opinion from the above. He considered
that, so long as the matter of the earth retained a sufficiently high
state of fluidity to admit of the circulation of convection currents,
no crust could form : but that when, by those means, the temperature
had been so far reduced that convection became arrested, immediately
a crust would be formed. “Since the heat increases with the dis-
tance from the surface, while the mass is cooling by circulation, the
tendency to solidification, so far as it depends on this cause, will be
greatest at the surface, and least at the centre. But on the other
hand, the pressure is least at the surface, and greatest at the centre ;
and consequently the tendency to solidify as depending on this
cause will be greatest at the centre, and least at the surface.” For
want of experimental evidence, “the only conclusion at which we
can arrive is this, that if the augmentation of temperature with that
of the depth be so rapid that its effect in resisting the tendency to
solidify be greater than that of the increase of pressure to promote
it, there will be the greatest tendency to become imperfectly fluid,

' Trans. Roy. Soc. part ii. 1839, quoted in his Report to the British Association,
1848.

294 Mr. O. Fisher—Changes of Latitude on the Earth’s Surface.

and afterwards to solidify, in the superficial portions of the mass:
whereas, if the effect of the augmentation of pressure predominate
over that of temperature, this transition from perfect to imperfect
fluidity, and consequent solidity, will commence at the centre.”

Assuming the latter to be the case, when the mass should have
arrived at that stage of cooling that “a solid nucleus had been
formed, surrounded by an external portion of which the fluidity
would vary continuously from the solidity of the nucleus to the
fluidity of the surface, where, at the instant we are speaking Olena
would be just such as not to admit of circulation; . . . a change
would take place in the process of solidification which it is important
to remark. The superficial parts of the mass must in all cases cool
the most rapidly, and now (in consequence of the imperfect fluidity)
being no longer able to descend, a crust will be formed on the
surface, from which the process of solidification will proceed far
more rapidly downwards, than upwards on the solid nucleus.” And
in a note to the Report,! he writes thus decidedly: ‘Supposing the
earth once to have been fluid, it must be now, or have been at some
antecedent epoch, in that state in which a solid exterior rests on an
imperfectly fluid and incandescent mass beneath. It is important
to know that this state of the earth, assuming its original fluidity,
is one through which it must necessarily have passed in the course
of its refrigeration, whatever might be the process of its solidifi-
cation.”

These remarks of Mr. Hopkins deserve serious consideration,
and are not lightly to be set aside. They are entirely independent
of his subsequent calculations by which he considered he had proved
(and was until very lately indeed considered by the greatest mathe-
maticians to have proved)? that this crust was not at the present
time a thin one, but had grown to the thickness of at least not far
short of a thousand miles; even if its downward growth had not
already met the upward growth of the solid central nucleus.

The reasoning by which Mr. Hopkins concluded that a crust
would form (and he clearly supposed it would be supported also),
seems to be assailable only on the supposition that upon solidifi-
cation a sudden considerable contraction, and consequent increase of
density, would occur, which would enable the fragments to sink
in a fluid, too viscous to admit of the sinking of portions cooled to
the verge of solidification.

It is practically seen that a crust can be formed and supported
upon liquid lava by what is known to happen in the crater of
Kilauea. This is of an elliptical form, three miles in its longer
diameter: consequently the attachment to the cliff-like sides can
have little effect in supporting the crust over so large an area.
Moreover, this has been observed to rise and sink with variations
in the level of the lava, showing that it really rests upon the fluid
support. ‘The floor of the pit is described as usually presenting
a crust over a vast pool of lava, which is from time time broken
through by a fresh upboiling of the incandescent mass beneath.

1 Page 48. 2 Vide supra, p. 292.

Mr. O. Fisher—Changes of Latitude on the Earth's Surface. 295

It cools and hardens so rapidly on exposure, that it may be walked
upon within a few hours after coagulating. Sometimes upwards
of fifty small cones and craters, more or less in activity, have been
counted on the floor of this great pit. They were from fifty to
a hundred feet high.”! “It is nine miles in circumference, and its
lower area, which not long ago fell about 300 feet, just as ice on
a pond falls when the water below it is withdrawn, covers six
square miles.”? In the case of the earth’s crust, it seems probable
that the lateral pressure, to which the upheavals and subsidences
are due, would have the effect of keeping the fragments of the crust
close pressed together, and so checking anything like a general
intrusion of lava between them. Its exit would probably be con-
fined to here and there volcanic vents, more numerous, no doubt,
and larger, in ancient times, but still in general character like those
of the present day.

The argument for the existence of a fluid layer beneath the
present crust appears to me to be considerably strengthened by
a comparison which I have myself made between the actual in-
equalities of the earth’s surface and those which could have been
formed by lateral pressure if the globe had cooled as a solid body.*
This has led me to the conclusion that some condition has been
present which has admitted of its shrinking much more than it
could have done if it had cooled as a solid; nay, probably more
than mere cooling alone can account for. I surmise therefore that
the interior has contained water, which has escaped through volcanic
vents as superheated steam, and that the earth’s volume has been
diminished in that manner by the actual transference of matter
from beneath to above the crust. What may be the exact amount
of decrease of volume which might be obtained by transferring
a given quantity of water from beneath to above the crust, it is not
possible to say; because we do not know the properties of water
as it may exist under such circumstances of heat, pressure, and
chemical combination as obtain within the earth. But it is obvious
that a larger contraction can be accounted for by aid of this supposi-
tion than without it. I received a letter from Mr. Scrope in October,
1876, very shortly before his death, in which he commented on this
suggestion. “There is one of the points you put forward which never
struck me before, but which now appears to me most valuable ;
viz., that the enormous amount of steam that has escaped from the
interior in early times, as well as down to the present, has been, and
is, the cause of those subsidences of the crust, to which the basins of
seas and oceans, and the crumplings of the terrestrial rocks are owing,
far more than to any general contraction of the nucleus by cooling.”

It is known also that mountain chains have most of them been
ridged up and folded much more than the country bordering upon
them. Now this peculiarity implies a slip of the superficial strata

1 Serope’s Volcanos, p. 477, ed. 1862.

2 Miss Birt’s Hawaiian Archipelago. See Nature, vol. xi. p. 324.

% Trans. Cambridge Phil. Soc., vol. xii. part ii., abstracted in Gzon. Mae. N.S.
Vol. I. p. 60.

296 Mr. O. Fisher—Changes of Latitude on the Earth’s Surface.

over whatever it be that underlies them. It is obvious that a more
or less perfectly fluid substratum is required to give this capability
of slipping. Indeed the nearest analogy to the formation of a chain
of mountains seems to be found in the crushing together of the
adjacent edges of two sheets of floating ice.

I have thus, I think, shown that the supposition of a liquid
layer beneath the crust of the earth is not a supposition that
is so wholly untenable as has been represented, and that, as far
as authority (that blind guide) can determine the question, we
have it on both sides. I recur therefore to my original proposition,
that physicists should be moved to consider what elements of
change in the position of the earth’s crust as regards latitudes
might be introduced under the influences acting upon it, by the
existence of a considerable degree of mobility between the crust
and a solid nucleus owing to the intervention of a liquid stratum.
The solidity of the crust being supposed due to cooling, and that
of the nucleus to pressure, I would consider the crust thin, and the
fluid substratum also thin. I would consider the crust and the
fluid of sensibly the same thicknesses at the equator as elsewhere,
taking the equatorial bulge as existing in the solid nucleus. This
supposition would seem admissible, because we have volcanos in
low as well as in high latitudes, showing that, if they be connected
with a liquid substratum, that cannot be much more deep down in the
one region than in the other. Moreover, the ratio of the centrifugal
force to gravity being small, it is not likely that the upper linit
of the pressure necessary to induce solidity should be at an ap-
preciably greater depth below the surface at the equator than at the
poles. I would consider the crust flexible, but for the purposes of
the problem not horizontally compressible further than would allow
it to fit the spheroid in any new position so that it should move all
together. Then I would inquire, a portion of it having become
thickened by assemblages of foldings near together, in other words
by the elevation of continents, what effect these would have -upon
the position of the crust as regards the axis of rotation of the
whole, supposed fixed in space.

This is, in short, Dr. Evans’s original problem, which he en-
deavoured to solve by experimental means.

But the question I would put is, whether, supposing the crust
free to move under forces as small as those which this change of
form would bring to bear upon it, the effect would be (not that
the protuberances would be brought towards the equator, as in Dr.
Evans’s wheel), but that the crust would tend to be carried into
such a position that the axis of symmetry of the solid nucleus and
of the crust together (i.e. their axis of greatest moment of inertia)
would tend to coincide with the axis of rotation. If this were
so, the nucleus being spheroidal, the crust would eventually become
so placed with regard to the axis of rotation that that would
coincide with its axis of principal moment of inertia. If, how-
ever, the crust were free to obey this tendency only to a certain
degree, being checked, partly by the rigidity of its parts not

Rk. F. Tomes—Corals of Crickley Hill. 297

allowing it to adapt itself freely to its altered position on the
spheroid, partly by the viscosity of the liquid, and partly by
decrease in the moment of the forces shifting it; then, the crust
having progressed as far as it was permitted to do, would stick
fast, and the whole would commence to rotate as a solid body, and
the principal axis, being that neither of the crust alone, nor of the
solid nucleus alone, but of the whole mass, would come to coincide
with the axis of rotation.

Now when I look at the distribution of land on the globe, and
observe it chiefly confined to one hemisphere, and arranged in a
manner, not symmetrical, but with an approach to symmetry as
regards moment of inertia about the axis of rotation, I fancy I see
an indication of the truth of the supposition advanced.

It is possible that a future generation of geologists may be able to
gather some information regarding the interior of the earth from the
mysterious phenomena of magnetic variation. But at present we
cannot hope for much help from this quarter. The temptation,
however, is too great to forbear quoting from Captain Evans’s lecture
a very striking passage.! ‘ These are a few facts relating to secular
changes going on in two magnetic elements within our own time ;
and what are the inferences to be drawn therefrom? They appear
to me to lead to the conclusion that movements, certainly beyond our
present conception, are going on in the interior of the earth; and
that so far as the evidence presents itself, secular changes are due
to these movements, and not to external causes. We are thus led
back to Halley’s conception of an internal nucleus or inner globe,
itself a magnet, rotating within the outer magnetised shell of the
earth.” This is, to say the least, in very remarkable accordance with
the conclusion I have proposed to draw from geological and other
considerations.

IIJ.—A List or rot Mapreporaria OF CrIcKLEY Hit, GLOUCESTER-
SHIRE, WITH DESCRIPTIONS oF somME NEw SPECIES.

By Rozert F. Toms, F.G.S., Corr. M.Z.S.

A CONSIDERABLE part of the material forming the present
communication was collected as long ago as 1862, but the
specimens obtained at that time, with the notes thereon, remained in
abeyance until quite recently. On a renewed examination of them,
it appeared that much of what had been noted down had not been
superseded, and this induced me to go through the whole of it
again, and make such additions and modifications as seemed necessary
to bring it into its present form. And I have done this in the hope,
and indeed in the belief, that it will serve a twofold purpose. It
will make known some forms which are new, not only to the
particular locality, but also to the catalogue of English species ;
and it will furnish a more complete list than has yet appeared of the
species from one of the best-known Coral-reefs of the Inferior Oolite.
The Crickley Coral-reef, according to Dr. Wright, is the lowest of

1 Lecture at the Royal Geographical Society, March 11, by Capt. F. J. Evans,
C.B., F.R.S., Hydrographer to the Admiralty, Nature, May 16, 1878.

298 R. F. Tomes—Corals of Crickley Hill.

three which are found in the Inferior Oolite of the Gloucestershire
Hills, and it rests on the Pisolite or Pea-grit.

I can hardly expect that the following list comprehends anything
like all the species which occur at Crickley: most likely it does not
even include all those which have been collected, and are known ;
but it is more ample than any one which has yet been published,
and may serve as a basis to which additions and corrections may
from time to time be made. All the specimens to which J shall refer
were collected by the Rev. P. B. Brodie, F.G.S., Mr. J. W. Kirshaw,
F.G.S., and myself, during a very few visits made by us to that
locality. Many of the species were found in siti; but some of them,
though of unquestionable authenticity as far as the locality is con-
cerned, cannot be placed stratigraphically, having been found
amongst the weathered débris on the slopes beneath the section.
All are referable to two families, the Astreide and the Fungide.

Family AsTREIDz.
Montitvattra Hox, Duncan, Supp. Brit. Foss. Cor., pt. iii. p. 16,
pl. 1, fig. 5-6.

Two examples only of this species have been taken.directly from
the Coral-bed by myself, when they were associated with the follow-
ing species, Monitlivaltia Painswicki. Both of them exhibit the
calicular peculiarities mentioned by Prof. Duncan, but externally they
differ not only from his figure, but also from each other. They are
attached to a worn piece of a Thamnastrea, and are very crooked
and rugose. They have much the appearance of springing from one
root, and their general aspect is very suggestive of some species
of Thecosmilia. In both specimens the margins of the septa are
entire and quite smooth.

Monriivaut1a Patnswick1, Duncan, Supp. Brit. Foss. Corals, pt. 3,
jos WE, fall, A, atleg, Net

Of this species several examples were found associated with the
foregoing in the Coral-bed, and all of them possess the characters
attributed to this species by Prof. Duncan. They vary a little, chiefly
in not being equally compressed, but in every instance the calice is
more or less irregularly ovoid, with a slight tendency towards a
lobular outline, and a narrow linear base. In all of them the
principal septa meet and unite in the centre of the calice, but without
forming the least indication of a columella.

MontiivaLt1a TROcHOIDES, Hdw. and Haime, Ann. des Sci. Nat. s. 3,
vol. x. p. 229 (1848); Brit. Foss. Cor. pt. ii. p. 129, pl. xxvii.
figs. 2-4.

All the varieties figured by MM. Edwards and Haime in their
History of British Fossil Corals have been met with at Crickley.
Most of the specimens I have seen have lost their epitheca, and have
been otherwise rubbed and damaged.

MonrtitvatiaA LENS, Edw. and Haime, Hist. Brit. Foss. Cor. pt. ii.
p- 138, pl. xxvi. figs. 7 and 8.

Previously to 1862 I had received many examples of this species,
some of which were said to have been obtained from Crickley, but

R. F. Tomes—Corals of Crickley Hill. 299

they were unaccompanied by any information respecting the particular
bed from which they were taken. However, in that year I took two
examples from the Cephalopoda bed at that place, and I have no
doubt, from the similarity of the matrix in all of them, that they had
been derived from the same bed. At Dover’s Hill, near Chipping
Campden, the species was found abundantly a few years since in a
layer of soft rufous sandstone underlying the Cephalopoda bed. It
was at this place associated with another species of Montlivaltia and
a species of Thamnastrea.

CYATHOPHYLLIA OOLITICA, n.S.

The genus Cyathophyllia was established by M. de Fromentel’
for a species of Coral from the upper beds of the Middle Lias of
Normandy. It resembles the genus Monitlivaltia, excepting that it
has a large papillated columella. Since the appearance of the de-
scription of the genus by M. de Fromentel, Dr. EH. A. Reuss? has added
another species to it, in a paper on the Miocene Corals of Hungary.
By means of the excellent figures and descriptions furnished by these
authorities, I have been enabled to determine a much worn coral
from Crickley, and add another species to the genus, which I de-
scribe thus.

The corallum has a much depressed turbinate form. The calice
is sub-ovoid, slightly convex, with a sub-central shallow fossula,
which is filled by a large oblong and papillated columella. The
septa are numerous, about 160 in number ; they are straight, pretty
uniform in thickness, and about 50 pass into the columella. There
is considerable irregularity in the degree of development of the
newer cycles of septa. The columella is porous and papillose, and
the processes of which it is composed are curved and twisted, some-
what as they are in the Parasmilie. It is oblong in the direction of
the greatest diameter of the calice, of which it is one-fifth of the
length.

The margins of the septa have been worn off, but their connexion
with the columella is very clearly shown. The epitheca appears to
have deen destroyed, and the costa exhibit between them well-
marked and rather numerous dissepiments.

Height of the corallum 4 inch; diameter of the calice 1# inch.

THECOSMILIA GREGARIA, M‘Coy, sp. Monilivaltia gregaria, M‘Coy,
Ann. & Mag. N. H. ser. 2, vol. ii., p. 119 (1848).

All the specimens I have examined have been found amongst the
rubbish which, having fallen from its proper bedding, had become
weathered. It is a most variable species, ranging from a branching
to a compact coral. Prof. Duncan observes of it: “A careful study
of the Thecosmilia of the Inferior Oolite at Crickley has enabled me
to distinguish five very remarkable varieties of Thecosmilia gregaria,”
and again he remarks: “There are specimens of Thecosmilia gre-
garia in Dr. Wright’s collection, which, had I not had a consider-
able series to examine from other sources, might have been associated

1 Pal. Franc. Coral. Terr. Juras. p. 86, pl. 18, f. 1.
2 Sitzung. Math. Naturw. Akad. Wiss. lxi. Bd. 1, Ab. 37, Taf. iv. f. 1 (1870).

300 Rk. F. Tomes—Corals of Crickley Hill.

with Reuss’s new genus, Heterogyra, together with Symphyllia and
Latimeandra.”}

I think, however, that, variable as this species may be, some of the
so-called varieties will eventually prove to be distinct. When all
the young forms of these several varieties have been recognized,
and a full series of examples of different ages have been compared
and their successive growth traced out, it is more than probable that
their distinctive characters will assume a more definite form.

TxEcosmitta Wrieutt, Dunc., Supp. Brit. Cor. pt. iii. p. 17, pl. v.
figs. 1, 2, 3, 4 (1872).

Many fragments of this species occur in the Coral-bed at Crickley,
but none that I have met with have been sufficiently perfect to give
any indication of the height attained by the corallum, but their
straightness and the unfrequency of forked pieces may be taken as
suggestive of a tall species. The straightness and parallel arrange-
ment of the branches in Prof. Duncan’s figure would seem to point
to the same conclusion.

TuEcosMiLt1a RaMosa, d’Orbig., Prodr. de Paleont. t. i. p. 292. (1850).
A small species of this genus, of which I have as yet seen but one

specimen, appears to resembie the T. ramosa of M. d’Orbigny in

the size of its calices, and in having four cycles of unequal septa.

To the very brief description of M. d’Orbigny I add the
following :—

Corallites free, much curved, and enlarging slowly. They are
very rugose, and each one is incased in a thick epitheca, strongly
marked with concentric folds and wrinkles.

Walls thick, calices round, but becoming ovoid before dividing
into two. Septa irregular. The first and second cycles meeting in
the centre of the calice, thicken and unite and form an irregular
but rather large columella.

Height of the corallites from one to two inches, diameter of the
calices three to four lines.

It was obtained from the Crickley Coral-zone by my friend Mr.
J. W. Kirshaw, F.G.S8., and kindly given by him to me.

IsASTRHA TENUISTRIATA, Edw. and Haime, Brit. Foss. Cor. pt. ii.
p- 188, pl. xxx. fig. 1; Hist. Nat. des Coral. tom. ii. p. 582;
EK. de From. Etude Polyp. Foss. p. 226.

ASTREA TENUISTRIATA, M‘Coy, Ann. & Mag. Nat. Hist. ser. 2, vol. il.
p. 400 (1848).

Of this rather remarkable species I have up to the present time
only made a superficial examination, but I am led to suspect, from
the appearance of some of the calices, that more intimate research
would reveal characters not wholly those of typical Isastree. On
some parts of the calicular surface a distinct flat depressed space is
visible between the calices, over which the septa (coste ?) pass, and
unite with those of contiguous calices. This species appears, as far
as conclusions may be drawn from external appearances only, to
hold some affinity with the genus Confusastrea.

1 Supp. Brit. Fos. Cor. pt. iii. p. 2, 1872.

R. F. Tomes—Corals of Crickley Hill. 301

TsASTR#A EXPANSA, N.S.

Many fraements of a very thin and expanded species of Isastrea
were taken by myself at Crickley before I succeeded in obtaining a
sufficiently perfect specimen for description. By carrying away
some large lumps of the soft cream-coloured Coral-bed, and ex-
tracting with care the corals contained in them, I obtained good
examples of many of the species mentioned in this paper, and
amongst them a series of the species which I now describe under
the above name.

Corallum consisting of a thin irregular horizontal plate supported
on a sub-central peduncle. The upper or calicular surface is undu-
lating and has a very thin outer margin. The peduncle is short,
irregular in form, and very rugose. Both it and the inferior surface
of the expanded part of the corallum have a well-developed epitheca,
which is strongly marked with concentric folds or ridges.

The calices over the peduncle are somewhat hexagonal, but as
they approach the outer boundary of the corallum they assume a
somewhat rounded, ovoid, or lozenge shape, their greatest diameter
being in the direction of their progressive growth, that is, from the
centre towards the circumference of the corallum. They are rather
superficial, and the intercalicular or mural species consist of thick
rounded ridges, constituting the walls.

The septa are about 33 in number, and form four cycla, of which
the fourth is incomplete. Those of the first and second cycla
approach nearly to the centre of the visceral cavity and have their
inner extremities thickened sufficiently to give something the ap-
pearance of a coronet of pali. The septa of the third cycle are
about two-thirds of the length of those of the first and second, and
those of the fourth are quite short. All of them have a rounded
superior margin and a granulated surface, and they are continued
over the top of the tumid walls and are continuous with those of
contiguous calices.

Diameter of the calices 14 to 2 lines.

The general form of this species is sufficient to distinguish it from
all other British species of Isastrea. 'The form too of the calices is
distinctive, more especially in the worn examples, in which the
thick walls are most visible. In these the calices are seen to have
but little angularity, but resemble shallow cups having a pretty
regularly rounded or ovoid form.

The species to whichit bears the greatest resemblance by the
structure of its calices and walls is the Isastrea foliacea of
M. de Fromentel, from which however it is specifically quite distinct.

LatTImMmANDRA F'Leminer, Edw. and Haime, Brit. Foss. Cor., pt. 1.
p. 186, pl. xxvii. f. 9.
Examples of this species are not rare at Crickley, and some of them
exhibit a peculiarity which is not common in the Oolitic Isastree.
The near connexion of the genus Latimceandra with the genus
Isastrea has been noticed by MM. Edwards and Haime in their
History of British Fossil Corals (part 11. p. 187), and again in their

302 R. F. Tomes—Corals of Crickley Hill.

Histoire Naturelle des Coralliaires (tome ii. p. 548). In the latter
work they observe: ‘Ce groupe est trés-voisin des Isastrées: il
s’en distingue par Vabsence d’épitheque et la tendance de ses poly-
perites 4 former des séries plus ou moins longues.”

Prof. Duncan, in his Supplement to the History of British Fossil
Corals (part iii. p. 18), observes of this species: “Many portions of
the corallum do not present serial calices, and if such fragments
were found separate, they would necessarily be associated with the
genus Isastrea.”

Neither of these paleontologists, nor yet M. de Fromentel, appear
to have observed a peculiarity which is seen in some specimens of
Latimeandra Flemingi from Crickley, and that is, the total absence
of a common or enclosing wall, and the consequently exposed and
open condition of the inferior extremities of the corallites. This
is not a common character amongst the Oolitic Isastree, though it
prevails amongst the Liassic species.

CLAUSASTRHA CONSOBRINA ? Kd. and Haime.
Pal. Foss. des terr. Paleon. p. 107 (1851). Hist. Nat. Cor. tom. ii.
p- 552 (1857).
KE. de From., Intro. Etud. Pol. Fos. p. 281 (1858-61).
Synastrea consobrina, d’Orb., Prod. de Pal. Frane. t. i. p. 293 (1850).

I have seen one specimen only of a coral which I refer with some
doubt to the above species. It was taken from the Coral-bed by
myself in 1862. It agrees so closely with the description given
by MM. Edwards and Haime of Clausastrea consobrina, as well as
with that of M. de Fromentel, that I have referred it to that species,
though with some doubt.

The corallum has the thin and expanded form so common amongst
the Crickley corals. The calices, though superficial, are symmetrically
round, and the septa somewhat exsert, with a small but well-
defined circular fossula. The septo-costal rays are continuous in
adjacent calices, though not as in the genus Thamnastrea, but
often meeting and uniting at an angle on the mural region. The
walls are either wholly wanting or merely rudimentary, and the
dissepiments are well developed and domeshaped.

M. de Fromentel places the genus Clausasirea amongst the
Zoantharia Tabulata on account of the dissepiments taking the
position of tabule. In my specimen, though they are on nearly
the same planes, they preserve the character of true dissepiments,
and can scarcely be said to form tabulee.

Family Funem2.

Genus Tuercoseris, H. de From.

M. de Fromentel thus characterizes this genus. Corallum elevated
and regularly turbinate. Calicular fossa, when it exists, round.
Most commonly the septa are united in the centre of the calice, and
form a false columella. They are fine, numerous, often anasto-
mozing, and finally denticulated. They are never exsert, and the
calice is generally concave. The epitheca is strong, well developed,
in folds, and reaching to the margin of the calice.

R. F. Tomes—Corals of Crickley Hill. 303

The type is T. patellata, E. de From. et'Fery, Paleont. Franc.
Terr. Juras. pl. 58, fig. 2 (1869). From the Middle Lias.

The description of the genus appears in the Paleont. Franc. Terr.
Crétacée, p. 367.

THECOSERIS POLYMORPHA, 0.8.

Corallum simple, variable in form, but always more or less tur-
binate, and non-attached.

The wall is thin, its superior margin prominent, undulating and
sometimes almost foliaceous.

Coste, when exposed by abrasion of the epitheca, numerous,
delicate, and with lateral synapticulz feebly developed.

Epitheca thick, rugose, and exhibiting distinct rings of growth.

Calice shallow, concave, and extremely variable in outline. Fossula
small, but round and well defined.

Septa rather numerous, somewhat flexuous, irregular in thickness,
and not diminishing as they approach the calicular fossula. Those
of the younger cycles pass into those of the older ones.

Synapticule feebly developed.

Height of the corallum 4 to 1} inches. Diameter of the calice 1
to 14 inches. This appears to be a common species in the Coral-
bed at Crickley.

The genus Thecoseris appears to be nearly related to Trochoseris,
but differs most essentially from it in having no columella. In this
respect it resembles the genus Turbinoseris as defined by Prof. Duncan.!
In the only example appertaining to this latter genus which I have
been able to examine (a specimen of Turbinoseris De Fromenteli,
Duncan, from the Lower Greensand of Atherfield), the calice is a
little convex with a slightly everted margin, and with a shallow
round fossula. It bears very considerable resemblance to some
examples with unworn calices, of Podoseris mamilliformis, Duncan,
from the Red Chalk of Hunstanton,” but it differs essentially in not
having any epitheca. The Podoseris mamilliformis is a particularly
variable species, as far as form is concerned, many specimens having
a turbinate form with a depressed calice, and a small but weil-
marked central fossula. Yet all which I have examined (in number
considerably more than a hundred) have had a well-defined epitheca.
But the existence of an epitheca in this species is rendered less im-
portant in a generic point of view by the feeble degree of its develop-
ment in another species described by Dr. Duncan from the Oolite of
Dorsetshire, under the name of Podoseris constricta.2 Besides the
want of a well-developed epitheca, this species further departs from
the original definition of the genus Podoseris by having a small
instead of a large base. These peculiarities help to bring Podoseris
in nearer relationship with Turbinoseris; and with a more ample
list of species representing the genera Thecoseris, Podoseris, and
Turbinoseris, it is quite probable that they may require reconsidera-
tion.

1 Supp. Brit. Fos. Cor. pt. ii. No. 2, p. 42 (1870).

2 Supp. Brit. Fos. Cor. pt. ii. No. 1, p. 25 (1869).
3 Supp. Brit. Fos. Cor, pt. iii. p, 24 (1872).

304 R. F. Tomes—Corals of Crickley Hill.

THAMNASTRHA Derrancrana, Edw. et Haime, Pol. des Terr. Paleon.
p. 110 (1851) ; Brit. Foss. Corals, pt. ii. p. 139, pl. 29, fig. 3
and 4; Hist. Nat. Coral. tom. ii. p. 561. Astrea Defranciana,
Mich. Icon. p. 9, pl. 2, fig. 1 (1840).

In Michelin’s figure the calices are more concentrically arranged

than in any example I have met with. This appears to be a

common species at Orickley.

THAMNASTRHA TERQUEMI, Hdw. et Haime, Pal. des Terr. Paleon.
p. 110 (1851) ; Brit. Foss. Coral, pt. ii. p. 140, pl. xxx. fig. 2;
Hist. Nat. Coral. tom. ii. p. 579.

In most of the species from Crickley the basal portion is much
less symmetrical than in the figure given by Edwards and Haime
in their History of British Fossil Corals. In many examples the
epitheca is gone, and the whole of the inferior part of the corallum
has a more or less lobular form, and the outline of the calicular
surface has a corresponding degree of irregularity in its outline.

ToamnastR#A Mertrensis, Edw. and Haime, Brit. Foss. Corals,
pt. ii. p. 141, pl. xxx. fig. 3; EH. de From., Introd. 4 ?Htude
J2Olk (os “ilés

This appears to be abundant at Crickley.

Tuamnastrma Lyrrii? Edw. and Haime, Brit. Foss. Corals, pt. ii.
joe WINS), jolls SS, see 4b,

I refer a dendroid species from Crickley to this species with great
hesitation. Only one fragment has been examined, and it is so
very crystalline that no internal examination can be made.

The columella appears to be rudimentary or wanting. The con-
fluent septo-costal rays are arranged transversely with the axis of
the branches, and the calices have a much clearer definition than
those of most of the species of Thamnastrea.

THAMNASTRHA FROMENTELI, 0.s.

Corallum thin and expanded. Above, somewhat convex with
irregular prominences; below, concave. There is no epitheca. The
calicular surface has one central large calice, surrounded by many
small ones scattered irregularly about. They are small, superficial,
and indistinct, and a very few septa enter into their composition.
There is no columella. The septo-costal rays are very thin and
flexuous. They have a very distinctly radiate arrangement, and are
traceable from the large central calice outwards to the margin of
the corallum. The synapticulee are abundant, thicker than the septa
from which they spring, cuneiform, and their points meet in the
interseptal loculi.

Diameter of the corallum 33 inches; height of the corallum in
the centre # inch.

The large central calice and the slight development of the sur-
rounding small ones, with the radiate disposition of the very thin
septo-costal rays, will at once distinguish this species.

One specimen only has been examined by me. It was obtained at
Crickley, but its position in the section was not ascertained.

T. M. Hali—On the Rocks of N. Devon. 305

DimorpHAsTR#A DuBIA, E. de From., Introd. 4 Etude des Polyp.
Fos. p. 224 (1858—1861).

Several examples of a Coral have been obtained directly from the
Coral-bed of Crickley which appear to answer to the description of
the D. dubia of M. de Fromentel, which is recorded by him as occur-
ring in the Coralline Oolite of Nathein, in Wurtemburg. They all
differ from that species, however, and indeed from the genus Dimor-
phastreea, in having a well-developed epitheca. In well-preserved
specimens the calices are placed in the bottom of circular grooves,
surrounding the central, or parent calice. These grooves have some-
thing the appearance of the calicular furrows in Latimeandra, but in .
much worn or polished specimens the calices are seen to be at equal
distances from each other, and in circles. In no example is there
any trace of columella. The large central calice, and the regular
disposition of the smaller ones around it, will identify the species
with the above genus; though the calicular furrows might at first
sight lead to the supposition that it is referable to some species of
the genus Oroseris.

The foregoing species, with the exception of Montlivaltia lens,
occur, there is no doubt, in what Dr. Wright designates the Lower
Coral Reef of the Gloucestershire Hills; for although some of them
were not taken directly from the reef, but were found weathered out
on the slope below, the nature of the still partially investing matrix
points out pretty clearly the source from which they were derived.

The occurrence of Montlivaltia lens in the Cephalopoda-bed, at
Crickley and near Chipping Campden, and associated at the latter
place with two other species of Corals, is interesting as showing an
approach to those conditions of oceanic life which became shortly
afterwards so highly favourable to the growth of Coralline existence.

A peculiarity observable in many of the Crickley Corals is their
thin and expanded form. This is more especially the case with
Isastreea expansa, Clausastrea consobrina, Thamnastrea Mettensis and
Th. Fromenteli. In some others this peculiarity, though less dis-
-tinctly marked, is not wholly absent. Thamnastrea Defranciana,
Th. Terquemt, and Dimorphasirea dubia, while characterized by a
somewhat turbinate form, are nevertheless often so much depressed
as to become almost discoid, with a somewhat foliaceous margin.

JV.—Tue tate Proressor Puiiiires on toe Norta Devon Rocks;
witH AN InrTropuctory NorsE
By Townsuenp M. Hatt, F.G.S.
sae Meeting of the British Association at Plymouth has not
unnaturally been the means of directing attention to some of
the most complex points of Devonshire geology, and of reviving the
discussion as to the age and position of the Devonian series in
North and South Devon. Mr. Jukes, it will be remembered, died
in 1869. Had he lived longer, his energy of purpose would
doubtless have led him to carry on the work he had begun, until
he could either prove the correctness of his views, or satisfy himself
that the generally accepted classification was, after all, the right one.
DECADE II.—VOL, Y.—NO. VII. 20

306 T. M. Hali—On the Rocks of N. Devon.

The followers of Jukes seem to confine themselves to those portions
only of the district which he had more specially studied—North
Somerset, Lynton and Pickwell Down; searching in almost hopeless
despair amongst the lower rocks, instead of beginning at the other
end of the scale, with the Millstone-grit, and tracing the beds
downwards. As a result, the fossiliferous beds of the Upper
Devonian have been almost entirely neglected, and their relation to
the Carboniferous slates passed over.

Possibly the real question at issue may not be settled in a satis-
factory manner until we get a new Ordnance Survey, with a six-
inch map on which to lay down our observations ; but in the mean
time I would submit that there was one geologist whose opinions
on the subject, had they been made equally public, would have been

received with all the respect due to his great local knowledge, and

his well-known caution in drawing inferences from facts. The
author of the “Palzozoic Fossils of Cornwall, Devon and West
Somerset” can no more use his pen in defence of the Devonian
rocks; but as one of his former pupils at Oxford, I know well the
unfailing interest he retained in everything relating to Devonshire,
both before and after Mr. Jukes’s first paper was read to the Royal
Geological Society of Ireland, in May, 1865.

The last visit paid by Prof. Phillips to North Devon was in
August, 1869. At the close of the Exeter Meeting of the British
Association, an excursion was made by about 200 of the members to
Bideford and Westward Ho! and having been selected as the guide
for the occasion, I asked my old master some days previously if he
would add a few words to what I was about to say with reference to
the North Devon rocks. This, with his usual kindness, he agreed
to do; and the short address he then gave was, it is believed, the
only one in which he publicly stated his views on the controversy
which at that time had apparently been brought to a termination by
Mr. Etheridge’s exhaustive paper,’ and by the subsequent death of
Mr. Jukes. Now the question has been re-opened, it seems only
fair that the opinions of one who was in every way so well qualified
to form and express them should be put on record for future use in
a more permanent shape than that of a newspaper cutting.

AS regards the accuracy of the following reprint, I may say that
the proofs were corrected by Prof. Phillips; and on subsequently
receiving copies of the North Devon Journal in which it appeared,
he wrote to me from Oxford :—‘‘ The account is very accurate; and
I wonder how any stenographer could take down the evea mTepocvTa
from the perch of rocks. In two parts only is there anything which
has struck me as requiring amendment,—when Murchison and
Sedgwick are mentioned, they seem to oppose one another. Not so.
They should be quoted as opposing De la Beche’s classification, and
rightly so. Say ‘immediately his conclusion was disputed by,’ and
again a little earlier, for ‘terms then unknown,’ read ‘then not
unknown.’ ”?

1 Quart. Journ. Geol. Soc. vol. xxiii. p. 568.
2 These corrections are shown in italics.

The late Prof. Phillips’s Address at Westward Ho! 307

ADDRESS DELIVERED BY Prorsssor PHiniries at Westwarp Ho! Norra
Devon, Aucust 26, 1869.

Ladies and Gentlemen,— All that we now see in action—all the
force of the waters and all the effect of the wind—has been in opera-
tion through an immensity of time. At some time removed from the
present was formed the deposit which we have just been looking at.
At some earlier time than that the sea-coast underwent great changes
of level with reference to the water, and here you have one of the
most conspicuous examples of a raised beach, proving to you that at
the time when it was formed the action of the water was of the same
nature as now it is in the distribution of these large pebbles, that
these pebbles are of the same order, coming from the same quarter,
and finally ground down to masses of about the same magnitude.
You see, also, that the ancient deposit of the beach was of con-
siderable thickness, and over the pebbles other matters have increased
which deserve a careful scrutiny. At an earlier date than that this
country was raised out of the water under which it was formed.
All the features of North Devon and South Devon primarily depend
on the movements which have taken place from below, which have
uplifted ridges of mountains and formed in the alternating spaces
hollows. Then there has come over the surface the enormous action
of long time and atmospheric waste, and what we see at the present
moment in every hill and valley, every waterfall and every stone, is
not merely the great force of ancient nature which sketched out the
forms of continents and islands, but the subsequent action of ordinary
daily, hourly, atmospheric agencies upon the surface ; so that many
persons who have satisfied themselves of the importance of diluvial
agency in producing great changes on the surface of the earth are
very much in the habit of believing that there is no necessity for
supposing that anything else than rain and rivers is required to
produce all the main changes, all the principal features of our interior
geography. Now, if you keep in your minds the fundamental pro-
position that every one of these stratifications we see on the north
and on the south have been formed under the influence of the sea,
that these almost vertical rocks were at one time laid flat, that they
have laminations in which are shells of the period, and many marks
proving beyond a doubt the original nearly-horizontal deposition of
this strata, you will perceive that in order to have the first elemen-
tary notions of the relation of the different parts of the land one
to the other, we must study those monuments that are so clear (and
nowhere so clear as on this coast), of the fact of the immense
elevation of the ancient sea-beds in order to produce the main
_ features of our interior land.

Now, as you pass from this part to the northern coast there are
some undulations in the general course of the stratification, but in a
general manner they rise from the northward, and the lower strata
of North Devon are found on the northern shore. Afterwards as
you pass by the stratification of Bideford and that district in which
the Culm deposits occur (as referred to by Mr. Hall), as you go
southward the stratification undergoes many undulations, some parts

308 The late Prof. Phillips's Address at Westward Ho !

of the sea-bed having been raised and some parts having been
depressed, until you reach the granite of Dartmoor, where the
stratification turns up against the great mass of granite rock upon
which until recently opinion was not divided. It has always been
imagined to be a mass of rock fused by the hot interior of the globe,
pressed upwards with great energy, and throwing up its stratifi-
cation towards the north and the south. But all human opinions
change,—even the opinions of scientific men who are supposed to
have most prejudiced notions with reference to their theories. Now,
some scientific men believe that the granite is the product of water
and not of heat. I must tell you frankly that I do not believe them—
on the contrary, I think there is evidence—absolutely perfect evi-
dence—that the granitic rocks were produced at a very great depth
in the interior of the earth. No doubt water was present, but the
granite was never dissolved in masses by its action. They were
solidified in the presence of water, and they contain small quantities
of water in some of their crystals; a thing no more to be wondered
at than that there is air in the sea and water in every one of the
stones we see around us. Now, the stratification which rests on this
granite has been perfectly traced, and in all the districts of Devon
there is no more interesting study than this county to the northward.
And what is curious is the fact that the stratification is clear in its
continuity. In the Bideford strata you have the lower Coal deposits,
and at Barnstaple you arrive at the Carboniferous age: then you
have the Pilton strata, mentioned by Mr. Hall, until you come to the
strata of Lynton and the red rocks of the Foreland. The stratifi-
cation is in regular order,—on the whole running from north to
south, and the sequence of the different strata is well known, though
I trust it will be better known in a few years by the continued
labours of my friend Mr. Hall, to whom we are extremely obliged
for acting as our conductor on this occasion. He lives on the spot
which is so celebrated for its fossils—Pilton is his native home, and
I am sure that in future years we shall live to acknowledge his
efficient and painstaking researches. What are these strata which
have been pointed out to us? When Sir Henry De la Beche, in the
year 1836, published his book on “The Geology of Cornwall, Devon,
and West Somerset,’ he considered that at that time terms, which
were then [not] unknown, such as “the transition series of rocks”
and the ‘“ greywacke group,” could be applied to large portions of
this county of Devonshire; but when afterwards sections of the
district were obtained with the greatest accuracy, it was found that
he was apparently quite wrong in his interpretation of the whole of
the strata from Bideford, southward to Dartmoor, for he referred
these deposits to an age much older than the deposits on the
northern side, and they are now known to be much younger. You
may think this was a great fault, but in my opinion it was a small
one considering the wonderful accuracy of the greater part of his
work. It was in consequence of a discussion on his observations
that I first had an opportunity of making an acquaintance with
North Devon, for immediately there was a dispute between [/is

The late Prof. Phillips’s Address at Westward Ho! 309

conclusion was disputed by| Professor Sedgwick and Sir Roderick
Murchison, and there was a doubt on the subject, I received a com-
mission from the Government to investigate the matter, being
supposed to be an impartial kind of person who was not disposed
to accept any conclusion very hastily, whilst giving to every one
the right to form an independent judgment of his own. I was sent
for the purpose of expressing an opinion on the point, and in con-
sequence I published a book on the subject.

With reference to the country to the North, still the question
remains, ‘“‘ What are we to call it?” Many are disposed to say that
a greater portion of the stratification of North Devon might be
joined with those great series of rocks containing the anthracite, or
culm, in the neighbourhood of Bideford, and become a part of the
Carboniferous system. Others, on the contrary, think that some
portions, especially to the northward, ought to be joined to the
Silurian series. Now, I think that scientific men are often greatly
mistaken as to the features of particular tracts of country. You
know the general history of Belgium—how 1,800 years ago it was
peopled by tribes who settled on a soil foreign to themselves, and
they have held it as well as they could against the Germans (the
Silurians) on the one side, and the French (the Carboniferous series)
on the other. Well, at the time when France swallows up Belgium,
or when, more probably, France and Germany take a slice each,
then I hope (and not before) we shall have settled this question
about the stratification of North Devon. The two sections are very
powerful and rather aggressive kingdoms, and it is difficult to defend
the North Devon territory against the demands of the Carboniferous
strata above and the Silurian strata below. As I would never desert
a falling cause (if this be one), I still declare myself in favour of
the independence of North Devon, and assert that there are strata
which are neither Silurian nor Carboniferous—that of themselves
they are worthy of a separate study, deserving separate names—and
that their history is remarkably interesting, connected as it is with
some of the most important movements on the crust of the globe.
Those movements were subsequent to the date of the deposition of
these rocks. Since these rocks were deposited a large portion of
the features of South Wales has been produced, the channel between
South Wales and Devon has been formed, and there has also been
produced the hollow that exists on the southern side of North Devon,
and all the undulations in the interior of the country; all Dartmoor
and the Cornish rocks have been raised since the days when the
North Devon deposit was produced in the ancient sea. Gentlemen
of Devon, never give up the independence of your country, hold to
the North Devon series, and if it is the case, as Mr. Godwin-Austen
invites us to believe it is, that they do not belong to the Old Red
Sandstone series, do not let us conclude that because they do not
belong to that particular class, they are nothing at all. Let us keep
the North Devon series distinct, as a separate characteristic—it is a
most interesting study, and, what is best of all, it is as yet not com-
pletely explored. Let us encourage by every means in our power

310 J. Durhan—On a Kitchen Midden near Dundee.

local residents, who have the best means at their command of com-
pleting a history which so many have attempted to give. Let us
doubt anything except this, that the North Devon strata are worthy
of a separate study, a separate name, and a separate history.

V.—Discovery or AN Ancient “KircHen MippEN” neAr DUNDEE.
By Jamzs Duruam, F.G.S.

ECENT operations in connexion with the Dundee Harbour
works have been the means of opening up a very interesting
section of superficial deposits.

In order to fully understand the position of the section, it must
be remembered that on either side of the Firth of Tay, as well as round
most part of the Scotch coast, are a series of raised beaches or gravel
terraces succeeding each other at vertical intervals of from five to
ten feet. Up to a hundred or a hundred and fifty feet above the
sea-level they are well marked, and are readily observed by the most
inexperienced eye. Above this height the old sea-levels can be
traced by means of wave-worn cliffs; but owing to the influence of
denudation, the terraces are extremely difficult to distinguish, or are
altogether wanting. Among the lower terraces none are usually
more conspicuous than a beach about 25 or 380 feet above the
Ordnance Survey datum-line, but. at a point about a mile east of
Dundee, called the Stannergate, it is by no means so prominent as at
other parts of the estuary ; the denudation of the slope behind having
buried it to a considerable depth under a mass of unstratified earth |
and stones, so that, instead of the abrupt terrace, the Stannergate
braes slope gently to the top of the cliff at the sea-margin. It is
to the burying of that old beach that we are indebted for the preser-
vation of the interesting remains that have just been brought
to light.

A cutting in connexion with the works referred to has exposed a
section from the very top of these superficial deposits to a con-
siderable distance into the rock beneath. The section is approxi-
mately as follows :—

Earth containing Stone Coffins, Urn, ete. a. see 3 to 4 feet
LORIN, TANONSMDEENEO! crs ae a Wigs ei Scores
Shell=bed Caters aires metsmicaniiccne eteves walt le aaeshapeeage abies 25
Graveliot raisedibeach) eles: Ll a ee ee os 9
Rock

The discovery of the stone coffins created considerable interest
among local antiquaries, two of them being what are termed short
cists, in which the body was buried in a sitting position, with the
knees brought up to the chin, which is supposed to be a very early
manner of interment; while an urn or rude earthen vessel, which
was found in one of them, is said to be of a very ancient type; but
it is to the shell-bed that the chief interest attaches. Very soon after
its exposure it was observed that, not only were the shells all broken,
but that, while the greater part of them were that of the mussel, in
no case were the valves found in their natural position, and at the
same time a very large proportion of them were those of adult

Notices of Memoirs. 311

animals. This led to a closer examination of the bed, when it was
found that mixed with the shells was a large quantity of burned
wood, with bits of burned horn and bone, while many of the shells
themselves had evidently been subjected to a strong heat. These
facts left no doubt that the bed was in many respects similar to the
famous Danish “ Kjokken Méddings.” During the progress of the
engineering operations, which have completely removed the shells,
a tolerably careful search was made for other traces of humanity, and
no implements that could safely be accepted as such were discovered,
although some bits of broken bone, the tyne of a deer horn, and,
most important of all, part of a long bone of some animal un-
mistakably split artificially, probably either with the object of
extracting the marrow or of fashioning an implement, rewarded the
search.

As the “ Midden” thinned out in any direction it was found to be
interbedded with the gravel of the old beach, and in one part was
overlain by a stratum of sand and gravel of some thickness, in
which could be found traces of burned wood and shells similar to
those of the “ Midden” below, just as we would expect to find it if
the heap had been formed close to high-water mark where it could
be reached by the waves of an unusually high tide, which would
throw the gravel over the shells, and partly interstratify them.

These facts would seem to prove that not only was the shell
mound a haunt of early man before the ten or twelve feet of earth, etc.,
was laid down upon it, but that the rude people who found in the
shells of the sea-shore their most convenient food-supply, lived
when the 25-feet beach was at the sea-level, and consequently when
the geography of the country was different from what it is to-day.

I am obliged to Prof. H. Alleyne Nicholson for kindly identifying
some of the fragments of shells sent to him as being those of
Mytilus edulis, Purpura lapillus, Tellina balthica and Littorina
littorea, all recent species, and the bit of deer horn as being “almost
certainly ” one of the tynes of the antler of the red deer.

NOTICES OF MEMOIRS.

I.—M. Ts. Fucus on THe OrIGIn oF FALSE-BEDDING.

In the “ Report of the Imperial Geological Institute of Vienna,”
September 30, 1877, M. Th. Fucus points out that when by great
storms, or high tides forced up against the land by strong winds, the
sea is massed up along the coast (as it is sometimes to the height of
10, 20, and even 380 feet), the coarser detritus, as shingle, blocks, and
boulders, is suddenly swept down to a lower level, even over the
mud-zone, by the deep and strong counter-current of the displaced
water finding its level again; thus giving rise to false-bedding on a
large scale and apparent local unconformity.—T. R. J.

I].—East-Arrican AMMONITES.

(Report Imper. Geol. Instit. Vienna, Sept. 30, 1877.)
A series of Jurassic Ammonites from the East Coast of Africa, col-

312 Reviews—Greological Survey of India.

lected by Dr. Hildebrandt, offer a striking analogy to those from the
Acanthicus-zone of Hast-India, published by Dr. Waagen. Some
Planulati among them may possibly be identical with Ammonites
torquatus or Amm. bathyplocus.——Count Marscuauu.

IiI.—F. Karrer on Miocrnz ForaMrinirera IN THE PHILIPPINES.
(Imper. Geol. Instit. Vienna, Report, September 30, 1877.)

The fossil Foraminifera at Luzon, in the Philippines, are Nodosaria,
Cristellaria, Polymorphina, Globigerina, etc., characteristic of a
rather deep-sea deposit. The same forms having been found in the
Nicobar Islands, Java, Celebes, and Borneo, an extensive Miocene sea
may be supposed to have existed from the Nicobars to Luzon.—
Count MarscHatu.

IV.—Dr. O. Lenz—On West-Arrican Growoey.!
(Report Imper. Geol. Instit. Vienna, December 4, 1877.)

Some Organic Remains have been collected near Landana and
Caconge, 5° 15’ Lat. §., and 12° Long. E. Greenwich, on the West
Coast of Africa. The coast there consists of steep cliffs and rocks,
rising to a height of 50 feet. Inland is a series of hills, projecting
from the West-Africa chain, which ranges N.-S., and is composed of
gneiss, mica-schist, tale-schist, quartzites, etc. This is the “Sierra do
Cristal” or “Sierra complida” of the Portuguese. On the banks of
the Gaboon and Ogowe Rivers (from 1° Lat. N., to 1° Lat. 8.) this
promontory consists of horizontal calcareous sandstones with
Cretaceous fossils. Further South, it appears as a deep-brown,
friable, very fine-grained ferruginous, and non-calcareous oolite.
In it are Corals, with Zeda, Mactra, Tellina, Cardium, etc. Remains
of Fishes, very well preserved, have been found near Landana,
about 86 miles south of Point Padron. A large slab of grey, fine-
grained, somewhat argillaceous sandstone contains the vertebra and
skull, with teeth and branchial arches, of a large Fish, more or less
compressed. ‘Teeth, also, and dorsal spines of a Ray, a tooth of a
Crocodile, a coprolite, and a very large and probably Cretaceous
Nautilus, were collected in the same locality. The last-mentioned
fossil was full of a light-coloured limestone, crowded with small
Gasteropods and Bivalves. The cliffs, 20 feet high, along the
coast of Ambrisetta, east of the mouth of the Congo (or “ Living-
stone”) River, are composed of a light-grey limestone abounding
with shells of Ostrea.—Count MarscHat.u.

RAVI WwWS.-.

I.—Recorps oF THE GEOLOGICAL Survey or Inp1A, VoL. xi. Pr. 1.
1878.

HE “ Records” of this Survey enter upon their second decade

with a quarterly part of nearly three times the usual size; the

first for 1878, containing, besides the Annual Report of the Superin-

tendent, several important papers by the officers: ‘‘ Notes on the

Geology of the Upper Godaveri Basin” (Hughes); “Notes on the

1 See Grou. Mac. New Ser. Vol. IV. p. 27.

Reviews—Geological Survey of India. 313

Geology of Kashmir, Kishtawar and Pangi” (Lydekker), both
accompanied by coloured geological maps; “Notices of Siwalik
Mammals” (Lydekker); “The Paleontological Relations of the
Gondwana System, a reply to Dr. Feistmantel” (Blanford, W. T.) ;
“ Note on Punjab Erratics” (Wynne) ; and the usual lists of addi-
tions to the Library. .

In the Annual Report the Superintendent describes the nature of
the Survey operations, and the progress made since the last Report
was published, entering at some length into the subject of explora-
tions for coal, which seem to have had in general rather negative
results. The recent Survey of the Sind -Tertiary marine and fresh-
water rocks are fully noticed, and the suggestion made that the Sind
sections may furnish an important clue to the horizons of con-
temporaneous strata in the Tertiary region of the sub or outer
Himalayan belt, where it is admitted that the changes in the com-
position of the deposits, and the great disturbance which these have
undergone, present a constant obstacle to tracing contemporaneous
zones.

The latter part of the Report is occupied by a disclaimer, in
language sometimes strong, at others most liberal, of responsibility
for the views and opinions conveyed in the papers which it becomes
the duty of the Superintendent to edit in the Survey publications.

Mr. Hughes’s paper treats of a district chiefly occupied by the
Gondwana system, and prominently so by the interesting Kota-Maleri
sub-group with its interesting fossil fish Lepidotus, Dapedius, and
Ceratodus, and the reptiles Parasuchus and Hyperodapedon, together
with a considerable number of fossil plants. These Gondwana rocks
are underlain by the Vindhan and Metamorphic groups, all being
unconformably overspread by outliers of the bedded “ Deccan trap
group.”

Mr. Lydekker’s paper and map give us what is likely to develope
into a complete Geological Survey and description of the interest-
ing country and neighbourhood of Kashmir, a thing which has been
long desired. Mr. Lydekker’s map still shows blank spaces, but so
much ground has been covered that a fair estimate can be formed of
the chief geological formations to be found.

The oldest of these are gneiss rocks seen at Darcha, the Wardwan
valley and Zanskar range, and in the range of Dhaoladar. The age
of this gneiss is undetermined, and it is overlain by another gneiss
formation seen in Kulu, on the Pir Panjal range, and overlying the
former gneiss at Wardwan and Lanskar range.

Resting on this are the slates and limestones of Pangi and Lahul,
overlain by the Lower Pir Panjal slates, and the lower slates and
trappoid rocks of the Kashmir valley and its vicinity. Newer than
these are the trappoid rocks of the Wular lake neighbourhood, upon
which come the Upper Pir Panjal slates, shales and trappoid rocks ;
both groups being considered ‘of Upper Silurian age, while the
underlying slates and trappoid rocks mentioned above are classed as
Lower Silurian and Cambrian (?).

Above this slate and trappoid series is a mass of limestones,

314 Reviews—Geological Survey of India.

slates, and sandstones, varying so much in lateral development that
the author considers it may have had separated areas of accumula-
tion. It is the first rock group in the ascending series found to be
fossiliferous and belongs entirely to the Carboniferous formation. In
it are represented, the author thinks probable, not alone the Krol
and infra-Krol groups of the Simla area, but the Carboniferous
Kuling series of Dr. Stoliczka’s Himalayan sections to the east.

Overlying this great Carboniferous formation come limestones,
dolomites, sandstones, and slates, mostly developed in the higher
mountains towards the interior of the Himalaya, and which are of
Rheetic and Triassic age, representing, perhaps, the Lilang series of
Stoliczka.

In a former paper, by himself and Mr. Medlicott, to which the
author refers frequently, the relations between the Pir Panjaél and
other Kashmir rocks and those forming the Outer Himalayan Tertiary
belt, are shown, the disturbed state of the junction being as great as
is usual along the Tertiary belt. From this inwards the whole of
the great Pir Panjal range is described as being an inverted or over-
thrown anticlinal arch bearing from the Kashmir valley towards the
outer Himalayan border hills.

Within the valley itself the ‘“‘Karewah” superficial beds, which
are of great thickness, and which have usually been regarded as
lacustrine, are referred here to a late Tertiary period, apparently
upon the evidence of a constant dip as high as 20°, with which they
rest upon the inner flanks of the Pir Panjal range. The question
seems mainly to depend upon the point whether this angle of dip
has been produced by disturbances (forming perhaps part of the
- movements accompanying the production of the Himalayan chain),
in post-Tertiary times, or whether superficial beds can be deposited
from water at angles so high as 20°. Evidence from organic remains
is not adduced.

The trappoid rocks of this country have been thought by some
previous observers, notwithstanding their trappean and amygdaloidal
aspect, to be merely varieties of metamorphosed strata, and by others
to be veritable traps. The author, after numerous opportunities of
studying this question, favours the latter view, and regards some of
the denser kinds as genuine igneous rocks, an opinion borne out by
the microscopic examinations of Colonel McMahon. The whole of
these trap rocks are older than Carboniferous.

In the absence of paleontological testimony to produce from the
lower rocks of Kashmir, and until it is shown that they have been
traced into continuity with fossil-bearing beds in other parts of the
Himalayan exposures, even more caution might have been used in
applying the terms “Cambrian” and ‘ Silurian” to these ancient
slates, gneiss, etc.

One very interesting point is the discovery by Mr. Lydekker of
numerous rolled boulders of an unknown gneiss in the lower slates,
which rest conformably upon the gneiss of these mountains—a
fact indicating the previous existence of very ancient metamorphic
ranges, whence he thinks these blocks may very possibly have been

Reviews—Geological Survey of India. 315

transported by ice or rafted among the roots of trees. The break
which this would establish in the Himalayan series seems hitherto
to have escaped all observers—but the field is a wide one.

The next paper by the same author is entirely paleontological.
It records the most important and interesting additions to the
Siwalik mammalian fauna made by Mr. Theobald from the rocks of
the Rawul Pindi plateau during the preceding season as well as
some from Sind collected by Messrs. Blanford and Fedden. Correc-
tions of previous determinations are also given.

Among the genera noticed and described are, Macacus, Mastodon,
Stegodon, Dinotherium, Hyotherium, Anthracotherium, Rhagatherium,
Cheromeryxz, Merycopotamus —like animals, Sus, Camelopardalis,
Hydaspitherium, Rhinoceros, Listriodon, Hystrix, Rhizomys, Felis,
Hycena, Mellivora, Meles (?), Amphicyon, Hycenarctos, and an alleged
Cetacean earbone considered by Professor Flower to belong to the
Ungulata.

One of the most important contributions to the number is Mr. W.
T. Blanford’s paper on the paleontological relations of the Gond-
wana system, a reply to Dr. Feistmantel’s many recent papers on
the same subject. Mr. Blanford is, on the whole, courteous, if severe,
and has taken much pains to examine critically the arguments of his
colleague, who is charged with making an undue use of the principle
of selection in regard to his comparisons between the Indian Gond-
wana and European Mesozoic flora; indeed, it is stated that he
employs no evidence among the mass available except that which
tells in favour of his own view.

Mr. Blanford disclaims the intention to set himself up as a palzo-
botanist, still he has sought and found evidence to form an easily
appreciable list of plants from the European Bunter, the Indian
Damuda (Lower Gondwana), and the Newcastle beds of Australia,
in parallel columns, which points to a very different result from that
arrived at by Dr. Feistmantel as to the Mesozoic age of this part of
the Gondwana formation.

The paper is a long one, and requires to be read to grasp its
importance. The conclusions arrived at by the author, shortly
stated, are—Ist, that the evidence adduced by Dr. Feistmantel as to
the Umia beds of Kach (with Trigonia Smeii, and T. ventricosa, etc.)
not being Upper Jurassic is insufficient and incorrect; 2nd, that the
proof for the Rajmahal group being Lias is also insufficient; 3rd,
that the Panchet group and the Keuper have not been sufficiently
shown of the same age or related by homotaxis; 4th, that the
evidence on which the Mangli beds are classed as Rhetic and newer
than the Panchets is based upon various mistakes and omissions ;
dth, that if the affinities of the plant-fossils with those in Huropean
rocks were alone regarded, the whole Gondwana system above the
Karharbari group would be probably classed as of an age from
Middle Jurassic to Rhetic, and the Lower Gondwéna Damuda flora
as newer than the Upper Gondwana Rajmahal, both Rajmahal and
Panchet beds being, according to Dr. Feistmantel, most closely
affined by homotaxis to the Rhztic minor European formation,

316 Reviews—Conversations with Little Geologists.

though between these two Indian groups there is the greatest
stratigraphical and paleontological break in the whole Gondwana
system; 6th, that no evidence of value has been produced for the
classification of the Damuda series as Lower Triassic (Bunter), the
Damuda flora having far less in common with the Bunter or any
Triassic European flora than it has with the Upper Coal-measures
of Newcastle, etc., New South Wales [presumably Carboniferous] ;
Tth, that Dr. Feistmantel’s classification of the Australian plant-
bearing beds on the authority of Mr. Clarke differs materially from
all the data published by Mr. Clarke himself, etc.; 8th, that the
Karharbari beds must be separated from the Damudas and classed
with the Talchirs ; 9th, that it is unwise to come to any positive
conclusion as to the Carboniferous or Triassic age of the Damuda
and Karharbari beds; 10th, that the Upper Gondwanas may be
equivalent to the European Jurassic series approximately, and the
Lower Gondwanas to Triasso-Permian, also approximately, but close
definition of minor horizons in the Gondwana system is premature ;
11th, and finally, that an attempt to define geological horizons in
countries remote from Europe by fossil plants alone, can only lead
to error: that Dr. Feistmantel’s attempt to make the Indian groups
suit the European sequence is a failure, and the constant assertion
that particular groups belong to distinct Huropean subdivisions is
misleading and unscientific.

Mr. Wynne’s note consists only of a few lines to set himself right
in consequence of an attributed ambiguity in his previous use of the
word ‘‘erratic,” in its oldest sense, for wandering fragments, the
sense in which he employed it.

II.—Conversations with Lirriy Groxtocists on THE Six Days oF
Creation. By J. W. Grovur,C.E. (With a Geological Chart.)
HE Preface shows this to be one of the many works which have

owed their publication to the well-meant but injudicious inter-
position of “friends of the author.” The writer acknowledges his
obligations to “Hugh Miller, Dr. Buckland, and McCausland,” as
well as “those standard authorities Lyell, Murchison, Figuier (!),
and Dr. Lindley.” On p. 1, however, in answer to a question,

“Did Moses, who wrote the Book of Genesis, understand Geology ?”

the author remarks, “Not as we do; he wrote as he was inspired

or taught by God Himself,” and adds, ‘I want to show you how
wonderfully the formation of the earth confirms the first chapter in
the Bible.”

Mr. Grover follows Hugh Miller and some other geologists of a
former generation, in considering the six days of Genesis to mean
six long periods of time, and one of the peculiarities of the
author is the rigidity with which he settles the duration of these
periods. The first day includes the Cambrian, the second the
Silurian periods, while the third comprises the Devonian and Car-
boniferous. The Permian and Triassic rocks were the work of the
fourth day, and the Lias, Oolite, and Chalk of the fifth. The sixth
day includes the Tertiary strata, up to the ‘‘Diluvium.” Nothing

Reviews—Postlethwaite’s Mining in the Lake District. 317

is said of Laurentian or Lewisian rocks; their place, however, would
evidently be with the productions of the first day. The Diluvium
is described as “a deposit supposed to have been caused by an
immense wave or deluge which passed over Europe and other parts
of the world, especially Asia.”” Some more precise information
as to the whereabouts of this unique formation seems desirable.

On page 8 the author appears as an extreme evolutionist. He is
asked, “So God began by making the smallest and most imperfect
creatures?” He replies, “ Yes. ... His great laws continue the
same now, nothing great is done at once, but by slow degrees ; all
discoveries and inventions begin by imperfect forms in the first
instance, and they grow and improve from year to year till at
length they attain their full development.’’ This comparison of the
operations of the Deity with those of men gifted with mechanical
ingenuity scarcely seems well chosen, though the author is doubt-
‘less to be acquitted of anything like intentional profanity. On
page 9, however, Evolutionists get but scanty justice. Some of
them, according to Mr. Grover, find that there is a relationship
between frogs and men, “inasmuch as the frog is the only animal
which has a calf to its leg.” No clue is given to the authorship of
this remarkable view, and we are afraid that Mr. Grover has been
caught by the “chaff” of some jocular Naturalist.

Many serious blunders occur, both from want of more accurate
knowledge of common facts, and also as misprints. On page 13 we
read, “Foraminifera, which is a mass of very feebly animated matter ;
seen through a microscope it resembles the roe of a fish.” And again,
on page 5, “It is the unclouded sunbeam which strengthens the
fibres of the plant, and forms the hard woody substance in trees.”
The remark about Foraminifera is certainly calculated to puzzle the
childish understanding, while the passage about wood and sunbeams
is likely to lead to the error of supposing them simply different forms
of the same substance. This can hardly have been Mr. Grover’s
intention. The identification (p. 1) of the distinguished theologian
known as St. Augustine with the Augustine who, two centuries
later, converted the King of Kent, is objectionable in the interests of
accuracy, though not of geology. Certainly the crudity in conception
and looseness in execution of this work must ever prevent it, in its
present form, from filling the place designed for it by its author, in
spite of his remarkable ingenuity and good intentions.

Well said the Duke of Argyll, in reference to popular works on
Geology, that none but our most able writers should venture to
undertake them; and forasmuch as they were designed for the
instruction of those but little informed upon the subject, they should
above all things be accurate. A Venele

T]]J.—Mines anp Minine in toe Laxe District. By Jonny Postiz-
THWAITE. (Leeds, 1877.)

ESWICK, situated in the midst of some of the wildest and most

picturesque scenery of the Lake District, is not less remark-

able for the natural beauty of its surroundings than for its indigenous

318 Reviews—Postlethwaite’s Mining in the Lake District.

sources of mineral wealth, the knowledge of which is of great antiquity,
some of the mines having been worked by the Romans during their
occupation of this country, and probably by the Britons before them.

Both the physical features and the mineral contents of the rocks
are due to the geological character of the district, which consists
chiefly of the Skiddaw slates, with the associated granite and meta-
morphic schists, and the overlying green slates and porphyries
(Borrowdale series). These rocks, elevated, indurated, contorted and
faulted, have subsequently and for long ages been weathered and
disintegrated by various meteoric agencies acting on the hard and
soft strata,—thus producing the present irregular outline of cliff,
ravine and valley, due primarily and partly to a former glacial
period which has left its traces in the scored rocks, rounded hum-
mocks, and thick accumulations of moraine materials in the present
valleys, and which, as well as the other geological features, have
been so ably described by Mr. C. Ward in his memoir lately pub-
lished and noticed (Gon. Mac. 1877, p. 280).

On the other hand, the mineral veins and lodes are the result of
those mysterious processes, deeply seated perhaps, by which the con-
taining fissures became filled with various kinds of metallic matter,
with which the Lake District abounds, for no less than 86 species of
minerals have been noticed, of which 46 are metallic, and 40 non-
metallic; some of them being most rare and beautiful forms. The
principal mines from which these minerals have been obtained are
arranged by the author in the order of the strata in which they
occur, commencing with those in the Skiddaw slates, which are
numerous and extensive, the veins being generally large and well
mineralized, but sometimes irregular in the deposits of ore.

The mines in the green slates and porphyries are not so numerous
as those in the Skiddaw slates, but some of them are much more
productive. ‘The most remarkable of these mines is the plumbago
mine, which is well known to be unequalled for the purity of the
graphite obtained from it; the containing vein or dyke is a species
of hard trappean or diabasic rock of a peculiar nature, the deposits
of plumbago occur in sops or pipes of various sizes, and not in veins.
The Coniston copper mine and the Greenside lead mine are in the
same formation, the latter being one of the most valuable mines in
the North of England.

The mining field of Caldbeck Fells is in the porphyritic syenite,
in which seven distinct mines have been opened. Of these the most
important and productive is the Roughtengill, both as regards the
quantity and variety of its ores and minerals. Besides the metallic
mines, the Caldbeck district includes the north-western portion of
the West Cumberland coal-field, in which a small seam of coal was
wrought as early as 1790.

The work is illustrated by a map of the mining field of the Lake
District, with section and plans of the principal mines, together with
a synopsis of the State papers relating to the mines and smelting
works near Keswick. The author, practically acquainted with the
mining district, and evidently interested in the mineral development

Reviews—Illustrations of Fossil Plants. 319

of his country, has produced this concise and useful account of the
past and present mining industries around Keswick, their failures and
successes, and their present abeyance, in order to perform a patriotic
duty, by correcting a very prevalent, but erroneous, notion respect-
ing the mineral deposits of the Lake District, with the hope of
directing more attention to the subject, so that it may at some future
time become as famous for its mineral productions as it is now for
its beautiful scenery. J. M.

TV.—In.usrrations oF Fosstz Prants; being an Autotype Repro-
duction of Selected Drawings, prepared under the supervision
of the late Dr. Linputey and Mr. W. Hurron, between the
years 1835 and 1840, and now for the first time published by
the North of England Institute of Mining and Mechanical
Engineers. Edited by G. A. Lesour, F.G.S., Newcastle-on-
Tyne. Royal 8vo., containing 64 Illustrations in Autotype,
with Portrait of W. Hutton. (1877: Published for the
Institute by Andrew Reid, Printing Court Buildings. London :
Longmans & Co.)

HE “ Fossil Flora” of Lindley and Hutton has been for more

than forty years a standard work on British fossil plants, and it
is hoped that it may be still further supplemented by the publication
of the promised fourth volume under the able superintendence of Mr.

W. Carruthers, F.R.S., containing not only corrections of former

descriptions, the result of new observations, but the addition of

many new and interesting forms which have appeared in | this

Magazine, and other Geological Journals, besides the special

memoirs by Mr. Binney in the Paleontographical Society and

Prof. Williamson in the Transactions of the Royal Society since

the publication of the original work.

The study of fossil botany has been much advanced during late
years, by the issue of numerous and important memoirs on fossil
plants both in Europe and America, so that ample means exist for
the further comparison of the British forms with those of other
continental areas. Among the more general works of interest are
Dr. Dawson’s Acadia, Rogers’s Pennsylvania, Prof. L. Lesquereux
on the Cretaceous and Tertiary floras of America; those by Geinitz,
Mougeot, Ettingshausen, Saporta, and Géppert, the botanical parts
of the Paleontographica, and of the Paléontologie Francaise,
Schimper’s Paléontologie Végétale, M. Grand Eury’s ‘Carboniferous
Flora of Central France,” and other papers in the Spanish, Italian,
and Russian journals.

The present volume may be considered as an addenda to the
“Fossil Flora,” as it consists of a series of sixty-four plates, repro-
duced by the autotype process, of a selected number of original
drawings, which had evidently been prepared for a continuation of
that work.

These drawings formed part of a large collection belonging to the
late Mr. W. Hutton, and were presented to the North of England
Mining Institute by Mr. Hubert Laws. Having been prepared

320 Reviews—Devonico- Carboniferus.

under the supervision of the late Dr. Lindley and Mr. W. Hutton
between the years 1835 and 1840, but not published, the Council
of the Institute resolved to publish the more important figures, of
undescribed, rare, or beautiful specimens, most likely to prove of
value to the student of fossil botany, and hence the origin of the
above work, the editing of which was entrusted to Mr. G. A.
Lebour, who has appended to each plate a few brief remarks as to
the general character of the specimen figured, without a distinct
diagnosis, but with slight references to allied forms, and the localities
from whence they were obtained. The editor has, however, made
use of the notes referring to the plates left by the authors of the
“Fossil Flora,” or their correspondents. The specimens figured
were mostly obtained from the Coal-measures of the North of
England, and consist chiefly of species of Newropteris, Pecopteris,
Sphenopteris, with forms of Sigillaria, Lepidodendron, Calamites
and their foliage, and also some excellent examples of those am-
biguous remains of plants referred to roots and rootlets. It may be
useful for those who may hereafter wish to compare the specimens
referred to in this work, to know that the original carefully executed
drawings are in the Library of the Institute, while the fossils
themselves have been deposited by the Council in the Museum of
the Natural History Society of Newcastle. J. M.

V.—Tuesaurus Devontco-Carponirerus : Toe Frora anp Fauna
OF THE DEVONIAN AND CARBONIFEROUS PrERIops. THE GENERA
anp Sprcies ARRANGED IN TABULAR FoRM, SHOWING THEIR
Horizons, RecurRENcES, Locaities, AND oTHER Facts. By
J. J. Biassy, M.D., F.R.S., F.G.S., ete.

NOTHER work has appeared from the pen of one of the oldest
and perhaps one of the most painstaking and laborious of living
geologists. In 1868 Dr. Bigsby published his Thesaurus Siluricus,
and he now issues his new volume of the ‘Thesaurus Devonico-

Carboniferus,” consisting of 450 pages of closely-printed matter,

arranged in tabular form, the result of eight years’ continuous and

almost uninterrupted labour. To attempt to estimate by the size of
the volume the work accomplished by the author, large as it is, is
totally to under-estimate the immense labour bestowed and the
minute and careful research required to produce so great a com-
pendium of palaontological facts as that attempted and so success-
fully carried out by Dr. Bigsby. Such works are “lasting monu-
ments of the learning, labour, zeal, and research” of their authors.
The author of the Thesaurus has chronicled with faithfulness the
paleontological results of all that has been done in Devonian and
Carboniferous geology in Europe, Asia, and America, tabulating under
their respective families every known genus and species, with their
chief localities, and one, and sometimes two, references, commencing
with the Plante in each of the two geological periods, and then
ascending through the whole Zoological series, from the Protozoa to
the Pisces and Amphibia. The great value of this Thesaurus to the
student consists in the (almost in every instance) correct reference

Reviews—Devonico- Carboniferus. 321

given to the species under their respective genera, thus furnishing
us with a census of the Fauna and Flora of the Devonian and
Carboniferous rocks of the world. Those who know the detailed
labour, time, and anxiety involved in making 80,000 to 100,0U00
references will best appreciate the service rendered by Dr. Bigsby
to Paleontological science. The contributions of every author are made
manifest, but so voluminous and complicated are works of reference
now, that it is not easy, nay, at times it is next to impossible
(except in public libraries), to obtain complete evidence of the
labours of foreign geologists, so as to arrive at facts and reliable
data as to the history and distribution of life through time and space.
Such, however, is the painstaking and laborious nature of the task
requisite in order to collect and verify every species in the Thesaurus
just issued by Dr. Bigsby.

The plan is comprehensive and clear, showing at once the distri-
bution of every species known to have existed, and which now
constitutes the Devonian and Carboniferous Fossil Fauna and Flora.
The results of appearance and distribution, etc., are given in separate
tables at the end of each sub-kingdom or class. This résumé em-
bodies both the geographical or distribution in space, as well as the
geological and stratigraphical, or distribution in time.

It is the tabulation of such results that leads to clear generaliza-
tions, and, as in the present case, affording a knowledge of the dis-
tribution of Devonian and Carboniferous life over the globe, and this
is the aim and end of Dr. Bigsby’s work. No library of reference,
public or private, should be without such works. Certainly no
geological library can be said to be complete that does not contain
upon its shelves such works of reference as will enable the student
in natural science to obtain correct and ample data both certainly
and readily.

Dr. Bigsby has greatly aided paleozoic paleontologists by the
compilation both of his Thesaurus Siluricus, in 1868, and the present
contribution on the Devonian and Carboniferous groups, no genus or
species seem to have been omitted or overlooked. Fourteen countries
or areas in Hurope, and fifteen in America, have been selected as
geographical localities for the distribution of the Carboniferous
species. ‘The Huropean are Ireland, Scotland, England, Belgium,
France, Rhenish Prussia, Westphalia, Silesia, Hartz, Moravia,
Bohemia, Saxony, Russia in Europe, and the Altai. In America.
Arkansas, Kansas, Nebraska, Missouri, Jowa, Michigan, Illinois,
Indiana, Ohio, Kentucky, Tennessee, Pennsylvania, Nova Scotia, Cape
Breton, New Brunswick. The labours of the numerous American
and European Palzontologists who have enriched the literature of
their respective countries are faithfully chronicled, and the horizons
and localities of their fossils given.

In the Silurian Thesaurus of 1868, Dr. Bigsby discussed with
great ability, under his “facts and observations,” seven questions or
subjects of high importance to a right understanding of the distri-
bution, and laws of life through all time. These may well be con-
sulted with reference to the present volume, bearing as they equally

DECADE II.—VOL. V.—NO. VII. i 21

322 Reviews—Stanford’s Geological Map of London.

do upon its whole contents. Those chapters on locality, first
appearance, extinction of species, migration, and recurrence, in the
Silurian Thesaurus, although not given in the Devonian and Car-
boniferous volume under notice, should be referred to as master-
pieces of logical deduction. Continental and American geologists
and authors will gladly hail the work before us, and wish that
length of life could be spared to its author to complete in the
same manner the Secondary formations of the world. The geologist
deals with time, and time has dealt kindly with the author of the
Catalogue of the Flora and Fauna of the Devonian and Carboniferous
periods. Great is the muster-roll of past life that he has chronicled
through time in this volume, nor will the chronicler of the future
fail to inscribe among the names of the great and good in geological
science, who have by their patient labours contributed to the store
of our common knowledge, the honoured name of Joun J. Brassy.

VI.—Sranrorp’s GxrotocicaL Mar or Lonpon anp 1Ts SUBURBS.
Scale 6 inches to a mile. The Geology compiled from the Maps,
etc., of the Geological Survey by J. B. Jonpan. 24 Sheets in
Portfolio, with Index. (1878.)

HE Geological Survey, having published no other map than the
ordinary one, on the scale of an inch to the mile, Mr. Stanford
has boldly come forward to supply the want of a larger one, using
for the purpose his well-known “Library Map of London.” 'The
work is substantially the same as that which forms the surface of
the large model of London in the Museum of Practical Geology,
and as Mr. J. B. Jordan was employed in the colouring, ete., of that
model, our enterprising publisher has done well in securing his
services in the compilation of the geological information.

The area of the district represented may be judged from the
places shown near its corners, which are as follows :—Wimbledon
on the 8.W., beyond Hampstead on the N.W., Leyton on the N.E.,
and Beckenham on the §8.E. The formations shown by distinctive
colours are Alluvium, Brickearth, Gravel and Sand, Lower Bagshot
Sand, London Clay, Oldhaven Beds, Woolwich and Reading Beds,
Thanet Sand, and Chalk. It will be seen, therefore, that those
surface-deposits of gravels, brickearth, etc., which have so much
effect on the character of the ground, although of small thickness,
are not neglected, but are shown equally with the thicker formations
(London Clay, Chalk, etc.). It has not been thought advisable, how-
ever, to distinguish the gravels of different ages (though this is done
on the above-mentioned London Model), those of older date occurring
in such very small areas as to make the expense of employing two
additional colours not worth incurring.

Of course this map does not pretend to compare for accuracy
with the “Six-inch” Maps of various northern parts issued by the
Geological Survey, the geology on which has been actually surveyed
on that scale; it is of necessity, to a great extent, an enlargement of
the “ One-inch” Map, as far as the geology is concerned; though

Reports and Proceedings— Geol, Soc. London. 020

not altogether, as may be seen from the description of the London
Model in the little «‘Guide to the Geology of London,” published
by the Geological Survey.

Each of the 24 sheets can be had separately, or the whole
mounted together on a roller, so that the map can be made available
for the pocket, the book-case, or the lecture-room.

So far as we know there is no other case, but that of the late
Mr, Sanders’ large map of Bristol, of the publication of a geological
map on so large a scale, as a private enterprise—such things are left
to Government Surveys—and therefore we trust that in the present
instance both publisher and compiler may be well rewarded. W.

REPORTS AND PROCHHDINGS.
SitsNce

GeronoercaL Socrety or Lonpon.—I.— May 8, 1878. — Henry
Clifton Sorby, Esq., F.R.S., President, in the Chair.—The following
communications were read :—

1. “On the Glacial Phenomena of the Long Island, or Outer
Hebrides.” 2nd paper. By James Geikie, Esq., LL.D., F.R.S., F.G.S.

In this paper the author gave some additional notes on the
glaciation of Lewis, and a detailed account of the glacial phe-
nomena of Harris and the other islands that form the southern
portion of the Outer Hebrides. Additional evidence was adduced to
show that Lewis had been glaciated from 8.E., to N.W., and the
shelly boulder-clays and interglacial shell-beds of that part of the
Long Island were described in detail. Harris, North Uist, Benbecula,
South Uist, Barra, and the other islands that go to form the chain of
the “ Long Island,” were successively described under the headings
of Physical features, Geological structure, Glaciation, Till or Boulder-
clay, Erratics and perched blocks, Morainic débris and Moraines,
Freshwater lakes and Sea-lochs. Numerous bearings of strize, which
abound, were given, and these were held to prove that the whole
Outer Hebrides have been glaciated by ice that flowed outwards
from the mainland of Scotland. The position of abundant roches
moutonnées points to the same conclusion, and this is still further
supported by the ‘“‘travel” of the Till. That deposit is generally
absent or very sparingly present on the rock-faces that look towards
the mainland, but it is heaped up in their rear, and spreads over the
lower tracts that slope gently towards the Atlantic. On the west
side of the islands not a few boulders occur in the Till which have
been derived from the east; and the same is true of certain erratics
lying loose at the surface of the ground. ‘The islands are well
glaciated up to a height of 1600 feet above the sea; and the line of
demarcation between the glaciated and non-glaciated areas is
extremely pronounced. Above 1600 feet the hills show rugged,
splintered, jagged, and sometimes serrated tops. The author re-
garded the Till or boulder-clay as the morainic material that gathered
underneath the ice, and proof of this is given. Hrratics and perched
blocks are very numerous, and most of these, as well as much of the
morainic debris, are believed to have been dropped where we now

324 Reports and Proceedings—

find them during the final melting of the ice-sheet. It was shown,
however, that certain erratics and perched blocks and some well-
marked moraines are due to local glaciers, as are also some of the
striations in a few of the mountain-valleys. The origin of the rock-
basins, which are now lakes, was discussed, and attributed to the
erosive action of ice. To the same cause were assigned the rock-
basins which occur in certain of the sea-lochs.

In concluding, the author pointed out that we may now arrive at
a true estimate of the thickness attained by the ice-sheet in the
north-west of Scotland. If a line be drawn from the upper limits of
the glaciations in Ross-shire (3000 feet) to a height of 1600 feet in
the Long Island, we have an incline of only 1 in 210 for the upper
surface of the ice-sheet; and of course we are able to say what
thickness the ice reached in the Minch. Between the mainland and
the Outer Hebrides it was as much as 3800 feet. No boulders
derived from Skye or the mainland occur in the Till of the Outer
Hebrides, and this was explained by the deflection of the lower
portion of the ice-sheet against the steep wall of rock that faces the
Minch. The underpart of the ice that flowed across the Minch
would be deflected to right and left against the inner margin of the
Long Island; and the deep rock-basins that exist all along that
margin are believed to have been scooped out by the grinding ‘action
of the deflected ice. Towards the north of Lewis, where the land
shelves off gently into the sea, the under strata of the ice-sheet
were able to creep up and over the district of Ness, and thus gave
rise to the lower shelly boulder-clay of that neighbourhood, which
contains boulders derived from the mainland. The presence of
the overlying interglacial shell-beds proves a subsequent melting
of the ice-sheet, and a depression of the land for at least 200
feet. The overlying shelly boulder-clay shows that the ice-sheet
returned and overflowed Lewis, scooping out the older drift-
beds and commingling them with its bottom moraine. The
absence of kames was commented upon, and shown to be inex-
plicable on the assumption that such deposits are of marine origin ;
whilst if they be of torrential origin their absence is only what
might be expected from the physical features of the islands. The
only traces of post-Glacial submergence are met with at merely a
few feet above present high-water mark.

2. “Cataclysmic Theories of Geological Climate.” By James
Croll, Esq., LL.D., F.R.S. Communicated by Prof. Ramsay, LL.D.,
F.R.S., F.G.S.

The author commenced by calling attention to the great diversity
of the hypotheses which have been brought forward for the explana-
tion of those changes in the climate of the same regions of the
earth’s surface which are revealed by geological investigations, such
as alterations of the relative distribution of sea and land, of the
ecliptic, and of the position of the earth’s axis of rotation, all of
which, he maintained, have proved insufficient or untenable. Sir
William Thomson has lately maintained that an increase in the
amount of heat conveyed by ocean-currents, combined with the effects

Geological Society of London. 325

of clouds, winds, and aqueous vapour, is sufficient to account for the
former prevalence of temperate climates in the Arctic regions, and
this view, the author stated, he had himself been contending for for
more than twelve years. He thinks, however, that alterations in the
excentricity of the earth’s orbit is the primary motive cause, whilst
Sir William Thomson believes this to be the submergence of circum-
polar lands, which, however, in Miocene times, appear to have been
more extensive than at present. He pointed out that a preponderance
of equatorial land, as assumed by Sir Charles Lyell to account for
the milder climate of Arctic regions in Miocene times, would rather
tend to loss of heat by rapid radiation into space, whilst water is re-
markably powerful as a transporter of heat, so that, in this case,
equatorial water rather than equatorial land is needed.

In speaking of the glacial climate, the author maintained that
local causes are insufficient to explain so extensive a phenomenon.
He indicated that we are only too prone to seek for great or cata-
clysmic causes, and although this tendency has disappeared from
many fields of geological research, this is not the case in all. His
explanation of the causes of a mild climate in high northern latitudes
is as follows :— Great excentricity of the earth’s orbit, winter in
perihelion, the blowing of the south-east trades across the equator
perhaps as far as the tropic of Cancer, and impulsion of all the
great equatorial currents into northern latitudes ; on the other hand,
when, with great excentricity, the winter is in aphelion, the whole
condition of things is reversed; the north-east trades blow over into
the southern hemisphere, carrying with them the great equatorial
currents, and glacial conditions prevail in the northern hemisphere.
Thus those warm and cold periods which have prevailed during
past geological ages are regarded by the author as great secular
summers and winters.

3. “On the Distribution of Ice during the Glacial Period.” By
T. F. Jamieson, Esq., F.G.S.

The author believes that a study of the distribution of ice during
the Glacial period proves that the greatest accumulations of snow
took place in precisely those districts which are now characterized
by a very heavy rainfall, and he pointed out how exactly this is in
accordance with the views of Prof. Tyndall as to the conditions most
favourable to the development of glaciers. In support of this con-
clusion he reviewed the phenomena presented by the most highly
glaciated districts of the British Islands, of Scandinavia, and HKurope
generally, and of Asia and North America, and contended that in
every case his opinion is borne out, the districts which are now re-
markable for an excessive rainfall having been formerly centres of
dispersion for great systems of glaciers. The notion of a polar ice-
cap he held to be opposed to many well-known facts; and he dis-
cussed the distribution of various forms of life during and since the
Glacial epoch, with the object of determining whether the drainage
of ice from the great polar basin was effected by means of the de-
pression of Davis’s Straits or of Behring’s Straits. The evidence
appeared to him to be in favour of the former channel.

326 Reports and Proceedings—

IIJ.—May 22, 1878.—Henry Clifton Sorby, Esq., F.R.S., President,
in the Chair. The following communications were read :—

1. “On the Serpentine and Associated Igneous Rocks of the
Aryshire Coast.” By Prof. T. G. Bonney, M.A., F.G.S., Professor
of Geology at University College, London, and Fellow of St. John’s
College, Cambridge.

In.a paper published in Q. J. G.S. xxii. p. 513, Mr. J. Geikie states
that the rocks of this district are of sedimentary origin, a felspar-
porphyry being the “maximum stage of metamorphosis exhibited by
the felspathic rocks,” and the diorite, hypersthenite, and serpentine
being all the result of metamorphism of bedded rocks. This view
is also asserted in the catalogue of the rocks collected by the Geolo-
gical Survey of Scotland. The author had seen specimens of rocks
from this district which so closely resembled some from the Lizard,
that he visited the Ayrshire coast in the summer of 1877. The con-
clusions formed in the field have since been tested by microscopic
examination. He finds that several, at least, of the group of
“ dioritic ” rocks are of igneous origin, and are dolerite and basalt,
since they contain augite, not hornblende. The serpentine is un-
doubtedly an intrusive rock, the evidence being abundant and re-
markably clear. One specimen can hardly be distinguished at sight
from the black serpentine of Cadwith (Lizard); the resemblance
also is most striking when the rock is examined chemically and
microscopically. Hxamination of different varieties shows the
serpentine to be, like that of Cornwall, an altered olivine-enstatite
rock. The rock called hypersthenite is also intrusive. The author
found no hypersthene. ‘There are two varieties—one a remarkable
rock, consisting mainly of large crystals of diallage, a gabbro ex-
tremely rich in this mineral and almost free from felspar; and a
gabbro of later date, much resembling the ordinary gabbro of the
Lizard, the felspar being converted into a kind of saussurite, and
some of the diallage into hornblende. The “ felspar-porphyries”’
appeared to the author in the field to present all the characters of
true igneous rock, to be associated with tuffs, and to be unconform-
able with the above-described group of rocks. Microscopic examina-
tion placed their igneous character beyond doubt. There are also
some basalt-dykes of later date than the above. The author is
accordingly of opinion that the principal conclusions of the paper
referred to above are not warranted by either stratigraphical or
lithological evidence. He considers it probable that the “ felspar-
porphyry,” like so much of that in Scotland, is of Old Red Sandstone
age, and that the serpentine is of later date, but Paleozoic.

2. “On the Metamorphic and Overlying Rocks in the Neighbour-
hood of Loch Maree, Ross-shire.” By Henry Hicks, M.D., F.G.S.

The rocks in the neighbourhood of Loch Maree have been de-
scribed by various authors, but chiefly and most recently in papers
communicated to the Geological Society by Prof. Nicol, of Aberdeen,
and by Sir R. Murchison and Prof. Geikie, of Edinburgh. The
views held by these authors in regard to the order of superposition of
the rocks are well known to be greatly at variance, not only as

Geological Society of London. 327

regards some of the minor subdivisions, but in relation to the actual
age of nearly the whole of the rocks to the east, or those forming
the Central Highlands. The older geologists and, more recently,
Prof. Nicol, hold the view that the Central Highlands consist almost
entirely of the old fundamental (pre-Cambrian) gneiss, or rocks of
that age; whilst others, represented by the late Sir R. Murchison
and by Prof. Geikie, say that the rocks forming the whole of the
Central Highlands are of much later date, and for the most part of
Silurian age. In the present communication the author endeavours
to show, from results obtained by him recently by a careful ex-
amination of a section extending from Loch Maree to Ben Fyn, near
Auchnasheen, that the interpretations previously given are in some
important points incorrect, and that this has been to a great extent
the cause of such very diverse opinions.

The section described by him runs for some miles along the north
shores of Loch Maree, is then continued in a §.H. direction along the
heights opposite Kilrochewe and across Glyn Laggan, and then in
an easterly direction through the heights on the north of Glyn
Docherty to Ben Fyn and the range of mountains to the north of
Auchnasheen.

On the western and for some distance along the north shores of
Loch Maree the Lewisian rocks (fundamental gneiss series) are seen
to consist chiefly of reddish or greyish gneiss and hornblende- and
mica-schists. The strike in these beds is more or less continuous
from N.W. to S.E., varying occasionally to N. and 8., and they dip
generally at a high angle and are much contorted. Resting uncon-
formably upon this gneiss series, and forming here the upper part of
the mountain Slioch (about 4000 feet high), are the Cambrian con-
glomerates and sandstones, made up chiefly of masses of the rocks
below cemented together by a comparatively unaltered matrix. In
this, however, he found masses of other rocks, very similar to those
found in the Cambrians of Wales, and which he thinks must have
come from beds of an intermediate age, like the Pebidian series in
Wales, and which have either been completely denuded off here, or
which must be present in some other area not far distant. These
beds are, for the most part, nearly horizontal; but on the east side
they dip slightly to the S.E., where they are succeeded unconform-
ably by the quartzites of Crag Roy (these quartz rocks are also
beautifully exhibited on Ben Hay, to the south of Loch Maree, and
resting unconformably on the Cambrian rocks of the magnificent
Torridon Mountains). Alternating with these rocks are some of the
so-called fucoidal bands, the beds all dipping with a considerable
inclination to the S.E. Upon the quartzites are seen the Limestone
bands, occupying chiefly the sloping ground on the west side of
Glyn Laggan. ‘These are penetrated by a great mass of granitic
rock, which produces here considerable contact-alteration, the lime-
stone, however, at some distance from the mass being in a compara-
tively unaltered state. In all sections across Glyn Laggan hitherto
described the mass of intrusive rock is made to penetrate along the
bedding, and is supposed to separate the Limestone entirely from

328 Reports and Proceedings—

the upper series of rocks, the so-called Upper Gneiss, etc. The
author, however, found another series of sandstones, calcareous
grits, and blue flags beyond the main intrusive mass, and occupying
a considerable portion of the gradually descending ground between
the river and the heights on each side. These were also penetrated
by another arm of the granite, but, as in the case of the limestone,
with the sole result of altering them near the junction. Prof. Nicol
places a fault at this point, and says that the fundamental gneiss is
here brought up to give an appearance of overlying conformably the
unaltered series. The author, however, holds, with Sir R. Murchison
and Mr. Geikie, that the next is a younger series, and that it truly
overlies the unaltered beds; but he entirely demurs to the view held
by them that these should in any way be called gneiss rocks, or
associated in any way with beds which have undergone the meta-
morphic change so characteristic of the pre-Cambrian rocks as known
in this country, and which could only be induced, he believes, by
great depression combined with heat, moisture, and pressure. On
examination he found these upper beds everywhere unaltered, except
near dykes, and the change there induced in them was that now
well known as contact-alteration, and which is so entirely distinct
from true metamorphism. These beds all dip to the S.E., and
attain a thickness of several thousand feet. They are flag-like
in character, are made up chiefly of fragmentary materials, and
are occasionally even slightly calcareous. They are much like
some of the Lower Silurian flags in Wales, and are in no degree
more highly altered than the majority of those rocks, especially
in the more disturbed districts. About 3 miles to the east of
Glyn Laggan these beds die out, or at least are lost; and the
Lewisian rocks, fundamental gneiss, hornblende-schists, and mica-
schists, such as those described on the east of Loch Maree, again
come to the surface, and the whole of the remainder of the
section consists of these last rocks, the great mountains Ben Fyn,
Mulart, and others being entirely made up of these rocks without a
vestige of the unaltered beds reappearing there. Of the gneiss,
hornblende-schists, and mica-schists which compose these moun-
tains, it need only be said that, on comparison with others from
Loch Maree, Gaerloch, ete., it is impossible to recognize any dif-
ference in them, the metamorphism being in each case identical in
character, and garnets and other crystals occur in them in equal
abundance. The strike in the beds at Ben Fyn he found also to be
almost identical with those on the west coast, the dip being either to
the N.E. or E., and seldom, if ever, south of that point. He also
found these rocks, and with a similar strike, in the low ground in
Glyn Docherty, near the road to Auchnasheen; and there the
Silurian beds are seen resting unconformably upon them. From
this the author believes that the Cambrian and Silurian beds are
contained in a basin or depression formed of the older rocks, being,
however, now altered in their dip and position by slight faults and
some folding which has taken place since they were deposited.

3. “On the Triassic Rocks of Normandy and their Environments.”
By W. A. E. Ussher, Esq., F.G.S.

Geological Society of London. 329

The author stated that his investigations were confined to the
provinces of Calvados and La Manche, more especially the latter.
Having briefly alluded to the physical areas of the Bocage and
Cotentin, he proceeded to show that whilst the Secondary rocks were
confined to the Cotentin, the presence of several Palzeozoic inliers
proved that they were of no great thickness. He then briefly
described several sections illustrative of observations made by him
in walking over the Triassic districts of Valognes, Montebourg, and
Carentan, and of Bayeux in Calvados. The results arrived at (as
far as possible, despite the presence of drift concealing the Trias
almost everywhere) were that the Norman Trias is composed of
gravel, sands and sandstones, and marls. The gravels replace and
give place to sand and sandstone; but the position of the marls
could only be distinctly ascertained near Carentan, where they
underlie sandstones. The gravels and sands either directly underlie
the infra-Lias, or are separated from it by a thin bed of marl. The
Norman Trias can scarcely exceed 200 feet in thickness.

The author then briefly enumerated the Paleozoic rocks of the
Bocage, and summed up the results of his investigations in the
following conclusions :—

First, that the Triassic rocks of Normandy are the pOUHHscasionty
prolongation of the Triassic area of Somerset and Devon.

Secondly, that Upper Keuper deposits are alone represented in
Normandy.

Thirdly, that fragments of the Palaeozoic rocks of what is now
Normandy were never incorporated in the Triassic rocks of Devon.

Fourthly, that the constitution of the coasts of Normandy, Devon,
and Cornwall is such as to justify a belief that varieties of Cambrian,
Silurian, Devonian, and Granitic rocks formed the bed of the Triassic
waters in the area now occupied by the English Channel, and that
to these sources fragments foreign to the Devonshire soil found in
the Triassic beds on the South-Devon coast are to be attributed.

4. “On Foyaite, an Eleolitic Syenite occurring in Portugal.”
By C. P. Sheibner, Hsq., Ph.D., F.G.S. Communicated by Prof. T.
M‘Kenny Hughes. M.A., F.G.S.

The name foyaite is derived from Mount Foya, in the south of
Portugal, where this rock occurs in the ancient province of Algarve,
intrusive in Devonian grauwacke, where it forms two dome-shaped
hills, the Foya and the Picota, rising respectively to 2968 feet and
2410 feet. The texture of the rock varies from fine to coarse-
grained, and is sometimes porphyritic. An almost compact variety
occurs cutting the coarser rock in dykes and veins. ‘The coarser
rock occurs mainly on the southern slopes, where, however, the
adjoining grauwacke is less altered than elsewhere. The massif is
also cut by intrusive veins of phonolite and basalt of Tertiary age.
Much rock has probably been removed from the district by denu-
dation.

Macroscopically foyaite consists of orthoclase, eleolite, and
greenish hornblende. Orthoclase with imbedded elzolite occurs
porphyritically. A lens shows titanite, biotite, magnetite, and

330 Reports and Proceedings—Natural History Soc. Montreal.

pyrite to be accessories. Microscopically examined, the above con-
stituents are seen to be present, and exhibit considerable variety in
their mode of occurrence, together with nosean and sodalite as
characteristic accessories, and occasional plagioclase (recognized as
oligoclase), muscovite, hematite, and apatite. The elzolite is irre-
gular in outline; nosean and sodalite are often assuciated with and
imbedded in it. The latter minerals are associated and intergrown.
Their mode of occurrence and the tests for their presence are
described in detail. Hornblende and augite occur in foyaite in
about equal quantities, associated and intergrown. These also are
fully described, as well as the characteristics of the other accessories.
Analyses of the elzolite and the foyaite are given. The author
concludes by pointing out the close resemblance of the rock to
ditroite, miascite, and certain syenites of Brevig and Cape Verd,
stating that on this account there is no need of a special group of
foyaites.

Naturat History Socrrry or MontreAt.

At the last regular meeting of the Society for the season, held
April 29th, notes by Principal Dawson were read on some recent
discoveries in Canadian Geology and Paleontology. Some of these
related to specimens collected by Lieut.-Col. Grant, of Hamilton, in
the Niagara (Wenlock) formation. Among these are a great
number of Graptolitic forms belonging to the genera Deitzmania and
Inocaulis. Many new sponges of the Hexactinellid type, belonging
to the genera Astylospongia and Aulocopina, and a large Pterygotus,
“comparable in size with the great Pterygotus Anglicus of the
Devonian of Scotland, though of much greater geological age.
Some small species of Pterygotus have been described by Hall from
the Waterlime formation of New York, and a fragment of an unde-
scribed species has been found by the same paleontologist in the
Clinton ; but the present is, so far as known, the first example of a
large and well-developed species of this genus from so old a
formation. Col. Grant hopes to obtain additional remains. Jn the
mean time the well-preserved maxilliped or ectognath exhibited,
with rounded scaly basal part and narrow maxillary process with
about 12 denticles and 84 inches in length, is sufficient to indicate
the existence of a new and large species, which may for the present
be named P. Canadensis, and which was a Canadian predecessor of
P. Anglicus.”

Among recent facts relating to the geology of the Maritime
Provinces of Canada, reference was made to a “ new classification of
the post-Pliocene deposits, and more especially the recognition of a
layer between the typical Leda clay and the Saxicava sand corre-
sponding to the Udevalla beds of the Swedish geologists, and which
he proposed to name the Upper Leda clay. The Lower Leda clay
contains only a slender fauna of highly arctic species, and corre-
sponding to those found in the permanently ice-covered waters of
Spitzbergen and Baffin’s Bay. The Upper Leda clay holds a very
rich fauna of Northern or Boreal type, but nearly related to that of
Labrador at present.”

Correspondence—MUr. D. Mackintosh. ool

Allusion was also made “to the greater certainty introduced into
the classification of the older formations, which enabled equivalents
to be recognized of the lower, middle and upper Cambrian of
Europe, and which also showed that the older Cambrian rocks had
been partially changed into gneiss and mica slate with andalusite,
and that a large part of the Silurian period is represented in the
Acadian provinces by volcanic rocks, quite dissimilar from the con-
temporaneous beds of the typical “ New York Series,” and more
resembling the English Skiddaw and Borrowdale rocks, while they
often have a very close resemblance to the older Huronian series
which exists in their vicinity.”

CORRESPONDENCE.

REPLY TO MR. USSHER AND H.E.H.

Sir,—I should not have troubled you with a reply to Mr. Ussher
were it not called for to prevent misunderstanding. J know nothing
of the age of the clay with flints, nor of the amount of denudation
which has occurred since its formation. While in Devonshire I was
under the impression that the gravels capping Blackdown extended
(unchanged in character) some distance down the slopes into the
valleys, and that the gravels with erratics on the summit of Little
Haldon extended continuously some distance downward on both
sides, and, on the east side, in patches as far as the sea-coast, in a
manner to me inexplicable by subaérial re-distribution. I thought
these gravels might possibly represent a part of the glacial drifts of
the N.W. and E. of England, and I now think it possible that the
older Devonshire gravels described by Mr. Ormerod, and lately in an
able paper by Mr. H. B. Woodward (Q. J. G. S. vol. xxxii.), may
have been accumulated during a part of the glacial period of the
N.W. and E. of England. Mr. Woodward’s sections very strikingly
remind one of the mode of distribution of the glacial drift of the
N.W. which more or less conforms to the slopes of the valleys and
hills, and which is more a wrapper than a leveller of pre-existing
surface-inequalities. Of the age of these older gravels relatively to
the “ Head” I cannot offer an opinion, but I have little doubt that a
part of the glacial period of the N.W. is represented by the ‘‘ Head”
described by Mr. Pengelly, which covers or rather covered (for it
has been very much tampered with by man) the Miocene lignite and
clay of the Bovey basin. This ‘‘ Head,” which contained Arctic
plants, and great numbers of undoubtedly ice-borne boulders (one of
them 4 feet in average diameter (1867), has undergone an amount
of fluviatile and estuarine denudation extremely insignificant when
compared with the excavation of the Valley of the Exe or of the
pre-Miocene Bovey valley. The fact that the “Head” covers the
raised beaches of the S.W. of England does not prove its post-
glacial age, because the date of these beaches relatively to those of
the N.W., and indeed of the latter relatively to the glacial period or
periods, is far from being certain. Mr. Godwin-Austen long ago
regarded the former as, in one sense, pre-glacial. From the Land’s

O82 Correspondence—Mr. C. Callaway.

End to Weston-super-Mare the raised beaches are more or less
covered with “Head,” which often contains large and undoubtedly
ice-borne boulders. Under the raised beaches of the W. coast of
Cornwall and Devon, traces of an older deposit with ice-borne
boulders may occasionally be seen, as 1 have been informed by Mr.
Whitley of Truro, who has had very extensive opportunities of ob-
serving these phenomena. The raised beaches themselves sometimes
contain very far transported erratics (washed out of an older
glacial deposit ?).

In answer to H. EH. H., it ought to be remembered that, in Sir H.
de la Beche’s day, the effects of glacial action were but little under-
stood, and it is probable that he never saw sections of curved
laminee like those which of late years have been exposed by exten-
sive quarrying and mining operations. JI would refer H. H. H. to
the very able defence of the glacial origin of persistently curved
lamine by Mr. Tiddeman in the Q. J. G. 8. vol. xxviii. p. 480.

D. Macxinrosu.

ON THE FAUNA AND AGE OF THE SHINETON SHALES.

Srr,—I was glad to see in your April issue a letter by Dr. Lin-
narsson on the Trilobites of the Shineton Shales, as I am desirous
that my conclusions should be tested in every possible way. I have
carefully reviewed every detail to which he has suggested exception,
and beg to submit a brief reply to his criticisms. His statements
are the following.

1. Conocoryphe monile is more nearly related to Angelin’s genus
Euloma than to Conocoryphe striata. |

To this I demur. uloma is described by Angelin as covered with
a smooth crust, and with pleure acute, and bent back at the ends. C.
monile has a granular surface and blunt pleure. I submit that these
are more important characters than the “ strongly-lobed glabella
and the dotted marginal furrow,” in which C. monile is supposed to
resemble Kuloma. C. striata is larger than C. monile, has the glabella
more conical, and with a third pair of side furrows, and has the
frontal margin undotted, but on the whole the two species are of the
same type.

2. Lichapyge is more closely allied to Remoplewrides than to
Lichas.

To this also I cannot agree. Dr. Linnarsson assumes that in my
genus the “two hindermost thoracal segments” are united with
the pygidium. If he were to examine my specimen, he would see
that it consists of one undivided piece, and is therefore a pygidium
only. This being so, it cannot be related to Remopleurides. It re-
sembles Lichas in the number of segments (three), and in the shape
of the pleure; but differs in the telson, which in Lichas ends in two
denticles, while in Lichapyge it forms a broad sword-like blade with
a central point.

3. Platypeltis is more nearly related to Niobe than to the typical
Asaph.

I myself called attention to this point on page 659.

Correspondence—MUr. 8. G. Perceval. 333

4, Conophrys is probably the same as Shumardia, Billings, and as
Buattus pusillus, Sars. ;

I can say nothing to this, as I have been unable to obtain the
published descriptions of the forms referred to.

Dr. Linnarsson seems to infer from the presence of Conocoryphe
monile that the Shineton Shales are Upper Tremadoc. Even if his
opinion of the affinities of this species were correct, we could not’
ignore the presence of two species of Olenus, of Dictyonema sociale,
and of other Cambrian forms. Nor must we overlook the fact that
in the Malvern district the Shales with Dictyonema immediately
overlie the black Olenus Shales. I think that, with our present
evidence, it will be safest to correlate the Shineton Shales with the
Lower Tremadoc. I have just had the good fortune to detect them
in force between the Longmynd and the Stiper Stones, the higher
beds forming the base of the Stiper Stones escarpment. The dip is
in the same direction as the overlying Arenigs; but towards the top
of the series (where it grows more arenaceous and flaggy, as in the
Shineton area) the beds are contorted and much jointed. I will
not venture upon theory on the strength of one hour’s work. It is
gratifying to find my previous evidence from fossils so clearly con-
firmed, and to throw in the teeth of the unbelieving stratigraphists
another proof that paleontology is not quite exploded.

WELLINGTON, Satop, May 9th, 1878. CHARLES CALLAWAY.

ORTHIS REDUX IN MIDLAND BUNTER PEBBLES.

Sir,—In reply to the letter of Mr. J. H. Jennings in the May
Number of the Grou. Mac. it may interest him to know that the
Rev. P. B. Brodie has drawn attention to the occurrence of fossili-
ferous pebbles in the drift near Warwick similar to those which
occur at Budleigh Salterton, in the Quart. Journ. of the Geol. Soc. of
London, vol. xxiii. (1867), p. 210.

The Drift of the Midland Counties is mainly composed of the
redistributed Bunter Conglomerate, a formation which, as far as the
pebbles which it contains are concerned, is lithologically and pale-
ontologically identical with the Conglomerate of 8. Devon. The
stratigraphical position and relation of the two deposits, so far as I
have examined them, in both districts appears much the same.

In the Museum of the Midland Institute is an extensive series of
Bunter material, collected from the gravel around Birmingham,
which I presented in 1872 to the Birmingham Naturalists’ Society,
as well as of specimens for purposes of comparison from the Bunter
Conglomerate itself. In 1875 I gave a beautiful series of fossili-
ferous pebbles to the Jermyn Street Museum, also from the Birming-
ham Drift. Orthis redux is, as at Budleigh, one of the commonest

fossils. SPENCER GEORGE PERCEVAL. .
Hensury, Bristor, May 11, 1878.

WHAT IS AN ERRATIC?
Srr,— Under this title, in your April Number for the current year,
my esteemed colleague, Mr. Wynne, argues that I am wrong in
restricting the term to fragments which have been transported by

334 Correspondence—Ur. W. Theobald—Mr. A. B. Wynne.

ice, and maintains that it is equally applicable to pebbles and
boulders, instancing the flints on the Irish coast and the constituents
of the Chesil Bank as erratics, in his sense of the word. If the
bulk of geologists agree with Mr. Wynne in this, I confess I shall
feel surprised. Mr. Wynne also disputes certain views of mine
touching minor details of geology in the Salt Range, but it is not
‘my intention to notice these, as, the ground being unknown to the
bulk of your readers, the discussion would be both tedious and
unprofitable.

In justice to myself, however, I cannot permit the second para-
graph of Mr. Wynne’s letter to pass unchallenged, as it contains a
complete and incomprehensible misapprehension of my meaning.
The passage runs thus: ‘In these remarks,’ Mr. Theobald restricts
and applies the term ‘ Hrratics’ exclusively to certain blocks sup-
posed to have been ice-transported, advocating the idea also (vide
foot-note) that the word is only applicable in describing recent phases
of geology.”

Of course I neither said nor meant any such thing as the extra-
ordinary statement I have italicised above. What I did say was:
‘‘Under these circumstances, therefore, I do not think that these
red granite boulders can be termed ‘ erratics,’ unless we fall back on
the hypothesis that all of them have been erratics during a former
and wholly different phase of geological life than that which we at
present have to describe and deal with.” (J.c.)

Now I deny that my words can fairly be twisted so as to yield
the extraordinary sense, or rather nonsense, which Mr. Wynne
attributes to me; and had my MS. not received some mutilation
(unknown to me) in passing through the press in Calcutta, this
misapprehension of my colleague could hardly have happened. I
originally wrote some such explanatory sentence as the following :
‘Unless on the principle of once a parson always a parson, we hold
that once an erratic, always an erratic.” Of course the Chesil Bank
boulders may at one time or another have been erratics; but wnless
on the principle of the above proverb, they can, I think, be termed so
no longer.

As this is the exact opposite of the ridiculous view Mr. Wynne
fathers on me, I wish to repudiate the mistake in the same pages
wherein it appears, to my great discredit if uncontradicted.

Marreg, Pansas, May 13th, 1878. W. THEOBALD.

WHAT IS AN ERRATIC ?

Si1z,—I should have called attention in the second paragraph of
my letter, in your April Number, 1878, p. 185, to the passage in my
friend Mr. Theobald’s remarks which reads thus: ‘‘ Under the head
CDT) ¢ 55%, 40 my colleague describes others, which are not
only, in my opinion, not ‘erratics’ at all, but belong to diverse
geological epochs.”

This, together with his footnote, to which I referred, left the
impression that, according to him, ‘“erratics” must belong to but one
and that a recent geological epoch. A. B. Wynne.

1 Records of the Geological Survey of India, yol, x. part iv. p. 223.

Oorrespondence—Mr. S. V. Wood—Mr. W. Davies. 385

PHYSICAL GEOLOGY OF THE PUNJAB.

Str,—Will you allow me to make a few corrections in your
abstract of my short paper to the Geological Society (Gzon. Mace.
Dec. II. Vol. V., No. IV., April, 1878, p. 181.)

Line 1 for ‘accession’? read “ accessible.”

», 12 for ‘‘on limestones ”’ read “ are limestones.”
», 14 for “ Lei Bau” read “ Sirban.”

», 26 between when and present insert “ both are.”

», 28 for “ further east a” read “ further east, in the Salt Range a.”

A. B. WYNNE.

SUBGLACIAL ORIGIN OF TILL.

S1r,—Mr. Geikie writes you that “I quietly ignore all the posi-
tive evidence “ which has been adduced in proof of the subglacier
origin and accumulation of the chalky Till of Suffolk.”

I know of no such positive evidence.

Per contra. Why does Mr. Geikie so quietly ignore the positive
evidence of marine conditions afforded by the thread of sand, packed
with the remains of marine mollusca with valves adherent, which
was discovered by Prof. T. M. Hughes and Mr. L. Lyell in the
midst of the chalky basement clay of Holderness, which is similar
in character and structure to the chalky clay of Suffolk ?

S. V. Woop, Jun.

ERRATUM.

Srr,—Not having had the opportunity of examining the drawings
of Plate VIII., in the June Number, before the stone was etched,
allow me to call attention to some points in which they are defec-
tive. In Fig. 1 the oblique foraminal notches are not defined,
these are an important character, and are clearly shown upon the
fossil ; again, Fig. 2 does not give the entire outline of the mandibu-
lar ramus, which is well represented upon one of the blocks, inas-
much as the artist has omitted in his drawing the imperfect angular
and articular bones preserved upon it, and it is consequently half an
inch too short. The enamel of the teeth is finely plicated on the
cutting edges, but the teeth are not crenulated, as the drawing of
the plications on the enlarged Figure 2b might suggest. Finally,
in “ Explanation of Plate,” Fig. 26, for inner read antero-posterior.

Wm. Davies.

Hrratum.—We are are requested to make the following correction
of the notice of Prof. M‘Coy’s “‘ Victorian Organic Remains” (Decade
V.) given in the June Number, see p. 284, lines 5 and 6 from top:—

Substitute for “whether the supposed Mesozoic genus Belemnites may,” etc.,

“whether the Mesozoic genus Belemnites supposed to occur in the Australian
Tertiaries may,” etc.

836 Obituary—Olarke, Daintree, Hartt, Heatherington.

@iS7Eae WPAsEays

————_>__

REV. W. B. CLARKE, M.A., F.R.S., F.G.S.

We are sorry to learn the death of this distinguished Australian
geologist at Sydney, New South Wales, by telegram, on June 17th.
—Nature. (We hope to give a full notice of Mr. Clarke next
month.)

RICHARD DAINTREE, C.M.G., F.G.S.

Tur Standard, June 24th, 1878, announces the death of Mr.
Richard Daintree (late Agent General for Queensland) on the 20th
June, at his residence, Holyrood House, Beckenham, Kent. Mr.
Daintree’s death will be deeply regretted by a wide circle of geo-
logical friends. We shall give a notice of Mr. Daintree’s geological
works next month.

PROFESSOR C, F. HARTT.

Tuer mail from New York brings us the sad news of the death of
Prof. Charles Frederick Hartt, of Cornell University. He died on
the 19th of March last of yellow fever at Rio Janeiro. Prof. Hartt
at the time of his death was in charge of the Brazilian Geological
Survey; he was a native of Frederickton, New Brunswick, having
been born there in 1840, but it was in Nova Scotia where he
first followed geological pursuits. After having been a student
under Prof. Agassiz from 1862 to 1865, he accompanied that gentle-
man to Brazil with the Thayer Expedition in the latter year. The
account of this and a later journey he embodied in “Scientific
Results of a Journey in Brazil—Geology and Physical Geography
of Brazil,” Boston, 1870. Prof. Hartt was a diligent student of
Indian languages and folk-lore, and not long since published at Rio
a brochure on the “Hare and Tortoise Myths of the Amazonian
Indians.”

ALEXANDER HEATHERINGTON, F.G.S., ETC.

Ir is with regret that we record the death of Alexander Heather-
ington, Hsq., F.G.S., late of Halifax, Nova Scotia. He died at Toronto
on the 8th of March last, of pleurisy. The province of Nova Scotia
owes him a debt of gratitude for his persistent efforts to promote
her progress, and bring her to the front as one of the first gold-
producing countries of the world. He was a clever statistician and
the author of “A Practical Guide for Tourists, Miners, Investors,
and all persons interested in the Gold Fields of Nova Scotia,” and
“Mining Industries of Nova Scotia, a Review of the Gold Field
from 1860” to 1878, 1875, etc. He was editor and proprietor of
the “Mining Gazette,” published at Halifax, Nova Scotia, a few
years ago.

New SERIES. DECADE II VOL.V.PLATE Ix.

4.6 47
5.55, z 5.15

*

665

ah
B55 29 4 8.65

19.25

mia
LIL

Profile of Volcanos traced from Photographs.

Measurements in Millimetres

Yo wllustrate Prof. John Milne's Paper.

IT Milne del W. West & C2 lak

THE

GEOLOGICAL MAGAZINE.

NEW SERIES. DECADE llk7 VOE. V,.
No. VIIL—AUGUST, 1878.

@ieu GaN Asse) Aveiro ate sls @ ae 2b SS.

—@___
I.—On tHE Form or VOLCANOS.

By Professor Joun Mitnz, F.G.S.,
Imperial College of Engineering, Yedo, Japan.
(PLATE IX.)

ROM the short notices which are to be found about volcanos in

treatises on geology, we might often be led into the belief that
they were structures so regular in contour that their form was
indicative of their nature. In certain cases this appears to be so
remarkably true, that I wish to add a few observations to those
which have already.been written upon the subject. In other cases,
however, the form of a volcano does not appear to have any character-
istics which distinguish it from other mountains, as will be seen by
glancing through the series of views given by Humboldt of the
volcanos of South America. The mountains in Iceland are also
very rough. When travelling in that country, where I saw and
ascended many volcanos, I do not remember that there was any-
thing about their shape more than their steepness and general
ruggedness which particularly attracted my attention.! The wilder-
ness of form presented to us by such mountains as these is so
evidently the combined effect of many and varied causes, that it
would be vain to seek a simple explanation for the formation of the
whole.

With other voleanos which have been built up according to the
formula of our text-books, that is, by the ejection and accumula-
tion of material round a central vent, the case is different. I will
endeavour to show that such mountains which, for the want of a
more accurate term, have been called conical, have a particular kind
of regularity which does not appear to have been hitherto noticed.
Conversely, I wish also to point out, that if this particular form is
observed, that from it, not only is it possible to state how the
mountain has been built up, but also from any variations in this
form to determine the presence and dimensions of an internal core.
For these purposes I shall take the mountains which I have had the
opportunity of observing since my residence in Japan. The first
point to be observed about many of these mountains is the regularity

1 This, however, is a statement made from memory, for shortly after my return
to England, my Icelandic sketches and note-books were unfortunately lost.

DECADE II.—YOL. V.—NO. YIII. 22

338 Prof. J. Miine—On the Form of Volcanos.

of their contour, and secondly the fact that these contours appear to
be similar. Pre-eminent amongst the regularly formed volcanos of
Japan with which I am acquainted I may mention Fusiyama, 12,365
feet, near Yokohama; Ganjosan, 7000 feet, near Morioka; Chokaisan,
6000 feet, between Niigata and Akita; Twakisan, 5000 feet, near
Awomori; and Kumagatake, 2700 feet, near Hakodate.

If we look at the profile of these mountains near their summits,
we might be inclined to call them conical; but if we look at them
as a whole, as we descend we see this upper cone expanding and
sweeping outwards, forming a graceful curve. The causes which
might produce or subsequently affect this form may be summed
up as follows.

1. The position of the crater. If this is central and remains in that
position during successive eruptions, we may expect the mountain
to be regular in form.

2. If the eruptions of a mountain are irregular in their action
and character, the above regularity may be destroyed. Thus by
paroxysmal outbursts portions of a cone might be removed,—if
lava is erupted at one time and not at another, or if it accumulates
on one side of the mountain more than on another, these are all causes
which would seriously interfere with any regularity of contour.

3. Any outbursts on the side of a mountain, or formation of
parasitic craters, will also tend in the same direction.

4, Hven if the crater should be central, but the direction in which
the lapilli and other materials were projected should be towards one
side more than another, as I sometimes observed was the case at the
eruption of Oshima in 1877, the regularity of the piling up will
also be interfered with.

5. The direction of the wind during an eruption will also in-
fluence the shape of a mountain. On the Yedo side of Fusiyama
the slope is less than upon the opposite side. This I believe is in
part due to the wind, which at the time of the last eruption of that
mountain, in 1707, was blowing in the direction of Yedo.

6. The nature, that is, the size, the specific gravity, the porosity,
etc., of the materials thrown out will during the actual accumulation
and subsequent consolidation give a character to the curve of the
slope.

7 . Lastly, we have the effects of denudation continually drawing
material to lower levels and sculpturing and modifying the original
contours. As this action will generally take place more or less
uniformly on all sides of a mountain, it will be a cause tending not
so much ‘to destroy the regularity of a volcano as to alter the
character of its slope.

When considering the various causes which may produce denu-
dation, we must remember that there generally will have been more
action near the summit of a mountain than near the base. Thus, for
example, more water falls at the top of a mountain than below, and
therefore the little streamlets which cause disintegration will be
more active at the top of a mountain than at the bottom—the activity
diminishing gradually towards the base. One of the tendencies of

Prof. J. Miine—On the Form of Volcanos. 309

such an action is to make a mountain steeper near the top than lower
down, an appearance which will be again referred to.

If we wish to discover an explanation for the differences which
exist between the characters of the volcanos of two countries like
Iceland and Japan, it is not to the effects of denudation that we ought
to look, for denudation in the case of the volcanos of these two
countries, which are either now in action or else have been so within
periods which are almost historical, might, I think, be taken as being
equivalent to each other. We must rather look to the nature and
the products of the eruptions. In Iceland I suspect that the out-
bursts have been more paroxysmal, whilst the number and extent of

lava flows are perhaps unrivalled. These causes have given a ragged

wildness to the country and its mountains. In Japan, however,
lava streams, although existing, are by no means numerous, and the
mountains, which far exceed the height of those in Iceland, must,
generally speaking, have grown gently upwards like a heap formed
by sand falling through a funnel upon a level floor. In consequence
of this it will be shown that they have in many cases assumed a
form as symmetrical as any which would be expected in an en-
gineering earthwork.

Slopes of Volcanos.—lf we look at the cuttings along a railway,
we shall see that their slope varies with the material through which
they are run. When the material is loose and friable, the slope is
more gentle than when it is tenacious and has much friction amongst
its particles; for example:

For compound earth the natural slope is... 50°.
» gravel i a eed aeten Wire T resawel (cas tates 40°.
», dry sand a Bs Se Maen ig hemes Wit 38°.
>, sand on ss a6 staat MaLeos 22.
», wet clay . bn it Ae hei sigue 16°.

When climbing up the sides of volcanos I have invariably observed
that the materials resting upon any particular slope are uniform in
size; and if we take a piece of lava or lapilli which is larger than
the other particles, and throw it upon such a slope, we see it com-
mence to roll rather than remain at rest. From this it appears that
we ought generally to find the large pieces of material which are
ejected from a volcano upon the more gentle slopes near to the base
of the mountain. The reason of this evidently lies in the fact that
friction depends on surface, and weight depends on volume, and
that as bodies are made smaller and smaller the ratio of their surface
to their volume increases more and more.

Should we be desirous of making any investigation respecting the
slopes upon the face of a long escarpment, or the face of a broad
chain of mountains, the theory and rules given by Rankine in his
Investigations about Harthworks might be applied. In a volcano
or solitary mountain, such as those which are now referred to, the
conditions would be somewhat different, as we have to consider the
stability of a mass of material with a variable radius, whilst in the
former case the radius might be regarded as being infinitely long.
As there does not appear to be any formula given in books on
engineering, respecting the slope or form which would be assumed

340 Prof. J. Milne—On the Form of Volcanos.

by a heap of loose dirt, an engineering friend has shown me that
it follows from Rankine’s theory, notwithstanding that the same is
incomplete, that the surface is that which would be produced by a
simple logarithmic curve revolving about an axis,—consequently
such a heap would have a slope diminishing from the top to the
bottom. Looking over my note-books, amongst the steepest slopes
which I have observed upon the sides of volcanos in Japan, I may
mention the following: Fusiyama, 30°; Asamayama, 28°; Ganjosan,
31°; Twakisan, 80°; and Kumagatake, 40°. The first four of these
are outside slopes taken near the top of the mountain. The last
observation was made upon a slope of angular blocks of stone
inside an old crater.

Mr. Scrope gives the slopes of volcanos as being from 20° to 35°,
towards the base diminishing to 10°, and gradually ultimately to
horizontality. However, whilst fully recognizing the nature of the
true slope of a volcano, the sketches which illustrate works treating
of this subject are, so far as can be judged by rough measurements,
somewhat misleading. For example, to quote from the pictures in
the works of no less a person than the great Humboldt, “‘ Umrisse
von Vulkanen aus den Cordilleren von Quito und Mexico,” I find
that, by rough measurement, the slopes of several voleanos must be
as follows: — Cayambe Uren, 18,170ft., about 53°; Elcorazon,
14,820ft., 58° to 69°; Chimborazo, 17,712ft., 55°; and Ilinissa,
16,862ft., 55°. Whether these Matterhorn-like inclinations really
represent reality or not, I do not know, but I should be inclined to
think that artistic feeling may have caused them to have been
unintentionally augmented.

Form of Voleanos.—The general form of a volcano has already
been suggested whilst speaking of the inclination. To quote more
fully from Mr. Scrope, he says, “It should be remarked, however,
that the dykes being more numerous near the central vent, their
aggregate effect in elevating these beds will be greatest there, and
give them a steeper elevation near the summit than lower down the
flanks of the mountain. This is one cause (but by no means the
principal one) of the angle of the slope of the higher beds, and of
the outer slope likewise, usually ranging from 20° to 35°; while
towards the base it diminishes to 10°, and graduates ultimately to
horizontality. The more influential causes of this general result
are (as will shortly be shown), the frequency of lateral eruptions on
the lower slopes of every volcanic mountain, loading them with
parasitic cones and floods of lava, and the abundance of fragmentary
matter carried down the heights by rain and floods—all combining
to enlarge the base.” ! Whilst fully agreeing with the form which
is here described, the causes which are indicated as having been the
principal ones in the production of such a mountain form, although
no doubt, influential, are, I should think, by no means the principal |
ones. Of the greater number of volcanos which I have seen in
Japan, the only method which I have had of obtaining their general
form and curvatures has been by sketching. Of two of them,

1 Scrope, Volcanos, p. 167.

Prof. J. Miine—On the Form of Volcanos. d41

Fusiyama and Kumagatake, I have been able to obtain large photo-
graphs,—of the former no less than thirty different views. As these
pictures, which have a slight distortion due to perspective, were the
best representation of the true form of a volcano which I could
obtain, it has been assumed that they are correct, and they have
been used in determining the shape of the mountain in the following
manner. To investigate the form of these mountains it was first
required to find an axis for them, which was attempted by drawing
verticals through some objects, and their reflections, which happened
to have been photographed in the foreground of one of the pictures.
Afterwards it was found better to make tracings of the photographs,
which were doubled until a greater portion of the profiles coincided,
and then to take the crease in the paper as being the median line
and axis.

Enlarged drawings made by a pantograph were also used, but
these were found not to be so convenient as the tracings from the
actual photographs which are represented on the accompanying
sketch. In the cases which are represented, with the exception of
one or two slight excrescences which are shown by shading, the
profiles are coincident with a free curve. Whilst looking at these
profiles it must be remembered that any apparent differences in
curvature, which may be observed, are due to the fact that one
profile may represent only the upper portion of a mountain, whilst
another may give a view from the summit to the base. Thus, for
example, profile No. I. only shows the upper portion of profile No.
II. The next thing which was done was to draw a series of ordinates
at 5™™ apart, the length of each of which r, was accurately measured,
and may be seen in the first columns of the following tables. In
the second column, the sum of each successive pair of these ordinates
& is given, and in the third column their differences dr.

Now it is found, as will be seen by looking at the fourth column,
that 2 is equal to a number which is nearly constant, which is the

peculiarity of a Logarithmic Curve.

ProFiteE No. I. Plate IX.
Fusiyama, from near Marajama. S.W. side.

Lert Sipe. Riagut Sipe.

: R di & 2 R ak =
pee | 10,15 uno a.10;67 Aye 10:25 OF OOS
Piraau 1lG SO ama TOMae 16,85 Pearle A uae COME
Se ISTE TS cee Mee 10S 188
Cee TO Ts EE CO TOE 0B Tae

18-40 1:10 16°72

ieee 20°50 1:30 15-76 nee BORE TO)
spy | sO), UTES STATS See Oey | TNR TA
sean OSD Tea TRO veep DEI. TBs
say OH. Te. Tae eee SIE BB BOE
Teh mm oz Bonem2 lpn tna 27 Sonn adem TRAE lear
chiepi 8/200 S:20 9 Nico He, | See URE Bale
sos Ges ana One

40°25 1:75 22:00

042 Prof. J. Milne—On the Form of Volcanos.

ProrintE No. II. Plate IX.
Fusiyama, from near Hitoana. West side.

Lerr Sipe. i Rieut Sipe.

, R

: fase R . Sy

t R dr dr % th dr
BARE aN ay ra SO aaranile hieBo)) 53m
9-95 5°00 90 5:55 3°50 6:05 "95 6°36
ine 6-80 -90 7°55 hee 8:05. 1:05 7-66
4°85 8:70 1:00 8:70 5:55 10:10 1:00 10:10
5-85 10°70 1:00 10°70 6-65 12°20 1:10 11:10
7-00 12°85 1:15 11:17 7-90 14°55 1:25 11°67
8-40 15:40 1°40 10°71 9-30 17-20 1:40 11:28
10:10 18°50 1:70 10°88 11:95 20°55 1:95 10°50

12°30 22°40 2°20 10:18 1380 25:05 2°55 9-807

14-20 26°60 1:90 13°94

ProritEe No. II. continued.
Profile No, II., with other ordinates, gave upon the left side the following -—

r R dr AB
Boe 4-825 “895 5:8
ree 8-525 975 8-7
Pee 10-550 1-050 10-0
oe 12-675 1-075 11-7
HS 15-075 1-325 11°3
Sak 17-900 1°500 11:9

ae 21-300 1-900 11-7
i ee 25-600 2-400 10°6

I omit the right side of the profile because on that side there is a
distortion due to the last eruption in 1707, which was a lateral one.

ProritE No. III. Plate IX.
Fusiyama, from Suyama and Gotemba. South-east side.

Lerr Sipe. Ricut Spe.
R R
R dr aa r R dr ae
Bp gi86+ |) 95 (og Rep PMI Miss55ih Minors Mas LOS
a GO| OD) GR Foy iit 1 «5p60) LOO RN yh aeRO
se MMARTGOG MINN 95), Nnh7,640 BP i260 4 1,00) TCD
Fae 260. «90. «10-660 SN INCH NeW) SEL
oeel 1 (lSoia iy ote 1 102800 Pray) WOR 1B O88
Sa ao ERD) ie
102.) ial Ola ial ae ese
aan 1) OO) Usa eat

24°00 1:40 10:00

Prorite No. IV. Plate IX.
Kumagatake, as seen when approached from Hakodate.

Lert SpE.

R

R dr a

r ar

AE 0-25 0:25 5
i 1:50 1:30 1:15
0-15 3°50 75 4:73
ae 5-20 90 5-78)
oe 7°30 1:20 6:08
5-80 10°05 1°55 6:48
Sea 14:40 280 514
11:40 20:00 2°80 714

Prof. J. Milne—On the Form of Volcanos. 343

The right side is left out, because it is so very irregular.

No. V. is not calculated, because it is probable that the only
photograph which I have may have been taken from a picture. It
is, however, useful as showing, as compared with the others which
are drawn, a similarity in curvature. |

Considering that these investigations have been open to so many
errors, the picture being a perspective view, it being small and
difficult to make measurements upon, there being no accurate method
for obtaining a true axis, there being many small irregularities in the
mountain itself,—the fact that the calculations made from different
pictures should all so closely approximate to each other is evidence,
I think, sufficiently converging for us to accept the result towards
which it points.

That this result should agree with that obtained for the stability of
a self-supporting mass of loose materials is very striking, and seems
to show, notwithstanding its roughness and the observations to
which it has been applied, an invariable concurrence.

This being the case, I think we are justified in regarding mountains,
similar to those about which I am now writing, as having a form
maiuly due to the simple piling up of material, and not as cones
which have been subsequently modified by a number of secondary
causes, such as are advocated in treatises on Physical Geology and
Volcanos.

Probable Existence of an Internal Core.—Observing that the slight
discrepancies which do exist in the values of 2 are due to variations
in the curvature near the top, and at the base of the mountain it was
suggested that these might not only be due to external modifying
and sculpturing actions, like those pointed out by Mr. Scrope, but
also, perhaps, to the action of an internal core. If we pour sand
upon a table, it ought to form a heap, with sides like those of a
Japanese volcano; but if we first place a small box on the table, and
pour sand on the top of it until it is buried, the shape of the heap
will be considerably altered. If, instead of a box and sand, we take
a mountain like Fusiyama, and imagine it to have a core which is
tolerably flat, such as we might have expected from the more modest
of the advocates of an elevation theory, the result would be that the
present base of the mountain would be considerably contracted,
because in this case the core is capable of resisting a greater pressure
than an equal bulk of cinders could resist. Above the core the
curve would be logarithmic, from which we may conclude that if
any core exists in the mountains about which I have been writing, it
is probably below the lowest line at which measurements have been
made. To enter fully into the effect which a core would produce
upon the external form of a mountain, is a calculation into which
friction would enter as an important factor.

If, from the shape of any given mountain, it were supposed that
it had been built up round a more or less cylindrical core, it would
be interesting to calculate the diameter of this core for various
heights. ‘This also can be shown to be logarithmic in form.

Building up of a Volcanic Mountain—The eruption at the island

344 Prof. J. Miine—On the Form of Volcanos.

of Oshima, of which, in 1877, I was a close spectator, commenced by
the throwing up of ashes from a fissure which had for several years
previously only given vent to steam. At the time of my visit a
quantity of these had accumulated to form a heap of a certain
height. The form of this heap was to all appearances similar to that
of the larger mountains. For this heap to increase in height, so long as
the plane on which it rested was approximately level, it was necessary
that it should also increase the diameter of its base. Now, if the
sides of a volcanic mountain have slopes which are always loga-
rithmic curves, and if we assume that the area of the top is always
some fraction of the height, the relative rates at which the height
and the diameter of the base increase can be easily calculated,—and
if we have given the height of a mountain, we shall, under the
given circumstances, be able to determine the diameter of its base.

The eruption at Oshima has now ceased, and the materials which
have been ejected may be regarded as the nucleus of a small
mountain. By such causes as the action of its own weight,
infiltration, etc., this mass is now gradually becoming consolidated.
As this embryonic mountain is of the best possible shape to resist
the effects of denudation and weather generally, from wearing much
from its sides, this consolidation will leave it in a form not very
much unlike that in which it was first raised. Should a second
eruption take place from or near the old crater, it will have to pile
material on this hardened nucleus, which, being stronger than a mass
of loose ashes, will act like a box beneath a heap of loose sand,
rendering the mountain generally steeper.

We have evidently here in certain cases a rough test as to whether
any mountain has been produced by one or more large eruptions,
and at the same time an insight into the probable method by which
many volcanic mountains have been raised.

Where there have been many overflows of lava, these may have
consolidated like ribs or buttresses on the sides, and have tended to
make the nucleus still stronger, and, therefore, prepared after the
next eruption to support material at a still steeper angle.

As the mountain increases in height, its weight, as pointed out by
Mr. Mallet, probably produces a depression in the base on which it
rests, this being greatest under the apex of the mountain, where the
pressure is greatest. The ultimate result of all this will be that the
mountain will tend to rest in a saucer-shaped hollow, and to have its
lower beds dipping radially towards a centre. If this action should
have taken place in any mountain, it might at first sight be con-
sidered as influencing the external form of the mountain, and
consequently any deductions which have been drawn from such a
form. However, we must remember that this sinking will, as com-
pared with the mass of the mountain, be small, and, also, it will be
gradual, so that, without appealing to calculations, I think it will be
admitted that the accumulation of material will more than counteract
such an action. Even should there be a sudden collapse beneath a
mountain tending to produce any inequalities on its external surface,
these inequalities will represent material in an unstable position,

H. E. Hippisley—Somersetshire Coal-measures. 345

which will gradually give way before the tendency which the ~
mountain will always have, namely, to assume that position in which
the materials are best arranged to afford to each other a mutual
support, and this position appears to be that of the logarithmic curve
which has been described.

We have not yet considered that these mountains have to support
anything but their own weight, but as Rankine has shown that the
logarithmic form is the best for revetement walls, or walls of re-
servoirs, etc., without going into calculations, it will be evident that
these regular volcanos are also strong enough to support the pressure
of a column of lava of their own height.

In conclusion, I may remark that just as it is possible that the
fiery mountains and earthquakes of Japan impressed its inhabitants
with wonder and superstition, so the beautiful forms of the volcanos
may have been the first suggestions for the curvatures we see upon
the roofs of houses, and for the massive walls which bound the moats
and support the embankments of all the castle towns. How far this
may be true, I do not know, but certainly the form which has of late
years been shown the most stable for such structures, is one which
in Japan has reached its millennium.

EXPLANATION OF PLATE IX.
Profiles of Volcanos traced from Photographs.
No. I. Upper portion of Fusiyama, taken from near Marayama, 8.W. side.
No. II. Fusiyama, from near Hitoana, West side.
No. III. Fusiyama, from Suyama and Gotemba, S.E. side.
No. IV. Kumagatake, as seen from near Hakodate.
No. V. Monte Somma and Vesuvius.

The shaded portions show irregularities in the curvature of the mountains.
These, it will be observed, are very small

The broken line - - - - on the right of No. II. is a logarithmic curve drawn
for purposes of comparison.

It suggests that No. II. was once logarithmic, but the upper portions of the
mountain have been washed to the bottom to render the mountain less steep
both above and below.

It also might indicate that the phenomena, spoken of by Mr. Mallet, had taken
place, namely, that the weight of the central portion of the mountain had
caused an elevation round the base.

IJ.—SomeRsetsHIRE COAL-MEASURES.
By H. E, Hipristey, M.A., C.E.

le will probably be conceded, by those who have studied the
Somersetshire portion of the British Coal-field, that the cor-
relation of the various parts of it is not, at the present time, so
perfect that any attempts to improve it are entirely uncalled for.
The following conjectures! as to whether some of the facts relied on
as proving the commonly-accepted theory of the structure of the
Somersetshire Coal-measures, and their general correlation with
those in Gloucestershire, may not possibly admit of an interpretation
differing from that usually assigned to them; are put forward in
the hopes of indicating a line of research which may eventually,
when modified by the results of further investigations, lead to a

1 Being a brief summary of an unpublished paper on the subject.

346 H. E. Hippisley—Somersetshire Coal-measures.

solution of some of the numerous difficulties at present standing in
the way of a satisfactory understanding of this extremely com-
plicated district.

The commonly accepted structure in Somersetshire is taken to be
as follows—in descending order :—

1. The Radstock measures, supposed to be wanting in Gloucestershire and stated

to have been removed by denudation there.

. Beds of red shale, traces of which are supposed to exist in Gloucestershire near
the top of the Coal-measures there.

. Farrington measures, supposed equivalent to the Gloucestershire upper series
measures,

. Pennant.

. Lower series Coal-measures.

. Millstone Grit.

. Carboniferous Limestone.

All, of course, more or less disturbed by faults, but still in the above

order; and this general relation of the Coal-measures in Somerset-

shire to those in Gloucestershire is supposed to be thoroughly well

established.

It may be as well to allude briefly to some of the causes which
make these Coal-measures peculiarly difficult to study in such a
manner as to be certain that the results arrived at are free from error.

About five-sixths of the Bristol Coal-field are concealed by newer
formations, rendering it impossible to trace the measures, or the
position of the numerous faults of an older date than these newer
formations, on the surface; the sole information obtainable, when
the Coal-measures are not exposed, being from the workings at the
different collieries.

These workings at different places have in many cases not been
connected by accurate instrumental measurements, but often only
in a vague and general way, and by assuming perfect regularity in
the strata between the separate workings, when perhaps the very
contrary may be the case.

Absence of records showing the full details of pit sections; the
only information obtainable now, concerning many of the older
sinkings, being the simple intervals between the seams. Also,
faults cut through in the shafts do not always appear in the sections.

Correlation of the seams has occasionally proceeded in rather a
haphazard manner, the seams being named first, sometimes without
nearly sufficient evidence as to their identity, and then the names
traced from one colliery to another as if the correlation were un-
doubtedly correct.

The correlation would have been much more reliable if the full
detailed sections had been taken into account instead of merely
fancied resemblances and qualities and thicknesses of the coals
alone, all often extremely variable in comparatively short distances.

The faults of the district are extremely numerous, those shown on
the Geological Survey being, although by no means few, only a
portion of them, complicated, and with throws often very consider-
able, and where the throw of a fault is, as usual, calculated by the
amount of displacement of a seam bearing the same name on each

SIO Oe (Sv) bo

H. E. Hippisley—Somersetshire Coal-measures. 347

side of the fault, it results that if the seams should happen to be
wrongly correlated, the throw of the fault may be very different to
that which it is supposed to amount to. |

Uncertainties as to whether certain Coal-measure sandstones are
true Pennant, or should be taken as belonging to other geological
horizons.

Contemporaneous denudation having removed certain strata and
seams of coal, possibly not long after they were formed, the seams
being sometimes replaced by beds of sand, etc.

There are many other difficulties in the way of satisfactory
correlation, on which it is not necessary to dwell further, as they
soon present themselves only too plentifully to any investigator of
the subject. It may be briefly stated that the structure of the district,
generally, is so much the reverse of regular, that instances can be
pointed out in which the strata met with at the bottom of a tolerably
deep shaft are the same that had already been passed through at
the top thereof; and in further illustration of the amount of dis-
location the district has suffered, allusion may be made to a locality
where, by simply crossing the breadth of a turnpike road, Old Red
Sandstone may be found on one side, and Coal-measures on the
other; the Lower Limestone Shales, Carboniferous Limestone and
Millstone Grit (present in force near at hand) being entirely absent,
to say nothing of possibly part of the Old Red and part of the
Coal-measures being likewise cut out.

For the purposes of this investigation, and for showing the local
variations, a considerable number of detailed pit-sections have been
drawn, all to the same scale and with similar colours used for
similar descriptions of strata, but in this brief summary it will be
sufficient for explaining a few of the principal points on which
conjectures are hazarded, if we refer to only one or two of the
Somersetshire pits, and to the general typical section of the
Gloucestershire Coal-measures by David Williams, pp. 207 to 212,
vol. i. Memoirs of the Geological Survey, or Sheet 11 of the Survey’s
Vertical Sections; it being suggested that this general section con-
tains, with of course local variations, most, if not all, of the strata
to be found. in the Coal-measures of Somersetshire, and that the
equivalents of the Radstock measures are not, as usually supposed,
missing in it, but to be found in a totally different position to that
in which we have been accustomed to look for them.

If we take the sections of pits which are considered to have been
sunk through both the Radstock and the Farrington measures, as at
Old Grove or Braysdown, we shall find, that if the measures beneath
the red shales, at those places, are correlated, as is usually done, with
the Gloucestershire upper series, there is plenty of room and to
spare on the Gloucestershire section, for the red shales, and for the
whole of the Radstock group above them, but that no such seams
occur in Gloucestershire in the position in which, taking the Old
Grove or Braysdown intervals, we should expect to find them. If,
however, we take the section of the Farmborough sinking as re-
presenting the Somersetshire equivalents of the Gloucestershire upper

348 H. EH. Hippisley—Somersetshire Ooal-measures.

series, including the Gloucestershire measures above the upper series
coals, we find a very striking resemblance, apart from the commer-
cial value of the coals, between the Farmborough and Gloucestershire
sections; so that it appears as if the commonly supposed absence of
the Radstock measures in Gloucestershire can scarcely be explained
by saying that the Gloucestershire measures, as now existing, do not
extend sufficiently in ascending order to include the Radstock mea-
sures, which are usually stated to have once existed in Gloucester-
shire, but to have been removed by denudation.

Similarly, the position of the red shale bed in Gloucestershire,
supposed to be a remnant of the red shales dividing the Radstock
from the Farrington measures, is vastly higher above the Glouces-
tershire upper series seams, than the red shales at Old Grove are
above the so-called Farrington seams at that place.

Again referring to the Gloucestershire general section, it will be
found that red shales occur in no less than four different positions—

Ist. The bed already referred to near the top of the section, about
eighteen feet thick only. 2nd. Below the Gloucestershire ‘Great’
Vein, between it and close to the coal next below it. 3rd. Imme-
diately above, and resting on, the Pennant. 4th. In three beds of
similar thickness to those at Old Grove and Braysdown, about one-
third of the distance between the Pennant and the Millstone Grit.

It is suggested that these last three beds of red shale may be the
Gloucestershire equivalents of the red shales in Somersetshire, which
are taken as dividing the Radstock and Farrington groups at Old
Grove and Braysdown, and that the real Farrington group, that is
to say, the group worked at Farrington Gurney and Old Mills, are,
not the veins proved at Old Grove and Braysdown below the red
shales there, but a group lower still in the lower series, reaching
downwards nearly to the Millstone Grit, instead of to the top of the
Pennant as usually supposed.

At Farrington Gurney Colliery, immediately below the New Red
Sandstone, a bed of red-coloured shale was passed through, in all
probability merely ordinary grey shale coloured red by infiltration
from the red ground next above it, as no such red shales occur at,
or near to, a similar distance above the ‘ Cathead’ Vein at Old Mills,
and the position of this bed of red shale at Farrington Gurney is
quite at variance with the position in which, from Old Grove or
Braysdown data, the Somersetshire red shales should occur.

Cases are known in which this red colouration extends to a con-
siderable depth beneath overlying red ground, the colour being not
merely in the joints and bedding planes, but permeating the entire
substance of the shales.

If the detailed sections at Old Mills and at Ludlows, Radstock
(above the lap), are placed side by side, with the veins called at both
places ‘Middle’ Vein, together, a very remarkable resemblance, in
the details of two sections of which the component parts are arranged
in a peculiarly distinctive manner, may be observed: so much so
that the section at one place might almost be taken as the section at
the other. This resemblance is sufficiently remarkable to afford

H. E. Hippisley—Somersetshire Coal-measures. 349

grounds for suggesting, that the strata at these two places may really
be identical.

This would lead to a further suggestion that the veins at Ludlows
above the lap, as well as the Farrington veins, may possibly be of
the lower series, and that the detached masses of Carboniferous
Limestone at Luckington and Vobster may be, comparatively speak-
ing, in their true places as regards the suggested lower series veins
at Radstock, as far as measures above the slide are concerned. In
short, that the amount of the slide may be far greater than usually
considered, and that these masses of limestone, and the lower series
above them, may either have been brought down by a simple slide
or landslip, from their original position on the Mendips, or that there
is an anticlinal between Norton Hill and New Rock. The former
hypothesis would involve a distance moved, of, roughly, a mile or
more, but instances have occurred, even in the last century, of masses
of ground having travelled nearly four miles during landslips.—
Lyell’s Principles, vol. i. p. 180.

It is not suggested that all the Radstock measures are, as
suggested for those at Ludlows above the slide, equivalent to the
Farrington Gurney or Old Mills measures, but that the remainder are
in reality, as usually supposed and proved, above the red shales, but
beneath the Pennant, and so of the upper portion of the lower series.

It has been remarked that the position of the Pennant gives the
key to the understanding of the whole district, and so it undoubtedly
would if we could be certain that it really was the true Pennant we
had selected as our starting-point; but as it has already been shown
in the Kingswood district, that a Coal-measure sandstone, long con-
sidered to be Millstone Grit, was in reality not so, we are by no
means certain that sandstones, long considered to be true Pennant,
are so in reality, merely on account of the length of time during
which they have been so called.

There are several heavy beds of sandstone which have been sources
of confusion as to the true Pennant (confining the term Pennant to
that of the Geological Survey, and including its extension down-
wards in the Nettlebridge and other districts) ; amongst them is a
bed 66 feet thick as sunk through at Old Mills, the base of it being
63 feet above the “‘Cathead ” Vein there, which bed of sandstone is
suggested as lying between the bottom of the sinkings at Old Grove,
Braysdown and Grayfield and the top of the suggested true Farring-
ton measures; possibly giving rise to the belief that Old Grove, etc.,
were supra-Pennant. This bed of sandstone is also very prominent
at Temple Cloud, being somewhat thicker and several times repeated
by faults there, and has often been described as true Pennant at that
place, apparently principally on the grounds that it has been quarried
for building purposes, as its thickness is easily to be measured.

The other sandstone beds which have done duty for Pennant need
not be discussed in this summary; it is sufficient to remark that,
apart from the evidence afforded by organic remains, it is often
impossible, from lithological character alone, to be certain whether
a specimen is Millstone Grit, Pennant, or one of the other Coal-

300 H. E. Hippisley—Somersetshire Coal-measures.

measure sandstones. Frequently the lithological character is so
entirely distinct, that any one could tell the difference, say, between
a specimen of Millstone Grit and Pennant; but this marked difference
sometimes merges into a marked resemblance, and it may often be
impossible to obtain organic remains to decide the question. It is
always to be remembered that sandstones, even if of no very great
thickness, are apt to claim an undue share of attention as to the
proportion of a district that they occupy, partly owing to their
hardness and the consequent difficulty or expense in working in
them underground, and partly from their prominence (from hardness)
at the surface, rendering the observer apt to neglect the greater bulk
of softer measures which do not show themselves in such an ob-
trusive manner.

Other subjects in connexion with the correlation of the district
are treated of in the original of this summary, the lucidity of which,
it is feared, suffers somewhat by compression and by the absence of
the drawings showing suggested correlation of seams; amongst them—

As to the process by which the commonly accepted theory has
arisen from the extremely complicated structure of a district in
which it is perfectly impossible to trace on the maps boundaries of
series or crops of strata by flowing curved dotted lines, as some-
times attempted.

That some different conclusions would have been arrived at if
sections had always been drawn to a natural, and not to a distorted,
scale, which, however convenient for some purposes, is peculiarly
inapplicable to sections consisting largely of inclined strata.

As to the structure in the two mile interval between New Rock and
Norton Down, and at Strap Pit, Downside.

As to structure at Coal Pit Lane, Bishop’s Sutton and Temple Cloud.

Remarks on some of the faults, with a simple explanation of the
cause of inequality of overlap at the Radstock slide fault.

But sufficient has already been written to show the general
direction in which inquiry into a confessedly difficult subject may
be carried on, and in conclusion the writer begs to thank the
many able men engaged in the district who have kindly afforded
information, rendering it possible to arrive at conclusions, which,
though not put forward by any means as final, or incapable of much
improvement by the evidence of further facts from new workings,
would, but for their aid, have been founded on insufficient data.

Probably the amount of coal within reach in this district is just as
large, whether, though the Coal-measures may be shallower in it
than usually supposed, it contains chiefly only one, the lower, series
of measures so thrown up and down as to be within reach at almost
any point, or whether it consists of three unbroken basins one within
the other ; and it is evident that if at a colliery we have a set of
seams that are found to be of good quality for various purposes, it
makes no difference as to their suitability or value, whether they
belong to an upper or a lower series, though a correct notion of
correlation, if we can arrive at it, is of the highest importance for
new winnings or from a geological point of view.

A. G. Cameron—Peat Deposits at Kildale, etc. ool

TII.—Norres on some Prat Deposits at Kitpate anp Wrst
HARTLEPOOL.’
By Axtan Grant CAMERON,
of the Geological Survey of England and Wales, Member Yorkshire Geological
Society.
EAR Kildale, a small village on the North Yorkshire and
Cleveland Railway, not far from the source of the river Leven,
a railway cutting close to the station shows, in descending order, the
following section.

(a) Peat ius Ac0 as 14 feet.
b) Sandy underclay noc aoc Dirt
c) Pale marly sand

é 16

(a) This deposit is circular in shape, ‘being 14 feet thick in
greatest thickness, thinning away in all directions. It is pale brown
in colour, tough and leathery in structure, and appears to consist
chiefly of decomposed wood, stumps and roots being easily recog-
nized in it. Remains of Deer, Cervus elaphus (Red- deer) and Cervus
tarandus (Reindeer), have been found in the lower part of the peat,
the antlers especially being well preserved.’

(b) Below the peat a sandy underclay usually occurs, of variable
thickness, the average being about 2 feet. A thin band of bog iron-
ore is often at the base of this.

(c) This deposit consists essentially of fine white sand, its yellow
marly appearance being due to the great abundance of Lymnea
peregra, mostly in a broken condition. In some parts, however,
this shell may be found in a capital state of preservation, accom-
panied by minute specimens of Pisidium amnicum ? Helix nemoralis ?
and Acicula fusca, and fine specimens of Helix aspersa.

The sand is sometimes cemented together by the lime in these
shells, and has, then, somewhat the appearance of a calcareous tufa.
At the base of the cutting, water still collects, issuing from the Middle
Glacial Sands, upon which the whole deposit rests.

In this water Lymnea peregra still occurs in hundreds. There
seems little doubt that this deposit is not of any great antiquity,
although we have not been able to ascertain, positively, whether
human beings lived in this district or not before the peat formation,
though it seems more than possible, that this tarn or pond had some
connexion with the moat round the old castle, which formerly stood
close by, but of which not a stone now remains.

A somewhat similar deposit to the above occurs at the Slake,
West Hartlepool, where recent excavations revealed the following
section in descending order.

(a) Soft peat 200 soc ae 8 feet 0 inches,
(b) Blue underclay wee ae Ls soe LO
(c) Boulder-clay ... 206 10 5 0 »

(a) is a soft peat, brown in “colour, containing numerous trees,

1 This paper is published by permission of the Director General of the Geological
Survey.

2 Seamer Carr (once a lake), near Stokesley in Cleveland, when being drained, was
found to be a peat bog, from which numerous skulls and antlers of ‘deer, and the
skeleton of a large ruminant, are said to have been dug out. A stone celt was also
picked up.

302 T. M. Hall—Extent of Geological Areas.

stumps, and leaves matted together. These vegetable remains
are natives of the country. Of 24 stumps measured, the greatest
circumference was 12 feet, the trees being from 18 to 20 feet in
length. Horns of ruminants and the fruit of trees have also been
found.?

(b) Underlying the peat is a thin bed of blue clay in which the
trees probably had root.

(c) Chocolate-coloured Boulder-clay, with pebbles and scratched
stones, many being of the fundamental Magnesian limestone and
contiguous Trias rocks. Boulders of granite, basalt and nodules of
gypsum are also found. Near the base of the clay section is a thin
sand bed 10 inches. The ‘‘boys” left by the workmen to measure
the excavations, in another part of the Slake, showed

Sea sand ace oo 606 doc 2 feet 10 inches.
Shell bed, cockles, mussels 600 On nies ae
Sand ae a avs aes = Aa aiO! eres
Red clay with pebbles.

The Slake appears to have been a hollow eroded out of slightly
inclined Boulder-clay, constituting a fresh-water lake, which merged
gradually into a bog or morass, over which in time the sea broke,
forming a bay which finally silted up. This peat is part of a
so-called sub-marine forest which has long been known to exist
between Hartlepool and Seaton Carew. After a hurricane has
blown off the superficial covering of sand, the peat can be traced
in patches along the shore from Hartlepool as far as the Trias rocks
at Seaton.

TV.—On a Meruop or Estimating THE EXTENT OF GEOLOGICAL
AREAS.
By TownsHEenD M. Hatt, F.G.S.

fe many purposes it is often desirable to form some approximate
estimate of the area occupied by a particular deposit, and in
working out the topography of any county or district (especially for
agricultural purposes), it is frequently necessary to ascertain the
relative extent covered by the various formations. This information,
in every instance which has come under my knowledge, has been
obtained by measuring on the map with a rule, and entering the
results, according to the scale, as so many square miles of surface.
Nothing being more uncommon in nature than a straight line of
boundary, every one who has made the attempt must be aware how
impossible it is to reduce with any degree of accuracy to a geometric
figure such lines as those to be found on most geological maps, and
having recently had occasion to make a calculation of this nature,
for Devonshire, I wish to describe a very simple method which I
adopted with success.
As an ordinary map is supposed to be a counterpart on a certain
reduced scale of the boundaries of the district it represents, so a
geological map would be presumed to show the exact limits of each

1 Young and Bird, in their “ Geological Survey,” mention having found in this
peat at Hartlepool, the remains of insects, particularly the elytra of beetles.

T. M. Hall—Extent of Geological Areas. 353

formation. Proceeding on this reasoning, it occurred to me that,
instead of the very troublesome and uncertain method of bringing the
areas into figures and measuring their superficial extent, it might be
quite possible to arrive at equally good, if not better results by means
of scales and weights—in other words, by cutting out in the paper
the areas according to their outline, and then weighing them sepa-
rately, the products being taken either as parts of the whole, or
compared with one another. To insure success, in addition to
accurate weights, an absolute uniformity in the quality and weight
of the paper is a sine gud non, and the separate sheets on which the
Ordnance Maps are printed would not always fulfil this latter re-
quirement. J was consequently led to adopt a safer and less ex-
pensive method than that of cutting up the maps themselves. The
area of Devonshire being so large, measuring on the scale of one inch
to the mile, six feet in height, by five feet eight inches in width, I
could not procure any single sheet of paper of these dimensions:
however, two or three copies of the “Times” afforded an excellent
substitute, and as it is manufactured by rolls of some miles in length,
it may be supposed that it would be uniform both in quality and
weight. To prove this, I first laid the sheets over the Ordnance
Maps, and cut out very carefully the boundaries of the whole county.
Then taking the square mileage of Devonshire from the official
returns, I measured off with a rule as large a piece of paper as
would represent the square root of this known quantity. The weight
of the two sheets when put into the scale exactly coincided, viz.
107°5 grammes. Being satisfied thus far, I proceeded to cut out in
the paper all the formations according to the boundaries laid down
by the Geological Survey. These portions were weighed separately,
placing all the strips representing alluvium together, then all the
greensand, and so on down to the Carboniferous and Devonian. The
results were then calculated as proportional parts; the whole area
of the county being taken as 100, and by this means I obtained the
following figures :—
Metamorphic Rocks (Start Point and Bolt Head) oo | WOE

Devonian series Pah oul
Carboniferous se aes Boe BaS na Pee 4193
Granite ae ak Site ws wate aes ese 9°88
Triassic series eee one as See oa soo ee
Lias ues oe ae as on Hye ie 0°37
Cretaceous ss ive ane abe Roe es 4-47
Miocene... te: ae a0 eS See Bae 4°46
Alluvium ... de aes ze Sse see a 2-00

100:00

I should add for the information of those who may wish to try the
experiment, that as newspaper is too thick to admit of tracing the
boundary lines through it, I laid a large plate of glass on the map,
and with a pen traced the lines on its surface. Before the ink had
time to dry, the paper was spread on the glass, when the lines were
transferred to it, as in a lithograph.

DECADE II.—VyOL, V.—NO. VIII. 23

354 Notices of Memoirs—E. Favre—Zone of A. acanthicus.

IN| @ Fee er SS) @ ea a eae Neale o

——_—_.

J.—On tue Zone or AvMoniTES ACANTHICUS OR AMMONITES
TEN UILOBATUS.

N an elaborate memoir descriptive of the fossils and localities of
the zone of Am. acanthicus in the Swiss and Savoy Alps, M. E.
Favre, after a careful comparison of the fossils with those from other
Jurassic strata, together with remarks on the nature and age of the
fauna of this zone, gives the following résumé of his researches.

1. There is no general break in the Upper Jurassic strata in
the Alpine or Mediterranean regions. —

2. The zone of Am. acanthicus of the Alps of Switzerland and of
Savoy is the equivalent, in the Hastern Alps, of the zone of Am.
tenwlobatus, and Am. isotypus and of the zone of A. Beckeri.

3. Itis the equivalent, in the Jura, of the zone with Am. tenuilobatus,
and of the zone with Am. Hudoxus and Am. pseudomutabilis.

4. The zone of Am. tenuilobatus is the exact equivalent of the
Astarte zone (terrain astartien), of which it is only a peculiar facies.

o. The stratigraphical position of the zone Am. acanthicus and its
paleeontological affinities unite it closely with the Kimmeridgian.

6. In all the Alpine region, there is a very marked paleontological
line between the zone of Am. acanthicus and the strata upon which
it reposes, which are, either the zone of Am. transversarius or of Am.
bimammatus. The latter has more affinity with the subjacent strata
and ought to be classed in the Oxfordian. There is, on the con-
trary, a close paleontological relation between the zone with Am.
acanthicus and the Tithonian strata which overlie it.

7. The general classification which would best suit the whole of
the Alpine strata would be to fix the upper limit of the Oxfordian at
the base of the zone with Am. acanthicus, and to give the name of
Kimmeridgian (or Alpine Kimmeridgian) to the whole of the beds
comprised between the Oxfordian and the strata of Berrias or the
base of the Neocomian. ‘This name should be employed here in
the sense which M. Waagen gave to it in 1865; and which M. Loriol
also attributes to it; except a slightly less extension of the lower
part, the last author makes it to include all the strata to the zone of
Am. transversarius. However, this latter difference is not very im-
portant in this region, since the Corallian facies inferior to the zone
of Am. acanthicus is not here developed... The zone with Am.
acanthicus would be the Lower Kimmeridgian, and the Tithonian
beds the Upper Kimmeridgian. The equivalents of the Jurassic
and Alpine facies are approximately given in the accompanying
Table:

1H. Favre, La Zone a Ammon. acanthicus dans les Alpes de la Suisse et de la
Savoie.—P. De Loriol, Monographie paléontologique de la Zone a Am. tenuilobatus
de Baden.—Mémoires de la Societé Paléontologique Suisse, Basel, 1877, vols. 3, 4.

000

Notices of Memoirs—E. Favre—Zone of A. acanthicus.

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006 Reviews—Southal?s Epoch of the Mammoth.

IJ.—Lanp Puants 1n THE Sinurtan Rocks.

Count Saporta, in his report to the Academy of Sciences on the
Fern (Hopteris Andegaversis), obtained from the Silurian slates of
Angers, remarks that this important discovery was forestalled in
America, where remains of Silurian land plants had been found.
The first of these, found some years ago by Dr. 8. 8. Scoville, in
shale of the Cincinnati group, and provisionally referred to Sigillaria, —
were briefly described in the American Journal of Science for 1874
(p. 31). Dr. Newberry also noticed them in the same Journal
(p. 110), and considered they were casts of some large Fucoids or
marine plants. These remains have been again studied by Prof.
Leo Lesquereux, together with other specimens sent to him from
the Silurian of Cincinnati and also from the Lower Helderberg sand-
stone of Michigan, which, from their characters, seem to him to
be evidently representatives of land vegetation, and the description
of them was communicated to the American Philosophical Society
(Oct. 19th, 1877).! The following are the species noticed ; Psilophy-
tum gracillinum, P. cornutum, Annularia Romingeri, Sphenophyllum
primevum, Protostigma sigillaroides.

Prof. Lesquereux remarks that the character of these Silurian
plants, described by him, give us a microcosmical representation of
the flora of the Carboniferous, so simple and at the same time so
admirable in the multiple division of its specific forms ; and thus we
now have represented in the Silurian—

Ist. The Lycopodiacee, by species of Psilophyton, diminutive forms
but primitive types of the Lepidodendron.

2nd. The Ferns, by a species related to Paleopteris or to the group
of the Neuwropteride, which is the most common species of the coal.

3rd. The Calamitee, by Sphenophyllum and Annularia, these
forming two sections related to the Equisetacee. .

Ath. The Sigillarig, placed by some authors as an order of plants
between the Conifers and the Cycadez, and here represented by the
Protostigma.

doth. The Fucoids, represented by Calamophycus septus.
J. M.

REVIEWS.

J.—Tuer Eprocn oF THE MammorH AND THE APPARITION oF MAN UPON
THE Eartu. By James C. Sovurnanz, A.M., LL.D., Author of
the “ Recent Onrern or Man.” Crown 8vo. pp. 430. (London:
Triibner & Co., 1878.)

E give the size of this book lest it should be confounded with

W the royal 8vo. issued by the same writer on the same topic so
ently as 1875. This rapid re-composition reminds us of the

method of the late Sir Charles Lyell; but although Dr. Southall

writes easily, he does not yet possess either the caution in collecting
and weighing evidence, or the charming philosophic style which

1 Proc. Amer. Phil, Soc. 1877, vol. xvii. p. 163, pl. iv.

Reviews—Southall’s Epoch of the Mammoth. BOT

distinguished our great literary geologist. The new book is how-
ever a great improvement on the old. Many lengthy disquisitions
are wisely left stored up in the latter, whilst many new facts are
referred tu, so that the present compact volume is not only cogent
in advocacy, but contains much information on the subject on
which it treats. When we have observed that there is a lack of
original research (to which it does not, however, pretend), we have
mentioned the weak point in the work as a contribution to deduc-
tive science. The tendency of the work is strongly in favour of a
geological chronology substantially in harmony with inferences
drawn from the writings of Moses.

Ethnology is referred to, in order to found an argument-that the
unity of the race requires that the flint-tool men could not have been
precursors of the civilized Egyptians. As we do not know that they
were contemporaries, they are concluded to have been offshoots and
successors; and therefore, as Egyptian civilization is not more than
ten thousand years old, so neither can the gravel-drift men be.

The lake-dwellings are removed from the question by proofs of
their use within the historical period. “Of course some of them
may be 4000 years old; but there is no evidence to prove that the
oldest is older than 3000 years.” The same is the case with the
- refuse-mounds, in both hemispheres. The “three ages” are, in
Dr. Southall’s hands, contracted in dimensions by the proofs that
stone and bronze, stone and iron, and all three, have been in use
together. The last in Chaldean tombs; bronze, iron, and some-
times flint, in Assyria; stone, in Egypt down to the eighteenth dy-
nasty ; stone and bronze in the Troad down to the seventh century
B.c.; that there has been no stone age in Africa,’ that iron was
unknown to at least one great tribe of Scythians at the beginning of
our era; that, in America, stone and bronze are found together ;
that the metals do not appear in Western and Northern Kurope until
just before a.D., and stone continued afterwards in use also; and,
lastly, that in a considerable part of Europe there mever was a
bronze period at all. He concludes, so far as this branch of evidence
is concerned, that there was no gap between the Paleolithic and
Neolithic ages, therefore no immensely long period is required.
“Behind the Pyramids in Egypt, and the cities of Erech and
Calneh in Southern Babylonia, there is nothing, and nothing to
indicate the earlier presence of the human race. There was no
Paleozoic age, in fact, no stone age, in those countries.” In brief,
the argument is,—the first populations of Europe came from Asia ;
the first people in Asia, those of Chaldza and Mesopotamia, like the
people of Egypt, appear on the scene in a civilized condition from
6000 to 10,000 years ago: the first Huropeans can be no older than
this. The author quotes the opinions offered at the Stockholm
Conference that the first iron age shown in Scandinavia is in the
fourth century ; and therefore where, as in Scandinavia, this was
preceded by a stone age, the latter need not be assigned to any

! This seems to be a singular oversight, as stone implements are abundant in Cape
Colony and elsewhere, and have been fully noticed.—Eprr. Gzou. Mac.

308 Reviews—Southall’s Epoch of the Mammoth.

great antiquity. Say, with Worsaae, about 3000 years as the age
of the Trojan war, at the utmost 2000 years B.o., which is about the
date of the closing effects of the Glacial Period. In order to dispose
of the prima facie evidence for great antiquity yielded by the bone-
caves, with their undoubted association of man and mammoth, under
several successive floors of stalagmite, Dr. Southall undertakes to
show from the researches of the zoologists, that the mammoth
lived in the South of France, with the reindeer, in comparatively
recent times, and therefore he concludes that this was so in England,
and that the rate of deposit of stalagmite, and the rapid change of
levels, and alteration in physical geography, all occurred within a
few thousand years. The evidence as to this is pretty fully referred to,
and though the author breaks a lance with Prof. Boyd Dawkins, he
nevertheless accepts many of the facts and frequently the opinions of
such experts.

The argument of the present work is that the caves of Neolithic
age contain bones of the reindeer and cave-bear; these were, es-
pecially in Southern Europe, the contemporaries of the mammoth and
rhinoceros ; the latter cannot therefore be far removed from the Neo-
lithic date. The assumed recent imbedding of the great mammal
carcases in Siberia and Ohio is adduced as rendering it “not only pro-
bable, but almost certain, that the mammoth, the mastodon, the mega-
therium, and the tichorhine rhinoceros, were living at a recent date.”

““We have thus fulfilled our promise, and proved the recent
existence of the so-called Paleolithic fauna. The cave-horse, the
cave-bear, the cave-lion, the cave-hyzena, are still living; the cave-
lion is mentioned historically in Europe a few centuries before our
era; wild horses scoured the plains of Russia a few centuries ago ;
the urus survived to the sixteenth century; the aurochs still survives;
the reindeer is traced down to the beginning of our era, and even to
the twelfth century; the great elk survived equally as late; the
mastodon and the mammoth, and the woolly rhinoceros, are found
under circumstances that imply their existence a few thousand years
ago.”

Proceeding from this to the consideration of the drift-implements
(the real difficulty in the whole case), Dr. Southall argues that the
peat of the Somme rests immediately on the implement gravels,
and that in the caves, especially those of Belgium, the Neolithic also
rests immediately on the Paleolithic, so that there is proof of
suddenness and absence of interval between the two, in fact, no gap.
He offers the following explanation of the gravels : —

“But how then shall we explain the occurrence of the implement-
bearing gravels, eighty feet or more above the present level of the
river? Our opinion is, that when those gravels were deposited, the
valley was filled by water from bluff to bluff—a body of water one
or two miles at least in breadth, and 100 or 150 feet deep. It was
the Palgolithic Flood, an event now well recognized by geologists.
It is a secondary question whether this flood was occasioned by an
inflow of the sea, or by the Pluvial Period of Mr. Tylor. That there
was such a flood, covering no inconsiderable area in Belgium, in

Reviews—Southall’s Epoch of the Mammoth. - 359

France, in England, in the valley of the Tiber, in the valley of the
Mississippi, and elsewhere, there is no doubt—what Dr. Andrews
designates as the Flood of the Loess.”

The sponsors for this flood are Messrs. D’Orbigny, Alfred Tylor,
Prof. Andrews, and Prof. Prestwich. Perhaps, in analogy to another
kind of sponsorship, these gentlemen hardly know what it is that
they undertake! If we enlarge our view and take in the intervening
plains on which implements have been found in scattered gravels and
caves on hill-sides once at the water-level, we have phenomena which
cannot be accounted for by any single flood, or by any flood alone,
but require several floods, with intervening periods of repose, the
whole constituting a great mammalian epoch, during some part of
which man occupied and dwelt; after this there was more flood,
accompanied with considerable elevation and movement of the
surface. The problem is, how long did this post man-and-mammoth
period last? Could it all have taken place within a limited period,
after the first appearance, and disappearance, and before the re-
appearance of man? Can the geological phenomena between
the disappearance and reappearance of man be fairly explained on
the supposition of their occurrence within the lapse of, say, a
thousand years? To these questions Dr. Southall’s book brings no
direct reply.

The gravels are still mysterious. The time and the force required
to rake off a surface of chalk, to roll its flints into pebbles, to
grind pebbles into sand, to wash another part of the contents into
coloured clays and fine sands, to expose beds of these to the winds
so as to create dunes, to have alternate land and water, alternate
still and violent waters, occasional inroads of the sea in places
now far beyond its reach, to have successive rises and depressions
of land, to have big mammals living, dying, and entombed, to
have surfaces of vegetation growing and again buried under
aerial or watery accumulations, to have man sufficiently settled
to cultivate at least some imitative arts, then a displacement and
a deluge, and then the slower reduction of rivers to present
channels,—these are a few of the difficulties which beset the travel-
ler in his journey amidst Paleolithic deposits. The gravels them-
selves furnish us with such an inconstant series, that many able
men who have given years of study to them are not yet agreed
on their chronology. Geological knowledge respecting their dura-
tion cannot at present be said to be conclusive either way ; and in
regard to geological time the ‘might have been” is not yet super-
seded by the authoritative “must.” The advocates for both sides
are still entitled to hold and express their opinions, and if the
tendency of recent discovery and discussion has, as a fact, been
towards the adoption of the proposition put forward during the
infancy of the inquiry, that the mammalian epoch reached far nearer
down to our own day than was supposed; yet who shall estimate
the duration of that period antecedent to human chronicles or even
traditions ?—to attempt to measure it by our feeble data, is like
taking soundings in. the ocean with a “ two-foot rule” !

860 . Reviews—Miller’s and Shertchly’s Fenlands.

A singular illustration is afforded, in the Somme Valley itself, of
the comparatively recent occurrence of phenomena similar in appear-
ance to those of prehistoric times. M. de Mercey has described a
deposit superimposed on the (Celtic) peat, comprising, first, brick-
earth with fragments of Roman pottery and land-shells, having at
its base a few pebbles and marine shells, and, lying over it, a bed
of river-gravel. If authentic, the events and changes thus indicated
must have all occurred since the days of Julius Cesar. On the
other hand we have Mr. Belt, in the current Quarterly Journal of
Science, treating the valley-gravels as pre-glacial.

Dr. Southall relies on the conclusions of Professor Andrews re-
specting the positive age of the remarkable terraces: in the river
valleys of North America, and on Professor Whichell’s calculation
on the Falls of St. Anthony, recently brought before the Geological
Society of London. The author’s conclusion seems to be that the
present surface phenomena are principally of glacial and sub-glacial
age, in the Northern hemisphere, and cannot be carried back fur-
ther than about 7000 years, and that land-ice, with all its incidents,
lingered in Northern Europe long after the cessation of the Glacial
Period proper.

Dr. Southall’s volume is not without the liveliness which the
advocacy of a particular hypothesis gives; indeed the spirit of
the Advocate is oft-times far too prominent ; evidence being admitted
and conclusions based thereon, without sufficient regard for the
reliability of the witnesses cited. It hardly accords with the
caution expressed in the preface :—‘“It is a question which should
be decided apart from all theological prepossessions, and in no
way prejudiced by any supposed interpretations of a biblical reve-
lation on the subject. It is purely as a question of science that I
propose to discuss it; and if we arrive at a conclusion out of
harmony with religion let it be squarely recognized, and let the
adjustment constitute a separate task.” leek

I1.—Tue Fentanp—Past anp Present. By Samurn H. Mrisr,
F.R.A.S., etc., and Sypney B. J. Sxertcuty, F.G.8. Royal
8vo. pp. 649, with a map, and 27 plates. (1878: Wisbech,
Leach & Son ; London, Longmans, & Co.)

N the Geonocican Magazine for May last, we called attention to
a Geological Survey Memoir on “The Geology of the Fenland,”

by Mr. Skertchly. We have now much pleasure in announcing the
publication of the handsome and beautifully illustrated work whose
title is given above. This work, which contains nearly twice the
amount of material, printed on superior paper, and in far better type,
than the Survey Memoir, with excellent illustrations, is issued to sub-
scribers at less than half the cost of the Government publication,
and even its published price of 31s. 6d. contrasts very favourably
with the enormous (almost prohibitive) charges now put upon the

Survey works by H. M. Stationery Office.

This new work on the Fenland is an exhaustive treatise on the

Archeology and Natural History of the district. In the Geological

Reviews—Barrande’s Cephalopoda of Bohemia. 361

chapters Mr. Skertchly supplements the detailed accounts which he
gave in his official work, with an amplification of the general results,
which are written so as to interest the ordinary reader as well as to
furnish food for the geologist. We must content ourselves with
briefly indicating some of the many subjects treated here, which are
of special interest to our readers, such are the history of the present
indigenous fauna, and of that of pre-historic times, the migration and
diffusion of species, the causes of changes of Climate. The growth
of Peat, the question of Water-Supply, and the subject of Climate and
Disease will suggest many topics of interest. Among the subjects
more likely to raise discussion are those connected with the formation
of the Chalky Boulder-clay, the alternation of Glacial and Interglacial
beds, the Palzolithic gravels, and the age of the Brandon Beds.
The entire subject is however rich with interest, and the authors
have evidently spared no pains and no expense to render their work
as complete in every respect as possible.

TII.—Cérnatopopes. Erupes GENfRALES; EXTRAITS DU SYSTEME
SrzurreEN pu Centre DE LA Boutue. Par Joachim BaRRANDE.
8vo. pp. 253, 4 plates. (Prague and Paris, 1877.)

aes. has completed his. magnificent work on Paleozoic

Cephalopods. Commenced in 1865 with the publication of the
first series of his plates, and continued at irregular intervals but
without interruption up to nearly the close of last year, this splendid
contribution to science extends to 544 large 4to. beautifully executed
plates, and to about 3600 pages 4to. of letterpress.

In the smaller publication we now refer to more especially,
Barrande has given us short extracts from the concluding chapters
of his work, or those including his ‘‘ General Considerations of the
Cephalopods,” and has produced, as it were, a brief summary of the
ably reasoned arguments given more in detail in the larger. work,
so that an excellent general idea may be quickly obtained of the
more important conclusions at which he has arrived. From the
character of the publication, it will be obvious that it would be
impossible to condense into a few lines, for which alone we can
find space here, what is already a highly condensed summary of
detailed and close reasonings. In his chapter xvii. the reader will
find a most interesting résumé of all previous researches on the
initial form of the Nautilide, the Goniatide and the Ammonitide, in
which the position, form, size, origin and object of the cicatrix on
the initial cowl of the shells, are fully considered, and the remark-
able contrasts offered in these respects in the different groups. He
then winds up this chapter with some considerations on the chron-
ology of the groups, and finally a brief statement of all his con-
clusions on the initial forms of the Cephalopods. As to the vertical
and horizontal distribution of the Cephalopoda in Silurian countries,
it seems established, that this order has appeared suddenly, and for
the first time, at the commencement of the second fauna. At that
time the only Cephalopods belonged solely to types of the one

362 Reviews—Barrande’s Cephalopoda of Bohemua.

family of the Nautilide, very varied in form, from Orthoceras to
Nautilus and Trochoceras, as proved by the second faunz of the
N. American and N. European areas. In Bohemia, the second
fauna only offers straight forms of the family, and the “colonies”
even have only given two curved forms of the genus Cyrtoceras.

The great development of the Nautilide in Bohemia occurs in
Barrande’s étage EH, in which more than 687 specific forms of the
family occur (or including the supplementary lists of Barrande’s
Série tardive, no less than 856 species). No species occur in the
beds above belonging to the zones f1, f2, 91,92, but after this
long interval Nautilus reappears in zone g 3, with three new species
different from those of zone E. Meanwhile the genus Goniatites is
absolutely unknown in the second fauna of all Silurian countries in
either continent which have been examined up to date! The
earliest appearance of Goniatites in Bohemia was during the
deposition of Barrande’s zone f2, in which he shows the existence
of seven species of that type.

Now it is interesting to notice that this epoch of the first appear-
ance of Goniatites corresponds to the cessation, which has been just
noticed, in the existence of Nautilus in Bohemia. But, Barrande
remarks, this fact does not tend to prove the filiation of the new
type to the more ancient, because, in reality, where the new form, the
first Goniatites, appeared suddenly in the Bohemian basin, there
was not a single Nautilus to give birth to them. Further, at its
first appearance in zone f 2, the genus Goniatites furnishes 7 distinct
species, while the genus Nautilus only furnished 5 during its
temporary existence in Bohemia in zone e 2: numbers which are
far from corresponding with the slow and successive steps in trans-
formation, admitted by theory. In fact, all the appearances and
disappearances have taken place suddenly.

Some time after its first appearance, Goniatites seems to disappear
during the deposition of the very thick zone g 1, at the top of which
we again find it. It then continues with variations in the number
of its specific representatives through the zones g 2, g 3, h 1, attaining
its maximum number (14) in g 3. Now itis precisely during the
deposition of this same zone that we find Nautilus reappearing with
three species. It is difficult to imagine how it reproduces itself after
so long a cessation, precisely at the time of the maximum im-
portance of the Goniatites, which theory would indicate as replacing
the Nautili. .

Barrande here gives an amusing (p. 75) imaginary discourse of
an evolutionist lecturer on the derivation of the Goniatite from the
Nautilus, “which it replaces at its disappearance from the seas of
Bohemia without our exactly knowing why,” ‘‘ mais sans doute par
Veffet de la selection naturelle”—and discusses the total discord-
ance which is here proven between theory and fact, with reference

1 The question of the asserted occurrence of two forms of Bactrites, one in
Bohemia, one in Russia, in the second fauna, will be found fully discussed in yol. in,
of Texte, p. 804,

Reviews—Barrande’s Cephalopoda of Bohenua. 363

to the initial portion of the shell of the Cephalopods in the three
families of the Nautilide, Goniatide, and Ammonitide. And closes
this portion of his paper by proposing a few questions, which, in his
opinion, must be answered before we can establish any idea of filia-
tion, or derivation, between the Nautilide, Goniatide, and Ammoni-
tide. These are—if true that the Goniatites and Ammonites are
_ derived from the Nawutili, why is their siphon invariably on the
convex side ? why is it never inflated, or nummuloid as in the
Nautilide? why, under these two points of view, is there never
any trace of atavism, amongst the Goniatide and Ammonitide ?

The second part of the work under review is devoted to the
discussion of the vertical distribution of the Cephalopods in Palzo-
zoic countries. It will be found to give a wonderfully detailed and
careful summary of all the known facts, as to the occurrence in
successive formations of the various genera and species. The
horizontal distribution, or occurrence in local groups, is also fully
discussed. And the special distribution in Bohemia given in much
detail—into which we cannot follow the author. In this portion of
his work, also, no possible opportunity is omitted to indicate the
apparent contradiction between facts and any theory of evolution.

The third part gives a general résumé of the author’s studies on
the Cephalopods, taken under the separate heads: 1. Investigation
of any traces of evolution of the Cephalopods, in the first appear-
ance and successive re-appearance of generic types, and in specific
forms. 2. Similar investigation as to each of the elements of the
shell in the Palasozoic Cephalopods. 38. Remarkable peculiarities—
(a) in structure of shell; (6) unexplained connexion, between dif-
ferent elements of the shell; (e) forerunners of types—avant-
coureurs—the species ‘ prophétiques’ of Agassiz; (jf) connexion
between the existence of large siphons and the brief duration of
certain types, and the geographical distribution of their species;
(g) the anachronism exhibited by the forms intermediate between
generic types. And then, 4. Final conclusions.

With some additional notes, among which will be found quoted,
with much satisfaction, the labours and conclusions of Mr. T. David-
son on the Brachiopoda; of M. Grand’Eury and Mr. W. Carruthers
on evolution in the Vegetable Kingdom, as represented by fossil
plants, M. Barrande concludes this very important and remarkable
brochure. We shall just give in a few words his final conclusions.
It will be obvious from the headings we have given, that it would
be impracticable to give the necessary space for any full discussion
of his results.

He says (p. 230) : On the whole, we have not discovered any trace
of the supposed evolution, either in the first appearance or in the
vertical reappearance of the generic types of the Cephalopods; or in
the appearance and succession of their specific forms; or in the
appearance of the elements of the shell. On the contrary, we see at
all ages, the genera, the groups and the species, without any genetic
connexion, rise and disappear with a suddenness and without inter-
mediate forms, which are inexplicable; while we have also proved

364 Reviews—Barrande’s Cephalopoda of Bohemia.

a remarkable stability in the generic characters, in the specific
distinctions and in the elements which form the shell of molluscs of
this order. ‘The theory of evolution of the Cephalapods, like that
of the Trilobites, appears to us to be a mere product of the imagination
without any foundation in fact.”

We have given M. Barrande’s conclusions with all their force,
though necessarily without the detail of argument which he has
brought to their support. We cannot follow him in this detail, but
we must suggest great caution in admitting as ‘proven’ all that is
assumed as such in this brochure. For instance, in his general
conclusions, he starts by recalling two predominant facts, so pre-
dominant in truth as to rule everything else. Now the first of these
is the absence of Cephalopods in the primordial Silurian fauna. It
may be, and we admit that M. Barrande has fully and fairly quoted
the evidence, that no Cephalopod has as yet been recognized in this
fauna. But he would be indeed a bold man who, therefore, would
assert that no Cephalopod existed. Is there not in this, as in so
much so-called Geological reasoning, a little suspicion of what a
logician would call “arguing in a circle”? Has the “primordial”
age of the several groups been determined on evidence altogether
independent of such considerations of fossil data? Has not the
belief in this supposed absence of Cephalopods from the earlier
stages been sufficient to determine at once, that any beds in which
they were found could not be of that epoch? Has there always
been sufficient care, and sufficient detail given to analysis of the
accompanying facts? In any case, the attempt to base such import-
ant and widely influential conclusions on what is confessedly purely
negative evidence (if there can be such), is fraught with danger,
and is to be most jealously guarded. And a reference to M. Barrande’s
details shows in how very many particulars he has no other evidence
to rely upon.

We rejoice to think that he has been enabled to complete this
magnificent contribution to Paleontology, and we trust sincerely he
may yet be spared to carry out the intentions which he announces
as now in progress—the rapid issue of more than 120 plates of the
Paleozoic Gasteropoda, and of 114 plates of Brachiopoda (all ready
printed), besides a very large series of the Acephala. In common
with every paleontologist, we look with anxious longing for these
valuable contributions to the literature of our science ; and whether
the progress of his investigation may lead to the confirmation of his
present views as to the illusionary nature of any theories of evolution,
or may tend to modify these, we know that we shall have from
M. Barrande what is beyond all theory in value,—the carefully
worked out, and carefully thought out expression of his honest
opinions. We most heartily congratulate him on the completion of
the Cephalopods, and wish him every success in the further prose-
cution of his labours. T. OpHam.

Reviews—Hayden’s Atlas of Colorado. 365

IV.—GeEoLoGicaAL AND GEOGRAPHICAL ATLAS OF COLORADO, AND
Portion or Apsacent Territories. By F. V. Haypen, U.S.
GeoLocist-In-CHarcEe. Published by the Department of the
Interior, under the United States Geological and Geographical
Survey of the Territories, 1877.

E have just received, through the agency of the Smithsonian
Institution, this grand contribution to the Geology of America.

Most of our readers are aware that a general survey of the very large

and important, though often very inaccessible areas, known as “The

Territories,’ was organized in the year 1867, and those who are

observers of American progress have watched with increasing in-

terest the vast advances which have been made in this Survey under

Dr. F. V. Hayden. Very few weeks have elapsed since we received

Vol. VII: of the Memoirs of the Survey, being a large quarto vol. of

370 pages and 65 plates, on the Tertiary Plants of the West, of

which another similar volume (VI.) formed the Cretaceous Flora.—

1877 saw the appearance of a very large volume on North American

Rodentia (for the researches of this all-embracing Survey are directed

to many subjects besides Geology), while a year or two before we

had a volume on the Cretaceous Vertebrata by Cope, illustrated with

57 beautifully executed plates. The Bulletin (of shorter papers) has

already reached the middle of Vol. IV.—In 18738, the work of

the Survey was systematically commenced in Colorado. And here
we have the results of four years’ labour (1873-74-75-76) produced

and published in a finished state in the year 1877!

And such four years of labour as these must have been! an area
exceeding that of Ireland, in parts most inaccessible, everywhere diffi-
cult to travel in, open to disturbances, or fears of disturbance, from
unsettled Indian tribes, where everything had to be carried with
the observer, and he thrown entirely on his own resources, and
such limited aid as he could bring with him; such an area has been
triangulated, measured, physically examined, and mapped; its drain-
age carefully determined, its economic and agricultural divisions
noted, and its geological structure carefully investigated.

We have no hesitation in saying that Prof. Hayden may justly
point to this as a success, rarely ever approached, probably never
equalled. And may justly recount with pride the names of those
few who have so ably and so untiringly carried out his wishes.

The Atlas consists of twenty sheets of large double elephant size.
These are in two series: first, of 4 sheets, which are general, and em-
brace the entire area on a scale of 12 miles to one inch. These show
(1) The Triangulations, (2) The Drainage, (8) Economic Map, (4)
General Geological Map. The second series consists of 12 sheets,
in pairs, six representing (plain) only the topographical features of
different parts: N.W., N., Central, W., S.W., and S. Central Colo-
rado. And six sheets exactly corresponding, on which the geologi-
cal lines and colours are given; then there are two sheets of
geological sections, and two of panoramic views. The detailed
maps are all on the scale of four miles to the inch, and embrace each
2% degrees of longitude, and 1} degree of latitude—thus covering

366 Reviews—Hayden’s Atlas of Colorado.

the entire area of Colorado, and some adjacent parts of Utah, Arizona,
and New Mexico. These maps are also contoured, the contour lines
representing, approximately, intervals of 200 feet vertical.

All these maps are very beautifully drawn and beautifully printed,
and are types of careful, clear, and excellent work. The colouring
is also admirably printed, with a wonderful transparency and even-
ness, and with really admirable “register.” Altogether the execu-
tion of the sheets of this noble atlas leave nothing to be desired.

We cannot pass on without noticing the two sheets of panoramic
views. We have had in this Macazinz opportunity before now of
drawing attention to the really effective aid which such views give
to the student in a ready and clear understanding of the descriptions
of a country.1 And we think the simplest inspection of the few
given in this atlas will be quite sufficient to prove to any one the
immense value of such outlines in enabling those who have not seen
the districts, to realize the facts. Who can compare the curiously
broken and rugged outline of the quartzite group of the San Juan
Mountains as seen from the Rio Grande Pyramid (Sheet xx.) with the
peculiar serrated and jagged peaks of the trachytic mass of the La
Plata Mountains, looking east from Mount Hesperus, on the same
sheet, without carrying away with him a vivid conception of the two.
areas, and without, at the same time, we may remark, being struck
with the vast difficulties the surveyors have had to contend with in
such work? True: the ground is well visible, there is no dense
jungle and no thick undergrowth of impassable and deadly vegeta-
tion to interfere with his progress. But the very loneliness—the
conviction of desolation, would in itself numb the energies of many; _
and double honour is due to those whose unflagging interest in their
researches, and whose untiring devotion to their work, have enabled
them to complete this great task.

Tt is too late now to devote any space to a more detailed examina-
tion of the geological information given on these maps. We shall
probably have other opportunities of returning to the subject. But
we could not avoid at once congratulating Prof. Hayden on the com-
pletion of this grand atlas, and on the success which has thus
crowned the labours of his very efficient and zealous staff. If any
sense of shame yet remain in some other Survey staffs, we cannot
help hoping that they may be excited, by the comparison, to a little
more earnest and single-minded devotion to their labours than has
of late years distinguished them.

There is still an immense area before Prof. Hayden. And we
shall look with eagerness for successive atlases of the other “'Ter-
ritories”’ also.

It would be injustice to our American brethren to omit noticing,
with the highest approbation, the marked liberality with which the
costly and valuable labours of these State Surveys are distributed to
all who are likely to take a real interest in the subject, or can in any
way reciprocate by exchange of similar publications. There is not a
library of any value for the student of Natural Science in this country

1 See Gzou. Maa. Decade II. Vol. V. April, 1878, p. 174, ete.

Geological Society of London. 367

which is not enriched by a series of these American Survey Publica-
tions —while he might search through half the counties in the king-
dom before he could obtain access to a copy of the publications of
the Geological Survey of Great Britain. In early years, a wise and
well-judged arrangement was made by which such publications were
issued at an uniform rate, which was reasonable, and which brought
them within reach of most persons interested. But lately a new
system, so far as we can learn without any public sanction, has been
introduced, and all expenses whatever incurred in the printing, etc.,
of a Report are put to the charge of that Report, and as only small
editions are printed, they naturally enhance the cost of each pamph-
let or volume. But in addition to this, not only is this charged at a
fixed rate per sheet or page, but the cost of every alteration is added,
and the public is made to pay for the incompetence or carelessness of
the editor, who, not knowing exactly what it is he wants, has the same
passages printed over again two or three times. Thus it happens,
that reports are saleable only at a price which perfectly forbids their
purchase. While the works are produced on paper more like what
is used for the columns of a halfpenny newspaper, than what would
be expected in valuable and costly scientific reports. And the illus-
trations are either of the poorest and worst executed kind, or are
so destroyed by bad printing on bad paper that they are simply
disgraceful. We are well aware that this is not caused by the
Officers of the Survey itself, and that, in fact, they suffer severely
by it and regret the result as much as the public at large, but the
facts are as stated.

Nothing of this kind will be found in this Atlas of Colorado, the
paper is excellent, the printing is excellent, the execution is excel-
lent. T. OLDHAM.

REPORTS AND PROCHHDINGS.
sig gee

I.—GrontogicaL Sociery or Lonpon.—June 5, 1878.—John
Evans, Hsq., D.C.L., F.R.S.,, Vice-President, in the Chair.—The
following communications were read :—

1. “On the Quartzites of Shropshire.’ By Charles Callaway,
Esq., M.A., B.Sc., F.G.S.

In a former paper (Q.J.G.S. xxxiii. p. 652) the author indicated
that part of the so-called quartzites of the Wrekin are “ Hollybush
Sandstone” ; in the present communication he shows that the whole,
both in the Wrekin and Church Stretton areas, are of Cambrian or
Precambrian and not of Caradoc age.

In the Wrekin area the quartzites rest unconformably against the
volcanic axis in a nearly continuous band, dipping away from it at
angles of from 30° to 55°, their present position being due to its
elevation. ‘The volcanic rock is a bedded Precambrian tuff, which
reappears in Lawrence Hill and the Hrcal, also accompanied by
quartzites overlain by Hollybush Sandstone. Caer Caradoc belongs
to the same volcanic series, and the quartzites reappear on its S.H.
flank, overlain by Hollybush Sandstone containing Kutorgina cin-

368 Reports and Proceedings—

gulata and Serpulites fistula, above which follow the Shineton Shales,
and next, separated by a fault, the Hoar Edge grits (Lower Caradoc).
The author believes that the apparently conformable succession here
is due to parallel faults. Along the §.HE. flank of the Wrekin the
quartz rock dips 8.E., while the volcanic rocks dip N., and fragments
of the latter are contained in its base. ‘The author is inclined to
think this a friction-breccia, and the junction a faulted one. He
also regards the junction with the Hollybush sandstones as a faulted
one, and maintains that in any case the quartzites are older than the
latter rocks, which are sometimes considered the equivalents of the
Ffestiniog group, and by Mr. Belt to be Menevian. The quartzites
can hardly belong to any part of the Upper Cambrian, and the
author passes on to consider the various positions which they may
be held to occupy, and gives reasons for thinking that they are Pre-
cambrian. The only fossil that has been found in them is a supposed
worm-burrow. In conclusion the author expresses the opinion. that
the Stiper-stones quartzites are of Arenig age.

2. ‘On the Affinities of the Mosasauride, Gervais, as exemplified
in the Bony Structure of the Fore-fin.” By Prof. Owen, C.B., F.R.8.,
¥.G.S., ete.

In this paper the author commenced by discussing the opinions
expressed by different anatomists as to the indications of relationship
furnished by the structure of the fore-limb, and stated that in 1851
he had referred Mosasaurus to a Tribe, Natantia, of the Order
Lacertilia. Since then Prof. O. C. Marsh has published a recon-
struction of the fore-limb of the Mosasauroid Lestosawrus simus, and.
from a comparison of his figure with the bones of the same parts in
Cetacea, Plesiosauria, and Lacertilia, the author showed that the
resemblance in structure was closest with the last-named type, of
which the fore-foot of Monitor niloticus was taken for comparison.
Tn the relative length of the digits and the number and form of the
phalanges, the Mosasauroid fore-foot was shown to agree most nearly
with the Lacertilian type. With regard to the presence of a zygo-
sphene and zygantrum in vertebree of Clidastes, cited by Prof. Cope
in favour of his approximation of the Mosasaurs to the Ophidia and
his establishment of the Order Pythonomorpha, the author remarked
that the trunk-vertebre of the Iguanide show zygosphene and
zygantrum, but with modifications which serve to distinguish the
Jguanian from the Ophidian vertebra, and that until we have the
opportunity of comparing the Mosasauroid vertebrae with those of
both these types, the mere presence of these parts cannot be accepted
as conclusive.

3. “On new Species of Procolophon from the Cape Colony, pre-
served in Dr. Grierson’s Museum, Thornhill, Dumfriesshire; with some
remarks on the Affinities of the Genus.” By H. G. Seeley, Esq.,
F.L.S., F.G.S., etc., Professor of Geography in King’s College, London.

The species described by the author were named by him Proco-
lophon Griersoni, P. spheniceps, and P. platyceps; they are repre-
sented by skulls imbedded in a hard red ironstone matrix, apparently
concretionary, and were collected at Donybrook, Queenstown district,
Cape Colony.

Geological Society of London. 369

With regard to the systematic position and affinities of Procolophon
the author remarked that the presence of two distinct nares shown
in his specimens removed the genus from the family Mononarialia,
of the Order Theriodontia, in which it was placed by its founder,
Prof. Owen. He further discussed in considerable detail the
characters upon which the Order Theriodontia is founded, and
arrived at the conclusion that this group must be regarded as
synonymous with the family Cynodontia, which, with the Dicyno-
dontia and Cryptodontia, make up Prof. Owen’s Order Anomodontia.
The genus Procolophon, displaying no distinguishable canines, does
not possess the chief character of a Cynodont, and the author pre-
ferred to regard it as belonging to a parent type from which the
dental modifications of the Anomodontia have been derived, and,
from its apparent relationship to Hatteria, as forming an extinct
family of the Rhynchocephala. Hence the question arises, whether the
Anomodontiaand the South-African forms described as Dinosaurs might
not be united with the Rhynchocephala to form a subclass of Reptilia.

4, “On the Microscopic Structure of the Stromatoporide, and on
Paleozoic Fossils mineralized with Silicates, in Illustration of
Eozoon.” By Principal Dawson, LL.D., F.R.S., F.G.S.

The fossils included in the group Stromatoporidee occur from the
Upper Cambrian to the Upper Devonian inclusive, and are especially
abundant in the Trenton, the Niagara, and Corniferous formations.
The author regards Stromatopora as a calcareous, non-spicular body,
composed of continuous, concentric, porous lamine, thickened with
supplemental deposit, and connected by vertical pillars, most of
which are solid. The surface shows no true oscula; but perforations
made by parasitic animals have been mistaken for such. From the
structure they could not have been related either to Sponges or to
Hydractinie, and still less to Corals; they are truly Foraminiferal,
and may be regarded as the Paleozoic representatives of Hozoon.
Stromatopora occurs infiltrated with calcite or silica, or with its
structure wholly or in part replaced by crystalline silica or dolomite.
The author concluded his first section with the characters of the
genera which have been included in the Stromatoporide.

In the second part he noticed a number of facts relating to the
occurrence of hydrous silicates, of the nature of serpentine and
loganite, infiltrating Paleeozoic fossils and illustrating the mode of
occurrence and mineralization of Hozoon. Instances of this kind
were said to be exceedingly common, showing that such silicates,
whether originating as direct deposits from water, or as products of
the decomposition of other minerals, are efficient agents in the
infiltration of the pores and cavities of fossils, and have played this
part from the earliest geological periods.

5. “On some Devonian Stromatoporide.” By A. Champernowne,
Esq., F.G.S.

The author’s object in this note was to give some account of the
origin of a fine series of Stromatoporidz presented by him to the
Society. They were all from the Great Devon Limestone at Dar-
tington, near Totnes, and were obtained from a spot in the Pit Park

DECADE II.—VOL. 1Y.—NO. VIII. 24

370 Reports and Proceedings—

Quarry, where the dolomitic rock, instead of being hard and
crystalline, is friable and almost sandy. The Stromatoporida
appear to have grown in the position in which they are found.
They can be traced for a few yards from the friable portion of the
rock, but gradually become merged in the crystalline rock, and then
their internal structure is obliterated. The author noticed the
various Corals, Crinoids, and Brachiopods which occur associated
with the Stromatoporide. The author regarded the Stromatoporide
as a somewhat heterogeneous mixture of organisms, but did not
believe that they were, as had been asserted, originally siliceous.
Some seem clearly to be of a structure like that of the Milleporide.
With regard to Caunopora placenta (Lonsd.) the author quoted Prof.
Phillips’s remarks as to the characters of the tubes traversing its mass.
He had observed in sections from near Teignmouth, that the axis of
the tube is lamelliferous, giving some appearance of a columella.

6. “On a new Species of Loftusia from British Columbia.” By
George M. Dawson, D.Sc., F.G.8., Assoc. R.S.M., of the Geological
Survey of Canada.

The specimens on which the genus Loftusia was founded in 1869
were brought from Persia by Mr. Loftus, and the rock from which
they were derived was conjecturally assigned to the earliest Ter-
tiaries. The species now described (LZ. columbiana) is found in a
limestone probably of Carboniferous age, and occurs in the banks of
Marble Cajon, Frazer River. It appears to be very thick, but may
be repeated by folds. Crinoidal columns and Fusuline have been
sparingly found in it. Where the Loftusia is abundant it becomes
almost the sole fossil, and sometimes occurs as numerously as Glo-
bigerine in the Atlantic ooze.

Loftusia columbiana differs from L. persica in size, its longer dia-
meter averaging about 0-3 inch, and its shorter one 0:19-0-2 inch.
No regular furrowing of the outer surface has been observed, but
some specimens show a tendency to acervuline growth. The struc-
ture is very like that of L. persica as described by Mr. Brady,
although the nucleus is not quite so distinctly cancellated ; the test
consists of a primary layer coiled upon itself, with “ secondary”
septa very oblique to it, and “tertiary” columns expanding at the
outer ends into cross-like “‘ rafters,” supporting the roof formed by
the primary lamina. A loose cancellated growth also depends from
the roof between these rafters, analogous to a more regular structure
observed in L. persica. The usual number of convolutions is about
10, but as many as 17 have been observed.

JI.—June 19, 1878.—John Evans, Esq., D.C.L., F.R.S., Vice-
President, in the Chair.

Important Notice.—The Chairman stated that a letter had been
received from Count Gaston de Saporta, announcing that the Con-
gress of the French Association for the Advancement of Science will
be this year held in Paris from the 22nd to the 29th August. As
President of the Geological Section, M. de Saporta invites Fellows
of the Geological Society to take part in the proceedings of this

Geological Society of London. 371

Congress, which will be followed by two other réunions of ex-
clusively geological interest, at which Fellows of the Society may
be present. Announcements of an intention to attend the Congress,
or to send memoirs to be laid before it, and applications for further
information, may be addressed to the Secretary of the French Asso-
ciation, 76, Rue de Rennes, Paris; or direct to the Comte de Saporta,
Aix-en-Provence, Bouches-du- Rhone.

The following communications were read :—

1. “On the Section of Messrs. Meux & Co.’s Artesian Well in the
Tottenham Court Road, with Notices of the Well at Crossness, and
another at Shoreham, Kent; and on the probable range of the
Lower Greensand and Paleeozoic Rocks under London.” By Prof.
Prestwich, M.A., F.R.S., V.P.G.S.

The well-known boring at Kentish Town in 1856 showed the
absence at that point of Lower Greensand, the Gault being im-
mediately succeeded by hard red and variegated sandstones and
clays, the age of which was at first doubtful, but which were finally
considered by the author to approach most nearly to the Old Red
Sandstone near Frome, and to the Devonian sandstones and marls
near Mons, in Belgium. The existence of some doubt as to this
identification rendered the boring lately made at Messrs. Meux’s
brewery particularly interesting, and the method of working adopted
by the Diamond-boring Company, by bringing up sharply cut cores
from known depths, gave special certainty to the results obtained.
The boring passed through 6523 feet of Chalk, 28 feet of Upper
Greensand, and 160 feet of Gault, at the base of which was a seam, -
3 or 4 feet thick, of phosphatic nodules and quartzite pebbles. —
Beneath this was a sandy calcareous stratum of a light ash-colour,
passing into a pale or white limestone, and this into a rock of oolitic
aspect. Casts and impressions of shells found in this bed showed it
to be the Lower Greensand, whose place it occupied. The boring
was carried further in the hope of reaching the loose water-bearing
sands of this formation, but the rock became very argillaceous, and
when 62 feet of it had been passed through, the bore entered into
mottled red, purple, and greenish shales, dipping at 35° in an
unascertained direction. These beds continued through a depth of
80 feet, when, their nature being clearly ascertained, the boring was
stopped. The fossils of these coloured beds, which included Spzr7-
fera disjuncta, Rhynchonella cuboides, and species of Edmondia,
Chonetes, and Orthis, show them to be of Devonian age. Thus, the
existence of Paleozoic rocks at an accessible depth under London,
and the absence of the Jurassic series, as maintained long since by
Mr. Godwin-Austen, is experimentally demonstrated.

These facts are of interest in connexion with the question of the
possible extension of the Coal-measures under the Cretaceous and
Tertiary strata of the south-east of England. The beds found at the
bottom of Messrs. Meux’s boring are of the same character as the
Devonian strata which everywhere accompany the Coal-measures
in Belgium and the north of France, being brought into juxtaposition
with them by great faults and flexures. The author refers especially

372 Reports and Proceedings—

to a remarkable section at Auchy-au-Bois, in the western extremity
of the Valenciennes coal-field, which is particularly interesting
from its furnishing evidence that the Hardinghen coal-field, between
Calais and Boulogne, is a prolongation of that of Valenciennes, and
because the same strike and a prolongation of the same great fault
observed at Auchy-au-Bois through Hardinghen would carry the
southern boundary of any coal-field in the south-east of England just
south of Maidstone, thence passing a little north of London. Hence
it is in the district north of London that there is most probability
of the discovery of the Carboniferous strata. The extent of country
in which shafts could be sunk to the Paleozoic strata will, however,
be limited by the presence of the water-bearing Lower Greensand,
which probably reaches close to London in the south, reappears in
Buckinghamshire and Bedfordshire, 30 or 40 miles north of London,
and probably extends some distance towards the city under the
Chalk hills of those counties and Hertfordshire.

The nature of the representative of the Lower Greensand in the
boring, and the characters of the fossils contained in it, lead the
author to the conclusion that in it we have a deposit produced near
the shore of the Neocomian sea, here probably consisting of cliffs of
Devonian (or Carboniferous) rock. From these cliffs the calcareous
material which here replaces the usual loose sands of the Lower
Greensand was perhaps derived by the agency of springs; and the
shore-line itself must be situated between the south end of Totten-
ham Court Road and the Kentish Town boring. The sandy beds of
the Lower Greensand will probably be found to set in at no great
distance to the southward, presenting the conditions necessary for
storing and transmitting underground waters. A test boring made
by Mr. H. Bingham Mildmay at Shoreham Place, about 5 miles from
Sevenoaks, and in which the Lower Greensand was met with at
about the estimated depth (450 feet) and furnished a supply of
water, seems to confirm these views.

2. “Notes on the Paleontology and some of the Physical Con-
ditions of the Meux’s Well Deposits.” By Charles Moore, Hsq., F.G.S.

The author remarks that the various deep well-borings around
London have abundantly proved the correctness of Mr. Godwin-
Austen’s inference that the Paleozoic axis of the Mendips is con-
tinued beneath the Secondary rocks of the south-eastern counties.
Mr. Moore has himself shown that where these Paleozoic rocks
finally disappear under the Secondary strata, there are found at
the unconformable junction of the two formations a set of deposits
indicating the existence of very peculiar physical conditions, and con-
taining an admixture of fossils from very different geological horizons.
Hence he was led to inquire whether any trace of similar abnormal
deposits might be found in the deep well-borings of London.

With this view he set to work at washing some of the materials
supplied to him from the Meux’s well, and studying the minute and
often microscopic organisms thus obtained.

The Chalk was not particularly examined; but from a single
small sample of Upper Greensand he obtained numerous Foramini-
fera and Entomostraca, including one Cyprid new to science.

Geological Society of London. 373

The Gault yielded 16 genera and over 30 species of Foraminifera,
and 20 species of Entomostraca, 4 of which are new, together with
many young forms of Gasteropods and Cephalopods.

But the chief interest of Mr. Moore’s investigations centres in the
67 feet of strata intervening between the Gault and Devonian. In
this marly and oolitic-looking deposit he found no less than 8
different kinds of organisms, exhibiting a singular admixture of
marine and lacustrine forms of life. Foraminifera are rare, but
Entomostraca and Polyzoa are very abundant. Some genera are
found, such as Carpenteria, Saccammina, Thecidium, and Zellania, of
which the range in time is greatly extended by these investigations.

The author fully confirms Mr. Etheridge’s reference of the beds in
question to the Neocomian period, widely as they differ in physical
characters from the Lower Greensand strata of the south-east of
England. From a careful study of the nature and condition of
preservation of the minute organisms, he concludes that the deposits
which contain them were formed at first in shallow lacustrine
hollows on the surface of the Devonian rocks now lying buried at
a depth of 1000 feet below London, and that these lakes were
invaded by the waters of the Neocomian sea, with the deposits of
which their sediments were in part mingled, and under which they
were finally buried.

The Chair was then taken by Prof. Prestwich, M.A., F.R.S., Vice-
President.

3. “On Pelanechinus, a New Genus of Sea-urchin from the Coral
Rag.” By W. Keeping, Esq., B.A., F.G.8., Professor of Geology in
the University College of Wales.

In 1855 an Kchinid was described by Dr. T. Wright, from very
fragmentary specimens, under the name of Hemicidaris corallina.
Since that date two very fine specimens have been obtained, both
from Calne, one by Mr. Keeping, sen., now in the Woodwardian
Museum, Cambridge, the other in Dr. Wright’s Collection. These
show the affinities of the HEchinid to be rather with the Echinothu-
ride. The author regards this species as the type of a new genus,
which he names Pelanechinus, and characterizes as follows :—

Test thin, circular, depressed, consisting of (1) transversely elon-
gated coronal plates, (2) apical plates, (8) an actinal system of im-
bricating plates around the month. Interambulaeral areas narrow at
poles, but rapidly broadening towards the equator, with 6-8 rows of
primary tubercles ; the plates narrow, contour rounded, slightly un-
dulating. Ambulacral areas more uniform, equal to 4 of the greatest
breadth of interambulacral areas, with two rows of primary tuber-
cles; poriferous zones broad, pores trigeminal in the equatorial re-
gion. Primary tubercles rather small, smooth, perforated, uniform
over both areas; spines small, hollow. Peristome deeply notched.
Actinal area about 2 of whole test, covered with zones of large im-
bricating plates, with perforations and perforated tubercles. Jaws
large and powerful.

This Echinid has a marked similarity of appearance to Asthenosoma
(Calveria), and the author believes that it also had a flexible test.

4, “Remarks on Saurocephalus, and on the Species which have

O74 Reports and Proceedings——

been referred to that Genus.”' By HE. Tulley Newton, Esq., F.G.S.,
of H.M. Geological Survey.

In this paper the author gives an account of those species of fossil
fishes from American and British Cretaceous strata which have been
referred to the genus Saurocephalus, originally founded by Harlan
in 1880, and regarded by him as showing Reptilian affinities. The
ichthyic nature of the species first described, S. lanciformis, Harl.,
was demonstrated by Prof. Owen. By Agassiz and Dixon certain
large fossil teeth from the White Chalk of Lewes were identified
with Saurocephalus lanciformis ; and the latter also figures an elon-
gated rostrum as belonging to this fish. Dr. Leidy, in 1856, re-
described the original specimen of Saurocephalus lanciformis, and
maintained that the jaws and teeth figured by Dixon do not belong
to the genus Saurocephalus; he proposed for them the new name of
Protosphyrena ferox. He thought also that the rostrum figured by
Dixon belonged to a Sword-fish, and named the species Xiphias
Dixoni. Specimens since obtained by Prof. Cope in America have
proved that the rostrum and teeth actually belonged to the same
fish, for the reception of which and of some American species Prof.
Cope established the genus Hrisichthe. The author maintains that
Dr. Leidy’s name, Protosphyrena, must be adopted for this genus,
which will include the British Protosphyrena ferox (= Erisichthe
Dixoni, Cope) and the American species, P. angulata, anitida, pene-
trans, and ziphioides (Cope). ‘The characters of these species are
discussed by the author. The species known on the Continent as
Saurocephalus albensis and influens, Pict. et Camp., S. dispar, Heb.,
and S. inequalis and substriatus, Miinst., are founded on isolated
teeth, and their affinities are regarded by the author as doubtful.
Saurodon Leanus, Hayes, from the Greensand of New Jersey, belongs
to Saurocephalus, which also includes a species described by Prof.
Cope under the name of S. arapahovius. Teeth erroneously referred
by Agassiz to Saurodon Leanus were regarded by Dr. Leidy as re-
presenting a new genus and species, Cimolichthys levesiensis, and to
this last-named genus the author refers Spinax marginatus, Reuss,
and, doubtfully, Saurocephalus striatus, Ag.

5. “A Microscopical Study of some Huronian Clay-slates.” By
Dr. Arthur Wichmann.

Although a considerable amount of attention has been devoted
during recent years to the microscopical study of clay-slates and
slate-clays, yet in none of the published researches on this subject
has any account of the structure of the clay-slates of Archean age
been given. The author has availed himself of the extensive series
of Huronian clay-slates collected by Major T. V. Brooks in the
country around Lake Superior to supply this deficiency. The suc-
cession and relation of the rocks described have been fully treated
of in the work of Hermann Credner and the publications of the
Geological Survey of Michigan.

The chief object of the author is to discuss the origin of the crys-

1 On this genus see a paper by Mr. W. Davies, F.G.S., in the Grou. Mac. 1878,
for June last, p. 254, Pl. VIII.

Geological Society of London. 370

talline constituents in clay-slates, and at the outset he describes in
detail the microscopical character of clay-slate, of novaculite or
whetstone, and of carbonaceous shales and slates respectively, dwell-
ing more especially on the crystallized minerals which can be de-
tected in each of these rocks, and the nature of the isotropic ground-
mass which sometimes surrounds them. He then points out that
three theories have been advanced to account for the presence of
these crystalline constituents in clay-slates. According to the first
of these theories, the crystals in question are regarded as the product
of chemical action in the ocean in which the original material was
deposited. The second theory attributes the formation of the crys-
talline minerals to processes of metamorphism which have taken
place subsequently to the solidification of the rocks. The third
theory refers them to aggregative action going on in the still plastic
clay-slate mud prior to its solidification. The first of these theories
has been maintained by G. R. Credner, but against it the author
adduces numerous arguments, and especially points out the difficulty
of supposing an ocean capable of depositing from its waters at suc-
cessive periods minerals of such different chemical composition as
chlorite, actinolite, etc. In. opposition to the second theory, which
has received the support of Delesse, the author points out the
existence in the rocks in question of broken crystals, which have
-been recemented by the surrounding clay-slate substance. The
author is thus led to incline towards the third theory, in favour of
which some striking facts, drawn from the microscopical structure
of the rocks, have already been adduced by Zirkel. He admits, how-
ever, that later metamorphic actions are not to be excluded in
seeking to account for the origin of the crystalline constituents of
clay-slates, and points out that four distinct stages must be con-
sidered in the series of changes by which the rocks in question have
acquired their present character :—Ist, the deposition of the mud ;
2nd, the formation of minerals during the plastic state; 3rd, the
separation of materials during solidification ; and 4th, the action of
metamorphic processes.

6. “On a Section through Glazebrook Moss, Lancashire.” By T.
Mellard Reade, Hsq., F.G.S. of

The section described has been exposed in a cutting made by the
Wigan Junction Railway. The moss rests on an almost perfectly
level floor of Boulder-clay, and is at the deepest part about 18 feet
thick. In the 8 or 4 feet at the base are branches, etc., of trees, and
the stools are found resting on and rooted in the Boulder-clay ;
these are of oak or birch. Prostrate trunks were found, one, an
oak, being 46 feet long and 3 in diameter. The surface of the clay
is about 60 feet above O.D. The author thinks the section shows
that the moss originated from the decay of the forest, favoured by
change of climate, and gradually extended itself from the centre
outwards, trees within it at the outer part being much less dis-
coloured than those further in. In the latter part of the paper some
cuttings and borings in the clays and sands are described, and the
asserted occurrence of the trunk of a tree in the Boulder-clay is noticed.

7. ‘On the Tertiary Deposits on the Solimées and Javary Rivers

376 Leports and Proceedings—

in Brazil.”* By C. B. Brown, Esq. With an Appendix by R. Hthe-
ridge, Hsq., F.R.S., F.G.S., and communicated by him.

The author in 1874 had the opportunity of examining some beds
on the Solimées, or Upper Amazon, and the Javary, one of its
tributaries, containing fresh- and brackish-water shells similar to
those found in Tertiary deposits at Pebas, still higher up the river.
The author indicates certain errors into which he considers previous
writers to have fallen, and calls attention to the great extent of
these beds, now demonstrated to occupy a tract of country 300 miles
in length by 50 miles in breadth, and to the enormous change in
the physical features of the region which must have taken place
since their deposition. When this took place, the sea reached pro-
bably 1500 miles west of its present shore-line, covering the
country which is now the valley of the Amazon. The absence of
examples of false-bedding in the deposits leads him to the con-
clusion that they were formed in comparatively still water, into
which flowed numerous streams bearing much vegetable matter,
which has served for the formation of lignitic deposits, the whole
being probably the upper beds of a series deposited under similar
conditions to those of deltas in the present day. In an Appendix,
Mr. Etheridge notices the fossils collected by the author, which
included seeds of Chara, and species of Mytilus (1 new), Anisothyris
(4, 1 new), Lutraria (1), Thracia (1), Anodon (1), Unio (1) Natica ?
(1), Neritina (2 new), Odostomia (1), Hydrobia (1 new), Isa (1),
Dyris (1), Assiminea (1 new), Fenella (1), Cerithium (2 new),
Melania (4 new), and a new Gasteropod constituting a genus
(Alyc@odonta) allied to Alyceus. A single palatal plate of Myliobatis
or Zygobatis (probably derived) was also found.

8. “On the Physical History of the English Lake-district, with
Notes on the Possible Subdivision of the Skiddaw Slates.” By J.
Clifton Ward, Esq., Assoc. R.S.M., F.G.S.

The author traces the physical history of the lake-district from
the commencement of the period when the Skiddaw slate was
deposited. To this succeeded the volcanic Borrowdale series, which
is followed after a physical break by the Coniston Limestone.
Between this and the succeeding Silurian deposits there is little, if
any, break. Thus, in the Lake-district, the break between Upper
and Lower Silurian is physically below the Coniston Limestone,
though paleontologically it is above it.

The Old Red Sandstone period was one of denudation, which was
continued into the Carboniferous period; and perhaps the whole
district was actually covered by the sea during the maximum
depression of the Lower Carboniferous epoch. Since then it has
probably never been submerged, but exposed to continuous subaerial
denndation. The physical significance of the Mell Fell (Lower
Carboniferous) conglomerates receives special attention.

The author, from consideration of the amount of deposition and
rate of denudation, attempts to estimate the period which has
elapsed since the commencement of the record, and sets it down

‘ On this subject see paper by Dr. H. Woodward, in Ann. & Mag. Nat. Hist.
1871, ser. 4, vol. vii. pp. 59 and 101, pl. v.

Geological Society of London. B77

as 62,000,000 of years. He then considers the age of the
Skiddaw slates. From lithological resemblances he is led to cor-
relate the Skiddaw grit with the basement grit in the Welsh Arenig
series, and thus to regard the beds below the grit as the equivalent of
the Tremadoc, and perhaps of part of the Lingula Flags.

The paleontological evidence for the correspondence of the Arenig
series with the whole of the Skiddaw slates rests chiefly on Graptolites
and Trilobites. The author holds that the evidence from the former
is inconclusive, and that from the latter to some extent contradictory,
so that the physical evidence can in no way be overridden by it.

9. “On some Well-defined Life-zones in the Lower Part of the
Silurian (Sedgw.) of the Lake-district.” By J. H. Marr, Hsq. Com-
municated by Prof. T. M‘K. Hughes, M.A., F.G.S.

This paper treats of the zones of fossils occurring between the
Coniston Limestone and Coniston Grits, with a view of establishing
a boundary between the Cambrian and Silurian formations. In the
lake-district beds the genus Phacops is very abundant, one or more
species of its subgenera characterizing each fossiliferous formation.
The zones thus indicated are found to hold good when the organic
remains as a whole are considered. The author separates the Ash-
gill shales from the Coniston Limestone, giving separate lists of
fossils to show the paleontological difference, from which it appears
that but few (and those the very common Bala fossils) are common
to both, while the most characteristic Ashgill fossils do not occur in
the Coniston Limestone. They indicate that the Ashgill formation
is Upper Bala. It is very irregular in thickness, and the author
thinks this due to an unconformity above the Ashgill beds. Here
the author agrees with Prof. Hughes in placing the base of the
Silurian. He gives lists of the fossils in the basement bed and the
Stockdale Shales, and points out that their facies is distinctly
Silurian. Very few fossils are common to them and the Coniston
Limestone or Ashgill Shales. Hence there is here both a physical
and a paleontological break, so that the division between Cambrian
and Silurian should be placed at this horizon. A detailed description
(with lists of fossils) is given of the Coniston Flags and Coniston
Grits. An appendix contains some paleontological notes on some
species of the genus Phacops.

10. “On the Upper Part of the Bala Beds and Base of Silurian in
North Wales.” By F. Ruddy, Esq. Communicated by Prof. T.
M‘K. Hughes, M.A., F.G.S.

The author describes a series of sections in the upper part of the
Bala and the succeeding beds, and gives lists of fossils. Details of
the various beds between the Bala and Hirnant Limestone are
given, above which come soft blue shales underlying Tarannon
shales, when fossils cease until the base of the Wenlock is reached.
The author has been able to trace the Hirnant Limestone and grit
considerably beyond the limits of the Hirnant valley. The sections
at Cynwyd (to the west of Corwen) are described. Here occur the
equivalents of the Bala Limestone and beds above this up to the
level (probably) of the Hirnant Grit.

378 Correspondence—Mr. G. J. Hinde—Rev. E. Maule Cole.

CORRESPONDENCE.

ARBUSCULITES ARGENTEA, MURRAY.

Str,—Though unable to refer to Murray’s description of this
fossil, the quotations given from it by Mr. R. Etheridge, jun., in
the June Number of the Magazinz, p. 269, recalled at once to my
mind the characters of a somewhat similar fossil I discovered some
years since in rocks of Lower Carboniferous age at Arsaig in Nova
Scotia. On the shore at this place, near McAras Brook, there are
exposed beds of a dark, Oolitic limestone, which, in places, are
interpenetrated in all directions with bright glistening threads
“yesembling broken bits of silver-wire.” These occur in curved
fragments of about two or three lines in length and about one-tenth
of a line in thickness; they are solid, and, so far as I can see, neither
grooved nor branched, and in these respects they differ from the
forms described by Murray.

The only other fossils visible in the same beds are very poorly
preserved casts of Producti; their presence supports the opinion
expressed by Mr. Etheridge that these glistening threads are merely
the long spines of this Brachiopod; but if this is the case, it is very
peculiar that, whilst the shells of the Producti have to a large extent
disappeared, their spines should have been preserved in such great
numbers and such perfect condition. On this supposition too, it is
remarkable that similar spines (?) should not have been noticed in
limestones in which Producti abound, for in the beds mentioned they
are very conspicuous objects. Inclosed are two small pieces of the
rock, showing these spines(?). On one is what appears to be the

expanded base of attachment. Gero. JENNINGS HINDE.
Toronto, June, 21st, 1878.

AGE OF THE ROCKS OF MONTE GENEROSO.

Srr,—I have several times had the pleasure of ascending Monte
Generoso, a mountain easy of access, which lies between the Lakes
of Como and Lugano, and from which one of the finest views on the
continentis obtainable. After winding up through chestnut woods from
Mendisio for some four miles, the pathway ascends a somewhat steep
incline in zigzags. The rocks here are remarkably white and dazzling
and might be almost mistaken for chalk. Forsome 40 ft. or more below,
they are coloured red, similar to the Red Chalk in Yorkshire.

On the last occasion of my visit, 1 met with a French geologist
at M. Paston’s Hotel near the summit, and from him IJ obtained some
information about these rocks which had excited my curiosity, but
not enough to satisfy me as to their position relative to English
strata. He classed them as follows :—

JURA LOMBARD.

Majolique
Caleatre rouge
Caleaire greés
Calcatre noir

Conglomerat Marneux

Obituary—The Rev. W. Branwhite Clarke. O79

Can you, or can any of your readers give me some more information
on this subject ? Epw. Mavute Cos.
Wetwane VICARAGE, YORK.

P.S.—Can you recommend to me any notices on “ Red Chalk” in
England ?—E. M. C.

The Rev. E. M. Cole will obtain the information he seeks, by
consulting the following papers, which are picked out of a list still
in course of formation.

Blake, Rev. J. F —Proceed. Geol. Assoc. vol. v. p. 232, ete.

* Judd, J. W.—Quart. Journ. Geol. Soc. vol. xxiii. p. 227.
Phillips, Prof. J. Geol. of Yorkshire, 3rd edit. p. 75.
Seeley, Prof. H. G.—Ann. and Mag. of Nat. Hist. 3rd series, vol. vii. p. 233,
1861; Quart. Journ. Geol. Soc. vol. xx. p. 327.
Taylor, Richard.—Phil. Mag. 1828, vol. 61, p. 81.
Wiltshire, Rev. T.—Quart. Journ. Geol. Soc. vol. xxv. p. 185.
For Analysis of Red Chalk see—
Church, A. H.—Chemical News, vol. 31, p. 199; or Gzou. Mae. Vol. II. p. 331.

B. B. W.

CASsFID Cfo NIS NZ

THE REV. WILLIAM BRANWHITE CLARKE,

M.A., F.R.S., F.R.G.S., F.G.S., ETC.
Born 2 June, 1798. Diep 17 June, 1878.

WE regret to record the death of another veteran geologist, the
“Father of Australian Geology,” the Rev. W. B. Clarke, which took
place at his residence near Sydney, in the eighty-first year of his
age. Mr. Clarke was born at Hast Bergholt, Suffolk, on the 2nd
June, 1798, and was partly educated at Dedham Grammar School.
He entered Cambridge in 1817, becoming a member of Jesus
College, took his B.A. in January, 1821, and became M.A. and
Member of Senate in 1824.

From 1821 to 1824 he acted in his clerical capacity at Ramsholt
and other places, and during this period made fifteen distinct geolo-
gical and other excursions on the Continent, in addition to those
prosecuted by him in this country. During the years 1830-31 Mr.
Clarke was present at many of the scenes of the Belgian War of
Independence, and the last siege of Antwerp. His clerical duties
were continued up to the year 1839, when he left for New South
Wales, with the object of examining the physical structure of the
country, and regaining health lost during a severe illness. From
the time of his arrival till 1844, Mr. Clarke was in clerical charge
of the country from Paramatta to the Hawkesbury River, and for a
portion of the time conducted the King’s School. In that year he
undertook the charge of Campbelltown, but in 1847 he became
minister of Willoughby, which he held till 1870, then retiring, after
nearly fifteen years’ service in the church, with a testimonial from his
parishioners, expressive of their sympathy and respect.

380 Obituary—The Rev. W. Branwhite Clarke.

Mr. Clarke’s literary labours were numerous and varied. In 1829
a series of poems and translations were published, entitled ‘Lays
of Leisure,” in 1819 a poem, entitled “Pompeii,” in 1822 ‘The
River Derwent, and other Poems,” and in 1828 “ Recollections,” a
poetic commemoration of a visit to Mont Blanc; and other works of
a religious nature. Mr. Clarke’s valuable services to the Govern-
ment commenced in 1840, when he made his first journey to the
southward, through the Illawara district. The result of this, and
his other journeys, geographical as well as geological, will be found
recorded in a clear and concise manner in his chief work,! and in
the various Parliamentary Blue Books? published by Authority, to
say nothing of the fifty-three papers accredited to his name in the
Catalogue of Scientific Papers’ of the Royal Society. In addition
to the list there given, we are acquainted with many others, and it
may be mentioned that some of Mr. Clarke’s most interesting com-
munications were made to the leading Sydney newspaper, the Sydney
Morning Herald, which we regret are not preserved in a more
lasting form.

Mr. Clarke’s labours as a geologist and zoologist commenced some
time before his departure from this country, for in 1828 a paper,
“On the Construction of Geological Hammers,” appeared, and again
in 1837, “On the Geological Structure and Phenomena of Suffolk,
and its Physical Relation with Norfolk and Essex,” with several
others. One of his first papers on Australian geology was, we
believe, “On the Occurrence of Atmospheric Deposits of Dust and
Ashes; with Remarks on the Drift Pummice of the Coasts of New
Holland,” in 1842.

With the ‘Discovery of Gold in Australia,’ and the ‘Age of the
N. 8. Wales Coal-beds,’ the name of W. B. Clarke will always be
associated. This is not a fitting time to enter into the merits of his
controversies respecting his claim for priority to the former, or his
views on the latter question; let it suffice, however, that excepting
Count de Strzelecki, the palm has been awarded him in the Gold
question by Prof. Geikie, F.R.S., in a late work,‘ whilst the second
may, to a certain extent, still be said to remain an open question.
Some of the more important subjects which engaged Mr. Clarke’s
attention were the occurrence of gold in granite, the occurrence of
the diamond in N. S. Wales, and the discovery of tin in Australia.
The occurrence of the diamond appears to have been known to
Clarke as early as September, 1859; whilst under this head may be
mentioned a most exhaustive and critical paper, the Natural History
of the Diamond, delivered in the form of two Anniversary Addresses
to the Royal Society (N.S. Wales) on the 25th May, 1870, and 22nd
May, 1872, respectively. Little doubt appears to exist that we owe

1 Researches in the Southern Goldfields of New South Wales. 2nd ed. 8vo. Sydney.

2 Papers relative to the Discovery of Gold in Australia, presented to both Houses
of Parliament, by Command of Her Majesty. Parl. Blue books. Folio, London.

3 Catalogue of Scientific Papers, Royal Society, vol. i. 1867; vol. vii. 1877.

* Life of Sir Roderick I, Murchison, Bart., K.C.B., etc., by Archibald Geikie,
LL.D., F.R.S., ete. London, 1875. Two vols. 8vo. (vol. ii. p. 185).

Obituary—The Rev. W. Branwhite Clarke. 381

the first actual discovery of tin in Australia to Mr. Clarke, as detailed
by himself in a paper ‘On Mining’ contributed to the Sydney Morning
Herald, August 16th, 1849. He also reported on the occurrence of
Cinnabar in N.S. Wales, and, by means of acollection of fossils, made
with the assistance of W. Hardy, Hsq., first elicited the fact of the
occurrence of rocks of Silurian age on the flanks of the Dividing
Range, a discovery for which he was highly complimented by the
late Sir R. I. Murchison. This collection was examined and deter-
mined by the late Messrs. Lonsdale and Salter, but a second and
more extensive one, gathered from all parts of N. 8. Wales by Mr.
Clarke, and his friends, has lately formed the subject of a detailed
and successful work by Prof. de Koninck.'

Mr. Clarke paid a geological visit to Tasmania in 1856, and an-
other in 1860, to examine the country around Fingal and the Don
River. The interest he took in all matters connected with Colonial
Geology cannot be better shown than by the fact that he success-
fully recommended no less than three Government Geologists to
their respective colonies, viz. the late Messrs. R. Daintree, and C.
D’Oyly H. Aplin, to North and South Queensland, and Mr. C. Gould
to W. Australia, who was succeeded by Mr. H. Y. L. Brown. We
believe Mr. Clarke was also instrumenial, at all events to a consider-
able extent, in the appointment of Mr. C. S. Wilkinson, F.G.S.,
Government Geologist for N.S. Wales. Just as he took an interest
in Colonial Surveys, so Intercolonial Exhibitions appear to have occu-
pied much of his time, taking particular interest in the Geological Sec-
tions, and frequently contributing articles to the official catalogues on
the resources of his adopted country. He was a member of the N. S.
Wales Commission of the Paris Exhibition of 1867, the Intercolonial
Exhibition of 1870, and the Philadelphia International of 1877.
The Rev. W. B. Clarke was appointed in 1839, by Sir G. Gipps, a
Trustee of the Australian Museum, Sydney, and of the Free Public
Library. Sir C. Fitzroy placed his name on the first list of Fellows
of Sydney University, an honour, however, never accepted, we be-
lieve. The Presidential and Vice-Presidential chairs of the Royal
Society of N. 8. Wales were several times filled by Mr. Clarke; in-
deed in the reconstitution of that Society, a short time since, he took
a most lively interest. The Geological Society of London elected
him a Fellow in 1826, and awarded him the Murchison Medal in
1877, “in recognition of his remarkable services in the investigation
of the older rocks of New South Wales.” By the Royal Geographi-
cal Society he was elected a Fellow in 1865, and his name is to be
found amongst the list of members of the Société Géologique de France,
and the Corr. Members of other Continental Societies. Mr. Clarke was
elected a Fellow of the Royal Society in June, 1876, for ‘the important
part taken (by him) in the refounding of the Royal Society of N. §.
Wales, and in the promotion of Scientific Knowledge in the Colony.”
We believe Mr. Clarke was engaged, only shortly before the com-

1 Recherches sur les Fossiles paléozoiques de la Nouvelle-Galles du Sud (Australie).

Par L. G. de Koninck, D.M. Bruxelles (2 vols. 8vo. pt. 1, text and atlas, 1876;
parts 2 and 3, text and atlas, 1876-77).

382 Obituary—Dr. Thomas Oldham, F.R.S.

mencement of the attack which resulted in his death, on a Geological
Map of N. S. Wales, and on a second edition of his “Southern Gold
Fields.” The name of W. B. Clarke requires no encomiums from us;
but when we say, as we think we may safely do, that more
than half his papers and reports have been written with the view
to the development of the mineral resources of his adopted country
and the well-being of his fellow-colonists, some idea may be gathered
of the debt N. 8. Wales owes to the memory of the Rev. W. B.
Clarke. Few are aware of the immense amount of work per-
formed during his various explorations, but it is stated that he has
officially reported on no less an area than 108,000 square miles of
territory.—R. E., jun.

[For some of the facts connected with the earlier career of the Rev. W. B. Clarke
we are indebted to extracts from an Australian contemporary. |

THOMAS OLDHAM, A.M., LL.D., F.R.S., F.G.S.,
LATE DIRECTOR OF THE GEOLOGICAL SURVEY OF INDIA.
Born May, 1816, Diep 17 Juny, 1878.

Derata has just deprived us of another well-known and eminent
geologist, who was the founder of and for twenty-five years occupied
the arduous and important post of Superintendent of the Geological
Survey of our Indian Empire, probably the greatest geological
undertaking carried on by the British Government.

Dr. Oldham was the eldest son of the late Thomas Oldham, Hsq.,
of Dublin, in which city he was born in May, 1816, and where he
was educated at a private school, and entered Trinity College, Dublin,
before he was sixteen years of age.

After obtaining his B.A., he devoted 1887-88 to special studies of
engineering in Hdinburgh, where he also applied himself to acquiring
a sound knowledge of geology and mineralogy under Prof. Jamieson,
with whom he formed a life-long friendship. Subsequently he was
engaged in some extensive engineering works in Edinburgh.

Returning to Ireland in 1859, he became principal Geological
Assistant to General (then Captain) Portlock, R.E., at that time in
charge of the Geological Department of the Ordnance Survey of
Treland, and with whom he surveyed the counties of Derry and
Tyrone, and was largely engaged in the preparation of the report on
those counties, published in 1843. Subsequently he became Curator
and Assistant Secretary to the Geological Society of Dublin, and
Assistant Secretary to the Institute of Civil Engineers of Ireland.

In 1844 he was appointed Assistant-Professor of Engineering in
Trinity College, Dublin, under Prof. J. MacNeill. In 1845 he
succeeded Prof. Phillips to the chair of Geology in Dublin Uni-
versity. In 1846 he became Lecturer to, and in 1848 President of,
the Geological Society of Dublin.

Between 1844 and 1849 he communicated no fewer than twelve
papers to the “British Association” and the “Dublin Geological
Society’s Journal,” all bearing on Irish Geology and Paleontology.
On Ist July, 1846, he was appointed Local-Director for Ireland of the

Obituary—Dr. Thomas Oldham, F.R.S. 383

Geological Survey of the United Kingdom, which he held until 14 Nov.,
1850, when he was nominated to the charge of the Geological Survey
of India by the Hon. the Directors of the Hast India Company, ar-
riving in Calcutta early in 1851.

Those of our readers who are acquainted with the climate, the
physical features, and the vast territorial extent of our Indian
Empire, will more readily appreciate the onerous responsibility un-
dertaken by Dr. Oldham to inaugurate and set in motion the ma-
chinery for so large and important a department of the Indian Civil
Service.

With only a small staff of about twelve assistants he set resolutely
to work, and at the end of ten years from the commencement of the
Survey he was able to show an area, carefully mapped and coloured
geologically, more than twice the extent of the whole of Great Britain,
principally in Bengal and Central India.

One of the chief objects of the Director was to ascertain, by care-
ful examination and mapping, the extent of the Indian Coal-measures
and the quality of the Coal. The best appears to be the Assam
Coal, which lies near the river Brahmapootra; but extensive fields
of coal exist, though by no means distributed generally over the
Indian Empire, but almost entirely concentrated in a double band of
coal-yielding deposits, which, with large interruptions, extend more
than half-way across India, from near Calcutta towards Bombay.

In 1867 Dr. Oldham presented an elaborate Report to the Secre-
tary of State for India, “On the Coal Resources of India,” but no
fewer than sixteen separate memoirs on the various Coal-fields have
been published in the “ Memoirs,” with Maps, viz. :—

1. On the Coal and Iron of Cuttack. 10. Karanpaéra Coal-fields.
2. On the Structure and Relations of the | 11. The I'tkhtri Coal-field.
Talcheer Coal-field. 12. The Daltonganj Coal-field.
3. On the Ranigunj Coal-field. 18. The Chopé Coal-field.
4. On the Coal of Assam. 14, The Satpura Coal-basin.
5. The Jherria Coal-field. 15. The Coal-fields of the Naga Hills,
6. On the Bokaro Coal-field. x bordering Lakhimpur and Sibsagar
7. On the Ramgurh Coal-field. Districts, Assam.
8. Kurhurbari Coal-field. 16. The Wardha Valley Coal-field,
9. Deoghur Coal-field.

In 1862-64 he published, in conjunction with Prof. John Morris,
M.A., a memoir, “On the Fossil Flora of the Rajmahal Series”
(Memoirs Geol. Surv. India), illustrated by numerous plates of the
Zamia-like plants occurring in these Plant-bearing beds.

In 1868 he communicated a paper to the Geological Society of
London, “On the Occurrence of Rocks of Upper Cretaceous Age in
Eastern Bengal.”

A grand feature of the Geological Survey of India is its publi-
cations, which, under Dr. Oldham’s administration, had attained to an
extent and importance unsurpassed even by the magnificent volumes
issued by the United States Surveys, and distributed with the same
liberality.

These publications are of four kinds, viz. :—

384 Obituary—Dr. Thomas Oldham, F-RB.S.

1. Annual Reports, commenced in 1858.

2. Records, issued quarterly, containing brief reports and papers forming abstracts
of more detailed work, and notices of recent discoveries, ete. Royal 8vo.
About 11 volumes published, commenced in 1868.

3. Memoirs, in royal 8vo., illustrated by Plates and coloured Maps of the several
districts, of which 14 volumes have appeared, commenced in 1859.

4. The Paleontologia Indica, being figures and descriptions of the Organic Re-
mains obtained during the progress of the Geological Survey of India. Kleven
separate series published.

Being in England in 1867, Dr. Oldham attended the Meeting of
the British Association at Dundee, and presented an elaborate Report
on the Geology of India.

Dr. Oldham’s last work, in connexion with the Geological Survey
of India, was to complete the transfer of the very extensive collections
and library from the former Indian Geological Survey Office to its
new quarters in the large Imperial Museum of Calcutta, where they
are now favourably located under the present able Superintendent,
Mr. Henry B. Medlicott, M.A., F.R.S., F.G.S.

Dr. Oldham was chosen an M.R.I.A. in 1842.

He was elected a Fellow of the Geological Society of London in
1843; and of the Royal Society in 1848.

He was elected a Member of the Royal Asiatic Society of Bengal
in 1857, serving fourteen years on the Council and four times
elected its President. A bust of Dr. Oldham was obtained by its
members and placed in the Society’s rooms.

He received the Gold Medal of the Royal Society in 1875; the
Emperor of Austria also presented him with a gold medal for his
eminent geological labours in India.

He was an honorary or corresponding Member of the Imperial
Academy and of the “Isis” Society of Dresden; of the Imperial
Society of Naturalists, Moscow; of the Royal Geological Society
of Cornwall; of the Geological Society of Edinburgh; and of the
Zoological Society of London.

He was the discoverer in 1849 of Oldhamia in the Cambrian rocks
of the Wicklow Hills, Ireland (named after him by Prof. Edward
Forbes), the then oldest known fossil organic remain.

Tn 1850 he married Miss L. M. Dixon, daughter of William Dixon,
Esq., of Liverpool, by whom he had five sons and one daughter.

Since Dr. Oldham’s retirement from the post of Superintendent of
the Geological Survey of India, he has resided at Eldon Place,
Rugby. He was lately appointed Hxaminer in Geology to the
University of London, and had fulfilled a similar office to the Indian
Civil Service College at Cooper’s Hill. His final illness was of
brief duration, his last hours of active work being spent in reviewing
Barrande’s Cephalopoda of Bohemia, and F. V. Hayden’s grand Geo-
logical and Geographical Atlas of Colorado, both of which will be
found in the present Number. But the friendly hand that penned
them did not live to correct the proofs. Adopting the words of one
of his colleagues, we may truly say, that, ‘in Dr. Oldham’s death we
have to regret the loss of one who was a good man, a faithful friend,
and a profound observer of Nature.”

GEOL. MAG. 1878. NEw SERIES. DECADE IL. VOL. V. PLATE X.

C.L.Griesbach del *WWest& Coump

Arctic Fossils from Bee chey Island, x

THE

GEOLOGICAL MAGAZINE.

NEW SERIES. DECADE II. VOL. V.
No. IX—SEPTEMBER, 1878.

OF EGEIN Ay SAG re ree aS.

——+>—__

J.—Nores on some Arctic Sizurtan oR DEvontan (?) Fossins From
Brrcury IsLAND, BROUGHT HOME BY THE §.Y. “ Panpora” IN
1875, anD FRom Port Dunpas, LANcAstTER SouND, BY AN EARLIER
EXprEpition 1n 1853."

By Henry Woopwarp, LL.D., F.R.S., F.G.S.,
of the British Museum.

| (PLATE X.)
AM indebted to my friend, Mr. Thomas Crowther Brown, of
Further Barton, Cirencester, for placing in my hands some time
since certain Arctic Corals (brought home in 1853 or 1854"), for
illustration, to be afterwards deposited in the Geological Department
of the British Museum. Some time previously I had also received

a small but interesting series of specimens from Beechey Island,

collected by Dr. A. Horner, the Medical Officer to the S.Y. ‘‘Pandora”

(Captain Sir Allen Young), and by the Artist to the Expedition,

G. R. De Wilde, Esq.; these latter were collected in August, 1875.

I should not have undertaken to notice these myself but for the
valuable aid kindly afforded me by my friend Mr. Robert Ktheridge,
F.R.S., and upon going into the Bibliography of these Arctic fossils,
I found that the late Mr. J. W. Salter, Prof. Haughton, and others,
had already noticed the greater part of them, and there is con-
sequently little or no need to do more than foliow in their steps.

In June the Geological Department of the British Museum was
enriched by the collections made by Captain H. W. Fielden, R.A.,
F.G.S., and Dr. R. W. Coppinger, R.N., of H. M. S. “ Alert” and
«Discovery ” (Captain Sir George Nares), and described by Mr. R.
Ktheridge.”

In July the Museum of Practical Geology transferred to the
British Museum a series of specimens collected by Admiral Om-
manney, R.N., Captain Austin, R.N., Dr. Sutherland, Captain Penny,
and others in their Voyages to Wellington Channel in 1850-51 (in
search of Sir John Franklin), and described by Mr. J. W. Salter,
F.G.8., in Sutherland’s Journal (Appendix to vol. ii. Plates v. and
vi.) ; most of these are from Cape Riley and Beechey Island. There
are also a number of fossils from Depot Point, Albert Land, and

1 Probably by some of the officers of the “ Phoenix” (Captain Inglefield), which
visited Beechey Island both im 1853 and 1854, making two summer trips, bringing
back with her on the second voyage part of the ‘‘ Belcher Expedition.”

See Mr. Etheridge’s paper in Quart. Journ. Geol. Soc. 1878, vol. xxxiv. p. 568,
plates xxv.—xxix.

DECADE II.—VOL. V.—NO. IX. 25

386 Dr. H. Woodward—On some Arctic Fossils—

Exmouth Island, besides several from Beechey Island brought home
by Captain Sir Edward Belcher, C.B., 1852-54, and by Captain
Inglefield (1858-54), described by Mr. Salter in the Appendix to
“The Last of the Arctic Voyages” by Captain Sir HE. Belcher, R.N.
(London, 1855, vol. ii. p. 877, pl. xxxvi.).

Those from Albert Land, etc., are of Carboniferous age, consisting
of Corals, Brachiopoda, etc., Clisiophyllum, Zaphrentis, Syringopora,
Fenestella, Spirifer, Productus 2 sp., etc. Those from Cape Riley
and Beechey Island, both sides of Wellington and Queen’s Channel,
Seal and Cornwallis Islands, are of Silurian age, and some few are
perhaps Devonian.

Writing of Beechey Island, Dr. Sutherland observes :—“ Geo-
logical specimens were obtained in great abundance. Favosites,
Catenipora, Cyathophyllum, Porites, and Fucoid impressions were
very common forms of organic remains. At Cape Riley, and also
on Beechey Island, Favosites gothlandica was found almost every-
where in great abundance, but especially at the latter place, where
it occurs in siti.”

1. Strephodes? Austini, Salter. Pl. X. Fig. 1.

Appendix to Sutherland’s Journal of Captain Penny’s Voyage to Wellington
Channel in 1850-51. London, 1852. Geology by J. W. Salter, p. ccexxx., pl. 6,
figs. 6, 6a. magnified. ;

“This fine coral (writes Mr. Salter), which we dedicate with great
pleasure to the gallant commander of the Expedition, is one of the
most frequent species. It occurs in the form of rounded masses
from an inch to several inches in diameter, covered on all sides with
stellate cells—at first sight looking very like the Astree of the
present seas. The internal structure, however, as of nearly all the
corals of the older rocks, is quite of another order. . . . Prof.
M‘Coy prefers to regard this as a Olisiophyllum rather than a
Strephodes from the internal structure ; it is, however, so imperfectly
shown in the sections I was able to make, and the twisting of the
lamellee is so conspicuous, that I leave it here for the present.” ?

“Surface covered by hexagonal or pentagonal cells, of various
sizes, the larger ones frequently four lines across, the smaller ones in
groups of two, three or more, at the angles of the others. The
extreme edges of the cups are thin and crenulated, their sides
thickened and sloping steeply. Ina large star they are radiated by
about 30 or 40 equal blunt lamelle, which extend to the base, and
about half of them are there united in bundles of three or four, and
are twisted upon the surface of a low boss which rises from the
centre. The lamelle are united everywhere by frequent vesicular
plates. A transverse section below the cup shows narrow, but
distinct, divisional walls between the cells, and the lamelle twisted |
in the middle and united loosely by the vesicular tissue. The
‘intermediate ones in the section appear shorter than they are in the
cup. A longitudal section shows the vesicular plates arched a little
upwards in the middle under the boss, then downwards, and again

1 On a reconsideration of these Paleozoic Corals, probably it may be found possible
to bring Strephodes and Lonsdalia near, or even to unite them together.

From Beechey Island and Port Dundas. 387

inclined upwards in the outer area in two or three rows of cells. In
these sections both the lamelle and the transverse plates are thin,
and the former are wavy.”

Localities.—Cornwallis, Beechey and Griffith’s Islands.

Our specimen, Pl. X. Fig. 1, is from Beechey Island, and was
collected and brought home by Dr. A. Horner, of the 8. Y. “« Pandora”
(Capt. Sir Allen Young, R.N.). It is clearly a young example, the
corallites not having increased by calycial gemmation many times, so
as to form such a fine, evenly-rounded composite mass as that Tepes
sented in Fig. 2.

‘With reference to the fine rounded composite Coral, Plate X. Fig.
2, I was greatly perplexed for some time, and was almost inclined
to refer it to the genus Acervularia; but after a more careful exami-
nation, and by comparing it with numerous other specimens, I have
been led to the conclusion that it is merely a Strephodes Austint, in
which the extremely sharp crenulated edges dividing the calices
from one another, which in young and unworn specimens (as in
Fig. 1) stand boldly up in hexagonal or pentagonal lines, have been
removed by weathering over the whole upper surface, exposing
thereby the lower wall of the calices where they are thickened by
the septal radii and strengthened by numerous interseptal dissepi-
ments. The sides of the calices are in sume instances worn down to
a level with the columella, giving the Coral the appearance of a well-
(acid-)developed Acervularia luxurians from Dudley; but this is
deceptive, for on examining the margins of the specimen, the divid-
ing ridges between the calices are seen nearly as well preserved as in
Fig. 1, changing entirely the character of the specimen. Several
similar rounded masses are in Sutherland’s Collection from Beechey
Island, etc. This specimen is interesting as having been brought
from Port Dundas, which, like Cape Riley, is on the South Coast of
N. Devon, but 200 miles to the Hastward, on the N. shore of Lancas-
ter Sound, Lat. 75° N. It was presented to the British Museum by
Thomas Crowther Brown, Esq. Probably brought home by one of
the crew of the ‘‘ Phoenix” (Capt. Inglefield), 1853-54.

2. Favosites polymorpha, Goldf. Pl. X. Fig. 3.

Goldfuss, Petrefacta Germanie, t. 27, fig. 2-4.

Favosites cervicornis, and F. dubia, Edw. Arch. Mus., and Edw. and Haime, Brit.
Foss. Corals, t. 48, fig. 2.

Appendix to Sutherland’s Journ. (Geology), by J. W. Salter, p. ccxxviil. pl. 6,
figs. 9 and 9a. magnified.

Mr. Salter writes: “ Well-preserved specimens are frequent; and
both the polymorphous (fig. 9) and branched varieties are found at
Griffith’s Island.

«The tubes are by no means of equal size,—numerous small ones
occurring between the others. The edges are somewhat thickened.
Internally the tubes are sometimes cylindrical and smooth, at others
more prismatic. They are sometimes faintly striated inside. The
pores occur in single rows at wide distances apart. The transverse
diaphragms are not visible in these specimens.” Mr. Salter alludes
also to another specimen which agrees well with the F. crassa of
M‘Coy.

388 Dr. H. Woodward—On some Arctic Fossils—

Localities—Griffith’s Island, Cape Riley and Beechey Island.
Leopold’s Island (frequent).

Fig. 3 was obtained by Dr. Horner of the S.Y. “Pandora” from
the shore of Beechey Island, August 25, 1875.

3. Favosites Gothlandica, Linn. sp. Pl. X. Fig. 4.

Oorallium Gothlandicum, Linn., Calamopora Gothlandica, Goldf. Petref. Germ.
t. 26, fig. 3, and C. balthiea, fig. 4.

This is a very common species, having been brought home by Dr.
Horner (‘‘ Pandora”), and also by Captains Austin of the ‘“ Resolute.”
and Ommanney of the “Assistance,” and by Captain Penny. Mr.
Salter finds it to be quite identical with Goldfuss’s figure.

“On the same specimens,”’ he writes,’ “‘a single or double alter-
nating row of pores may be seen on each face and the distance
between the transverse partitions (diaphragms) varies much; in the
same tube we have, within a very short distance, 5, 4, 3, 2, and
13 diaphragms in the space of one diameter. The columns also
vary much in size.”

Localities—Griffith’s, Cornwallis, Leopold and Beechey Islands,
very widely distributed.

4. Cyathophyllum? Pickthornii,? Salter, sp. Pl. X. Figs. 5 and 6.

Strephodes Pickthornit, Salter, Sutherland’s Journal, vol. ii., Appendix, p. cexxx.
plate 6, fig. 6.

In MM. Edward’s and Haime’s Monograph on British Fossil
Corals, p. 232, the authors observe: “We are inclined to consider
the Strephodes gracilis, of M‘Coy, as belonging to the genus Cyatho-
phyllum.” We cannot but think that Strephodes Pickthornii should
also be referred to that genus. From a large number of specimens
examined by us in the Arctic collections already mentioned, it
certainly does not affect the mode of aggregate or composite growth
attributed to Strephodes; all the individuals being found growing
distinct even when placed closely together in the same rock-mass.

Mr. Salter describes this species as follows: ‘The tube is short,
conical, and longitudinally striated ; sometimes annulated and rugose
in growth: and it grows rapidly in breadth,—in the length of an
inch and a half attaining an inch in diameter. The cup is very
deep, its sides formed of about 56 narrow lamellz of equal size,
connected by cross-bars, which are the edges of vesicular plates.
Half of these lamelle stop short at the bottom of the cup, but the
rest cross a shallow depression, and are then twisted a little into
bundles, and united on the crown of a low boss, which is not nearly
elevated enough to constitute it a Clisiophyllum. At first sight the
coral looks like a Petraia,? but the vesicular plates between the
numerous lamelle removes it from this genus.”

Localities.—Cape Riley and Beechey Island, Griffith’s and Corn-
wallis Islands.

Fig. 5 on Plate X. was obtained by G. R. De Wilde, Esq. (of the
« Pandora”), at Beechey Island, in 1875, and is now in the British

1 Appendix to Sutherland’s Journal, p. ccxxviil.

2 Named after Mr. Pickthorne, surgeon of the ‘“‘ Pioneer.”

3 Some of the specimens marked 8. Pickthornii may belong to a species of
Petraia ; they are, however, too much weathered to be safely determined.

From Beechey Island and Port Dundas. 389

Museum. Fig. 6 is a larger but much weathered specimen from
Port Dundas, N. Devon, lat. 75°, 200 miles to the East of Cape
Riley. This specimen was presented to the British Museum by
Thomas Crowther Brown, Esq., of Cirencester.

In many of these corals, which have been partially silicified, the
limestone has frequently been dissolved out, leaving cavities in the
fossils.

5. Alveolites ? arctica, sp. n., H. Woodw. PI. X. Fig. 7.

This small ramose coral occurs in considerable abundance in the
shaly limestone of Beechey Island; but few specimens have the
calices preserved, -and they are more widely separated than in
Alveolites ? seriatoporoides, Hdw. & H.

The specimen, a part of which has been drawn on our Plate
(Fig. 7), is covered on both surfaces with the small branching stems
of this Alveolite, and the transverse section shows the interior of the
rock to be similarly crowded.

Stems, mostly cylindrical, about 1 mm. in diameter, pores about 2
in every mm. Some of the branches have annular constrictions,
giving them in places a slightly moniliform appearance ; terminations
of branches rounded. The tendency to ramify is not greatly deve-
loped in this form, although many of the stems have well-marked
branches exposed.

These specimens (like nearly all the Arctic fossils I have seen)
have long been exposed to atmospheric influence in the cliffs, and
consequently present a smoothed appearance.

Locality.—Beechey Island, brought home by Dr. A. Horner of the
8.Y. ‘“ Pandora.”

6. Atrypa phoca, Salter, sp. Pl. X. Fig. 8 (young state).

Rhynchonella phoca, Salter. Appendix to Sutherland’s Journal, 1850-51.
London, 1852, Geology by J. W. Salter, p. cexxvi. pl. v. figs. 1, 2, 3. Variety of
T. subcamelina, De Vern., Geol. Russ., vol. ii. pl. 9, fig. 4.

Atrypa phoca, Salter, sp. Haughton, Description of Fossils accompanying Capt.
Sir Leopold M‘Clintock’s Reminiscences of Arctic Ice-Travel in Search of Sir John
Franklin, Proc. Roy. Dublin Soc., 1856, vol. i. p. 240, pl. v. figs. 3, 4, 7.

Prof. Haughton, writing on this species (op. cit.), says :—‘ This is
the Rhynchonella phoca of Salter. I have ventured to place it under
the genus Atrypa, as I cannot find any trace of an aperture in or
under the beak.” I insert Mr. Salter’s description, altering only the
genus :—

“ Description.—Rounded, globose, valves longer than broad, their
greatest breadth at about the middle of the shell, thence becoming
rapidly narrower towards the front, which is somewhat truncated.
Valves equally convex in middle age; in old specimens the smaller
one rather gibbous near the beak, but not raised into a ridge. Beak
small but prominent, incurved in full-grown specimens. Front not
at all raised, but indented by a broad, shallow sinus. The large
valve has a distinct narrow median sulcus in the depression. Surface
concentrically striated, often interrupted by lines of growth.

‘Except for the imperforate beak, this might be taken for an Oolitic

390 Dr. James Croll—On Geological Time.

Terebratula. Itis so like the general shape of the species above
quoted, that I can hardly think it distinct ; however, the narrow
distinct sinus that runs down the larger valve appears constantly to
distinguish it from T. camelina. M. de Verneuil, who has seen our
specimens, pronounces the species distinct. T. prunum, of Dalman,
from Gothland, is nearly allied, but still quite another species.”

Localities.—Cape Riley, abundant. Cornwallis, Leopold, Griffith’s
and Seal Islands. This species is also most abundant on Beechey
Island.

Our figures on Plate X. are of immature specimens broken out of
amass of young Atrypa phoca, from Beechey Island, brought home
by Dr. A. Horner of the “ Pandora” (1875). We have since seen
and compared these with the large series in the Sutherland Collection,
Captain Penny, etc., and are satisfied from their gradations, that they
are all referable to the same species. Mr. Salter’s and Prof.
Haughton’s figures are of adult and aged specimens. We have
slabs from Beechey Island entirely made up of specimens of this
Brachiopod of all ages.

EXPLANATION OF PLATE X.
Fig. 1. Strephodes (Lonsdalia ?) Austini, Salter, U. Silurian or Devonian ? Beechey
Island, Lat. 74° 40’ N., Long. 92° W.
U. Silurian or Devonian ? Port Dundas, Lancaster Sound.
. Favosites polymorpha, Goldf. U. Silurian, Beechey Island.
Gothlandica, Linn. sp. U. Silurian, Beechey Island.
. Cyathophyllum Pickthornéi, Salter. U. Silurian, Beechey Island.
Salter. U. Silurian, Port Dundas.
. Alveolites arctica, H. Woodw. U. Silurian, Beechey Island.
. Atrypa phoca, Salter sp. (young state). U. Silurian, Beechey Island.
a. front view, 5. dorsal view, c. side view.

COMI > VB 09 1

II.—Caractysmic THrories or GEOLOGICAL Ciimate.!
By James Croxz, LL.D., F.R.S.,
of the Geological Survey of Scotland.

facie most important geological problem, and the one of all others

which at present excites the greatest attention, is the cause of
those extraordinary changes of climate which have taken place
during past ages. How are we to account for the cold and Arctic
condition of things which prevailed in temperate regions during
what is called the Glacial Epoch, or for the warm and temperate
climate enjoyed by the Arctic regions, probably up to the Pole,
during part of the Miocene and other periods? ‘Theories of the
cause of those changes, of the most diverse and opposite character,
have been keenly advocated, and one important result of the dis-
cussions which have recently taken place is the narrowing of the
field of inquiry and the bringing of the question within proper
limits.

At one time Lyell’s theory of the relative distribution of land
and water was generally regarded by geologists as sufficient. It is,
however, now generally admitted to be wholly insufficient to ex-
plain the now-known facts, and the conviction is becoming almost

1 Read before the Geological Society of London, May 8th, 1878.

Dr. James Croll—On Geological Time. 391

universal that we must refer the climatic changes in question to some
cosmical cause.

The theory of a change in the obliquity of the ecliptic has been
appealed to. This theory fora time met with a favourable reception,
but, as might have been expected, it was soon abandoned. ‘The re-
searches of Mr. Stockwell of America, and of Mr. George Darwin and
others in this country, have put it beyond doubt that no probable
amount of geographical revolution could ever have altered the obli-
quity to any sensible extent beyond its present narrow limits. It has
been demonstrated for example, by Mr. George Darwin, that supposing
the whole equatorial regions up to lat. 45° N. and §. were sea, and
the water to the depth of 2000 feet were placed on the Polar regions
in the form of ice—and this is the most favourable redistribution of
weight possible for producing a change of obliquity—it would not
shift the Arctic circle by so much as an inch!

Variations in the obliquity of the ecliptic having been given up as
hopeless, geologists and physicists are now inquiring whether the
true cause may not be found in a change in the position of the earth’s
axis of rotation. Fortunately this question has been taken up by
several able mathematicians, among whom are Sir William Thomson,'
Professor Haughton,? Mr. George Darwin,’ the Rev. J. F. Twisden,*
and others; and the result arrived at ought to convince every
geologist how hopeless it is to expect aid in this direction.

Mr. George Darwin has demonstrated that in order to displace
the pole merely 1° 46’ from its present position, 25 of the entire
surface of the globe would require to be elevated to a height of 10,000
feet, with a corresponding subsidence in another quadrant. There
probably never was an upheaval of such magnitude in the history of
our earth. And to produce a deflection of 3° 17 (a deflection which
would hardly sensibly affect climate) no less than 335 of the entire
surface would require to be elevated to that height. A continent ten
times the size of Europe elevated two miles would do little more
than bring London to the latitude of Edinburgh, or Edinburgh to
the latitude of London. He must be a sanguine geologist indeed
who can expect to account for the glaciation of this country, or for
the former absence of ice around the poles, by this means. We know
perfectly well that since the Glacial Epoch there have been no changes
in the physical geography of the earth, sufficient to deflect the pole
half-a-dozen miles, far less half-a-dozen degrees. It does not help
the matter much to assume a distortion of the whole solid mass
of the globe. ‘This, it is true, would give a few degrees additional
deflection of the Pole; but that such a distortion actually took place
is more opposed to geology and physics than even the elevation of a
continent ten times the size of Kurope to a height of two miles.

Mr. Twisden, in his valuable memoir referred to, has shown even
more convincingly how impossible it is to account for the great

1 British Association Report, 1876 (part 2), p. 11.
2 Proceedings of Royal Society, vol. xxvi. p. 41.

3 Transactions of Royal Society, vol. 167 (part 1).
4 Quart. Journ. Geol. Soc. February, 1878.

392 Dr. James Croll—On Geological Time.

changes of geological climate on the hypothesis of a change in the
axis of rotation. This conclusion has been further borne out by
another mathematician, the Rev. E. Hill, in an article in the June
Number of the Grotocican Magazine. And Professor Haughton,
in a paper read before the Royal Society, April 4th, and published in
Nature, July 4th, entitled, “A Geological Proof that the Changes
of Climate in Past Times were not due to Changes in the Position of
the Pole,” has proved from geological evidence that the Pole has
never shifted its position to any great extent. ‘If we examine,” he
says, ‘the localities of the fossil remains of the Arctic regions, and
consider carefully their relations to the position of the present North
Pole, we find that we can demonstrate that the Pole has not sensibly
changed its place during geological periods, and that the hypothesis
of a shifting pole (even if permitted by mechanical considerations)
is inadmissible to account for changes in geological climates.”

There is no geological evidence to show that, at least since Silurian
times, the Atlantic and Pacific were ever in their broad features
otherwise than they are now—two immense oceans separated by
the Eastern and Western continents—and there is not the shadow
of a reason to conclude that the poles have ever shifted much from
their present position. On this point I cannot do better than quote
the opinion recently expressed by Sir William Thomson :

“As to changes of the earth’s axis, I need not repeat the statement
of dynamical principles which I gave with experimental illustrations
to the Society three years ago; but may remind you of the chief
result, which is that, for steady rotation, the axis round which the
earth revolves must be a ‘principal axis of inertia,’ that is to say,
such an axis that the centrifugal forces called into play by the
rotation balance one another. The vast transpositions of matter at
the earth’s surface, or else distortions of the whole solid mass, which
must have taken place to alter the axis sufficiently to produce sensible
changes of the climate in any region, must be considered and shown
to be possible or probable before any hypothesis accounting for
changes of climate by alterations of the axis can be admitted. This
question has been exhaustively dealt with by Mr. George Darwin
in a paper recently communicated to the Royal Society of London,
and the requisitions of dynamical mathematics for an alteration of
even as much as two or three degrees in the earth’s axis in what may
be practically called geological time shown to be on purely geological
grounds exceedingly improbable. But even suppose such a change
as would bring ten or twenty degrees of more indulgent sky to the
American Arctic Archipelago; it would bring Nova Zembla and
Siberia by so much nearer to the pole: and it seems that there is
probably as much need of ECegumlny for a warm climate on one side
as on the other side of the pole. There is in fact no evidence in
geological climate throughout those parts of the world which geo-
logical investigation has reached, to give any indication of the poles
having been anywhere but where they are at any period of geological
time.” ?

1 This has been proved to be the case by Prof. Haughton, Nature, July 4, 1878.
2 Trans, of Geol. Soc. of Glasgow, Feb. 22, 1877.

Dr. James Croll—On Geological Time. — 593

Tn the memoir from which the preceding paragraph is quoted, Sir
William maintains that an increase in the amount of heat conveyed
by ocean currents to the Arctic regions, combined with the efiect of
Clouds, Wind, and Aqueous Vapour, is perfectly sufficient to account
for the warm and temperate condition of climate which is known to
have prevailed in those regions during the Miocene and other periods.

Now this is the very point for which I have been contending for
upwards of a dozen years. The only essential difference between
Sir William’s views and mine is simply this: he accounts for an
increase in the flow of warm water to the Arctic regions by a
submergence of the cireumpolar land, whereas I attribute it to certain
agencies brought into operation by an increase in the excentricity of
the earth’s orbit. Such geological evidence as we possess of warm
episodes in the polar regions does not point to such high temperatures
being specially due to submergence of the polar land. For taking the:
Miocene epoch as an example, all the way from Ireland and the
Western Isles, by the Faroes, Iceland, Franz-Joseph Land, to North
Greenland, the Miocene vegetation and the denuded fragmentary
state of the strata point to a much wider distribution of polar land
than that which now obtains in those regions. What has chiefly
tended to retard the acceptance of the theory of secular changes of
climate discussed in my work entitled ‘Climate and Time,” is the
fact that physicists have not fully realized to what an immense
extent the climatic condition of our globe is dependent upon the
distribution of heat by means of ocean currents. Were it not for
the enormous amount of heat transferred from equatorial to temperate
and polar regions by means of ocean currents, the globe would
scarcely be habitable by the present orders of sentient beings. When
this fact becomes fully recognized, all difficulties felt in accounting
for geological climate will soon disappear. The climatic influence
of ocean currents has not been sufficiently considered, owing doubt-
less to the fact that before I attempted to compute the absolute
amount of heat conveyed by the Gulf Stream, so as to compare it
with the amount directly received by the Atlantic from the sun, no
one had ever imagined that that ocean in temperate and Arctic
regions was dependent to such an extent on heat brought from the
Equator! And this being so, it was impossible for any one fully to
realize to what an extent climate must necessarily be affected by an
increase or a decrease of that stream.

Sir William Thomson speaks of his theory being that of Lyell ;
but beyond the mere assumption of the submergence of the circum-
polar land the two theories have little in common. Indeed, no one
who believes (as Sir William does) that the former warm climatic
condition of the polar area was mainly due to a transference of heat
from equatorial to Arctic regions by means of ocean currents can
logically adopt Lyell’s theory. According to that eminent geologist,
the temperature of the Arctic regions was raised by the removal of
the continents from polar and temperate regions to a position along

1 Capt. Maury, of the U.S. Navy, was the first to call attention to the influence of

the Gulf Stream on climate. Physical Geography of the Sea, 8th edition, 1860,
p. 23.—Enir. Gzou. Mac.

394 ' Dr. James Croll—On Geological Time.

the equator. But if the equatorial regions were occupied by land
instead of water, the possibility of conveying heat to temperate and
arctic regions by means of ocean currents was completely cut off.
In fact, one of the most effectual ways of lowering the mean tempera-
ture of the globe would be to group the continents along the equator.

The surface of the ground at the equator becomes intensely heated
by the solar rays, and this heat is radiated into space much more
rapidly than it would from a surface of water warmed under the
same conditions. Again, the air in contact with the hot ground
becomes more speedily heated than it would if it were in contact
with water, and consequently the ascending current of air over the
equatorial lands carries off a greater amount of heat than it could
have done from a water-surface. Now, were the heat thus carried
off to be transferred by means of the upper currents to high latitudes,
‘and there employed in heating the earth, then it might to a consider-
able degree compensate for the absence of warm ocean currents. In
such a case land at the equator might be nearly as well adapted as
water for raising the temperature of the whole earth. We know
very well, however, that the heat carried up by the ascending
current at the equator performs little work of this kind, but on the
contrary is almost wholly dissipated into the cold stellar space above.
Thus instead of warming the globe, this ascending current is in
reality a most effectual means of getting rid of the heat received
from the sun, and thereby reducing the temperature. Since then the
earth loses as well as gains the greater part of her heat in equatorial
regions ; it is there that the substance best adapted for preventing
the dissipation of that heat must be distributed in order to raise
the general temperature. Now, of all substances in nature water
seems to possess this quality in the highest degree; and being a
fluid it is adapted by means of currents to carry the heat which it
receives to every region of the globe.

It has been urged as an objection to any ocean-current theory that
while it provides the requisite amount of heat, it fails to remove the
three or four months’ darkness of an Arctic winter, which must have
proved fatal to plants of the Miocene period. This objection seems,
however, to have no foundation in fact. Sir Joseph Hooker stated
to the Royal Society at the close of the reading of Mr. George
Darwin’s paper that palms and other plants brought from the tropics
survived the winter in St. Petersburg without damage, though
matted down in absolute darkness for more than six months. And
he was of opinion that the want of sunlight during the Arctic winter
would not be very prejudicial to the plants.

But a cause must be found as well for the cold of the Glacial Epoch
as for the warm climate of the Arctic regions that obtained in Miocene
times. According to Lyell the continents would require to be
moved to high temperate and polar regions to bring about a
glacial condition of things in Britain. But this is an assumption
which the present state of geological science will hardly admit. It
is perfectly certain that there have been no such vast revolutions
in physical geography in post-Tertiary times.

Dr. James Croll—On Geological Time. 395

According to others, elevation of the land in the regions glaciated
is assigned as the cause of that glaciation, and if the ice had been
merely local, such an explanation might have sufficed. But we know
the whole Northern Hemisphere down to tolerably low latitudes has
been subjected in post-Tertiary times to the rigour of an Arctic climate ;
so that according to this theory we must assume an upheaval of the
entire hemisphere—an assumption too monstrous to be admitted and
as useless as absurd.

Tendency in Geology to Cataclysmic Theories—There has always
been in Geology a tendency to cataclysmic theories of causation; a
proneness to attribute the grand changes experienced by the earth’s
crust to extraordinary causes. Geologists have only slowly become
convinced that those changes were the effects of the ordinary agencies
in daily operation around us. For example, hills were formerly
supposed to be due to sudden eruptions. and upheavals; valleys to
subsidences, and deep river gorges to violent dislocations of the earth.
All this is now changed, and geologists in general have become con-
vinced that the main features of the earth’s surface owe their exist-
ence to the silent, gentle, and continuous working of such influences
as rain and rivers, heat and cold, frost and snow.

It is not difficult to understand why a belief in cataclysms should
so long have prevailed, and geologists should have been so prone to
assume the existence of extraordinary causes acting with great force.
Geological phenomena come directly under the eye in all their
magnitude, and consequently produce a powerful impression on the
mind. The quiet and gentle operations of nature’s ordinary agencies
appear utterly inadequate to produce results so stupendous ; and one
naturally refers effects so striking to extraordinary causes. Beholding
in a moment the effect, we forget that the cause has been in operation
for countless ages.

We look for example at a gorge, perhaps a thousand feet in depth,
with a small streamlet running along its bottom. Our first im-
pression is that this enormous chasm has been formed by some
earthquake or other convulsion of nature rending the rocks asunder.
And it is only when we examine the chasm more minutely, and find
that it has been actually excavated out of the solid rock, that we
begin to see that the work has been done by running water. At
first, however, we do not imagine that such a chasm can have been
made by the streamlet in its present puny form. We conclude that
in former ages a great river ran down the channel. We fail to give
the element of time due influence in our speculations. We overlook
the fact that the streamlet has been deepening its bed for perhaps
millions of years. Why, London itself might have been built by
one man had he been at work during all the time that the streamlet
was cutting out its gorge! When such considerations cross the
mind, every difficulty vanishes, and we feel satisfied that all the
work has been performed by the streamlet.

The very same may be said in regard to the origin of hills, valleys,
and other features of the earth’s surface. Yet how difficult it is still
to convince some geologists that. our mountains have been formed,

396 Dr. James Croli—On Geological Time.

as a rule, not by eruptions and upheavals, but by the slow process
of subaerial denudation.

Cataclysmic explanations of phenomena have to a large extent
disappeared from the field of physical geology. But there is one
department in which they still monopolize the field; viz. in that
which treats of great climatic changes in former ages. Just as in
physical geology great and imposing effects have been attributed to
extraordinary causes, so in questions of geological climate vast vicissi-
tudes have been referred to equally vast and unusual agencies.

We know that at a period comparatively recent almost the entire
Northern hemisphere down to tolerably low latitudes was buried
under snow and ice, the climate being perhaps as rigorous as that of
Greenland at the present day. And we know further that at other
periods, Greenland and the Arctic regions were not only to a large
extent at least free from ice, but also enjoyed a climate as warm and
genial as that of England. To attribute results so striking and
stupendous to such commonplace agencies as ocean currents, winds,
clouds, and aqueous vapour is at present considered to be little else
than absurd. Extraordinary and imposing causes proportionate to
the effects are therefore sought.

To account for the Glacial Epoch, for example, the land was at one
time supposed to have stood much higher than at present. It was
soon discovered, however, that the glaciation was much too general
to be explained by such means. Others believed that it might be
accounted for by assuming a displacement of the continents, but this
hypothesis had likewise to be abandoned when it became known that
no alteration in the position of our continents and ocean basins has
taken place since the Glacial Epoch.

Others again imagined that some great change had probably taken
place in the obliquity of the ecliptic so as to bring the Arctic circle
down to beyond the latitude of England. And in order to bring
this about what enormous upheavals were supposed to have oc-
curred! It wassoon, however, shown that no possible rearrangement
of matter on our globe could materially affect the obliquity; and
besides this, it was further pointed out that even supposing the
Arctic circle was by such means to be shifted down to our latitude,
yet it would not bring an Arctic climate along with it but the reverse.
This hypothesis being in its turn abandoned, it was next assumed
that the earth’s axis of rotation must have been moved so as to carry
our island up to the Arctic regions. But to shift the axis of rotation
even so much as 3°, upheavals and subsidences of a magnitude
hitherto unheard of in geological speculations had to be assumed.
A change of 3°, however, being totally inadequate to account for the
great changes of climate in question, earthquakes of sufficient power
to break up the solid framework of the globe had to be called into
operation, so as to cause a rearrangement of matter sufficient to
produce a displacement of the pole to the extent required. The
amount of distortion necessitated by this theory is so enormous that
most of its advocates have recently abandoned it as hopeless.

But is there really after all any necessity for invoking the aid of

Dr. James Croli—On Geological Time. , 397

agencies so extraordinary and gigantic? To carve a country, say like
Scotland, out of hard Silurian rock into hill and dale and mountain
ridges, thousands of feet in height, is certainly a more stupendous
undertaking than simply to cover the same area with a sheet of ice.
And if commonplace agencies like rain and rivers, frost and snow,
can do the former, why may not such agencies as ocean currents,
winds, clouds, and aqueous vapour, be sufficient for the latter ?

That geological climate should depend on the causes to which we
refer cannot appear more improbable to the geologists of the present
day than the inference that hills and valleys were formed by atmo-
spheric agencies did to the geologists of the last generation. And
there is little doubt that by the next generation the one conclusion
will be as freely admitted as the other.

When a physicist so eminent as Sir William Thomson expresses
his decided opinion that the agencies in question are all that are
necessary to remove the ice from the Arctic regions, and confer on
them a mild and temperate climate, it is to be hoped that the day is
not far distant when the climate controversy will be concluded.
When the fact comes to be generally admitted by physicists that a
great increase in the temperature and volume of the ocean currents
flowing polewards is sufficient to prevent the accumulation of ice in
the Arctic regions, it will then be allowed that we only require a
great decrease in the volume and temperature of the currents in order
to account for the former accumulations of ice on the temperate
regions, or, in other words, to explain the occurrence of the Glacial
Epoch. And when this position is reached, it will be seen that the
whole depends upon a very simple cause, requiring neither the sub-
mergence nor the elevation of continents, nor any other great change
in the physical geography of the globe.

When the excentricity of the earth’s orbit is at a high value and
the Northern winter solstice is in perihelion, agencies are brought into
operation which make the 8.H. trade winds stronger than the N.E., and
compel them to blow over upon the Northern hemisphere as far
probably as the Tropic of Cancer. The result is that all the great
equatorial currents of the ocean are impelled into the Northern
hemisphere, which thus, in consequence of the immense accumulation
of warm water, has its temperature raised, and snow and ice to a
great extent must then disappear from the Arctic regions. When the
precession of the equinoxes brings round the winter solstice to
aphelion, the condition of things on the two hemispheres is reversed,
and the N.E. trades then blow over upon the southern hemisphere,
carrying the great equatorial currents along with them. The warm
water being thus wholly withdrawn from the Northern hemisphere,
its temperature sinks enormously, and snow and ice begin to ac-
cumulate in temperate regions. The amount of precipitation in the
form of snow in temperate regions is at the same time enormously
increased by the excess of the evaporation in low latitudes resulting
from the nearness of the sun in perihelion during summer.

The final result to which we are, therefore, led, is, that those warm
and cold periods, which have alternately prevailed during past ages,

398 G. H. Kinahan—Irish Silurian Land Plants.

aré simply the great secular summers and winters of our globe,
depending as truly as the annual ones do upon planetary motions,
and like them also fulfilling some important ends in the economy of
Nature.

IIJ.—Lanp Puants 1n THE IrR1sH SILURIANS.
By G. H. Kryanan, M.R.I.A.

HE land-plants lately discovered both in'the American and
Continental Silurians seem to be attracting attention, while
those found in Ireland nearly a quarter of a century ago appear to be
quite forgotten. This is probably due to the unsatisfactory condition
in which the classification of the Irish Silurians are left at the
present time; perhaps therefore it is allowable for me to give a
short description of these rocks.

There are considerable areas in different parts of Ireland in which
the rocks are apparently of about similar age; the larger of these
being: Ist, a tract in the Dingle Promontory, county Kerry (Dingle
beds); 2nd, a very extensive area in South-west Cork (Glengariff
grits); 3rd, a tract South-west of Clew Bay, county Mayo (Louisburgh
group); 4th, an area east and north-east of Clew Bay (Croaghmoyle
conglomerates) ; 5th, a long narrow tract in the Curlew Mountains,
counties of Sligo and Roscommon (Lough Gara beds); 6th, an ex-
tensive area in the counties of Fermanagh and Tyrone (Fintona and
Slievemore group); but besides these there are some small patches.
In these rocks good fossils are not recorded ; excepting the Glengariff
grits, which contain tracks probably Crustacean at the Light House,
Valencia Island ; fucoids (?), on the shore of Valencia River; plants
(?) on the south side of Beginish and on the sea-shore near Puffin
Island; on the west side of Coomasaharn Lake, south-east of Kells,
plant-stems, some of them an inch and a half in diameter, and
irregularly ribbed in a longitudinal direction; and in the Glengariff
grits, south and south-west of Killarney, imperfect plants were
observed in many places, the most perfect occurring in the Owen-
reagh valley north of Windy Gap.

In the later editions of Griffith’s map the Dingle, Glengariff, and
Louisburgh rocks were classed as Silurians, while the others pro-
visionally were placed as Old Red Sandstone, because, as stated by
that eminent geologist, he never had time to properly examine them.
During the progress of H.M. Geological Survey it was found that the
Glengariff grits were conformable with the overlying Carboniferous
rocks in the county of Cork; while in the year 1854, low down near
the bottom of the Glengariff grits, Du Noyer found plants, and in the
following year I also found them ;' these plants were supposed by
the late Mr. J. W. Salter to be of Carboniferous types. In 1856,
Du Noyer, in the Dingle Promontory, found that similar rocks to
the Glengariff grits (as had been previously known to Griffith) lay
conformably on rocks containing typical Silurian fossils, while they
were overlaid unconformably by about 5000 feet in thickness of Old
Red Sandstone (Lower Carboniferous Sandstone). In the autumn
of the same year these rocks were visited by Griffith, Murchison, .

G. H. Kinahan—TLvish Silurian Land Plants. 399

Salter, and Jukes. The first two were inclined to place the Dingle
and Glengariff rocks among the Silurians, while the other two
objected on account of the fossils,—eventually it was arranged that
they were to be joined provisionally to the Old Red Sandstone
under the names of Dingle beds and Glengariff grits, until the
somewhat similar rocks in Connaught and Ulster were examined.
Afterwards, Jukes, although he did not separate the Glengariff
grits from the Old Red Sandstone, gave the Dingle beds a distinct
grouping; but Du Noyer, and all the other officers who were en-
gaged in the examination of the country, considered that the Dingle
beds and Glengariff grits were of one age. During Jukes’s life-
time, these rocks were being gradually worked out; but after his
death seemingly they have been forgotten.

The Louisburgh beds, although no fossils have been found in them,
except some Annelid burrows and obscure markings, are in part
similar to the fossiliferous Salrock beds, and in part like the fossil-
iferous Mweelrea beds; they probably are the newest group of the
Silurians in Mayo. The Croaghmoyle conglomerates seem to be
capped unconformably by Carboniferous rocks; they are like the
Toormakeedy conglomerates, associated with which Upper Llan-
dovery fossils occur; also the limestones that occur in the Toor-
makeedy rocks seem to occur in places at the margin of Croaghmoyle
conglomerates. In red beds associated with the Croaghmoyle
conglomerates I detected obscure markings that possibly might be
fucoids, but they were so very indistinct that no reliance could be
placed on them.

The Lough Gara rocks were suspected by Griffith to be simi-
larly placed to the rocks at Dingle; that is, to lie conformably on
the Silurians, while they were capped unconformably by Old Red
Sandstone (Lower Carboniferous Sandstone). When I visited
them with Foote, that observer seemed inclined to class them with
the Dingle beds, but unfortunately he did not live to complete
his examination. In the Government Survey Memoirs, Ex. Sheet
76, page 7, Berdoc Wilkin says of these rocks near Ballyhaderreen,
“They appear to be conformable with the Silurian beds, but are
overlapped unconformably ..... by the Lower Carboniferous
Sandstones”; this observer coming to the same conclusion as that
suggested by Griffith and Foote. Foote suspected that fossil plants
occurred in these rocks.

The Fintona and Slievemore rocks are very similar to those in the
Curlew Mountains, and are capped unconformably by the Old Red
Sandstone (Lower Carboniferous Sandstone). Portlock states that
they seem to pass conformably into the underlying Cambro-Silurian
rocks, which would make them of great age; but Griffith suggested
that they were of the same age as the Dingle beds. The Dingle,
the Mweelrea, the Toormakeedy, the Curlew Mountain, and the
Fintona rocks have conditions in common: all are unconformable
with the overlying Lower Carboniferous Sandstone (Old Red Sand-
stone) ; all have similarly associated basic felstones (Eurytes) and
tuffs; and all, except the Fintona rocks, lie conformably on rocks
containing typical Silurian fossils.

400 A. F. Griffith—Find of a Flint Implement in Gravel.

It may be mentioned that although attempts have been made
to classify the Irish Silurians similarly to those of England, yet
it is not a satisfactory classification, as the fossils of the English
groups are mixed up together in the Irish ones; this is a subject
which if fully entered into would take up too much space, but it may
be mentioned that in the Kerry, Galway, and Mayo Silurians there
is a thin zone, at about the same geological horizon, which carries
Cambro-Silurian (Caradoc) fossils, while in the rocks below and
above they are of Upper Llandovery and Wenlock types. In one
portion of Galway there are at least 3000 feet in thickness of Upper
Llandovery rocks below this zone. JI would suggest that the
American and Continental Silurians in which Land Plants occur
are possibly equivalents of the Irish groups to which I now draw
attention.

Norz.—Prof. Claypole has described a Lepidodendroid plant, Glyptodendron
Eatonense, from the Upper Silurian (Clinton) rocks of Ohio, in the American Journal
of Science for April, 1878, p. 302.—J. M.

TV.—On a Fuint ImpeLement rrom tan BARNWELL GRAVEL.
By A. F. Grirritu, Esq.

FEW weeks ago a flint implement was found in the gravel-pit

at Barnwell, near Cambridge, by the workmen, from whom

I bought it. It is a very fine specimen of the hache type,

its greatest length being 6#ins., its greatest breadth 33 ins., and

thickness 24. It corresponds closely with specimens in the Wood-

wardian Museum, from Thetford, in Suffolk, and from Amiens. It

agrees almost exactly in size and outline with an implement of the

«‘ River-drift type,” figured by Dr. John Evans in his beautiful work

on the “‘ Ancient Stone Implements of Great Britain”; from Bidden-

ham, Bedford (fig. 414, p. 481); also with one from’ Redhill,
Thetford (fig. 427, 4 nat. size, p. 496, op. cit.).

The pit where it was found is in the well-known Barnwell river
gravel, which contains a considerable number of bones of Mammalia,
including those of Bos, Equus, Cervus, Rhinoceros tichorhinus,
Elephas primigenius and antiquus, and Hippopotamus,’ and has in
places a thin band of shells, amongst which Unio littoralis and Cyrena
fluminalis are common. This band, however, is not found in the
present pit, though it occurred in the old pit about 3850 yards
distant, on the side of the Newmarket Road, which was in the same
gravel, and is on the same level as the present one. The occurrence
of a worked flint associated with these shells is, I believe, very
unusual. At Menchecourt, in France, Cyrena fluminalis was found
by Prof. Prestwich, in the implement-bearing gravel, while I only
know of one instance having been recorded of a worked flint having
been found associated with Unio littoralis; this was found in the
brick-earth of Crayford, Kent, by Mr. Fisher, in 1872.’

The only other evidence of man’s existence which has hitherto
been obtained from this deposit is perhaps of a rather doubtful

1 Quart. Journ. Geol. Soc., vol. xxii. p. 476.
2 Grou. Maa. June, 1872.

A. F. Griffith—Find of a Flint Implement in Gravel. 401

character, consisting of a bone supposed to have been cut by man
before its burial in the gravel. This was described by Prof. H. G.
Seely, in his paper on the Fen Drifts.

A few worked flints have been found round Cambridge, in gravel
heaps by the road-side. Some specimens, now in the Woodwardian
Museum, were found by Prof. Hughes, in gravel which came from
the Observatory Hill. Mr. Fisher also has a small hache of much the
same type as the Barnwell one, but much smaller, and more oval,
being only 34 inches long ; this he found in gravel which came from
the Chesterton pits. Both this and the Observatory specimens are
much more water-worn than that from Barnwell. The implements
found at both these localities are of the regular “ River-drift period ”
type, closely resembling several of the woodcuts in Dr. John Evans’s
«« Ancient Stone Implements of Great Britain,” e.g., Implement from
Santon Downham, fig. 486, p. 504; from Shrub Hill, Feltwell,
fig. 448, p. 515; from Hoxne, Suffolk, fig. 449, p. 519; from
Fordingbridge, Ashford, on the Wiltshire Avon, fig. 478, p. 559;
also one from Wookey Hyena-den, fig. 413, p. 473. I have also a
well-marked chip, found in gravel in a little pit close to the railway
on the south side, about one mile from Lord’s Bridge Station, in the
direction of Old North Road.

The section of the pit at the corner where my specimen was
found is roughly as follows :—

IMO UTA CEE SOLU yh cee agente alee ci een eae feces 3 feet.
Aor ral, wicked Wee cilia e! Gee en CRUE ae Ree 1 to 2 feet.
ii. Irregular gravel, with band of sand wu. wu 3 to 2 feet.
iv. Level-bedded gravel with marly bands ....._..... 9 feet.

The implement was found near the top of the bed iv. The band
with shells occurred near its base.

With regard to the authenticity of the specimen, I may say that
when I got it, it had been partially cleaned, but all the corners were
still full of the peculiar fine white gravel of the bed. I only gave
one shilling for it, which goes to prove that the men found it on the
spot, and did not buy it in the town to sell it at a high profit in the pit.

A remarkable character of the weapon is, that while on one side
and at the blunt end it is of the yellowish colour so common in
Paleolithic flints from gravel, its other side is much whitened, pro-
bably by the action of the infiltrated water which is highly charged
with lime. At the suggestion of Prof. T. G. Bonney, I tried to find
similar specimens among the rough unworked flints in the pit. In
this I was only partially successful, as I could find none with the
difference of colour on the two sides so marked; but this was, I
believe, due to the fact that there are very few flints of any con-
siderable size in the lower part of the deposit.

In the subjoined woodcut (p. 402) is given a section from the
Observatory gravel-pit to that at Barnwell. The heights given are
measured from the level of the river Cam below the Jesus College
locks; the section cuts the river just above them ; the direction of the
section runs 114°S. of West and N. of East. The base of the gravel

1 Quart. Journ. Geol. Soc., vol. xxii. p. 477.
DECADE II.—VOL, V.—NO. IX, 26

A. F. Griffith—Find of a Flint Implement in Gravel.

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Rk. Damon—* The Great Northern Drift.” 403

on the Observatory Hill is about 56 feet above the present river level.
The Castle Hill, which is partly natural, partly artificial, has at its
base another bed, whose level I was unable to ascertain accurately ;
this probably belongs to the Chesterton gravel. Jesus College stands
on gravel at a lower level still, while the base of the Barnwell bed
is at a height of sixteen feet above the river level. Thus we have
four distinct terraces, unless the Jesus College bed forms part of the
Chesterton series, which is improbable.

I must express my thanks to Mr. O. Fisher, M.A., and Prof.
Hughes, for the encouragement and help they have given me in the
preparation of this brief notice. My thanks are also due to Mr.
Haddon, of Christ’s College, for his kindness in making drawings of
the implements for me.*

Curist’s CottEcE, June, 1878. A. F. GRirFita.

V.—WaysipE Notes in TRAVELS oveER Hurors.—TuHE Great
NortrHern Drirt.

By Rozert Damon, F.G.S.

HE overland route to Russia via Konigsberg or Warsaw—now
accomplished with comparative ease—reveals some instructive
facts connected with one of the most recent yet extreme of
climatal changes which has contributed to mould and fashion so
large a portion of the surface geology of Northern Europe. I refer
to the ‘“‘Great Ice Age,” or “Glacial Period,” when a frozen sea
probably covered the extensive plains now known as Russian Poland.
Soon after leaving the German frontier, granitie débris and small
stones everywhere appear on the surface. These granitic erratic
boulders, for such they really are, increase in number and dimen-
sions as the journey is pursued, so that in a few hours they have so
augmented that a considerable distance might be traversed by stepping
from one of these stones to another. Now and then there are some
one or more of exceptionally large proportions, but taken as a whole,
the increase in size is extremely uniform, and before the environs of
St. Petersburg or Moscow is reached, many of them attain colossal
dimensions. Having in my recollection the block of granite in the
Admiralty Square in St. Petersburg, on which stands the equestrian
statue of the Czar Peter, many of the boulders referred to are
hundreds of tons each in weight. In some instances the railway
has paid respect to their dimensions and avoided them, for no
ordinary mechanical power could effect their removal. As may be
expected, their size increases as their source is approached, though on
sea-beaches the larger pebbles are carried the furthest because they
are said to offer a larger surface for the moving force to act upon.

It requires but little penetration to discern that the direction of
the transporting power by which this vast mass of erratics has heen
sown broadcast over the central plain of Europe, has acted from N.
or N. E. to 8S. and 8. W. Several specimens of granite gneiss, etc., I

! These are not reproduced here, it being believed sufficient to refer the reader to
Dr. John Evyans’s work.—Epitr. Grou. Mac.

404 R. Damon—“ The Great Northern Drift.”

was able to identify as having been derived from the granitic region
of Finland, nearly 1000 miles distant, while others have been traced
to the rocks which surround the shores of Lake Ladoga, imme-
diately north of St. Petersburg.

The amount of material transported is not to be judged merely
from what appears on the surface. When a space has been opened
and the soil removed, Boulders are exposed piled one upon the
other in heaps to an enormous depth, recalling to one’s mind the
accumulated masses of rocks on the shore of a lofty line of coast.
These quarries in the Boulder formation being, humanly speaking,
inexhaustible, will ever be a source of valuable building material to
a district where no other stone besides can be obtained ; and when
it is further considered that this represents an area of probably
1000 miles in one direction, we realize in part the potency of this
most ancient but, comparatively speaking, recently recognized of
geological agencies Ice—either as Coast-ice, Pack-ice, Glaciers, or
Icebergs.

Tn the district around Konigsberg other boulders abound from a
different region, viz. the Silurian rocks of Sweden. ‘These are so
numerous that in the University Museum of that city a really fine
collection of Silurian fossils has been formed, derived exclusively
from boulders transported over the Baltic. As the cold of the
Glacial Period gave way to a more genial climate, the waters formed
for themselves outlets to the Baltic in the rivers Vistula, Niemen,
Dwina, etc., thus creating so many highways extending far into the
interior of the vast corn-growing plains of Russian Poland. Here
during the winter and spring barges of enormous dimensions are
constructed on the ice ready to float down the stream at the return of
summer, laden with wheat, to stock the granaries of their respective
ports of Dantzic, Konigsberg, ete., from whence Hurope draws much
of her supplies of grain.

This enormous tract consists of almost unbroken alluvial plains, as
boundless as the ocean, without a tunnel, a cutting or a bridge being
visible through an entire day’s journey. The railroad is so straight
and the scenery so monotonous, that the traveller can hardly realize
his onward progress; the track seems ever to converge towards the
same vanishing points on the horizon both in front and behind.
Having taken this route many years since, and before the completion
of the railway into Russia, 1 observed how the country on each side
of the line of rails has been cleared, and the granite blocks utilised
for building purposes, road-metal, ete.

In the Northern Cemeteries the boulders are also frequently used
as tomb-stones; those being selected that have a wide base; but no
tool is applied to them save for the inscription, which is as simple as
the monolith itself. For example:

“* Admiral Schonbein.
1824 — 1875.”

The journey derives additional interest from historic associations,
as it was at Kowno, the frontier station, that the French army, con-
sisting of 453,000 men, on the 24th and 25th June, 1812, crossed

Notices of Memoirs—Vanden Broeck’s Geology of Antwerp. 405

the Niemen; and at Wilna, the station following, where, on De-
cember 13th, six months after, Napoleon united his retreating force,
reduced to less than 25,000 men, —the Russians, desertions and the
cold disposing of the remainder.

After describing the terrible passage of the Beresina, Labaume,
one of Napoleon’s staff, writes:—‘ Arrived at the opposite bank,
like ghosts returned from the infernal regions, we fearfully looked
behind us, and beheld with horror the savage countries where we
had suffered so much.”

INTO RICANS O)SE | AME AM AO nrieyS-

SKETCH OF THE GEOLOGY AND PaLmoNnTOLOGY oF THE PLIOCENE
Beps or tae Antwerp District. By H. Vanpen Brorcx.
Fase. II. (Brussels, 1878.)

HE first fascicule of this work was published in 1876 and noticed

in the GronocicaL Macazine for July, 1877. With the fascicule
now issued, it forms a stratigraphical introduction to MM. Vanden

Broeck and Miller’s Foraminifera of the Belgian Pliocene, being

Part I. of that work.

The first fascicule dealt with the Lower Sands of Antwerp, the
second takes up the Middle and Upper Sands of the same district,
concluding with a general résumé of the entire work, a table of
stratigraphical equivalence, here reproduced, a list of works on the
subject, further data and corrections, and a topographical chapter
explanatory of the map (not geological) of the area under discussion.

The Middle Sands have been designated as follows :

Scaldesian (in part) 600 bod nee bse Dumont, 1849.
Grey or Middle Crag ser es aed ace Lyell, 1852.
Grey Sands (in part) bes 566 Nyst, 1861.
Isocardia cor Sands and Bryozoan Rock ... Nae Cogels, 1874.

They consist generally of fine sand, more or less clayey, and very
rarely coarse or pebbly: the glauconite grains in them are less
abundant and smaller than in the Lower Sands. They have been
divided into Grey and Yellow Sands, and correlated with the White
and Red Crags of England respectively on the strength of this
difference in colour. The fallacy of applying such a test is abun-
dantly shown by the author, whose remarks on this important subject
may be summed up as follows :—

Percolating water charged with carbonic acid and oxygen acts
on both glauconite and carbonate of lime. Where percolation is
rapid, it oxidises the glauconite; where slow, it dissolves away the
fossils. Thus the surface of any glauconitic or shelly deposit.
whether exposed directly or covered by permeable beds, is deprived
of fossils and oxidised to a greater or less extent, the capricious

1 Les Foraminiféres des Couches Pliocénes de la Belgique. Par E. Vanden
Broeck et H. Miller. re partie: Esquisse Géologique et Paléontologique des
Depots Pliocenes des Environs d’Anvers. Par Ernest Vanden Broeck. Extrait

des Annales de la Société Malacologique de Belgique, tome ix. pp. 83-379 [both
fascicules], pl. iv.

406 Notices of Memoirs—Vanden Broeck’s Geology of Antuerp.

percolation of water giving rise to great irregularity of alteration, and
producing the appearance, often strongly marked, of unconformity.
To separate such deposits by their colour, therefore, is to mass all
altered beds as of one age, all unaltered as of another, leading of
course to hopeless confusion in lists of fossils based on this division,
and this confusion has been increased by the inclusion of specimens
from post-Tertiary deposits of similar lithological character. All lists
hitherto published are therefore to a large extent worthless, with the
exception of those recently compiled by M. Cogels.

The Middle Sands are rather Diestian than Scaldesian in their
faunal affinities, and slightly anterior to the Coralline Crag, to which
they are closely allied. By the northward and westward movement
of the area of deposition, due to the elevation of Belgium and
simultaneous depression of Holland and East Anglia, the Coralline
Crag was still in process of deposition when the Belgian area
emerged.

The Middle Sands have two facies, one of comparatively shallow
water, distinguished by the predominance of Isocardia cor, the other
of deeper water, notable for its prefusion of Bryozoa. Enormous
quantities of Cetacean bones, often as entire skeletons and connected
vertebral columns, occur throughout the series, but the Ziphioids
and Delphinide of the Lower Sands are here replaced by Mysticeti
and Phocids. The fish are mostly Selachians, some of them of
enormous bulk.!

Like the Coralline Crag, the Middle Sands have suffered great
denudation previous to the deposition of the Upper Sands (=Red
Crag).

Remarks on the horizon of certain local deposits and of Terebratula
grandis (a Middle Sands species referred by M. Cogels, from deficient
evidence, to the Lower Sands) are followed by a sketch of the
geography of the Middle Sand period. The Belgian basin extended
from Cotentin to Denmark and Iceland: the Mediterranean had
nearly its present outline, whilst in Austria and South Russia occur
isolated marine deposits of this age.

Passing to the Upper Sands we find a number of synonyms of
which but one need be named, Sables @ Trophon antiquum, given by
M. Cogels in 1874.

The Upper Sands are of littoral origin, coarse and pebbly, rarely
more than 14 feet thick, grey where protected by overlying im-
permeable beds from percolating water, but mostly oxidised. Their
derived fossils being clearly distinguishable from contemporaneous
species, these Antwerp beds may help to settle the vexed question of
“derivation”? in the English Red Crag, as many species from the
latter, supposed to be derived, are found in the Upper Sands.

As with the previous series, the Upper Sands are slightly anterior
to the Red Crag, except perhaps the Crag of Walton-on-the-Naze,
which has an earlier facies than the rest of the Red Crag, and may be
synchronous with the Upper Sands. The base of both contains

' Carcharodon megalodon was 70 feet long, and its jaws were 14 feet in circum-
ference.

SYNOPTICAL AND CHRONOLOGICAL TABLE OF THE PLIOCENE AND QUATERNARY Bzrps
OF THE ANTWERP Basin.

Coast | DEEPe-WATER
GEoLoGIcaAL PERIODS Dunes & Ratsep LITTORAL AND AND SHALLOW DEposITs
AND PHASES, BEACHES. Bracu DeEpostts. WatTER DISTANT FROM
| DEposItTs. THE Coast.
Stratified Clays and
Blown Sands. | Sands of the Lower
¢ Campinien. Upper Campinien of Kiel,
QUATER- | Campinien. | etc.
NARY. < (6 Beds with casts and
| | fragments of Plio-
L Diluvium. A cene shellsand bones
f \ of the Mammoth and
| | Rhinoceros.
L Drift with Flints.
Total emergence of the Pliocene Basin of Antwerp.
Last phase of the Pliocene period
represented by deposits not known
in the Antwerp basin.
| Shell-beds of Ranst
and of the district
to the East.
Upper
Sands of < ‘
Antwerp. a tenlaeeous
. __ | Sandsof Calloo with | 8224s of Wyne-
: ghem with
Trophon antiquum. Trophon
| antiquum.
Bed with débris and casts of shells;
IGS EES Sy first deposit of sands with Trophon
antiquum.
l
Emergence succeeding the denudation of the Middle Sands
| of Antwerp.
: é Sands of
Middle Littoral zone of the} pone. ete Sands of Wyne-
Sands of Port of Borsbeek;| vith rsdcardia| hems ete., with
Antwerp. Bryozoan rock. aa Bryozoa.
Partial emergence of the Lower Sands of Antwerp.
(
| : Gravelly sands of
Antwerp. >
Sands of Diest, Sands with Pec-
Lower or Diestien. ; tunculus pilosus,
Sands of 1 Ferruginous of the environs
Antwerp. sands. rig ran Puen of Antwerp. Sands of Ede-
Shell-banks of j|_———CSSC#d:d SHEM With Pa72OO~
Bolderbeg. pea Menardi.
L L
MIOcENE i E : .
fee Emergence succeeding the denudation of the Oligocene deposits.
PPER
OLIGOCENE.
i ig ich dhe enact
MIDDLE | Upper ‘ . Sand 1 f
; li Bolderian’ andy clay o
OLIGOCENE. é Rupélien. aaiawot Bolder. Bergh, etc., with
\ berg. Nucule. Rupélien clay
| of Boom, ete.
U

co
¥

408 Reviews—Angelin’s Silurian Crinoidea.

rolled and water-worn bones, many of them belonging to Cetaceans
that could not have lived in the shallow seas of the period: these
remains have been derived mostly, if not entirely, from the Middle
Sands, where they abound in the unrolled and connected state.

Littoral beds occur Hast of Antwerp, indicating a later advance
of the sea, possibly that produced by the depression which in
Suffolk introduced the Chillesford series.

The geography of the Upper Sands period resembled in the main
that of the preceding epoch, with the addition of a wide sheet of fresh
or brackish water, which stretched from Austria to Tartary, and left
as its isolated relics the Black, Caspian, and Aral seas.

[Copious lists of fossils, with statistical analyses of each, are
adduced by the author in proof of his views, but for these the reader
is referred to the original. The author desires the writer of this
notice to add that he will be happy to present a copy of the work
to any one interested in the subject. Applications may be made to
W. Whitaker, Esq., B.A., F.G.S., Museum, Jermyn Street, S.W.]

W. H. D.

ey eS

I.—IconocrapHia CrinorpEorum 1n Srratis SvuEcrm SILuRICTS
Fossinium Avuctorse N. P. Anertin. Opus Postumum Hprnpum
Curavir Reaia Acapemia ScrentraRumM Svuecica. Folio, pp.
64. Cum Tabulis XXIX. (Holmiz, Samson & Wallin ; London,
Triibner & Co., 1878.)

HERE is probably no better proof of disinterested regard which

can be displayed for a deceased scientific man, than that his
friends should undertake the very difficult and laborious task of
preparing his posthumous works for publication. It was this feeling
which led the disciples of the illustrious Cuvier to publish “Le

Régne Animal,” and Charles Murchison to edit ‘‘ Falconer’s Paleeon-

tological Memoirs.” A noble example of this self-denying spirit

is shown in the work before us by Prof. S. Lovén, and Dr. G.

Lindstrom, the former a colleague of Angelin’s, and the latter his

recently appointed successor at Stockholm.

The unpublished MSS. of Angelin, handed over to the Academy
by his family, were found to consist of various memoirs on the
Trilobites, Cephalopoda, Graptolites, etc., but for the most part in-
complete and unarranged.

In 1851 he published under the title of ‘ Palzeontologia Suecica ”
the first part of his Monograph of the Silurian Crustacea of Scandi-
navia; the second part entitled “ Paleontologia Scandinavica ”
appeared in 1854, At his death in February, 1876, all the beautiful
plates, 29 in number, published in the present volume, were found
ready prepared and lithographed, part of the text was printed and
part was found in MS. The Editors modestly lay claim only to
the plan and systematic arrangement of the work (except the
Cystidea), they having given Angelin’s own generic and specific
characters, merely reducing the same to order, and adding some
~ needful notes on the synonymy. ‘The name of Prof. S. Lovén,

Reviews—Angelin’s Silurian Crinoidea. 409
however, gives a very high importance to this Monograph, and it is
sure to be largely in demand, so soon as its publication is made
known, especially for the libraries of museums and _ scientific
societies; to all those interested in Silurian fossils it becomes a
necessary work of reference. No more beautiful figures of Crinoids
have ever appeared than those so accurately portrayed in Angelin’s
plates, and the Latin text which accompanies them will render the
work of the highest utility.

The author divides the Crinoidea into two great primary divi-
sions, namely, IJ. CrinorpEA proper ;

and II. CystipEa.
The “‘CrinoIpEA proper” are again subdivided according to the
number of their basal plates into four sections, viz. :—1. Trimera ;
2. Tetramera; 3. Pentamera; and 4. Polymera.

The Cysrrpka are divided into three sections, namely, 1. Apora;
2. Gemellipora; 3. Pedicellata; Rhombifera. The author has
abolished the termination in itées of genera like Hchinospherites,
Caryocystites, Spheronites ; which are printed Hchinosphera, Caryo-
cystis, Spheronis ; but the convenience of the termination in ites as
a ready means of distinguishing generic names applied to fossil
forms from those of existing representative genera (e.g.: Penta-
erinus from Pentacrinites) is too generally recognized and has been
too frequently used to be easily removed from our Nomenclator
Paleontologicus.

The following is the classification adopted by the author for these
two great groups. ?

I. CRINOIDEA PROPRIA. Genus, Clidochirus, Ang. (2 sp.)
Section I. Trimera. », Calpiocrinus, Ang. (4 sp.)
Fam. 1. BriaRrocrINipz. pp, URSA tS (TED)

Gunna eae eerie g. (2 sp.) Fam, 11. IcoTHYoOcRINIDZE.
> 9 . . 42
TERY te Genus, Ichthyocrinus, Conrad (3 sp.)

Genus, Patelliocrinus, Ang. (9 sp.) po, eEpibuneteaaiy See (ER)
Fam. 3. PuaTycrinip&.

Genus, Marsupiocrinus, Phill. (9 sp.)
», Leptocrinus, Ang. (1 sp.)
» Cordylocrinus, Ang. 1 (sp.)
Fam. 4. HaBrocrinip&.
Genus, Habrocrinus, D’ Orb. (14 sp.)
» Pionoerinus, Ang. (5 sp.)
Fam. 5. DEsMmpocRINIDz.
Genus, Desmidocrinus, Ang. (4 sp.)
Fam. 6. ACTINOCRINID.
Genus, Actinocrinus, Miller (9 sp.)
» Leriechoerinus, Austin (9 sp.)
Fam. 7. BARRANDEOCRINIDZ.
Genus, Barrandeocrinus, Ang. (1 sp.)
Fam. 8. SaGENOCRINIDZ.
Genus, Sagenocrinus, Austin (1 sp.)
Fam. 9. TAXocRINIDE.
Genus, Zaxocrinus, Phillips (10 sp.)
», orbesiocrinus, DeKon.(4sp.)
» Gissocrinus, Ang. (7 sp.)
», Myelodactylus, Hall (3 sp.)
Fam. 10. HomatocrinipZ&.
Genus, Homalocrinus, Ang. (1 sp.)
», Lecanocrinus, J. Hall (2 sp.)

Section IT. TeTrRamERa.
Fam. 1. Catyprocrinx (= Euca-
lyptocrinide.)
Genus, Cadlocrinus, D’ Orb. (9 sp.)
Eucalyptocrinus, Goldfuss (7
species).
», Hypanthocrinus,Phill. (3sp.)
Fam. 2. CoRYMBOCRINIDE.
Genus, Corymbocrinus, Ang. (6 sp.)
», Abacocrinus, Ang. (4 sp.)
Fam. 3. MELocRINIDz.
Genus, Melocrinus, Goldf. (5 sp.)
Fam. 4. CyrtTmpocrinIDz&.
Genus, Cyrtidocrinus, Ang. (1 sp.)
Section III. PEnTaMERA.
Fam. 1. PisocrinIDm.
Genus, Pisocrinus, De Koninck (4
species).
Fam. 2. STELIDIOCRINIDZ.
Genus, Stelidiocrinus, Ang. (3 sp.)
», Harmoerinus, Ang. (1 sp.)
Fam. 3. CHIROCRINID@.
Genus, Chirocrinus, Salter (1 sp.)

2?

410 Reviews—Lebour’s Catalogue of Fossil Plants.

Fam. 4. CYATHOCRINIDE. II. CYSTIDEA.
Genus, Cyathocrinus, Miller (14 sp.) Section I. Arora,
», Sicyoerinus, Ang. (1 sp.) Genus, Echinosphera, Wahlenberg.
», Huspirocrinus, Ang. (1 sp.) (1 species).

»» Ophiocrinus, Ang. (1 sp.) » Caryocystis, y. Buch (7 sp.)

Botryocrinus, Ang. (2 sp.) » Megacystis, Hall (2 sp.)

Pb)
Fam. 5. Evucrinipz. Section II. G:
Genus, Eucrinus, Ang. (7 sp.) COMOTL A RE MEUETE ORE:

Twa. @. lORain ae Genus, Spheronis, Hisinger (8 sp.)
Genus, Enallocrinus, D’Orb. (2 sp.) 3, -Hueystis, Ang. (1 sp.)
Fam. 7. CROTALOCRINIDE. » Glyptosphera, Muller (1 sp.)
Genus, Crotalocrinus, Austin (3 sp.) » — Gomphocystis, Hall (1 sp.)
Section 1V. PotymeEra. Section III. PepicELLATA; RHOMBIFERA
Fam. 1. PoLyPELtip#. Genus, Glyptocystis, Billings (1 sp.
y; § 1Y
Genus, Polypeltis, Ang. (1 sp.) », Lepadocrinus, Hall (1 sp.)

The Cystidea have been specially edited by Prof. Lovén. All the
Crinoidea enumerated and described in this work are from Swedish
localities, but many of them are at once seen to be identical with
British Silurian species, and it is for this reason more especially,
that we have to thank Professor 8. Lovén and Dr. G. Lindstrém
for this very valuable contribution to paleontological science,
Strange to relate, save for an exceptional paper here and there, this
beautiful group of the Echinodermata have remained almost un-
noticed in this country. Miller’s Crinoidea (1821) and Austin’s
Crinoidea (1821-44), both rare works, being the only two separate
memoirs published in this country on ‘Stone Lilies.”

IJ.—Caratocur or tHE Hurron Connection oF Fossin Pants,
INCLUDING A SynopticaL List oF THE CHIEF CARBONIFEROUS
SPECIES NOT IN THE CotLEcTIon. By G. A. Lzxpour, F.G.S.
Royal 8vo. pp. 182. (Newcastle-on-Tyne, Published for the
Institute by Andrew Reid, Printing Court Buildings; London,
Longmans and Co., 1878.)

fie work by Mr. G. A. Lebour containing the Illustrations of
the Fossil Plants belonging to the large collection of the late

Mr. W. Hutton, and not published in the “ Fossil Flora,” has been

already noticed in this volume (p. 319). The present work by the

same author may be considered as a companion to the former, and
comprises a catalogue of the specimens in the Hutton Collection of

Fossil Plants in the Newcastle Museum, which is of special value as

illustrating the ancient flora of the Newcastle Coal-field.

Although greater attention has been paid in the Catalogue to such
species as are represented in the Collection, or are figured in the
“ Fossil Flora” of Lindley and Hutton, the student will find most
of the chief Carboniferous species of plants, either not found in the
collection or known as British forms, therein enumerated, as well as
lists of some Triassic or Jurassic plants, thus rendering the work
of greater utility. The genera, with their principal diagnostic
characters, are arranged chiefly according to the system adopted by
Schimper in his Paléontologie Végétale, and the general catalogue
is preceded by an introduction in which the early and present ideas
prevalent as to the stratigraphical value of fossils, and to their
distribution, are briefly stated. J. M.

Dr. John Evans’s Address to Section C. 411

REPORTS AND PROCHHDINGS.
es

British AssocIaTION FOR THE ADVANCEMENT OF SCIENCE.—
Dustin, August 15, 1878—Address delivered to the Geological
Section. By John Evans, D.C.L., LL.D., F.R.S., F.G.S., etc.,
President of the Section.
EF opening the proceedings of this Section, I cannot but call atten-

tion to the fact that the present is the third occasion on which

the British Association has met in this city, its first meeting here
having taken place in the year 1835, or forty-three years ago. On
that occasion, as indeed for many years afterwards, the two distinct,
though to some extent cognate branches of study, Geology and
Geography, were classed in the same Section, and its President was
a man of whom Irish science may well be proud, and who, I am
thankful to say, is still living to enjoy his well-deserved honours—
the veteran geologist, Sir Richard John Griffith, the author of the
first Geological Map of Ireland. It seems hardly credible that the
construction of this map was commenced in the summer of 1812, or
sixty-six years ago; but the records of the Geological Society of
London testify to the still more remarkable fact that Sir Richard
Griffith was elected a Fellow of that Society in 1808,—seventy
years ago. Indeed, in 1854, when the Wollaston medal was
awarded to the then Dr. Griffith, the President, the late Professor
Edward Forbes, spoke as he said reverentially to one of the earliest
members of the Society, and to a geologist who appeared in print
before he, the President, was born. Jt was well said on that occasion
that the map lately mentioned was one of the most remarkable
geological maps ever produced by a single geologist ; and I make no
doubt that those who are at present engaged on the Geological
Survey of this island will testify, as did their predecessors, to the
value of this “ surprising monument of observation and skill.”

When speaking of the Geological Survey of Ireland, it will not, I
am sure, be thought out of place if I offer here a tribute of respect
to the memory of one who was originally a student in the College
within whose walls we are assembled, and who subsequently occu-
pied posts of the highest importance in connexion with the Geological
Society of Dublin and the Geological Survey of Ireland, besides filling
the Professorial Chair of Geology in this University: I mean Dr.
Thomas Oldham, the late Director of the Geological Survey of India.
With the marvellous amount of work which he was enabled to
accomplish in that country you are all acquainted, and you will all
share in the regret that the period of his well-earned retirement—
that ‘“requies optimorum meritorum ”—should have been so quickly
cut short by death. His name will, however, long survive, and
future students of geology will have no difficulty in recognizing the
distinguished labourer in their science after whom the Cambrian
Oldhamia of the Wicklow hills so worthily received its name.

But to return to this Association.

On the next occasion of its meeting in Dublin, in 1857, Section C.
had become devoted to Geology alone, and Geography was excluded,

AE) —. Reports and Proceedings—

the President being Lord Talbot de Malahide, a nobleman whom also
we still have among us, and who is alike well known to archeologists
and geologists.

As the last meeting of the Association in this city took place
twenty-one years ago, it would at first sight appear that in opening
our proceedings I might with propriety dwell on the progress which
has been made within that period in the development of the geology
of Ireland. I must, however, remind you that it is only four years
since the Association held its meeting in what I may almost call the
neighbouring town of Belfast, when the accomplished chief of the
Geological Survey in Ireland presided over this Section and delivered
an address, in which some of the more interesting features of the
country, especially those of the volcanic district of the north-east of
this island, were discussed. During the present year, moreover, he
has published his comprehensive work on the Physical Geology and
Geography of Ireland, which I commend to you as far more likely to
call your attention to the characteristic features of the country and
the latest discoveries with regard to its geology than anything I
could compile.

In addition to this, there has appeared during the present year
another interesting volume, which records the impressions of a highly
intelligent foreign geologist on visiting this country. I mean the
« Aus Irland” of Dr. Arnold von Lasaulx, Professor of Mineralogy
in the University of Breslau. For this volume, in which shrewd
remarks on the country and its inhabitants are mingled with geolo-
gical observations and valuable comparisons of the Irish formations
with those of other countries, we are indebted to the meeting of the
British Association having been held two years ago at Glasgow,
which attracted the author to visit the British Islands.

So much having lately been published upon the geology of this
country, I shall content myself with making a very few general
observations with regard to it, and propose subsequently to touch
briefly on some of those questions which, within the last twelve
months, have occupied the attention of those who are engaged in the
advancement of our science.

As to the geology of this country, I may observe that we are
here assembled just on the edge of that great central plain which
forms so important a feature in the map of Ireland, and which
stretches from Dublin Bay on the east coast to Galway Bay on the
west, with hardly a portion of it attaining to an elevation of three
hundred feet above the sea, over a tract of country nearly one
hundred and fifty miles in extent in almost every direction.

The boundaries of this great plain and those of the Carboniferous
Limestone almost coincide, so that we have here the somewhat
remarkable feature of a formation which in England is of such a
character as to have received the name of the Mountain Limestone,
constituting in the neighbouring island nearly the whole of the plain
country. In some of the north-western counties, however, as for
instance Fermanagh and Sligo, it assumes its more mountainous
character. Nearly the whole of this central plain is overlain with

Dr. John Evans’s Address to Section C. 413

boulder clay, limestone gravel or middle drift, and extensive bogs,
so that the subjacent rock is but occasionally seen. In several places
detached bosses of Old Red Sandstone rise through the limestone,
and there is also good reason for believing, with Professor Hull, that
the whole of the area was at one time covered with the upper
members of the Carboniferous group, including the true Coal-measures,
of which unfortunately but small patches remain, and those upon the
margin of the plain. From the absence of the Upper Paleozoic,
Mesozoic, and Cainozoic formations over the area, Professor Hull has
arrived at the conclusion that the surface remained in the condition
of dry land, while that of England was being submerged beneath
the waters of the sea, over the bed of which nearly all these forma-
tions were deposited. To a certain extent, however, he leaves it an
open question whether some of the Mesozoic strata which occur over
the north-east of. Ireland may not have been deposited over the
centre and south. The amount of denudation over this central area
has, no doubt, been such that the chances of even Professor Judd
finding traces of these later deposits appear at first sight to be but
small; but whether the whole of this vast amount of denudation is
due to the wasting influence of rain, rivers and other sub-aérial
agents of erosion, is a question which I venture to regard as at all
events open to discussion. It appears to be the case that in some
parts of the North of Ireland the whole of the Upper Carboniferous
beds had been denuded before the deposition of any Permian strata,
as these are deposited immediately on the Carboniferous Limestone ;
and if this amount of denudation had taken place in pre-Permian
times in the north, there seems a possibility of the same having been
the case in Central Ireland. If so, it is possible that some traces of
the later deposits may yet be found on the central plain. Certainly,
if we are still to regard the White Chalk as a deep-sea deposit, the
Cretaceous rocks of the north-east of Ireland must have at one time
extended farther south than they do at present, and somewhere or
other there must have been shore deposits of that period formed
further south than the Upper Greensand of Antrim. The careful
investigations of Professor Judd have largely extended our knowledge
of the Secondary rocks of the western coast and islands of Scotland,
and he has been able to show that the Jurassic series of the Western
Highlands could not have had a thickness of less than three thousand
feet. It is therefore hard to believe that, with such a development in
so closely neighbouring a district, the deposits of the same age in
Ireland can have been restricted to their present area.

Professor Judd considers that the amount of denudation in the
Scottish Highlands since the Mesozoic and even the Miocene period
has been enormous, and that the great surface features of the High-
lands were produced in Pliocene times. It seems therefore possible,
if not probable, that so long a period of exposure to sub-aérial
influence as that assigned to the central plain of Ireland by Professor
Hull, would have resulted in a more uneven land surface than that
which we now find. At all events, the history of this remarkable
physical feature is one which is of high interest, and can hardly as
yet be considered as closed.

414 Reports and Proceedings—

With regard to the mountainous districts surrounding the central
plain, we shall, I believe, have the opportunity of visiting some parts
of the Wicklow Mountains, a district from which a portion, at all
events, of the native gold of Ireland was procured in ancient times,
as indeed it continues to be. Of the abundance of gold in this
country in early times, a glance at the magnificent collection of
ancient ornaments preserved in the museum of the Royal Irish
Academy will serve to give an idea. Hven in times more recent
than those in which the bulk of these ornaments were made, gold
was an important product of this country, and I am tempted to quote
a few lines from an early English poem, “'The Libell of Englishe
Policye,” written in the year 1436. In treating of the commodities
of Ireland, the author says that the country is

‘So large, so gode, and so commodious
That to declare is straunge and merveilous.
For of silver and gold there isthe ore
Among the wilde Irish, though they be pore;
For they ar rude and can theron no skille
So that, if we hadde ther pese and good wille,
To mine and fine and metal for to pure
In wilde Irishe mighte we find the cure ;
As in Londone saith a jewellere
Which broughte from thennes gold oor to us here,
Wherof was fined metal gode and clene,
That at the touch no better coude be sene.”’

Sir William Wilde has observed that the south-western half of
Ireland has yielded a greater amount of gold antiquities than the
north-western, and probably this would hold good with regard to the
production of the metal itself, though it has been found in the
counties of Antrim, Tyrone, and Derry, as well as in those of
Dublin, Wicklow, Wexford, and Kildare.

The north-east of Ireland possesses, however, another geological
feature peculiar to itself in that great expanse of volcanic beds which
formed the subject of Professor Hull’s address to this Section at the
Belfast Meeting. My only object in now mentioning them is again
to call attention to their containing the only remains of a Miocene flora
which are to be found in this island. Analogous beds were detected in
the corresponding basalts in the Island of Mull by the Duke of Argyll
in 1851. With the exception of the Hempstead beds of the Isle of
Wight, which should probably be classed as Oligocene, and the
Bovey Tracey beds of Devonshire, these are almost the only deposits
of Miocene age in the British Isles. The contrast presented by the
scarcity of deposits of this period in Britain with their abundance in
the north-west, centre, and south of France, Switzerland, and gene-
rally in the South of Hurope, is striking. Instead of thick deposits
covering hundreds of square miles of country, like the Miocene beds
bordering the Pyrenees or those of the great system of the Auvergne,
we have small patches owing their preservation either to volcanic
outbursts having covered them up, or to some favourable circumstance
having preserved them from total denudation. Whether we are to
assume, with the late Professor Hdward Forbes, that the general
dearth of these strata in the British Isles arose from the extent of

Dr. John Evans’s Address to Section C. 415

dry land which prevailed during the long interval between the
Eocene and Pliocene periods, or whether we assume the former
existence of widespread marine deposits which have since been
entirely removed, the case is one not without difficulty. At all
events, the absence of representatives of this period within the
British area has a tendency to prevent a due appreciation of the
enormous extent of.the Miocene period being generally felt in this
country. Nor, generally speaking, do we, I think, take a fair esti-
mate of the remoteness in time to which we must date back the
commencement of that lengthened period. Professor Haughton,
judging from the maximum observed thickness of each successive
deposit, has calculated that a greater interval of time now separates
us from the Miocene period than that which was occupied in pro-
ducing all the Secondary and Tertiary strata from the Triassic to the
Miocene epoch, and, without endorsing the whole of my accomplished
friend’s conclusions, I incline to concur in such an estimate. When
it is considered that the Ballypalidy beds of Antrim and the Lough
Neagh clays are the sole representatives in Ireland of two periods of
such length and importance as the Miocene and Pliocene, their high
interest will be more apparent, and I trust that no opportunity of
minutely studying them will be neglected.

There is one other point with regard to Irish geology on which it
will be well to say a few words, though it is of a negative rather
than a positive character. J mean the absence, so far as at present
known, of Paleolithic implements in this country. It is true that
Professor Hull, in the book to which I am so much indebted, speaks
of a raised beach on the Antrim coast as containing worked flints of
that rude form and finish known as Paleolithic; but this is a slip of
the pen, by which the author has fallen into the not uncommon error
of applying a term which is merely significant of the age of the
implements to their external character. However rude may be
the workmanship of the flint implements found at Kilroot, they
belong to the Neolithic, and not to the Paleolithic period. So far
as Iam aware, no example of any implement belonging to the age
of the Mammoth, Rhinoceros and other members of the Quaternary
fauna has as yet been found in Ireland. Indeed, the remains of
Elephas primigenius and its associates are of exceedingly rare oc-
currence in this country, though they have been found with those of
Bear and Reindeer in the Shandon Cave’near Dungarvan. It is, of
course, impossible to foretell what future researches may bring to
light; but judging from analogy, it seems hardly probable that until
ancient river-gravels containing the remains of the Quaternary group
of mammals are found in this island, veritable Paleolithic instruments
will be discovered. The association of the two classes of remains is
so constant that we may fairly assume that the animals formed the
principal food of the Paleolithic hunters, and that any causes which
lead to the absence of the one class will lead to the absence of the
other also.

_ There is, however, one member of that old Quaternary group which
. is far more abundant in Ireland than it is in England or on the Con-

416 Reports and Proceedings—

tinent of Europe—the Megaceros—which has rightly received the
appellation of Hibernicus.

I hope that we may have an opportunity, under the guidance of
Mr. Richard Moss, of seeing some of the remains of this “antlered
monarch of the waste” in the position in which they were originally
interred, and it will be an interesting question for consideration
whether these remains can be regarded as of the same geological age
as those of the English caves and river-gravels, or whether they do
not for the most part belong to what Professor Boyd Dawkins has
termed the Pre-historic period. It seems by no means improbable
that this gigantic stag survived in this country for ages after he had
become extinct in other lands, and that the view held by Professor
Hull of his extinction being due to persecution by man is correct. If
this be so, it would seem to follow that the human occupation of
Treland is of far more recent date than that of the sister country.

And this brings me to one of those questions which have of late
been occupying the attention of geologists. I mean the date which
is to be assigned to the implement-bearing beds of Paleolithic age in
England. Dr. James Geikie has held that for the most part they
belong to an interglacial episode towards the close of the Glacial
period, and regards it as certain that no Paleolithic bed can be
shown to belong to a more recent date than the mild era that preceded
the last great submergence.

His follower, Mr. Skertchly, records the finding of Palzeolithic
implements in no less than three interglacial beds, each underlying
Boulder-clays of different ages and somewhat different characters, the
Hessle, the purple, and the chalky Boulder-clay. This raises two
main questions, first, as to how far Dr. Croll’s theory of the great
alternations of climate during the Glacial period can be safely main-
tained; and secondly, how far the observations as to the discovery
of implements in the so-called Brandon beds underlying the chalky
Boulder-clay can be substantiated. Another question is how far the
Paleolithic deposits can be divided into those of modern and ancient
valleys, separated from each other by the purple Boulder-clay, and
the later of the two older than the Hessle beds. It would he out of
place here to discuss these questions at length. I will only observe,
that in a considerable number of cases the gravels containing the
implements can be distinctly shown to be of much later date than
the chalky Boulder-clay, and that if the implements occur in successive
beds in the same district, each separated from the other by an enor-
mous lapse of time, during which the whole country was buried
beneath incredibly large masses of invading ice, and the whole
mammalian fauna was driven away, it is a very remarkable circum-
stance. It is not the less remarkable because this succession of
different Paleolithic ages seems to be observable in one small district
only, and there is as close a resemblance between the instruments of
the presumedly different ages as there is between those of admittedly
the same date. J have always maintained the probability of evidence
being found of the existence of Man at an earlier period than that of
the post-Glacial or Quaternary river-gravels, but, as in all other cases, .

Dr. John Evans’s Address to Section C. 417

it appears to me desirable that the evidence brought forward should
be thoroughly sifted and all probability of misapprehension removed
before it is finally accepted. In the present state of our knowledge,
I do not feel confident that the evidence as to these three successive
Paleolithic deposits has arrived at this satisfactory stage. At the
same time it must be borne in mind that if we make the Paleolithic
period to embrace not only the river-gravels but the cave deposits of
which the South of France furnishes such typical examples, its dura-
tion must have been of vast extent.

In connexion with the question of Glacial and Interglacial periods,
I may mention that of climatal changes in general, which has formed
another subject to which much attention has of late been given. The
return of the Arctic Expedition, and the reports of the geological
observations made during its progress, which have been published
by Captain Fielden, one of the naturalists to the Expedition, in con-
junction with Mr. De Rance and Professor Heer, have conferred
additional interest on the question of possible changes in the position
of the poles of the earth, and on other kindred speculations. Near
Discovery Harbour, about latitude 81° 40’, Miocene beds were found
containing a flora somewhat differing from that which was already
known to exist within the Arctic regions. ‘The Grinnell Land
lignite,” say the authors of the report, “‘indicates a thick peat
moss, with probably a small lake, with water lilies on the
surface of the water, and reeds on the edges, with birches,
poplars, and taxodiums on the banks, and with pines, firs, spruce,
elms, and hazel-bushes on the neighbouring hills.” When we
consider that all of the genera here represented have their
present limits at least from twelve to fifteen degrees farther south,
while the taxodium is now confined to Mexico and the south of the
United States, such a sylvan landscape as that described seems
entirely out of place in a district within six hundred miles of the
pole, to which indeed, if land then extended so far, these Arctic
forests must have also extended in Miocene times. Making all
allowance for the possibility of the habits of such plants being so
changed that they could subsist without sunlight during six months
of a winter of even longer duration, I cannot see how so high a
temperature as that which appears necessary, especially for the ever-
green varieties, could have been maintained, assuming that Grinnell
Land was then as close to the North Pole as it is at the present day.
Nor is this difficulty decreased when we look back to formations
earlier than the Miocene, for the flora of the Secondary and Paleozoic
rocks of the Arctic regions is identical in character with that of the
same rocks when occurring twenty or thirty degrees farther south,
while the corals, encrinites, and cephalopods of the Carboniferous
Limestone are such as, from all analogy, might be supposed to indicate
a warm climate.

The general opinion of physicists as to the possibility of a change
in the position of the earth’s axis has recently undergone modifica-
tions somewhat analogous in character to those which, in the opinion
of some geologists, the position of the axis has itself undergone.

DECADE II.—YOL. V.—NO. IX. 27

418 Reports and Proceedings—

Instead of a fixed dogma as to the impossibility of change, we find a
divergence of mathematical opinion, and variations of the pole, differ-
ing in extent, allowed by different mathematicians who have of late
gone into the question, as for instance the Rev. J. F. Twisden,! Mr.
George Darwin,” Professor Haughton,® the Rev. H. Hill,* and Sir
William Thomson.’ All agree in the theoretical possibility of a
change in the geographical position of the earth’s axis of rotation
being effected by a redistribution of matter on the surface, but they
do not appear to be all in accord as to the extent of such changes.
Mr. Twisden, for instance, arrives at the conclusion that the elevation
of a belt twenty degrees in width, such as that which I suggested in
my Presidential Address to the Geological Society in 1876, would
displace the axis by about ten miles only, while Professor Haughton
maintains that the elevation of two such continents as Europe and
Asia would displace it by about sixty-nine miles, and Sir W. Thomson
has not only admitted, but asserted as highly probable, that the poles
may have been in ancient times ‘“‘ very far from their present geo-
graphical position, and may have gradually shifted through ten,
twenty, thirty, forty, or more degrees without at any time ny
perceptible sudden disturbance of either land or water.”

Iam glad to think that this question, to which I to some extent
assisted to direct attention, has been so fully discussed, but I can
hardly regard its discussion as being now finally closed. It appears
to me doubtful whether eventually it will be found possible to con-
cede to this globe that amount of solidity and rigidity which at
present it is held to possess, and which to my mind at all events
seems to be in entire disaccordance with many geological phenomena.
Yet this, as the Rev. O. Fisher® has remarked, is presupposed in all
the numerical calculations which have been made. J am also doubtful
whether, in the calculations which have been made, sufficient regard
has been shown to the fact that a great part of the exterior of our
spheroidal globe consists of fluid which, though of course connected
with the more solid part of the globe by gravity, is readily capable
of readjusting itself upon its surface, and may, to a great extent, be
left out of the account in considering what changes might arise from
the disturbance of the equilibrium of the irregular spherical or sphe-
roidal body which it partially covers. It appears to me also possible
that some disturbances of equilibrium may take place in a mysterious
manner by the redistribution of matter or otherwise in the interior of
the globe. Captain F. J. Evans,’ arguing from the changes now
going on in terrestrial magnetism, has suggested the possibility of
some secular changes being due to internal, and not to external
causes ; and if it be really true that there is a difference between the
longest and shortest equatorial radii of the earth, amounting to six
thousand three hundred and seventy-eight feet,® such a fact would

1 Quart. Journ. Geol Soc., 1878, p. 35.

2 Proc. R. S., vol. xxv. p. 328. Phil. Trans., vol. clxvii. p. 271.

3 Proc. R. S., 1877, 1878. 6 Grou. Mage., July, 1878.

4 Grou. Mae., June, 1878. 7 Nature, May 16, 1878.

5 Rep. Brit. Assoc., 1876, p. 11. 8 Thomson and Tait, Phil. p. 648.

Dr. John Evans’s Address to Section C. 419

appear to point to a great want of homogeneity in the interior of our
planet, and might suggest a possible cause for some disturbance of
equilibrium.

I have mentioned Professor Haughton among nase who, from
mathematical considerations, have arrived at the conclusion that a
geographical change in the position of the axis of rotation of the
earth is not only possible, but probable. In a recent paper, how-
ever, he has maintained, notwithstanding this possibility or pro-
bability, we can demonstrate that the pole has not sensibly changed
its position during geological periods. He arrives at this con-
clusion by pointing out that in the Parry Islands, Alaska and
Spitzbergen, there are Triassic and Jurassic deposits of much the
same tropical character, and then by a geometrical method fixing
the North Pole somewhere near Pekin, and the south pole in
Patagonia, within seven hundred miles of a spot where Jurassic
ammonites occur, shows that such a theory is untenable. In the
same way he fixes the pole in Miocene times near Yakutsk, within
eight hundred miles of certain Miocene Coal-beds of the Japanese
islands. These objections are at first sight startling, but I think it
will be found that if, instead of drawing great circles through certain
points, we regard those points as merely isolated localities in a belt
of considerable width, there is no need of fixing the pole of either
the Jurassic or the Miocene period with that amount of nicety with
which Professor Haughton has ascertained its position. The belt
may indeed be made to contain the very places on which the
objection is founded. Still the method proposed is a good one, and
I hope that as our knowledge of foreign geology extends it may be
still further pursued. There is, however, one farther consideration
to be urged, and that is as to the safety of regarding all deposits of
one geological period as contemporaneous in time. Although an
almost identical flora may be discovered in two widely-separated
beds, it appears to me that chronologically they are more probably
of different ages than absolutely contemporaneous; and, inasmuch
as the duration of the Miocene period must have been enormous,
there would be time—if once we assume a wandering of the poles—
for such wandering to have been considerable between the beginning
and end of the period.

I must not, however, detain you longer upon this phase of
geological speculation, but will advert to a subject of more practical
interest, the discovery of Paleozoic rocks under London. So
long ago as 1856 the Kentish Town boring had shown that im-
mediately below the Gault red and variegated sandstones and clays
occurred, which Professor Prestwich regarded as probably of Old
Red or Devonian age. The boring of Messrs. Meux & Co. has
now shown that under Tottenham Court Road, at a depth of little
more than nine hundred feet from the surface, there are true
Devonian beds, with characteristic fossils, and that Mr. Godwin-
Austen’s prophecy of the existence of Palzeozoic rocks at an acces-
sible depth under London has proved true. Professor Prestwich,
from a consideration of the French and Belgian coal-fields, inclines

420 Reports and Proceedings—

to the belief that in the district north of London Carboniferous
strata may be found. Unfortunately the expense of conducting deep
borings, even with the admirable appliances of the Diamond Boring
Company, is so great that I almost despair of another experimental
borehole like that carried out in the Wealden district under the
auspices of Mr. Willett, being undertaken.

In the department of theoretical geology I would call your atten-
tion to some experiments by M. Daubrée, of which he has given
accounts at different times to the French Academy of Sciences. In
these experiments he has attempted to reproduce on a small scale
various geological phenomena, such as faulting, cleavage, jointing,
and the elevation of mountain chains. Although the analogy
between work in the laboratory and that on the grand scale of
nature may not in all cases be perfect, yet these experiments are in
the highest degree instructive, and reflect no little credit on the
ingenuity of the distinguished chief of the Ecole des Mines.

With regard to recent progress in paleontology, I must venture
to refer you to Professor Alleyne Nicholson’s inaugural address
lately delivered to the Edinburgh Geological Society, but I cannot
pass over in silence the magnificent discoveries in North America,
which are principally due to the researches of Professors Marsh,
Leidy, and Cope. The Diceratherium, a rhinoceros with two horns
placed transversely, and the Dinoceras, somewhat allied to the
elephant, but with six horns, arranged in pairs, are as marvellous
as some of the beasts seen by Sir John Maundevile on his travels,
or heard of by Pliny. But perhaps the most remarkable series of
remains ever discovered are those which so completely link the
existing Horse with the Hohippus and Orohippus, and still farther
extend the pedigree of the genus Equus, which had already been
some years ago so ably traced by Professor Huxley.

Of these American discoveries, as well as those made in the
Tertiary beds of Europe, M. Albert Gaudry has largely availed
himself in his recent beautiful volume on the links in the animal
world in geological times, a work which will long be a text-book on
the inter-relation of different orders, genera, and species. I am
tempted to make use of some portions of M. Gaudry’s own analysis
of the book, which he communicated to the Geological Society of
France. Beginning with the Marsupials of the close of the Secon-
dary and beginning of the Tertiary period, he shows that they are
succeeded by such animals as the Pterodon, the Hyenodon, the
Proviverra, and Arctocyon, which present a mixture of marsupial
and placental characters, and to some extent justify a theory of the
transition from one order to the other. He next examines the
marine Mammalia, and points out that, so far as at present known,
they make their appearance later than those of the land, and that
the examination of the pelvis of the Halitherium tends to support
the idea that the mammals, such as the Sirenians, which at the present
day have no hind-limbs, are descended from terrestrial quadrupeds,
for those limbs in the Halitherium are much less reduced than in its
recent successors, the dugong and manatee. After tracing the

Dr. John Evans’s Address to Section C. 421

numerous links which are to be found between the extinct and
living Pachydermata, he proceeds to show that, notwithstanding the
great distance between them and the Ruminants, transitions may be
seen. The earliest ruminants were devoid of horns and antlers, but
possessed upper incisors, and by a comparison of the molars of
different genera it may readily be conceived how the large bosses of
the omnivorous teeth of the pachyderms gradually shaded into the
small crescents of the teeth of the ruminants. At the same time the
passage from the heavy and complicated extremities of the limbs of
the pachyderms to the simpler and lighter feet of the ruminants can
be traced. The history of the Horse family is also discussed, and the
descent of existing proboscidians from the mastodonts is shown to be
probable, though the previous forms from which the mastodonts and
dinotheria are derived are as yet unknown. Nor can the origin of
the Carnivora as yet be suggested, though passages between the six
existing families of the order may be observed. In conclusion,
M. Gaudry devotes a chapter to the Quadrumana, and thinks that
paleontological observations tend to diminish the isolation in which
these mammals now stand with regard to the other orders.

One of the most important features insisted on by Mons. Gaudry
is that to which I have already alluded—the development of the
complicated molars of most mammals. His view is that by a com-
parison with early and with foetal forms the probability may be
shown of these compound teeth being made up of what in earlier
forms were simple teeth—or, as he termed them, denticules—which
have coalesced in the same manner as have some other parts of the
normal bony skeleton. In the compound teeth the denticules in
some cases preserve their original conical form, as in the pig tribe ;
in others are elongated transversely, so as by their junction to form
ridges, as in the tapirs; while in others, again, they are drawn out
into longitudinal crescents, as in the ruminants. Between these
forms there are, of course, innumerable transitions. They do not,
however, appear to me to affect the importance of Mons. Gaudry’s
observations, which must be regarded as of the highest value in all
attempts to trace the inter-relation of different forms of mammalian
life. I must not, however, detain you longer on this subject, as I
trust that I have said enough to show the importance and interest of
this book.

The discoveries of early forms of birds with teeth do not come
within M. Gaudry’s province; but Professor Marsh has largely
added to our knowledge of these remarkable forms. The Tertiary
Odontopterya toliapicus from Sheppy, described by Professor Owen,
seems rather to be endowed with bony tooth-like processes in the
jaw, than actual teeth, and the head of the Argillornis from the same
locality is at present unknown. But the Hesperornis and Ichthyornis
from the Cretaceous beds of America possess veritable teeth, in the
one case set in a long groove in the jaw, and in the other in actual
sockets. Such intermediate, or, as Professor Huxley would term
them, intercalary forms, tend materially to bridge over the gap
which at first sight appears to exist between reptiles and birds, but

i

422 Correspondence—Ur. G. A. Lebour.

which to many paleontologists was far from being impassable, long
before the discoveries just mentioned. The amphiccelous character
of the vertebree of Ichthyornis presents another most remarkable
peculiarity, which is also of high significance. I hear rumours of
the discovery of another Archgopteryx in the Solenhofen Slates,
which is said to present the head in a much more complete condition
than that in which it occurs on the magnificent slab now in the British
Museum. As yet, I believe, the jaws have not had the matrix
removed from them ; but should they prove to be armed with teeth,
it will to me be a cause of satisfaction rather than surprise, as con-
firming an opinion which some fifteen years ago! ] ventured to
express, that this remarkable creature may have been endowed with
teeth, either in lieu of or combined with a beak.

I must not, however, detain you longer with any of these general
remarks, which are, moreover, becoming somewhat egotistic, but
will now proceed to the business of this Section, in which I hope
that more than one paper of great value and interest will be forth-
coming.

CORRESPONDENCE.

THE MONTE GENEROSO BEDS.

Sir,—The French Geologist’ who supplied information to your
correspondent, the Rev. E. M. Cole, respecting the age of these beds
(Grout. Mac., Decade II. Vol. V. p. 878), provided him with an
order of succession which has been well known for many years.
But if the divisions and their relative positions be clear enough,
their correlation with members of the Mesozoic series in England is
fraught with considerable difficulty.

The Como deposits in question include all the representatives of
the Lias and Oolites and something more. Taking them one by one
in descending order, as given by Mr. Cole’s informant, we have: _
1. Majolique: A white compact limestone, the celebrated Majolica

marble of the Italians. This must not be mistaken for the very
similar Biancone, which was for a long time confounded with it,
but which is now known to be of Neocomian age, and conse-
quently newer than the Majolica. The latter is not only like
Chalk in appearance, but is, like it, also characterized by the
presence of flints in nodules and bands; it is often dolomitic and
contains but few fossils, principally Trigonellites and rarely
Ammonites.

2. Calcaire rouge: The Calcare rosso ammonitifero of Lombardy, not
altogether the representative of the division which goes by that
name in the Apuan Alps. This red deposit teems with Ammo-
nites of species which, to the confusion of the paleontologist,
are elsewhere characteristic of various horizons from the Lower
Lias to the Upper Oolite.

1 Nat. Hist. Rev., vol. v. p. 421. According to Dr. Haberlein, the possessor of
the second specimen, the jaws are armed with teeth ! thus confirming Dr. John Evans’s
opinion founded on an examination of the specimen preserved in the British Museum ;

where, on the slab of stone which contains it, a small detached jaw with teeth is to
be seen lying.—Eprr. Grou, Mag.

Correspondence—Mr. G. A, Lebour. 423

3. Calcaire gris (not grés): The ornamental marble of Saltrio, con-
taining Ammonites Buckland.

4. Calcaire noir: The black marble of Varenna. This is the base of
the “Jura Lombard.” Beneath it occur in places, and especially
between Lakes Lugano and Como, (5) some extremely interesting
black fossiliferous shales, which have been referred to the St.
Cassian Group by Escher v. d. Linth. Below these again comes

6. The Conglomérat marneux: in which fossils are not known, but
which is referred to the Keuper horizon by Omboni.

How very different a set of deposits we have here from anything
to be found in England between Trias and Neocomian will be seen
at once; but if an attempt at correlation could serve any useful pur-
pose, it would be something like this:

Biancone. Lower Neocomian of Speeton.
Portlandian.
Kimmeridgian.
Majolica. Corallian.
Oxfordian.
Lower Oolite.
Calcare rosso ammonitifero Upper, Middle, and Lower Lias (in
(= Calcatre rouge). part).
Marmo di Saltrio Lower Lias (Ammonites oxynotus and
( = Caleatre gris). Amm. Bucklandi horizons).

Calcare degli stampi (=Caleaire noir). | White Lias.

Guggiate Beds. Rheetic.

Green and Red Marls (= Conglomerat | Keuper.
MArNneUuL) .

It should be noted that all these divisions are perfectly conform-
able, and that, notwithstanding the very marked difference in colour,
the white majolica and the red ammonite bed are, paleontologically
speaking, one continuous whole.

Much information (and extremely varied, for no two, of the earlier
authors at least agree in their interpretation of the facts) on this
subject will be found in the papers of Pasini, Catullo, Curioni, de
Filippi, de Collegno, Omboni, etc. From a paper by the last-named
geologist, much of the above matter is taken.

The “ Caleare rosso” of the Apuan Alps, the vicissitudes of which
I described in 1876,' appears to be probably the equivalent of the
Marmo di Saltrio. G. A. Lepour.

2, WoopHovsE TERRACE, GATESHEAD-ON-TYNE.

1 «The Carrara Marbles,’ Grou. Mac., Decade II. Vol. III. p. 289.

424 Correspondence—Mr. Horace B. Woodward.

PROFESSOR PHILLIPS ON THE DEVONIAN QUESTION.

Sir,—The address delivered in 1869, by John Phillips, at West-
ward Ho! and which has just been communicated by Mr. Hall (see
Gero. Mae., July, 1878, p. 307), seems to contain the latest views
of that geologist upon the Devonian rocks, though not, I believe, his
latest expression of them. A more recent statement is given in the
‘Geology of Oxford and the Valley of the Thames” (1871), pp. 79,
80. As far as I can understand, these views of Prof. Phillips do not
differ so very materially from those advocated by Jukes. In the
address just mentioned, Phillips says, “Gentlemen of Devon, never
give up the independence of your country, hold to the North Devon
series, and if it is the case, as Mr. Godwin-Austen invites us to be-
lieve it is, that they do not belong to the Old Red Sandstone series,
do not let us conclude that because they do not belong to that par-
ticular class, they are nothing at all.”

In the “Geology of Oxford,” etc., are the following passages,
“The Old Red Sandstone is followed in Devonshire, and still more
remarkably in the South of Ireland, by a series of shales, grits, and
limestones, with a large suite of fossils, having on the whole a con-
siderable analogy with the still richer associations of marine life in
the Carboniferous Limestone... . . Near Linton, in North Devon,
and south of Plymouth, we may satisfy ourselves of the fact that Old
Red Sandstone underlies the Devonian beds. ... . From this series
of rocks to the Carboniferous strata which succeed, the transition is
easy, SO easy indeed that, in the opinion of Sir R. Griffith and Mr.
Jukes, the whole of the Devonian series may be united with the
lowest members of the Irish Carboniferous group (Yellow Sandstone
and Carboniferous shale). What seems ascertained truth is the close
approximation in time, in character of deposition, and in forms of
life, of the South Hibernian and South Welsh rocks; while the
North Devonian strata contain with these a somewhat lower group,

‘not distinctly represented in Wales or Ireland.” !

Here, then, we find that Professor Phillips would separate the Old
Red Sandstone from the Devonian rocks, while he speaks of the
Devonian fauna as “continued into the cognate though later Car-
boniferous Period.” I think by the term Carboniferous Period, as
here used, Professor Phillips referred especially to the fauna of the
Carboniferous Limestone. But his views, so cautiously expressed,
seem to approximate towards those of Jukes, and to render their
differences chiefly a question of terms or classification. Certainly
they are distinct from the contention of Mr. Etheridge, “that the
Devonian system, as a group of strata, both physically and paleon-
tologically, may be (as long ago proposed) naturally and con-
veniently divided into a Lower, a Middle, and an Upper Series, and
that there is valid reason for believing that this system equalled in
time the whole of the deposits of the Old Red Sandstone proper.”
(Quart. Journ. Geol. Soc., vol. xxiii. p. 686.) A statement which
is perhaps a little modified by a subsequent admission (p. 690) that,

1 These remarks were quoted by me in a review of the Devonian Question, Quart.
Journ. Science, Jan. 1873.

Correspondence—Prof. John Milne. 425

“On the other hand, there may be grounds for endeavouring to
establish contemporaneity between the Upper Devonian series of
North Devon and the Carboniferous Slates of the South of Ireland,
upon the principle of geographical rather than chronological distinc-
tion.”

Guided by the opinion of Professor Phillips, we should certainly
be warranted in keeping distinct the application of the terms Old
Red Sandstone and Devonian, which, when used synonymously, are
productive of much confusion. In this case of course the Lynton
Sandstone (Foreland Group) of North Devon should be classed as
Old Red Sandstone, and excluded from the Devonian system.

Movseno1p, Norwicu, 10th August, 1878. Horace B. Woopwarp.

* COAST ICE ON A RISING AREA.” REPLY TO DR. G. LINNARSSON.

Sir,—Two days ago, on returning from a long geological excur-
sion which I had been making in the interior of Japan, I received
several numbers of the GEonoctcan Macaztne. In the Number for
February I read the letter of Dr. G. Linnarsson of Stockholm, criticizing
_ my views of glacial phenomena which appeared in a series of articles
in your Magazine, under the title “Across Europe and Asia.” If
Dr. Linnarsson had awaited the completion of my article, or if he
had only carefully interpreted those portions of it that were in his
possession at the time he wrote, I think he would have seen that he
was campaigning against an imaginary foe.

He has failed to observe that my travelling notes are only a
series of fragmentary jottings collected and subsequently written out
under considerable difficulties. Under such circumstances, feeling
my fallibility, I held myself open to correction, and it is therefore
now with pleasure that I thank Dr. Linnarsson for having incident-
ally pointed out my oversight in ascribing the presence of erratics at
higher levels than their parent rock to the action of coast-ice on a
rising area. :

I say oversight, advisedly, first because this is a phenomenon which
is so universally referred to by all writers on these subjects, and
secondly because previously I myself, in the GronocicaL Macazrnn,
Dee. II. Vol. III. Nos. 7, 8, and 9, when writing more generally upon
coast-ice, have referred to these appearances as being due (as many
before me have suggested) to the action of coast-ice on oscillating or
sinking areas. For example, in one place I make the following
note: ‘‘ Other blocks again are shown to have travelled from low
plains to the summit of hills, which is explained on the supposition
that the land at the time of their deposit was slowly subsiding, and
the ice-fields of successive years were raising the blocks higher and
higher.”

With regard to the remainder of Dr. Linnarsson’s criticisms, which
form the substance of his correspondence, I hardly feel that I can
acquiesce in the manner in which he has treated my communication.
One of my chief objects, when speaking of the appearances which I
saw along the coast of Finland, was to show that it was by no means

426 Correspondence—Prof. John Miine.

necessary for us to imagine that every surface which had been
scratched and rounded must have been produced by a continental
sheet of ice, and it was only to explain some of these phenomena that
I suggested an agency which I believe has been hitherto overlooked,
namely, that of coast-ice upon a rising area.

Dr. Linnarsson seems to say that from observations made from
railway waggons and steamers I think myself “enabled to refute the
views since many years universally held by Scandinavian geologists.”

If he had only read my paper attentively, he would have seen that
my views respecting the glaciated appearance of low countries like
that I saw in Finland are by no means only founded on what I
saw from the railway waggons of Scandinavia and the steamers of
Finland, but also from observations made upon the shores of some
“4000 miles of coast in Labrador and Newfoundland.”

To convince Dr. Linnarsson that I am not acting so impulsively as
he would give the readers of the Gronogrcan Macazine to under-
stand, I may refer him to several other papers which I had pre-
viously written upon the same subject (see Grou. Mae., Decade II.
Vol. III. 1876, pp. 808, 345, 408; see also Quart. Journ. Geol. Soe.
1877, vol. xxxiii. p. 929). If, even without reading these papers, he
had only waited until the completion of my travelling notes, he
would have saved himself the necessity of proving the former
existence of a glacial climate.

In several portions of my paper I very distinctly incline towards
what Dr. Linnarsson would make me appear to be so antagonistic to.
Thus, for example, in the Guotocican Macazine, February, 1878,
near the end of my paper, I most clearly state that my arguments
antagonistic to the existence of polar ice caps have ‘only been in
regard to the production of certain phenomena.” Amongst these
apparent glacial phenomena are appearances which may be seen in
many portions of the world along coast-lines, islands and low-lying
countries, and as illustrations of these I have taken portions of
Finland, Labrador, and Newfoundland. Dr: Linnarsson admits the
abrading power of coast-ice, and I also think that, in common with
other geologists, he will admit that there is such a phenomenon as
the slow elevation of the land. If he does this, I think he must
then admit the existence of those effects which must result from the
combined influence of these two agents. That all the so-called
glacial phenomena to be seen in Sweden and other countries are by
any means to be attributed to this action, ] by no means wish to
advocate, but at the same time I must confess that I should find it
difficult to prove that the scratches and furrows which I have often
seen upon a coast-line, and which the inhabitants tell me were pro-
duced by the shore ice of last winter, were the consequence of some
continental glacier which may have perhaps existed some 10,000
years ago. It would be equally antagonistic to my sense of reason
to endeavour to prove a similar origin for the furrows and scratches
which in a rising area graduate upwards and backwards from those
produced last year at the water’s edge.

The chief point which I wished to advocate in my paper was that

Oorrespondence—Prof. John Miine. 427

the action of coast-ice on a rising area has produced many pheno-
mena which are inexplicable by the action of continental glaciers.
On the other hand, Dr. Linnarsson shows that there are phenomena
which I did not even refer to in my paper that may have been pro-
duced by a continental sheet of ice, but not by coast-ice.

To all this I see no objection, and so long as Dr. Linnarsson only
claims a reasonable proportion of the so-called glacial phenomena as
the result of the action of his continental sheet, I shall be content
to see the leavings sifted and a certain proportion of them set down
to the credit of coast-ice acting on a rising area.

So much then for the general argument embraced in Dr. Linnars-
son’s communication. I will now turn to one or two of his details.

First, I cannot agree with Dr. Linnarsson that the scratches pro-
duced by coast-ice are “independent of the slope of the land.” In
making this statement, it appears to me that he has apparently
omitted to notice the most effective of the methods in which coast-
ice acts. Looking at a coast-line generally, the slope of the land
will be at right angles to its direction, and the scratchings and
furrowings due to the action of ice being produced by the driving
in or “raftering” of the pack-ice upon the ice-foot or “ balacada,”
the markings which are produced must be parallel to this move-
ment, that is, at right angles to the shore-line. If, on the other
hand, the “currents and winds” are very oblique or parallel to the
coast-line, the balacada will usually remain unmoved, and will only
be chafed as the pack-ice floats along its outer edge, or what the
inhabitants of Labrador and Newfoundland call the “ drain.”

If we consider the way in which scratchings are produced by the
dragging and sliding of coast-ice back towards the sea, and say
the markings which will remain behind are independent of the slope
of the land, we shall next, perhaps, be induced to say that the
direction in which rain runs from the roof of a house is also inde-
pendent of the direction of its greatest slope.

At the commencement of Dr. Linnarsson’s letter, when speaking
of my arguments, he says, ‘“‘I think that most of your readers do
not need to have the failings of such reasonings pointed out.” The
reasons here referred to are my arguments in reference to the action of
coast-ice. What must the readers of the GuotocicaL Magazine think
of the authoritative statements and arguments of Dr. Linnarsson,
when they read at the termination of his letter that ‘The rocks (on
the coasts of Sweden and Finland) are there so hard and compact,
and the force of the waves so small, that their action on the rock
surface is hardly perceptible. A rock may be exposed there for
hundreds of years to the waves without the finest scratches being
abraded.” Whilst remembering that a rock exposed to the waves
must also be exposed to the atmosphere, six lines further on they
then read that, “In the open air the scratches usually become
obliterated in a few years,” etc. ?

All this is brought forward, I may mention, in opposition to an
opinion I expressed that all glaciated rocks, in order that their
scratched surfaces may retain their character, ‘‘must always have

428 Correspondence—Prof. T. G. Bonney.

remained above sea-level or else have been shielded by some pro-
tective covering during both subsidence and elevation,” a view from
which I do not yet see the slightest reason to waver. If the country
is a cold one, such for example as we might imagine during the
retreat of a continental covering of ice from the face of Sweden, and
depression were taking place, coast-ice, it seems to me, would grind
every furrow from the surface of the rocks, as they gradually sank
down at any particular.time, the abrading action taking place from a
level above that of high water to one below low water, and every
portion of the surface of the country being many thousands of years
in sinking through the abrasion region. On elevation this erasing
action would be repeated. If the country were not a cold one,
atmospheric agencies, a continual exposure to an artillery of pebbles,
the grinding of sand, and like causes, would, according even to the
most modest calculations, have sufficient time for the production of a
similar result. JoHN MILNE.

YeEDo, June 17, 1878.

THE QUARTZITES OF THE BUNTER CONGLOMERATE.

Str,—As I happen to be very familiar with the quartzites of the
Bunter Conglomerate of the Midland Counties, may I be allowed to
question the correctness of one or two statements which have been
lately made in the pages of the Grotocican Magazine. 1. I can-
not admit that the typical quartzite of this Conglomerate is litho-
logically identical with that from Budleigh Salterton. 2. I greatly
doubt whether the fossiliferous pebbles from the Birmingham Drift,
now in Jermyn Street Museum, have been derived from the Bunter
Conglomerate. At any rate, the rock, though a quartzite, does not
appear to me that of the Bunter pebbles: it more nearly resembles
that from the Lickey. 3. I have many times searched for fossils
in the pebble beds of Staffordshire, and have only twice found them’:
these were obscure annelid burrows. Hence I cannot admit that
there is any paleontological identity with the Budleigh Salterton
rock. From physical considerations it would require very strong
evidence to induce us to believe that the Midland Counties pebbles
came from §. Devon. J have no doubt Professor Hull is right in
assigning to them a northern origin (Permian and Trias of Midland
Counties, p. 60). Ihave myself identified them in more than one
place in Scotland. For example, they abound in a conglomeratic
red sandstone of Lower Carboniferous age in Arran, mixed, how-
ever, with fragments of schist, greywacke, ete. These softer rocks
have almost invariably perished on the southward journey—so that
it is a case of survival of the most durable. T. G. Bonney.

Sr. Joun’s Contece, CAMBRIDGE, Aug. 12.

\

OBITUARY. 429
—__»_—_

RICHARD DAINTREE, C.M.G., F.G.S.
Born DrEcEMBER, 1831. Diep June 20, 1878.

AUSTRALIAN GuroLocy has sustained another severe loss in the
death of Mr. R. Daintree, C.M.G., F.G.S., following, as it has done,
so rapidly on that of the Rev. W. B. Clarke, F.R.S.!

Richard Daintree was born at Hemingford Abbotts, Huntingdon-
shire, in December, 1831, and was educated at the Bedford Grammar
School, and Christ’s College, Cambridge. In consequence of delicate ~
health, Mr. Daintree was recommended a voyage to Australia, and
he accordingly set sail for Melbourne, where he landed in the latter
part of 1852. A taste for scientific pursuits brought him in contact
with Mr. A. R. C. Selwyn, the Government Geologist of Victoria,
whose Assistant he became in 1854; but finding that a more practical
acquaintance with Chemistry and Assaying, than he at that time
possessed, would prove beneficial to his prospects, he returned to
England in 1856, and entered Dr. Percy’s Laboratory. Here he
worked from November, 1856, to May, 1857, and became a practised
and efficient assayer, to which he added a knowledge of practical
photographic chemistry.

In August, 1857, Mr. Daintree returned to Melbourne, and in 1858
was appointed Field-Geologist on the Geological Survey of Victoria,
which had by this time been established on a firm basis through the
energy of its Director, Mr. A. R. C. Selwyn, F.R.S. During his
connexion with the Victorian Survey, for the next seven years, Mr.
Daintree was occupied in field work and exploration of no ordinary
nature. He commenced in the Western-port district, directing his
attention to the Cape Patterson Coal Series. In exploring the Bass
River, Daintree underwent much hard camp life, and endured many
privations in penetrating the dense scrubs of that district.

The Geology of the Bellerine District? next engaged Mr.
Daintree’s attention, lying between Geelong and Queenscliff. A
series of extensive borings for Coal, through the Mesozoic rocks, were
there superintended; but, although about 4000 feet of strata were
passed through, the search was fruitless. On leaving Bellerine in
1861, Mr. Daintree was joined by Mr. C. S. Wilkinson (now Govern-
ment Geologist for N. S. Wales) as his Assistant, and until March,
1864, they were conjointly engaged in the geological survey of the
country from Bass’ Straits on the south, to Bacchus Marsh on the
north, including the important agricultural and pastoral districts of
the Barrabool Hills, the Annakie Hills, the Werribee River and
‘Ballan district. At the end of May, 1863, a most important report
was prepared by Mr. Daintree, on this work, and when published it

1 See Obituary Notice of Rev. W. B. Clarke, Grou. Maa. August, p- 379.

2 Report on the Geology of Bellerine and Pagwit, with Special Reterence to the
probable Existence of workable Coal Seams in those Parishes. By R. Daintree.—
Vict. Geol. Survey Report, 1861-62, No. 43, folio, pp. 16-23. Melbourne.

Maps.—Sheet 23 N.E. (Portarlington); 23 8.E. (St. Leonards); 23 S.W.
(Point Henry); Sheet 29 N.E. (Queenscliff) ; 29 N.W. (Lake Connewarre). By
R. Daintree, under the direction of A. R. C. Selwyn.

430 Obituary—Richard Daintree, CY..G., F.G.S.

was prefaced with the following official remarks: “'The following .
interesting Report ... . contains so much matter having an im-
mediate reference to the economic development of the Colony, inter-
woven with purely scientific observations, that it has been deemed
desirable to publish it in extenso, without waiting to produce it in
connexion with a series of similar reports or memoirs,” etc.

Some of the less known parts of Victoria were explored by
Messrs. Selwyn and Daintree in company, and on one of these trips
a tour of the gold-fields was made, and many most interesting
photographs illustrative of gold-field geology were taken.

In 1864 Daintree resigned his connexion with the Victorian Civil
Service, and entered into pastoral pursuits on the River Clarke,
Burdekin River, North Queensland; but during one of the several trips
made by him about that time between Melbourne and the northern
colony, he found time to make a partial examination of the N. 8.
Wales Coal-field. The results of his observations! are important,
because they tended in a great measure to support the views held
by the late Rev. W. B. Clarke on the age and position of the Coal-
measures of N.S. Wales. Notwithstanding the danger and hardships
of a “squatting ”’ life in lat. 19°S., Mr. Daintree’s geological studies
were not neglected, for several useful examinations of his own district
were made. In 1866 a paper was read by him before the Royal
Society of N. S. Wales, to the effect that auriferous tracts would be
found in the neighbourhood of the Endeavour River, a statement
which was borne out eight years later by the discovery of the Palmer
Gold-field.

The full report,’ previously referred to, bearing on the work done
by Daintree and Wilkinson in the Ballan district of Victoria, was
not published in detail until 1866, when it appeared as one of the
regular reports of the Survey. In this report Daintree discussed
at some length the various modes of occurrence of gold, and in
reference to the origin of the precious metal, he said: ‘“‘I had long
ago come to the conclusion, ‘that most, if not all, the gold in the
quartz reefs was derived from the rocks in which these reefs occur.
That the strata themselves received their supply of gold at the
period of their deposition from the ocean in which they were de-
posited. That organic matter, and the gases generated therefrom
on decomposition, sulphuretted hydrogen, etc., was the cause of the
precipitation, and that the amount of metallic deposit was in pro-
portion to the amount of organic matter deposited with the oceanic

1 On the Age of the N. 8. Wales Coal-beds. By R. Daintree.—The Geologist,
1864, vol. vii. pp. 72-79.

2 Report on the Geology of the District of Ballan, including Remarks on the Age .
and Origin of Gold. By R. Daintree. Vict. Geol. Survey Report, 1866, No. 16,
pp. 11, folio. Melbourne.

Maps.—Sheet 8 S.E. (Tarneit) ; 8 S.W. (Mount Mary); Sheet 12 S.E. (Balliang) ;
Sheet 19 N E. (Annakie Hills); 19 S.E. (Station Peak); 20 N.W. (You-Yangs) ;
20 S.W. (Rothwell); Sheet 28 N.W. (Point Wilson, ete.) ; Sheet 24 S.E. (Geelong) ;
Sheet 28 N.E. (German Town); and Sheet 29 S.W. (Thompson’s Creek). By R.
Daintree and C. 8. Wilkinson, etc.

Obituary—Richard Daintree, C.M.G., F.G.S. 431

sediment. The subsequent plication and desiccation of the sediment
caused fissures, into which the mineral waters percolating, the
boundary rocks flowed and were decomposed, and their mineral
contents were precipitated, possibly by magnetic currents, thus
causing mineral veins.”

The geological and other scientific acquirements of Richard Daintree
were not lost upon the Queensland Government, for in 1867 they
requested him to make an examination of the Cape River district,
which resulted in the opening up of the Cape River Gold-field.*
In 1869 he was appointed Government Geologist for North Queens-
land, whilst the late Mr. C. D’Oyley H. Aplin was appointed to a
similar post in the southern part of the same colony. The Queens-
land Government were able to secure the latter gentleman’s services
through the parsimony of the authorities of the Victorian Colony in
breaking up one of the most complete Geological Surveys ever
organized, except perhaps that of the United States Territories, under
Dr. F. V. Hayden. During the three years intervening between
1869-71, Mr. Daintree examined large areas in North Queensland,
including those of the Gilbert? and Etheridge Rivers, and the
Ravenswood district, which have since proved highly auriferous and
remunerative to those employed on them.

The importance of proper and efficient representation at the London
Exhibition of 1872 was not lost upon the Queenslanders, for in 1871
Mr. Daintree was appointed Special Commissioner, and in consequence
left the colony. The wisdom of the Colonial Government’s selection
cannot be better borne out than by the admirably organized and
arranged Queensland Annexe of that and succeeding Exhibitions, in
the administration of which Mr. Daintree took the entire super-
intendence and most active part, although latterly much broken in
health. The office of Agent-General in London to the Colony of
Queensland falling vacant at this time, the subject of our notice was
appointed to it in March, 1872, a post held by him until 1876, when,
in consequence of ill health, he was obliged to resign. It is gratifying
to find that the services rendered by Mr. Daintree to the Colony in
his official capacity, and to Colonial Science generally, were so far |
recognized by the Home Authorities, that it pleased Her Majesty, on
his retirement, to confer on him the well-merited honour of C.M.G.
It was hoped by his friends that rest and change would, to some
extent at least, restore his shattered health, but notwithstanding a
residence at Mentone during the winters of 1876 and 1877, and all
that professional attention and affectionate family care could do, he
gradually sank, and shortly after reaching this country in May last,
he passed away. In a letter to a mutual friend dated Mentone,
November, 1876, Daintree wrote thus:—‘‘ Thanks to hard work and
rough food in a tropical climate, I managed to damage my liver, so

1 Report on the Cape River Diggings and the Latest Mineral Discoveries in North
Queensland. By R. Daintree. Folio, pp. 7, Map. Brisbane.

2 Report on the Gold Discoveries in the Gilbert Ranges, with Sketch Map. By R.
Daintree. Folio, Brisbane, 1869. Report on the Gilbert Ranges Goldfield, with Maps.
By R. Daintree. Folio, Brisbane, 1869.

432 Obituary—Richard Daintree, C.M.G., F-G.S.

that I am now a martyr to chronic dyspepsia; and, thanks to
sedentary employment in London, and the fog and damp of the
English climate, I managed to get congestion of the lungs, with
more or less hemorrhage several times, so that, at an age when I
ought to be availing myself of my accumulated experience in
various ways, I find myself a confirmed invalid, cut off from all
active enterprise whatever.”

A large proportion of the valuable results of Daintree’s work in
Australia were nearly lost through the wreck of the ship (on
board which he and his collections were stowed) at the Cape of
Good Hope. Fortunately, however, the cases were recovered, and
their contents supplied the material for the most exhaustive paper
yet published! on Queensland Geology. One of the chief points
there brought out was the great extent of ground occupied by rocks
of Cretaceous age in the north of Australia, for although Cretaceous
fossils had been determined some years before by Prof. M‘Coy, Mr.
Daintree appears to have been the first to point out the extent of the
beds containing them. During the last few years of his life, when
incapacitated by illness from active exertion, the microscope afforded
Mr. Daintree much enjoyment, his attention being particularly
directed to the subject of Petrology, more particularly as applied to
Queensland rocks. We are informed that at the time of his death
he had in preparation an important work on this subject.

An accomplished photographer, Mr. Daintree exhibited a fine series
of Photographs at the Edinburgh Meeting of the British Association
in 1871, and read a short paper? illustrated by them. His last
scientific communication was read to the Geological Society of
London on February 20 of this year.’

Richard Daintree was an enthusiastic man of science, and especially
devoted himself to Geology, Chemistry, and Photography; a man of
great determination and strength of character; methodical and
practical in all his habits; a genial companion, a true friend, and a
most conscientious servant of the Crown. He has unfortunately
passed from amongst us at a time when, had he retained his health,
his vast knowledge of Australian Geology would have been of
inestimable value to Science, especially to that branch to which he
had more particularly devoted himself, the origin and occurrence of
Gold. His memory will long linger in the minds of his many close
and intimate friends, and in none more than those who had the
pleasure of his acquaintance during the active years of his life, and
who shared with him some of the dangers and difficulties of ‘‘ bush
life,” which have, we fear, in a great measure tended to shorten the
career of one of the most accomplished of Australian Geologists.

R. E., Jun.

1 Notes on the Geology of Queensland. By R. Daintree, F.G.S. With an
Appendix, containing Descriptions of the Fossils, by R. Etheridge, F.R.S., and W.
Carruthers, F.R.S. ° Quart. Journ. Geol. Soc. 1872, vol. xxvui. pp. 271- 360, Maps
and Plates, etc.

2 On the General Geology of Queensland. Brit. Assoc. Report for 1871, Bh 24R- 95.

3 “ Notes on Certain Modes of Occurrence of Gold in Australia.”

| GEOL.MAG. 1878. New SERIES. DECADE II. VOL.V. PLATE XI.
a Fig 1

Seamer

1G ike nat

Brachypyge carbonis. HWoodward, 1878.
e/e

THE

GHOLOGICAL MAGAZINE.

NEW SERIES. DECADE II. VOL. V.
No. X—OCTOBER, 1878.

OF EG esNAsis: | Aves eek Cees.

—=

I.—Drscovery oF THE Rematns or A Fosstz Cras (Decapopa-
BracHyuRA) IN THE CoaL-MEAsuRES oF THE Environs oF
Mons, Brenerum.

By Henry Woopwarp, LI.D., F.R.S., F.G.S., ete.,
of the British Museum.

(PLATE XI.)

A. PREUDHOMME DE BORRE, the Conservator of the
M. Royal Museum of Natural History in Brussels, having
received, some time since, from M. Persenaire, the impression and
counterpart of the abdomen of a small Crustacean discovered in the
Coal-shales at the ‘ Belle-et-Bonne’ Colliery, near Mons, he submitted
it to the inspection of the Entomological Society of Brussels at their
Monthly Meeting on 5th June, 1875.

After carefully examining these impressions, Professor L. G. de
Koninck stated that in his opinion they certainly belonged to an
entirely new genus and to a species of Crustacean not hitherto known
from the Coal-measures. By his kindness, the fossil was afterwards
transmitted to me for examination, and, at his request, I drew up
the subjoined account of this very interesting and unique specimen,
which has since been communicated by Professor de Koninck to the
Royal Academy of Belgium.’

The Coal-measures have long been celebrated for the wonderful
assemblage of organic remains which they have yielded, an assem-
blage none the less interesting from the fact that some of these
remains represent groups of animals which belonged to the Paleozoic
period, and whose last representatives are found in the Carboniferous
formation, such as the genera Phuillipsia and Eurypterus; while
others, on the contrary, belong to the Neozoic period, and make their
first appearance on this horizon.

Among these latter we may mention the first appearance of
Amphibia ; of Scorpions and Spiders; of Myriapods; of Orthoptera
(Locustidee, Mantide, Blattide) ; of Neuroptera; and the first
Lobster-like Crustacean (Anthrapalemon).

Other forms, characterizing at the same time the Paleozoic and
the Neozoic periods, are equally well represented in the Carboniferous
formation. Of these, the genera Prestwichia and Bellinurus may be

1 See the Bulletins de P Académie Royal de Belgique, 2me série, tome xly. No. 4,
Avril, 1878.
DECADE Il.—VOL. V.—NO. X. i 28

434 Dr. H. Woodward—Discovery of a Fossil Crab—

cited as examples. These Limuloid Crustaceans have their earliest
representative (Neolimulus) in the Upper Silurian shales of Lanark-
shire, whilst their latest representative (Limulus) is actually found
living in the seas around China and Japan and on the Hast Coast of
North America at the present day.

Professor L. G. de Koninck has just drawn my attention to a
remarkable fossil obtained by M. Persenaire from the Coal-shales of
the ‘ Belle-et-Bonne’ Colliery, near Mons, Belgium.

This specimen, so kindly placed in my hands for examination by
M. de Koninck, represents, without doubt, the abdomen of a female
Crab (Decapoda-Brachyura). Unfortunately no other part of the
animal has been discovered; we can only, therefore, conjecture
what its general form may have been from a consideration of the
portion preserved.

The specimen, which is 12 millimétres in length, is preserved
upon the surface of a fragment of Coal-shale associated with the
impressions of Neuropteris heterophylla and Alethopteris lonchitidis.

The abdomen is as nearly as possible perfect, and upon the surface
of the two pieces of shale, which correspond, we see clearly the
impression and counterpart of the fossil.

Notwithstanding the small size of the specimen, M. Rutot, C.E.,
has executed, under the direction of M. L. G. de Koninck, an
admirable figure, greatly enlarged, showing clearly all the salient
points of the fossil. By the kindness of the Council of the Royal
Academy, I am enabled to reproduce this excellent figure (see
Plate XI.).

As in other short-tailed Decapod-Crustacea, the abdomen is seen to
consist of seven segments more or less completely ankylosed together,
as in the Leucosiade. Unfortunately the external surface of the
central axis of the abdomen is wanting, but the divisions, strongly
indicated by raised lines, plainly show the area of each segment of
the median portion of the abdomen, and also clearly separate the
central axis from the widely expanded lateral border.

The general form of the abdomen is oval save at its proximal
border, where it was attached to the cephalothorax (Pl. XI. Fig. 1,
ab). This articular border (ab) measures 5 mm. in breadth, and
was evidently inserted under the posterior margin of the carapace to
about the depth of one millimétre.

The two angles of the articular margin (a, a) project slightly
beyond the rest of the border, and evidently furnished two strong
points of attachment with the abdomen.

The 1st segment, of which the articular border forms a part, is in
the form of a trapezium, having its broadest border directed forwards
and measuring 5 mm. in breadth, whereas the posterior border only
measures 3} mm.; the lateral borders of the segment are greatly
inclined.

The central part of this segment bears two tubercles placed
symmetrically, one on either side of the mesial line, whilst three
small puncte are placed near the centre of the posterior border.

The axial or central part of the 2nd, 8rd, 4th, Sth, and 6th

in the Coal-Measures of Belgium. 435

segments are nearly the same in form, but they diminish insensibly
from the 2nd to the 6th segment. From 34 mm. in breadth by 1} mm.
in length, they gradually “decrease to 2 mm. in breadth and 1 mm. in
length. Hach segment bears three puncte disposed symmetrically
near the centre and in close proximity to the posterior border, with
the exception of the 7th, or terminal, segment, which is ornamented
with a single small oval tubercle, situated on the median line and
near the anterior border.

The 7th segment is three and a half times as long as the 6th, or
preceding, segment; it spreads out in a fan-shaped form, being only
2 mm. broad at its anterior border, whilst it expands posteriorly to a
breadth of 6 mm. at its lower extremity.

The lateral or epimeral border of the segments is about 34 mm. in
breadth ; its surface ornamentation has been preserved, and evidently
once extended over the central axis also, but has been removed from
this part of the specimen probably when separating it from its
counterpart.

The divisions existing between each segment are clearly marked,
and are continued to the lateral border of the abdomen in the
form of a series of slightly raised lines, each marked by a row of
small tubercles. The outer border of each segment is slightly
concave or emarginated.

A raised line, having its origin at the side of the central axis of
each abdominal segment, traverses the epimeral portion of the 2nd,
3rd, 4th, 5th, and 6th segments, forming a slightly sigmoidal curve,
inclining downwards and uniting with the posterior margin of each
segment near its border.

Two lines, nearly parallel, and corresponding in contour with the
curvature of the exterior border of the abdomen, pass across the
lateral portion of each segment between the Ist and the 7th, when
they unite to form the limit of the central or axial part of the last
segment; by these lines the lateral border of the abdomen is divided
into three parts sloping fanwise towards the exterior.

With the aid of a magnifying glass the surface of the border of the
abdomen is seen to be ornamented with fine granulations.

From the general conformation of the segments, and after careful
comparison with numerous specimens, we are led to the conclusion
that the fossil under consideration represents the abdomen of a female
Brachyuran Decapod, and not the thoracico-abdominal seements of a
Limuloid Crustacean such as Bellinurus or Prestwichia, with the form
and segmentation of which it cannot be confounded. Nor are we
acquainted with any Arachnide which presents a form of abdomen
similar to this fossil. Nevertheless, in comparing this interesting
specimen with the abdomen of numerous modern short-tailed Deca
pods, we cannot but observe that it presents many well-marked and
distinctive peculiarities, both in the form of the segments themselves
and also in their ornamentation.

Having lately received from Mr. J. McMurtrie several fragments
of a new Crustacean discovered by him in the Radstock Cra field,
near Bristol, and also some other portions which I have reason to

436 WI. EB. Rigauz—The Brachiopoda of the Boulonnais.

believe may have likewise belonged to a Brachyuran Decapod from
the Pendleton Colliery, near Manchester, I have felt greater confi-
dence in the determination of the Belgian fossil, and in considering
it as constituting the abdomen of a true crab.

The most ancient short-tailed crab hitherto known is the Pale-
machus longipes from the (Forest Marble) Great Oolite, Malmesbury,
Wiltshire, which I described in 1866.1

The discovery of this fossil, therefore, removes the origin of the
Decapoda-Brachyura to an epoch in geological time far anterior to
that hitherto recorded, and serves to show well how little reliance
can be placed upon merely negative evidence.

In the absence of other remains which might serve to complete
our knowledge of the animal we have ventured to describe, it would
be premature to attempt to show its affinities with any existing form
or to give it a name indicative of its relationship. I prefer, therefore,
to designate it as Brachypyge carbonis, for in the event of the dis-
covery of more complete remains which would enable us satis-
factorily to determine the modern representatives of this interesting
species, the name (if calculated to mislead) would of necessity at
once become a burden to synonymy.

EXPLANATION OF PLATE XI.

Brachypyge carbonis, H. Woodw. From the Coal-measures, ‘ Belle-et-Bonne’
Colliery, near Mons, Belgium.
Fic. 1.—Figure enlarged ten times. -| Fre. 2.—Figure of the natural size.

IJ.—Tuer Fosstn Bracuiopopa oF THE LowER BovLoNNAIS.

HE following carefully and elaborately prepared list of the fossil
Brachiopoda of the Lower Boulonnais has been forwarded to
the Editor for publication by his esteemed friend and frequent con-
tributor Thomas Davidson, Esq., F.R.S., who writes as follows :—
“At my request M. H. Rigaux (51, Grande Rue, Boulogne-sur-mer,
France) has been engaged for more than two years in drawing up
a complete summary of all the Brachiopoda that are to be found in
the various formations composing the Lower Boulonnais.

“This list is of great importance as so many of the beds correspond
completely with our own, and are extremely rich in a paleonto-
logical point of view. Tomas Davipson.

‘3, Leorpotp Roan, Brieuton, 7th August, 1878.”

List or Foss Bracuiopopa FoUND IN THE LowrrR BovLonnais.

By Monsieur E. Rreavx.
DEVONIAN.

Terebratula sacculus, Mart. Very common in the shales of Beaulieu,
scarce in the Ferques limestone.

Spirigera concentrica, D’Orb. Very common in the highest beds of
the Ferques limestone; Blacourt, Beaulieu.

Spirigera Pelapayensis, D’Orb. Rather common in the shaly beds
over the Blacourt limestone in the Cédule quarry, scarcer in the
Ferques limestone at Blacourt.

1 Quart. Journ. Geol. Soc. vol. xxi. p. 494.

M. E. Rigaue—The Brachiopoda of the Boulonnais. 487

Spirigera Davidsont, R. Is found only in the shales over the
Blacourt limestone at Couderousse.

Spirifer Verneuilli, Murch. Very common in all the Devonian shales
and limestones, offers several varieties; in the limestones the
wings are short, and the beak strongly incurved; in the shaly
beds the wings are very long, the area wide, and the beak not
recurved ; the variety Archiachi is found only in the higher beds
of the Ferques limestone.

Spirifer Bouchardi, Murch. This species is found under varying
forms at three levels; in the shales of the Cédule quarry it is
depressed, larger, and the two ribs that limit the sinus are not so
strong as in the second variety which is common at Couderousse ;
the typical form figured by Murchison is only found in a par-
ticular bed of the Ferques limestone.

Spirifer Urii, Dav. Scarce, Beaulieu shales.

Spirifer Sauvagei, R. Scarce; is found in the Beaulieu shales with
the two following species in the level of Stérept. elegans.

Spirifer Legayi, R. Common at Beaulieu.

Spirifer Barroisi, n. sp. Scarce, Beaulieu. This species is very
near to Sp. Legayi, from which it differs by a less transverse
form, a narrower sinus, lamine of growth not so strong, but
closer and more numerous.

Spirifer undiferus, Schn. Very scarce, Beaulieu.

Cyrtina heteroclyta, Dav. Rather common at the lowest part of the
Beaulieu shales, does not seem to go higher than the level of
Strept. Bouchardi.

Cyrtina Demarlit, Dav. Scarce, Beaulieu shales.

Spirigerina reticularis, D’Orb. This is a very common species, and
offers several varieties; Ferques, Blacourt, Beaulieu.

Spirigerina aspera, M‘Coy. Common, Ferques.

Spirigerina longispina, Bouch. Is only found in the sandy limestone
band over the Ferques limestone.

Ehynchonella Lummatoniensis, Dav. Occurs in the Beaulieu shales.

Rhynchonella acuminata, Mart. A variety of this species is very
abundant in the shales with Sirept. elegans; Beaulieu.

Rhynchonella Boloniensis, D’Orb. Common in the upper part of the
Ferques limestone, and in the sandy limestone over it; Beaulieu.

Pentamerus brevirostris, Phil. Is found commonly in a small calca-
reous band below the Ferques limestone.

Orthis striatula, DPOrb. Common everywhere, Ferques, Beaulieu.

Orthis Deshayesii, Bouch. Very common in the level of Strepi.
Bouchard.

Orthis Dumontiana, Vern. Common in the same bed.

Orthis Eifeliensis, Sch. Scarce, is found with Pent. brevirostris at
Beaulieu.

Streptorhynchus Devonicus, Dav. Common at the highest part of the
Ferques limestone.

Streptorhynchus elegans, Bouch. Very common, distinguishes a
particular level in the Beaulieu shales.

Streptorhynchus Bouchardi, R. Very common, Beaulieu shales.

438 WU. E. Rigaux—The Brachiopoda of the Boulonnais.

Strophomena latissima, Bouch. Very common in the sandy band
over the Ferques limestone.

Sirophomena Gosseletii, R. Rather scarce, Beaulieu shales.

Leptena Dutertrii, Murch. Very common in the highest part of the
Ferques limestone.

Leptena Ferquensis, R. Very common, Beaulieu shales.

Leptena Cedule, R. Very common, lowest part of the Beaulieu
shales.

Leptena Fischeri, Vern. Common, Beaulieu shales.

Chonetes armata, Bouch. Very common over the Ferques limestone.

Strophalosia productoides, King. Very scarce, Ferques, Beaulieu.

Productus subaculeatus, Murch. Common in every bed, Ferques.

CaRBONIFEROUS LIMESTONE.

Terebratula hastata, Sow. 'This species is found in great numbers
in a bed from the highest part of the white limestone, Napoleon
quarry.

Athyris Roissyi, M‘Coy. This species has been found by Mr.
Dutertre at Hardinghem in the Black quarry, which is now full
of water.

Spirifer laminosus, M‘Coy. Occurs sparingly in the white limestone
at Hydrequent.

Spirifer glaber, Mart. Very common in the bed with T. hastata.

Productus Cora, D’Orb. This species is found in the lower limestone
of the La Cote and Malassise quarries ; it is more common in the
Haut-bane limestone.

Productus semireticulatus, Mart. Common in the bed with Tr.
hastata, was also formerly found in the Black quarry.

Productus giganteus, Mart. There oceur in a small quarry near
Ferques, and in another near Hardinghem, crushed specimens of
a large Productus which Mr. Gosselet refers to this species.

BaTHONIAN.

Terebratula mazillata, Sow. ‘This species occurs sparingly in the
Great Oolite at Hydrequent and in the Cornbrash, Le Wast.

Terebratula submaxillata, Dav. This species is confined within the
lower beds of the Great Oolite; Hydrequent.

Terebratula globata, Sow. Very common in the lower part of the
Great Oolite at Hydrequent, is found also in the Marquise Oolite ;
the variety Fleischeri, Opp., occurs unfrequently in the Cornbrash
at Le Wast.

Terebratula intermedia, Sow. Very common in the Cornbrash ; Le
Wast, Lenlinghem.

Terebratula coarctata, Park. Very scarce, Cornbrash, Le Wast.

Terebratula hemispherica, Sow. I have found a single specimen in
the Cornbrash ; Le Wast.

Waldheimia obovata, Sow. Very common; the variety Siddingto-
nensis in the Great Oolite at Hydrequent; the varieties perobovata,
subobovata and Stiltonensis in the Cornbrash at Le Wast.

Waldheimia lagenalis, Schl. Common in the Cornbrash with the
variety sublagenalis.

M. E. Rigauz—The Brachiopoda of the Boulonnais. 489

Waldheimia cardium, Lam. Very scarce, Cornbrash; Le Wast,
Lenlinghem.

Rhynchonella concinna, Sow. Common in the Hydrequent limestone.

Rhynchonella Hopkinsi, M‘Coy. Very common in the Great Oolite of
Marquise; a single specimen from the Cornbrash at Le Wast.

Rhynchonella elegantula, Bouch. Very common in the marly lime-
stone between the Cornbrash and Great Oolite; Le Wast,
Marquise.

Rhynchonella Badensis, Opp. Very common in the Cornbrash, Le
Wast; a single specimen from Hydrequent, in the lower part of
the Great Oolite.

Rhynchonella Moriert, Dav. Very common in the Cornbrash; Le
Wast, Marquise.

Rhynchonella varians, Sow. var. We find in the Cornbrash at
Rinxent a small form which we refer to this species.

Oxrorp Cray AnD Lower Catc Gait.

Waldheimia umbonella, Lam. Very common at Belle; a single
specimen from the clays at Le Wast.

Rhynchonella socialis, Phill.

Rhynchonella Leedsii, Walk. 'These three species are found in the
ferruginous Oolite (Kelloway Rock), over the Cornbrash at Belle
and Alincthun.

Waldheimia impressa, Buch. Occurs in great numbers in the clays
at Le Wast; one specimen has been found in the Coral Rag
at Carly.

Terebratula insignis, Sow. Scarce in the Calcaire and Houllefort
(Elsworth rock) ; it is more common in the calcareous band over
it at Rety, and is very abundant in the Calcaire du Mont des
Boucards.

Waldheimia bucculenta, Sow. Very scarce, I have found six speci-
mens in the Calcaire du Mont des Boucards.

Rhynchonella pectunculoides, Et. Very common in the lowest beds
of the Calcaire du Mont des Boucards.

Rhynchonella myriacantha, Desl. I have found a single specimen in

- the clays at Bléquenéque.

Rhynchonella spathica, Lam. Very common in the Ter. impressa
beds; Le Wast.

CoRALLINE AND SUPRACORALLINE Beps.

Terebratula insignis, Sch. Ends in the Supracoralline Oolite at
Hesdin l’Abbé with forms which show a transition between this
species and 7’. subsella.

Terebratula subsella, Leym. Shows itself at first in the Supracoral-
line Oolite at Hesdin l’Abbé, and goes up in the Kimmeridge beds.

Terebratula globata? Sow. The Oolite of Hesdin l’Abbé contains
a biplicated Terebratula, which I cannot distinguish from our
Great Oolite globata.

Waldheimia humeralis, Rom. I have sometimes quoted this species
under the name of T. bucculenta, which I apply now to another
species at a lower level; it appears in the Coral Rag proper at

440 ME. Rigaua—the Brachiopoda of the Boulonnais.

Carly, but is more abundant in the Supracoralline Oolite of
Hesdin l’Abbé.

Rhynchonella pectunculoides, Et. This species goes up into the Coral
Rag; Carly.

Rhynchonella pinguis, Rom. This species is found in the Coral Rag,
Carly, and in the Supracoralline Oolite; Hesdin l’Abbé.

Rhynchonella inconstans, Sow. Very scarce, I have found it only in
the Grés de Questrecques, the highest Supracoralline bed.

Thecidium ornatum, Moore. Mr. Davidson first found this species
on a Ter. humeralis from the Carly Coral Rag, and since I have
obtained some other specimens, but it is rather scarce.

Kimmertper Cuay.

Lingula ovalis, Sow. This species was discovered by Mr. J. H. H.
Peyton, F.G.S., near the base of the shales in the cliffs of
Boulogne ;! it is very common. I have also found in the Portland
shales remains of a Lingula which belong probably to the same
species.

Terebratula subsella, Leym. Is rather common in the lower part of
the Kimmeridge. Cliffs of Moulin Wibert, Chatillon.

Waldheimia humeralis, Rom. I refer with doubt to this species,
some small smooth Terebratule found by Mr. Beaugrand in the
Lower Kimmeridge beds ; Moulin Wibert.

Rhynchonella pinguis, Rom. Very scarce; two or three specimens
have been found in the lowest beds in the cliff of Moulin Wibert.

PORTLANDIAN.

Discina latissima, Sow. I have found good specimens of this species
in the shales that overlie the grits with 4. gigas in the cliffs at La
Créche and Le Portel; it is rather common.

Waldheimia Boloniensis, R. 8.

Waldheimia humeralis, Rom.

Rhynchonella subvariabilis, Dav. These three. very scarce species are
found in the Middle Portland beds with Ostrea expansa; Tour
Croy, Alpreck.

Lower GREENSAND.

Waldheimia pseudojurensis, Leym.

Rhynchonella Gibbsiana, Sow. These two very scarce species have
been found by Mr. Bouchard in the’ sands under the Gault with —
Amm. mammillaris ; Locquinghem.

GavLt.
Terebratula prelonga, Sow. Occurs in the phosphatic bed under
the Gault; Fiennes, Lottinghem.
Rhynchonella Gibbsiana, Sow. In phosphatic nodules, Fiennes.
Rhynchonella lineolata, Phill. I have some internal casts from
Fiennes which seem to belong to this species.
Cuatk Mart.
Magas Geinitzti, Schl. This species has been found by Mr. Barrois
at Licques and at Blanez.
1 See Gzon. Mac., 1873, Vol. X. p. 574, with a woodcut figure.

M. E. Rigauz—The Brachiopoda of the Boulonnas.

441

Terebratella truncata, Sow. We refer to this species some small
specimens which occur rarely in the Cement Chalk at Neufchatel,
but Mr. Barrois looks upon them as belonging to a new species.

Kingena lima, Dav.
Terebratulina striata, Wahl.
Terebratulina rigida, Sow.

DEVONIAN.

CARBON-
IFEROUS.

PALZOZOIC BRACHIOPODA
FOUND
IN THE LOWER BOULONNAIS.

Blacourt Limestone.

Beaulieu Shales.

Spirig, Davidsont
Shales.
Strept. Bouchardt
Clay.

Marl.

Pent. breviros-
trvs Limestone.

Strept. elegans

Ferques Limestone.

Sandy Limestone.

Lower Limestone.

Upper Limestone.

Terebratula saccitlats, Mart. cscs
LEAL ONE

Spirigera concentrica, D’Orb.........
Pelapayensts, D’Orb.
Davidsont, Re cvccsses. ass
DROPS fy IOP OND), crrccceceteccerecee

Spirifer Vermewillt, Murch. veescescecsseeeeee x

SORIA, 1 covrooptercreetrces ecpcereceD
EU OR, 6, SDs ckicerccectomn ox
UNALEVUS, SCH. ..rv0r0
laminosus, M ‘Coy
FOLIPUCT AEN lata ecteee rte ere ee
Cyrtinmanfeteroclza, Dania \ ernie x
DEOL OUC ep te
Spirigerina reticularis, D’Orb. ...
Loneispind, BOUCH. «reser
OGRE AE, WUT CONS crreeccnnceconc eterereroneres
Rhynchonella Lummatoniensis, Dav. ....
acuminata, Matt......
Boloniensis, D’Orb. ;
Pentamerus brevirostvis, Pil. essere
Oxnthisesinzarilo WO iba ee x
DesHiayes7t, WRo) Veeccercsse
Dumontiana, Vern. .
SEGSHOT ISIS, (SONS | cereerere a
Streptorhynchus Devonicus, Dave .rvee..-.
CLETATS WB OUCH eset
Bouchardi, R. .... a
Strophomena latissima, BOUChy ce...
GOSSCIETID Rape eee eee
Leptena Dutertrit, Murch.
Ferquensis, R. ..
(COUM a, VR mrcere oe
Bischerd Nietiseese san
Productus subaculeatus, Murch. .ereccsvsceeere- x
Gora Oi@ rb yee
semireticulatus, Mart.
SG IAOUTUGOIS.ceeveccceentcreratrececesecxc oo
Strophalosia productotdes, King...
Chonetes armata, Bouch, reessscssssssesessreees

tal

x

MS BS VBS jh 2S

ta

442

DSTRIBUTION OF
OOLITIC BRACHIOPODA
IN THE
LOWER BOULONNAIS.

Lower Great
Oolite.
Upper Great

Oolite.

Cornbrash.

Kelloway Rock.

Oxford Clay,

(PLM. GLH, SOW seoctcorcereereeeepeecenssrenneee
Discina latissima, SOW. vw.» i
Thecidium ornatum, Moore
Terebratula maxillata, Sow. .... a
submaxtllata, Dav. cscs x
ZNLEVMLEALA, SOW. srsrsessssvrsssseree
INSUGNIS, SCHe w..
Slobata, SOW. wus.
hemispherica, Sow. By
COAT CLALO MEAN coe
SUSE ON ee
Boloniensis, R. S.
Waldheimia lagenalis, Sch. ....
umbonella, Lam. _
QUGUOTO MS OW ema
Succulenta, SOW. sess
zmpressa, Buch. .........
humeralis, Rom. .......
Cardiumt, LAM. verve a
Rhynchonella concinma, SOW.- sreccseeereeee x
LLophimst, MSCOY eescsssssecsseseens
elegantula, Bouch..... a
Badensiss Opie tes
MWY G0, IDES exon am coormcernonee
varians, (var.) ....
Leedsit, Walk.
socialis, Phil. ......... A
GROLLAL, MUBSIDG coeccerrcenempirces
meyrtacantha, Desh. srs
pectunculoides, Et. ...
pinguis, Rom. .....
znconstans, Sow. .«. :
SUbvariabilis, Dav. cesses

DISTRIBUTION OF
CRETACEOUS BRACHIOPODA
IN THE
LOWER BOULONNAIS.

MOROS GREE, (SOM ccomesmmccectococncccnnoe ee
Terebratella truncata, SOW...
Kingena lima, Dare crv
Terebratulina striata, Wahl.
VIgtda, SOW. or. ee
Terebratula biplicata, SOW. sresssssssssssessseeeeessien
POCO, SOW vivoemeromczco,
semiglobosa, Sow. ..
squamosa, Mant.
Sulcifera, MOY. ress. =
Waldhetmia pseudopurensis, Ley. ..sserse0
Rhynchonella Gibbsiana, SOW. sw... roe
lineolata, Phill. .......
Martini, Mant. ...
Grasiana, D’Orb... i
Marntelliand, SOW. cress

mM

Lower
Greensand.

mR

Lower Grit.

Coralline Lime-
stone.

M. E. Rigauw—The Brachiopoda of the Boulonnais.

Supracoralline.

Kimmeridge Clay.

*

Gault.

Upper
Greensand.

oh mM MM | Chalk Marl.

Cita

K

Portlandian.

William Davies—Note on Pleistocene Mammalia. 443

Terebratula squammosa, Mant. These four species are very common
in the Chalk Marl at Blanez and Neufchatel.

Terebratula biplicata, Sow. Occurs in the Glauconitic bed above the
Gault; Blanez.

Terebratula sulcifera, Morris. Seems to be very scarce; J know
only two specimens which Prof. Gosselet has had the kindness to
send me; Blanez.

Terebratula semiglobosa, Sow.

Rhynchonella Martini, Mant.

Rhynchonella Grasiana, D’Orb.

Ehynchonella Mantelliana, Sow. These four species are very common
in the Chalk Marl at Blanez and Neufchatel.

IlI.—Suprrementary Nore to “ Puiristocene Mammats DrepGEp
oFF THE Hastern Coast.”?}
By Wituram Daviess, F.GS.,
of the British Museum.
(PLATE XII.)

HE late Dr. Falconer figured in the “Fauna Antiqua Sivalensis,”’
a fine lower jaw of an adult Hlephas primigenius, preserved in
the National Collection, and of which he gives two views, the first
as seen from above, the second a side view; and in the descriptions
of the plates in the above work given in his “ Paleontological
Memoirs,” vol. i. p. 439, occurs the following note regarding it:
“Plate xiii. A. fig. 3.—£. primigenius. English fossil specimen,
with two last true molars on either side. In the last left molar there
are eighteen plates in 7-7 inches. The jaw has a short beak, and
one inner mentary foramen on either side. In this, as in figs. 1 and
2, representing the jaw at different ages, it is to be noted that the
opposite lines of molars are more or less convergent instead of being

parallel, or nearly so, as laid down by Cuvier.

“Extreme length of jaw, 23:6 in. Divergence of rami behind,
21:3 in. Height at alveolus, 7-2 in. Greatest width of jaw, 6:3 in.
Breadth of condyle, 10:3 in., width of last molar, 2:8 in.”

To the above description may be added, that although the ascend-
ing rami are well preserved, the condyles and coronoids on each
side are wanting.

Besides the fact that it is a dredged specimen, which is evident
from the marine exuvie still adhering to it, and that Dr. Falconer
had selected it for illustration as a type of the mandible of a mature
adult animal of the above species, not anything was known respect-
ing its history, or whence it came, by the present officials of the
Paleontological Department; nor beyond the statement that it is an
“‘ English fossil specimen” does Dr. Falconer throw any light upon
its history, if he ever knew it. But some time ago, looking through
a volume of the “Magazine of Natural History,” edited by Mr.
Edward Charlesworth, F.G.S., I found a woodcut of the fossil, and
a short notice regarding it by the editor, both of which we here
reproduce.

“The fossil elephant’s jaw represented in the accompanying figure

1 See Gzou. Mac., 1878, Decade II. Vol. V. p. 97.

444 William Davies—Note on Pleistocene Mammalia.

(No. 40), was obtained by a Dover fisherman in 1837, while dredg-
ing off the Dogger Bank; and after having been offered for sale to
the British Museum and other Metropolitan institutions, was pur-
chased by Mr. G. B. Sowerby, in whose possession it has since
remained. It is decidedly the finest relic of the kind that I have
seen ; and the very faithful representation which I am enabled to
publish of it is due to the skill of Mr. G. B. Sowerby, jun., by
whom the drawing on wood was executed.”'—Mag. of Nat. Hist.
July, 1889, vol. iii. pp. 8347-8. However, the specimen was ulti-
mately purchased for the National Collection on the recommendation
of Mr. C. Keenig, the then Keeper of the Geological Department,
soon after the publication of Mr. Charlesworth’s notice.

The special interest attached to the jaw, apart from its importance
as having been selected as a type specimen by so acute an observer
as Dr. Falconer, is the locality whence it has been derived, and the
additional confirmation it gives of the typical character of the
remains of the Mammoth obtained from the Dogger Bank, as de-
scribed by me in a notice of the almost unique collection from this
locality made by Mr. J. J. Owles, of Yarmouth, in the March
Number of the present volume of the Grotocicat MaGazinE (p. 97).
Thus it appears, on the evidence before us, that Elephas primigenius
is the only species found on the Dogger Bank, whereas the three
species E. primigenius, E. antiquus, and EH. meridionalis, all occur in
the Forest-bed series along the Norfolk coast. Of these the Hlephas
antiquus, according to Dr. Falconer, would seem to be the most
abundant, for he says: “Of the two thousand Elephant grinders,
which Mr. (Samuel) Woodward estimates to have been dredged up
within thirteen years, from the oyster-bed near Happisburgh, I be-
lieve that by far the largest number belonged to this species. The
next in point of number, are those of the true Mammoth from the
wide-spread drift and gravel-beds. Teeth of H. meridionalis are
much less frequent.”—(‘‘ Falconer’s Paleontological Memoirs,” vol.
li. p. 204.)

Considering the interest attached to this locality, and the number
of fossils it has yielded to the dredge, the records regarding them
are few. Prof. Owen, in his “ British Fossil Mammals,” has given
a most extensive summary, both of the remains found, and the
localities whence fossil elephants have been obtained, but has no
notice of this jaw, unless the following quotation refers to it: “A
fine lower jaw of a young Mammoth, in the possession of Mr. G. B.
Sowerby, was thus dredged up off the Dogger Bank; and a femur
and portion of a large tusk were raised from twenty-five fathoms
at low water, midway between Yarmouth and the Dutch coast.” ?
But when the above was published, the mandible noticed by Charles-
worth had been long in the British Museum, and his engraving of it
had been known for some years.

1 Mr. Charlesworth subsequently used the woodcut to illustrate the wrapper of his
“London Geological Journal.” The accompanying figure, Plate XIIJ., is a careful
reproduction of the original by Miss G. M. Woodward.

* Brit. Foss. Mamm. and Birds, 1846, p. 259.

GEOL. Mac. 1878. NEw SERIES. Dec. II. Vou. V. Pl. XII.

Lower Jaw of Mammoth,

Llephas primigenius, Blum.

Dredged off the Dogger Bank, 1837.

The Original preserved tn the British Museum.

G. M, Woodward, delt. S. Austin and Sons, imp.

Joseph Nolan—Volcanic District of Slieve Gullion. 445

IV.—Own toe Ancrent Voucanic District oF SLIEVE GULLION.!

By Josrru Noxan, M.R.I.A., etc.,
of H. M. Geological Survey of Ireland.

T seems to be one of the chief objects of the British Association
for the Advancement of Science in changing the place of meeting
every year, to bring more prominently before the members of its
respective sections such points of interest in their own department
of Science as are afforded by the various localities. In accordance
with this principle, I beg to lay before you some observations con-
cerning the geology of a district not more distant than about two
hours’ railway journey from Dublin, which will, I trust, be of
peculiar interest on the present occasion. The district I refer to is
the hill country north of Dundalk, of which Slieve Gullion forms
the most prominent feature. This mountain is a somewhat isolated
mass, attaining an elevation of about 1900 feet, and is situated to
the north-west of the hilly and picturesque country lying between
the bays of Dundalk and Carlingford, or due west of the more
remarkable group of the Mourne Mountains. The rocks of which
it is mainly composed are of a plutonic character, and rise through
granite, the south-western termination of the tract of that rock
which extends from this in a north-easterly direction to Slieve
Croob, a distance of about thirty miles. This granite is not in the
main intrusive, but is rather the result of the metamorphism of the
Lower Silurian sedimentary rocks. The transitions from the latter
into the former may be observed in many places—the Silurian rocks
becoming indurated, then schistose and slightly micacised, passing
into crystalline gneiss, which frequently loses its foliation and passes
into granite. In other places the transitions are somewhat less
gradual, chemical differences in the composition of the rocks having
probably favoured the readier conversion into granite, while in others
again, no transition whatever is perceptible, and the rock seems in
those parts to be intrusive, the more highly fused portions having been
forced up and thrust through the upper parts of the sedimentary rocks,
or those least affected by metamorphosing agencies. A remarkable
instance of the kind may be seen at Mullaghbane, some four miles
west of Slieve Gullion, where a tongue from the granite cuts through
both the Silurian sedimentary rocks and an old igneous rock (diorite)
associated with them; while in the same neighbourhood, transitions
from the indurated sedimentary rocks into the main mass of the granite
are exceedingly well marked, and even hand specimens exhibiting
these changes may be procured.

Similar phenomena were also noticed on the eastern side of the
mountain, of which my colleague, Mr. Egan, gives many instances.
(See Geological Survey Explanation to accompany Sheet 59). Thus,
at Camlough Mountain, he observes that, “the granite contains

1 Read before the British Association for the Advancement of Science, Dublin,
(Section C.), August 15, 1878.

446 Joseph Nolan—Volcanic District of Slieve Gullion.

gneissose bands merging into harder and more solid granite,” and in
the hill east of this mountain, where the granite is similar, though
in places nearly losing its mica, there is an unmistakable passage
from micaceous schists into foliated granite” (abid. p. 14).

The age of formation of this, called the Newry granite, cannot be
determined, but there is strong reason for believing that it took
place prior to the Upper Silurian period, as suggested by Prof. Hull.’
The basal conglomerates of that system contain pebbles and boulders
of granite, as well as of schist and gneiss, and as granite fragments
are not met with, in Ireland at least, in formations older than the
Lower Silurian, we may fairly assume that it was formed with the
schist and gneiss, the eruptive and metamorphic granites being but
varied results of the same plutonic action.

Micaceous Dolerite.—Hruptive through the granite is a coarsely
crystalline rock of massive character, forming most of the northern
and western parts of the mountain. It has the usual characteristic ap-
pearances of dolerite, having a rude prismatic structure and weather-
ing in globular exfoliating masses. It consists of augite and plagio-
clase felspar, of which there may be more than one variety, those
most largely developed being labradorite. In addition, it has a
bronze to black-coloured mica, sometimes in considerable quantity,
a large proportion of magnetite, olivine, and a green structureless
mineral that is probably epidote.

Elwanite or quartz porphyry.—Associated with this dolerite, and
forming the remaining part of the mountain, is a granitoid rock
consisting chiefly of orthoclase felspar with free silica, seldom de-
veloped into well-formed crystals, a little mica, and, usually, some
hornblende. This rock is seen in many places to penetrate the
micaceous dolerite, and is therefore probably older, though as the
dolerite also, though rarely, sends veins into the elvanite, it is
most likely that both were protruded about the same time. To
the north-west, this elvanite composes the remarkable ridge of hills
that partly inclose the mountain on the north, west, and south.
At half the extent of its course, at Cashel Lough, it changes gradually
from a granitoidal rock to one having a finer grained or compact
base, and containing double pyramidal crystals of quartz with felspar,
thus becoming a highly silicated or quartzose felstone porphyry.

Volcanic Agglomerate.—Simultaneously with this change in the
elvanite, suggesting conditions of less intense heat and pressure, a
fragmental rock of most remarkable character makes its appearance.
It is here entirely composed of granite pieces, and might indeed be
taken for a disintegrating portion of that rock, but that, on exami-
nation, the base is found to present a mechanical and not a crystalline
structure. This conclusion is confirmed on following the ridge
farther south, where, in the neighbourhood of Forkill, the associated
fragmental rock occupies a large area, and though still mainly
composed of granite, yet contains several fragments of other rocks,
all of which, however, are of local origin. Eastward of Forkill,

1 See Physical Geology and Geography of Ireland, p. 141, note.

Joseph Nolan—Volcanic District of Slieve Gullion, 447

patches of it are found in many places over the igneous rock, but
slate fragments are here prevalent, till, at the termination of the
ridge, at Slievenabolea, they almost form the entire mass, like the
granite at the other end, the lower portions, however, passing into
the felstone by such insensible gradation that no line of demarcation
is possible.

That this rock is of a volcanic character, somewhat analogous to
volcanic agglomerate, we can scarcely entertain a doubt. Never-
theless, it differs widely from the usual type of that rock, as it is,
except in the deepest portions, almost altogether composed of pieces
of non-volcanic rocks, these fragments being the pre-existing crust
through which the igneous mass was protruded, and varying ac-
cordingly—egranitic agglomerate prevailing in those portions that
were occupied by that rock—a mixture of slate and granite about
the junction of these formations, and slate fragments almost exclu-
sively in the Silurian district to the south-east. It is impossible to
account for these phenomena by supposing that we have here the
result of an eruption of an ordinary character where lava or scoriz
is ejected, as, if that were the case, some fragments at least of
these products would occur in the agglomerate, if, indeed, as
usually happens, they did not compose the entire mass. Lava
or scoriz, therefore, could not have been ejected, and the eruption
must have been entirely of an aériform character. The theory
which Professor Judd proposes to account for the formation of
vast craters, such as those of the lakes Bolsena and Bracciano in
Central Italy, seems to afford a probable explanation of the facts in
this case. Where the igneous mass rises through a vertical fissure,
the initial eruptions, due to a mere “local disengagement of vapour,”
are, comparatively speaking, moderate in their effects, and followed
by others sometimes lasting for lengthened periods, as fresh ac-
cessions of lava, charged with elastic gases, are continually welling
upward, owing to diminished pressure; but when, as in the case of
intrusive sheets, the lava is projected in a horizontal or nearly hori-
zontal fissure from the volcanic focus, there is a tension exerted on
the overlying rocks through a far larger area, which being at length
overcome, produces a tremendous and widespread explosion, but of
a very temporary character, there being no deep portions to furnish
fresh supplies. That in the district now described, eruptive rock was
projected in some such manner seems highly probable, both from its
position, as a dyke-like protrusion from the igneous mass of Slieve
Gullion, and the disposition of the agglomerate. This latter is
associated with it for seven miles of its course, its volcanic character
being most evident at the eastern end of the huge dyke, where we
may suppose it approached somewhat nearer the surface of the
ground, while about Cashel Lough, close to where it disappears, it is
scarcely distinguishable from the adjacent granite, the intumescent
mass having been here more deeply seated, and in consequence no
further result produced than a fissuring and partial dislocation of the
overlying crust.

While, therefore, the elastic forces appear to have been sufficient

448 Joseph Nolan—Volcanic District of Slieve Gullion.

to produce aériform explosions and the shattering and trituration
of the superincumbent rocks, they do not appear to have been
powerful enough to raise the igneous mass sufficiently near the
surface to produce lava or scoriz. This was probably due to the
operation of two causes, one of which I have already referred to—the
sudden consolidation of the crystalline magma on losing its inter-
stitial fluids—the other, and perhaps principal cause, the immense
weight and volume of the displaced materials. To this latter cause
Mr. Scrope refers the formation of fragmental rocks in the Upper
Hifel, very similar to those just described. These, he informs us, are
“principally, and in some. instances almost entirely, composed of
broken greywacké slate and sandstone, more or less affected by heat,
and pulverized. . . . There is an appearance as if the volcanic energy
had been damped and impeded by the mass of transition and
secondary strata which it had to pierce, and perhaps by the fragile
nature of the greywacké slate, which, shattered and pulverized by
the first few aériform explosions of every eruption, would be likely
to accumulate in great volume above and within the vent, and stifle
its further activity.”— (Volcanos, p. 376, et seq.)

Besides the felspathic rock mainly associated with the agglomerate,
there are others of a basic character, chiefly dolerites and melaphyres.
These usually occur as bosses and protrusions through the fel-
spathic rocks, and are generally tuffose at the surface, graduating
imperceptibly into the agglomerate. One of the most remarkable of
them is to be seen at Glendooey, west of Carrickbroad, where it rises
as an abrupt dark mass on the side of the hill, and, crowned with an
ornamental turret, forms a very pretty and conspicuous object. It
has all the appearance of a volcanic vent, and the tract of dark basic
rock, which spreads to the southward, probably proceeded from it.
This latter has been microscopically examined by Professor Hull,
who finds it to be composed of triclinic felspar and epidote, the
latter, however, occurring as a secondary mineral, and not improbably
having replaced augite. (See Geol. Survey Explanation to accom-
pany Sheet 70, p. 19.)

Although at first it might appear that these basic rocks are newer
than the felstone porphyry, yet there is good reason for believing
that they were formed about the same time, that is, during the con-
tinuance of the same volcanic action. Their graduating into the
agglomerate is a very good reason why we should consider them
coeval with it, and their protrusion through the porphyry is probably
more due to the great differences in the respective fusibilities of
these rocks than to later eruptions. Thus, Prof. Jukes writes :-—
“Granite might become solid at a temperature that would keep
felstone and trachyte still fluid, and these might solidify at tempera-
tures which would keep molten all greenstones, basalts, and dolerites,
so that from the very same stream of igneous matter proceeding |
from the interior to the surface of the earth the more readily fusible
portions might be successively squeezed out, as it were, as the infusible
ones solidified, and contracted in consequence of that solidification.
This action might take place in spite of the greater specific gravity of

Joseph Nolan—Volcanic District of Slieve Gullion, 449

the more fusible minerals, since the difference in the specific gravities
would probably be small compared with the power of the eruptive
force.” And in a note he adds :—* The chemist is reminded of the
fact, that if a mixture of metals, as, for instance, tin, bismuth, and
lead, be melted, they will, as the mixture cools, have a tendency to
solidify and crystallize out separately as the temperature of the mass
reaches their respective melting points. This constitutes a great
difficulty in large bronze castings.” (Student’s Manual of Geology,
p- 92.)

I have now briefly traced the volcanic history of this remarkable
mountain. The first igneous disturbances were apparently those
connected with the formation of granite through metamorphism of
the Lower Silurian sedimentary strata. This action was probably not
unattended with some manifestations of a volcanic nature, all traces
of which, however, were probably removed even before the period of
the Upper Silurian formation ; denudation, assisted by other physical
agencies, having, as we have seen from the example in the West of
Ireland, removed all the superincumbent strata and exposed the
deep-seated metamorphic rocks. At a subsequent period, probably
about the close of the Paleozoic epoch, volcanic disturbances recom-
menced, and the massive dolerites and granitoid rocks were protruded
into, but not through, the granitic area. Simultaneously with this
intrusion, or a little later, a lateral mass of molten rock was projected
sufficiently near the surface to overcome the pressure of the over-
lying rocks, throughout a large area, but, partly on account of the
distance from the volcanic focus, in conjunction with other causes,
the eruption, though violent, was of a very temporary character, and
the great volume of displaced materials falling back into the gulf
still further checked its activity, so that the intumescent mass was
never developed into lava or scoriz.

Perhaps the most instructive feature in the physical history of
this district is the evidence it affords of the intimate connexion
between the granitic and the volcanic rocks. Prof. Jukes writes :—
«Tf we could follow any actual lava-stream to its source in the bowels
of the earth, we should, in all probability, be able to mark in its
course every gradation from cinder or pumice to actual granite.”
(Student’s Manual of Geology, p. 93.) Prof. Judd has recently
demonstrated that in some of the western isles of Scotland this con-
nexion can be traced in all its stages, and the ultimate development
of the granitic rocks into contemporaneous lava flows, with their
accompanying scoriz, ash, and lapilli, is there fully exemplified. In
the district described in this paper, the series, though not so complete,
furnishes another remarkable illustration—showing the passage from
granitoid rocks to others, which, though not actually volcanic, have,
however, approached near enough to that character to give rise to
aériform explosions and the production of a rock analogous to
volcanic agglomerate.

DECADE II.—VOL. V.—NO. X. 29

450 Rev. Maxwell H. Close—Extent of Geological Time.

V.—Tuer Extent or GeorogicaL Time.!}

By the Rev. Maxwett H. Cross, M.A., F.G.S.;
President of the Royal Geological Society of Ireland.

HE question of the geological age of the earth has been of late
very prominently before the minds both of geologists and
physicists. There is no occasion to take up time by giving a sketch
of the late history of the discussion. I beg leave simply to point
out some considerations which seem to lessen considerably the
weight of the physical objections to the great extent of geological
time. Let us observe before proceeding further that we do not wish
to avoid wholesome restriction of geological time. It seems to me
that it adds greatly to the interest of geological investigation to
know that we have not a wilderness of possibility before us as to
the length of time and the consequent deliberateness of geological
operations. If we feel inclined to complain that Sir William
Thomson is rather severe upon us, let us reflect that in this matter
he is generosity itself compared to a certain distinguished collabo-
rateur of his, and moreover that if he lays a burden upon our
shoulders, he supplies us with a good staff to help us in carrying it.
He points out that while the earth was hotter than now, its energy
was greater, and the rate of working of geological agents greater.
This would lessen the need for greatly extended time. We should
admit that there were, probably, two circumstances which would
make that increased energy less readily available, and diminish the
rate of its expenditure. Those are the cloud-covering that must
have enveloped the earth to interfere with radiation, and the greater
extent of sea and smaller extent of land, which is supposed to have
existed in the earlier geological ages, which would lessen the
amount of denudation by diminishing its area. The first physical
objection that we shall now mention is that drawn from the
supposed rate of cooling of our globe, and the time that would be
necessary for it to reach its present thermal condition. Sir William
contemplates granting the geologists 90,000,000 years, though he
may have to allow them only 50,000,000. In making the calcula-
tion it is necessary to make two estimates and two assumptions, on
which to found the calculation. The first estimated quantity is the
increase of temperature per unit of depth in the crust of the earth,
which he takes at 1° Fahr. for 54 feet. The second is the con-
ductivity of the body of the earth, or at least of its less inward part.
Mr. Mellard Reade has shown the great uncertainty there is as to
both of these. The two assumptions are the approximately equable
distribution of the temperature of the globe at its first solidification,
and the constant difference of temperature between the surface and
the interior, of more than 7,000° Fahr.
The next argument for the restriction of geological time which we
shall consider is that the sun cannot be imagined capable of keeping
by its radiation the earth’s surface in a state fit for the support of

1 Being a paper read before the British Association (Section C.), Dublin,
August 21, 1878.

Rev. Maxwell H. Close—Extent of Geological Time. 451

vegetable and animal life for a time as long as the geologist would
require. If I might presume to express an opinion on the subject,
it seems to me that this is the argument which is calculated to cause
the greatest anxiety to geologists. The period of the sun’s radiation
depends upon two principal assumptions, not to mention some others
of much less importance, and these are the amount of heat at the
disposal of the sun, and his power of radiating it. As to the latter,
his radiating power, the physicists have kindly come to our help and
mitigated our difficulty considerably by showing us how to restrain
his otherwise too lavish radiation when he was still young. We
shall content ourselves with thanking them for their help, and pass
to the other point. Now, then, as to the amount of potential heat
that there was in the solar system nebula to be afterwards realized
by the sun. This is calculated on two assumptions, both, it must be
candidly confessed, very reasonable ones, yet both we must at the
same time claim to be not proven. The first is, that the nebula
whence the solar system was to be formed had no energy worth
speaking of proportionately, but the potential energy of gravitation
wherewith to start on its career of evolution ; and the second is that
the unit of gravitation, at least within the range of the original
nebula, and of the resulting solar system, has always been constant.
Dr. Croll’s suggestion in answer to the first of these is well known
—viz. that it may have been the very heat of the nebula which
caused it to exist as such, and that its heat may have been produced
by the collision of two cosmical masses. We shall not go into this
now; we shall merely endeavour to remove the objection that has
been made to it. It is admitted that such collisions occasionally
take place, but it is objected that they are rare, and that the chance
of any particular cosmical body colliding with another within a con-
siderable number of millenniums is indefinitely small. Most true:
but in the first place for how many cosmical «ons were we waiting
for our collision? On foot of this account the geologists have practi-
cally unlimited funds to their credit in the Bank of Time. But
besides this there seems to be some misconception in this objection
of the improbability of this collision. The very same accident or co-
incidence may be to one observer a matter of indifference, and per-
fectly credible on comparatively slender testimony, and it may be to
another so remarkable and striking as to be not easily believed, or
only to be explained as a direct interposition of Providence—accord-
ing to the point of view of the observer, according as he happens to
be concerned with the coincidence. It seems to me that the present
objection has no weight; it has scarcely any meaning except from
the anthropocentric point of view. and that cosmologists ought to
consider cosmological questions from a higher standpoint. But,
besides this, not only does Dr. Croll’s suggestion afford relief to the
geologists, but I respectfully submit that the physicists themselves
might be glad to avail themselves of it.

We are told most truly that the falling together of the materials
of a cold nebula is “a thoroughly intelligible source of heat.” But
what about the source of the cold nebula itself? Is that a thoroughly

452 Rev. Maxwell H. Close—Extent of Geological Time.

intelligible matter? I submit that if we try to trace the line of
causation into a cold nebula, when we have got there we shall find
ourselves in a cul-de-sac, and can go no further. Moreover, we are
not entitled to take it as an ultimate fact without the strongest
reasons. It is not the custom of the physicists to take refuge in
Agnosticism as long as they can possibly avoid it. In other matters
they will trace the steps of causation as far back as they possibly
can. Let us then, instead of going back into a cold nebula which
cannot be accounted for, take the other turn into a heated one, for
which there is “‘a thoroughly intelligible source,” in the relative
motion of cosmical masses which we know to be an actual fact.
We do not know that a cold nebula is a fact in this stage of the
universe. All the nebule of which we know are apparently glowing
with heat, and considering the apparent tenuity of them, and the
enormous dimensions of some, it is highly probable that their heat
is the result of the falling together of their parts. As to the
gravitation attraction being the sole force that was to cause the
molecular falling together of the materials of the nebula, we do not
know that this was so. The shapes of some nebule and the
behaviour of others by no means encourage the belief that the
gravitation attraction is the sole connexion between their parts.

But as to the gravitative attraction itself, granting that it was the
origin of the potential energy of the solar system nebula, do we know
that the unit of gravitation is constant throughout the enormous
interstellar space that has been traversed by our system since it first
began to fall together? Recent physical speculations contemplate
gravitation as being not an inherent essential property of matter
itself. If it were so, we might well suppose it to be unchangeable,
as inertia most probably is. But it is conceived of as depending
upon the action of an external gravific medium, which might or
might not be there. And there seems to be nothing to lead us to
believe that the energy of that medium must be uniform through-
out time and space. Some physicists conceive of that medium as
being itself not amenable to the law of the conservation of energy ;
there is no inconsistency whatever in this. But it is rather a
startling position to take up, and to avoid the necessity of doing
so, Mr. Tolver Preston suggests that the gravific medium may be
comparable in its structure to a gas with an exceedingly great
yet limited mean excursion of its particles. This would limit the
range of gravitation between two material particles, though we have
now nothing to do with that. And he suggests that the light and
heat which is supposed to be entirely dissipated and lost in space
may not be really so—the luminiferous ether may be all the while
paying back to the gravific medium, in some way unknown to us,
the energy which it is expending in producing the heat of the
countless suns. This would certainly be more in analogy with what
we see around us of the transformation of energy. Now, let us join
with this Poisson’s idea that the so-called temperature of space—the
whole radiation of the stars at any place—is not uniform, and it
results from speculations made by physicists themselves, not in the

Rev. Maxwell H. Close—Extent of Geological Time. 458

interests of geology, that the unit of gravitation may not be constant
throughout time, nor through the enormous length of interstellar
space traversed by the solar system mass since it first began to fall
together. We therefore cannot assert that we know what potential
energy was possessed by that mass at that time, and what amount
of heat for the sun to radiate at that time could be produced thereby.
If there is too much boldness in these speculations, it is not the
geologists who are accountable for that. Let us hope that the
physicists may not withdraw them when they find that they may be
turned to the advantage of geology.

We now come to the argument from the figure of the earth,
taken in connexion with the circumstance that her rate of rotation
must be diminishing—diminishing in consequence of the excess of
the retardation caused by the tides over the acceleration caused
by her contraction in cooling. The argument is this—when the
earth consolidated she became as rigid as steel. Then, since the
earth’s figure is now so very nearly that due to her present
rotation rate, she must have consolidated when her rotation was
but little higher than now—that is to say, a comparatively short
while ago. One reply which I have heard made by Professor
Haughton is this—that when the earth had first solidified, her high
temperature would cause rapid cooling; this would produce rapid
contraction ; this would cause acceleration of her rotation, which at
first would overpower the tidal retardation, but after the lapse of
a long time would sink to an equality therewith. Then the tidal
retardation, even though remaining constant, would obtain the pre-
eminence, and after the lapse of another long time bring down the
rotation rate again to what it was at first solidification. So that, for
all that appears to the contrary, the time that has elapsed since first
solidification took place, consists of two long periods, and may be as
great as geologists need wish for. This answer accepts, at least for
the sake of argument, the steel rigidity of the globe, and is, I
conceive, sufficient. But I would beg leave to point out another.

Sir William Thomson has himself very seriously shaken the
foundation of the doctrine of the steel rigidity of our globe. This
doctrine had formerly two grand supports, and, as far as I can find
out, only two. Of these, Sir William has completely shattered one,
that which rested on the amount of precession and nutation; and
he has greatly discredited the other, for the present at least, that
which rested on the magnitude of the ocean tides. He still con-
siders that the evidence of the tides, as far as it goes. points to the
high rigidity of the earth, but he shows that the semi-diurnal and
diurnal tides are to be laid aside for one reason, and the semi-annual
and annual for another. The only tides that he looks to for the
determination of the amount of the earth’s rigidity are the lunar
fortnightly and monthly tides. But now observe, he says, that the
Tide Committee of the Association “have not hitherto succeeded
in obtaining any trustworthy indications of these tides,” but the
indications, such as they are, ‘seem to show possibly no sensible
yielding, or, perhaps, more probably some degree of yielding of the

454 Rev. Maxwell H. Close—Extent of Geological Time.

earth’s figure.” ‘But though the testimony of these two tides is
still so doubtful, let us accept it.” The body of the earth yields
very little to a fortnightly or a monthly change of straining force.
But what about the 18-6 year variation of force connected with the
revolution of the moon’s nodes? Sir William Thomson says, ‘The
absence from all the results of any indication of an 18-6 year tide
is not easily explained without assuming or admitting a considerable
degree of yielding.” Observe how much clearer and stronger his
language is now than before. ‘There being no perceptible 18°6 year
tide in the ocean, we conclude that the body of the earth must yield
nearly as much as water to the variation of tidal force having that
long period, though it will only yield a very little to a fortnightly
or a monthly variation. The meaning of that is, that the rigidity of
the earth, though so high as to amount, is as to quality a viscous
rigidity. The peculiar character of a viscous solid is well known
and illustrated by a stick of sealing wax. The earth, then, may
yield as much as geologists need desire to the continued decrease of
the centrifugal force of rotation. And therefore it may be hundreds
of millions of years since she became solid, although her shape now
so nearly corresponds to her present rate of rotation. There are
quite independent considerations which make it most probable that
the rigidity of substances at a much higher temperature than that of
free fusion, but kept solid by pressure, is generally a viscous rigidity.

I would beg leave to suggest a method by which the yielding of
the earth to the 18-6 year change of tidal force could in all probability
be verified. If there be, as there certainly seems to be, ‘a consider-
able degree of yielding” to this in the body of the earth, it consists
of an alternate rising and sinking of the whole equatorial belt of our
globe together. This must alternately diminish and increase the
rate of the earth’s rotation—diminish it while the moon’s ascending
node is passing (retrogressively) for 8:55 years, from about 15 deg.
W. of the winter to the same distance H. of the summer solstice, and
for 10:05 years v.v. I believe that this change, though very small,
is of an order of magnitude that could be detected by the astronomers
if they would kindly undertake to look for it. They could not use
the moon as their timepiece, her tables not being yet as correct as
would be necessary in this case. But they have promised us revised
tables of the Satellites of Jupiter, and when they shall have fulfilled
their promise the innermost satellite would doubtless make a time-
piece sufficiently accurate for the purpose.

Norr.—The following coincidence seems worth mentioning, though
doubtless only accidental. Professor Newcomb has thrown out the
suggestion that certain unexplained irregularities in the moon’s
motion may be only apparent and caused by inequalities in the
earth’s rate of rotation. He has concluded that, if this be so, the
earth was going slow in her rotation from 1850 to 1862, when she
began to go fast. Now, from the above-mentioned cause the earth
would go slow from November 26, 1852 (or very shortly after), to
March 12, 1862 (or very shortly after), when. she would begin to go
fast again. The near coincidence is curious. But that is all; for,

Notices of Memoirs—George Maw. 455

while the 18°6 year tide in the body of the earth would keep the
earth fast from 1862 only to June 30, 1871, Professor Newcomb’s
observations would show that the earth has been going fast, at least
down to the latter part of last year—1877 ; and besides the changes
caused by the 18-6 year tide could not, I believe, be as large as those
deduced by Professor Newcomb from the apparent variations of the
moon’s motion.

IN OLE ECG Si) O27 ) Mer uNVE@ aaa Se

I.—Groxrocicat History oF THE NortH AMERICAN LAKE Recion.'
By Gzorce Mav, F.L.S., F.G.8.

| Rees Haysville I proceeded to Toronto, thence down Lake

Ontario, with flat shelving shores here and there, with a low
cliff of lake silt, in which, as far as I could observe from the steamer,
glacial boulders were absent, though inland from the lake glacial
drift was everywhere visible. The ‘Thousand Islands,” at the
eastern end of the lake, seemed to consist in part of glacial drift ;
some of the smaller islands of granite or a hard metamorphic rock,
the whole densely covered with low deciduous woods and Hemlock
Spruce. The low rocks were thoroughly rounded by ice action,
possibly by post-glacial floating-ice passing over them, prodigious
quantities of which are annually carried down the river during the
spring thaw. The lake gradually narrows amidst an archipelago of
little islands, and tapers imperceptibly into the great river. One of
the most striking features throughout its length to Montreal is the
absence of that sloping conformation of the land towards the river
channel, the result of graduated subaérial drainage which is character-
istic of most large river valleys, and the St. Lawrence seems placed
inharmoniously in relation to the adjacent land contour. It has its
channel between low banks, and that is all, and the observer fails
to detect that graduated contour which the contributory ramifications
of all ancient rivers have sculptured from their watersheds to their
main channels of drainage; moreover, the St. Lawrence has an
indecisive course, here splitting itself up against trifling obstacles
into numerous channels, again uniting and spreading itself out into
broad shallow lakes over the land, reminding one of the behaviour
of a sudden rush of storm-water over a course unprepared for it.
The St. Lawrence is obviously a new river and supplies a fresh
line of drainage compared with the ages of many other rivers, and
its history must be viewed in relation to the origin of the great
chain of lakes of which it is the outlet.

The surface levels of the lakes step gradually upwards. Ontario
is 235 feet above thesea; Hrie, 564 feet; Huron, 595 feet; Superior,
627 feet above the sea. But their depths have no relation to the
order in which they occur from the watershed to the sea, for the
bottom of Ontario nearest the sea is 365 feet below the sea-level.
The bottom of Erie is 462 feet above the sea-level of Huron, 145
feet above the sea; and of Superior, at the inland end of the chain
- 1 Extracted from “ American Notes,’ Gardeners’ Chronicle, 1878, pp. 169, 170.

456 Geological History of the Lake Region.

of lakes, 65 feet below the sea. Michigan is merely a great bay
lying off from the main line of drainage. It is obvious that the
present relative depths of the connected chain of lakes are incon-
sistent with their being merely the flooded sections of an old river
valley, for the bottom of Ontario, the lake nearest the sea outflow,
is 365 feet below the sea, and 600 feet below its own outflow into
the St. Lawrence; the bottom of Superior, the lake furthest inland,
is 65 feet below the sea, and 527 feet below the bottom of Erie,
which intervenes, and no less than about 570 feet below the river-
bed outlet of Erie.

A glance at the map will show how closely the watershed line
environs the great lake district. The lakes receive no long rivers,
and it is a mere narrow belt of land that drains into them, beyond
which the drainage goes north towards Hudson’s Bay, south towards
the Mississippi, and east by the Ottawa. Several of the rivers
running into the great lakes have on the map a curious aspect of
continuity with the tributaries of the Mississippi system; this is
especially noticeable in the case of the Wisconsin flowing into the
Mississippi, and Fox River flowing north-east into Green Bay of
Lake Michigan. The same relation is observable between the
Wabash flowing into the Ohio, and the Maumee running into Lake
Hrie; and it is worthy of observation that the tributaries of the
Maumee are bent back in a direction rather ranging with the
direction of the confluents of the Wabash than with that of the
Maumee, with which their main course forms an acute angle against
the stream. If the lake area is a region of depression, it seems
possible that the extremities of the confluents of the Mississippi
may have been depressed towards the lakes, and the waterflow
diverted northwards without the old valleys being obliterated.

We must set aside the view that the chain of large lakes is due
to glacial excavation; for Ontario, the deepest of the lakes running
east and west, is in lower latitude than Huron, the bottom of which
is 510 feet above that of Ontario, and there is no high ground about
Ontario from which ice could have originated as a preponderating
mass, capable of excavating Ontario 600 feet deep ; nor is there any
such mass of débris anywhere to be seen about the lake as would
represent such an excavation.

New York State, bordering on Ontario, abounds with small lakes,
running north and south, between escars and drift ridges, evidently
of glacial origin, and which have nothing in common with the
direction or character of the larger lakes, which must be the result
of the subsidence of the area, bounded by their environing water-
shed, resulting in a fresh basin of drainage towards the Atlantic,
the former drainage of which was divided between the Mississippi
basin, Hudson’s Bay, and the Ottawa. The contour of the land
surface north and south of the great lakes seems to indicate that the
subsidence of the containing area was subsequent to the glacial ex-
cavation of the numerous small lakes running north and south, and
it seems probable that the Niagara gorge, as well as the St. Lawrence,
down to its junction with the Gttawa River, are of post-glacial origin.

Notices of Memoirs—Prof. E. Hull. 457

II.—On tHe Gronogy or tHe Environs oF Dusiin.' By Prof.
HK. Hut, M.A., F.B.S.

YJVHE author remarked that the subject had been ably treated by

the Rev. Maxwell Close, President of the Royal Geological Society
of Ireland, in the hand-book issued by the Local Committee of the
British Association. An excellent account of the same subject had
been given by Mr. Baily, and also in the very interesting publica-
tion called ‘“‘Science Gossip.” It had been the habit to begin the
meetings of the Section by giving a short description of the locality
in which the Section met, and in conformity with that custom he
would give a brief account of the geological structure of the
environs of Dublin. Before doing so, he might refer to the physical
features for the benefit of the strangers, who had honoured them
with their presence. The first feature that strikes the stranger
upon entering Dublin Bay is the beautiful range of hills, with their
several sharp or prominent peaks, lying to the southward. These
are the extremely northern points of the Dublin and Wicklow
mountains, which might be called the south-eastern highlands of
Ireland. They commence in the neighbourhood of Kingstown and
Killiney, and extend in nearly a southerly direction to Waterford,
a distance of about 40 miles, with an elevation at Lugnaquilla of
3089 feet. To the north and west of this range extends the great
central plain of Ireland, which stretches from the shores of the
Trish Sea, between Dublin and Dundalk, across the country towards
Galway Bay. It is bounded on the south of this range of hills,
which commences at the Devil’s Bit, extending southwards towards
the county Limerick, crossing the Shannon above Limerick, and
going towards Clare and Galway; thus forming the outworks of
the great south-western highlands, which includes the mountains
of Kerry, Cork, and Waterford. To the north there is another
range of hills of not so great an elevation, and then to the west are
the western highlands of Galway, Mayo, and Sligo, including the
beautifully picturesque tract of Connemara. All these hills are of
older formations than the central plain. They rise from beneath
that plain, throwing off the newer formations in every direction.
It is a curious geological paradox that the oldest formations
generally occupy the highest ground. As to the geological
structure, it might be better to take the order of deposition or
natural order of birth. The oldest formations in Ireland are repre-
sented in the neighbourhood of Dublin to the north and south of
the bay. This formation is called the Cambrian, similar to the
Lower Cambrian in North Wales. They consist of enormous thick-
nesses of reddish and green slates, grits, and quartzites traversed
by great fissures. These beds are very well laid open along the
railway cuttings at Bray Head, where some would have an oppor-
tunity of inspecting them on Saturday; also at the Hill of Howth,
where the strata was of a precisely similar character. They were
characterized by very simple forms of animal life—Oldhamia of two

- lRead before the British Association for the Advancement of Science, Dublin,
(Section C.), August 15, 1878.

458 Notices of Memoirs—Prof. BE. Hull—

species, and also by tracks and borings of marine worms. This
formation was immediately succeeded by what was called the
Lower Silurian, which formed the main tract of the country, ascend-
ing the mountains in some instances even to the summit of Lugna-
quilla, the core of the range being granite. This granite had been
intruded through the Silurian rocks, and, curiously enough, not
through the Cambrian rocks, but had affected the Lower Silurian
rocks to such a degree that, from being formed of fossiliferous slates
and grits of a darkish grey and brown colour, they had been con-
verted into what was called “metamorphic strata,” accompanied by
the development of certain minerals. Mica had been developed
where these rocks came into close proximity with granite. Granite
was, therefore, of a newer date than these Lower Silurian rocks, for
otherwise the Lower Silurian would not have been metamorphosed
by contact with the granite. The junction was very well seen in
numerous places, especially at the foot of Killiney Hill, where the
dykes of granite could be seen penetrating the slaty and micaceous
schists, also at the remarkable gap, the Scalp, and on ascending
Glendalough Valley. The chief limestones were to be found at
the chair of Kildare, and on the east coast opposite Lambay Island.
These were representatives undoubtedly of the Bala limestone of
North Wales, and had yielded a magnificent series of fossils
representing the Lower Silurian period. This brought them to
the subject of the age of the Dublin and Wicklow mountains ;
when they were first elevated; when they first received their
great foldings and contortions, and when the enormous mass of
molten matter now constituting granite was first intruded amongst
these bodies. 'To determine this question they had of course to refer
to formations newer than the Lower Silurian. At the extremity of
the Wicklow and Wexford range they found Old Red Sandstone
resting discordantly on the upper edges of the Silurian rocks. There-
fore, the Old Red Sandstone was newer than the period of metamor-
phosis, which was the period of the first birth of these mountains.
Just as in Scotland, along the flanks of the Grampian Hills, they
found the Old Red Sandstone resting upon the crystalline rocks,
which were of the same age as those of the Dublin mountains. Thus
they had in both countries similar phenomena. The Silurian rocks
were upheaved and converted into land before the Old Red Sandstone
period. He believed the age of the Dublin and Wicklow mountains
might be placed at that interval of time which elapsed between the
close of the Lower Silurian period and the commencement of the
Upper Silurian period. The Old Red Sandstone was scarcely repre-
sented within the area described, except in the neighbourhood at
Kiltorcan, on the borders of the counties Wicklow, Wexford, and
Carlow. It had, however, yielded some magnificent ferns and other
fossil plants which could be seen in the Museum of the College of
Science. The next formation was the Carboniferous, which was,
perhaps, the most important, extending over the plain north and
south, and principally represented in the neighbourhood of Dublin.
It consisted of three divisions—lower, middle, and upper. The

On the Geology of the Environs of Dublin. 459

middle was of an earthy character, darkened by carbonaceous mate-
rial, probably that of marine alge. The whole formation was
undoubtedly a great marine or oceanic deposit. It was in the first
place full of marine shells, the same as those existing in the sea at the
present day. Taking a thin section of any specimen of Carboniferous
Limestone, however dense and apparently unfossiliferous, let the slice
be so thin as to be transparent under a microscope, and they would find
it consisted of a mass of shells resembling those of the little animals of
the simple forms of life which exist in such vast numbers over the floor
of the ocean at the present day, namely, Foraminifera. The Carboni-
ferous Limestone was in all about 38000 feet thick, so that the
building up of the great organic formation over the floor of the ocean
must have taken a period of indefinite duration. When they went
to Kilkenny and Carlow, they found the representatives of the Middle
and Upper Carboniferous series analogous to that of the British and
Welsh Coal-fields. Professor Hull then proceeded to refer to glacial
deposits. No one had contributed more to the elucidation of this
subject than the Rev. Maxwell Close. He had shown that the whole
of this part of Ireland was at one time covered by a thick sheet of
ice, which has left its marks upon the solid rock wherever that rock
has been sufficiently protected to prevent the marks being obliterated
by time. Those who would be able to be present at the examination
of Bray Head on Saturday would have an opportunity of seeing the
glacial scorings and groovings upon the surface of the quartzite near
Killiney Hill. Drift formations were well represented in the neigh-
bourhood of Dublin. They consisted of three divisions. The oldest
was Boulder-clay—a formation which disgusted and dismayed engi-
neers and contractors, but had furnished a good deal of interesting
speculation to geologists. It contained blocks of rock generally
glaciated or worn by ice, grooved, and scored. Some of these glacial
stones were to be found in the present excavations at Stephen’s
Green. The stones were not only grooved and scored, but had a
polished surface, showing that they had been ground and rubbed
over solid rock as the ice was moving along. Undoubtedly the
Lower Boulder-clay was the result of the original ice-sheet which
covered the whole country, moving in the neighbourhood of Dublin
from the north-west towards the east and south-east, and, what was
very remarkable, moving through the central plains over the hills
which rise between it and the sea, by a force he was not going to
speak further of. Let them just fancy that sheet of ice being obliged
to pass from the lower ground over such hills as Killiney and Bray
Head out towards the sea. The Lower Boulder-clay was succeeded
by another series of drift strata, entirely different, consisting of
stratified sands, gravels, and marine shells. A beautiful selection
of these shells was open for examination at Howth, close to the
telegraph-station at the beach, and in half an hour an excellent col-
lection of glacial shells of the period might be obtained. These
shelly gravels were, of course, deposited under totally different con-
ditions from Boulder-clay, which underlay them, because they were
evidently deposits which had been formed in the sea of the period.

460 Notices of Memoirs—Dr. Henry Hicks.

These shelly gravels only covered portions of a lower tract of
country in the neighbourhood of Dublin, and they ascend the flanks
of mountains to the height of 1100 or 1200 feet above the sea,
showing, he thought, that the land had subsided to that extent
beneath the sea, so that only the mountains of higher elevations
would rise above the level of the water and appear as islands.
There was another very remarkable formation, that of the Upper
Boulder-clay, which could be seen at Howth, and which succeeded
that to which he had alluded. There was only one other formation
to which he would refer, and that was the remarkable raised
beach which extended along the eastern coast from Wicklow to
the Giant’s Causeway, round to Donegal. This raised beach was
represented by a terrace of shelly gravel belonging to the neigh-
bouring seas, and showed that the shore had been within a very
recent period elevated from 3 to 4 or 10 feet in the neighbourhood
of Dublin, and to a greater degree in the North. This beach was
shown by the Esplanade at Bray, which was really an old sea-
bottom raised five or ten feet above the original position. In the
North of Ireland the shelly beach was found to contain some of
those arrow-heads and flint instruments to which the President had
alluded. They would see from what he had said that they had
within a short compass a very considerable series of formations, and
he hoped the sketch he had given would enable geologists, and
those who took an interest in the subject, to better understand than
they otherwise would some points of interest in the geological
structure of the neighbourhood of Dublin.

I1I.—Ow some New Pre-Camprian Arzas in Watss.! By Henry
Hicxs, M.D., F.G.S.

URING some recent researches in Wales the author has been able to

add many new areas to the pre-Cambrian rocks already described.

In these examinations he has been assisted at different times by Prof.

Torrel, of Stockholm, Prof. McKenny Hughes, Mr. Tawney, F.G.S.,

and Dr. Sterry Hunt, of Montreal. The additional areas to be now
added to those previously known are :—

1. Some cupriferous schists with their associated greenstone bands
(the so-called intrusive greenstone of the Geological Survey) to the
north of Dolgelly, and including a great portion of Robel Tawr.

2. Masses of granitoid rocks, porphyries, and greenstone breccias,
in the neighbourhood of Pwllheli.

0. The porphyries and granitoid rocks forming Mynydd Mynytho,
and extending in a northerly direction towards Nevin, including
also Nevin mountain and the porphyries and greenstone breccias to
the north-east of Boduan.

4, The Rhos Hirwain syenite and the so-called altered Cambrian
beds to the west of that mass in Caernarvonshire, and also Bardsey
Island.

1 Abstract of paper read before the British Association for the Advancement of
Science, Dublin (Section C.), August 19, 1878.

Notices of Memoirs—Prof. W. C. Williamson. 461

5. The granitoid rocks, felstones, and porphyries, forming the
Rivals (yr Eifl) range of mountains.

6. The so-called altered Cambrian rocks to the west of the Peny-
groes porphyry.

7. The so-called intrusive granite in Anglesea, and the whole of
the area marked as altered Cambrian in that island. In addition to
these he has also extended some of the areas and defined more
clearly the order of superposition of these rocks in Pembrokeshire.
In North Wales, as in South Wales, he found that the pre-Cambrian
rocks resolved themselves into three well-marked and very distinct
types, and that these indicated separate formations, each of which,
on careful examination, and when found in juxtaposition, proved to
be unconformable to the other. At St. David’s the granitoid rocks
occur at the base, and, resting unconformably upon these, are found
the quartz-felsites. These are again succeeded unconformably by
the agglomerates, breccias, greenstone bands, and schists of the
Pebidian group.

In North Wales this was also exactly the order in which the
various rocks were found to succeed each other, but the middle or
quartz-felsite group was found more largely developed in Caernar-
vonshire.

As this middle group had not previously been separated under a
distinguishing name, the author now proposed to adopt for it the
name Arvonian, from the Roman name Arvonia, and from which the
present name of Caernarvon is derived. So many of the large ridges
and lofty mountains of Caernarvonshire are composed of these felsitic
rocks, that it appeared to the author and his friends that this name
would be very appropriate for the formation. The distinguishing
characters most marked in these three pre-Cambrian formations may
be briefly summed up as follows :—

1. Dimetian: Granitoid gneiss and quartzose rocks.

2. Arvonian: (Quartz, felsites, and porphyries (Helleflinta of
Torrel ; petro-silex rocks, Hunt).

3. Pebidian : Green and purple agglomerates and breccias, green
chloritic schists, with massive greenstone bands, talcose schists, ete.

In these formations the bedding is usually easily recognized, but
at present the actual stratigraphical thickness cannot be correctly
estimated. It is perfectly clear, however, from the sections ex-
posed, that each must have a vertical thickness of many thousand
feet. That they have a very extended geological distribution over
the British Islands is also daily becoming more and more evident.

IV.—On tHE Suprosep RapIoLARIANS AND DIATOMACE® OF THE
Coat-Mrasurgs.’ By Professor W. C. Witu1amson, F.R.S.

HE author called attention to the Traquarig of Mr. Carruthers,
found in the Lower Coal-measures of Lancashire and Yorkshire,
which small spherical objects that observer believed to be Radio-
larians like those still living in existing seas. The author showed

' Read at a Meeting of the British Association, Dublin (before Section D,
Biotocy), August 19, 1878.

462 Notices of Memoirs—C, E. De Rance.

that the radiating projections with which these spheres are sur-
rounded were not siliceous spines like those of the Radiolaria, but
extensions of a continuous membrane which inclosed the entire
organism, and which, therefore, could not have the spicular nature
attributed to them. He then demonstrated that within this external
membrane is a second inner one, which latter is fitted with
numerous small vegetable cells like those shown to exist in the
interior of fossil spores and reproductive cryptogamous capsules,
found in the same beds as those which furnish the Traquarie.
These conditions are so different from those existing in any known
recent species of Radiolarian as to lead Professor Williamson to
reject the idea of their Radiolarian character. Their close organic
resemblance to some obviously vegetable conceptacles found in the
same Coal-measures suggest that the Traquarie are also vegetable
structures. The Mountain Limestone deposits of some British
localities contain a vast multitude of minute calcareous organisms,
which Mr. J. W. Sollas and other observers regarded as Radiolarians.
These. structures, however, seem to exhibit no satisfactory evidence
of being so. In the first place, these organisms are calcareous
instead of siliceous. It has been suggested that their siliceous
elements were removed and replaced by carbonate of lime, but this
appears to be most improbable. Professor Roscoe and Professor
Schorlemmer agree in stating that they would require overwhelming
evidence before they would be prepared to accept such an explana-
tion of the present condition of these objects, or of the fact of the
substitution of carbonate of lime for silica, which such an explanation
renders necessary. Count Castracane has published! an account of
a process by which he reduced numerous specimens of Coals to very
minute quantities of Coal-ash, and has stated that he found in these
ashes numerous marine and freshwater Diatomacesze. Professor
Roscoe kindly allowed one of his ablest assistants in his laboratory
at Owens’ College to prepare analyses of a number of Coals ac-
cording to Count Castracane’s method. The residual ashes of these
preparations have been tested microscopically by Professor William-
son, and in no one of them can a trace of a Diatom be found.
Beyond stating the fact, he is wholly unable to account for the
discrepancy between his results and those of the Italian observer.
So far as his present observations go, he finds himself compelled to
conclude that we have no proof of the existence of Radiolarians or
of Diatomacez in the British Carboniferous rocks.

V.—Unvbererounp Waters.2 Fourta Report or tar ComMITTEE
on UnprrcrounpD WaTERS IN THOSE Districts IN ENGLAND
WHERE THEY ARE NOT AT PRESENT USED. By C. H. Dr Rancz,
F.G.S8., Assoc. Inst. C.E.

HE author referred to the great value of the maps of the
Government Geological Survey as a basis for the investigation
1 See Grou. Mac. 1875, Decade II. Vol. II. p. 414.

2 Read before the British Association for the Advancement of Science, Dublin,
16th August, 1878 (Section C).

Notices of Memoirs—W. Traill. 463

in question of the water supply. He stated that the area occupied
by permeable formations capable of yielding water in wells sunk in
suitable situations was no less than 26,687 square miles, which,
receiving a rainfall averaging 30 inches a year, would yield up to
wells not less than 6 to 15 inches, or a daily quantity of not less
than 200,000 gallons for each square mile of surface, or a total
quantity far in excess of that required by the population of England
and Wales. The great value of these supplies for the towns and
districts of the Midland districts was insisted on by reason of their
purity, and from the absence of strong Parliamentary opposition,
which is encountered in all large gravitation schemes, whether the
water be proposed to be taken from natural lakes, as in the scheme
for Manchester, or from artificial reservoirs, as in the proposal for
Liverpool. The well-boring at Bootle, near Liverpool, completed
for the Liverpool Corporation by Messrs. Mather and Platt, was
described as of great interest, the boring having reached a depth of
1,000 feet without reaching the base of the New Red Sandstone. The
Committee expressed a hope that this boring may be continued, as it
will settle several questions, not merely of local interest, but of
national importance.

VI.—On toe Rocks or Utsrer as A Source or Water Suppty.!
By W. Tratut, M.A.I., F.R.G.S.L, of the Geological Survey of
Ireland.

HE author first contrasted the backward state of the study of
hydro-geology in Ireland with its advanced progress in England.

The necessity for better water supplies had been recognized by the

larger towns, which had accordingly been supplied, but too many of

those, with populations of 5,000 to 1,500 inhabitants, were still
supplied only by shallow surface wells, a source universally con-
demned as scarcely possible to be free from sewerage pollution, the
fruitful parent of disease. The two great systems of water supply
were contrasted, that by catchment basins with large reservoirs,
and that by deep wells or borings, the latter where practicable being
undoubtedly considered the best. The rocks of Ulster were then
reviewed with regard to their suitability as sources of water supply.

The Lower Silurian rocks of Down, Louth, Armagh, and Monaghan

did not possess the essential qualities necessary for success; neither

did the granitic tracts of Mourne, Newry, or Rathfriland, nor the

metamorphic rocks of Donegal and part of Londonderry, nor the

districts of the Carboniferous Limestone. The New Red Sandstone
formation, one of the great sources of water supply in England, was
shown to occupy in Ulster a very limited surface area, in some
districts yielding water by boring, and likely to prove productive
in other places also, but requiring special selection of sites for
operations. The Chalk and Hibernian Greensand formations were
shown to be the great water-bearing rocks of Ulster, as evidenced
by the large number of perennial springs along their outcrop. The
geological basin of the Cainozoic in the counties of Antrim and

Read before the British Association, Dublin, in Section C, August 19, 1878.

464 Notices of Memoirs—Prof. E. Huil.

Londonderry was clearly demonstrative from the heights of the
outcrop of the Chalk, up to elevations of a thousand feet; and its
occurrence inside the basin, at Templepatrick and other places,
was proof of its continuity below the basaltic plateau at a low
level. The water, being held under hydrostatic pressure in the
Cretaceous beds underlying impervious clays of the Lias or Keuper
marls, required only to be tapped by boring through the overlying
sheet of basalt to yield a practically inexhaustible supply of pure
and wholesome water. The districts most favourably situated for
thus yielding water supplies by boring were near Ballymena, Bally-
money, Coleraine, Antrim, etc. The author stated that for most
localities the requisite depth to meet the Chalk could be readily
calculated. He also enumerated the other water-bearing strata
existing in the same sections, as at the lithomarge bed of the Iron-
ore measures, and at the lower lithomarge bed, and also at the
surface of the basalt if under a considerable head of drift. The
author strongly advocated the adoption of boring for water supplies
for certain districts in Ulster, as that system had been so advanta-
geously adopted in England.

VII.—Tur Progress or THE GxronocicaL Survey oF IRELanp.!
By Professor E. Hunn, M.A., F.R.S., Director of the Geological
Survey.

| ecareoenene HULL gave a short account of the progress of the

Geological Survey of Ireland from its commencement in 1882,
under the late General Portlock, R.E., down to the present day,
stating that the whole country south of a line drawn roughly from

Larne on the coast of Antrim to Sligo had been surveyed, while 160

Sheets of the Geological Map, on a scale of one inch to the statute

mile, had been published. Along with these had also been issued

78 separate Explanatory Memoirs describing the structure and

paleontology of 126 Sheets. It had been found necessary to revise

the geology of the Leinster and Tipperary Coal-fields, the Carboni-
ferous trap rock of the County Limerick, and the South-East portion
of the country, including parts of Wicklow and Wexford. The Coal-
fields of the North of Ireland had also been surveyed and published
in maps both on the 6-inch and 1-inch scales; and it was also
intended that the districts of the County Antrim containing pyrolitic
iron-ores should be illustrated by maps on both scales. The district
still remaining to be examined included the greater portions of

Donegal, Tyrone, Fermanagh, Sligo, and Antrim. Professor Hull

entered into a brief description of the geology of the various parts of

Treland.

VITI.—On ‘Hourirz,’ a HITHERTO UNDESCRIBED Mrnerau.! By
E. T. Harpman, F.C.S.
HE author stated that this mineral occurs in abundance at Carn-
money Hill, near Belfast, in the basalt forming the neck of a
Miocene volcano. It has never been described before or analyzed,

1 Read before Section C, Dublin, 20th August, 1878,

Notices of Memoirs—Prof. W. King. 465

and has been referred to in the Survey maps and labelled in the
Survey collections as obsidian, doubtless from its black colour and
waxy lustre. In physical character it somewhat agrees with the
Chlorophzite of Maculloch, but is entirely different in composition,
which more resembles that of Delessite. From this, however, it
differs essentially in colour, hardness, streak, and specific gravity,
but it appears on the whole to belong to the ferruginous chlorite
group. Physical characters—Colour, velvet black; hardness, 2 ;
brittle ; lustre, waxy to dull; very slightly affected by acids; occurs
at Carnmoney and Shane’s Castle, near Lough Neagh. The chemical
composition of the mineral was given, and compared with those of
Delessite and Chloropheite. Its most remarkable characteristics are
its low specific gravity and its resistance to the blow-pipe—both
curious points, considering the large quantity of iron it contains.
The author proposed to call the mineral Hullite, after Professor
Hull, in commemoration of the valuable work he has done in eluci-
dating the microscopic mineralogy of the basalts of Ireland. Pro-
fessor Hull has examined the microscopic structure of the mineral,
and of the rock in which it occurs,.and has described the appearance
presented by the mineral. Under the microscope it is of an amber
brown colour, nearly opaque. It permeates the whole rock, filling
the interstices, and inclosing the other minerals. It appears very
much to assume the character of chlorite, and is undoubtedly a distinct
mineral, and not a product of alteration.

TX.—Ow tue Ace or tHe Crystauiinge Rocks or Donzaau.! By
Professor W. King, D. Sc.

HE author said that the Crystalline Rocks of Donegal had been
carefully studied, both in their petrological and geographical
features, by Hampton, Scott, Harte, Griffith, Jukes, Blake, Harkness,
and others; but among them some authors had succeeded in de-
termining their geological age by means of fossils. It was true that
the limestones in the Innis lower barony, in the northern part of
the county, contained bodies which had been suspected to be the
remains of corals, but it was to be regretted that none of these
bodies, so far as is known, possessed sufficient evidence to enable
paleeontologists to offer a decided opinion as to their nature. Having
been lately in Donegal, besides examining their mineral and
structural character, he embraced the opportunity of endeavouring
to find if any of the rocks occurring in this county, especially the
Innis Lower Limestones, contained fossils. In the south coast
division of Donegal, between Lough Foyle and Lough Swilly, where
the least altered rocks prevailed, some of the limestones had ap-
parently undergone so little alteration that it might be expected
that they would retain the remains of any organisms originally
inclosed in them. The bodies taken for fossils and corals consisted
generally of white calcite, and they were occasionally found of a
cylindrical shape, with what appeared to be internal radiating plates
1 Read before Section C, Dublin, August 21, 1878.
DECADE II.—yVOL. V,—NO. X. 30

466 Notices of Memoirs—Dr. T. Sterry Hunt—

Notwithstanding that the contrary had been expressed, he could not
but strongly suspect that they were actually the remains of large
corals. He had, however, succeeded in obtaining some true fossils
from portions of the Innis Lower Limestone, that had scarcely
undergone any change. He had not had time to examine them as
closely as he would have wished, but they appeared to be Caradoc
Bryozoa from the schists of Donegal. ‘This was the first example,
as far as he could ascertain, of an undoubted fossil having been
detected in these limestones. ‘The fact may be taken as evidence
that these deposits and their argillaceous and siliceous masses are
of Lower Silurian age, and it seems highly probable that the more
intensely metamorphosed rocks in the north-west division of
Donegal belong to the same geological period.

X.—TuHeE ORIGIN AND SUCCESSION OF THE CRYSTALLINE Rocks.! By
Prof. T. Sterry Hunt, LL.D., F.R.S.

he a preliminary to a statement of the results of many years of
study of the crystalline rocks in North America, the author
proceeded to consider the question of their origin, which is still a
subject of debate between Plutonists and Neptunists. The crys-
talline silicate rocks naturally divide themselves into three groups—
namely, those indigenous stratified formations which have been
called primitive, or primary; those masses to which, from their
relations to contiguous rocks, geologists assign an exotic origin, and,
in accordance with a generally accepted theory, have agreed to call
igneous or plutonic; and a third and distinct group of rock-masses
which, though like the last, clearly posterior to those encasing them,
are now, by most geologists, admitted to be of aqueous origin. This
third group includes metalliferous lodes, and various other crystalline
veinstones, and is conveniently designated endogenous. It is not
always easy to distinguish between the rocks of these three groups ;
there are not wanting those who have assigned an igneous origin to
metalliferous lodes, and many still confound endogenous granitic
veins with the mineralogically similar plutonic granites. In like
manner, the distinction between the latter and the stratified granitoid
gneisses is frequently not very apparent. That the movement of
flow in extravasated plutonic rocks may give to the constituent
minerals a stratiform arrangement, is a fact of which both exotic
granites and doleritic dykes and masses afford illustrations. More-
over, the arrangement due to successive depositions upon the walls
of a fissure may give to an endogenous mass a structure which
simulates that of a sedimentary rock, and imparting to granitic
veinstones a resemblance to gneiss; while a laminated structure
sometimes results from the arrangement of the crystals developed in
a cooling mass. Hence there are not wanting those who include
under the head of plutonic rocks not only the clearly marked exotic
granites, dolerites and diorites, but the granitoid gneisses, the massive
bedded greenstones, and likewise the more schistose rocks with which
these gneisses and greenstones are often so intimately associated that
1 Read before the British Association, Section C, Dublin, August 19, 1878.

Origin of the Crystalline Rocks. 467

it is difficult to separate them. According to those who hold this
plutonic view the crystalline rocks represent the igneous crust of
the globe, and their frequent stratiform structure is due to agencies
in great part anterior to the production of sedimentary rocks. In
opposition to this view is that of the Neptunist, who, starting from
the fact that the elements of an aqueous sediment may through the
action of chemical and crystallogenic forces, pass into new combina-
tions and acquire a new structure, argues not only that all indigenous
crystalline rocks have had an aqueous origin, but that the exotic
masses themselves represent the last stages in this process of altera-
tion or metamorphosis of sedimentary beds.

Further inquiry into the chemical and lithological composition of
the crystalline rocks, however, brings to light difficulties in the way
of both of these hypotheses. To begin with the Plutonist view,
volcanic rocks, both ancient and modern, are more or less nearly
related in composition to the gneisses and the stratified greenstones,
but we seek in vain among undoubted volcanic or igneous rocks for
the chemical representatives of the masses of serpentine, olivine,
steatite, chlorite, quartzite, magnetite, oligist, and limestone, which
appear in the primary formations, and have, all of them, by geologists
of the school in question, been regarded as of igneous or plutonic
origin. ‘To account for the presence of such rocks among the more
or less felspathic aggregates—chiefly gneisses and greenstones,
which make up the greater portion of the crystalline formations—
three hypotheses have been imagined by Plutonists. According to
the first of these, the earth’s imterior is a reservoir, from which at
times have been ejected not only basic and acidic felspathic rocks,
but molten masses of olivine, iron-oxide, quartz, and limestone.
Other geologists of this school have sought to account for the presence
of some of these exceptional rocks by a process of so-called segrega-
tion, which would assimilate them to endogenous masses. The
chemical and geognostical difficulties in the way of both of these
hypotheses have, however, led to their general rejection for the
third, which supposes these rocks to have been formed by a subse-
quent local alteration of portions of the ordinary plutonic rocks.
From acknowledged cases of alteration or replacement in mineral
species, which result in pseudomorphs, and from the more frequent
cases of envelopment and isomorphism which have been taken for
examples of pseudomorphism, it was argued that many species are
capable of being changed into others by the loss or addition of certain
elements, so that the resulting body often contains no portion of its
original constituents. LHxtending this view from single crystals to
rock masses, it was maintained that different portions of an igneous
or plutonic formation, whether basic or acidic, might be transformed
into serpentine, chlorite, or limestone. Those changes were supposed
to depend on the action of water, which, aided by heat, was regarded
as the efficient agent in the local alterations of plutonic rocks. At the
same time, the adjacent sedimentary strata were supposed to share
in these changes, thus giving rise to what have been called contact
formations. In their latest form these doctrines have been well set

468 Notices of Memoirs—Dr. T. Sterry Hunt—

forth by Von Lasaulx and by Knop. This third hypothesis then
proposes to account for the presence of various exceptional varieties
of rock among ordinary plutonic formations, by supposing that
limited portions of these have at different times been the subject of
very unlike chemical processes, resulting in their complete change
into new forms of rock by what has been called pseudomorphic alter-
ation, or metamorphosis. As, however, such a conversion involves
a change not only of form, but of substance, it has been more pro-
perly designated a metasomatosis.

We have next to consider the Neptunean views as ordinarily ex-
pounded. This, while it accounts by sedimentation for the stratiform
arrangement of the crystalline rocks, and explains the existence
therein of beds of iron ores and limestones, still presents many of
the difficulties which are encountered in the Plutonist view. If, as
most Neptunists maintain, the great crystalline series have been
derived from the alteration of uncrystalline ones, which were not
only similar to those of Palaeozoic and more recent times, but are, in
fact, portions of those which in adjacent regions are still known to
us in their original unchanged condition, how are we to explain the
genesis of the felspathic and hornblendic rocks which predominate in
these crystalline formations? The sandstones and shales from which
in this view they are supposed to be formed could never by them-
selves give rise to the rocks in question, since they are deficient in
the alkalies, and to a greater or less extent in the other bases
required for the production of the constituent silicates. To explain
their origin, therefore, it becomes necessary to admit the intro-
duction of these various bases from without, and to suppose a series
of metasomatic processes more wonderful than those imagined by
the Plutonist. The latter, by his hypothesis, has already at hand
felspathic and hornblendic rocks, which are to be the subject of
metasomatosis, while the Neptunist has only the products of their
decay. In either hypothesis, we have to account for the presence in
the primary formations of beds and interstratified masses of a great
number of exceptional silicated rocks, very distinct in composition
from any mechanically-formed sediments, including not only silicates
like serpentine, olivine, steatite, chlorite, pinite, garnet, epidote,
and hornblende, but of pure orthoclase, as well as of triclinic
felspar. Hach of these species would require for its production
from any ordinary igneous or aqueous rock a separate and inde-
pendent metasomatic process, involving the addition of certain
elements, and the abstraction of others, until the whole hetero-
geneous crystalline series was complete. The author illustrated
these views by examples from recent writers, and concluded that
the hypothesis of metasomatosis, as maintained both by Plutonists
and Neptunists, supposes the operation in solid rocks of processes
of circulation, absorption, elimination, selection, and aggregation
scarcely to be equalled in the economy of bighly-organized beings,
and not easily imagined in the masses of the mineral kingdom.
Certain geologists suppose the existence of two classes of crystalline
stratified rocks, the one Neptunean, and consisting of altered portions

Origin of the Crystalline Rocks. 469

of Paleozoic or more recent sediments ; and the other—more ancient
—which may be either Neptunean or Plutonic in origin. The history
of geology gives many examples of crystalline formations which
have been in turn assigned to various geological horizons, from the
Cainozoic to the base of the Paleozoic, but have since been found to
belong to a pre-Paleeozoic period. In the opinion of the author, we
have no good and sufficient reason for believing in the present
existence of any uncrystalline representative of these crystalline
formations, or of any such formation which is not pre-Silurian, if
not pre-Cambrian, in age. There are, however, many examples of
local alterations of later sediments by hydro-thermal action, which
has developed in these many crystalline minerals identical with
those found in the more ancient rocks.

The advocates of the Neptunean hypothesis have, for the most part,
sought for the origin of the crystalline rocks in sediments of a later
date, of which the uncrystalline representatives are still to be found.
There are, however, reasons for believing that in Hozoic, or pre-
Cambrian times, there prevailed chemical activities dependent upon
greater subterranean temperature, different atmospheric conditions,
and abundance of thermal waters, and that under these circumstances
were deposited the materials for the crystalline rocks. There have
not been wanting those who have sought in similar hypothetical
conditions for the origin of these rocks. De la Beche, in 1884,
imagined them to be chemical deposits due to the action of the
heated ocean upon the earth’s primeval crust before the dawn of life.
The author’s researches into the composition and structure of the
crystalline rocks, conjoined with his studies of the chemistry of
natural waters, led bim, in 1860, to reject the hitherto received view
of the epigenic or metasomatic origin of serpentine, steatite, chlorite,
and similar rocks, and to maintain their derivation from silicates
formed by chemical processes and deposited in the water of lakes or
seas. This view he soon after extended to the various other
exceptional rocks found in crystalline formations which it was, in
1864, asserted had been ‘formed by a crystalline molecular re-
arrangement of silicates generated by chemical process in waters at
the earth’s surface.” In elucidation of this view the author referred
to the insoluble silicates now separated in the evaporation of many
natural waters, to the formation from the earliest times to the present
of deposits of serpentine, sepiolite, glauconite, and of aluminous
silicates allied to chlorite, which are found either forming beds or
filling the cavities of various marine organic forms, from the fora-
minifers of to-day to the crinoids of Paleozoic time, and the EHozoon
of the Laurentian. The formation in modern times of crystalline
zeolites and quartz in thermal waters was also cited in illustration
of this view of the generation of various mineral silicates by causes
now in operation which, it is believed, were far more active in
Eozoic times. This was not, as had been already suggested by
others, a process confined to a seething primeval ocean before the
advent of life, but was continued through long ages under varying
chemical conditions, and was contemporaneous with the deposition

470 Notices of Memoirs—Dr. T. Sterry Hunt—

of successive strata of limestone and detrital matters. The argil-
laceous portions of these, it is conceived, may have taken part in the
reactions with thermal waters. We have thus, in the opinion of the
author, a reasonable mode of accounting for the origin of the various
rocks of the crystalline formations, and a consistent and complete
Neptunean theory which does not involve the aid of metasomatosis.
It has, since it was proposed eighteen years ago, met with the
approval of many whose studies have made them the fittest judges
of its reasonableness. Among those who have either formally given
their adhesion to it, or have enunciated similar views, may be
mentioned the names of Delesse, Renard, Giimbel, Credner, Alphonse,
Favre, and Gastaldi.

The chemical activities concerned in the production of the various
silicates have doubtless suffered gradual change and diminution
through the successive ages of Hozoic time, from which have re-
sulted mineralogical and lithological differences in the crystalline
terranes. Hach of these includes quartzites and limestones, in
which latter certain silicates, such as serpentine, hornblende, and
micas, are occasionally found. It is in those aluminiferous rocks,
which are without lime or magnesia, that are seen the essential and
characteristic differences dependent, as long ago pointed out by the
author, upon a decrease in the proportion of alkalies. As we pass
from the older to the younger of the Hozoic terranes, the felspar,
orthoclase, and albite become partially or wholly replaced by
silicates like muscovite, damourite and paragonite, and finally by
andalusite, fibrolite, cyanite, and pyrophyllite. The author alluded
briefly to the changes by which the ancient aqueous deposits were
transferred into crystalline stratified rocks by what Giimbel has
designated as diagenesis, as distinguished from their supposed origin
by epigenesis or metasomatic change. The question of the relation
of the indigenous rocks to the endogenous and exotic masses in-
cluded in them was noticed, the author alluding to the hypothesis
which he has elsewhere maintained that the source of all exotic or
eruptive rocks is to be found in the displacement or extravasation
of ancient deposits of Neptunean origin.

Coming to the second division of his subject, the author asserted
that the study of the crystalline rocks of North America shows the
existence of several distinct groups or terranes. The Laurentian, which
is the most ancient, includes in its lower part a mass of unknown
thickness of granitoid gneiss, often hornblendic (Ottowa gneiss),
succeeded, perhaps unconformably, by what has been called the Gren-
ville series, consisting of similar gneisses and hornblendic rocks, with
intercalated quartzites and iron ores. These two divisions make up
together the Lower Laurentian of Logan, of which the thickness in
Canada may greatly exceed 20,000 feet. The Norian, which is the
Upper Laurentian, or Labradorian of Logan, rests unconformably
upon the Laurentian, and is remarkable for a great development of
rocks composed chiefly of Labradorite, or related plagioclase fel-
spars, which have been called Labradorite-rock, or Norite. The
interstratified gneisses, quartzites, and limestones of the Norian are

Origin of the Crystalline Rocks. 471

not unlike those of the Laurentian. This series, which abounds in
great beds of titanic iron-ore, has a volume which may exceed the
thickness of 10,000 feet assigned to it by Logan. The Laurentian is
in many parts overlaid by the Huronian series, which is charac-
terized by a great development of greenstones, generally horn-
blendic, with epidote, chlorite, steatite, serpentine, and soft hydrous
mica-schists, often called talcose, besides argillites, quartzites, and
limestones, generally magnesian. It abounds in metalliferous
deposits, including magnetic and specular iron-ores, chrome, and
sulphurets of copper, iron and nickel, and has assigned to it in
different regions a thickness of from ten to twenty thousand feet.

In many parts of North America there exists a great development
of rocks characterized by the predominance of orthofelsite, or petro-
silex, often becoming a quartziferous porphyry. This, which is
apparently the helleflinta of Sweden, was regarded as eruptive until
in 1869 the author showed it to be a stratified series with some
associated quartzites and schists, and then included in the lower part
of the Huronian. Hitchcock, who has since studied these rocks in
New Hampshire, has called them Lower Huronian. From their
absence in many localities at the base of the typical Huronian, it is
conjectured that they may belong to a more ancient and distinct
series. The Montalban, or White Mountain series, is characterized
by micaceous gneisses, generally called granites, which pass into
quartzose and felspathic mica-schists, often abounding in garnets,
staurolite, fibrolite and cyanite. Great masses of dark green gneiss-
oid hornblendic rock, very distinct from the Huronian greenstones,
abound in the Montalban, which also includes beds of a very
peculiar olivine-rock, beside quartzites and crystalline limestones.
This series abounds in endogenous granitic veins, containing muscovite,
beryl, tourmaline, apatite, and oxide of tin. It probably equals the
Huronian in thickness, and is supposed to overlie it. The Taconian
series includes a great volume of characteristic mica-schists, often
quartzose, but seldom distinctly felspathic, and frequently con-
sisting in large part of damonite, or of pyrophyllite. Some of these,
like the schists of the Montalban, include garnet and chiastolite.
They are associated with quartzites, and with dolomites and lime-
stones, all of which are also frequently micaceous. Associated with
these are found serpentines and granular hornblendic rocks of a
peculiar type, very unlike those of the preceding groups and much
less crystalline. The quartzites are in large part detrital rocks.
This series, which yields the statuary marbles of North America,
has a thickness of about 5,000 feet, and is the Lower Taconic of
Emmons. It is found reposing alike on the Laurentian, Huronian,
and Montalban, and is overlaid, in apparent unconformity, by the
Upper Taconic, which is identical with the Quebec group of Logan.
This, which consists of many thousand feet of sandstones and
argillites, with some limestones, includes among its strata organic
forms belonging to various divisions of the Cambrian up to the
Arenig. The Taconian, although containing an undescribed unguloid
shell, and a so-called Scolithus, is, by the author, considered pro-

472 Notices of Memoirs—Dr. T. Sterry Hunt.

visionally as distinct from the Cambrian. It has yielded in Ontario,
besides Scolithus, the Hozoon Canadense, and may, perhaps, be
regarded as the connecting link between the Hozoic and Paleozoic
ages.

The Upper Taconic, or so-called Quebee group, in Hastern North
America, is separated by a stratigraphical break from the succeeding
portion of the Cambrian, the Bala group (Trenton, Utica, and
Lorraine) ; while, on the contrary, the supposed discordance in the
regions just mentioned at the summit of the latter, corresponding to
the division between Cambrian and Silurian in Wales, appears to
have been based on a misconception. There is, however, an
important paleeontological break at this horizon connected with a
ereat deposit of barren detrital rocks, which marked the close of the
Cambrian period, and the author records his opinion that the name
of Lower Silurian, as well as that of Siluro-Cambrian, which he,
with others, has applied to the Bala or upper division of the Cambrian,
is to be rejected as being historically incorrect, and as tending to
perpetuate false views of the paleontological relations between these
and the succeeding rocks. The early advocates in North America of
the notion of the metamorphism of Paleozoic rocks taught, in the
first place, the stratigraphical equivalence of the Taconic, or L. and
M. Cambrian, with the U. Cambrian, and further maintained that
these rocks had suffered various degrees and kinds of metamor-
phism, as the result of which they had assumed, in different areas,
the characters of the Taconian, Montalban, Huronian, and Lauren-
tian; the lithological differences between these several series being
regarded as marks of the greater or less alteration which it was sup-
posed these uncrystalline Cambrian sediments had undergone. Other
geologists have imagined portions of these same crystalline formations
in North America to be altered strata of Silurian, Devonian, and
even of Triassic age. The great groups of Eozoic rocks already
described constitute, however, in the author’s opinion, as many great
stratified series, which, before the Cambrian time, existed in their
present crystalline condition, and had been successively subjected to
the accidents of uplift, contortion, and denudation, so that the newer
Hozoic groups were, at the beginning of the Paleeozoic period, distri-
buted irregularly over the floor of fundamental Laurentian gneiss.
These various crystalline groups are found, with a singular persistence
and uniformity of ethnological character, from Alabama to Newfound-
land, along the Atlantic belt, and thence westward through Canada,
to the great lakes, and beyond, in the vast region of the Cordilleras
to the Pacific slope. The author had some years since pointed out
the remarkable similarity between the various crystalline groups of
North America and the crystalline rocks of the British Islands, and
had lately been able, by new observations, to confirm his conclusions.
Among the crystalline formations of Donegal he had indicated repre-
sentatives of Laurentian, Montalban, and Huronian, and the latter he
had recently observed largely developed in Argyleshire and Perth-
shire. To the Huronian, also, he refers the green schists of Anglesea
and Carnarvonshire, in both of which regions the orthofelsite, or

Notices of Memoirs—Papers read at British Association, 473

helleflinta series at the base of the Huronian (the so-called porphy-
ries), and likewise the more ancient gneisses, are well represented.
He would, however, leave this subject to his friend, Dr. Henry
Hicks, who has so happily mastered the obscure problems of the pre-
Cambrian geology of Wales. The studies of Gastaldi and others
enable us to assert that similar series of ancient rocks occur in the
same order in the Alps; and we infer that the chemical and physical
conditions which presided over the production of the crystalline
stratified rocks were world-wide.

XJ.—British AssocraATION FOR THE ADVANCEMENT OF SCIENCE,
Forty-r1gHtH Meeting, Dusiin, Aucust 141TH, 1878.

A.—Tittes or Papers Reap in Szction C. (Guoxocy).
President.—Joun Evans, D.C.L., F.R.S. .

The President’s Address. (See p. 411.)

Prof. E. Hull, F.R.S.—Sketch of the Geology of the Environs of
Dublin. (See p. 457.)

J. Nolan, M.R.I.A.—On the Ancient Volcanic Districts of Slieve
Gullion. (See p. 445)

W. Mattieuw Williams, F.R.A.S., F.C.S.—Notes on the Glaciation of
Ireland and the Tradition of Lough Lurgan.

W. Hf. Baily, M.B.L.A., F.G.S.—Notice of some additional Labyrin-
thodont Amphibia and Fish from the Coals of Jarrow Colliery,
near Castlecomer, Co. Kilkenny.

W. Pengelly, F.R.S.—On the Exploration of Kent’s Cave. Four- —
teenth Report. _

R. H. Tiddeman, M.A., F.G.S.—Sixth Report on the Victoria Cave,
Settle.

Prof. Alexander Macalister, I. D.—Report on Fermanagh Caves.

C. HE. De Rance, F.G.S.—Fourth Report of Committee on Under-
ground Waters. (See p. 462.)

W. Pengelly, F.R.S.—On the relative Ages of the Raised Beaches
and Submerged Forests of Torbay.

Isaac Roberts, F.G.S.—Experiments on Filtration of Sea Water
through Triassic Sandstone.

V. Ball, M.A.—On a new Geological Map of India.

Prof. W. C. Williamson, F.R.S.—On the Supposed Radiolarians of
the Coal-measures. (See p. 461.)

The President.—On some Fossils from the Northampton Sands.

W. H. Baily, F.G.S.—On some Irish Fossils.

J. Nolan, M.R.I.A.—On the Metamorphic and Intrusive Rocks of
Tyrone.

T. Sterry Hunt, F.R.S.—On the Origin and Succession of the
Crystalline Rocks. (See p. 466.)

H. Hicks, U.D.—On some new pre-Cambrian Areas in Wales. (See
p- 460.)

W. Williams.—On the Cervus megaceros.

W. A. Traill_—The Rocks of Ulster as a source of Water Supply.
(See p. 463.)

474 Notices of Memoirs—Papers read at British Association.

J. W. Davis.—On the Occurrence of certain Fish Remains in the
Coal-measures, and the evidence they afford of the freshwater
origin of the Coal-measures.

G. A. Lebour.—On the Discovery of Marine Shells in the Gannister
Beds of Northumberland.

R. A. C. Godwin-Austen.—Report on proposed Kentish Explorations.

W. Jolly, H.M.I.S.—Report on Fossils of the N. W. Highlands of
Scotland.

E. T. Hardman, F.C.S.—On the Influence of Strike on the Physical
Features of Ireland.

EL. T. Hardman, F.C.S.—On Hullite ; a hitherto undescribed Mineral,
with Notes on the Microscopic Appearances, by Prof. Hull,
F.RS. (See p. 464.)

Prof. Hull, F.R.S.—On the Progress of the Geological Survey of
Ireland. (See p. 464.)

Rev. H. W. Crosskey.—Report of the Committee on Erratic Blocks.

Dr. T. Sterry Hunt, F.R.S.—On the Geological Relations of the
Atmosphere.

Prof. Herschel.—Report of Committee on the Conductivity of Rocks.

Prof. W. King, D.Sc.—On the Age of the Crystalline Rocks of
Donegal. (See p. 465.)

Prof. E. D. Cope.—On the Saurians of the Dakota Cretaceous Rocks
of Colorado.

Prof. James Nicol, F.R.S.E.— On some New Fossils, Hribollia
Mackay, trom the Quartzites of Loch Eriboll and other parts of
the Western Highlands of Scotland.

Alphonse Gages, M.k.I.A.—On the Influence that Microscopic Vege-
table Organisms have on the Production of Hydrated Iron Ores.

Prof. O Reilly, M.R.I.A.— On the Correlation of Lines of Direction
on the Globe, and particularly on Coast Lines.

Rev. Prof. Haughton, M.D., F.R.S.—On the Earth’s Axis.

Rev. Maxwell H. Close, F.G.S.—Concerning the Extent of Geological
Time. (See p. 450.) :

C. E. De Rance, F.G.S., and Captain R. A. Feilden, R.A.—Geological
Results of the late British Arctic Expedition.

B.—Tirtes or Papers, Bearinc upon Grotocy, READ IN OTHER
SECTIONS.

Joseph Lucas.—On the Hydrogeological Survey of England. (Sec-
tion G.

Sir Victor Brooke, Bart.—On certain Osteological Characters in the
Cervide and their probable bearings on the past History of the
Group. (Section D.)

W. Morris.—On the Temperature of the Earth within. (Section A.)

Prof. Henry Hennessy.—On the Limits of Hypotheses regarding the
Physical Properties of the Matter of the Interior of the Harth.
(Section A.)

I. Roberts.—The Filtration of Salt from Sea Water into Wells in the
Trias Sandstone. (Section G.)

Reviews—Daris’ and Lees’ Geology, etc., of W. Yorkshire. 475

REVIEWS.

I.—West Yorksutre. AN Account oF ITs GxonoGcy, PHystcaL
GEOGRAPHY, CLIMATOLOGY, AND Botany. Part I. Gurotoay. By
J. W. Davis, F.G.S. Part I].—Puystcan GroGRaPHy AND
Boranicat Topocrapuy. By J. W. DavisandF. A. Lens. 8vo.,
pp. 414, with two maps and twenty-one plates. (London,
L. Reeve & Co., 1878.)
HE importance of the county of Yorkshire, the large area it
includes, and the number of formations therein represented,
have always rendered it an attractive field to the geologist. The
very mention of Yorkshire calls to mind the names of William
Smith, John Phillips, Buckland, Young, and Bird, and a host of
others, to say nothing of the valuable publications of the Govern-
ment Geological Survey.

The first Survey Memoir having any reference whatever to this
county was published in 1861, and has been followed by a few
others, mostly, however, treating of some limited area, such as a
coal-field, and not covering any large extent of country. The
process of mapping has nevertheless been slowly going on, and
we may hope to be favoured some day with the Survey’s opinions
on the Ridings; or, Yorkshire as a whole.

A door has thus been left open in the mean time for others to
supply the growing want felt here, as elsewhere, of a more general-
ized treatise than is afforded by these detached memoirs. Accord-
ingly, in 1868, Mr. J. G. Baker published a work on North
Yorkshire, and so set an example and furnished a model whereon
to found the work, of which the first volume lies before us.

The portion devoted to geology extends over the first 228 pages,
and appropriates to itself all the plates, and one of the maps for
its illustration.

The first thing one notices on opening the book is an excellent
and extremely interesting “‘ Bibliography,” chronologically arranged,
commencing with a paper published by Lister in 1674, and carried
down to the end of the year 1876. The introductory chapter, which
follows next, is devoted to a sketch of the physical and geological
features of the district. To this succeeds a series of chapters on the
different geological periods to which the various rocks found in it
belong, namely,—Post-Tertiary, Triassic, Permian, Carboniferous,
Devonian (?), and Silurian. They are taken in ascending order, the
Carboniferous, owing to its economic importance, coming in, of
course, for the “lion’s share” of attention. In each case the author
briefly describes the nature and characteristics of the component
beds, giving, when occasion warrants it, details of the more im-
portant sections. With each series of beds we find a list of its
fossil contents, and occasionally a few words as to the probable
conditions under which it was deposited.

The oldest rocks of this area are the Green Slates and Porphyries
of Sedgwick, here classed as Lower Silurian, from which it will be
seen that the author follows Murchison’s classification. We are left

476 Reviews—Davis’ and Lees’ Geology, etc., of W. Yorkshire.

to infer that the beds doubtfully classed as Devonian are certain
“red conglomerates’ at the base of the Mountain Limestone, and
resting in hollows in the Silurian slates below; at all events they
have a chapter to themselves. No fossils have been found in these
conglomerates ‘‘except such as are inclosed in the Silurian stones
it contains.”

The Permians are treated of separately, and the existence of a
considerable break at this locality between them and the Coal-
measures insisted on, though their relation to the overlying Trias is
not mentioned. The red and purplish-red Plumpton Grits, hitherto
classed as Permian, are now,-on the authority of the Geological
Surveyors, relegated to the Millstone Grit series, which is here imme-
diately overlain by the Permian beds.

Arrived at the Trias, we become aware of a slight change in the
method of treating the component beds, for both the list and de-
scription are in descending order. In the preceding formation the
list was in descending order, the description in ascending; whilst in
the Silurian and Carboniferous both lists and descriptions are in
ascending order. Variety, though charming, may prove sometimes,
as in the present instance, rather confusing.

The fashionable ‘Glacial Period,” which follows on the Trias, is
fully dealt with, and we read of a “great glacier” 1500 to 2000
feet thick, and of another ‘eight miles broad and at least 700 or
800 feet deep.” These ice-giants do not appear to have troubled
themselves about excavating lake-basins ; but merely to have passed
their time in scratching the rocks over which they passed, and in
transporting huge rock fragments from place to place. Some re-
markable examples of erratic blocks of Silurian age that have been
stranded on the Mountain Limestone of Norbar, near Clapham, are
figured on plates xiv. and xv. The Drift deposits are very irre-
gular in their mode of occurrence; thus, ‘‘on the synclinal south-west
of Carlton, drift is exposed at Park Head Quarry at a height of
1050 feet; other parts of the same synclinal at a height of not
more than 600 feet are devoid of drift. As a rule the thickest
deposits are in the valleys and on low grounds; they are thinner on
the hill-sides, and either very thin or absent on the grit and lime-
stone ridges which usually form the summits of the highest hills.”

With the succeeding Post-Glacial beds the first part closes, and
we start over the ground afresh with an eye to its physical geo-
graphy and topographical botany, especially the latter. Omitting
the long list of botanical names, it is, from its very nature, far more
“readable” than the foregoing.

The plates, which bring up the rear, are diagrammatic rather than
elaborate, and are well suited to the purposes for which they are in-
tended. One can only wish that a few more had been added giving
views illustrative of the different landscape effects produced by the
several formations, as in the Survey publications. The maps, stowed
away in pockets in either cover, are on a scale of 4in. to the mile,
and carefully finished. The geological one will certainly, as Mr.
Davis hopes, “be of service to practical geologists, the more so that

Reviews—Felix Karrer on the Vienna Aqueduct. 477

it embraces districts for which the Survey Maps are not yet pub-
lished’? ; whilst the work itself will be heartily welcomed by all,
the completion of the second volume looked forward to, and doubt-
less not a few will wish that yet a third may be added that shall
comprise the Zoology of this interesting district. BoB We

JI.—Tur Grotoey or tHE Emperor Francrs-Josepa’s AQUEDUCT AT
Vienna. A Stupy or tHE Tertiary Formations oN THE WEST
Fuank or THE ALPINE Portion OF THE NEIGHBOURHOOD OF VIENNA.
(GroLogtn DER Katser Franz Josers Hocu-QuELLEN-WASSER-
LEITUNG. Hinze Stuprsg, etc.) By Frnrx Karrer. With Twenty
Plates, and numerous Illustrations in the Text. Published for
the Imperial Royal Geological Institute. 4to. 420 pages. (A.
Hoélder, Vienna, 1877.)

die is a very fine large volume, brought out by the Austrian

Geological Survey, at the expense of the State, and elaborated
by the care of that excellent geologist and paleontologist Frnix

Karrer, with the co-operation of Suess, Fuchs, Jellinek, von Sacken,

Teller, and many other friends, whose aid he acknowledges in the

preface.

The great Aqueduct lately constructed to supply Vienna with
water from the Kaiserbrunnen, distant 11% Austrian miles, and the
Stixenstein Springs, about 94 Austrian miles from the main reservoir
at the Rosenhiigel, and thence by pipes into the city, is the subject of
this noble a The nature and localities of the sources, and the
topographical features and geological structure of the ground, are the
main objects in view, besides the gradients and the engineering and
architectural characters of the actual works, as conduits and chambers
at the springs, open channels, tunnels, bridges, and reservoirs.

The geology of the Vienna Basin is treated of in a general way in
the Introduction ; and a valuable list of books and memoirs bearing
on the subject, from 1500 to 1875, is appended. Additions to this,
down to 1876, are given in the Appendix, at p. 403. The twelve
large plates of well-drawn sections, illustrating the line of the
Aqueduct, with their associated plans and sketches of the country,
elucidate the physical geography very clearly ; and the fine geologi-
cal map, by Th. Fuchs, of the neighbourhood of Vienna, including
the Rosenhiigel, and forming pl. 19 (published also in vol. ix. of the
Transactions of the Geological Institute of Vienna), adds greatly to
the value of the work.

The formations traversed by the Aqueduct from the Kaiser-
brunnen on the §.W. (191°80 Vienna fathoms above the Danube
water-mark at Vienna) to the Rosenhiigel on the N.E. (46°28), on
which the main reservoir is situated, comprise Post-Tertiary—
Alluvium and Diluvium; Tertiary—the Congeria-beds, the Sar-
matian beds, the Mediterranean beds; Triassic—the Upper Trias
or Wetterstein-limestone, the Guttenstein-limestone, the Werfen-
schists ; Older Rocks—Grauwacke-schists.

The Triassic rocks come to- day at the Kaiserbrunnen, resting
on old schists, in which the valley of the Schwarza is here cut for
some distance. Congeria-beds succeed as far as Ternitz, where the

478 Reviews—Leonhard and Geinitz’s Neues Jahrbuch.

broader valley is mostly coated with alluvium. ‘Tertiary deposits
are again met with when the Aqueduct takes the hill-sides towards
Baden, where there is an exposure of the Triassic limestone,
surrounded with the Mediterranean Tertiaries. At Médling the
Trias is seen, with gypsum; and the Sarmatian Tertiaries form
most of the ground to the Rosenhiigel, beyond which the ground
falls, for about half an Austrian mile, to the valley-deposits of the
present river.

The branch Aqueduct from Stixenstein (160-77 Viennese fathoms
above the Danube, and 93 Austrian miles from Vienna) begins on
Triassic limestones and schists, and follows the valley-deposits of
the local stream, to join the main line at Ternitz.

Besides containing many maps, plans, and diagrams, the text is
enriched with nearly a hundred numbered vignette sketches, mostly
geological, giving the local details of numerous well-executed
sections, supplemental to the longer sections on the plates.

The description of the Aqueduct and the ground traversed by it
is given in chapters according to the successive segments. ‘The
geology, including the paleontology, is fully given, together with
references to all the authors and workers who have originated or
added to what is known of each locality.

The quantity, temperature, and constitution of the waters of the
localities concerned are carefully noted and in many cases tabulated.
The thermal area of Baden, and the artesian wells of Atzgersdorf,
have special mention and maps.

Various objects of antiquity were discovered in the course of the
works. ‘Those from an ancient cemetery (of the Bronze Period) at
Leobersdorf, are particularly described and illustrated (pls. 17 and
18), by Baron von Sacken ; and some pre-historic skulls, from the
same place, by F. Teller. Besides the geological descriptions,
sections, and maps, with which this work on the Vienna Aqueduct
abounds, we must especially mention the beautiful illustrations and
careful definitions of new species of fossil Mollusca and Fora-
minifera (pls. 16a and 16), with which Theodor Fuchs and Felix
Karrer have enriched this magnificent volume, which in every
respect worthily represents the liberality of an enlightened State,
and the industry and knowledge of enthusiastic and conscientious
geologists, both within and without the offices of the Survey, of
whom the Imperial Government may well be proud.—T.R.J.

Ill.—“ Neves JaAuRBucH FUR MINERALOGIE, GEOLOGIE UND PALz-
ONTOLOGIE,” founded by K. C. von Luonnarp and H. G. Brown,
continued by G. Lzonnarp and H. B. Geinirz. For the years
1876, 1877. 8vo. (H. Koch, Stuttgart.)

HIS well-sustained periodical continues to supply us with the
Ah results of the scientific industry of Germans and others who
studiously work at rocks, minerals, and fossils in the field and in
the laboratory. As usual, there are not so many memoirs devoted to
physical geology and paleontology as to mineralogy and petrology ;
and the current correspondence shows, also, that the several fields
of mineralogical study are closely cultivated by the larger number

Correspondence—Rev. E. Hill. 479

of students. But this may well be in a country largely constituted
of altered and igneous rocks, and among students who have reason
to look for evidence of geological history as well in the original
conditions and successive changes of rock-material as in the
character and position of organic remains. The valuable abstract
notices of contemporaneous books and memoirs treating of geology
and mineralogy are abundantly and carefully given as heretofore.

CORRESPONDENCE.

THE POSSIBILITY OF CHANGES OF LATITUDE.

Str,—The question discussed in the article on Changes of Axis in
the June Number of this MaGazine was,—‘“ The earth being rigid,
could a deformation tilt the axis in space, or shift the position of
the Poles?” The answer was that a tilt was impossible and a shift
improbable. Mr. Fisher, in the July Number, asks for a discussion
of the question—‘ Assuming that a thin crust surrounds a fluid sub-
stratum, could then a deformation shift the crust over the nucleus ?

An obvious reply is, that if the Earth’s rigidity has been proved,
the discussion would be fruitless. Mr. G. H. Darwin, who has been
investigating this point, concludes that the Earth is “ enormously
stiff” (Proc. Royal Soc., No. 188, 1878).

However, the nature and consequences of the objection to Dr.
Hopkins’s demonstration may be noticed. His argument was in
effect that if there existed a very large fluid nucleus, since the shell
would slide freely over it, the Harth’s crust could not oppose to the
tilting forces so great a resistance as we find from the amount of
Precession that it does oppose. To this it is now answered that if
the fluid nucleus be spheroidal and rotating, it would resist the
tilting force which produces Precession, and the shell would not
slide freely. But then would it not also resist the tilting tendency
resulting from a deformation? If Dr. Hopkins’s proof from Pre-
cession collapses, does not also the supposition become untenable
that a fluid nucleus would render easy a shift of the crust? The
suggestion of a fluid substratum seems to lead to the same dilemma;
either the fluid could resist any shift of the crust, or it could not,
and so Dr. Hopkins’s disproof remains valid.

A question prior to all this is, Will a change in Latitudes give the
best explanation of the phenomena ? E. Hr.

St. JoHn’s CoLLEGE, CAMBRIDGE, August 22nd.

GEOLOGICAL TIME.

Str,—The great difficulty encountered by the geologist, in re-
ducing a section of Geological Time to years, from the want of data,
is so well known, that bringing the following before your readers
may be pardoned, as an attempt to measure a small section of time.

In the parish of Beith, North Aryshire, the Lower Carboniferous
Limestone is extensively wrought as a surface stratum. In some
quarries the limestone is preserved by a thick covering of Boulder-
clay, and here the surface is ice-polished and finely striated, retaining

480 Correspondence—Mr. Rk. Craig—Ur. W. H. Penning.

the same features as when the ice-grinding stopped. In other
quarries, where the covering is loose, the limestone is eroded into
pits, swallow-holes, and crevices, many feet in thickness being often
dissolved away altogether. For a long time I have been on the
outlook to find a section that would give the number of feet
destroyed by sub-aérial erosion since glacial action ceased, but failed
until lately. It was always easy enough to know how many feet had
been removed as a whole, but there was no data to show where glacial
action had stopped, and sub-aérial erosion had commenced. How-
ever, a section has been laid open that gives a close approximation.

In the upper half of this limestone various bands of nodular flint
occur, three of which bands are prominent; and are divided from each
other by five feet of intervening limestone, and lesser flint bands.
In one section, where about 20 feet of limestone had been removed
by erosion, the three flint bands were found nearly entire, while the
limestone was gone. It was therefore clear that all of it, from,
at least, the upper flint band, had been destroyed by such sub-aérial
erosion since glacial action stopped—the minimum quantity eroded
cannot be less than twelve feet, probably as much as fifteen feet.

Having measured the rate of erosion for thirty years, by taking
the limestone surface with a plastic substance, and replacing the loss
through erosion with water, and thus calculating the loss, I find
from this, that it is being denuded at the rate of 5 of an inch in
fifty years, or one foot in 9600 years. If this be anything
approaching an average, it would take 115,000 years to denude
twelve feet, or 144,000 to reduce fifteen feet, the probable quantity
destroyed.

This gives an approximation of the time that has passed away
since glacial action stopped, and sub-aérial erosion commenced.
Still a considerable period may have been taken up in denuding
clay left by the ice; but on this I do not enter, farther than to say
that the section being on a very small plateau, on a water-shed, and
I believe that very little Boulder-clay would be left upon it, and
that sub-aérial erosion would commence shortly after glaciation had
stopped. Rozsert Craig.

LanesipE, Briru, Sept. 4th, 1878.

THE DIVINING ROD.
Sir,—The following extract from the Marlborough Times of
Aug. 24th should possess great interest for readers of the Grou. Mac.
Lonpon, 6th Sept., 1878. W. H. Pennine.

SrarcH FoR Warer.—A person from Colerne, near Bath, who professes to have
the gift of divining where a spring of water is to be found by means of a small
piece of white thorn of this year’s growth in the shape of a V, was at Wootton
Bassett the other day and operated on Mr. Hart’s premises, pointing out a site for
another well for his brewery—even the depth at which water would be likely to be
found being designated by him. It is said that those who possess this quality are
extremely few. Two or three years since a person named Weare resided in the
town who used the divining rod, and who had a most implicit and sincere belief in
his powers, for which he could not account, and really to a looker on the rod
appeared to move quite independently of him and in fact to be beyond his control.
The operator on this recent occasion stated, we believe, that he had been successful
in discovering springs by this means on more than two hundred occasions without a
single failure. (!)

My, VLE Y
Us, MY

tf

THE

GEOLOGICAL MAGAZINE.

NEW SERIES: DECADE “ih sVOLE. Vv.
No. XI—NOVEMBER, 1878.

(@psvih SC ALINfYNaby weer Sy dha OpaniaysS)-

J.—Emrnent Livine Gronocists. (No. 3.)

Proressor JoHN Morris, M.A. Cantab., F.G.S.,: ete.; 1
President of the Geologists’ Association.

(Wirx a Porrratt.) -

HERE are left to us at the present day but a few of those
naturally-gifted masters in science whose career may be fitly
likened to that of the illustrious Faraday; to this type of man
belongs Professor John Morris among geologists. Though occupying
a modest position in society, and possessing but few of the advantages
which the world offers, Professor Morris has achieved for the science
of his choice a vast amount of popularity and recognition; and
during a long career he has by his eloquence, his unassuming
manner, and straightforward, earnest, and warm-hearted friendship,
exercised a powerful influence over all with whom he has been
brought in contact.

Professor Morris was born at Homerton, near London, February
19th, 1810. His father, Mr. John Morris, was a timber-merchant
in the City of London, and his son is a Freeman of the Wheelwrights
Company and a Freeman and Liveryman of the Turners Company,
and Citizen of London, of which his father also was a Citizen. His
early education was received at a private school at Clifton, near
Nuneham, Berks, and afterwards at Parson’s Green, Fulham. His
first ideas of science were derived from some occasional lectures
delivered at the Clifton School, from which he imbibed an ardent
interest for Astronomy; one of his earliest papers being entitled,
«A Few Observations on the Aurora Borealis visible at Kensington,
on the evening of Oct. 5, 1836” (Mag. Nat. Hist., 1836, p. 574).

For many years he was engaged as a Pharmaceutical Chemist in
Kensington, but although devoting part of his time to business, he
was from a very early date (as his published papers demonstrate)
ardently addicted to scientific pursuits, which in time engrossed all
his thoughts.

So early as 1836, Mr. Morris began to collect materials for a
Catalogue of British Fossils. Previous to this date, the only work
available for the student in this country was “A Synoptical Table of

' We perhaps owe an apology to our coadjutor for publishing in our pages the
above memoir, but he will, we doubt not, give us his indulgence when he knows that
our imperfect record will gratify a large circle of friends who entertain for him the
warmest regard.—Eprr. Grou. Mac.

DECADE II.— VOL. V.—NO. XI. 3 : 31

482 Eminent Living Geologists—Prof. John Morris.

British Organic Remains,” published in 1830, by Samuel Woodward,
of Norwich. This well-known geologist, however, died in 1837,
and his second son, Dr. 8. P. Woodward, at that time a youthful
assistant under Mr. William Lonsdale, in the Museum of the Geo-
logical Society, not attempting to bring out a new edition of his
father’s book, the task of supplying geologists with a work meeting
this desideratum devolved upon Professor Morris.

Whilst engaged in preparing this catalogue, he published a
valuable series of preliminary notes in the Magazine of Natural
History for 1839. These were continued, section by section, for
some time previous to the appearance of the first complete edition
of the Catalogue in 1845.

Tn recognition of the task upon which he was engaged, the Council
of the Geological Society awarded Mr. Morris the Balance of the
Proceeds of the Wollaston Fund for 1842 and 18453.

The second edition of Morris’s Catalogue appeared in 1854, the
Council again recognizing the importance of the work by the award
of the Wollaston Fund in 1850 and 1852.

We believe it is the intention of the author shortly to publish a
third edition, for which he has long been engaged in accumulating
materials.

This Catalogue may be placed among the most important contri-
butions to modern geology. It is far from being a mere compilation,
as every one who has worked with it can testify. Every group,
every genus, every species, was made the subject of exact study,
and in each department the specialist is surprised to find the advanced
views of this great master in Paleontology. This work, with its
wonderful accuracy in detail, has contributed largely to the elabora-
tion of stratigraphical geology by supplying the life-data so necessary
for such a task.

In the year 1855, after two geological tours through Hurope, in
1853 and 1854, with Sir Roderick J. Murchison, Professor Morris
was induced by that eminent geologist to offer himself as a candidate
for the Chair of Geology in University College, to which he was
appointed, and which he continued to hold until June, 1877,—a
period of 22 years,—when the Rev. T. G. Bonney, M.A., F.RS.,
was elected to succeed him. During this time Baron Goldsmid gave
a small endowment to this Chair, which thenceforward bore his
name. Mr. James Yates, M.A., F.R.S., also took a warm interest
in Geology, and bequeathed a handsome sum for the same purpose,
to be available after the death of Mrs. Yates.

But few are aware of the amount of preparation required and
mental wear and tear sustained by a scientific man holding the office
of Professor. During his occupation of the Chair of Geology
Professor Morris delivered over 1100 lectures to his class, besides
directing field-excursions and giving demonstrations in the Museum.

Tn addition to these lectures he delivered courses of lectures at the
Royal Agricultural College, Cirencester ; the Natural History Society,
Newcastle; the Yorkshire Philosophical Society; the Birmingham
Natural History Society ; the London Institution ; the Royal Institu-

Eminent Living Geologists—Prof. John Morris. 483

tion, and the Croydon Microscopical Society. For many years he
lectured at the Coal Exchange before the Coal Factors Society, on
“Coal and Coal Mining”; and for two years he acted as Deputy-
Woodwardian Professor of Geology in the University of Cambridge,
for his old friend Professor Sedgwick. Between 1870 and 1872, and
from 1877 to the present time, he has filled the office of President of
the Geologists’ Association, and for many years he has been ac-
customed to lead the country excursions of this Society in almost
every district in England, ever ready in the Field as in the Class-
room, to impart valuable and timely information, and elucidating the
geology of each district visited with untiring energy and good will.

His printed papers are fewer in number than would have been
expected from so able and experienced a geologist and palzontolo-
gist, but they are of extreme value, from the large and philosophical
views which the author takes of the subjects treated on, and for the
careful and extensive bibliographical references they always contain,
doing full justice to his predecessors.

He has been a most constant and diligent student of the current
literature of geology, ever adding new facts to his store of know-
ledge. But he has a strong antipathy to appear in print, and much
of his knowledge would inevitably be lost to science were it not for
the fact, that he is always ready to communicate information to in-
quirers. He is moreover so indifferent to the matter of receiving
recognition, that many of his views have become common property.

We have heard one who has frequently acknowledged publicly
his indebtedness to Professor Morris, say, that it was often difficult
for him to distinguish what was his own work, and what he owed to
Prof. Morris, seeing that the Professor so freely communicated his
knowledge in conversation, that it became incorporated with the
author’s own store, and there being no written or printed record to
appeal to, it was difficult to determine where the obligation began
or ended. Many, we believe, could bear similar testimony.

But it is not alone in Geology and Paleontology that Professor
Morris has proved himself an efficient master; among his varied
acquirements must specially be mentioned his extensive and accurate
acquaintance with Mineralogy, upon which science he gave regular
lectures and demonstrations in University College. Nor is his ac-
quaintance with practical Mining and Metallurgy less remarkable. A
disinclination to engage in mercantile mining operations has, how-
ever, debarred Professor Morris from accepting many remunerative
professional offers, which, “taken at the flood,” might have “led
on to fortune”; but Fortune’s wheel was never the ambition of
Professor Morris’s life—his greatest happiness has been derived from
traversing some well-exposed geological section, and explaining its
salient features to an eager and willing class of students.

Honours, well- earned, have been bestowed upon Professor Morris,
and testimonials of a more substantial nature have not been wanting
to express appreciation of his services to science.

On July 14, 1870, a meeting (at which nearly a hundred gentlemen
occupying prominent positions in geological science and in mining

484 Eminent Living Geologists—Prof. John Morris.

were present) was held at the Apartments of the Geological Society
in Somerset House, presided over by Sir Roderick J. Murchison,
Bart., K.C.B., F.B.S., to present to Professor Morris an address on
vellum (indited by the facile pen of the late Prof. John Phillips,
F.R.S., of Oxford), accompanied by a sum of over £600, as a testi-
monial of the high appreciation in which his scientific labours were
held by his numerous friends.

At the Anniversary Meeting of the Geological Society, February
18th, 1876, the first award of the Lyell Medal and Fund was (by
a unanimous vote of the Council) made to Professor Morris. In
presenting the medal, the President, Mr. John Evans, D.C.L., LL.D.,
I’.R.S., said, after referring in laudatory terms to Professor Morris’s
Catalogue and published papers on Geology :—“ Your lectures have
done much to spread a taste for Geology, and to enlarge the number
of its students; and those who have heard you take part in our
discussions must have been astonished alike at the minuteness of
your knowledge of every branch of Geology and Paleontology, and
at the powers of memory by which you were enabled to apply it.”

On the 7th of February, 1878, Prof. Morris was admitted to the
Freedom and Livery of the Turners’ Company of the City of London,
“‘in consideration of his eminence in the science that relates to the
structure, composition, and distribution of the mineral substances
employed in the Turners’ Art.”

But probably the honour of which Professor Morris feels most
justly proud is that which he received on the 6th of June last, when
the Senate of the University of Cambridge conferred upon him the
honorary degree of Master of Arts.!

1 The following is the speech delivered by the Public Orator on June 6th, 1878,
in presenting John Morris, F.G.S., late Professor of Geology at University College,
London, for the honorary degree of Master of Arts :—

Dignissime domine, domine Procancellarie, et tota Academia :

In his sedibus priorum seeculorum munificentia doctrine dedicatis atque recentiori-
bus disciplinis melius indies accommodatis, antiqua respicimus et veneramur vetera,
sed idem inter recentiora optimum quidque fovemus et nova (modo vera sint) non
reformidamus. Quanto igitur cultu digna est illa presertim scientia, que ipsa nuper
in ordinem redacta, orbis terrarum explorat antiquitatem, que prioris evi vestigia
saxis Impressa indagatur, que monumenta vetusta rupibus insculpta interpretatur,
quee illas denique rerum species que antiquitus vivebant cum his que hodie
supersunt comparat. Quanta etiam laude vir hic dignus est, qui annos quadraginta,
magnum vitee spatium, illi scientize excolende feliciter impenderit ; qui viginti annos
inter Londinenses professoris munere egregie functus sit; qui nobis denique eo
artiore vinculo sit conjunctus, quod ipse geologorum Britannicorum quotquot nune
vivunt eruditissimus, duo annos illius viri erat vicarius, qui equalium suorum diu
superstes, non recentiorum modo disciplinarum lumen sed prisce etiam virtutis
exemplar nobis preeferebat, Nestor ille noster, Adamus Sedgwick.

Geologie quidem studiosis satis notum est hujus viri magnum illud opus, in quo
tot antique vitee monumenta e rupibus effossa per seriem recensentur; sed omnes
sibi eo presertim nomine obstrinxit, quod neque laudis neque lucri avidus suos fontes
omnibus patere passus est, quodque e sue scientice finibus in illas artes egressus est,
que ad communem vite utilitatem pertinent, illud unice verum arbitratus, scientiam
artis expertem sibi soli vivere, artem scientia nixam universo generi humano magno
in perpetuum esse adjumento.

Jure igitur post tot annos assiduis laboribus deditos professoris emeriti titulo inter
suos ornatus est, felix laborum preeteritorum memoria, felix etiam successore suo ;

Eminent Living Greologists—Prof. John Morris. 485

His own College, on his retirement from the active duties of his
Chair, resolved, in appreciation of his valuable services, to retain his
connexion with the Institution by appointing him “ Emeritus
Professor.”

Professor Morris is also a Foreign Member of the Royal and
Imperial Geological Institute of Vienna, of the Natural History
Society of Dresden, of the Academy of Natural Sciences, Philadel-
phia, and of the Société Géologique du Nord.

Murchison’s name is inscribed on a tablet in Bavaria’s Walhalla ;
though the name of his early and life-long friend may never find a
place there, it will ever be a household word to geologists, and his
services can never be forgotten by the younger men now actively
advancing the science of geology, many of whom owe so much to
his teaching.

The following is a list of Professor Morris’s scientific papers as
far as we have been enabled to collect them :—

Observations on the Strata near Woolwich.—Mag. Nat. Hist. viii. 1835, pp.
306-367.

On a Freshwater Deposit containing Mammalian Remains recently discovered at
Grays, Essex.— Mag. Nat. Hist. ix. 1836, pp. 261-264.

On some Deposits containng Mammalian Remains at Maidstone, Kent.—Mag.
Nat. Hist. ix. 1836, pp. 593-597.

On some Strata usually termed Plastic Clay (1837).—Geol. Soc. Proce. i. 1838,
pp. 400-462.

On the Coast Section from White Cliff Lodge, one mile south of Ramsgate, to
the Cliff's End, near the “‘ Station Brig” in Pegwell Bay, Kent.—Geol. Soc. Proc.
ii. 1838, pp. 595-596.

Remarks on the Production of Crystals.—Mag. Nat. Hist. 11. 1838, pp. 438-44.

On the Deposits containing Carnivora and other Mammalia in the Valley of the
Thames.—Mag. Nat. Hist. 11. 1838, pp. 5389-548.

A Systematic Catalogue of the Fossil Plants of Britainm—Mag. Nat. Hist. iii.
1839, pp. 452-457, 543-548, iv. pp. 75-80, 179-183.

Remarks upon the Recent and Fossil Cycappm.—Ann. Nat. Hist. vii. 1841, pp.
110-120.

On the Occurrence of the Genus Pollicipes in the Oxford Clay.—Ann. Nat. Hist.
xv. 1845, pp. 30-31.

Description of some New Species of the Genus Ancyloceras.—Ann. Nat. Hist. xv.
1846, pp. 31-34.

On the sub-division of the Genus Terebratula.—Geol. Soc. Journ. i. 1846, pp.
382-389.

Description of a New Species of Nautilus from the Lower Greensand of the Isle
of Wight.—Ann. Nat. Hist. 1. 1848, pp. 106-107.

Observations on Mr. Hancock’s paper on Excavating Sponges.—Ann. Nat. Hist.
iv. 1849, pp. 239-242.

Note on the Genus Stphonotreta, with a description of a new Species (S. Anglica).
Ann. Nat. Hist. iv. 1849, pp. 316-3821; Brit. Assoc. Rep. 1849 (pt. 2), pp. 57-48.

On Neritoma, a Fossil Genus of Gasteropodous Molluscs allied to Nerita.—Geol,
Soc. Journ. vy. 1849, pp. 332-336.

On the Occurrence of Mammalian Remains at Brentford.—Geol. Soc. Journ. vi.
1850, pp. 201-204.

jure a nobis artium magister hodie salutatus, quasi ex alto mari in portum placidum
vectus hac saltem laureola nunc demum coronatur,

ceu presse cum jam portum tetigere carine

puppibus et leeti nautee imposuere coronas.

Ceterum nobis vix necesse est ¢oram illo plura dicere, cui lapides quoque muti
loquuntur; quod si talis viri laudes prorsus tacuissemus, prope ipsa saxa (nisi fallor)
indignabunda reeclamare voluissent.

Duco ad vos Jouannem Morris.

486 Eminent Living Geologists—Prof. John Morris.

Palzontological Notes.—Ann. Nat. Hist. viii. 1851, pp. 85-90.

Description of a Species of Belemnite (Belemnites Bouchardi), with Observations
on Aptychus.—Ann. Nat. Hist. x. 1852, pp. 355-356.

Description of some Fossil Shells from the Lower Thanet Sands (Sanguinolaria
Edwardsii ; Panopea granulata; Pholadomya Koninckii).—Geol. Soc. Journ. viii.
1852, pp. 264-268.

On some Sections of the Oolitic District of Lincolnshire.—Geol. Soc. Journ. ix.
1852, pp. 317-344.

Notes on some Miscellaneous Fossils from the ‘“ Woolwich”? and “ Reading
Series.’’—Geol. Soc. Journ. x. 1854, pp. 157-160.

On the Occurrence of Allophane at Charlton, Kent.—Geol. Soc. Journ. xiii.
1857, pp. 13-17.

British Fossils stratigraphically arraged.—“ Geologist,’ 1858, pp. 188-142, 189-
194, 233-238, 279-286, 319-324. Part I. Silurian Fossils.

Description of the May Hill Limestone.—Malvern Nat. Field Club, Trans. ii.
1858, pp. 4-5.

On a Species of Fern from the Coal-measures of Worcestershire [1858]—Geol.
Soc. Journ. xy. 1859, pp. 80-84.

On Coal; its Geological and Geographical Position.—Geol. Assoc. Proc. i.
1859-63, pp. 170-192.

On Coal-plants.—Geol. Assoc. Proc. i. 1859-63, pp. 289-301.

A Catalogue of British Fossils; comprising all the Genera and Species hitherto
described, etc. London, 1848. 8vo.

Ditto. Second edition, 1854. 8vo. pp. 380.

Descriptions of Fossils from New South Wales and Van Diemen’s Land, in Count
P. E. de Strzelecki’s Physical Description of New South Wales and Van Diemen’s
Land. London, 1845. 8vo. pp. 462.
ae the Occurrence of Grey-Wethers at Grays, Essex.—Gurou. Maa. 1867, Vol.

- p. 63. ;

On the Ferruginous Sands of Buckinghamshire—Gxrot, Mac. 1867, Vol. IV.
p. 456.

Geological Excursion to Bath.—Guou. Maa. 1868, Vol. V. p. 2338.

Notes on the Gravel Beds at Finchley.—Gron. Mac. 1868, Vol. V. p. 411.

On Organic Remains in the Somersetshire Coal-field, 1868, Vol. V. p. 356.

Geological Notes on parts of Northampton- and Lincolnshires.—Gurot. Mac. 1869,
Vol. VI. p. 99.

: On the Genus “chmodus from the Lias of Lyme Regis.—Gzou. Mac. 1869, Vol.
‘I. p. 337.

“Gems and Precious Stones of Great Britian.’’—Popular Science Review, vol. vii.

1868, p. 123, pl. xxiii.
~ «On the Fossil Man at Mentone.’’—Pop. Sci. Rev. vol. xi. p. 283.

*‘ The Cretaceous Flora.”’—Pop. Sci. Rev. vol. xv. pp. 46-59.

The Lead-bearing Districts of the North of England.—Proc. Geol. Assoc. 1869 ;
Grou. Mae. Vol. VI. p. 317.

On the Occurrence of Boring Mollusca in the Oolitic Rocks.—Gxrou. Mae. 1875,
Dec. II. Vol. II. p. 267.

On the Geology of Croydon.—Proc. Mieroscop. Club, Croydon, 1875.

Description of the Fossil Plants, in Professor J. Prestwich’s Memoir ‘‘On the
Geology of the Coalbrook Dale Coal-field.’’—Trans. Geol. Soc. 1840, 2 series, vol. v.

On the Physical Structure of the London Basin.—Proc, Watford Nat. Hist. Soc.
1876, vol. i. p. 89.

The Geology of the District around Aylesbury.—Bucks Archeological Soc.
August, 1862.

The Geology of Hartwell.—Lond. Univ. Mag. June, 1856.

Address to the Geologists’ Association.—Proc. Geol. Assoc. 1877, vol. v. pp. 191-
230.

Geological Diagrams—Reynolds, London, new edition, 1878.

Jomnt PAPERS.

Morris, John, and Thos. Davidson. Descriptions of some Species of Brachiopoda
(Leptena liasina, L. Bouchardi, L. Pearcei, Terebratula rugulosa, T. spinulosa, etc.)
—<Ann. Nat. Hist. xx. 1847, pp. 250-257.

Miss Agnes Crane—Recent and Fossil Cephalopoda. 487

Morris, John, and L. L. Boscawen Ibbetson. Notice of the Geology of the
Neighbourhood of Stamford and Peterborough.—Brit. Assoc. Rep. 1848, pp.
127-181; Roma Corrisp. Scient. I. 1848, p. 33.

Morris, John, and J. Lycett. On Pachyrisma, a Fossil Genus of Lamellibranchiate
Conchifera.—Geol. Soc. Journ. vi. 1849, pp. 399-402.

Morris, John, and John Lycett. A Monograph of the Mollusca from the Great
Oolite, chiefly from Minchinhampton and the Coast of Yorkshire.

Part I. Univalves, 1850, Pal. Soc. Mon. 4to. pp. 130 and 15 plates.
Part II. Bivalves, 1853, op 5 » pp. 148 and 15 plates.

Morris, John, and R. I. Murchison. On the Paleozoic and their associated Rocks
of the Thiringerwald and the Harz.—Geol. Soc. Journ. xi. 1855, pp. 409-450.

Morris, John, and J. Prestwich. On the Wealden Strata exposed by the Tun-
bridge Wells Railway.—Geol. Soc. Journ. ii. 1846, pp. 397-405.

Morris, John, and Geo. E. Roberts. On the Carboniferous Limestone of Oreton
and Farlow, Clee Hills, Shropshire.—Geol. Soe. Journ. xviii. 1862, p. 94-102.

Morris, John, and Daniel Sharpe. Description of eight Species of Brachiopodous
Shells from the Paleozoic Rocks of the Falkland Islands.—Geol. Soc. Journ. ii.
1846, pp. 274-278.

Morris, John, and Thomas Oldham. On the Fossil Flora of the Rajmahal Hills,
Bengal.—Paleontologia Indica, Parts 1-6, 4to.

Morris, John, and Prof. T. Rupert Jones. Geology. First Series. Heads of
Lectures on Geology and Mineralogy, 1866-70. 8vo. pp. 84. London, 1870. Van
Voorst.

Note.—Probably many imperfections will be detected in this list: many Notices
and Reviews, written by Prof. Morris, often replete with original observations, have
appeared in these pages anonymously, or only with the initials “J. M.’’ appended to
them.—Epit. Grou. Mace.

Il.—Tse GeyeraL History or tHe CEpPHALOPpoDA, RECENT AND
Fosstt.!

By Miss Aengs Crane.

Jee of the living forms of Cephalopodous molluscs are now,

thanks to the Brighton Aquarium, familiar to us all; and, as
the habits and characteristics of the squids, octopods, and cuttles
have been duly recorded by Mr. Henry Lee in his amusing book on
“The Octopus,” * published in 1875, I shall here restrict myself to
those points in the structure of the living forms which bear upon
the history of the class as a whole, giving merely those anatomical
details which are absolutely indispensable for a right comprehension
of the nature and affinities of the numerous fossil and extinct members
of the order. I may, however, observe, en passant, that the existence
of a certain sub-stratum of truth in the old stories of giant Cepha-
lopods was ably proved by Mr. Saville Kent, in the “ Popular Science
Review,” for 1874, and that specimens have been more recently cast
ashore in Trinity and Logie Bays, on the coast of Newfoundland, that
may fairly claim to be of enormous dimensions. Thus, in a truly
formidable calamary, or squid, the tentacular arms measured 380 feet,
the largest suckers being one inch in diameter, the shorter (or pedal)
arms were 11 feet long, and the body was 10 feet. Professor Verrill
has also described a huge cuttle, estimating the total length at 40
feet, the large tentacles were 26 feet long, with a maximum circum-

1 This paper, originally read before the Brighton and Sussex Natural History
Society, September 12, 1878, has since been carefully revised and augmented both
by the Authoress and the Editor.

2 « The Octopus.” Henry Lee. London, 1875.

488 Miss Agnes Crane—Recent and Fossil Cephalopoda.

ference of 16 inches at their union to the body. A new genus of
calamary, allied to the Architeuthis of Steenstrup, with arms measur-
ing over 23 feet, was discovered on the island of St. Paul, in the
Indian Ocean, by M. Charles Vélain, the naturalist attached to the
French Expedition for the observation of the transit of Venus, at that
station.’ The size attained by some of the fossil species will be
noted in the sequel.

The Cephalopoda® are more highly organized than any other mem-
bers of the sub-kingdom Mollusca; and, consequently, rank at the
summit of that great natural Fathom of the animal kingdom, com-
prising the invertebrated animals. The technical name of this impor-
tant group of molluscs describes the position of their locomotive and
prehensile organs, which are attached in a circle round the mouth.
The brain, eyes, heart, and lungs, are well developed. The Cephalopods
are all inhabitants of the sea, and are almost universally distributed
in the existing oceans. The geological range of the class is also
great, for they occur, more or less abundantly, i in a fossil state in all
the marine deposits, ranging from the Upper Cambrian formation
upwards throughout the whole sequence of geological strata. They
are divided into two groups, a classification (first proposed by Prof.
Owen)* based on the respiratory system. The more lowly organized
tetrabranchiate, or four-gilled, Cephalopods are characterized by the
possession of a many-chambered external shell, and the absence of
an ink-bag. Our knowledge of the anatomy of this once dominant
class, so abundantly represented in the seas of the Palzeozoic and
Secondary periods, is founded solely on the structure of the Pearly
Nautilus, the only member of the order surviving in the existing
oceans. Dead shells of this genus, of which there are at most three
species, are a common object in our museums, but the animal in-
habiting that wondrous dwelling has but rarely been obtained. It
was, however, certainly known to Aristotle, but no further observa-
tions were recorded until those of the Dutch naturalist Rumphius
in 1705. It long headed the list of rarities desired by Cuvier, but
that illustrious naturalist unfortunately died three days before the
publication, in 1882, of Professor Owen’s elaborate memoir * based
on the study of a specimen, caught by his former pupil, Dr. Bennett,
when drifting on the surface of the South Pacific Ocean, off one of
the New Hebrides Islands. <A living specimen was also dredged
in 800 fathoms during the cruise of the “Challenger,” near the
Windward Islands.2 The shell of the Nautilus is divided by shelly
partitions or septa into many cells or chambers, which are connected
by a siphuncle, or tube, centrally situated. The animal inhabits the
last and most spacious chamber, and has the power of forming a
fresh one when necessary. Hach chamber was thus occupied in

1 Remarques au sujet de la faune des Tles Saint Paul et Amsterdam, etc. Charles
Vélain, Paris, 1878. 8vo.

2 « Head-footed Mollusca,”’ from repadt ‘head’ and mois ‘ foot.’

3 See also Baron Cuvier’s Anatomie des Mollusques for details of the structure
of the Dibranchiata.

4 On the Pearly Nautilus. Richard Owen. London, 1832. 4to.
® Proceedings Royal Society, 1874. i

Miss Agnes Crane—Recent and Fossil Cephalopoda. 489

succession. The functions of the siphuncle have been variously
interpreted. First by Dr. Hooke, in 1696, as serving to admit water
to the aerial chambers when the animal was desirous of sinking to the
bottom of the sea. The difficulty attendant on the expulsion of the
water, and the re-admission of air in the ocean depths, was solved by
supposing the Nautilus to be gifted with the power of secreting an
aerial fluid at will. But, the fact that the siphuncle only pierces the
septa, and has no connexion with the aerial chambers, renders this
theory unacceptable. Dr. Buckland' held that the siphuncle com-
municated with the pericardium, and received a fluid contained
therein when the creature was desirous of altering the specific
gravity of the shell in order to sink beneath the waves. According
to Prof. Keferstein,? of Géttingen, the Nautilus periodically secretes
an aerial gas from the base of its mantle, which is prevented from
communicating with the sea water by a special structure, and the
gas thus generated causes the animal to move upwards in its shell,
and supports its weight when the construction of a new chamber is
necessary, the shell muscles advancing gradually and not being
abruptly ruptured as supposed by D’Orbigny. The air thus secreted
is then inclosed by a nacreous deposit from the mantle, and a new
aerial chamber is completed. M. Barrande, who has treated the
subject of the functions of the siphuncle, and the progression of the
mollusc in the water, in a most impartial and exhaustive manner,
in his magnificent memoirs on the Paleozoic Cephalopoda,’ considers
the enforced periodic rests, imposed on the creature by Prof. Keferstein
immediately after the formation of a new chamber, to be irreconcil-
able with the free liberty of movement enjoyed by the other members
of the cephalopodous class, and obviates this necessity by assuming
that the surface of the mantle endowed with the power of exhaling
the aerial gas is also capable of re-absorbing it, and thus the ascent
and descent of the Nautilus in the water is entirely under the control
of the will of the animal.

Some authors, however, maintain that the movement of the animal
in or out of the shell was sufficient to facilitate its progression in
the water, and regard the siphuncle as serving either to attach the
animal to its protective covering, or to insure the repair and vitality
of the whole of the shell, and a few, as destined merely for the
reception and development of the eggs. Others believe that the
Nautili live habitually at the bottom of the sea, being only driven to
the surface during storms, or when in a dying condition; an argument
that is supported by the fact that their chief food appears to consist
of the hairy non-swimming brachyurous crabs which live always on
the ocean floor. Among those holding this view, and therefore
recognizing no necessity for the ingenious theories of Professor
Keferstein, and M. Barrande, Dr. Henry Woodward deserves especial

1 Bridgewater Treatise. Geology. 1836.

2 Bronn’s Klassen u. Ordnungen d. Thierreich, III., Malacozoa, 2te Abtheil:,
p- 1844.

3 Systéme Silurien de la Bohéme, vol. ii. texte, v. pp. 962 and 1235. Joachim
Barrande. ‘ Prague, 1877. :

490 Miss Agnes Crane—Recent and Fossil Cephalopoda.

mention! for the lucidity with which he has expressed his opinions
in an interesting paper “On the Structure of Camerated Shells,”
published in the Popular Science Review in 1872.2 He there con-
tends that the Nautili do not swim, but are sluggish crawling
animals, and bottom-feeders, and consequently do not require buoyant
shells furnished with air-cells, if indeed the so-called aerial chambers
could act as such, liable as they would be to become partially filled
with sea-water, which must undoubtedly penetrate by endosmosis
through the pores. He denies the possibility of the siphuncle main-
taining the vitality of the shell, because it is certainly a non-vascular
structure, and there is no connexion between it and those portions of
the shell which lie in contact with the mantle, the sole shell-secreting
organ in the Mollusca. The divisional septa are regarded as indica-
tions of periodical, natural, and reproductive growth,’ and as possibly
serving “to shut off the discarded and untenantable” parts of the
shell; and he regards the siphuncle as the remnant of a rudimen-
tary or embryonic organ, which attached the animal to the shell in
its earliest stages, a function that would well accord with the ex-
istence of enormous siphuncles in some of the most ancient fossil
forms when the embryonic conditions were probably retained during
life. A somewhat similar camerated, or chambered, structure exists
in many Gasteropods (Helix, Huomphalus, etc.), and also in aged
oysters and other bivalves, while in some corals a central tube is
visible with radiating septa or partitions. Dr. Woodward therefore
does not admit the organization of the chambered shells of the
Cephalopoda to be an entirely exclusive structure, but considers it
as only a modification of the shell-structure found in other mollusca.

The parrot-like jaws of the recent Nautilus are blunt and calcareous
at their tips, and similar beaks, called Rhyncholites, formerly regarded
as those of fossil birds, occur in all strata associated with the fossil

Tetrabranchs, and are now referred to extinct species. “The digita-.
tions, or lateral processes,” thirty-eight in number, are retractible
into eight sheaths, corresponding to the eight ordinary arms of the
cuttles. The two dorsal arms unite to form the hood which serves
to close the opening at the mouth of the shell. All these numerous
arms are unprovided with suckers. There are four gills or branchiz,

1 My attention has been called by Dr. H. Woodward to a valuable contribution
to this subject by Professor H. Govier Seeley, F.G.S., in the report of the British
Association for the Advancement of Science, 1864, Bath, Transactions of Sections,
p- 100, entitled “On the Significance of the Septa and Siphuncles of Cephalopod
Shells;”’ see also the Quart. Journal of Science, October, 1864.

2 British Association Reports, Liverpool, 1870, Transactions of Sections. Popular
Science Review, 1872. See also Note at the end of the present article, p. 499.

3 On my recently calling the attention of Prof. James Hall, LL.D., to these views
as to the significance of the septa in the chambered Cephalopods, that distinguished
American paleontologist, whilst fully admitting the force of the hypothesis of their
production by those natural causes, suggested that the fact of the septa being com-
posed of three distinct layers of shell-substance, viz. an outer nacreous one, an inner
porcellanous one, and a third external nacreous deposit, could hardly thus be ac-
counted for. As both the external surfaces were smoothed and polished, apparently
by the application of some part of the body of the animal, it was further difficult

to conceive how access was obtained to the outer surface of the last formed septa
after the animal had once partitioned off its body in the manner supposed.

Miss Agnes Crane—Recent and Fossil Cephalopoda. 491

and the circulatory and respiratory apparatus is less highly developed
than in the succeeding dibranchiate forms. The digestive system
is, however, similar, consisting of a crop and a gizzard, resembling
that of the common fowl. The curious fossil plates called Aptychi,
now known as the opercula, or defensive covering to the aperture of
the body-chamber of the shell, of the extinct family of Ammonites,
were at one time considered to be the fossil gizzards of Cephalopods.
They were also described as bivalve shells, but the discovery of an
Ammonite in which they were revealed in situ, filling up the opening
of the shell, sufficiently indicated their true nature.' The Nautilus
carries its shell snail-fashion when crawling, by means of its many
feet, head-downwards, at the bottom of the sea. The specimen kept
alive for a few hours on board the Challenger, propelled itself back-
wards and forwards by the expulsion of water from the funnel, after
the fashion of the Octopods.

The Nautilus is the sole “persistent type” among all the varied
forms of the Cephalopods, that is to say, it forms the only genus
which has been represented in all geological ages since the deposi-
tion of the primeval Silurian rocks. The genus underwent some
strange vicissitudes. One of the twelve primitive cephalopodous
types, it was represented by twelve species in the Lower Silurian
seas, these decreased to ten in the succeeding Upper Silurian epoch,
and to eight in the overlying Devonian. No less than eighty-four
species swarmed in the Carboniferous seas, evidently most favour-
able to their development. Of these, all save five were extinguished
during the deposition of the Permian rocks, a period of the world’s
history when life was, comparatively speaking, not so abundant in
the waters of the earth; or when perhaps (speaking more correctly)
the sedimentary deposits were less favourable to the preservation of
the organisms entombed within their now highly-altered strata.
Forty-seven species re-appeared in the Triassic and Jurassic forma-
tions, while during the Cretaceous epoch the Nautili attained their
second maximum point of development, 63 species being recorded
from those deposits. These again declined to 15 in the Tertiaries,
and to three? in the existing oceans.* Truly of most ancient lineage,
a contemporary of some of the earliest forms of life, the Nautilus
has been a witness of many successive changes in the physical
features of the world, and surviving the unknown causes so fatal to
all the other members of its race at the close of the Cretaceous
period, has held its own in the battle of life, and now forms one of
the most curious and interesting of the living wonders of the deep.

Twenty-five genera of fossil Tetrabranchiates were represented in
the Paleozoic seas. Twelve of these were primitive cosmopolitan
types, and occur in beds at the base of the Lower Silurian formation

1 See paper by Dr. S. P. Woodward on an Ammonite from the Inferior Oolite

with the operculum in situ, ‘‘ Geologist,” vol. iii. 1860, p. 328.
_ ® As the broad-mouthed Nautilus pompilius is the female, it is highly probable
that the V. umbilicatus is the male of the same species. Among Ammonites both
tumid and flattened forms have been observed in most species. See ‘‘ Woodward’s
Manual of the Mollusca,” p. 83.

3 Céphalopodes, Etudes Générales. J. Barrande. 1877. Table 1, p. 84.

492 Miss Agnes Crane—Recent and Fossil Cephalopoda.

in all parts of the world. These primitive types are, however, widely
divergent, comprising the Nautilus, the curved Cyrtoceras, the straight-
shelled Orthoceras and Endoceras, the club-shaped Gomphoceras, and
the simply-coiled Lituites. Some of these generic forms enjoyed a
very brief existence, and after becoming specifically numerous, died
out almost as suddenly as they appeared. The Orthoceratites were
certainly, among the mollusca, the giant rulers of those ancient seas,
and many attained large dimensions, measuring ten or twelve feet
in length. One American species, truly an Orthoceras Titan,’ esti-
mated by Dr. J. 8S. Newberry as weighing ‘‘ some tons,” must have
fairly rivalled the fabled living “Kraken,” endowed by the older
naturalists with the power of sinking a ship seized in the clutches
of their snake-like arms. The shell of Orthoceras is straight, and the
septa of the vertical chambers, pierced by a nearly central siphuncle,
are simple at their edges, like those of Nautilus. The last chamber
seems comparatively small for the occupation of an animal capable
of sustaining and directing such an enormous shell, and it has been
suggested that the shell was internal as in the living cuttles and the
extinct Belemnites. This view, which is not generally entertained,
was considered by the late Dr. 8. P. Woodward? to be untenable on
the grounds that in some specimens the exterior colour-bands appear
to have been preserved on the outer surface of the shell, and thus
prove it to have occupied an external position. There were 260°
species of Orthoceras in the Lower Silurian rocks, a number which
increased to 626 in the Upper Silurian seas, when the life-conditions
were very suitable. They declined rapidly in the succeeding Palzo-
zoic epochs, and were represented only by fourteen dwarfed forms
in the Triassic deposits, the dawn of the great Secondary life-period
of geologic history. In the curved and elegant Cyrtoceras, the
increase from 90 specific forms in the Lower Silurian rocks to 299 in
the upper beds is even still more remarkable, and affords an idea of
the enormous duration of time that must have elapsed during the
deposition of that early fossiliferous series. Only one species of the
genus survived in the Permian era.

In the coiled Goniatites of the Upper Silurian beds we have the
first indications of that ornamentation of the edges of the chambers,
which subsequently became such a marked and beautiful feature in
the numerous family of the Ammonites which ranged in Kurope from
the Trias to the Chalk, and of which there are several hundred
known species. Some specimens found in the Carboniferous rocks
of India must have been contemporary with the Goniatites, a fact
that is not without interest when the theory of the evolution of the
class comes to be considered. Ammonites have also been obtained
from the Oolitic deposits in the passes of the Himalayas at a height
of over 16,000 feet above the level of the sea, and afford a striking
instance of variations in the physical configuration of the world, for
it is obvious that when they lived and died the Himalayas were not,
and similar paleontological data prove that those snow-clad moun-

1 State Reports of the Geology of Ohio.—Palzontology, vol. i. p. 263.

2.Manual of the Mollusca. 2nd edition, 1868. S. P. Woodward.
3 Barrande, ibid.

Miss Agnes Crane—Recent and Fossil Cephalopoda. 493

tain peaks were not upheaved until a comparatively recent period.
The body-chamber of the Ammonite seemed to be so small in pro-
portion to that of the Nautilus that Dr. Gray’ was led to conclude
that the shell was not inhabited by the animal, but was internal, re-
sembling that of the existing Spirula. The fact is, the last chamber
is rarely preserved in an unbroken condition, there being, of course,
no septa to strengthen the walls of this last part of the shell, which is
in consequence usually crushed and flattened. But occasionally the
interior, discoloured by the decomposition of animal matter, furnishes
indisputable evidence that the creature inhabited it during life, and
was buried in it after death.? The siphuncle is next the keel, and the
edges of the septa, where they unite with the shell-wall, are beauti-
fully foliated in various patterns peculiar to the respective groups.
This foliation is very remarkable in some species, and is visible in
all when the outer surface of the shell is removed. As in all these
fossil genera, the classification of the Ammonitide is necessarily based
on the characters of the shell alone. There are sixteen type-groups,
each of which characterizes a certain horizon, and the presence
of a member of a group in any deposit denotes its position
in the geological series. In the Liassic formation even species of
Ammonites are said to be restricted to a certain horizon, and never
to occur out of it;* a knowledge of the limits of these groups is
therefore of great service to the seekers for any of the rich
industrial products for which that formation is so noted. Thus,
although the rich ironstone bands occur only in the zone of Ammonites
spinatus, many useless searches for iron were formerly made in the
beds characterized by Ammonites annulatus, the outward appearances
of the strata being identical. Again, the familiar Ammonites com-
munis is found only in the alum shale, and Ammonites serpentinus in
the jet-bearing rocks. The numerous representatives of this most
extensive genus were originally grouped in sections or families, a
very artificial mode of division. The far more consistent method,
first inaugurated by Continental palzontologists, of assigning generic
names to the various series of characteristic species, is now, however,
becoming generally adopted in England. The interesting family of
the Ammonitide reached its maximum in the Jurassic epoch; it was,
however, numerously represented in the Cretaceous seas, and some
specimens attained large size, measuring over three feet in diameter.
On their total extinction at the close of the Chalk period, they can by
no means be regarded as an effete race, for several varied types, such
as Turrilites, Scaphites, and Hamites, etc., made their appearance in
the Cretaceous epoch, but, enjoying a very restricted range, died out

1 Post-Hocene Period.

2 Ann. and Mag. Natural History, 1845, vol. xv. pp. 247 and 444.

3 Specimens of A. heterophyllus and of A. perarmatus, and many other species,
preserved in the British Museum, show the body-chamber to have been of very large
extent.—H. W.

4 This conclusion, however, so contrary to all known zoological laws regulating
the distribution of life in time and space, may well be received with great caution,
even when given on high authority and apparently borne out by many and wide-
spread facts—H. W. .

494 Miss Agnes Crane—Recent and Fossil Cephalopoda.

almost as suddenly as some of the more ancient members of that
tetrabranchiate group, of which they were nearly the last representa-
tives. .

In the more highly organized, but, geologically speaking, modern
class of dibranchiate, or two-gilled Cephalopods, the shell is internal,
and rudimentary in the Octopoda, either horny as in the squids, or
calcareous and laminated as in the cuttles. In these ‘‘naked” forms,
respiration is effected by means of two gills instead of four. The
dibranchs are active free-swimming animals possessing super-added
branchial hearts, and, therefore, a more complex and vigorous
circulatory system, which gives them increased powers of locomotion.
The ink-bag is always present more or less developed, and its
preservation in a fossil state is regarded by Professor Owen as certain
evidence of the existence of forms unprotected by an external
defensive shell. The parrot-like mandibles are horny, and are quite
hidden from view at the base of the web uniting the arms to the
body. In the Octopoda, or eight-armed species, it is important to
remember, they form the only portions of the animal susceptible of
preservation in sedimentary strata. In the cuttles, the two long
additional tentacular arms are retractible, and are only extended
when the animal is capturing its living prey, or in the act of dissolu-
tion. In some species of the Calamaries or squids, they are rendered
still more formidable weapons of offence and defence by the addition
of a double series of horny hooks attached to the club-like ends of
the tentacles. In the anomalous genus Argonaut, or Paper Nautilus,
the Nautilus primus of Aristotle, the position of the one-celled shell
is external.! It is, however, believed to be peculiar to the female,
and, not being attached to the animal by shell-muscles, is considered
as serving more probably for the protection and incubation of the
eggs. Two species of this genus occur, fossil, in later Tertiary
deposits. In Spirula, again, the shell, though internal, is many-
chambered and siphunculated. Dead shells of this genus abound in
the warmer seas, but the animal has been but rarely obtained,
except in a more or less fragmentary condition. Specimens were
fortunately procured during the cruise of the “ Challenger,” and will
receive a detailed description from Professor Huxley. Spiru/a is an
exceptional form that may possibly be found to possess characters
uniting the dibranchiates to their more lowly organized predecessors,
and will, at any rate, throw additional light on the structure of the
fossil members of the order to which, from the presence of an ink-
bag, it was originally referred by Professor Owen.’

Of the existence of this highly-organized class of Cephalopods
prior to the Secondary period, we have purely negative evidence.
If any of their forms inhabited the Paleozoic seas, they have lett no
certain traces for the instruction of the naturalist. The earliest

1 This must be understood in a modified sense. The fact is the two broadly-
expanded (shell-secreting ?) dorsal arms (figured as “sails” in the allegorical
representations of the “‘ Argonaut’’) closely envelope the shell on either side, so that
in the lifetime of the animal the shell is almost, if not wholly, concealed; whereas

the animal can but partially conceal itself within the shell—H. W.
2 Voyage of H.M.S. Samarang (Zoology), pp. 6-17, pl. 4, 4to. 1848,

Miss Agnes Crane—Recent and Fossil Cephalopoda. 495

known appearance of the group is in the Trias, when the extinct
family of Belemnites, which subsequently became such a marked
feature in the Jurassic seas, was first represented by a few forms
which were the contemporaries of the last surviving members of the
once powerful race of Orthocerata. These apparently primitive
Belemnites lived in the shallow seas in which were deposited the
St. Cassian beds of geologists (situated in the Austrian Alps), so
famous for the admixture of Paleozoic and Secondary types, and
as serving to indicate the absolute continuity of the geological
series. Of the now numerous family of Octopods, we have no
trace in a fossil state, although, as already stated, their horny
mandibles are susceptible of preservation. Beaks, of a similar
horny texture, occur in rocks of Secondary and Tertiary age; but
their size and shape is suggestive of their belonging either to the
fossil cuttles and squids, or to their extinct allies, the Belemnitide,
whose remains are associated with them in the same strata. The
inference that giant naked Cephalopods existed in the Palzeozoic seas
with calcareous jaws, is, of course, a purely speculative one. The
distribution of the true cuttles (the Sepiade) is universal in the
existing oceans. Remains of the family are preserved in the Lias
Oxford clay, other Oolitic deposits, and in the Tertiaries. The
living Teuthide, the Calamaries, or squids, are also widely dis-
tributed. They are found fossil in the Upper Liassic, Oolitic,
Cretaceous, and Tertiary formations.

The history of the organization of the fossils comprising the
remaining dibranchiate family, the now wholly extinct Belemuitide,
was long involved in mystery. Specimens of the remarkable genus,
Belemnoteuthis, were preserved in a marvellously perfect manner
in the Oxford clay, at Chippenham, in Wiltshire, the mantle,
fins, eye sockets, beaks, and tentacles being all entombed in juxta-
position. The internal, vertically chambered, partly calcareous
skeleton, is attached to a horny pointed guard, resembling the
familiar “thunder-bolt ” of our childhood. The animal was indeed
first described by Professor Owen,' in 1844, as that of the true
Belemnite ; but it is now considered as being more allied to the
Calamaries, especially to the genus Onychoteuthis, now existing in
the Indian Ocean, the tentacles in both forms being armed with a
double series of formidable horny hooks. Dr. Mantell? first showed
that this curious fossil possessed some points of internal structure
that could not have been associated with, or fitted into, the horny
guards forming the apex of the chambered skeleton of the Belemnite,
and the affinities of Belemnoteuthis were then recognized as being
with the Calamaries; but Professor Owen still maintains that it
illustrates the close connexion existing between the two groups of
organisms. Indeed, the Belemnitide may be fairly regarded merely
as an extinct branch of the Squid family. The presence of an
ink-bag and ten arms in the animal to which the appendage known
as the Belemnite belonged, was first suspected by Dr. Buckland ;?

1 Phil. Trans., 1844. On the animal of Belemnite. :
2 Phil. Trans., 1848 and 1850. 3 Bridgewater Treatise, 1836.

496 Miss Agnes Crane—Recent and Fossil Cephalopoda.

but, it was not until the description by Professor Huxley‘ of an
interesting fossil from the Ammonites obtusus zone of the Lower
Lias, near Charmouth, in Dorset, in which the parts of the internal
structure known respectively as the pointed guard, the phragmocone,
or chambered portion, and the nacreous pro-ostracum were found
in siti, with indications of an ink-bag, and tentacles armed with
horny hooks one-sixth of an inch long, that the anatomical details of
the genus Belemnites, as distinct from that of Belemnoteuthis, were
at length finally and satisfactorily established.

So far, it is obvious, that there are two distinct types of Cephalo-
pods. One, with an external chambered shell, simply constructed
eyes, four gills, no suckers, and no ink-bag, very abundantly repre-
sented in the ancient seas, and those of the middle geologic epoch,
and of which one genus only survives at the present day. The
other, possessing an internal shell, two gills, tentacles armed with
suckers, and sometimes hooks, an ink-bag, and perfect organs of
vision, appeared first in the Triassic period, was largely developed
in the Jurassic seas, and predominates in the existing oceans.
When the ancient tetrabranchs were the rulers of the seas during
the “reign of Molluscs,” the Gasteropodous class was represented
chiefly by the lowest organized herbivorous forms, the carnivorous
snails, etc., not making their appearance until the Secondary epoch,
when they became the contemporaries of the dibranchiate Cephalo-
pods. In past ages the Tetrabranchs probably performed the office
of restricting the undue increase of the co-existing Crustaceans and
Mollusca, and possibly their own numerical abundance was in turn
influenced by the appearance and development in Devonian and
Carboniferous times of the formidable armour-plated fishes. In the
Secondary period, the dibranchiates served as food for the extinct
Hnaliosaurians, or Sea-lizards, as in the present day, for the pre-—
dacious fishes, penguins, and other sea-birds, some species of cetacea,
and, in a few countries, even for man.” Thus, both groups fulfilled
their functions in the economy of nature, and the balance of power
was maintained. Of all the vast families of Nautilide, Goniatide,
and Ammonitide, the long-lived Nautilus alone survives. Whether
the increase of the more highly organized group affected the further
development of the lower forms, cannot positively be affirmed; but
it is certain that the causes which led to the extinction of the
Tetrabranchiates (with the exception aforesaid), at the close of the
Cretaceous epoch, had no influence whatever upon the more highly
organized forms, which persisted through the Tertiaries, and abound
in the existing oceans.

There remains but to consider the evidence of the Cephalopods
with regard to the theory of Evolution, a subject on which opinions
are naturally very diverse. The existence of a certain amount of

1 Mem. Geological Survey, Monograph IT., 1864. tana

2 Octopods, cuttles, and squids were highly esteemed as epicurean dainties in
ancient Rome, and the former are now largely consumed as food in the sea-coast
towns of France and Italy. While according to Dr. Macdonald the Pearly Nautilus
is regarded as an agreeable viand by the inhabitants of the Feejee Islands! :

Miss Agnes Crane—Recent and Fossil Cephalopoda. 497

progressive development in the history of the class, so far as relates
to the first appearance of the lowest forms in the primeval oceans,
and to the succession of that more highly developed group, which
mainly represents the order at the present day, cannot reasonably
be denied. The occurrence of certain comprehensive types, uniting
characters which subsequently became distinctive peculiarities of
diverse genera, must also be admitted. Thus, as Professor Owen?
has shown, in the Belemnitide are united the internal chambered
and siphunculated structure retained solely in the existing Spirula,
while the horny armature of the tentacles is at present restricted to
one genus of the living Calamaries, but he does not fail to point
out that the perfect preservation of the fossil forms has revealed the
fact that the armature of the Secondary Cephalopods was as highly
organised as that of any of the species inhabiting our present seas,
and is not, therefore, indicative of any great rate of progression, not-
withstanding the enormous intervals of time that must have elapsed
between the Secondary and the Recent period. Again, according to
Sir Charles Lyell,? «The rate of progression has been slow indeed, if
the only step realized between the Lower Silurian and modern times
can be expressed by the passage from the tetrabranchiate to the di-
branchiate Cephalopod, a rate of progress that might require a course
of ages anterior to the Silurian epoch, as great as that which has since
elapsed in order to bring about a gradual evolution from a Bryozoon
to an Orthoceras.” The important testimony of M. Joachim Bar-
rande,’ founded on a special and extended survey of more than 2,00
Palzeozoic species, is also directly opposed to the theory that one form
has been evolved from another. That illustrious paleeontologist, who,
from his vast labours among the Paleozoic rocks of Central Germany,
may be fitly entitled the “Murchison of Bohemia,” contends that
the recent Nautilus possesses the same essential characters as the
earliest known forms so universally distributed at the base of the
Lower Silurian formation,’ that a detailed examination of the struc-
ture of the Tetrabranchiate Cephalopods, whether as applied to the
position and diameter of the syphon, the size, composition and
ornamentative characters of the shell, furnishes no evidence in
support of the theories of descent by modification, natural selection,
or the survival of the fittest; and further, that the stability of
generic types, and the distribution of the group in geological time,
is equally opposed to them. The complex forms, moreover, often
precede the simpler ones, while those which appear to be inter-
mediate follow the genera which they might otherwise be supposed
to connect. It must, however, be noted that the arguments as to
the relative simplicity, or complexity, of structure, are founded

1 Phil. Trans., 1844.

2 Principles of Geology, vol. i. p. 150, ed. 1872.

3 Etudes Générales, etc., Barrande.

4 It must always be borne in mind, when arguing from these early fossil molluscan
remains, that we have only the shells preserved to us. We know nothing of the
animals. Our argument then is founded on assumption, and must be treated ac-
cordingly. See “ Distribution of the Cephalopoda in Silurian Countries,” by
J. Barrande. Reviewed in Grou. Maa. 1870, Vol. VII. p. 490.

DECADE II,— VOL. V.—NO. XI. 32

498 Miss Agnes Crane—Recent and Fossil Cephalopoda.

solely on an investigation of the characters of the external shell,
a test that is by no means a sure indication of corresponding differ-
ences in grades of organization of the animals inhabiting them, and
therefore the classification of zoologists is rightly based on those
internal characters which affect the life-conditions and habits of the
animal, — characters of which we are necessarily often entirely
ignorant in the case of fossils derived from the Paleozoic rocks.
Again, with regard to the distribution in time, we are confronted
with the fact that of the whole 25 Paleozoic genera, no less than 12
varied types, or nearly one-half of the whole, occur simultaneously
in all parts of the world at the same geological epoch. ‘This wide
distribution of the so-termed primitive types is, however, capable of
being interpreted by Evolutionists as proof of their antiquity ; and
they will probably define the conclusion that they are the first repre-
sentatives of the group, as an unsound one, based, as it undoubtedly
is, on purely negative evidence, and reply that their predecessors —
have yet to be discovered in some of the unexplored Cambrian areas.
But M. Barrande’s most valid objection to the theory ‘of the evolu-
tion of the class, one with which I am not competent to deal, is
assuredly that founded on a critical investigation of the embryonic
characters of the Ammonitide and Goniatide, as compared with that
of the Nautilide. 'These researches lead him to the conviction that
important embryological distinctions exist between the development
of the Ammonites and Goniatites, and that of the Nautilide, which
preclude the reception of the idea that the Secondary Ammonitide
were derived from the Goniatites, and they, in their turn, from the
primitive Nautili. To quote from the able and most instructive
anniversary address of the late President of the Geological Society,’
Professor Martin Duncan, F.R.S., “The examination of the earliest
formed portion of the shell of Nautilus and Goniatites indicates
embryological distinctions, and, therefore, it is necessary to seek in
the remoter Palzozoic Nautilide for the ancestors of Nautilus and
Goniatites.”

One further point deserves notice, namely, the occurrence at
various geological horizons of distinct generic forms, which repre-
sented by a few, or possibly by several species, nevertheless die out
at the close of that short geological period, and never re-appear.

“ So careful of the type P’’ but no,

From scarped cliff and quarried stone

She cries, “‘ A thousand types are gone,

I care for nothing, all shall go.”

Tennyson’s In Memoriam.

This fact, which is observable in many other groups of organisms,
notably in that of the Brachiopoda, as was so clearly explained by
Mr. Davidson ? in his admirable memoir, is explicable only, either by
the hypothesis of descent with modification, or by that of the
doctrine of special creation. In this instance it would perhaps

1 Quarterly Journal Geological Society, London, May Ist, 1878, p. 69.

2 What is a Brachiopod? Brighton and Sussex Natural History Society. Feb.
11th, 1875; Guotocican Macazing, April, May, June, 1878; Annales de la Société
Malacologique de Belgique, 1876.

Miss Agnes Orane—Recent and Fossil Cephalopoda 499

seem a more exalted conception to infer that, in these abandoned
types, we have the modified descendants of a few remotely antecedent
created types, than to maintain that, in common with the numberless
specific varieties, they were each individually created at successive
and constantly recurrent periods,—for the fact that they made their
appearance on the earth at very different epochs of geological time,
is as indisputably proved as that of the orderly and successive pro-
gression from the Crustaceans and Molluscs to the Fishes, Reptiles,
and Mammals. But I will not enter further upon the speculative con-
troversies as to the origin of the Cephalopoda. Scientific doubts and
perplexities, like all other intellectual difficulties, should be solved by
individual thought, the result in most cases being dependent on the
peculiar bias of the observer. In this necessarily imperfect sketch
of the annals of the Cephalopods, I have merely endeavoured to
place the evidence impartially before you. I wish, however, to be
understood as clearly distinguishing between what may be termed
“ Rational Evolution,” a phase of the doctrine based on legitimate
deductions from well-ascertained facts, as widely separated alike
from “Advanced Darwinism” and dogmatic Materialism. The
investigation of the past history of any group of organisms
inevitably trenches on the theories of Evolution; for, in the words
of one of the most popular exponents of paleeontological science,
Dr. Alleyne Nicholson,’ “it is to that science, perhaps more than
any other, that we may look for the key to some most interesting and
important theoretical problems in biology.”

Note.—The writer regrets that she has only now had her atten-
tention called to a most interesting paper by Prof. Owen, entitled
“Observations upon the Camerated Structure in the Valves of the
Water-clam (Spondylus varius, Sow.),” which was originally printed
in the Proceedings of the Zoological Society for June, 1837, and
afterwards in the Magazine of Natural History, vol. ii. 1838, p. 407,
in which the author traces out the connexion between the mode of
growth in Nautilus and that of other molluscs which partition off a
portion of their shell not required for the convenience of the soft
parts of the animal inhabiting it. Although in this paper Professor
Owen speaks of the siphon of Nautilus as a means for converting the
deserted chambers of the shell into “a hydrostatic instrument sub-
servient to the locomotion of the animal,” yet he clearly points out
that the septal divisions of the Nautilus-shell are analogous to the
septa of the “water spondylus” and many other shells which
partition off the dis-used portion of their houses both among uni-
valves and bivalves.

Dr. Henry Woodward, F.R.S., to whom Professor Owen showed
this paper a few days since, was, he informs me, until then, wholly
unaware of its publication, and only regrets that he did not discover -
it when writing upon the subject of Camerated Shells, so as to have
given Professor Owen due credit for these views published so long
before his own.—A. CO.

-1 Recent Progress in Paleontology, GzoLocicat Macazine, January, 1878; the
Inaugural Address to the Edinburgh Geological Society, November, 1877.

500 J. W. Davis—The Valley of the Calder.

IJI].—Tut Puystcat Forcrs wHicH HavVE CAUSED THE PRESENT
CoNFIGURATION OF THRE VALLEY OF THE CALDER IN YORKSHIRE.!
By James W. Davis, F.L.S., F.G.S.,
Hon. Secretary of the Yorkshire Geological and Polytechnic Society.

Y way of introduction to the subject of this paper, I will very
briefly describe the physical features of the country drained by
the River Calder. We shall thereby gain a clear idea of the present
configuration of the Calder valley and better understand how the
forces have operated which have produced the grand diversity of hill
and valley, of moorlands bleak and wild, of precipitous crag, and
steep, wooded slopes, and of the lower lands, rich and fertile, which
extend along their base. To know clearly what has been done, is
more than half to understand how it has been done.

The River Calder is, roughly speaking, about forty miles in
length, and drains about 400 square miles of land. It has its source
in several small streams which rise far up in hills around Tod-
morden. The principal feeder has its origin in Lancashire, and
passes through a break in the chain of hills separating that county
from our own. Pursuing an easterly course, the united streamlets
wend their way from Todmorden to Hebden Bridge, and are there
joimed by a large tributary from the Wadsworth and Widdop
moors. It is the stream from the latter that is intercepted and
collected into large reservoirs by the corporation of Halifax. The
water is conducted thence in a large conduit, which passes at a
depth of 500 feet or more, under Wadsworth moor, and so on to
Halifax. A short distance below Hebden Bridge is another very
pretty village called Cragg, and passing through this is a small
river which descends from the moorlands of Langfield. No doubt
many of my readers have been either to Hebden Bridge or in
Crage valley, and will have a vivid recollection of those really
delightful places. They will remember the precipices of sandstone,
which rise from the level of the bed of the stream, in some
instances, as at Hebden Bridge; succeeded by gentler slopes, which
are either covered with trees or grassland. Originally they were all
wooded, the trees having been cut down during late years by the
farmers and others, who thought they could make some profit out of
the land if they could use it for grazing cattle or growing corn,
whilst if the trees remained they would probably not be able to
do so. The result of this utilitarianism has been to render many
parts of the valley far less pretty than they would have been had
the trees been left standing.

The grassland generally extends high up the hills, to the verge of
the moorland, which everywhere covers the tops of the hills, stretching
away mile after mile, in long monotonous undulations; occasionally a
stream cuts deep into the surface, otherwise there is little to break
the sameness which exists on all sides. The moors are covered with
furze and heather, with occasional small patches of short green
grass. They are wholly given up to grouse and a few sheep. The

! Read at the Orphanage, Halifax.

J. W. Davis—Tne Valley of the Calder. 501

decay of the heather produces peat, and this in most places has a
thickness of from six or eight to twelve feet; below that again is
sandstone. You may always be sure that, wherever heather and
peat occur, the rock below the surface is sandstone. You will never
find the heather growing on a bed of limestone, or shale, or clay,
but always on sandstone.

Leaving these elevated moorlands for a time, let us follow the
course of the river from Mytholm to Sowerby Bridge. It passes
amongst steep declivities of shale or more precipitous ‘edges ” of
gritstone; generally the shale slopes up to the foot of the grit, the
latter projecting in angular cornices above it. This is the character
of the scenery, not only of Calder valley, but also of the tributaries
which join it from the Ripponden and Luddenden valleys, and those
from Halifax on the one side, and Barkisland and Stainland on the
other. Below Elland, the valley, which has been hitherto very
narrow, assumes greater proportions, its surface being arranged in a
series of long level flats through which the river has cut its channel
with many devious turnings and windings. The valley is bounded
on either side by hills, which rise to a considerable height, but are
characterized by a more rounded outline than those nearer the source
of the river. The escarpments of sandstone are wanting, and though
the general character of the two areas is somewhat similar, there is
still sufficient difference to indicate to an experienced eye that they
are not of the same geological composition. Such is, in fact, the
case; the river in its initial stages runs amongst hills of Millstone-
grit, whilst from Elland, downwards, its course is amongst the Coal-
measures. ‘The former are characterized by thick beds of sandstone,
which form the steep escarpments already described; whilst the
latter, composed more largely of shale with beds of coal, form
rounded summits only, now and then capped by a bed of flagstone.

The country becomes flatter until Wakefield is arrived at, after
which the hills gradually disappear; and, with many convolutions,
often turning quite round, and running a short distance backwards,
the river reaches Castleford and empties itself into the Aire. The
district about Lofthouse, Methley and Normanton is comparatively
flat and tame. It is composed of the Middle Coal-measures, and
forms a rich agricultural district. Its greatest value is, however,
not on the surface, but in the mineral wealth, which lies buried
hundreds of feet below. The Coal-pits, which are numerous, do not
tend to improve the appearance of the country.

The geological structure of the country drained by the Calder
next demands consideration. ‘The whole of the rocks in this area
constitute a part of what is called the Carboniferous system, so
named from the occurrence of great quantities of coal found in
“‘ beds,” especially amongst the upper members of the series. The |
strata which form the surface are comprised in descending order in
the vertical section following : —Middle Coal Measures, Lower Coal
Measures, Millstone Grits, Yoredale Rocks. The Yoredale rocks
occupy the bottom, and some distance up the sides, of the valley
at Todmorden. They consist principally of shales, with beds of

502 J. W. Davis—The Valley of the Calder.

sandstone, and only differ from the Millstone rocks above them
in this: that the Yoredale rocks are mainly shales with a com-
paratively small quantity of sandstone interbedded, whilst in the
Millstone-grits, the sandstone beds of which are used for millstones
in grinding corn, the characteristic features of their composition
are the thick beds of sandstone which occur abundantly through-
out the series, and may be seen capping all the hills in this
neighbourhood. Just in the same way, the lower and upper
members of the great Carboniferous system are characterized; the
former by the immense quantities of thick-bedded limestone com-
posing it, and the latter by the frequent occurrence of beds of
coal. The one called the Carboniferous Limestone, the other the
-Coal-measures. :

By far the greater portion of the 400 square miles drained by the
River Calder and its tributaries is composed of Millstone-grits
and Lower Coal-Measures. The Millstone-grits extend from the
boundary of the county eastward to a line extended roughly from
Halifax a little west of Huddersfield, which would separate them
from the Lower Coal-measures.

The Millstone-grit rocks, with the superincumbent Coal-measures,
form parts of an immense anticlinal ridge, whose apex extends
along the summit of the chain of hills dividing Lancashire from
Yorkshire. On the side of Lancashire the dip or slope of the
rocks is very rapid, whilst that on the Yorkshire side of this
chain of hills is comparatively gentle. The woodcut on page 504,
to which I shall again refer, will explain this relationship.
Originally, the Coal-fields of the two counties were united,
and formed one large, and, we may suppose, level plain, over
which the sea occasionally encroached for long periods. During
the Millstone-grit age the sea had the best of it, and during the
deposition of the great thicknesses of shale which lay between the
grit rocks, the land was under water. The gritstones themselves
formed the sea-bed, but were near the shore, and probably washed
and ground by every advancing and receding tide—the grains of
sand composing the sandstones, when examined with the assistance
of a magnifying lens, will be found to be more or less spherical ;
the hard, sharp, corners having been removed by the constant
rubbing of one particle against another whilst they formed the sands
on the shore of this old land. A specimen from the quarry on the
edge of the moor will abundantly prove what I have said, and
if a piece of stone be chosen with large quartz pebbles inclosed,
such as very frequently occur, the rounded and waterworn form
will be easily identified. Both the sandstones and the shale are
the result of the disintegration of a still older land, just as the
Permian Limestone, which stretches in a line N. and S. across the
county, a little beyond the confluence of the Calder with the
Aire, has been derived from the Mountain Limestone of the Fell
district to the north of the Calder valley. The Millstone-grits
were probably deposited near the shore, being brought down by
rivers from the land adjoining, whilst the finer and more impalpable

J. W. Davis—The Valley of the Calder. 503

mud would be carried further out to sea, before it settled to the
bottom. This mud has formed the great bed of shale. One feature
is particularly noticeable in connexion with the deposits from this
old sea, and it is a feature that is usually remarked at a very early
period in the researches of young geologists: it is this, that there are
an extremely small number of fossils found in the beds of shale or
rock. The sandstone may be hammered by the youthful enthusiast,
where exposed in a natural escarpment, or in the numerous quarries
which occur very abundantly near Halifax, with no better result
than the acquisition of a fragment of a tree stem or a fossilized
impression of a fruit-cone of a tree to which the stem belonged ;
whilst the shales, except in a few rare instances, appear to be
absolutely devoid of organic remains. This absence of fossil
animal remains may probably be accounted for by the intermixture
with the shales of a large per-centage of iron, which was deposited
at the same time as the mud, and consequently was held in suspen-
sion by the water. Most of my readers know, that where the
water is tainted with iron, or, as it is frequently termed, is “‘cankerey,”
no fish or shells can exist; at any rate, this is the case if the
iron is present in considerable quantities. During the Millstone-
grit age, or the time at which these rocks were deposited, the waters
appear to have been very ‘“cankerey” indeed; and, as a natural con-
sequence, fishes and molluscs were either very rare, or they were
altogether absent;—only the broken fragments of the stems of trees,
brought down by the rivers from the adjoining land, being found,
as already said, in these strata. Though, however, these may be con-
sidered the general paleontological characteristics of the strata, on
the west and north of Halifax there are two or three exceptions,
which may be worth pointing out. On Wadsworth moor, about a
mile anda half from Hebden Bridge Station, a shaft was sunk in
making a passage through the hill, for the water collected on the
moorlands above Widdop to be carried to Halifax. This part is
composed of the Third Grits, and at about 300 feet from the surface
a bed of limestone occurred, which contained fish-remains, and
numerous fossil shells. If any collector would like to gather some
of these fossils, they may yet be found on the heap of shale and
stones at the mouth of the pit, and will repay a visit. The other
sections where fossils may be got, other than plants, are at Wheatley
and Ogden, beneath the Rough Rock, but these can only be found
by experienced eyes.

Turning next to the Coal-measures, we find that great changes
have taken place. There were still long periods during which the
land was under water, and thick beds of shales and sandstone were
the result, but the principal feature of this age consisted in the
formation of thick and numerous beds of Coal. I will not enter into
the question of the formation of Coal, for it is one which has engaged
much attention, and about which there are several plausible theories,
merely premising, that the coal is the result of the accumulation of
large quantities of decayed vegetable matter, which, by pressure and
some chemical changes, has been turned to the black carbonaceous

504 J. W. Davis—The Valley of the Calder.

substance with which we are all so familiar. Besides these rich
deposits of vegetable origin, with their beautifully preserved speci-
mens of ferns and other land-plants, there occurs a great number of the
fossil remains of shells and fishes which lived in the water, and also
of a few insects and labyrinthodonts which existed mainly on the
land. Specimens of these fossils may be found on almost any pit heap,
and are especially abundant in the Halifax Coal-strata and above
the Better Bed Coal of the Lowmoor district.

After this digression, we must hasten to consider some of the
physical forces which are, or ought to be, the subject of this paper.
Perhaps the most important is the great internal force which caused
the elevation of the chain of hills dividing this county from Lan-
cashire, called the Pennine Chain of Hills or the Backbone of Eng-
land. ‘This upheaval is part of an extensive system of faults which
extended primarily in two directions, viz. one running north and
south—the Pennine system of faults—extends from the eastern
side of the Lake-district southwards to Staffordshire, passing, on its
way, along the western boundary of Yorkshire. The second great
line of faults is in an easterly and westerly direction. They are
called the Craven Faults. They branch from the Pennine Faults
near Ingleton, and, proceeding eastwards along the foot of Ingleboro’,
pass behind Settle to Malham, and thence still further into Wharfe-
dale. The displacement of the rocks by these faults is very great.
In Lunedale the New Red Sandstone abuts against Silurian rocks,
and the beds must be displaced to the extent of nearly 3000 feet.
At Ingleton, the Coal-measures are placed by the Craven Fault on
a level with Silurian rocks; further east, at Malham, the Mountain
Limestone on the north is in a line with the Millstone-grits on the
south side of the fault.

In the district we are considering the break seen in the rocks is
not so distinct, but they are forced up into an anticlinal as repre-
sented in the subjoined diagram.

DraGRAMMATIC SECTION ACROSS THE PENNINE ANTICLINAL.

Lancashire. Yorkshire.

1. Mountain Limestone. 3. Millstone Grit.
2. Yoredale Rocks. 4. Coal Measure.

To understand this action it will be necessary to premise that
the earth’s crust is constantly changing its form, even at the
present time, and that, formerly, the changes appear to have taken
place much more rapidly. The strata or rocks of which the outer
surface of the earth is composed are not everywhere of the same
thickness and strength, and, consequently, are not able to bear
uniformly a lateral pressure, such as would be produced by the

J. W. Davis—The Valley of the Calder. 505

cooling, and consequent contraction, of the whole mass. Where the
earth’s crust is thinner than in other places, or, from some other
cause, happens to be weaker, it is most likely to give way, and this
seems to have been the case in the district which now forms the
range of hills westwards from Halifax. The thick beds of gritstone
and shales were crumpled up like the leaves of a book, but, being of
a hard and very inelastic nature, the grit rocks were broken asunder,
and we have the two faces of the separated rock considerably apart,
in some instances the distance has to be reckoned by miles.

Suppose there are 10,000 feet of strata, for the action extends much
lower than the rocks which are visible, lying horizontally one above
another ; then imagine a force pressing this mass from below with
sufficient strength to bend or bulge it outwards, what will be the con-
sequence? The stratum, which we will suppose to be a sandstone,
occupying the surface, will be bent upwards, until it can no longer
bear the strain, when it will burst or break into two parts, leaving a
space between. The upheaval may have been, in all probability was,
a very slow process. It is not at all necessary to suppose that the
movement was a rapid one, or that it took the form of a gigantic
earthquake or other cataclysm of that nature. The pressure may
have been gently but persistently applied, and the operation have
extended over ages. As the strata were successively strained and
broken, they would gape wide apart at the centre of the arch; each
bed of sandstone or shale, as it became elevated to the surface,
would carry those which had preceded it further and further from
the centre of rupture. This is the kind of action which actually
occurred during the elevation of the Pennine Chain. If any one,
walking from Halifax to Blackstone Edge, took the trouble to notice,
he would find that he passed over the several outcrops of the Rough
Rock and Flagstone, which presents an escarpment to the westwards,
where its existence terminates; then the series of Third Grits, which
are greater in number, but not so thick and important as the rocks
above and below; and finally the great precipitous cliffs of the
Lowest or Kinder Scout Grits would be found terminating abruptly
on the summit of Blackstone Hdge, forming the boundary of the
county.

Between each of the escarpments of sandstone, a much more even
tract would be passed over, which on examination would be found to
be shale.

We have now glanced, very briefly, over the physical contour,
the geological structure, and the internal displacement of the rocks,
forming the surface, and we know now what kind of material the
physical forces, some extinct, others in daily operation, have to work
upon.

It has already been observed that the bed of the river, from
Sowerby Bridge eastwards, runs through a series of somewhat level
plains, not unlike the appearance that would be presented by a
string of lakes joined together by a broad river. Where the structure
of these level tracts has been exposed, by sinking wells or other
means, it has been found to consist of sand containing a great

506 J. W. Davis—The Valley of the Calder.

number of rounded stones. Such a section was exposed in
digging for the foundation of the railway arch which crosses the
river at North Dean. The upper part of the section was found to
consist of sand and stones or boulders which had evidently been
derived from the sandstones of the surrounding country. The lower
part, however, about twelve feet in depth, contained, besides stones
of local origin, others which had been conveyed from very long
distances.

In many places along the sides of the valley, at Hebden Bridge,
Mytholm, Elland, and at Kirklees Park, there are deposited beds
of water-worn stones and sand. ‘Take the section at the Hlland
Cemetery for example. There is a considerable thickness of sand,
containing immense numbers of rounded stones and occasional bits
of shale. It rests on shale belonging to the Lower Coal-measures,
and reaches from the Cemetery down the hill-side towards the river,
and is cut through and well. exposed by the railway at Elland
Station. This bed is altogether different from the one in the bottom
of the valley at North Dean, and they do not present the appearance
of having been at any time connected with each other.

This deposit is just such a one as would be left by the tapping or
draining of a lake, and it appears a reasonable inference that at one
time the valley of the Calder was dammed up to the height of these
deposits, and that by some means the barrier or embankment at its
south-eastern extremity was removed and the water subsided, leaving
evidences of its existence, which may formerly have been much more
extensive than at present, in the terraces of rounded stones and sand
formerly constituting its shore, and which we now find at consider-
able elevations above the present level of the valley. Whether these
terraces are older than the boulder beds in the bottom of the valley, .
must remain an oupen question. I do not think there is sufficient
evidence to solve it at present.

The peculiar feature about the deposits exposed at North Dean,
and many other places lower down the valley, is the occurrence, in
the lower part, of blocks of granite and syenite amongst stones de-
rived from the Millstone-grits which bound the valley. How came
they there? The nearest points where they are found in situ is
either Cumberland or Wales, and consequently they must have
travelled or been carried to their present locality from either one or
the other of these localities. It appears most probable that they
came from Cumberland, for we know that a great glacier descended
along the western slope of the Pennine Chain from the Lake-district
and Scotland, and also that a considerable branch passed over Stain-
moor into Wensleydale, and found its way into the great flat country
of central Yorkshire, of which the city of York is the centre. You
may ask how this is known, and what proofs there are? In reply,
there is a mountain on the borders of the Lake-district called Shap-
fell, which is composed of a peculiar kind of granite containing very
large crystals of felspar. This peculiar granite is not found else-
where, and its occurrence in other localities, in detached and rounded
fragments, proves that it has been conveyed by some means trom

J. W. Davis—The Valley of the Calder. 507

Shapfell to the position in which it is found. The evidence that it
has been conveyed by ice is also very conclusive. Where the boulders
of Shap granite, or those from other localities, are found imbedded in
clay, they are covered with fine scratches. Now the only agent with
which we are acquainted which can scratch the stones in this pecu-
liar manner is the grinding and rubbing action of a mass of moving
ice, such as constitutes glaciers. The boulders in Lancashire and the
more eastern parts of Yorkshire are scratched in the way indicated; .
but those in the Calder valley are not scratched or striated, and
there is no evidence that a glacier ever occupied this valley. The
way these erratics appear to have got into the valley is as follows.
They were brought by glaciers into the valley of the Ouse along
with glacial clay, and deposited there. After a while the level of
the land was lowered, and the glacial deposits were subjected to the
action of the waves. The boulders were washed out of the clay, and
rolled about the bottom of the sea, until the scratches were oblite-
rated and the corners worn off.

At this time the valley of the Calder was submerged. Its channel,
subject to the fury of the waves, would soon become much deepened
and wider. The shales beneath the Grit-rock, from their loose and
incoherent structure, would prove an easy prey to the waves, and be
readily washed out. The Grit-rocks above them are broken into
huge cubes by fractures extending vertically in all directions, and, as
soon as their support was gone, these cubes of rock would fall down,
and, subjected to the action of the waves in their turn, would be
broken into smaller pieces, the corners and sharp edges removed,
and they would form the boulders we find at the present time fillmg
up the valley. Intermixed with them, the boulders of foreign
origin, washed up by currents from the not far distant valley of the
Ouse, would be deposited at the same time. After a while, on the
re-emergence of the land, the flat plains, formed as described, would
exist in very nearly the form we see them at the present day.

I have reached the concluding portion of my subject, and have
only a little more to say respecting the sub-aerial denudation that is
always in progress, at a greater or less rate.

The principal agents are rain and streams, springs and frost.
Their effects in forming the contour of the surface may be seen
everywhere. Valleys are seen cut deep into the solid rock, and still
deeper into the shales below. Landslips frequently occur, caused
by the underlying strata being washed out by springs; or the rocks,
having been saturated with water and subjected to the action of
frost, are, by the expansion of the water during freezing, forced off
in masses which lie strewn on the hill-sides. I have already
remarked on the liability to erosion by the sea of the beds of rock
in the valley of the Calder. We find, universally, that a bed of grit
overlies a bed of shale. You will find such to be the case in the
sections exposed in Copley valley.

The sandstone acts as a huge reservoir for collecting and holding
water. In wet, rainy seasons, such as we have experienced during
the past summer, the sandstones are like great sponges; all the inter-

508 J. W. Davis—The Valley of the Calder.

stices between the grains of sand full of water. The water gradually
settles or filters to the lower part of the sandstone, and, reaching the
base, it meets with the shales, and its progress is stopped in that
direction—perhaps not entirely, but nearly so. If the sandstone
occupies a hollow, it fills up until the lowest part of the shaly
rim be reached, when the water bubbles out as a spring. If, as
is usually the case in our district, the beds are inclined at a tolerably
persistent angle, the water drains to the lowest part, and is there
“thrown out” at the junction of the shales with the sandstone. A
good example of the former kind of spring occurs on Norland
Moor, at what are called the boiling wells, so named from the ap-
pearance of boiling presented by the water as it bubbles up; and for
examples where the water is thrown out by an impervious bed of
shale, you will find many along the base of the escarpment in North
Dean wood. I do not think you would be very likely to find any
on this side of the valley, because the rock dips or slopes towards
Halifax, and the water would of course follow the same direction.
This throwing out of water proves an important element in increas-
ing the width of the valley, for in its passage, minute quantities
of the shale are carried away, and the action continuing for long
periods, the foundation of the grits above is loosened or removed,
and the masses of angular-jointed sandstone fall from their position
and lie strewn over the slope below. From the peculiar manner in
which the grit rocks are jointed, they generally break away in rect-
angular blocks, leaving a still perpendicular surface to be further
acted upon. Very fine examples where a whole hill-side has been
precipitated into the valley below, may be seen at ‘“ Buckstones ”
beyond Barkisland, and also between the latter place and Ripponden.

The amount of débris carried away seawards by the River Calder
is something enormous. If you were to take a glass of water from
the river during a flood, or freshet, when the water is muddiest, and
let it stand until the matter it contained had settled to the bottom,
it would at once be seen that it forms really a large per-centage of
the weight of the whole. Next calculate the millions of gallons of
water that pass away in a day or a year, and you will be astonished
to find how many tons, thousands of tons, of our everlasting hills are
removed to another place, very likely some quiet corner at the
bottom of the German Ocean, which in ages to come will be filled up
and form dry land again. And so the cycle of changes in the
structure of the surface of the earth constantly proceeds; nothing is
fixed, nothing firm; sandstones, shales and limestones are accumu-
lated beneath the waves, are raised up and form dry land, are
subject to internal displacement, forced up into high mountains by
volcanic action, only to be again ground to powder by frost, rain,
and wind, and carried away by the rivers to form new strata in the
sea-bottom. This has been going on from the beginning, and will
proceed to the end.

J. Lamplugh—WMarine Shells in Boulder-clay. 509

TV.—Own tHE OccurreNcE oF MARINE SHELLS IN THE BOULDER-CLAY
AT BRIDLINGTON AND ELSEWHERE ON THE YORKSHIRE COAST.

By J. Lampiuce,
of Bridlington Quay.
With Notes by F. A. Bepwett, Esq., M.A., F.G.S.

iF 1874, whilst searching in the Boulder-clays south of Brid-
lington, on the Yorkshire Coast, for transported fossils, I was
greatly surprised to find a few water-worn fragments of shells
dispersed through the clay at the base of the cliff, inasmuch as all
the writers on this subject agree in assigning to the Yorkshire Clays
“no contemporaneous shells whatever,”' that is to say, no shells
actually coeval with the deposition of the clay.

From that time I carefully searched for, and preserved all these
fragments, obtaining, however, only a very limited number of
species; until a short time ago, when I had the good fortune to
witness a small exposure on the south shore, close to the town, of a
bed of clay, which is usually covered deeply with sand and shingle,
so exposed, and is very different from the Purple clay of the ad-
joining cliff. In this clay, shell-fragments were more plentiful, and
perfect, and I obtained from it the remains of about a dozen species ;
and by recent and more extensive exposures, have been enabled to
raise this number to about thirty species.

As these shelly clays are evidently very closely connected with
the ‘so-called Bridlington Crag,”? a deposit which is only partially
understood. I doubt not that a detailed account of them will be
found to possess interest.

The two distinct masses into which the Boulder-clay in this
neighbourhood is divided, are marked, not only by their lithological
characters, into ‘Blue’ and ‘Purple,’ but also by the presence
between them of a thin bed of laminated ‘snuff-brown’ clay,
which for the most part contains no pebbles whatever, being very
pure and soft, and remarkably tenacious.

This snuff-coloured clay seems to be a strictly local deposit,
occurring only in Bridlington Bay. It appears both to the north
and south of the town. ‘To the north it may be traced at intervals
along the base of the wasting cliff, for a few hundred yards north-
ward from beneath the lime-kiln. To the south it is at present well
exposed on the South Sands* between high and low-water marks, for
about three-quarters of a mile, and it then either thins out or sinks
beneath the sea, a point which can only be ascertained by careful
examination of well-borings, etc., further south; but I am inclined
to think that it will not be found to extend further than the place
above indicated, viz. halfway between Auburn and Bridlington.

Its thickness, which is evidently very variable, is 40 inches at the

? Phillips’ Geology of Yorkshire, 38rd ed. p. 164; Wood and Rome, Quart.
Journ. Geol. Soc. vol. xxiv. p. 147.

2 For some account of the Bridlington Crag see a paper by Dr. S. P. Woodward,
F.G.8., Gzor. Maa. 1864, Vol. I. p. 49.

° The beach to the north of Bridlington is locally known as the ‘“‘ North Sands,
and that to the south of the town as the ‘‘ South Sands,”

510 J. Lamplugh—Marine Shells in Boulder-clay.

point where it sinks into the beach to the south of the town. From
its position on the shore I judge that it occupies extensive hollows
in the ‘Basement’ Clay. Towards its junction with that mass
small pebbles make their appearance, otherwise it is remarkably
free from any foreign admixture.

The beds which immediately underlie this laminated clay, on
both the North and South Shore, are those to which I would more
particularly draw attention on account of their near relationship to
the mass of sand and shells known as the Bridlington Crag, which
evidently forms part of this division.

Lithologically, they consist of a dark sandy, sometimes earthy
clay, of a dark greenish-blue colour when damp, but having a more
decidedly green tinge when dried. The pebbles contained in it are
chiefly small, and consist of fragments of rocks from strata exposed
along the coast to the northward, being derived principally from the
Lias, Oolite and Chalk, with an occasional fragment from the
Septarian nodules of the Speeton Clay, and with others from rocks at
far greater distances. On the whole, it is not nearly so pebbly as
the ‘Purple’ Clay, for although in some patches pebbles are very
plentiful, in others they are nearly absent. In one or two places
there appear in it what have evidently been at some time masses of
chalk; but these are now so crushed and disintegrated as to re-
semble streaks of rough pipe-clay. _

These sandy clays form the top of beds which I identify as
the ‘Chalky’ or ‘Basement’ Clay of Messrs. Wood and Rome.
On referring to their paper,’ the reader will find that these gentlemen
only extend this division as far north as Skipsea, doubtless never
having witnessed the exposure of the beds on the South Beach
which lie just above the extreme low-water mark of spring tides,
consisting of the same ‘leaden-coloured’ clay, and characterized by
nearly the same abundance of chalk as the ‘Basement’ clay
described by them as occurring further south.

It is in the above-mentioned sandy clays on the South Shore that I
have found the shells in question in the greatest abundance, though
I have also actually obtained them from the ‘ Basement’ clay itself.

Bearing in mind the marked distinction observable between the
' ‘Basement’ clay and the ‘ Purple’ clay, exhibiting, as I think, a
distinct alteration of some kind in the nature, and possibly in the
direction of the glacial action, I was very much surprised to find
that actually in the Purple clay itself, and at heights varying up to
twenty feet above the horizon of the sandy bed already described,
there were to be seen fragments of the very same shells mixed up
with its mass, and included in the débris gathered in by the glacial
action which deposited this clay. It was these fragments of shells
which I first discovered in 1874, and which attracted my attention
to the subject at a time when the ‘Bridlington Crag’ deposit was
wholly invisible.

Having identified the fragments in the ‘Purple’ clay with the
shells found in the ‘Basement’ beds, I was led to follow up the

1 Quart, Journ. Geol. Soc. vol. xxiv. p. 170.

J. Lamplugh—Marine Shells in Boulder-clay. 511

subject more extensively; and to*my further surprise found frag-
ments of the same shells everywhere on the coast as far north as
Whitby,’ beyond which place I have not yet sought for them. And
it is remarkable, that wherever a double series of clays, as noticed by
Prof. Phillips,? can be observed, as is the case at Filey, Cayton,
Whitby and elsewhere, it is in the lower bed that the fragments are
always most plentiful and least water-worn, and this lower bed is
always the darker in colour, generally of a greenish tinge, and very
distinct from the upper bed, which is usually of a reddish brown
colour, north of Flamborough. This is especially noticeable in the
cliffs near Filey, and to the north of the last-named locality there
exist, between the two clays, traces of a bed of laminated sand and
clay corresponding, as I believe, to the ‘snuff-brown ’-coloured clay
at Bridlington. I was only able to trace this bed for a short distance ;
its thickness was about two feet.

From these facts, I think that a representative of Messrs. Wood
and Rome’s ‘Basement’ Clay will be found to exist to the north, as
well as to the south of Flamborough, but on this head further in-
vestigation is required.

The vast majority of the shells found in the sandy clays on the
South Sands at Bridlington are fragmentary. Some of these frag-
ments, even when found in the sandy clay, are quite water-worn
and rounded, but more have their angles as sharp as though newly
fractured, which is rarely the case with those present in the ‘Purple’
clay. ‘They are also more abundant in some patches than in others,
being generally most plentiful just below the laminated clay already
described. I have given below a tabular list of the species already
found by me both in these beds and in the ‘ Purple’ clay, and the
specimens have been submitted by me to Dr. Henry Woodward for
more critical examination.

That these shells are derived from the same source as those in
the ‘ Bridlington Crag’ is, I think, unquestionable; from which it
follows that this ‘Crag’ sand, with its numerous shells, lies in the
‘Basement’ or ‘ lead-coloured’ clay, and not in the upper ‘ Purple’
clay, as is suggested by Messrs. Wood and Rome.?

There is a very strong argument in favour of this, by the un-
doubted presence in the ‘Basement’ clay at Dimlington, further
south, of a similar shell-bed, which contains the same species, and is,
I believe, generally regarded as forming part of the same series as
the ‘ Bridlington Crag.’

The position of the ‘Crag’ furnishes us with another proof, for I
have myself witnessed an exposure of the upper part of the ‘ Base-
ment’ beds on the North Beach beneath Fort Hall, close to the place
where the ‘Crag’ was first discovered. The same ‘ Basement’ clay
is again exposed on the beach about 800 yards further north, con-
sisting of the same dark sandy clay with many shell-fragments, and
overlaid, as on the South Sands, by the snuff-coloured clay.

1 At which place however they had become very rare.

* Quart. Journ. Geol. Soc. vol. xxiv. p. 254.
3 Quart. Journ. Geol. Soc. vol. xxiv. p. 149.

\

512 J. Lamplugh—Marine Shells in Boulder-clay.

Again, patches of sand and gravel interstratified with and sur-
rounded by the ‘Purple’ clay, are to be found in many places
in the cliffs both to the north and south of the town, and these con-
tain no shells whatever; whereas, as already mentioned, those in-
cluded in the ‘ Basement’ clay contain them in abundance, and this
I refer to as another argument in the same direction.

In the tubes of the Dentalia, and under a perfect valve of an
Astarte, obtained from the sandy clays on the South Shore, was a
true coarse ‘Crag’ sand, showing the character of the bottom on
which these shells lived. Parts of the sandy clays (already mentioned
as forming the upper portion of the ‘ Basement’ clay), when dried,
greatly resemble the true ‘Crag’ both in colour and composition,
having the same greenish east and containing the same small black
cherty pebbles.

From these facts, and others, furnished by the direction of the
beds where they disappear beneath the town, I think it is evident
that the ‘ Bridlington Crag’ forms a part of the ‘ Basement’ and not
of the ‘ Purple’ Boulder-clay series.

The ‘Purple’ clay, which forms by far the greater part of the
whole deposit along the coast, has been so often and so well de-
scribed, that it is almost needless to enter into special details
respecting it. It is of a dark purple to the south, and of a reddish-
brown to the north of Flamborough, and contains more and larger
rock-fragments than the ‘Basement’ clay; and a large proportion of
these fragments have been derived from a distance, masses from the
Coal-measures being very abundant. The majority of the fragments
have their angles only slightly rounded, but are often scored and
scratched in all directions.

In many places in this locality, patches of sand and gravel of
considerable area (even from 80 to 90 yards in longitudinal section)
occur in this clay; and it is a noteworthy fact that, as has already
been observed, no shells are present in these patches, a strong proof
that the fragments of shells which I find in the surrounding clay
have been drifted or carried with the other ingredients of the clay,
for had they been living in the neighbouring waters during the
time the ‘ Purple’ clay was in process of formation, we might have
reasonably expected to find their perfect remains in these inclosed
sands, precisely as they are found in the sand-beds in and on the
‘ Basement’ clay.

The thickness of the ‘Purple’ clay in this neighbourhood is very
irregular, and its upper surface is deeply eroded into innumerable
hollows, which are often partially filled with a rough heterogeneous
gravel, evidently in great part derived from the clay itself, and I
agree with Messrs. Wood and Rome in concluding that the mass
has suffered extensive denudation.

Sparsely scattered through this clay from top to bottom are the
shelly fragments already referred to as being those which first at-
tracted my attention to the subject. They are more water-worn and
rounded than those from the lower beds, and rarely, or never, ap-
proach perfection, the hinge-line and umbo (the strongest part) being

J. Lamplugh—Marine Shells in Boulder-clay. 013

generally all that remains. As in the ‘Basement’ clay, these broken
shells are more plentiful in some places than in others, and where
these patches occur, the shell-fragments are scattered (not stratified)
throughout a limited area, whilst the surrounding clay is almost
destitute of specimens; but nowhere are they nearly so plentiful in
this division as in the lower.

In the South Cliff this ‘ Purple’ clay often shows indistinct lines,
suggesting stratification, and, indeed, in many places deserving that
name.

Above the gravel already mentioned as often covering the ‘Purple’
clay, lie variable and inconstant (as, indeed, nearly all the beds
above the clay are) beds of laminated sand and warp, sometimes of
considerable thickness.

The surfaces of the laminz of both sand and warp are often, as
noticed by Professor Phillips,! curiously waved, as though broadly
ripple-marked, and in one place I found the plates of warp pitted, as
though by rain. At one or two points in the South Cliff the sands
are curiously contorted and cross-bedded.

Overlying these beds is generally a mass of gravel, chiefly of
chalk, of a thickness varying in the South Cliff from half a foot to
four feet, but to the North of the town it is much thicker; and
this, except where the fresh-water marls intervene, is directly covered
by the surface soil. ;

Before proceeding to consider the conditions under which these
varying deposits were accumulated, it will perhaps aid the reader’s
perception if I lay before him a summary of the results I have now
arrived at as to the division of the Drift in this locality, placed side
by side with the typical one set forth by Messrs. Wood and Rome in
the paper already alluded to. (See table on p. 514.)

The origin of the beds lying above the ‘ Purple’ clay in this
locality is not difficult of explanation, being evidently due to
intermittent periods of stormy and quiet seas, of strong ocean
currents and placid lake-waters.

But when we come to consider the conditions under which the
Boulder-clays, with their associated Sand-beds, were formed, es-
pecially with reference to the presence of shells in their midst, we
meet with many difficulties.

On the one hand, the broken condition of the vast majority of the
shells, the worn character of many of the fragments, and the way in
which they are dispersed through the clay, would lead us to suppose
that they had been carried hither with the rest of the materials of
which the clay is formed (as, indeed, evidently has been the case
with those in the ‘ Purple’ clay).

On the other hand, the presence close by of a considerable body of °
sand and shells (some with valves still united), the entirely unworn
character of some of the fragments, and the fact of sand still
remaining in the hollow of a single valve of Astarte, forbids the
supposition that such shells could have been drifted from any
distance, unless indeed we can imagine them to have been trans-

1 Geology of Yorkshire, third edition, p. 82.
DECADE II.—VOL. Y.—NO. XI. 33

514 J. Lamplugh—Marine Shells in Boulder-clay.

Divisions adopted by Messrs. Wood Diagrammatic section of the Drift

and Rome, Quart. Journ. Geol. at Bridlington, proposed by J.
Soc. vol. xxiv. p. 147 (omitting Lamplugh.
the freshwater marls).
Gravel, principally of Chalk. Chalky Gravel.
Sands and Gravels. Sand, Warp, and Gravel.
Hessle Boulder Clay. Hessle Series absent from the
immediate neighbourhood,
unless represented by the
Hessle Sand and Gravel. A aelowen} idly iy BOUueUaee
Gravel.
Purple Boulder Clay, with Sands Purple Boulder Clay, with Sands
and Gravels, inclusive of the and Gravels.
Bridlington Crag.
Sands, with Gravel. Locally a bed of laminated Clay.

Bridlington Crag Deposit, consis-

Chalky or Basement Clay.) |. dine of Sands and Bandy Cie)
lying on and mingled with
the Basement Clay.

Chalk. Chalk.

ported in an immense frozen mass, which is rendered highly
improbable by the fact that most of the shells are of deep-water
species, and also by the position of the shells. with closed valves, and
even, as was witnessed by Mr. Bedwell (see subsequent note), in
their natural position as when alive.

The only probable solution of this problem which has presented itself
to me, is to suppose that during the earlier periods of the Glacial epoch,
a sandy sea-bottom was formed, probably founded on the already
partially accumulated ‘Basement’ clay, on which the shells in
question lived and died; and that this bottom, during a period of
extreme cold, was ploughed up and destroyed by floating-ice (coming
’ mainly from the north), which, melting, incorporated the sand and
broken shells with its own burden, consisting in part of masses
gathered on its southward journey. This disturbing process would
doubtless be often repeated, thus giving rise to the sandy clays,
which have already been described as being the stronghold of the
shell-fragments, and as forming part of the ‘ Basement’ clay.

Under this view, the Bridlington and Dimlington ‘Crag’ beds

J. Lamplugh—Marine Shells in Boulder-clay. 515

must be considered as portions of this old sea-bottom which have
escaped destruction, and I am inclined to think that the Bridlington
Crag beds include conditions, which render it probable that its great
thickness and amassed appearance may have been due to the accumu-
lating power of a huge mass of ice, which, grounding (and not, as
with the smaller bergs, merely grating) on a soft bottom, would
slowly continue its forward course for some distance, forced irresist-
ibly onward by its immense momentum and the pressure of the ice
behind, and might push before it a constantly increasing mass of
sand and shells which might attain considerable proportions ere the
whole came finally to rest. A mass thus gathered would have its
greatest thickness in the centre, and would thin out on either hand,
and this agrees with the early descriptions of the ‘Bridlington Crag’
as seen under Fort Hall. This view would also account for the
numerous single and broken shells in the ‘Crag,’ as well as for those
in which the valves still remain united, as the latter molluscs might
remain alive during the whole forward movement, afterwards re-
suming their natural attitude and becoming imbedded in that
position. I would also suggest this as a partial explanation of the
admixture of species from different life-zones, as noticed by Dr. J. G.
Jeffreys.'

Whilst slowly melting, the ice would form an impassable barrier
to the advance of the masses which followed, thus protecting the
sand and shells at its landward edge from undergoing the crushing
process, an office which might be performed by its transported
burden after the melting of the parent mass. And, indeed, some
such explanation is needed to account for the presence of these
patches of almost incoherent sand, of which the main body has
evidently been swept away.

Then must have followed a period of, at any rate local, quiescence,
during which the snuff-coloured laminated clay was deposited, the
product of still muddy waters, probably of a considerable depth.
These conditions may have been owing to some obstacle preventing
the access of ice to the neighbourhood.

This was evidently again followed by a return of the ice, this
time probably the true glacial stream from the north-west, bearing
with it huge masses from the granitic mountains of Cumberland,
and from the Carboniferous strata of the West Riding, with the
remains of a few land animals* (chiefly, perhaps solely, of the
Mammoth).

As has already been observed, the ‘Purple’ seems to be the only
clay present on the higher grounds of the coast, the ‘Basement’
beds not occurring very far above the sea-level, and it is therefore
probable that during the formation of the ‘ Purple’ clay, the lower
beds were swept away from elevated positions and carried forward,
to be re-deposited as a part of the mass then forming. It is to this
cause that I would refer the occasional presence of waterworn

1 Phillips’s Geology of Yorkshire, 3rd ed. p. 277.
* I have in my possession part of a Mammoth’s tusk from this division of the clay.

516 J. Lamplugh—Marine Shells in Boulder-clay.

fragments of marine shells in the ‘Purple’ clay (which, as I think,
evidently came from the landward), viz. to their having been
derived from the lower beds; the fact already dwelt upon of the
absence of shells from the sands included in the ‘ Purple’ clay being
strong presumptive evidence that they were not truly contempor-
aneous.

It is evident that the materials forming the Purple clay have been
dropped through waters of some depth on to the surface of the
‘laminated clay, as the nature of the latter deposit would otherwise
have caused it to be readily swept away. As it is, I witnessed one
exposure of it on the South Beach which showed remarkable con-
tortions, and to the north of the town, at the point already referred
to, beneath Sand Cottage, it is altogether absent for a short space,
the ‘Purple’ there resting directly upon the ‘Basement’ clay.
Probably the glacier, after crossing the chalk hills which form the
boundary of Holderness to the north and west, would reach deeper
waters, and there, slowly melting, drop its burden quietly through
the waters of the sea. :

In conclusion, I need scarcely add that, though in the present state
of our knowledge of the subject this seems to me to be the best way of
accounting for the presence of shells in the Yorkshire Boulder-clays,
still I anticipate that further examinations will make it necessary
for me to modify these views; for much earnest work and much
patient study has yet to be done before the origin of these clays is
really settled; and if, in the mean time, I have added but a little to
the slowly accumulating mass of information on the subject, I shall
feel richly rewarded.

List or SHELLS FROM THE Upper Part or THE ‘ BASEMENT’ CLAY (FORMING
PART OF ‘BripLineton Crac’ Deposrr) at BRIDLINGTON, AS EXPOSED IN
THE SourH Sanps. EXAMINED AND PARTLY DETERMINED BY Dr. H.
Woopwakp, F.R.S.

Those which occur also in the ‘ Purple’ clay are marked with an
asterisk. Those marked with a dagger are additional species
obtained by me from the lower clay at Filey and Cayton. Should
this bed prove to be merely a sub-division of the ‘ Purple’ clay (the
opinion held by Messrs. Wood and Rome), the shells thus marked
will, of course, go to increase the list of those already obtained from
the ‘Purple’ clay. (The prefixed c, denotes the shells which are
common. )

Pecten opercularis, Linn. c*Tellina solidula, Pulteney.
Nucula Cobboldie, Leathes. c* 4, obliqua, Sby.

* Leda rostrata, Flem. Mya truncata? Linn.
Pectunculus glycimeris, Linn. t 4, arenaria? Linn, ~*
Cardium edule, Linn. tLutraria elliptica, Lam.

», Larkinsoni, Sby.? Saxicava rugosa, Linn.
- Grenlandicum, Chemn, ? Pholas crispata, Linn.
¢ *Cyprina Islandica, Linn. * Dentalium entale, Linn.
* Astarte elliptica, Brown. Trochus ziziphinus, Linn. ?
» compressa, Montagu. Buceinum undatum, Linn.
c* ,, borealis, Chemn. tBalanus crenatus, Brug.

Wee yee 3 tintinnabulum, Linn.
Venus (°) ;

F. A. Bedwell—On the Bridlington Crag, ete. 517

Norr.—It will be seen that, with one or two exceptions, the commoner shells
alone are met with in the ‘ Purple’ clay, as might be expected from the theory here
advanced as to their origin.

The rarity of the remains of univalves in these clays is, doubtless, owing to the
character of their shells, which are more liable to be crushed than are the bivalves,
consequently, half a dozen fragmentary Columelle, and the body-whorl of a Buccinum,
are the only traces of Gasteropods that I have found. [Two fragments of deriva-
tive fossil shells may be mentioned, one of Prodwctus from the Carboniferous
Limestone, the other of Znoceramus from the Chalk. Of the 61 fragments supposed
to be distinct, more than half still remain undetermined. Probably many of these
may yield additional information when further studied.—H.W.

V.—Notes on THE Bripuincton Crac AnD BovuLDER-CLAY.
By F. A. Bepwett, M.A., F.G.S., F.R.M.S.

T is with great pleasure that I add a few remarks to Mr. Lamp-
lugh’s paper. His observations are, I think, highly important,
and will, I anticipate, be found to do great credit to the intelligence
and powers of observation of a very young and entirely self-taught
naturalist.

The story of the Bridlington Crag is given in a paper by Dr. 8. P.
Woodward in the Gzorocrcat Maeazrng, Vol. I. p. 49 (1864), which
affords details of the various notices and a valuable list of shells in
the Bridlington Crag, with an instructive table, in which the list is
compared with that of the Coralline, Red, and Norwich Crags, and
with the glacial deposits and living specimens.’

My own observations on this deposit began in 1875; in March of
that year I found a Tellina about high-water mark in a Blue glacial
clay forming the surface of the shore close to a cut leading down on
to.the North Sands, and called Sand Lane, near an Hotel called the
Alexandra. The actual cliff where the bed was seen in 1821 and
1835 has long since been washed away. That cliff lay about 150
feet to the eastward of a house now occupied by me, and called Fort
Hall. This house stands 300 yards north of the pier, on the edge of a
cliff, now bricked up with, and concealed behind, a wall erected to
preserve the house. As the spot where I found the Tellina was
over 500 yards to the north of my house along the sands, I was led
to conclude that the Bridlington Crag was of a much more extended
character than was suggested by geological writers. In the same
month Lalso found some of the same fossil Telling on the South Shore
thrown up on the sand by the waves, and fastened together by the
Byssus threads of living mussels. These had come from the mussel-
beds which extend widely over Bridlington Bay at about a quarter of
a mile from the shore, and their presence suggested an extension of
the Crag-bed considerably to the eastward and southward. At this
time, March, 1875, there was no exposure of the clay on the north or
south shores of any extent, but in December, 1875, a south-east gale
one night stripped off the sand on the North Shore before my house,
and I then saw the remains of the true Crag-bed lying on the shore,
and occupying as a horizontal section the area which had been once
covered by the cliffs now destroyed, and in which the Crag was

1 The bear's tooth referred to in Dr. Woodward’s paper is now in my possession.

518 FI. A. Bedwell—On the Bridlington Crag, ete.

originally seen. I obtained a collection of shells and black nodules
from the spot, but none of any fresh species. What I considered of
most importance was, that I saw the horizontal section of the beds
for myself, and observed that the complete bivalved shells, which
were numerous, lay horizontally and showed no signs whatever of
disturbance, and I concluded then, and still think, that they died
and lived very near to where I found them. The beautiful Nucula
Cobboldie in particular occurred, with both valves perfect, while,
delicate as it is, it had never been assailed by any force so applied
as to injure its exquisitely ornamented shell. The Pholas crispata,
which was exceedingly plentiful, was found invariably as a double
shell, and indeed I have never seen a specimen yet of a single
separated valve of that shell. Astarte borealis too, and Saxicava,
were frequently double.

The order and position of the bed on the North Sands as thus
seen by me in December, 1875, exactly corresponds with that above
given by Mr. Lamplugh for the southern extension. On the North
Shore it lies on the Blue clay, that is, the ‘Basement’ clay of Wood
and Rome. It lies below the snuff-coloured laminated clay, while the
‘Purple’ clay of Wood and Rome lies above the snuff-coloured
clay. As seen by me on the North Shore, the Crag sand, which
was very marked in its character, lay in mottled streaks in the Blue
clay. I traced it over a horizontal area of about 20 by 100 yards.
The Blue clay was always quite distinct, and there were no signs
of a transitional bed from one to the other. The fossils were mostly
met with in the sand, but I found a Cyprina Islandica in the ‘ Base-
ment’ clay itself three to four inches below the exposed surface,
and I feel quite satisfied that it lay in a ‘natural’ bed and not ina
‘derivative’ one. The bed on the North Sands, as described by
Mr. Bean, and when seen in vertical section by him in 1835 in the
exposed cliff side, was “a heterogeneous mass only a few yards long
and as many high, composed of sand, clay, marine shells, and pebbles
of every description.”! This description gives the bed a consider-
able perpendicular altitude; but whether that portion of the bed as so
seen was the result of local ocean ‘‘sweepings”’ or not we cannot now
be certain; but, from what I was told by a local geological collector,
now dead, the late J. Tindall, who saw the bed, Iam inclined to think
that it was so, for he stated quite positively to me that at the spot
seen by Bean there was no glacial clay whatever above the bed of
sand in which the fossils were found—this might indicate a creek or
recess in the then shore-line into which the accumulation had been
drifted. Prof. Sedgwick, too, in 1821, says he might easily have
filled a wheelbarrow with specimens, thus again denoting a pile of
shells heaped near together.

The independent observation which I made in December, 1875,
was soon brought to an end, as the sand rapidly returned and hid
the bed again, and it has not been exposed since. I made no use of
the observations thus obtained, because, in the face of Mr. Tindall’s
information, I was much perplexed as to the true stratigraphical

1 See Bean, quoted by Woodward (J. ¢.).

F. A, Bedwell—On the Bridlington Crag, ete. 519

position of the bed; for while he most positively assured me that
there was no Purpie clay, or, indeed, glacial clay of any kind at all
over the bed, and also that it lay above the snuff-coloured clay,
Wood and Rome, on the other hand, placed the bed in the Purple
clay itself, and yet my own observations placed it below the ‘Purple’
clay and the snuff-coloured clay, and on the ‘Basement’ clay. At
the same time, the extent of the bed, as shown by the specimens
found by me at a distance, formed an additional difficulty. But Mr.
Lamplugh’s observations have cleared up all my doubts on these
points, and the recent exposure on the South Sands, which I have
inspected, quite confirms my observations on the North Shore
in 1875. I go further than Mr. Lamplugh, and I think the South
Sands Beds are conterminous with the Northern, and that the snuff-
coloured clay is a leading guide on this point.

But the incident which strikes me as most remarkable and in-
structive in Mr. Lamplugh’s observations is the fact that he has
found fragments of Crag shells extensively scattered, through the
Purple clay, over so large an area. Many of such fragments at
Bridlington actually lie in the cliff as high as twenty feet above
the horizon in which they must have been originally deposited, if
we refer them originally to the horizon of the true Crag bed. I
could hardly believe his statement when I first heard it, because all
appearances were against it, and because I had myself hunted the
Purple clay for shells in 1875, and quite failed to find any. That
Mr. Lamplugh is right, there is no doubt, and my eyes, once
educated by him to find them, soon discovered the fragments. As
a rule, they are very small, and easily overlooked by any person
who does not read a cliff with such exhaustive and intelligent ex-
actness as characterizes Mr. Lamplugh’s observations. I have since
myself found a Tellina, nearly perfect, in the Purple clay of the
cliff, quite twenty feet above the true Crag-bed horizon, and about
600 yards distant from the spot where that bed was first seen.

The association of these fragments of shells with the Purple clay
seems to me to point to two distinct ‘sets’ or ‘tides’ of glacial
action meeting on the area which the Purple clay occupies, because,
while the boulders in the Purple clay evidence a movement from
the north-west, these fragments, to my mind, are evidence of another
movement from the eastward. I cannot at present agree with Mr.
Lamplugh’s implication that these shells represent a Crag deposit re-
moved by the glacier that brought down the Purple clay, because,
if ever these shells had got incorporated into the glacier, they would,
like everything else of so weak a structure that it removed, have
been comminuted by it, and converted into the finest débris, di-
gested, in fact, by its masticating grasp, and I should attribute the
presence of the shells rather to the long continuance of a process of
‘churning,’ that churning being the result of opposing forces, one
from the land of a glacial character, and the other from the sea
opposing the glacier with an accumulation of shore or broken ice.

The absence of boulders of any magnitude in the ‘ Basement’ or
blue clay, and the fine quality of that clay, speaks of a glacier which

520 F. A. Bedwell—On the Bridlington Crag, etc.

had either no boulders to drop, or which had dropped the larger
part before it reached the spot where the blue clay is deposited.

The ‘Crag’ shells lying on the blue clay speak of a sea deep
enough to be removed from the access of ice forces.

The presence of the ‘sand’ speaks of the proximity of a creek, or
sea-beach, or bay unassailable by ice forces (compare Speeton shell-
bed referred to subsequently).

The ‘ snuff’-coloured clay above the Crag, with its laminations
and remarkable tenacity, speaks of a glacier very powerful as a
comminuting agent, and of a transporting force which had left all
large particles of every kind behind it, and of gravity acting with-
out interference.

Then the ‘Purple’ clay represents a further variety of ice action,
which observers experienced in ice forces as exhibited in Arctic Seas
will alone be able to realize. But, as above suggested, I should refer
it to a tidal churning, a repeated freezing and thawing, and to shore-
ice just beginning to attack the débris of a retreating glacier, and in
doing so disturbing the bottom on which that débris lay, and thus
tearing up the Crag shells here and there, and even possibly in
places depositing them in a heap above the ‘snuff ’-coloured clay.

That the shore-line has been very gradually and extensively
elevated we see from the cliffs, and the Crag must clearly have
been raised several fathoms to reach its present horizon on the shore-
line, and this also supports the views expressed above.

Over the ‘Purple’ clay, and here and there in the ‘ Purple’ clay,
come the ‘ gravels,’ roughly stratified in places, but representing a
restless force which was perpetually changing the direction in which
it acted, and continually interfering with gravitation. These gravels
seem to suggest shore ice predominating, and having the coast-line
to itself, because, while the entire absence of all shells from these
gravels is very striking, the presence of minute fragments of coal
clustering together precisely as now seen on an ordinary sand beach,
is equally noticeable. Particles of coal cling together when washed
up by the sea on a shore-line with a pertinacity which has always
struck me as most remarkable, and you see numerous beds of such
fragments in these gravels, denoting a ‘vehicle of flotation,’ so to
speak. You do find coal in the ‘Purple’ clay, but it is in large
pieces, so that in these gravels I see water action of some kind
combined with a force inimical to life.

The whole line of action would thus represent a gradual elevation
of the land and a retreat of a glacier.

Closely connected with this subject is the interesting bed of recent
fossils found by Messrs. Bean and Phillips in the Speeton Cliffs, 100
feet above the shore-line.1 JI have examined this bed, which is
almost entirely concealed (masked) by a layer of ‘Purple’ clay that
has dripped down from above and covered the face of the bed an
inch thick. On picking this off, a beautiful bed of sand is disclosed
about twenty feet deep. I traced the bed to its foundation, and at
its basement found, in addition to the shells mentioned by Phillips,

1 Phillips, p. 101.

Reviews—Dixon’s Geology of Sussex. 521

a large supply of mussels. This bed in my opinion was like the
‘Bridlington Crag’ at the base of the ‘Purple’ clay. The existence
of fragments of shells in the representative of the ‘Purple’ clay
along the shore as far north as Whitby, and pointed out by Mr.
Lamplugh, is most remarkable, and suggests a wide extension of
such shells antecedent to the deposition of the ‘Purple’ clay, and
he will by further researches at Speeton, Dimlington and other
localities, be able hereafter to throw additional light on a subject to
which his present paper has given a new and special interest.

INT@RIOnzS) (Ose AMmISHIVGOenISFS —

On tHe Tuerman Sources oF Carispad, Nortu-wxst BoueEmta.
By F. von Hocasrerrer and F. Tenner. (Proceedings Imper.
Acad. Vienna, March 14, 1878.)

HE recent demolition of a house has led to the discovery of a

remarkable geological fact—the existence of a peculiar zone,
about fifteen to twenty métres broad, between the steep pyritose
granite, with frequent veins of hornstone, on which the Town Tower
stands, and the similarly pyritiferous granite cropping out beneath
the terrace of the Schlossberg. This zone is filled up with a breccia
of granite and hornstone, with thermal waters circulating every-
where within its fissures, and depositing on their inner surfaces
crusts and veinules of aragonite, some of them 14 métre thick.

The temperature of the whole zone is high, on account of the warm

water and steam issuing out of every cleft and crevice.

The situation of this breccia band, as also the direction of the
veins of hornstone in the granite, leads to the conclusion that this
thermal zone extends northwestward to the Schloss-Brunnen, and —
southeastward to the Sprudel Region proper, in the bed of the
River Tepl. Thus the views announced in 1856 by Professor von
Hochstetter, who affirmed that the chief Sprudel fissure lies in a
N.W.—S.E. direction, have again been confirmed. Count M.

REVIEWS.

Tur GroLocy oF SUSSEX; OR THE GEOLOGY AND Fossits OF THE
TrrTIARY AND Creraceous Formations oF Sussex. By the
late Frepertck Drxon, Esq., F.G.S. New Edition. Revised
and Augmented by T. Rupert Jones, F.R.S., F.G.S., etc.,
Professor of Geology, Staff College, Sandhurst; aided by Professor OWEN,
C.B.; Sir Paitie Grey-Ecerton, Bart., M.P.; and Messrs. CARRUTHERS,
Davipson, ETHERIDGE, JoHN Hyans, D.C.L., Joun Morris, NEwrTon,

Sotuas, TopLtey, HE. H. Wituert, H. WILLETT, H. Woopwarp, T. WRIGHT,
M.D., and other scientific friends.

4to. pp. xxiv. and 470. Illustrated by 64 Plates and 74
Woodecuts. Brighton: William J. Smith, 1878.
LS the early half of this century County Histories were greatly in
vogue, and as geologists are not altogether free from a tendency
to follow the prevailing fashion of the time, we find such books
appearing as ‘Phillips’s Geology of Yorkshire;” ‘‘ Woodward’s
Geology of Norfolk ;” “Mantell’s Geology of Sussex ;” ‘ Mantell’s

522 Reviews—Dixon’s Geology of Sussex.

Geology of the Isle of Wight ;” and ‘“ Dixon’s Geology of Sussex.”
Of these geological histories of English Counties, that of Dixon is
certainly among the most important hitherto attempted.

It is seldom the good-fortune of a deceased author to enjoy such
advantages for his unpublished work as fell to the lot of the late Mr.
Frederick Dixon.

That gentleman died before the completion or issue of the first
edition, which was brought out under the auspices of Professor
Owen, who kindly acted as Editor. The second edition enjoys the
advantage of the editorial direction of one who was long dis-
tinguished as the Editor of the Quarterly Journal of the Geological
Society of London, and has since prepared for the press the beautiful
memorial work of Messrs. Lartet and Christy, “ Reliquice Aquitanice”’ ;
and that remarkably compendious volume “‘The Arctic Manual,” a
most exhaustive work on polar geology and physiography.

The new edition of Dixon’s Geology of Sussex, just issued at
Brighton, promises for the work a fresh lease of life and a long list
of appreciative readers and subscribers. For the new edition is not
a mere corrected reprint of the old work, but a new work altogether.

It is gratifying to see again on the title-page the names of
Professor Owen—the Hditor of and a large contributor to the first
edition, which appeared in 1850, and Sir Philip Grey-Egerton, also
one of the original contributors; whilst a goodly list of new, but
well-known, names of geological writers has been added to the title-
page, and their contributions incorporated in the volume itself.

The leading feature of the first edition was its paleontology; this
has been greatly strengthened by the addition of much new and
important material.

For example: in Fossil Botany we have two valuable contri-
butions on Tertiary Plant-remains, and on the Flora of the Cre-
taceous formation, by W. Carruthers, F.R.S., F.L.S.

The Protozoa and Rhizopoda have also received attention. The
Foraminifera from the Tertiary and Cretaceous deposits being care-
fully described by Professor 'T. Rupert Jones, F.R.S.

The Venériculites form the subject of a special article by Mr. W. J.
Sollas, M.A., F.G.S. The typical Cretaceous Invertebrate Fossils
of Sussex are more or less fully described and figured. Their
illustration occupying forty-three plates—of these, nineteen plates
have been added since the first edition of Dixon, being the original
figures and plates from Mantell’s Fossils of the South Downs.

The Tertiary Moliusca have been brought up to date by references
to the works of F. E. Edwards and Deshayes, and by copious lists
of characteristic species. The Post-Tertiary Mollusca have also
been carefully noticed.

The Echinoderms have been partly revised by Dr. Thos. Wright,
F.R.S.E., F.G.S.

The Crustacea more fully by Dr. H. Woodward, F.R.S., F.G.S.,
who also describes and figures a new Cretaceous form.

The Fossil Fishes of the Tertiary and Cretaceous formations have
been revised by Sir Philip Grey-Kgerton, Bart., M.P., F.R.S., and

Reviews—Dixon’s Geology of Sussex. 523

Mr. E. T. Newton, F.G.S., who have added much valuable additional
matter to this section of the work.

Professor Owen has revised the Reptilian portion throughout, and
added a note on Iguanodon (p. 428).

The Antiquities—both Historic and Pre-historic—have been care-
fully revised, and also somewhat added to. The Coins, etc., by
Dr. J. Evans, F.R.S., and C. Roach-Smith, Esq., F.S.A. Whilst the
discovery of a Paleolithic implement at Portslade, and an account
of the Sussex Hill-Forts and Flint-implement Factory at Cisbury, is
given by Mr. Ernest H. Willett, F.S.A.

The weakest part of the original work was probably the geology.
This is now entirely obviated. The opening chapter gives an ex-
cellent and clearly-written account of the general geographical and
geological features of the County of Sussex by the Editor, Professor
T. Rupert Jones, F.R.S.; illustrated by a charming map of the
County coloured geologically (measuring 28in. by 10in.), with a
section from the English Channel to the Isle of Sheppey, by W.
Topley, F.G.S.

The Newer Tertiary, Post-Tertiary, or Quaternary beds of Sussex
are fully described after Godwin-Austen, Prestwich, Mantell, Bell,
and others.

The Tertiary beds of Bracklesham, etc., in addition to F. Dixon’s
description, have added to them the accounts of Dr. Bowerbank
and the Rev. O. Fisher, M.A., F.G.S.

The Newhaven Beds are described after Professor Prestwich,
F.R.S., and Mr. W. Whitaker, B.A., F.G.S.

The chapters on the Chalk Formation have been entirely revised
and modified according to our present knowledge.

The description of the Wealden and other strata of Hast Sussex
forms an entirely new chapter: whilst Mr. Topley’s account of the
Sub-Wealden trial boring, and its results to science, will form a
permanent memorial of that interesting attempt to solve the geologi-
cal structure at the base of the Wealden series. Besides the large
number of entirely new chapters which have been added to the
work, no page can be referred to which has not been enriched by
some new facts carefully and correctly placed by the judicious
Editor. Every author writing on subjects bearing upon the geology
or paleontology of Sussex since 1850, will be gratified to find his
observations quoted in their appropriate chapter; whilst the copious
index renders the work at once easy and convenient for reference.

The Editor, in every case, marks new matter added, giving the
authority cited, and so careful has he been, that even a word
inserted is put into square brackets to show that it is new.

We may fairly congratulate Mr. William J. Smith, the Brighton
publisher, who has ventured upon the undertaking of this New
Edition of “ Dixon’s Geology of Sussex,” and we can but hope that
the task so ably carried to its completion by Professor T. Rupert
Jones may be appreciated by a large circle of geological friends, not
only in the County of Sussex, but throughout Great Britain and
abroad, among the many foreign geologists who take a lively interest
in English scientific literature. f

524. OBIT U.A BN.

—_—_>——_

SIR RICHARD JOHN GRIFFITH, BART.,
LL.D., F.R.S.E., F.G.S., M.INST.C.E., M.R.I.A.
Born 27 SepremBer, 1784; Diep 22 Sepremper, 1878.

N the early days of the present century, Geology, like the “ Dark
Continent,” was but little known, and every man was his own
guide in the new science. Roads were few and imperfect, and
guides were wanting; whilst barriers of ignorance and prejudice
blocked the way at the very outset.

Now all is changed—the pioneers of our science have done their
work grandly and well, and prejudice has given place to favour and
public recognition. But by far the larger number of those grand
original workers and thinkers, to whom we owe so much, have
laid down their hammers and pens and have passed away.

To the names of William Smith, Greenough, MacCulloch, De la
Beche, Scrope, Lyell, Sedgwick, Murchison, Phillips, must now be
added that of the venerable Sir Richard Griffith.

Born in Hume Street, Dublin, on the 27th September, 1784,
Richard Griffith was, at an early age, placed by his father in the
best public school in that city; and later on, in 1797, he proceeded
with his studies under the tuition of the Rev. Mr. Moore, of Donny-
brook. As soon as the completion of his education permitted, he
obtained a commission in the Irish Artillery ; but when, after the
Act of Union had passed, the Irish Artillery became merged in the
British forces, his father conceived it to be more to his son’s advan-
tage that he should resign his commission and devote himself to
Civil Engineering and Mining. In order to prosecute his studies
more successfully, he visited Cornwall, where he had the good for-
tune to obtain an early reputation for acumen by discovering at the
Dalcoath mine rich ores of nickel and cobalt, which had previously
been rejected as of no value. Lord Dunstanville, the owner, was so
delighted at the discovery, that he proposed to make Lieutenant
Griffith general manager and superintendent, but he modestly de-
clined, preferring to extend the range of his knowledge by a care-
ful survey of the mining districts of Derbyshire, Yorkshire, and
Northumberland. Thence he continued the pursuit of practical mining
and surveying into Scotland, studying fora time in Edinburgh under
such eminent men as Sir James Hall, Professors Playfair, Jameson,
Hope, and others. Here his rising abilities were held in such high
estimation, that, at the early age of 23, he was unanimously elected
a Fellow of the Royal Society of Edinburgh. In 1808 he returned
to Ireland, and commenced his professional career by the publica-
tion of a work, under the auspices of the Royal Dublin Society,
entitled ‘Geological and Mineralogical Examination of the Leinster
Coal-field,” which was completed in 1814. In 1809, the Commis-
sion appointed to inquire into the practicability of draining and im-
proving the peat-bogs and mosses of Ireland, selected Mr. Griffith to
be one of their engineers. In 1812 his Surveys and Reports were
published by authority of Parliament. He was at this time ap-
pointed to succeed the late eminent Chemist and Mineralogist,

Obituary—Sir Richard John Griffith, Bart. 525

Richard Kirwan, as Inspector-General of His Majesty’s pines in
Ireland.

After the famine in the South of Ireland, in 1822, he was em-
ployed by the Marquis Wellesley, then Lord-Lieutenant, to improve
and construct roads in the counties Cork, Kerry. and Limerick, a
task which, had it been Mr. Griffith’s sole achievement, was carried
out so successfully as to merit the highest praise. Whilst engaged
on this laborious undertaking, he constructed two hundred and fifty
miles of new roads through a mountainous district, previously quite
inaccessible, and the favourite resort of ‘“‘ Whiteboys,’’ who made it
their stronghold, and defied the laws.

Before the Ordnance Survey was established, Mr. Griffith was
appointed General Boundary Surveyor, and so long ago as the year
1812 the first outlines were attempted of one of the most valuable
and important works with which his name is identified, namely, the
preparation of a Geological Map of Ireland. No labour seemed to
Griffith too great in order to carry out this great work satisfactorily,
and also its subsequent revision; indeed, throughout his life, he
never lost his interest in it. Four editions of it were published, the
latest of which was issued in 1854.

In 1828 he was appointed Commissioner for the General Survey
and Valuation of Rateable Property, while his services were used
by the Government in connexion with various other commissions,
such as the Shannon Commission, ete. In 1848 he was appointed
Deputy Chairman of the Board of Works (Dublin), and in 1854 he
became Chairman, an office which he held until his death, although
relieved of its active duties. It should be mentioned that he was
twice elected President of the Geological Society of Ireland, and
took a very active part in its proceedings, and in promoting the
study of geology in his native city.

Dr. Griffith records that the Meeting of the British Association in
Dublin in the year 1835, gave a fresh impulse to his labours, and
in 1838, Major Larcum, R.E., of the Ordnance Survey Office,
Dublin, constructed for him an entirely new Topographical Map of
Ireland on a scale of four miles to an inch, “the most accurate Map
of Ireland that has hitherto been published.” (See Quart. Journ.
Geol. Soc. 1854, vol. x. p. xx.) It was on this map that Dr. Griffith
finally laid down the fourth and revised edition of his stratigraphical
colouring and geological boundary lines, and the first copy of which
he exhibited to the Geological Society of London in February, 1854.
At that Anniversary Meeting the Council awarded Dr. Griffith the
Wollaston Palladium Medal, in recognition of his valuable services
to geology by the completion of his Geological Map of Ireland.

In 1858 Her Majesty conferred a Baronetcy upon him in acknow-
ledgment of his long and valuable public services.1. One who knew
him well, Mr. G. H. Kinahan, M.R.1.A., writes :—“ Griffith had extra-
ordinary powers of endurance, memory, and foresight. He usually
travelled by night, and after spending the night in a post-chaise
would do a hard day’s work in the field. Scarcely twenty years

1 Much of the foregoing is taken from the Dublin Daily Express, Sept. 27, 1878.

526 Obituary—Sir Richard John Griffith, Bart.

ago he walked over the Dingle Mountains with a party of young
men, yet Sir Richard, then over 70 years of age, was as active as the
youngest, and endured a pitiless downpour of rain in his swallow-
tail coat perfectly unconcerned.”

“Like Sir William Logan in Canada, wherever Sir Richard
Griffith went he made friends, and these, throughout the whole of
Treland, served as an army of amateur helpers, who supplied him
with information as to rocks and fossils. He had a wonderful
memory for names and places, and could describe minutely each
quarry and section in any given locality, long years after he had
visited it.”

‘More than half a century has passed away since Griffith com-
menced his Geological Map of Ireland. At that time there were no
Ordnance Survey sheets to use as a basis on which to lay down his
geological work, as bit by bit he made it out and pieced it together.
The existing maps were very incorrect, and they had to be corrected,
or maps had even to be made, before they could be used.

“One striking feature about the work is that it is all the result of
his own personal observations, and none of it was done by guess-
work, yet it was all done before a railway existed, and when even
good roads were rarely to be met with.

“The period now called Paleozoic had then but three divisions—
the centre was ‘ Old Red Sandstone,’ below which all the rocks were
called ‘Transition,’ or ‘Greywacke,’ and those above ‘Carboniferous.’ ”

[Sir Richard Griffith is said to have doubted the propriety of re-
taining the so-called “Old Red Sandstone” series as a separate
formation in Ireland, believing it to be made up partly of rocks of
Silurian age, and partly of those of the Carboniferous period.
However this may be (whether in deference to the opinion of other
eminent geologists, or partly as his own conviction), he certainly
retained the Old Red Sandstone formation on his map.

He refers with evident confidence to his successful sub-division of
the Irish Carboniferous system into a seven-fold series, five belonging
to the Carboniferous Limestone, and two to the Coal (Quart. Journ.
Geol. Soc. 1854, vol. x. p. xxi.).]

«The tracts which Griffith believed to be Silurian, although coloured
as Old Red Sandstone, are the mountainous area about Fintona (Cos.
Tyrone and Fermanagh), the rocks of the Curlew Mountains (Cos.
Sligo and Roscommon), and the Slieve Moyle rocks (Co. Mayo).
Subsequently when Du-Noyer found plants in the Silurians of West
Cork, which were pronounced by Salter to be allied to Carboniferous
forms, Griffith still adhered to his opinion, and said: ‘The plants
may be Carboniferous, but the rocks are Silurian.’ Plants allied to
Carboniferous forms have since been found both by American and
Continental geologists in rocks of known Silurian age, so that in all
probability Griffith was correct.

«When the late Dr. Oldham had proved the existence of Cambrian
rocks in Dublin, Wicklow, and Wexford, Sir Richard Griffith stated
that rocks of the same age existed in Donegal and Galway. The
Donegal rocks have still to be worked out, but as regards Galway

Obituary—Sir Richard John Griffith, Bart. 527

Griffith was quite correct, for beneath the rocks considered by Prof,
Ramsay to be the basal group, equivalent to the English Cambro-
Silurians, there are over 7000 feet in thickness of rocks that can
only be deemed to be of Cambrian age.” —(K1INaHAN.)

So lately as the week in which Sir Richard Griffith died, Prof.
Edward Hull, F.R.S., the Director of the Geological Survey of Ire-
land, addressed a letter to him from Glengarriff, informing him that
as regards the age of “the Dingle Beds” (which had been referred
by Griffith to the Silurian formation and are coloured as such in his
Map of Ireland (edit. 1855), but which the officers of the Survey
held to be of uncertain age, and had coloured them intermediate be-
tween Old Red Sandstone and Upper Silurian), he was now fully
convinced “of the correctness of Sir R. Griffith’s views regarding the
age of the Dingle, Killarney, and Glengarriff Ranges.” (“ Nature”
October 10, 1878, p. 627.) But the venerable geologist never lived
to rejoice in this confirmation of his views. History will doubtless
do justice to the great merit of his work.

We owe to Sir Richard Griffith a most valuable contribution to
palzontology, namely, a “Synopsis of the Characters of the Carbon-
iferous Limestone Fossils of Ireland, by Frederick M‘Coy, F.G.S.”
(Dublin, 1844, 4to. pp. 208, 29 plates ; reprinted in 1862, with table
of fossils and localities.) This valuable work, containing, in addi-
tion to the fossils previously known, descriptions and figures of 450
new species, was prepared and published at the cost of Sir Richard
Griffith, and represents the specimens in his own cabinet, collected
either by himself or his friends, from the Carboniferous Limestone
system of Ireland.

We hope that this valuable collection may find a resting-place in
one of the public museums in Dublin.

The collowing is a list of papers published by Sir Richard Griffith,
Bart. :

Reson relative to the moving bog of Kilmaleady in the King’s County.—Tilloch,
Phil. Mag. lviii., 1821, pp. 70-73.

On the Principle of Colouring adopted for the Geological Map of Ireland.
—Dublin Geol. Soc. Journ. ii. 1839, pp. 78-90.

On Mr. Weaver’s paper on the Mineral Structure of the South of Ireland.—
Phil. Mag. xvii. 1840, pp. 161-179.

On the Geological Relations of the several rocks of the South of Ireland [1839].
—Geol. Soc. Proc. iii. 1841, pp. 136-138.

On the Syenite Veins which traverse Mica, Slate and Chalk at Goodland Cliff
and Torr Eskert, to the south of Fair Head, in the County of Antrim.—Trans.
Geol. Soc. 2nd series, v. p. 179. Proc. Geol. Soc. ii. p. 223. Phil. Mag. 3
series, vill. p. 559.

On the Geological Relations of the several Rocks of the South of Ireland.—
Proc. Geol. Soc. iii. p- 136. Phil. Mag. 3 series, xv. p. 536.

On the True Order of the Succession of the Older Stratified Rocks in the
neighbourhood of Killarney and to the North of Dublin.—Phil. Mag. series 3,
xvi. p. 161; xvii. p. I6I.

On the Geological Map of Ireland.—Rep. Brit. Assoc. 1835, Sect. p. 56.

On the Leading Features of the Geology of Ireland.—Rep. Brit. Ashe 1837,
Sect. p. 88.

On the Geological Structure of the South of Ireland.—Rep. Brit. Assoc. 1838,
Sect. p. 81. Karst. u. Dech. Arch. xvii. p. 388. L.u. Br. N. Jahrb. 1844, p. 828.

Statement of the Fossils which have been Discovered in the Several Members

of the Carboniferous or Mountain Limestone of Ireland.—Rep. Brit. Assoc. 1842,
Sect. p. 51.

528 Obituary—Prof. Harkness and Mr. T. Belt.

On the Distribution of Erratic Blocks in Ireland, and particularly those of the
North Coasts of the Counties of Sligo and Mayo.—Rep. Brit. Assoc. 1843, Sect.
p- 40.

On the Lower Portion of the Carboniferous Limestone Series of Ireland.—Rep.
Brit. Assoc. 1843, Sect. p. 42.

On the Old Red Sandstone, or Devonian and Silurian Districts of Ireland. —
Rep. Brit. Assoc. 1843, Sect. p. 46.

On the Occurrence of a Bed of Sand containing Recent Marine Shells, on the
summit of a Granite Hill, on the Coast of the County of Mayo.—Rep. Brit.
Assoc. 1843, Sect. p. 50.

On certain Silurian Districts of Ireland.—Rep. Brit. Assoc. 1844, Sect. p. 46.

Notice respecting the Fossils of the Mountain Limestone of Ireland, as com-
pared with those of Great Britain, and also with the Devonian System.—4to.
Dublin, 1842.

A Synopsis of the Characters of the Carboniferous Limestone Fossils in
Treland.—,to. Dublin, 1844.

On the Order of Succession of the Strata of the South of Ireland, particularly
with reference to the Killarney District, Co. Kerry.—Dublin Geol. Soc. Journ. iii.
1849, pp. 150-160.

On the Lower Members of the Carboniferous Series in Ireland.—Brit. Assoc.
Rep. 1852 (pt. 2), p. 46.

On the Copper Beds of the South Coast of the Co. of Cork.—Dublin Geol.
Soc. Journ. vi. 1853-55, p- 195.

Explanation of the Principles of Colouring the Geological Map of Ireland.—
Dublin Geol. Soc. Journ. vii. 1855-56, p. 294.

On the Sub-divisions of the Carboniferous Formation of Ireland.— Dublin Geol.
Soc. Journ. vii. 1855-57, p. 267.

On the Remains of Fossil Plants Discovered in the Yellow Sandstone at the
base of the Carboniferous Limestone Series of Ireland.—Dublin Roy. Soc. Journ.
i. 1856-57, p- 313-

On the Relation of the Rocks at or below the base of the Carboniferous Series
in Ireland.—Brit. Assoc. Reports, 1857, pt. 2, pp. 66-67.

On the Stratigraphical Relations of the Sedimentary Rocks of the South of
Treland, of which the Glengarriff and Dingle Districts are composed, etc.—Dublin
Geol. Soc. Journ. viii. 1857-60, p. 2.

On the Occurrence of Posidonia Becheri in the Calp of Rush, Co. Dublin, and
of Posidenia lateralis in the Carboniferous Slates of Kinsale, Co. Cork.—Dublin
Geol. Soc. Journ. viii. 1857-60, p. 75.

An Additional Permian Locality, Co. Tyrone.—Dublin Journ. Geol. Soe. viii.
1857-60, p. 173.

The Localities of Irish Carboniferous Fossils, arranged Stratigraphically, ete.—
Dublin Geol. Soc. Journal, ix. 1860-62, p. 21.

On the Boulder-Drift and Esker Hills of Ireland, and on the position of the
Erratic Blocks in the country.—Brit. Assoc. Reports, xli. 1871, (Sect.) pp.
98-100.

Proressor Rosert Harkness, F.R.S., F.G.S., late of Queen’s
College, Cork.—This eminent Geologist died suddenly, from heart-
disease, in Dublin on Oct. 3rd.— Nature, Oct. 10th, 1878.

Mr. Tuomas Bett, C.H., F.G.S.—The death of this excellent
Naturalist, Observer, and Geological Writer, is announced in Nature,
Sept. 26th, 1878.

We hope to publish Memoirs of both the above geologists in the
December Number.—Ep1r. Gron. Mag. ‘

Errata.—The Rev. Maxwell H. Close requests to be allowed to note the following
corrigenda in the last Number of the Grou. Mac., for which he is not responsible.
P. 452, line 15, for “ probable,” ead “improbable” ; line 18, for ‘‘ molecular,” read
“molar”; p. 453, line 6, dele “at that time”; p. 454, line 1, remove inverted
commas from sentence following “figure.” Mr. Close says, “I did not read out the
note; it contains a strange blunder of mine, but unfortunately I forgot to tear it
away when giving the MS. to be printed.” ’

THE

GEOLOGICAL MAGAZINE.

NEW SERIES)” DECADE. [ity VORLIN:
No. XIL—DECEMBER, 1878.

Qs IS eI YA) Se DEI Oa bays

—_—_—_

J.—A Posstpte EXPLANATION OF THE NortuH Devon Szrcrion.

By Prof. Epwarp Huu, M.A., F.R.S., F.G.S.;
Director of the Geological Survey of Ireland.

HILE engaged this autumn in reinvestigating the relations

of the “Dingle Beds” and “Glengarriff Grit Series” to
the Silurian rocks below, and the Old Red Sandstone above, in the
South-West of Ireland, my mind naturally reverted from time to.
time to the Devonian district, and the succession of its beds, upon
which there has recently been so much discussion, and to which
the late Professor Jukes devoted so much time and labour. With
him I agree in believing that the key to the solution of the De-
vonian problem is to be found in the structure of the South of
Ireland, though with reference to the actual explanation which
he proposed, I can only see my way to a partial concurrence.

The full and lucid descriptions of the formations of North Devon
which we possess are sufficient to enable any one acquainted with
the rocks of the South of Ireland to recognize representative beds,
even if they may not have visited Devonshire itself. For those
who are in this position there are the writings of authors, of which
Mr. Etheridge has given a complete summary, and, more recently,
those of Professor Jukes and Mr. Htheridge himself.

Pending a personal visit, I venture to offer a contribution towards
the solution of the Devonian problem, which, to some extent, meets
the views of recent writers, though somewhat different from any yet
proposed. And, in the first place, I may observe that, as far as
investigations have yet gone, they have not resulted in discovering
the great east and west fault which Jukes supposed to range across
North Devon, repeating the red rocks and overlying slates and
limestones of Foreland, Lynton, and Ilfracombe. On the other
hand, we have the elaborate investigations of Ktheridge, both palzon-
tological and stratigraphical, all going to show that there is an
approximately unbroken sequence from the Quantock and Lynton
sandstone on the north into the Carboniferous beds of the centre of
the country (Quart. Journ. Geol. Soc. vol. xxiii.).

DECADE II.—vVOL. V.—NO. XII. 34

590 Prof. Hull—On the North Devon Section.

With reference to the bearing of the structure of the South of
Treland on that of Devonshire, I] have come away from the examina-
tion of the rocks in the former district strongly impressed with two
or three leading conclusions.

First.—That the “ Dingle beds” (Glengarriff grits, etc.) belong
in all probability to the Upper Silurian series, a view maintained
by Sir R. Griffith, Mr. John Kelly, and others, including several of
my colleagues of the Geological Survey of Ireland.

Secondly.—That not only in the Dingle promontory, but every-
where in the South of Ireland, these Upper Silurian beds are
separated by a wide gap (represented by denudation and uncon-
formity) from the true Old Red Sandstone; and thirdly, that the
Old Red Sandstone is conformable to the overlying Lower Carboni-
ferous series ;—a view generally accepted amongst Irish geologists.

With these Upper Silurian beds (‘“ Dingle beds and Glengarriff
grits’), consisting of conglomerates, red and green grits, and purple
slates of great thickness rising into the highest elevations in Ireland,
striking generally eastwards until they pass unconformably below
the Old Red Sandstone of Cork and Waterford, the question arises,
may we not expect to find them represented in the Devonshire
Section? This, to my mind, seems in the highest degree probable,
to say the least of it. Then, again, another question suggests itself :—
May there not be some beds in the Devonshire Section which, in that
region, occupy the gap between the Upper Silurians and the true
Old Red Sandstone in the South of Ireland? If so, what part of
the series would they represent? Clearly, beds older than the
‘‘Upper Old Red Sandstone,” which underlies conformably the
Lower Carboniferous beds, and newer than the Upper Silurian ;
that is to say, beds in the position of the Marine Devonian beds of
Devonshire, including the “Lynton Slates” and Ilfracombe and
Mortehoe groups."

Now, the base of this fossiliferous Marine Series is evidently and
admittedly ‘the Lynton Sandstone” (Foreland group). A series of
unfossiliferous hard red and green sandstones, or rather grits, with
some slaty beds, of which the base is not seen, and which is over-
laid by the Lynton slates, full of marine fossils. Jukes describes
them in terms strictly applicable to the Glengarriff grits and slates
of Kerry, viz. “as thick massive grits of green and red colours, with
purple slates, the whole being similar to many parts of the Old Red
Sandstone of the South-western portion of Ireland,”? by which he
means the “Dingle Beds” or “ Glengarriff Grits,” by him supposed
to be “Old Red Sandstone.” Of the beds to which Mr. Jukes refers
there can be no doubt; for when he wrote the above, great un-
certainty prevailed regarding the real age of these beds. This
uncertainty is now nearly removed—and geologists in this country
are coming round to the views of the late Sir R. Griffith stated

1 T use the terms adopted in Woodward’s ‘“‘ Geology of England and Wales.”
2 Additional Notes on the Grouping of the Rocks of North Devon and West
Somerset, p. 9, Dublin, 1867.

Prof. Hull—On the North Devon Section. 531

above—that the Dingle Beds and Glengarriff Grits are really the
highest members of the Upper Silurian Series, and altogether dis-
connected from the true Old Red Sandstone. To this question I
hope to return on a future occasion.

Reverting, however, to the Devonshire section, I must also assume
that the ‘“ Pickwell Down Sandstones” are the representatives of
the true ‘Old Red Sandstone” of the South of Ireland. They are
described as consisting of red micaceous sandstones, shales, and con-
glomerates, a description which would answer fairly well for the for-
mation representatives of which I suppose them to be. Mr. Etheridge
ealls it the ‘“‘ Upper Old Red Sandstone,” and possibly the upper-
most beds at the junction of the ‘Baggy and Marwood slates
(Cucullea Zone)” may represent the formation of this name in
the South of Ireland (‘the Yellow Sandstone” of Griffith) with
Coccosteus, Anodonta Jukesii, and Adiantites Hibernica. Jukes men-
tions some beds near Drayton and Slade, which strongly reminded
him of the Kiltorcan beds of this stage in county Kilkenny. It
will probably be found on a careful resurvey of North Devon, that
the Pickwell Down Sandstones are somewhat unconformable to the
underlying beds.

Assuming the identity in position of the Pickwell Down Sand-
stones with the Old Red Sandstone of Ireland, it follows that the over-
lying Marwood slates and Pilton Beds, consisting of slates, sometimes
calcareous, with bands of limestone and sandstone, characterized by
Cucullea trapezium, etc., are the representatives of the ‘‘ Lower Car-
boniferous slate and Coomhola grits” of the South of Ireland; and
in this identification, I have much confidence that Jukes was perfectly
correct. If anything was required to confirm it, we have the plant
evidence in the presence of Lepidodendron and Calamites in Sloly
quarry. The general representative sections of the rocks in the
South of Ireland and in North Devon, according to the above
interpretation, would therefore be as follows (see table at the end of
this article, p. 552) :—

Should it ultimately appear that this classification is correct
—or approximately so—it will be found to confirm the views of
those geologists who consider that there is a general ascending series
from the Coast of North Devon, beginning with the Foreland and
Quantock Hill group, and terminating with the Culm-measures and
Barnstaple Beds. On the other hand, it will confirm Jukes’s views
regarding the Carboniferous age of the so-called ‘“ Upper Devonian
Beds” from the Baggy and Marwood slates upwards, and also his
determination regarding the age of the ‘“ Pickwell Down Sand-
stones.” It also explains the unconformity between the Old Red
Sandstone and “the Dingle Beds ”’—so remarkably prominent in the
Dingle Promontory—and it determines the relations between the
Marine Devonian Beds and the Old Red Sandstone in Devonshire.
In offering the above observations towards the solution of the
question, and pending a personal inspection of the North Devon
beds, I would, meanwhile, invite the opinion of those geologists
who have the advantage of knowing Devonshire already.

O82 Prof. W. Keeping—Geology of Aberystwyth.

SuGGEstreD CoMPARISON OF THE SUCCESSION or Formations In Nort Drvon
AND THE SoutTH or IRELAND :—

DESCENDING SERIES.
Nort Drvyon. Sout or IRELAND.

2 b. Pilton and Barnstaple Beds.—Cal-)

Bes careous sandstones, grey shales | Lower Carboniferous Slate and
Ae and slates with nodular lime- “ Coomhola Grits.’”’—Grey and
Mea 5

> = stones. Fossils—Marine. > olive green slates and grits
2S | a. Baggy and Marwood Slates.— | with calcareous bands. Cu-
Eee Slates and sandstones with Cu- cullea and other fossils.

culled, ete.

b. Drayton and Slade Beds.—Green- 6. Upper Old Red Sandstone (“ Yel-

Ou Rep SanpsTonE THON CARBONI-

wm
8 ish and yellowish sandstones low sandstone, Griffith ’’).—
= (passage beds). Yellow and greyish flaggy
4 sandstones, with Anodonta
oe Jukesti, Adiantites, etc., and
a5 fish.
Ss a. Pickwell Down Sandstone.—Red a. Old Red Sandstone.—Red and
a micaceous sandstones, shales, brownish-red sandstone with
2 and conglomerates. bands of shale and conglomer-
eS). : ate at base.
F glossy slates, ete.
z c. Ilfracombe Group. — Shales and
ee slates with limestones, with
oe Stringocephalus, ete. Not represented in Ireland.
ce b. Hangman Grits.—Red and grey }Great gap and unconformity at this
Ss grits, shales, and sandstones. stage.
SS ie ly ynton Slates. — Gritty slates,
i shales, and sandstones, with

fossils. Spirifera, Orthis, Fene-

Ks
|
|
;
|
L
{d. Mortehoe Group.—Grey and purple )
L stella, Bellerophon, etc.
(
|
4
|
U

S a. Linton Sandstone (Foreland a. Dingle Beds and Glengarriff
elie Group). — Reddish, green, and Grits. — Greenish Grits, red
aa purple grits and slates.— Plants ? and purple slates and con-
je “ Fucoids,’ and Annelid bur- glomerates. Plant-like mark-

wal rows only. ings and Annelid burrows.

IL.—Norss ON THE GEOLOGY oF THE NEIGHBOURHOOD OF
ABERYSTWYTH.

By Water Keepine, B.A., F.G8. ;
Professor of Geology in the University College of Wales.

N England and Wales there is scarcely any area whose geological
structure is so little known as the neighbourhood of Aberystwyth.
Every year a stream of geologists passes through the northern parts
of the Principality, through the varied old-volcanic districts of
Snowdon and Cader Idris, and the rich collecting grounds of the
Berwyns: and another such stream takes its course to the southern
borders along the far west Pembrokeshire coasts, being guided by
the careful work of Dr. Hicks. The border counties too are in
many places attractive enough, for there it was that Murchison first
saw the order of the Silurian - rocks, and there also the best-preserved
fossils are found. Llandeilo, Builth, Woolhope, May Hill, Malvern,
and Wenlock have long yielded rich harvests to paleontologists.

Prof. W. Keeping—Greology of Aberystwyth. 533

These several districts form the boundaries which, together with
the sea of Cardigan Bay, make up a complete zone enclosing the
large area of Mid Wales—an area which is very commonly regarded
as a wilderness to the geologist, and a desert to the paleeontologist.
Nowhere in this country are fossils abundant, and the rock-beds are
in places marvellously contorted. To study this group of Mid
Welsh rocks, we could not do better than to make Aberystwyth our
head-quarters, and thence traverse the country in various directions.

First, taking a walk along the shore either to the north or south of
the town, the cliffs offer a splendid view of the Aberystwyth group
—a great series of bedded rocks in such violent twistings and
puckerings as astonish even the most unobservant of people. I
know of no better place throughout England or Wales for observing
these rock contortions.

Faults and Joints.—The few dislocations or faults seen along the
coast are very small; for example, those just south of Aberystwyth
Castle, and again between Aberystwyth and Clarach; but larger
faults, mostly in an east and west direction, are doubtless indicated
by the many lead veins to the west.

The rock structure known as jointing may. be well studied in this
neighbourhood. A glance at a quarry in any rock will show that
the rock material is not all in one solid mass, but is divided up into
blocks, sometimes very regularly, sometimes quite irregularly, so
that masses may be removed with the wedge and lever without ever
breaking across a stone. Such natural planes of division are known
as joints. The extent of these joints varies greatly; at Allt Wen,
south of Aberystwyth, some very fine examples are seen cutting
vertically and cleanly through the rocks, so that in those places
where they have been exposed by landslips, which are frequent,
they stand out like huge walls of well-built masonry. We may see
them running thence straight down the cliff and continuing their
course across the shore out to sea.

At the other extreme we have small and frequent jointing, hard
to distinguish from cleavage, as is seen in some of the grit-beds near
Llanilar. One cannot detect any such regular persistency in the
direction of the lines of jointing as we shall afterwards find in the
case of cleavage ; on the other hand, there is a more intimate rela-
tion between the jointing and the sloping of the rock-beds. Some
of the hard sandstones of Plynlimmon are jointed into rude columnar
masses.

Rock varieties—The rocks of Mid Wales are of few kinds, and
they are remarkably similar throughout the district. Beds of grit
of that characteristic Cambrian type mixed with clayey material
known as Greywacke (originally a muddy sand), sometimes coarse
grits, hard sandstones, and occasionally a pudding-stone or con-
glomerate bed (originally pebble beds), are the forms in which the
ancient sandy deposits occur, whilst the clay deposits are now found
as irregular shale, mudstone rab (a mudstone breaking into small
fragments when exposed), wrack (a coarser larger form of rub),
pencil rab (breaking into long fragments—as seen under Allt

584 Prof. W. Keeping—Geology of Aberystwyth.

Wen), clay-slate, a coarse black slate, and ‘“ Bastard” slate. Many
varieties of each of these may be collected, and amongst these
varieties we will first notice the frequent presence in them of that
golden or brassy mineral Iron Sulphide. This may be found in
nests under Craiglais, or in cubical crystals further north towards
Borth, and up the valley east of Eglwys Fach, where they hand-
somely stud some of the grits.

Nearly everywhere the coarser grits show some angular brown
spots on their weathered portions, and in some places, especially
at Mynydd Bach, white crystals are seen. These are, both of them,
crystals of felspar, or the remains of such crystals, and they are
interesting proofs either of the presence of older igneous rocks
close by, from the degradation of which they were obtained, or they
may even be the records of volcanos themselves then existing some
miles away ; for the crystals of felspar are not rounded as they would
be if driven for a distance by water-action, but remain still angular.
Microscopic analysis shows that much of the felspar belongs to the
plagioclase group.

Fossils and Curious Rock Surfaces.—Wherever the crystals of iron
sulphide occur, we are more likely to find fossils; at the Morben
Quarry, near Machynlleth, especially, we find the fossils themselves
converted into this bright metallic mineral. Very few of these
fossils have yet been recorded. Many years ago, in 1846, Professor
Sedgwick found fossil shells at the Devil’s Bridge, which were
identified by Mr. Salter, and published in the Quarterly Journal
of the Geological Society in 1846 (Lond.), and I do not know of
any other list. But we need not go so far for organic remains ;
the quarries around Aberystwyth, at Cefn Hendre Cwm, and Bryn
y Mor, themselves yield those fossils called Graptolites (Graptolites
Sedgwicki, G. lobiferus. Rastrites, Dictyonema, and others), long,
slender, toothed, saw-like organisms, each ‘ tooth” being the cell
of a small “zoophyte” somewhat less highly organized than a
common coral. At the Morbern Quarry beautiful specimens of
Graptolites are abundant, including a spiral form. A species of
Diplograptus may be found in the Llyfnant Valley, near Glandovey ;
Dictyonema and Dendroid Graptolites at the Devil’s Bridge; Fora-
minifera (Dentalina,: Rotalia, and Textularia) occur at Cwm Symlog,
and shells (mostly Orthoceras) at Corris, Taren y Gesail, and
Steddfa Gurig. There is a curious branching calcareous organism,
which may perhaps be a Polyzoon, found in the quarry at Craiglais,
and ranging eastwards as far as Plynlimmon.

But besides these fossils, there are other structures which will
force themselves upon the attention of the visitor before he sees
such an organism as those we have noticed above. Curious
markings, straight, round or irregular; branching, curved, or con-
torted; and in great variety. Some of these are undoubtedly the
tracks of worms; Llampeter, for instance, is noteworthy for its
fine specimens of Nereites Sedgwickii and N. Cambrensis; and

1 This Foraminifer was first discovered by the Rev. J. F. Blake, M.A., F.G.S.
See Gzox. Mac. Dee. II. Vol. III. p. 184.

Prof. W. Keeping—Geology of Aberystwyth. 535

again around Pont Erwyd the beautiful Nereites Macleani is quite
abundant. All these show clearly the marvellously tortuous tracks
of marine worms; centrally we see the depression made by the
body, and at the sides are the marks of the numerous lateral “feet”
with their bristles. Nemertites and other supposed worms are also
found.

Others amongst these markings are quite as evidently marine
plants—Algze—seaweeds. There is one well-marked type of these
that is particularly noteworthy, consisting of a stalk, sometimes
several inches long, from the summit of which branches are given
off in a fan-shaped manner. Of this type there are three species—
a large, a small, and a medium-sized form. There are also long
strap-like seaweeds.

Many others of the queer irregular markings! so abundantly
found may have had their origin primarily in some organism, or
the trace of some organism,” to serve as a nucleus around which
material has gathered by ‘“concretionary action.” We may to some
extent explain this concretionary action as a force which causes
particles of the same nature to collect together into masses; thus
it was that the myriad flinty particles originally in the chalk were
dragged together to form flints, so the particles of sulphide of iron
came together to form large crystals or nests about Aberystwyth,
and so also many of the irregular masses in our local grits have
had their origin.

““ Cone in Cone” Nodules.—Amongst the best-marked of these
concretions are the lenticular nodules, which occur in zones, well
seen along the coast between Aberystwyth and Borth. They are
sometimes so close together as to unite with one another; but good
specimens, with circular contours, about 2in. to 10 in. in diameter,
are not difficult to find. The peculiar and pretty structure known
as ‘‘cone-in-cone” is invariably found over the exterior of these
nodules. We may liken this “ cone-in-cone” structure to crowds
of miniature conical sugar-bags packed one into the other, and all
the packets arranged side by side around the stone, moreover every
sugar-bag has its sides delicately crimped. The bases of the cones
are directed externally, the apices inwards. Single cones may be
extracted with the knife, usually about a quarter, or half an inch
long, but larger ones are sometimes found. ‘This is not an organism
—not a life-structure, and we must look to the results of crystalline
forces for some similar appearances to explain its origin. Now
ordinary calespar is often found in a fibrous form, and I have seen
layers of such mineral where in some places the fibres run parallel
to one another, but in other spots they are directed towards some
common point so as to form a cone. Here then was cone-in-cone
structure produced by the arrangement of the crystal fibres of calcite.

Carbonate of lime, carbonate of iron, and carbon itself in the
form of coal, exhibit this structure, often on a much larger scale

1 It should be noted that these marvellous surface contortions and other markings,
so characteristic of the Mid Wales rocks, are convex on the under surface of the
flags and grits. 2 Mostly seaweeds.

536 Prof. W. Keeping—Geology of Aberystwyth.

than we find it at Aberystwyth. Our specimens probably contain
carbonate of iron, for the brown oxide is frequently found colouring
exposed weathered specimens. d :
There is a remarkable contorted structure very common in our grit
rocks, which may be well seen in the blocks brought from Ystrad
Meurig Quarry, and now forming the stone pier at Aberystwyth.
Concretionary action may perhaps explain this in part, but I am
disposed to look to water as the more probable agent ’—the water
percolating through the more sandy layers after the deposition of
the rock, and so altering the arrangement of the particles.
Arrangement of the great Rock-masses, and their Age.—The regular
alternation of old sandy and muddy deposits (grit and shale) is very
striking around Aberystwith, and for about five miles to the east.
Professor Sedgwick called these beds the Aberystwyth Group. Next,
further to the east, a great series of slaty rock succeeds—the Metal-
liferous Slate Group; then at Plynlimmon: we reach another grit
group (Plynlimmon Group), in thicker beds than at Aberystwyth,
and with some quartz-conglomerates (part of the Plynlimmon Group
of Sedgwick). i
Altogether these several rock groups make up an enormous thick-
ness of strata. An actual measurement of only that part of the
series between Aberystwyth and the Devil’s Bridge gave us a thick-
ness of over three and a half miles.”
Of all these deposits the Aberystwyth rocks are the lowest, for all the
beds to the east slope over them, just as the lines here drawn towards

B incline over those nearer A. AINSI:

As we walk to the north or to the south, we shall find again that
the rock deposits slope away from, and are therefore newer than,
those at Aberystwyth. Even to the west, too, the beds slope away
seawards, as may be seen when we walk along the shore, or notice
the cliff sections. So that Aberystwyth is the centre of what is
known to geologists as an Anticlinal axis—the axis of a huge dome
of rock-masses. The slope to the north and to the south is much
less steep than to the east, so that an almost north and south line of
outcrop has its axis running through Allt Wen, Aberystwyth, and
over Constitution Hill on to Clarach.

The exact geological age of the Aberystwyth rocks cannot yet be
fixed. That they are extremely old is clear enough, for just as we
See in the little diagram above, that the beds at A, slope under those
at B, so we might have drawn a long series of sloping lines on to C,
where C should represent the coast of the south-east of England ;

* This contorted structure forcibly brings to mind the irregular contortions which
are so generally found in foliated rocks, such as mica-schist. The same cause may
well have produced the structure in both rocks. : oe

* The great apparent thickness of a group of rocks in the Moffat District of
South Scotland has been explained by Mr. Lapworth as produced by frequent sharp
foldings, by which the beds are repeated over and over again. But we have no
evidence that such an explanation can be applied to the rocks between Aberystwyth
and Plynlimmon.

Prof. W. Keeping—Geology of Aberystwyth. 537

for this is the grand order of English rock strata, that the beds to
the west slope under those to the east; the beds of the east over-
lying those of the west. But again, it is the primal law of strati-
graphical geology that the undermost strata are the oldest ; and by
this law we learn that the rocks of Cambria are the lowest and
oldest of rocks—they are the foundation over which England has
been built up. The very lowest deposits of the Cambrian System
are, however, not to be found here at Aberystwyth, though they may
be reached and seen in grand development by a day’s excursion to
Barmouth. Our local rocks are much newer than those of Bar-
mouth, and very probably belong to the lower part of the great
Bala Group of Prof. Sedgwick. By the Geological Survey they
were placed in the Lower Llandovery Group; and there are
apparently conflicting facts which have yet to be put into harmony.

The suite of fossils as recorded by Salter from the Devil’s Bridge
has a Lower Llandovery facies, but other fossils, such as the
Dictyonema, the Dendroid Graptolites, and the Rastrites, seem to be
represented by similar, if not identical forms in the Llandeilo
Group of the Longmynd district; the curious Polyzoon (?), the
worm tracks and other markings, are near to those of the Skiddaw
Group in the English Lake District, and some similar markings are
also found in the Arenig country. Whilst recognizing then the
present imperfection of the evidence, we may reasonably place the
Aberystwyth rocks in the Lower Bala Group of Sedgwick.’ Litho-
logical resemblances afford us little help, but we may notice that
some of the Silurian rocks of North Wales (in the Denbighshire
Group) have a great likeness to those of Aberystwyth.

Slates and Slaty Structures.—It is proper to notice here, in further
detail, those mineral masses which are so important as sources of
mineral wealth to our district. These are principally the slates and
metals as worked in slate quarries and metalliferous mines.

Slaty structure has been superinduced upon clayey and other
rocks after their deposition by the action of lateral pressure. It is
reasonable to our common sense that when a number of lenticular
bodies are subjected to lateral pressure, and are allowed some slight
freedom of vertical motion, they will get more or less arranged face
to face, with their broad faces at right-angles to the pressure. So,
too, if we wished to subject a lot of pennies to heavy lateral pressure,
we should first arrange them in rows face to face, and apply the pres-
sure along the course of the rows, for in this arrangement they are best
able to sustain the pressure, and this arrangement is the most stable
under the circumstances. Just so it is with the old clay deposits.
We actually see under the microscope the particles of slate with

1 N.B.—These rocks are very commonly known as Silurian. Through a series
of errors, Sir Roderick Murchison felt compelled to absorb Sedgwick’s Cambrian
almost entirely into his Si/wrian System. But so good and true a name as the
“Cambrian System,” as applied to a great and natural group of rocks, honestly and
successfully worked out, must not be allowed to be degraded into the appellation of
a small part of that system. Such a course is not only unfair to our great leader in
Cambrian geology, but is also, as I believe, a hindrance to geological science. As a
name, too, the change would be unfortunate.

538 Prof. W. Keeping—Geology of Aberystwyth.

their long axes arranged parallel with the surface of the slate.
Those great forces which puckered up the rocks into such extra-
ordinary contortions, also caused that arrangement of the particles
of rock in virtue of which the rock now splits or ‘ cleaves” into
thin slates.’

It is reasonable to expect that some of the transition stages
between the old sea muds and the well-formed slates should in
some places be found; and Aberystwyth is such a place. There is
no good slate within some few miles of the town, but the clay
group of rocks is represented by irregular shale, rubbly rab, soft
slate, and “bastard” slate; very commonly however traces of cleavage
are seen in the shale more or less clearly marked, and “rab” is in
many cases produced by cleavage, often combined with joints and
bedding planes.

Along the shore near Clarach well-marked slate may be seen. It
is here soft and useless, but, nevertheless, it is true slate, for it may
readily be seen that the lines of division are thin, and regular in
direction, and that they cut across the planes of stratification at a
high angle.

The constancy of the direction of the lines of splitting, as seen
upon a horizontal surface (7.e. the strike) is a very well-known and
characteristic feature of cleavage; in the neighbourhood of Aberyst-
wyth this direction is about N.N.E. to §.8.W., varying only a little
northwards or southwards. This being the constant direction (with
rare exceptions) of the exposed edges or strike, the slate may stand
vertical, or may slope W.N.W. or E.S.E. ; most commonly the dip is
about 80° W.N.W. When the planes of bedding are at all nearly in
the same direction as the cleavage, the latter will accommodate itself
to the lines of bedding, and run along them. Such a change in the
cleavage is very prettily seen in a road-side cutting between
Glandovey and Machynlleth.

In practice, however, much caution is required in registering the
dips of cleavage planes, because of the phenomenon known as
“surface deflection.” Very generally we find on the sides of the
hills that the slates have more or less toppled over in the down-
hill direction, so that a surface slate which should be vertical
now inclines inwards and downwards towards the centre of the
mountains. The numerous small openings for slate and lead, and
the deep water-gulleys enable us to find the true direction.

This phenomenon is by no means confined to slates, but is also
well seen in the thick beds of limestone and sandstone, in basaltic
columns, ete. To explain its origin it is quite unnecessary to appeal
to the force of glaciers and the grounding of icebergs, for it is
obvious that, given such loosening agents as the roots of plants, and
especially the alternate freezings and thawings during winter,

1 The rock structure we have been describing above is known as cleavage, and a
slate is the result. Shale is a rock which splits into thin layers along planes pro-
duced by the circumstances of its deposition. As arule, slate is harder and more
regular than shale, and especially slates often split across the planes of bedding ;
shale rarely does so.

Prof. W. Keeping—Geology of Aberystwyth. 539

gravity is constantly at work to take advantage of these shiftings,
and to drag the slate or rock-bed over; in the course of their
frequent loosenings they naturally come to topple over more or
less down the hill.

Large slate-workings may be visited in the neighbourhood of
Corris, other good quarries are worked at Taren y Gesail and S.W.
of Machynllyth (Morbern Quarry), whilst numerous small openings
for local use are met with about Machynllyth, Tregaron, Strata
Florida, Goginan, and, indeed, throughout the country of the
Metalliferous Slate group.

Metalliferous Veins.—A glance at the Geological Map of Cardigan-
shire will show that the majority of the mineral veins run more or
less parallel to one another in an E.N.E. and W.S.W. direction,
roughly speaking, and we may also distinguish a separate set
running more nearly from N.W. to §8.E. So also, as we overlook
the mines themselves from a vantage point, we may often notice
that they are arranged in lines—those in the same line being probably
all workings in one vein. Descending into an ordinary mine, we
shall find that the vein is a vertical, or nearly vertical, wall-like
mass of mineral matter, sharply defined on both sides by the walls
of the vein, which are often found to be polished and striated.
The thickness of the “lode” or vein varies, but is very commonly
about four or six feet; lateral offshoots are frequent. The vein
consists of vein rubbish, spars, and ore. The “ vein rubbish ” is
mostly hard slate-rock, like the country rock around; the spars are
almost exclusively quartz, and the ores are usually lead (lead
sulphide, PbS) zine, or black jack (Zn S) or copper (copper
pyrites Cu, S, Fe, §,). Silver is found in valuable quantity, but it
is not distinguishable in the vein of itself, being mixed with the
lead in small proportions. Practically, however, its presence 1s
detected in the rough state, for the “silver lead” is commonly a
paler and more finely crystalline ore than that in which silver is
scanty.

It is probable that these veins are in the lines of old faults or
rock dislocations, by which open fissures were produced, and after-
terwards the cavity was filled in with spars and rubbish from the
sides and “country rock” around, and the ores were brought by
sublimation from helow.

The Records of the Ancient Glaciers.—We must now leave the solid
geology of the country to notice what is the nature of those newer
formations which are commonly classified under the heading of
“surface deposits.” And here the relics of the Great Glacial Period
first claim our attention, since they form the oldest of this surface
group, and also because they are so very conspicuous.

We need only go to Aberystwyth Castle Ground, and pick up the
stones on the cliff over the railings, to find at once those peculiar

1 Tt is remarkable how very frequently a lead mine is found at the head of a
valley, and again they are frequent along the sides of valleys. This is probably due
to the metalliferous veins, being lines of comparative weakness, so determining the
lines of action of subaerial denuding forces as to produce valleys.

540 Prof. W. Keeping—Geology of Aberystwyth.

subangular stones with the characteristic scratches, which the
geologist recognizes as the result of glacier action. Aberystwyth
is built upon that deposit, and every valley in the neighbourhood
has its abundant share.

The best exposure of these old glacial formations is about seven
miles south of Aberystwyth, where we find a most interesting
section. The cliffs here have been eaten away by the sea, and also
by small streams from the land, into the most fantastic forms:
deep narrow gulleys, down which we may with some difficulty
climb, here and there over-arched above or again opening out into
a “chine.” Jn the cliffs lie colossal masses, large blocks, stones,
and pebbles, imbedded in a matrix of coarse sandy clay, irregularly
mixed together, without any such arrangement as invariably obtains
in ordinary water-formed rocks. Nearly every stone has its face
or all its faces scratched and smoothed.

All the stones are such as may have come from within a few miles
of where they now lie, grit, greywacke, slate, shale, and mudstone,
with a few quartz boulders, forming the great porportion. They were
brought down and deposited here by local glaciers—rivers of ice,
which had their birthplace in the higher hills inland, and stretched
out their long ice-arms and ice-sheets in all directions towards the
lower ground.

Many a Welsh valley has a most-typical glacial aspect—a broad,
open, half-amphitheatre-like head, which formed the “gathering
ground” of the glacier where the snows principally collected, and
below an open valley U shaped in section, its sides regular, and
every feature rounded. For in this part of its course below the
head the snows had become changed into hard blue ice moving
slowly and steadily down, either to its end where it was melted
in the lower grounds, or to reach the sea where it was broken
up and carried away in the form of icebergs. Such ice-streams,
grinding their way down the valleys, would allow of no asperities,
no sharp features, but all was smoothed and rounded.

Wherever a side stream, now entering the old glacier-rounded
valley, has more recently cut back for itself a deep bed, its angular
valley with rough irregular sides form striking contrasts to the
glacier-carved surfaces. This is very well seen from the Devil’s
Bridge road, looking towards Pen-y-ffrwd, where a small stream
leaps down the steep valley side facing you; and every one who
walks much into the country around may find every day fresh
examples of the two contrasting types of valley.

Yet more exact tracks of the local glaciers remain in the rounded
rock bosses known as “roches moutonnées,” and the polishings,
scratchings, and groovings still left upon the solid rock. Such
traces of glaciers are well seen in many places around Aberystwyth,
such as the valley above Eglws Fach, the Ystwyth valley on the
Lisburne Mine private road, in the Rheidol valley at Ty Llwydd,
by the road-side between Pont Erwyd and Steddfa Gurig, in the
mine works, on the side of Plynlimmon above Steddfa Gurig,
and in the Domen valley. In all these places polished and striated

Prof. W. Keeping—Geology of Aberystwyth. 541

rock-surfaces are seen as well marked as in an Alpine valley where
the glacier has but lately retired. These are the tool-markings of
our ancient glaciers and they are marvellously well preserved.

But these Welsh glaciers were not confined within the limits of
the present valleys; they often overspread such boundaries to open
out upon the lower hills, and, it may have been, there to form a von-
tinuous sheet many miles in breadth. The hills around Aberystwyth
are from about 300 to 700 feet high, and over all these the glacial
deposits of stony clay, etc., may be seen with all their usual charac-
ters, and with numerous large transported blocks left there as the
glacier retired. On the higher ground to the east of Llanfihangel
crowds of these blocks cover the ground, and above Cwm Symlog
large masses are seen stranded at above 1000 feet.' These blocks
too are often strewn over the sides of valleys, where they were left
at the edges of the glaciers as they dwindled away.

It is remarkable that those puzzling mounds of false-bedded
sand and gravel, known as Osar in Scandinavia, were distinguished
by the ancient Celtic peoples both of Scotland and Ireland. By
the former they were called Kames; by the latter Eskers.

Nor were the people of that other great branch of the Celtic
race, the Cymri, wanting in the same extraordinary discrimination
in detecting these ridges; for here in Wales the name Esgair or
Escair is by no means uncommon,—evidently the same word as
the Irish Esker. For example, we may point out the name “ Hsgair
Annos,” which designates a characteristic Esker east of Rhyader.?

Near Llanrwsted Road, Aberystwyth, an enormous Hsker is seen
stretching its broad back more than 100 feet high across the
valley of the Ystwith, like a terminal moraine. Through it the
river has cut its present channel down to and into the solid
Cambrian rock.

Two railway cuttings afford us excellent views of the structure of
this Esker. At once we are struck with the great irregularity and
steep false-bedding of the deposits, i.e. the layers of material were
not thrown down horizontally ; and, looking closer at the anatomy
of the section, we find combined evidences of both water and ice-
action. There is the stratification of water; the false-bedding of
rapid currents and eddies; and there are the subangular and well-
scratched stones, telling us of the work of ice. Many of the pebbles
are of the ice-formed types, but some are perfectly rounded.

We have no evidence of any modern encroachment of the sea
up to where this giant Esker lies. J look to the combined actions
of ice and water, and perhaps snow, to explain its formation. It
is contrary to experience that the sea should pile up a huge bank
of materials so little water-worn, with so many of the stones still

1 All these blocks are from the local grit and hard shale-beds, or more rarely a
conglomerate from Plynlimmon. In the Ystwyth Valley, and towards Machynlleth,
a pale- coloured hard granular and felsitic-looking rock occurs, whose origin is not
yet known to me.

2-It seems probable, from subsequent observations, that this local name Zsgazr,
may sometimes have been applied to mounds of a different origin and structure trom
that of Eskers properly so called.

542 Prof. W. Keeping—Geology of Aberystwyth.

retaining their glacial strize and their subangular contours, as in
this Esker.

As the glaciers retired, the melting of the ice and snows gave rise
to exaggerated river action, so that the valleys were swept by rapid
water-currents, often carrying loads of stones stolen from the
glaciers and their moraines. These materials, being rounded as they
rolled along the bed of the stream, were roughly arranged and
deposited above the proper glacial formations, over which we now
usually find them. Such formations are well seen in the cliffs some
few miles south of Aberystwyth, and at Clarach; also the coarse
pebbly deposits at Tregaron, through which the river has cut, and
perhaps some others of our river deposits belong to this stage.

We have not yet found in our neighbourhood any evidence of
such a succession of glacial periods, interglacial periods and great
quaternary submergences as are described in other areas. All the
phenomena we observe here may well have been produced during a
late period by local glaciers.

We have as yet no means of teiling the absolute date in years at
which our islands were subjected to these glacial conditions, but we
have a very marked record of that date, if we could but read it, in
the gorges which streams and waterfalls have cut since the glaciers
disappeared. For we have seen that the glaciers left their banks
all smoothed and rounded, and it is most conspicuous how far the
more rugged and angular beds which have been since produced by
the streams of water extend back beyond them. Here then is
our record, and when we can determine the rate at which the streams
cut back their beds, then we shall easily calculate how long it is
since glacial conditions existed here.

The Latest Geological Phenomena.—Since that time comparatively
little geological deposit has been added to the country. The rivers
have formed flat lands of pebble beds, loam, and sand, and have
again cut down deeply through them, as is well seen in the Rheidol
Valley near Ty Llwydd: but these deposits contain no fossils except
here and there a piece of wood. Their pebbles are to a great
extent derived from the denudation of the glacial deposits,—most
barren records.

In many places however where quiet or stagnant water was kept
in, extensive beds of clay and peat have been formed, the peat
uppermost. The Tregaron Valley is a good example of this, for here
a very pure and homogeneous soft blue clay is found together
with the overlying peat well developed. Very generally such
deposits yield many interesting fossils,—shells in the clay and bones
of mammals in the peat, but that is not the case here. I have only
met with two antlers of the Red Deer (Cervus elaphus) in the clay
near Borth,'! and have not found any animal-remains in the peat.
This is the more strange, because we know that many animals have
lived in this region during the more recent periods, whose remains
one would expect to find; such, for instance, as the Beaver, whose

1 One of these was presented to the University College Museum by Mrs. Davies
of Antaran.

Prof. W. Keeping—Geology of Aberystwyth. 543

last British stronghold was in the Teifi; the Bear, whose former
presence is proved by such names as Pwl cenawen! (the cubs’ pool) ;
and the Otter, which is still hunted in the streams. Trees are
however often found well preserved in the peat; their roots and
trunks may always be seen where turf-cutting is going on and
sometimes fine trees are found. In the neighbourhood of Tregaron
the wood is still used by the carpenters, and portions of trunks are
very commonly made into rollers for the fields.

The best exposure of these prostrate trees is the submerged forest
at Borth. Here at low water hundreds of ‘stools’ with their roots
still fixed in the old soil are seen; while prostrate trunks and
branches are abundantly scattered around. ‘The Oak, Pine, and
Beech are most numerous. The soil upon which they grew was
very peaty, and was made up to a great extent of reeds, flags, and
other vegetable matter matted together. The decomposition of
the tissues of these plants gives rise to gases which are now being
evolved, and sulphuretted hydrogen especially may be recognized by
its fetid odour when the peat is disturbed. Such an old land
surface is found throughout Cardigan Bay, extending from below
low-water mark to a distance of several miles up the valleys. At
Clarach it is occasionally laid bare, and it is nearly always exposed
at Tan-y-Bwlch, south of Aberystwyth.

Beneath the submerged forest at Borth there is a blue clay con-
taining marine shells (Serobicularia piperata and Rissoa pallida),
in great profusion.

In these various deposits on the Borth shore we have the evidence
of three changes in the relative level of land and sea. First the
old Cambrian rocks were submerged to allow of the deposition of
the Scrobicularia clay ; then came an upheaval carrying the latter
deposit above high-water mark at least, when the peaty formation
was produced in the swampy flat; and, later on, the beech and pine
forests flourished. But again came a depression, which submerged
the forest and killed the trees, many of which probably stood long,
as bare, leafless skeletons, to be blown down and strewn irregularly
along the shore and over the sea-bottom. Only the stools now
remain erect; every tree is prostrate.

Physical Geography.—The connexion between the physical geo-
graphy of a country and its geology must everywhere be most
intimate ; and their correlations are generally as easily explained as
they are evident. Rocks have their characteristic surface features
as well as their characteristic fossils. The rich low country with
its many little hills of Tertiary counties, and the grand alternating
series of limestone ridges and fertile plains of the Secondary dis-
tricts of England, are equally foreign to our neighbourhood. In a
country composed of such enduring rocks as prevail in Mid Wales,
we are sure to find a more grand and rugged type of scenery, which
is only repeated in those areas whose geological structure is similar
to it, such as the Lake District of England and parts of Scotland.

1 The name of a farm-house near Penllwya.

544 Prof. W. Keeping—Geology of Aberystwyth.

Amongst these, too, Mid Wales has its own physical characteristics,
which distinguish it from other Cambrian districts. We miss
especially the high precipitous escarpments with their scree slopes
below, and the sharp peaks of the more northern Cambrian areas,
and the scenery is altogether less rugged than those. This is suffi-
ciently explained by the homogeneous character of the Mid Wales
rocks, the rare occurrence of thick deposits of hard grit and
quartzite, and the absence of igneous rocks. It is not till we reach
Plynlimmon, and again go still further east to the neighbourhood
of Rhyader, that we find more massive grit-beds and conglomerates,
and here the bolder features of steep rugged hill-sides and preci-
pitous escarpments are found.

We have already, when dealing with the Glacial period, referred
to that moulding of the surface features by the action of ice which
has so profoundly modified the character of our scenery, but we may
here dwell longer upon those more angular valleys which have been
produced by the action of streams since the ice disappeared. Such
valleys are, as a rule, best developed in the neighbourhood of water-
falls, for there the cutting power of water is at its maximum. At
the Devil’s Bridge, Pont Hrwyd, and below Llyn Rhyddnant,
especially, deep chasms have been cut out by the long-continued
action of the water as it rushes down and hurls the stones, large
and small, like cannon-balls and gun-shot against the sides and
bottom of its bed. The characteristic water-cut sides are well seen
in the “ Devil’s Punch Bowl” of the Devil’s Bridge, and the same
appearances should be noticed all up the sides of the chasm. They
are well seen lower down on the left bank of the waterfall above
the iron foot-bridge; thus presenting to us the most convincing
proof that the gorge has been cut out by the water itself, and is not
a gaping fissure produced by violent earth movements.

The Caradoc waterfall, between Traws Coed and Strata Florida,
is remarkable in that the slope of the fall corresponds with a sudden
fold in the rock-beds themselves,—a coincidence which is most
unusual.

Those cylindrical holes known as ‘ Pot-holes” are well seen
along the Rheidol in many places, as at the Parson’s Bridge, Devil’s
Bridge, and higher up around Pont Hrwyd. These are good illus-
trations of that mode of working by water with the aid of hard
stones which we have already noticed. At the bottom of the Pot-
holes some stones are sure to be found, and it will at once be evident
that as the current of water flows over the hole, a spiral motion is
set up in the water of the Pot-hole, so that the stones are carried
round and round the bottom of the hole, always grinding their way
deeper and deeper down. It is interesting to notice that in this way
water may carve out great hollows below its level of outflow. The
holes vary much in size; some are no bigger than beer tumblers, in
others one might hide oneself.

The Plane of Marine Denudationn—Whoever has gone to the top
of the higher mountains of England, Scotland, Ireland, Germany,
Switzerland, etc., must have noticed that the great spread of country

Prof. W. Keeping—Geology of Aberystwyth. 545

around him looks much more regular than he would have expected
from his previous knowledge of the lower grounds. He may have
considered the whole country mountainous, and quite irregular; but
now, from his elevated position, he is surprised to find how very
level and regular it looks. Now he sees all around a great plain, in
which the valleys appear as huge furrows ploughed out. The same
feature, viz. the regular height of the summits of most of the hills,
and their comparative evenness, may also sometimes be observed as
you look at a mountain system from a distance, when the tops of a
number of mountains are seen to be so many points in the same
straight line. Such a plane is known as a “Plane of Marine
Denudation”; and it may be well seen from the top of Aran
Mowddwy, Cader Idris, Snowdon, Plynlimmon, or nearer home
from the top of the hill above Cefn Hendre, Aberystwyth. The
height of this plane in Cardiganshire is from 500 feet to about 750
feet, gradually sloping upwards to the Plynlimmon mountains.

This plane of marine denudation tells us of a period, far removed
from our age, where the sea gradually cut inland its level shores and
sea-bottom, levelling all down and leaving only the higher mountains,
as Plynlimmon, Cader Idris, etc., as isolated islands. Just in the
same way the sea is now cutting down another plane; it is slowly
eating away Constitution Hill, and every other hill along the coast,
and reducing all to one Jevel—a modern plane of marine denudation.

Lakes and their Modes of Origin.—Another feature which Mid
Wales has in common with most mountain districts is its numerous
lakes. A number of these may be visited from Aberystwyth, though
most of them are not easily accessible, for they are generally situated,
not in the valleys, but upon the summit plains of the hills. They
are depressions in the great plane of marine denudation. Such are
Llyn Eiddwyn, L. Gynon L. Fyrddyn, L. Gron, L. Egnant, L. y
Gorlan, L. Hir, and Llyn Teifi, etc. The five latter are the best
known under the name of Teifi Pools, and they will serve well as
illustrative examples of the most common type of lake in Mid Wales.

Far up in the hills we find these irregular bodies of water with their
walls all formed of solid rock. They generally run more or less
along the strike of the rock-bed, their sides are not lofty (rarely so
much as 100 ft.), and in many cases at least their depth is not great.! *

There are three principal ways by which lakes may be formed,
(1) by the action of ice scooping out a hollow in the solid rock;
(2) the formation of a dam across a valley, as by the moraine matter
piled up at the end of a glacier; and (8) by earth movements,
especially depressions.

The Teifi Pools, together with the great majority of our Mid
Wales lakes, belong to the third class. Here we have not

‘* A lofty precipice in front,
A silent tarn below,”

1 The depths of many of the lakes are not yet known to me.

2 The visitor must take care to distinguish the natural lakes from the artificial
reservoirs of water made by the lead-workers to serve for a steady supply of water
to their water-wheels.

DECADE II.—YVOL. V.—NO. XII. 30

546 Prof. W. Keeping—Geology of Aberystwyth.

which is so characteristic of class (1), there is no gathering ground
here for the snows to collect in and form a glacier. Again, the con-
tinuity of the solid rock all around decides at once against the theory
of a moraine dam. No—in Mid Wales we have a crowd of lakes
formed by vertical depressions of the solid rock. Very generally
the rock-beds are seen sloping down towards the lake on two or
three sides, and on one side there may in some cases have been a
break in the continuity of the rock-—a slowly-formed local fault.

We have, however, a good example of an ice-formed lake in
Llyn Llygad-y-Rheidol under Plynlimmon. The position of this
lake is highly favourable for the denuding action of ice. Snows
gathered abundantly upon the heights above, and a glacier certainly
did descend into the valley in which the lake now lies; it is then
highly probable that the ice here scooped out a hollow. This may
well be, but we have besides an obvious cause for the existence of a
lake here in the bank of glacial moraine which is now seen running
across the valley at the foot of the lake, and through which the stream
has cut for about 25 feet. Llyn Llygad-y-Rheidol is then a good
example of our class (2), but it is not unlikely that the scooping
power of ice (class 1) may have deepened its rock-bed.

The Beach Pebbles.—We must add a few words about the stones of
the Aberystwyth beach. Most of these are, of course, rounded pieces
of the grit, greywacke, and shale of the cliffs around, but these are
scarcely noticeable to the searcher among the more conspicuous hard
pebbles which are so numerous and so various. In a few minutes
we may pick up quartzites, conglomerates of various colours, felsites,
mostly quartz felsite, several varieties of granite, hornblendic
granite, syenite, many species of greenstones, and numerous meta-
morphic rocks. We may also find a chalk flint or perhaps a
more valuable “pebble” in the technical sense of that word as
used by the lapidaries. The homes of many of these pebbles
are not yet known to me; the flints and agates might have
come from the chalk and basalt of co. Antrim in the N.H. of
Treland, and other pebbles might have been picked up along the
Carnarvon peninsula and carried southwards by currents, but I have
not yet been able to identify any such with certainty. On the other
hand, it may be that in the Glacial period, while the snow and ice
covered the land, icebergs freighted with rocks from other lands
floated down the Irish Sea, and dropped their burdens of foreign
stones down to the sea-bottom so as to form a Boulder-clay. Such
a deposit, now being denuded by marine currents, might well yield
us such a variety of pebbles as we find upon the beach. But we
have not yet the materials ready to decide which of these theories is
the true account.

Specimens of the rocks, fossils, etc., above mentioned, may be seen
arranged in the Museum of the University College of Wales.

Nore.-—It will be observed that these Notes on the Geology of Aberystwyth
(originally intended for publication in a local guide-book) are very imperfect. Toa
great extent this is due to the scanty work that has yet been done in our neighbour-
hood, and we hope that very soon many of the points now doubtful—such, for

O. J. A. Meyer—Chloritic Marl and Upper Greensand. 547

instance, as the exact age of the Aberystwyth group and the origin of the beach
pebbles—will be clearly made out. As the work progresses, I hope to publish
elsewhere more detailed accounts, and to describe the fossils. But the imperfection
is the greater on account of the necessity which obliges me to write these pages
when absent from Wales and without materials at hand to help me.

IIll.—Norrs RESPECTING CHLoRITIC Mart an» Uprer GREENSAND.
By C. J. A. Mr¥er, F.G.S.

AVING paid but little attention to geological literature during
the last two years, it was not until September, 1878, that I
became aware of Mr. A. J. Jukes Browne’s article in the GroLoGicaL
Magazine of August, 1877.! In this article, amongst other matters,
the author criticises very fairly the classification of the Upper
Greensand and “Chloritic Marl,” so-called, as set forth in my paper
on the Cretaceous Rocks of Beer Head.* In justice to certain
questions involved, I find myself compelled to reply to this criticism,
and to say a few words besides respecting the Chloritic Marl and
Upper Greensand.

In my description of the Cretaceous Rocks of Beer Head—after
showing the great difference between the faunas of the highest and
lowest beds of what had been always previously classified as Upper
Greensand, and after proving that the one represented a Blackdown,
the other a Warminster fauna—I suggested that beds 10 to 12 of my
section therein given, on account of their special fauna, should be
separated from the Upper Greensand under the distinctive title of
Warminster Beds. I further pointed out that beds 10 to 12 re-
presented, both in fauna and position, the so-called ‘‘ Chloritic Marl”
of the Isle of Wight.

In suggesting the term Warminster Beds for my beds 10 to 12,
I ought at the time, indeed, to have explained that by such term
I meant that portion only of the Warminster strata from which, at
Chute Farm, near Warminster, so rich a fauna has been collected,
and which fauna has been always spoken of, erroneously as I think,
as coming from the Upper Greensand of Warminster. Jor the
actual “‘Upper Greensand” of Warminster, as every one knows,

is of considerable thickness. It consists in the lower part of sandy

marl, resting at Crockerton on Gault, and passing upwards, as in the
coast sections, into sands with Chert ;—the usual “Malm Series”
and “‘Chert Series,” in fact, of the Upper Greensand.

But none of these beds contain the noted “ Warminster fossils.”
These fossils are, and always have been, collected from the surface
of the field in which they once abounded, the rock which yields, or
yielded, them being unexposed. Portions of the matrix may be seen,
however, both outside and inside many of these fossils, and such
matrix has the appearance of Chloritic Marl, although the cement is
now siliceous instead of calcareous.

The “Chute Farm” fauna is then the Warminster fauna, as
generally known. It is also the fauna, in great measure, of my beds

1 Grou. Mac. Dee. II. Vol. IV. p. 350.
2 Quart. Journ. Geol. Soc. yol. xxx. p. 369.

548 C0. J. A. Meyer—Chloritic Marl and Upper Greensand.

10 to 12 of Beer Head, and of the so-called “Chloritic Marl” of
the Isle of Wight, and of Chardstock. Was I wrong then in
suggesting the separation of beds 10 to 12 from the Upper Greensand
and applying to them the term ‘ Warminster Beds” ??

Dr. C. Barrois, Mr. A. J. Jukes Browne,’ and probably many
other geologists, consider that I was wrong. Because, say they, the
fauna of beds 10 to 12 is found also in the Upper Greensand. But
where? Not at Beer Head. And, with the exception of Pecten
asper and one or two other wide-ranging fossils, not at Warminster.
Nor yet, in reality, in the Isle of Wight. Barrois, quoting from
older lists, gives indeed a number of species as coming from the
Chert Beds at Warminster,* and others as from the Upper Greensand
of the Isle of Wight. The greater part of these however came,
probably, on his own showing, from the base of the “ Chloritic
Marl” of Ibbetson. To prove this I also, following Mr. Jukes
Browne’s example, must say a word or two respecting that much-
abused term, ‘‘ Chloritic Marl.”

Now Mr. Jukes Browne,® in his otherwise careful and valuable
résumé on the origin and application of the term “ Chloritic Marl,”
has failed, apparently, to notice one point of considerable importance
in respect to it, and one from which in fact has arisen very much of
the difference in thought and practice regarding the application of
the term. And it is this :—That under the term “ Chloritic Marl,”
Captain Ibbetson (in 1849) would seem to have included two beds of
very similar composition; both loaded with green grains, both
phosphatic. Beds which although in actual contact were certainly
in age widely separated. Captain Ibbetson’s “Chloritic Marl”
embraced in fact the (local) top of the Upper Greensand, and the
(local) bottom of the Chalk Marl of the Isle of Wight.

For “The Chloritic Marl,” says Captain Ibbetson,’ “ divides the
Chalk Marl from the Upper Greensand. It is a grey marl full of
green grains of a silicate of iron and sand, very fossiliferous. The
upper part in places exhibits a conglomerate of pebbles and small
boulders, and in it the fossils are chiefly broken as if rolled on a
beach.”

Now, all who have examined the junction-beds of the Upper
Greensand and Chalk Marl near St. Catharine’s Down, in the Isle
of Wight, will see the significance of the above description. The
“‘congiomerate of pebbles and small boulders” occurs on the actual
line of division of two faunas. The lower of which includes Pecten
asper, Terebratella pectita, Catopygus columbarius, Galerites castanea
and various other Echinoderms; the upper, Ammonites, Scaphites,
Turrilites, etc., mostly phosphatic. It might, perhaps, be objected that

1 Quart. Journ. Geol. Soc. vol. xxx. p. 371.

2 Grou. Mac. Dee. II. Vol. IV. p. 388.

3 Recherches sur la Terrain Crétacé sup. de l’ Angleterre, par Ch. Barrois, D.Sc.,
Lille, 1876, p. 58.

4 1/Age des Couches de Blackdown, par. Ch. Barrois, D.Sc., An. Soc. Geol. du
Nord, tom. iil. p 4.

5 Grou. Mae. Dee. IT. Vol. IV. p. 356.

6 Notes, etc., on the Strata of the Isle of Wight, London, 1849.

O. J. A. Meyer —Chloritic Marl and Upper Greensand. 549

the term “Chloritic Marl” has been always subsequently applied to
the upper of these two beds—the ‘“Scaphites-bed”’ or actual base-bed
of the Chalk Marl. Such, however, is not the case. In Mem. Geol.
Survey, Dec. iii. page 4, Professor Forbes, referring to Chloritic
Marl, says:—“It is a remarkable stratum abounding in peculiar
fossils, and containing numerous Hechinoderms. I have examined it
and found the small variety of Galerites castanea plentifully near
the village of Chaldon, in Dorsetshire.” “Both larger and smaller
varieties occur near Warminster.” Now the small variety of Galer-
ites castanea, in the Isle of Wight, belongs especially to the lower
half of the Chloritic Marl of Ibbetson.

It appears, therefore, that the term ‘Chloritic Marl” as first
applied embraced two sets of strata with, in time at least, a gap
between them.

In the light of recent researches this fact has become more evident
than it could possibly have been in former times. One knows now
that the Cretaceous rocks do not exhibit in any one locality a perfect
series. Here and there some bed is wanting—rarely indeed without
some sign or indication of the fact. Pebble-beds, grit-beds, layers of
phosphatic nodules, lines of erosion, and sudden changes of fauna, all
point usually to missing strata. And in no part of the Cretaceous
rocks is this, perhaps, more frequently evident than between the
Upper Gault and the Chalk with Inoceramus labiatus. To illustrate
this one need but follow the, already, partly recognized life-zones of
the intermediate strata. For, thanks to Hébert, Barrois, and other
diligent observers, it is now well-nigh established that beneath the
Chalk with Inoceramus labiatus one finds, or ought to find, the
following life-zones :—

g. Zone of Belemnites plenus.

» Holaster subglobosus.

» Scaphites equalis=The zone of Ammonites laticlavius, of Barrois.

», LHolaster nodulosus (of Hébert).

Trigonia sulcataria.

», Ostrea vesiculosa, and Janira quadricostata

», Lxogyra conica and Cardiaster fossarius=The zone of Ammonites in-
Jfiatus (in part), of Barrois.

But, at Folkestone, zones a. 6. c. d. are missing. At Cambridge

a. b. c. d. and e. are missing. While near Beer Head g. in places

rests on d. And, probably, because the bases of zones d. e. f. g.

contain green grains and remanie phosphatic fossils in some localities,

the term ‘“Chloritic Marl” has been at various times applied to each

and all. Nor is this surprising. For one finds that in France and

Belgium the, to some extent, equivalent terms “'Tourtia” and

‘Marne Glauconieuse” have been also not infrequently applied to

beds of various ages.

That the term ‘“Chloritic Marl” is then, and has always been, a
bad one, is clear enough, Yet this in no way affects the correctness
of my reference of beds 10 to 12 of the Devon sections to Chloritic
Marl.!' These beds embrace the Chloritic Marl of the Isle of Wight
and more besides. The phosphatic fossils in bed 13 of Beer Head

=The zone of Pecten asper, of
Barrois.

Ree arsh

1 Quart. Journ. Geol. Soc. vol. xxx. p. 385.

000 C.J. A. Meyer—Chiloritic Marl and Upper Greensand.

(referred by Barrois to Chloritic Marl)! are entirely remanie of older
beds. Bed 13 itself is of the zone of Belemnites plenus, and is
followed immediately by the zone of Inoceramus labiatus. Recent
investigation has proved to me that I was wrong therefore in giving
to Holaster subglobosus so wide a range in my tables of fossils.? In
the vicinity of Beer Head Holaster subglobosus occurs in places in
bed 12. Rarely between beds 12 and 18.

Or, in the Beer Head and Branscombe cliffs :—

Beds 16, 15, 14=The zone of Inoceramus labiatus.
Bed 13 =The zone of Belemnites plenus.
Beds 12, 11, 10 =Condensed life-zones apparently of :
Holaster subglobosus.
Scaphites equalis.
Holaster nodulosus.
Trigonia sulcataria.

Now the Upper Greensand (typical) of the Isle of Wight—both
Chert Series and Malm Series—is fully represented in the Devon
cliffs by my beds 6, 5, 4, 3. Beds 8 and 9 not being present in the
Isle of Wight. To separate beds 10, 11, 12 from the Upper Green-
sand of the Devon cliffs does not, therefore, in any way diminish the
original range of the Upper Greensand, as Mr. Jukes Browne
apparently supposes.®

Moreover, my beds 8 and 9 with Orbitolites concava, and bed 10
with Trigonia sulcataria, Codiopsis doma, etc., represent respectively
the “ Craie de Rouen” and “Gres du Maine,” in part, of Prot.
Hébert.* And these beds, though widely developed in France, seem
absolutely unrepresented in the Isle of Wight. And, inasmuch as
the position of beds 8 and 9 is actually between the Chert Beds of
the Isle of Wight and the base of the Chloritic Marl of Ibbetson,
there is in this again a further reason for distinguishing my
Warminster beds (10, 11, 12) from the Malm Series and Chert
Series of the Upper Greensand. For these and other reasons I
cannot agree with Dr. C. Barrois and Mr. A. J. Jukes Browne in
classifying beds 10, 11, 12 with the Upper Greensand.

Neither should English geologists too hastily agree with Dr.
Barrois’ definition of the Upper Greensand as found in England.°
The fauna of our Upper Greensand is a poor one undoubtedly.
And it is true enough (as Dr. Barrois says) that the fauna of the
Malm Series of the Upper Greensand approaches to that of Black-
down, and the fauna of the Chert Series to that of Warminster.
But it is not, therefore, necessary to divide the Upper Greensand.
The English Upper Greensand fauna has never been worked out
carefully. When this has been done it will be found probably to
approach more nearly, as a whole, to that of the ‘‘Meule de
Bracquegnies”” than separately to the faunas of Blackdown and

1 Recherches sur le Ter. Crét. de ]’Angleterre, Lille, 1876, page 71.

2 Quart. Journ. Geol. Soc. vol. xxx. p. 386.

3 Grou. Mae. Dec. II. Vol. IV. p. 387.

£ Bull. Soc. Geol. de France, 2° ser. vol. xx.

5 L’ Age des Couches de Blackdown, par Ch. Barrois, An. Soc. Geol. du Nord,
tom. 1. p. 1.

O. Fisher—On Possible Changes of Latitude. 5d1

Warminster. For the fossils of the “ Meule de Bracquegnies,” so
many of which have been referred by MM. Cornet and Briart to
Blackdown species,’ appear to me to form rather the passage fauna
between the (in England) totally distinct faunas of Blackdown and
Warminster.

While thus maintaining the correctness of correlating beds 10 to
12 and the Warminster beds of Chute Farm with the Chloritic Marl
of Ibbetson, and of distinguishing all alike from the Upper Green-
sand, I ought at the same time to admit that such an arrangement
still leaves much to be more fully determined. Beds 10 to 12 and
the Warminster beds will still, to some extent, represent an un-
known quantity, inasmuch as they themselves include beds of
various ages, partly remanie, and which are probably elsewhere very
differently represented. Judged by their fauna they include certainly
two, if not three, divisions of the French and Belgian ‘ Tourtias,”
as defined by MM. Dumont, Cornet and Briart, Hébert, Gosselet,
Barrois,—and in part also the “Griinsand (Tourtia) von Hssen.”
Fragmentary beds all of them, existing often only as outliers, and
the exact correlation of which even Barrois? finds yet difficult to
determine.

IV.—On tue Possrpiniry or CHANGES IN THE LATITUDES oF PLacEs
ON THE HartH’s SurFace; BEING A Repty to Mr. Hittz’s
LETTER.

By O. Fisuer, Clk., M.A., F.G.S. é

AM grateful to Mr. Hill for noticing my former paper “On
Possible Changes of Latitude on the Earth’s Surface” in his
letter, October, 1878, p. 479. I wish, however, that he had gone into
the subject more in detail ; in which case I, and perhaps others, would
have felt more satisfied with his reply. He epitomizes my appeal to
physicists by making me ask, “ Assuming that a thin crust surrounds

a fluid substratum, could then a deformation shift the crust over

the nucleus?” And he replies that, Mr. G. Darwin having proved

that the earth is “‘enormously stiff,” the discussion would be fruitless,

But in this statement of my question and reply to it, he has omitted

what seems to me the important proviso, based on Hopkins’ reason-

ing about the mode of cooling, that this fluid substratum is shallow,
and encloses a rigid nucleus; and given no reply to my inquiry
whether such a supposition might not afford the required rigidity.
Again, referring to the recent disproof of Hopkins’ demonstration
of rigidity drawn from the amount of precession, Mr. Hill argues
that, since the fluid nucleus being spheroidal and rotating would
resist the tilting force which produces precession, and the shell
would not slide freely, “ would it not also resist the tilting tendency
resulting from a deformation?”’ I am not quite certain that I under-
stand this. If Mr. Hill means that the rotation would compel the
fluid substratum to retain its spheroidal form, so that a rigid crust
1 Briart et Cornet, Mémoires de |’ Académie R. de Belgique, tom. xxxiv.

2 Mem. sur le Terrain Orétacé des Ardennes, etc., par Chas. Barrois, D.Sc.,
Lille, 1878, p. 346.

502 J. F. Walker—Terebratula Moriéri in England.

could not slide over it, I grant that there would be truth in the
objection. But if the crust be considered flexible, as practically it
must be if of small thickness and liable to corrugation, then I do not
see why the rotation of the fluid should have the effect of preventing
the crust slipping over the nucleus, and adapting itself to such a
position of equilibrium, as any irregularities of thickness resulting
from corrugation might render necessary under the action of the
centrifugal force and gravitation.

The final query put by Mr. Hill is this— Will a change in
latitudes give the best explanation of the phenomena?” To this I
reply, that we have four chief classes of facts to account for :

1. The almost ubiquitous presence, either in present or past times,

of volcanic action ; apparently showing that wherever the earth’s
___ surface is pierced to a sufficient depth, a molten stratum is tapped.
2. The capacity for slipping towards certain lines which the crust
possesses, as proved by the lateral compression of the strata
along the flanks of mountain chains.

3. The amount of horizontal compression of the superficial strata

being greater than the cooling of a solid earth can account for.

4, Changes of climate—notably the existence of a warm climate

in former times near the North Pole.

These are the phenomena, and it appears to me that these four
classes of facts point convergently towards the doctrine of a fluid
substratum. It is quite true that the question which I put to physicists
and now repeat was whether a fluid substratum over a rigid nucleus
would not be compatible with mechanical considerations, and whether.
under those circumstances changes in latitude would not result from un-
equal thickening of the crust? And I suggested that the present
distribution of the continents gives support to that idea. But I
was not seeking primarily to account for changes of climate in that
manner. hat theory belongs to Dr. Evans; and he has ably
defended it against Dr. Haughton’s somewhat formidable objections
in his recent address to the British Association at Dublin. The sup-
position alternative to Dr. Evans’, by which Dr. Haughton would
account for a former warm climate at the Pole through residual heat
in the earth, has, I think, been disposed of by anticipation in Sir W.
Thomson’s paper on the Secular Cooling.

V.—On THE Occurrence or Trerepratuta Morrert 1x ENGLAND.
By Joun Francis WALKER, M.A., F.G.S., ete.
VALUABLE paper by T. Davidson, Esq., F.R.S., appeared in
the Proceedings of the Dorset Natural History and Antiquarian
Field Club for 1877, ‘On the species of Brachiopoda that occur in
the Inferior Oolite at Bradford Abbas and its vicinity.” Since then,
during a recent visit to this locality, I have added a few species to
this list, including two which have not been discovered in England
before. I propose to give a short account of these species, and also
a table showing the relative distribution of the Brachiopoda in the
Inferior Oolite and Fuller’s Earth deposits at Cheltenham and
France, compared with this district.

J. F. Waiker—Terebratula Moriéri in England. 553

’ The most important discovery is that of the well-marked species
Terebratula Moriéri, which has hitherto only been found in France.
It was first described and figured by Mr. Davidson in the Annals of
Natural History for 1852, vol. ix. (second series) p. 256, pl. xiv. fig. 3
and a, b,—the MS. name of Terebratula Moriéri having been given
to it by Deslongchamps after its discoverer M. Moriére. It was
afterwards described and figured by E. Deslongchamps in 1857,
“Catalogue descriptif des Brachiopodes du systéme Oolitique Inférieur
du Calvados,” p. 37, pl. iv. fig. 6, a, b; and in 1877, in the Paléon-
tologie Francaise Terrain Jurassique, Brachiopodes, p. 244, pl. xv.
figs. 1-8. It is a very rare species, having been found in France in
only one locality, Ste. Honorine des Perthes (Calvados), in the white
Oolite of Port-en-Bessin, which contains Terebratula Phillipsit,
Morris, and Rhynchonella plicatella, Sow. ; these species occur with it
in England.

There appears to have been some doubt whether in France this
species had been found in position, or in a loose block which might
have fallen from the Great Oolite above. M. Deslongchamps
regarded it as an Inferior Oolite fossil, but the finding of this
species settles the question with regard to its age, as no Great Oolite
occurs in the quarry from which I obtained this specimen.

Whilst examining the well-known quarry at Bradford Abbas, on
the farm of Prof. Buckman, I picked up this specimen from the
horizon of Rhynchonella parvula, H. Desl., but did not recognize it
until I commenced to clean it; it corresponds in all respects with
the figured specimens, showing the deep sinus in both valves and
the peculiar concentric projecting imbricated ridges which well
distinguish this species. It belongs to a small group, of which it is
the earliest representative, followed, in the Fuller’s Harth rock, by
Terebratula reticulata and the closely-allied or identical species
Terebratula hybrida, and in the Great Oolite by Terebratula coarctata.
The specimen is about the size of figure 7 in pl. 65, Pal. Frang.
Brachiopodes Jurassique. It is well preserved, both valves being
perfect. I also obtained from the quarries at Half Way House a
specimen of Rhynchonella subdecorata, and one or two specimens of
Ehyn. ringens unusually large for English specimens. Also three
specimens of a Waldheimia which appears to be Waldheimia sub-
bucculenta, Chap. et Dew., and probably the same as the species
figured, but not named, by Mr. Davidson in his paper on the Dorset
Brachiopoda, pl. iii. figs. 14-15. Waldheimia subbucculenta is stated
to occur in France in the lower part of the Fuller’s Harth, but
probably what in England would be called the upper part of the
Inferior Oolite. It is a species which is closely allied to W. Waltoni,
Dav., and somewhat resembles W. indentata and W. perforata of the
Lias; W. humeralis of the Kimmeridge; and pseudojurensis of the Neo-
comian. It is a long, narrow, flat shell, tapering towards the beak
and front margin, foramen small, beak ridges well defined, and a dark
line on the smaller valve indicates the presence of a septum, showing
that the loop was long. It will be figured with the other species in
the appendix to-Mr. Davidson’s supplement to his great work on
Jurassic Brachiopoda.

504 J. F. Walker—Terebratula Moriéri in England.

List or BRACHIOPODA FOUND IN THE INFERIOR OoLITE AND FULLER'S EARTH.

SOMERSET Gummi

. AND
Explanations.—r =rare, s=scarce, c=common, moncen

HAM,

FRANCE.

* other localities only.

I,0.| F.E.] 1.0.

*Lingula Beanii, Phillips (Yorkshire) .....cssseecsssee| sso
*Discina reflewa, Sow. (YOrKSDIve) — ssssssssssssssseeesesseseesees| sone
Dundriensis, Dav. (DUndry) wesc r
Etheridgii, Dav. (Nailsorshh RE aac,
Crania Saundersi, Moore (Dundry).......ecssessseeeesn r
canalis, Moore (Dundry) .u...ssssseecccceeceeeee Yr
Spiriferina ? Oolitica, Moore (Dundry) uu... r
minuta, Moore (Dundry) ......ccescsscseesen c
Theeidium Bouchardi, Dav. (DUndry) ...r-ssseessssuseeee r
Dickensoni, Moore (Dinnington) ............... r
truangulame el Or Dapeee ree c
duplicatum, Moore (Dundry) ovss..-s-sseseeeee r
serratum, Moore (Dundry) ....sssssseeecccccereee r
Forbesti, Moore (Dundry).....eseeseccccccseseseee r
septatum, Moore (Dundry) -eeeecseeccesseeeseee r
granulosum, Moore (Dundry) ....- r
Argiope? Oolitica, Dav. (DUMdry) cesses r
Zellania Davidsoni, Moore (DUnArY) ......csscccesescsseee c
Laboucheri, Moore (Dundry) oe r
globata, Moore WON (veh Gi a Selle
Oolitica, Moore, (Dumdry) reeves r
Terebratulina Dundri iensis, Dav. (DUNATY) cscs r
Terebratula submasillata, MOYTIAS ...sccccscscssssecsssescssessee| see
EROUAIUS A SOW eo errr eee c
var. ampla, BUCKMAN. ......cssssssessee csnsneeeeseee s
var. Ailetnit, Wamarle o.ccccccccscsssssscssssscossecrsese| cece
Phillips eMOrrisipeseere ee ¢
var. Phillipsiand, Walker ....csssssssccssccsssessee| cece
VENEVUCOSG, LVCTCD cessecseescsssecssnessere son sees Serna latest
BUCK MAUS aNegee ee Tr
var. Buckmaniana, Walker ..cecccsecceen| see
* trilineata, Y. and B. (Yorkshire) .....0.0.000..) s+
Haresfieldensis, Dav. scrrsccccccsssssssccesssessssne| ssces
SMT OUAGLUS, SOW cccoecccectecreccceseeceescerecssseeersssser c
GlODALA, SOWe ccetecccceessscrseeccrcseee Les
var. Birdlipensis, Walker ..eccsssscccsssssscssseecees| couse
pHiceschenin Oppe emeeeceerer reser ieee
Hu dest OM Pe messes seen eee c
Cong lob itch) Ose creee. eects ers P
Ferryi, KE. Desl. a... 208
THYNT ATE Oy IDEN IS | comcecorenemeercereenecceee|| (Cea
Wrightit, Dav. cee Dae ee
SUT Mia XU MGNEN eer odnmerteceerecioceeene || co
PORCH, UIUC —eprccconceememercenomoeeee|| occ
SUMO TUE LS OW aecetect ete Oo sactoe ac cotta | eee
galeiformis, M‘Coy, MS. (near Minchin-| .....
hampton).....) .....
eS Sow. (Whatley, Heoree) nasties ated
TREICLO RI Deg ND YOTSIS eet rteere ere tereteecentse [toy
tnfra=Oolitica, Ei. Desh. ii cscsosscccsseen|| cree
Stephant, Dav. ...cssses
decipiens, K. Desl. ...
Crant@, Dave crccccssrrsseiss

Whitakert, Walker

eens

cane

eeeee

pene

eenee

sone

Poors

eneee

Prerry

sense

eeeee

eenee

aren

ovnse

oonee

Cores

J. F. Walker—Terebratula Moriéri in England.

555

List or BRAcHIOPODA—continued.

Terebratula provincialis, EK. Desh. sssssssssseeesssesneen
curvifrons, Oppel
Mor veri, Davari
eurviconcha, Oppel
Fylgia, Oppel
* Wurttenbergica, Oppel (Germany)
“ omalogastyr, Hehl Ziet. (Germany)
Waldheimia emarginata, Sow.
Waltoni, Dav.
subbucculenta, Chap. et Dew. .....
ornithocephala, SOW. sss
Cadomensis, B. Desl.
Hughesii, Walker
carinata, Lamarck
var. Mandelslohi, Oppel = W. carinata—
alveata, Quensted
var. Blakei, Walker (Yorkshire)
Meriana, Oppel
Dreckenbyt, Walker .......cccsssssssssssssccersnsneseeee
cardium, var. Leckhamptonensis, Walker
Anglica, Oppel
bullata, SOW. «2... :
Megerlia Munieri, BE. Desh. ....sssssssssssssssessssessuniie
Terebratella bivallata, Ki. Desl._....
sulcifrons, Benecke
Rhynchonella frontalis, E. Desl. _...
VAPOR, IDEN coxcccccectcceremoroonn ac
plicatella, SOW. srr.

sescaseuesecesees

weneeccececcanccecapausccsessceucsscscssasesseessnaeete

subtetrahedra, Dav.
subdecorata, Dave...
quadruplicata, Zieten

*

*
*

UCR IDEN IS ccocoreceereeccen sere tether eenp cern
cynocephala, Richard ........sessssesceccessseeessssesee
ringens, Herault
subringens, Dav. .....
Oolitica, Dav...
Forbesii, Dav.
SUDODSOlEtA, DAV. — -sscsssssessssersssessesersecsssesseeerseense
angulata, SOW. vs
subangulata, Dav.
Smithii, Walker

PArVULA, HW. Desh. cccccsccsreccscrecscsssseeccrssececrsvsosess
Stephani, Dav. .....
ODOUR IKON ecoccescecocceocnneto ean cee
Crossii, Walker (Lincolnsh. & Yorksh.)
SOIGIEOS Ey Wo UBXUONS —_ cerenceeccercovocnmecnucerenoccocxe
acuticosta, Hehl Zieten (Germany)
Stiufensis, Oppel (Germany)

SOMERSET Geminis

!
FRANCE. |

Doe ewe
1.0. | F.E.] 1 O. | F.E [ 1.0. | F.E.
@ecce | essce ff coocn | c8889 Cc eecee |
ral (Mees reread eerPen (ie eng (error
Te Ai) eescoe | ecco ecers a lin |
TSU EE 2 ale oa r |
oh cop|) 8 0G Ee i ee ee ce
TAN |e beloy [eseee c ec
Spores poe Mae CPs
Be Wa Peecpeg ail|b iceceo c Cc
pe Ce colin ele ealiae
oecen iS} ome Tr Cc fH
coco. || toes it enn coon reece |}
Cet eae rel ieee on hee |
s Creole: c Cc |
com | ocr 1) esece ] cea | eon {] cxcce |
Chelios Gulp: Co ee |
el eae TY, eet a ae
Taos need erent Kopre aa fs nen |
re ie Re ean Pe: Jat
ioe c ees leroy | (ete esky «
BPMN oc Might llgees ORP oees r
see | \ieasertell Ketan be cecal Freee ce |
PE eee ee El ae Bee c
Sh RE Meee | aces r hae
Beene | tenes © | co || © ae
(Caen eel eee CL ase
(8 ills fee cuwlees (Hall barked
Bet Esk in| ees Py? ||
Sel eee eee frecsal (Gay tae
ee pee (EVE eee etre | steeen,
Se aes CG. Gree. r
(Cie ince) laid Lae Ch ieee
De eee! Need a een Wut || Se
ay All vere Chelle el ee
Ciel Sash eke esa eee
Nasi Wee (oman Peron | aeons
Frill lt oon Gi Chas naees
las GAs 25 | eee [ees
Cede alee ?
So ce s a (eee ser:
Sie tGh oh eee Cy as
pm eran eet oneal leer || hea:
Cc r Ce lies Chae
Tee Oe 87 Mea No (eal Dae

In a quarry near the church at Misterton, near Crewkerne, I found
a band of clay lying on the top of the Inferior Oolite stone, con-
taining numerous specimens of a variety of Waldheimia Meriana

associated with T. decipiens.

It is probable that some of the

556 - Dr. H. Woodward—On Meyeria Wiillettir.

specimens found in this district, referred to T. Eudesii, Oppel, may
belong to Terebratula conglobata, Desl. |

I have thought it necessary, in drawing up the preceding table, to
give the species found in the Fuller’s Earth as well as those found
in the Inferior Oolite, as these beds are closely connected, and the
division may have been drawn differently in France and in England.

Remarks.—The specimens which occur at Dundry are identical
with those in the Sherborne district; but the small shells Thecidea,
Zellania, etc., have not yet been found in the latter locality, but will
be sought for the next time Prof. Buckman’s quarry is worked for
road-metal. Several Thecidea, etc., and more Rhynchonelle may occur
in France, but as these have not yet been described in the Paléon-
tologie Francaise, the list may be incomplete. Terebratula maaillata
and Rhynchonella concinna have been stated to occur in the Fuller’s
Earth of Sapperton Tunnel near Cirencester, but a blue band of the
Great Oolite was cut through in making the tunnel, and the fossils
from it were mixed with those from the Fuller’s Earth, being nearly
the same colour. It will be observed that the species peculiar to
the Oolitic Marl of Cheltenham district, as Rhyn. Lycetti, Day., Rhyn.
subobsoleta, Dav., Waldheimia Leckenbyi, Walker, Terebratula fim-
bria, Sow., Terebratula submazillata, Dav., etc., are wanting both in
the Dorset district and in France; and that several species, as Rh.
ringens, Herault, Rh. parvula, H. Desl., Rh. plicatella, Sow., Rh. senti-
cosa, v. Buch, Waldheimia subbucculenta, Chap. et Dew., W. Waltoni,
Dav., W. emarginata, Sow., Terebratula decipiens, EK. Desl., T. Ferryi,
KE. Desl., T. Woriéri, Desl. and Dav., T. Stephani, Dav., T. spheroid-
alis, Sow., occur in France and Dorset and Somerset, and not at
Cheltenham. Probably some Paleozoic barrier separated these two
areas during the deposit of these zones, and the exact equivalents
may not be able to be found on comparing the different horizons of
the Inferior Oolite of these districts. The Oolite marl being absent
in France and Dorset; the bed containing Rh. ringens has not been
found at Cheltenham. It is also worthy of remark that the Brachi-
opoda of the other Oolitic strata, and the Lias of Somerset and
Dorset contain several species which do not occur in other parts of
England, but are common in France.

VI.—On Meverra Witrerri, « New Macrovrovus OrustTAackaNn
FROM THE CHALK OF SussEXx.!

By Henry Woopwarp, LL.D., F.R.S., F.G.S.,
of the British Museum.

HE genus Meyeria was established by Prof. M‘Coy, in 1849, for
the reception of certain Crustaceans from the Gault and Green-
sand, found at Speeton, Yorkshire, and at Atherfield, in the Isle of
Wight. A new form has been most obligingly sent to me for
examination by Henry Willett, Esq., F.G.S.; and this being in
a more perfect state of preservation than any heretofore obtained,

! Originally published in Dixon and Jones’ Geology of Sussex, 1878, p. 379.

Dr. H. Woodward—On Meyeria Willettii. 557

enables me to refer to the same species about eight other remains
from the Chalk preserved in the British Museum and including the
carapace figured on pl. xxxviii. fig. 8 of Dixon’s Geology of Sussex.

M‘Coy considered Meyeria to belong to the family Thalassinade:
but to this Prof. Bell demurs, considering it ought to be associated
with the Astacid@, the division across the exterior plate of the tail
being an absolutely distinctive character of the latter family.

It will be observed that Mr. Willett’s specimen, figured in the
annexed woodcut, agrees more nearly in size with Meyeria ornata,

Meyeria Willettii, H. Woodw. White Chalk, Lewes. Natural size.

from Speeton, than with the much larger species, Meyeria vectensis,
from Atherfield. The abdominal somites of our specimen, however,
are not ornamented, as in M. ornata, with four or five transverse
elevated rows of rounded granulations, but are nearly plain, as in
M. vectensis, save that each segment is marked by two lateral grooves
enclosing a somewhat raised area, and their epimera are granulated
and furnished with small spines along their border, which is trun-
cated. The median lobe of the tail is wanting, but two lateral lobes
are present, the outer of which is transversely divided along the
distal border. The carapace is evenly and finely granulated; the
cervical furrow is nearly straight, dividing the carapace at about one
third of its length from the front; the cardiac furrow is clearly
marked, enclosing a broadly triangular area, the sides of which slope
upwards on either hand from the cervical furrow, and meet upon the
dorsal line near the posterior margin of the carapace.

Three nearly parallel ridges, with slightly more prominent
granules, mark the gastric region of the carapace. A furrow,
uniting with the cervical and cardiac furrows, curves around the
hepatic region, and separates it from the other regions of the
carapace. This part is very indistinct in Mr. Willett’s specimen,
but is well shown in the carapace figured by Dixon.

From Mr. Willett’s specimen, and still more clearly marked in
one of Dr. Mantell’s, we learn that the forearms were long, slender,

558 Prof. E. W. Claypole—Fossil Tree from the U. Silurian.

and bordered by small spines, the surface granulated, and the
extremities monodactylous.

The four pairs of feet were long and slender, their surfaces smooth
(not granulated like the forearms), and their edges bordered by
small spines. Of the antennz we cannot speak, as they have not
been preserved.

The specimen figured in the accompanying woodcut! is from the
White Chalk of Lewes, and probably Dr. Mantell’s and Mr. Dixon’s
specimens are from the same locality. There is also a closely
allied, if not identical, species preserved in the British Museum,
from the Upper Greensand of Wiltshire (part of Mr. W. Cunnington’s
Collection), and another from near Ventnor (Chalk-rock ?), presented
by Prof. T. Rupert Jones, F.R.S.

I dedicate this species to H. Willett, Esq., F.G.S., whose exertions
on behalf of the Sub-Wealden Boring, the completion of the
palzontology of the Chalk, and the success of the Brighton Museum,
are well known to all geologists.

VII.—Ow tHE Occurrence or a Fosstr Tren (GLuyPTODENDRON)
IN THE Curnron Limestone (BASE OF Upper SrturiaN), oF
Ouro, U.S.

By Professor EK. W. Cuaypoue, B.A., B.Sc. (London) ;
of Antioch College, Yellow Springs, Ohio.

URING the summer of 1877 I made a geological excursion, in
company with one of my students, to the western part of our
State, to examine the junction of the Upper Silurian (‘Clinton ” of
the Ohio Survey) and the Cincinnati group of the Lower Silurian.
Whilst thus engaged near Haton, in Preble Co., my companion,
Mr. Leven Siler, of that town, picked up and handed to me a slab
bearing what appeared to be a mould of the well-known bark of the
Lepidodendron, somewhat weathered. More careful examination
confirmed the first impression, and convinced me that I had in-
disputable proof of the existence of arborescent vegetation of an
earlier date than had hitherto been announced upon equally con-
clusive evidence.

The fossil, of which a woodcut accompanies this paper, is on
the surface of a slab of marine limestone. It measures about two
inches and a half, by two inches, and contains nearly fifty more
or less distinct scars, such as mark the bark of a Lepidodendron.
Its surface is cylindrically concave, and has just such an impression
as a round stem would produce—that is, it represents a segment of
a cylindrical surface, of the dimensions given above, and depressed
about half an inch in the middle. The squeeze accurately shows
both the marks and the curvature of the surface.

The slab containing it was not taken out of the solid rock, but
picked up loose on the surface of a bank close to the junction of the

1 For permission to use this illustration from Dixon’s Geology of Sussex (New
Edition, 1878) we are indebted to the kindness of the publisher, Mr. W. J. Smith of
Brighton.

Prof. E. W. Claypole—Fossil Tree from the U. Silurian. 559

Upper and Lower Silurian beds, which are here in juxtaposition and
conformable, though marked at their junction by a great palzonto-
logical break. It becomes therefore necessary to set forth the
evidence for its asserted age.

A
ue

muy
By
Rare

i) Rais
EN
~~

Ria
x He
i

Bui
ANT
ih i IN}
can nit
ei

iN}
Kt

De
Nt Ng

The oldest known yptodendron Eatonense, U. Silurian (Clinton), Eaton,

In the first place the general appearance of the stone is sufficient
to satisfy any one practically familiar with the locality that it belongs
to the horizon above mentioned. It is a slab of yellow, coarse-
grained, Encrinital limestone, considerably weathered, exactly like
the limestone of that date at Haton, and generally on the outcrop
around the Cincinnati exposure. In the second place, it contains on
its face one of the commonest of the Corals found in the “ Clinton ”
of the Ohio Survey, and closely resembling, if not identical with,
Cheetetes lycoperdon (Hall), from the Hudson River and Clinton
groups in New York, and figured in the first and second volumes
of the Report of the New York Survey. Thirdly, from the
back of the stone I chipped out a piece containing a small Illcenus,
the young of Illenus Daytonensis (Hall and Whitfield), Clinton
group, “Ohio Paleontology,” vol. ii.; or possibly of I. Varriensis
(Mur.), Z. cowus (Hall). As the last-mentioned genus is not recog-
nized above the Niagara (Wenlock) Group, this specimen is suffi-
cient to determine the age of the stone, and therefore of its contained
fossil."

At the outset of my examination, I was inclined to place the fossil
in the genus Lepidodendron; but further study has convinced me
that it cannot rightly be referred to that plant, and I therefore put it
by itself in a new genus, thus defined :—

GuypropenDRoN. ‘Tree-like stem cylindrical ; surface marked
with two parallel sets of ridges running spirally up the stem in
opposite directions, crossing each other and thus forming rhomboidal

1 The fossil was exhibited, and an address given upon it, at a meeting of the
Natural History Society of Cincinnati on January 1, 1878. Many gentlemen well

acquainted with the geology of this region were there present, and the evidence then

and there submitted was unanimously considered conclusive on the age and relations
of the fossil.— HE. W. C.

560 Prof. E. W. Claypole—Fossil Tree from the U. Silurian.

areoles. Lower portion of each areole depressed and probably

representing, or containing, a leaf-scar. Depressed portion of

areole (leaf-scar?) symmetrical (i.e. alike on right and left sides).

Vascular scars, leaves, fruit, ete., unknown. Ety. yAvda, I engrave;

from the depressed areoles.

I append the following specific description :—

GLYPTODENDRON Hatonrense. Stem thick and trunk-like, the
specimen described measured, when complete, about six inches in
diameter. Surface divided into rhomboidal areoles by two sets of
narrow ridges, parallel and equidistant, running spirally up the
stem in opposite directions. These ridges cross each other nearly
at right angles. ‘The areoles thus formed measure about seven-
sixteenths of an inch along each diagonal. Lower portion of
areole deeply and evenly depressed, and probably representing
a sunken leaf-scar. Upper border of depressed portion rounded in
outline, and elevated, equalling in height the spiral ridges. ty.
Eaton, Preble Co., Ohio, near which town the specimen was found.

The only species of Lepidodendron and of Sigillaria yet described
from American rocks older than the Carboniferous are the following
in order of time :-—

Lepidodendron (Sigillaria) Vanuxemi, Goeppert, 1886; ‘Flora Silurisch.’”” Chemung
Group, New York. Figured in “ Geology of 3rd District of New York,”
p- 184; also in Dana’s ‘‘ Manual,” 1874, p. 277.

Sigillaria simplicitas, Vanuxem, 1842; “Geology of 8rd District of New York,”
p. 190. Catskill Group.

Lepidodendron (Sigillaria) Chemungense, Hall, 1843; ‘‘ Geology of 4th District,”
p- 275. Chemung Group.

Lepidodendron primecum, Rogers, 1858; ‘‘Geology of Pennsylvania,” p. 828.
Hamilton Group.

Lepidodendron Gaspianum, Dawson, Quart. Journ. Geol. Soc. 1859, vol. xv. p. 488,
Catskill Group. See also “ Acadian Geology,” 1868, p. 542; Rogers’s
“Geology of Pennsylvania,” p. 829, fig. 677; ‘Geology of 3rd District of
New York,” p. 157.

Sigillaria palpebra, Dawson, 1862; Quart. Journ. Geol. Soc. vol. xviii. p. 309.
Hamilton Group. ;

Lepidodendron corrugatum, Dawson, 1860; Quart. Journ. Geol. Soc. vol. xv. p. 68;
from Akron, Ohio, formerly referred to the Devonian, is now regarded as of
Lower Carboniferous age; Dawson’s “ Report on Fossil Plants of Canada,”
1871, p. 34.

The following table will show the relation of this new fossil to
those of the two genera, named above, previously known in
America :—(see table on next page).

In 1861 Dr. Dawson mentioned the occurrence of Psilophyton
princeps in the Gaspé Limestone of Lower Helderberg (Ludlow)
age in Canada; but, from that time, the writer is not aware of the
announcement of any discovery of like nature until 1877, when
Dr. Carl Reeninger, State-Geologist of Michigan, discovered some
specimens of land-plants in the Lower Helderberg Limestone of
Monroe County in that State. These specimens were sent for
determination to Mr. Leo Lesquereux, of Columbus, Ohio, who has
described them to the American Philosophical Society at Phila-
delphia as Psilophytum cornutum, Lesq., and Annularia Reeningeri,
Lesq. With these exceptions, no indisputable traces of land plants

Prof. E. W. Claypole—Fossil Tree from the U. Silurian. 561

LEPIDODENDRON. _ SIGILLARIA.
CARBONIFEROUS. 50 sp.! 60 sp.!
13 sp.

(( L. costatum, Lesq.

» corrugatum, Dawson.

», radioplicatum, Dawson.
», aculeatum, Stern.

», forulatum, Lesq.

, obscurum, Lesq.

bo

Sub- or Lower Carbon- z ane
ea a » Veltheimianum, Stern.

», scobiniforme, Meek.
5, tetragonum, Stern.®
», Sternbergi, L. & H.

4
| », diplostegioides, Lesq.
» turbinatum, Lesq.
lL », Worthenanum, Lesq.
Catskill » Gaspianum, Dawson S. simplicitas
Chemungense 4
Chemung : a Vanieens
Hla tones eae ee 9 primevum S. palpebra
Corniferous ..... ahi
(ONSEN? erect Gen ce | Oo
Lower Helderberg ..... _ .....
Onondas cee
INtagaralg ee ie Ws ate
Clintionve siete Glyptodendron Eatonense®
INLIGIC Dea yee 4 Ree a Ree
Oneida Conglomerate
Hudson River (Cincinnati)
Lower Silurian

have yet been announced from the American Silurian or older rocks,
in spite of their immense extent.

A specimen was, however, described by Lesquereux in 1874
(“ American Journal of Science,” January) as a land-plant allied to
Sigillaria. It was found near Lebanon, Ohio, about 35 miles north-—
east of Cincinnati, and was thought to show faint traces of spiral
marks, like those upon the stem of Lepidodendron or Sigillaria. Myr.
Lesquereux remarks of the specimens (for there were two species) :

«They were fragments of small stems or branches, one about two
inches thick, cylindrical, the whole substance transformed into soft
grey clay, the bark or outer surface only distinctly moulded into
clay, and marked by rhomboidal continuous (sic: contiguous ?)
enlarged bolsters, surrounding the stem in a spiral, bearing at the
middle a small oval or rhomboidal scar, less distinct, though well
recognizable, and presenting the character of stems of Sigillaria
Menardi, Br., or of Sigillaria Serli, Br.”

Professor Newberry, remarking in the August number of the

1 See Miller’s ‘‘ American Paleozoic Fossils.”’

2 §. Lorwayana, given in the above-quoted Catalogue as ‘‘ Lower Carboniferous,”
is from the Middle Carboniferous or Coal-measures of Cape Breton. See Dawson’s
Report, 1873.

5 This species is omitted in the above Catalogue, but see Dawson’s Report, 1873.

4 iS. Chemungensis, of the same Catalogue, is a synonym for L. Chemungense.

5 Placed in this column to save space. This position is not inconsistent with the
affinity of the species.

DECADE II.—VOL. VY.—NO. XII. 36

562 Prof. E. W. Claypole—Fossil Tree from the U. Silurian.

same Journal, on these specimens, says:—“They had been in my
possession some time before the publication of Mr. Lesquereux’s
notice, and I had examined them with some care, and had also made
careful drawings of them. As the result of my examination, I am
compelled to say that I fail to find either in the external character
or internal structure of these specimens any satisfactory evidence
that they represent land-plants—still less that they form species of
the genus Sigillaria.” ‘They are simply casts in earthy limestone,
without carbonaceous matter or any traces of woody tissue.”

Tn the “ Review of the Fossil Flora of North America,” 1876,
Mr. Lesquereux says :—“ A few cylindrical branches or impressions
of branches upon clay, bearing upon their surface rhomboidal scars,
disposed in spirals around the stem, like those of Lepidodendron,
were lately discovered in the Cincinnati group of the Middle
Silurian. As they were found associated in the same strata with
fragments of fucoids and deep-marine Molluscs, their relation was
considered as being rather with peculiar forms of Algze.”

But in the paper above mentioned, 1877, Mr. Lesquereux reasserts
the terrestrial nature of these specimens, and describes them under
the name of Protostigma sigillarioides. The genus is thus defined.
«This generic name is provisionally admitted for the description of
fragments of stems, whose relation to species of Sigillaria, etc., is
surmised from the rhomboidal form of their scars.” He adds, in
the introduction, that Professors Dana, Haton, and Verrill all agree
in referring the remains to land-plants. Where such distinguished
authorities, with the advantage of having seen the specimens, ex-
press such opposite opinions, the matter must be considered at least
doubtful.

Mr. Lesquereux also describes, in the same paper, two other
‘specimens from the Cincinnati group. The former of these he names
Sphenophyllum primevum, and the latter Psilophyton gracillimum.
The opinion of so eminent and experienced a palzobotanist is
entitled to the greatest respect, and the discovery of fossil land-
plants of Lower Silurian age im some parts of America is by no
means an improbable event. It is right, however, to observe that
the latter of these is a fossil long known to collectors in this part
of the country, and by them always considered to be identical with
Graptolithus abnormis, Hall, from the Quebec Group of Canada.
This alone will show how much uncertainty as yet attends the
identification of the fossil. In regard to both the species just named
serious difficulties also arise from a consideration of the physical
geology of the region at the time in question, against too ready a
conclusion in favour of their terrestrial origin, and especially against
the probability of their occurrence near Cincinnati. During the
existence of the Cincinnati Ocean of Lower Silurian date, the whole
of the interior basin was under water. The nearest shores were
the Blue Ridge of the Appalachian chain, on the east, 500 miles
from Cincinnati—the Laurentian highlands, on the north, at about
the same distance—the Huronian (?) highlands of Michigan, to the
north-west—the present site of the Rocky Mountains, to the west—

Prof. E. W. Claypole—Fossil Tree from the U. Silurian. 568

and the high grounds of Texas to the south-west—all at yet
greater distances. It is somewhat difficult to conceive of the pre-
servation of a filmy frond of Sphenophyllum during a voyage of so
great a distance, and its entombment in mid-ocean in a recognizable
condition. The same objections do not apply with equal force to
the preservation of a stem of a tree, if Protostigma was such, though
it may be doubted if any other case has come to light of the discovery
of undoubted fossil wood 500 miles from the nearest contempo-
raneous land.

In regard to the fossil described in the present paper, the case is
different. About the close of the Lower Silurian age an uplift
occurred along a line reaching from Ontario, in Canada, to Ten-
nessee—the forerunner apparently of that later movement which
elevated the Alleghany Mountains. This uplift was an area of dry
land during the interval which, in this region, elapsed between the
Lower and Upper Silurian formations. The return of the sea is
marked by a conglomerate of Lower Silurian pebbles in a matrix
of Clinton Limestone. “This proves that, before the deposition of
the Clinton, the Cincinnati group was consolidated into rock and
raised into cliffs and shore-lines, which were eaten away by the
waves at the ocean-level to form a pebbly beach.”—“ Geology of
Ohio,” vol. i. p. 103. On this Cincinnati Island of Upper Silurian
age there probably grew the tree of which a part produced the
impression above described and named. At the same time the
scarcity of such relics (no other having yet come to light), where
the land was at most but a few miles distant, brings out more
strongly the improbability of finding such remains in the Lower
Silurian rocks of the same locality, when the Island of Cincinnati
had not come into existence.

The Silurian Botany of Europe is equally scanty. The Lyco-
podiaceous spore-cases (Pachytheca, Hooker) from the Ludlow bone-
bed’ correspond, in date, with the plants from the Lower Helderberg
of Michigan. The Sagenarieg (Lepidodendra) of the Upper Silurian
of Lobenstein, and of Hostin, Bohemia, are of similar age. So is
Hostinella also from Hostin.—Bigsby’s “Thesaurus Siluricus,” p. 194.
Some plant-remains have been found in the Upper Silurian rocks of
the Hastern Hartz by Ad. Roemer, see “Siluria,” last edition, p. 591.
In the GrotocicaL Magazine for October, 1877, Count Saporta
has described a Fern, from the Lower or Middle Silurian Slates
of Angers, in France, as Hopteris Andegaversis. In 1859 Sir R.
Murchison mentioned the existence of faint traces of terrestrial.
vegetation in the Lower Silurian rocks of Scotland (“Siluria,”
p- 169). These are all the instances with which I am acquainted of
remains of land-plants in pre-Devonian rocks in the Old World. I
omit Hophyton as far too doubtful to be cited in evidence. ‘“'The
Eophyton of Torell, from a much lower horizon in Sweden,” says Dr.
Dawson, “I regard as a doubtful plant, similar forms being apparently ~
produced by impressions of feet or of fins upon mud. . . . Whatever
the nature of these forms, they are present in the Primordial of

1 These little organisms have been of late referred to Algee.—Eprror.

564 Reviews—Geological Survey of England and Wales.

America. Mr. Murray has found them in Newfoundland, and Mr.
Selwyn in Nova Scotia.” The EH. explanatum of Mr. Hicks from
the Lower Arenig (Llandeilo) rocks of Wales is apparently some-
thing quite different; and in microscopic structure would seem to
be similar to that of the Nematoxylon of the Devonian, if it be a
plant at all, and not a marine organism.—Dawson, “ Fossil Plants of
Canada,” 1871, p. 79.

I desire, in conclusion, to express my obligation to Dr. J. W.
Dawson, of Montreal, for valuable assistance willingly rendered, and
to Mr. Leo Lesquereux, of Columbus, Ohio, for kind and prompt
replies to letters of inquiry.’

dae WIRE WS

J].—Memorrs oF THE GroLocicaL SuRVEY oF EneLanp AnD WALES.
1. Tar Ervuptive Rocks oF Brent Tor anp 11s NEIGHBOURHOOD.
By Frank Rottey, F.G.S.
2. Tar Cuimmroip Fisues oF THE British Cretacrous Rocks.
By H. T. Newton, F.G.S. (London, 1878.)
YHE above works on very different subjects indicate the progress
of research carried on by the Geological Survey, and form
valuable additions to their other publications. The first memoir
comprises a description of a limited district around Brent Tor,
which was surveyed nearly fifty years ago by Sir H. De la Beche,
recorded in his Report on the Geology of Cornwall, Devon, and
West Somerset, to which work the investigations of Mr. Rutley
may be considered as a sequel. Within the district of about sixty
square miles occur many highly-interesting and peculiar eruptive
rocks, some intruded through, and others interbedded with, the
Carboniferous and Devonian strata which lie on the west of Dart-
moor. The object of the author being to elucidate (1) the mineral
composition and structure of the different rocks as observed in the
field, and of which a detailed account is given in the first part,
illustrated by some artistic sketches of their physical features and
other characters in plates 2 to 6; (2) to investigate, by means of
the microscope, the more minute structure of selected. specimens of
the rocks, a mode of research which, during the last few years, has
materially assisted the lahours of the petrologist ;—twenty-seven
different rocks are clearly described, and some of them are beauti-
fully illustrated by enlarged coloured figures (plates 8 to 10) from
Mr. Rutley’s careful microscopic drawings. The third part com-
prises remarks on the probable conditions under which the igneous

1 «Proceed. American Philosophical Society” (Philadelphia), vol. xvii. No. 100,
1877, p. 163, etc., Leo Lesquereux, ‘‘ On Land-plants recently discovered in the
Silurian Rocks of the United States.” Read October 19th, 1877; printed January
7th, 1878.

Psilophytum gracillimum (p. 164), sp. n.
cornutum (p. 165), sp. n.
Annularia Romingert (p. 166), sp. n.
Sphenophyllum primevum (p. 167), Lesqx.
Protostigma sigillarioides (p. 169), sp. n.—Eprror.

Reviews— Geological Survey of England and Wales. 565

and sedimentary rocks were formed, and the conclusions arrived at
from the observations made in the preceding parts (I. II.) serve to
show that the views entertained by Sir H. de la Beche are in the
main correct, and represent a vast amount of truth, derived simply
from observations in the field.

These three parts are preceded by some useful remarks on the
application of the microscope to petrological research, being the first
special petrographical work issued by the Geological Survey. In
this introduction the author dwells briefly upon the microscopic
characters of a very few of the common minerals which help to
form eruptive rocks, and of a few of the most interesting questions
relating to those rocks themselves. Besides which, he points out
how far the evidence to be derived from a microscopical examina-
tion of rocks can be relied on, and how far the older methods of
determination formerly, and now, at the field geologist’s disposal,
can assist, and in some cases rival, the work performed by more
elaborate appliances. This introductory essay will be a valuable
guide for the student in his investigation of the mineral composition
and minute structure of eruptive rocks.

2. The monograph by Mr. Newton on the Chimeroid fishes of the
British Cretaceous rocks may be considered as a continuation of
the description of fossil fishes published in the previous Decades of
the Geological Survey, and is the result of a careful investigation
of a large series of specimens in the Museum of Practical Geology,
the British Museum, and other collections, which are fully acknow-
ledged in the preface. This examination has materially increased
the knowledge of this group of fishes, and enabled the author to
correlate the various parts of certain known species, as well as to
establish species for the reception of several new forms, or varieties
related to them. As the author remarks, “Every paleeontologist will
appreciate the difliculty experienced in determining what differences
in fossil forms should be regarded as of generic, specific, or varietal
value. And bearing in mind the individual variations and the con-
sequent gradual evolution of new and distinct forms, which has
doubtless taken place in past times, it is obvious, that any lines of
division must of necessity be drawn more or less arbitrarily, and
although it is found convenient to make such divisions, yet from the
very nature of the case they must be to some extent unnatural.” In
the historical and general remarks, the previous labours of Dr.
Buckland are noticed, who first recognized (more than 40 years
ago) the Chimeeroid affinities of certain fossil beak-like bodies in
the Mesozoic and Tertiary strata. This group was further described
in two valuable memoirs, by Sir Philip Egerton (Quart. Journ.
Geol. Soc. 1848-47),who established five genera which have since
been universally adopted in this country.

As there has been some discrepancy between the authors who
have written about fossil Chimeeroids, in regard to the names given
to the different parts, Mr. Newton, in his remarks on the nomen-
clature, has explained the terms which are employed in this memoir,
and has also given in a tabular form the more important characters
of the genera.

Reviews—Geological Survey of England and Wales.

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Reviews—R. Etheridge’s Australian Fossils. 567

The species belonging to four genera are described; three of them
are British—Zdaphodon, Ischyodus, Elasmognathus; the fourth in-
cludes a species from the Cretaceous rocks of New Zealand, belong-
ing to the recent genus Callorhynchus. The twelve plates (which
might have been improved) fully illustrate the descriptions, and
show the correlation and characters of the different parts figured.

In comparing the prices of the above two Memoirs, there appears
to be something anomalous in their respective prices, one (Memoir
No. 1) being three times as much as the other, although each con-
tains the same number of pages, and the plates of the cheaper one
(twelve) exceeding both in number, fullness, and size those of the
other. Whether the cost of production of the two is very different,
or whether petrology ranks higher in the minds of the issue depart-
_ment than paleontology, and hence its greater price, or whether the
latter is the more favoured science, and hence furnished at a cheaper
rate, it is somewhat difficult to understand. These restrictive high
prices, as Mr. Rutley’s memoir and the previous ones by Mr. De
Rance and Mr. Skertchly, preclude the student from possessing
these real useful works.

The foregoing table of the generic characters of chimeeroid fishes
is taken from the author’s work.

II.—Atsrratian Paumontonoey.

A CataLoGuE or AUSTRALIAN Fossins (INCLUDING TASMANIA AND
THE IsLAND oF 'ImMoR) STRATIGRAPHICALLY AND ZoOLOGICALLY
ARRANGED. By Rozsert Erueripes, Jun., F.G.S. Hdited for
the Syndics of the University Press. 8vo. pp. 240. (Cam-
bridge: At the University Press, 1878; London: Deighton, Bell,
& Co.; and Cambridge Warehouse, 17, Paternoster Row.)

FJVHE distribution of Animal and Vegetable Life in former periods

of the Harth’s History must always be interesting to the geolo-
gist. Any Catalogue of Fossils therefore, whether of a Formation
or of a country, when carefully prepared, cannot fail to be a most
useful contribution to our knowledge.

Viewed in this light, we heartily welcome the list of Australian
Fossils by Mr. Robert Etheridge, jun., not only as an exceedingly
convenient work of reference, but also because it exemplifies in a
remarkable degree the rapid strides which the Geology and Palzon-
tology of Australia have made within a comparatively few years.

This work was originally commenced in-conjunction with his
former colleague Mr. Norman Taylor, in 1868, merely with a view
of carrying out more effectively their duties in connexion with the
Geological Survey of Victoria, on which Mr. Etheridge was at that
time an Assistant-Geologist. But the Survey (so ably conducted
by Mr. A. R. C. Selwyn, F.R.S.) was abruptly concluded by the
Victorian Government, before its completion, and the projected
Catalogue was for the time abandoned.

It was resumed, however, by Mr. Robert Etheridge, jun., alone in
1871, and he has since continued the task until its publication in
September of the present year; so that the work before us may be

568 Reviews—Australhan Geology.

considered as a faithful record of Australian Paleontology up to the
year 1878.

The genera and species are primarily arranged in zoological order —
in classes, but alphabetically under each class, for more ready and
convenient reference; the whole being divided into five stratigraphi-
cal subdivisions, viz.:—Silurian, Middle and Upper Paleozoic (in-
cluding the Devonian and Carboniferous), Mesozoic, Tertiary, and
Post-Tertiary. All the more important references are made to each
of the species, and the principal localities are also given; those
works in which a detailed description or figure is to be found are
denoted by an asterisk placed before them.

The great labour involved in preparing this Catalogue may be
partly estimated by stating that the list includes nearly 500 genera
and some 1450 species, and that the separate works, reports and -
papers consulted in the preparation of this Catalogue of Australian
and Tasmanian Fossils amounts to more than 500 in number.

Apart from the number of papers referred to for single species,
and for species identified with descriptions already published, the
Chronicles of Australian Paleontology have mainly been enriched by
the labours of Professor Owen, the Rev. J. EH. Tenison Wood, Prof.
FE. M‘Coy, Prof. L. G. de Koninck, Prof. P. Martin Duncan, Rev.
W. B. Clarke, Prof. J. Morris, Mr. R. Etheridge, and Mr. R. Ethe-
ridge, jun., Mr. W. Carruthers, Mr. C. Moore, Mr. J. W. Salter,
Prof. Dana, and Mr. Thomas Davidson.

The publication of this volume is due to the liberality of the
Syndics of the Cambridge University Press, who have thus conferred
a boon on the Colony of Australia and a great service to geological
science by enabling the author to produce in so excellent a form this

first attempt at a complete list of Australian Fossil Organic Remains.
J. M.

III.—Avstratian Guroroey.

1. Annuat Report or tHe Department or Mines, New Sovutu
WALES, FOR THE YEAR 1877. (Sydney, 1878.)

2. REMARKS ON THE SupIMENTARY Formations or New Souru
Watzs. By the Rev. W. B. Cuarxz, M.A., F.R.S. Fourth
edition. (Sydney, 1878.)

HE Report of more than 200 4to. pages on Mines and Mineral
Products of New South Wales comprises the results of the ex-
plorations of the Mining Registrars and Geological Surveyors, carried
on during 1877 in the different mining districts of that colony, and
contains much practical and statistical information, accompanied in
some cases by geological maps and sections of strata. During the
year, locality maps of three of the principal Gold Fields have been
completed, representing an area of about seventy-three square miles,
and many valuable additions have been made to the mineral and
fossil collections of the Department, and a collection has also been
forwarded to the Paris Exhibition, illustrative of the mineral re-
sources and geology of the colony. ‘The Report states that the
aggregate value of the minerals raised during the year 1877 amounts

Reviews —Richardson’s Geology of Edinburgh. 569

to £2,233,161 2s. 6d., showing a considerable increase over the
previous year, of which minerals, after coal, tin yielded the largest
amount, £508,540, exceeding that either of gold or copper, the other
metals, iron, antimony, and lead, being in far less proportions.

2. The work by the Rev. W. B. Clarke is probably the last of the
published results of his labours before his death (noticed p. 379),
and is only one among his many contributions to the advancement
of geological science, especially that of Australia, which has occupied
a considerable portion of his life. The present edition is the fourth
of a series, descriptive of the sedimentary formations of New South
Wales, the first of which was published in a catalogue of the natural
products of the colony forwarded to the Paris Exhibition of 1867,
and subsequently improved in the 2nd and 8rd editions (1870,
1876). It is now considerably enlarged, and contains much fresh
information brought up to the latest period, and is dedicated to the
Congress of Geologists assembled at Paris in connexion with the
International Exhibition of this year. The formations noticed are,
the Azoic and Metamorphic rocks, the Lower, Middle, and Upper
Palxozoic rocks, the Lower and Upper Mesozoic strata, and the
Tertiary rocks,—of the latter it appears that “throughout the whole
of Eastern Australia, including New South Wales and Queensland,
no Tertiary Marine deposits have been discovered. There are,
however, patches of plant deposits which may be referred to some
period of the Tertiary epoch,” (p. 89.) The Quaternary formation,
so interesting from the remarkable fossil remains found in it, and
the recent accumulations, are noticed in the last section. In this
memoir no general notice is taken of igneous rocks, but it may be
stated that there is, in all the various sedimentary formations noticed,
distinct evidence of the presence of igneous action, and their trans-
mutation through such and allied agencies has left an impress on
all the rocks more or less concerned.

Those interested in the comparative study of the sedimentary
strata will find Mr. Clarke’s paper of considerable value, as showing
the results of a continued study of the fossiliferous deposits of
Australia,—one of which at least, the Carboniferous formation, has
been the subject of some controversy, the main points of which are
fully discussed by the author, both as regards its contained fauna
and flora, and its connexion with other deposits in Australasia,
China and India (pp. 26-66), and which, as well as the remarks on
other formations, are supplemented by fifteen appendices containing
lists of fossils of New South Wales described by European paleon-
tologists.

IV.—Tue County or Epinsurcu, irs GroLocy, AGRICULTURE, AND
Merecorotogy. By Rapa Ricuarpsoy, F.R.S.H. (Edinburgh:
Adam and Charles Black, 1878.)

HIS essay fulfils what the title indicates, an account of the
geology, meteorology, and agriculture of the metropolitan
county of Scotland, preceded by some general observations on its
physical features, superficial area, subdivisions, and annual value of

570 Reviews—Gurney’s Manual of Crystallography.

the estimated acreage of property. This county has long been
considered a classical field to the geologist, as it presents some of
the finest examples of geological phenomena, whether as connected
with igneous or stratified rocks, or with physical and paleontological
geology. The main formations of Mid-Lothian are Paleozoic, from
the Silurian to the Carboniferous, with the associated igneous rocks,
over which is irregularly spread a more or less deep covering of
glacial or boulder clay.

The county of Edinburgh in regard to its agriculture takes a
high position. Not only have her farmers brought this science to a
standard of perfection rarely attained, but the agricultural produce
and value of land in the better portions of the county are ex-
ceptionally good. The relative value of the land is clearly shown
by means of colours on the agricultural map of the county accom-
panying this paper, and which is based on-Prof. A. Delesse’s
‘Carte Agricole de la France” noticed in this Macgazrne (Dee. II.
Vol. IV. p. 474). The annual rentals are given under nine divisions,
ranging from £1 to £20 and £40 per acre, these being dependent on
the nature of the soil and the favourable position of the farms, those
near the metropolis being the most highly rented. The meteorology
is simply considered with regard to the temperature, rainfall, and
altitude, these being the three main meteorological topics of agri-
cultural interest. This essay is certain to prove of value to those
interested in the district. i

V.—Manvats or Evemenrary Scrence. CRrysTanLocrapHy. By
Henry Patin Gurney, M.A. Fcap. 8vo. pp. 128, with 46
woodcuts. 1s. (London, 1878: Society for Promoting Christian
Knowledge.)

HE systematic study of scientific Crystallography has certainly
but few admirers, in this country at least. “Its great import-

ance to the chemist, the physicist, and the geologist cannot,” as the
author of the work which we are now noticing truly says in his
preface, ‘‘ be questioned.” The fact is, that the subject is beset with
mathematical abstruseness, and has been hitherto without suitable
introductory manuals. Many students have consequently been
driven to empirical systems, which are little better than the learning
by rote of a number of geometrical forms. We have met with
many other students whose knowledge of minerals is that only of
the chemist, or even of the miner. The object of the present little
work is to introduce the subject scientifically to the non-mathe-
matical. We are at a loss to know for whom such works as the
present, and Professor Clerk Maxwell’s Matter and Motion, in the
same series, are designed by their publishers; since surely the some-
what advanced students in special lines of scientific research, who
alone can appreciate them, would gladly pay double or treble their
price and possess the author’s ideas lucidly expressed in unconfined
space. ‘These manuals, however, certainly contain a vast amount of
useful matter. The two main points of merit in Mr. Gurney’s book
are, first, the clear, unmathematical text, supplemented by some

Correspondence—Mr. T. Mellard Reade. O71

mathematical matter in an appendix; and secondly, the natural
sequence adopted for the crystallographic systems, from the simplest,
viz. the Anorthic, to the most complex, the Cubic. This step,
analogous to that which makes our modern geologists and biologists
commence with Laurentian, Protozoa, and Protophyta, is one of the
greatest philosophical importance. Had space permitted it, we
should have liked a little more information on crystallogenesis, more
references to the history of the science, a description of the Reflective
Goniometer of Wollaston, and more detail in chapter xvii., which
treats of ‘the Physical Symmetry of Crystals.’ In a subsequent
edition we may suggest that the italicizing of all technical terms
when they first occur should be more uniformly carried out, that
more references to figures be inserted in the text, and that the dia-
grams for finding the symbol of a zone when those of two faces are
known, and for finding the symbol of a face common to two zones,
on pp. 28, 24, be made clearer. The term ‘holohedral forms’,
though mentioned in the index, is only defined by implication ;
‘deutosystematic’ on p. 72 should, we presume, be ‘deuterosyste-
matic;’ and Naumann’s Method of Projection is only attributed to
him in the ‘Contents’!! We would particularly call students’ atten-
tion to the excellent series of terms proposed by Professor Maske-
lyne, given on p. 54, and to Mr. Gurney’s triumphant proof, on
p. 59, that the three rhombohedral planes of symmetry represent the
holohedral type of the system, and that the double six-sided pyramid
is merely a combination of two rhombohedra. We sincerely con-
gratulate the author on his useful contribution to science; and can
only regret that the majority of those pupils whom he has, during
some years, instructed in the substance of this work, have gone to
India in a capacity in which science can only be the hobby of hard-
worked men; so that we can hope for but little fruit from their
knowledge of crystallography. G. S. B.

CORRES PON DENCE.

ae es
CLAY BOULDERS.

Srr.—An interesting phenomenon which may assist to explain the
structure of certain argillaceous rocks is now to be observed on the
Crosby shore near the River Alt.

Some time since a trench had been cut in the blue clay, which
underlies the Peat and Forest Bed,? in a south-westerly direction
across the shore. For many years this trough, though filled by the
tide at springs, has remained open, with simply a deposit of sand on
the bottom. I have not measured it, but I should judge the trench
to have been about fifty yards long, five feet wide, and two feet
deep. At the present moment it is filled up nearly to the surface
with an agglomeration of rounded lumps of clay more or less com-
pacted together. The clay boulders, for such they are, vary in size

1 Where his name even is mis-spelt.

* See “ The Submarine Forest at the Alt Mouth,” Quart. Journ. Geol. Soe. vol.
XXxXly. pp. 447-8, and other papers therein referred to.

O72 Correspondence—Ur. G. H. Kinahan—

from eighteen inches on the longer axis to the size of a bean, and
from a spherical to an ellipsoidal figure.

We have not far to seek for their origin, as a visit to the lower
edge of the peat frayed into a sort of subtidal cliff or series of cliffs
by the encroachments of the sea shows a deposit of similar clay
boulders at its base. In the neighbourhood of the trench the River
Alt meandering over the shore has made great inroads on the Post-
Glacial deposits, which compose the substratum, forming a subtidal
river cliff of blue clay on its western margin. Lumps of this clay
undermined by the currents, fall, break up into pieces, and get
rolled into boulders by the action of the tide. The trench has
formed a sort of trap for catching and retaining them. The clay-
boulders are in contact, and become in the trench compacted
together into one solid mass, so that if it were converted into rock
its structure would show in some cases distinct argillaceous boulders
in a sandy argillaceous matrix, and in others an imperceptible
shading of the boulder nucleus into the matrix.

Simply describing the foregoing facts for the information of those
interested, I leave geologists to apply the explanation to some of the
conglomerates, T. Mretiarp READE.

SIR RICHARD GRIFFITH AND THE OLD RED SANDSTONE.

Str,—The last big talk I had with the late Sir Richard Griffith
was immediately before the British Association Meeting in Belfast,
and it was on my work in West Galway and Mayo. Previous to it
I had left my maps and sections with him to examine after ex-
plaining them. During this conversation we discussed the age
of the Louisburgh Toormakeady and Croogh Moyle beds which had
been examined and proved to be of Silurian age, and Griffith pointed
out that the Curlew Mountain rocks and those near Firodes he always
believed to be of the same age and to be about equivalent to the Dingle
beds, “ but I never,” said he, “had time to examine them carefully,
and I left them in the Old Red Sandstone because they were very
like the conglomerates of the Comeraghs Galters and Knockmeal-
down Hills.” He also pointed out that there was a decided un-
conformability in the rocks said to belong to the ““Old Red Sandstone
formation”? in Ireland; while the newer rocks so called seemed to
be on different geological horizons. He concluded by saying, “My
work must remain as it is, but the working out of the question has
still to be done,” or words to that effect. Since then I have been
carefully examining into the question, starting on what was suggest-
ed to me by Griffith, and the results of my eo will be found in
my recently published Manual of Irish Geology. This is sufficient
to say at the present, as I hope to enter fully te the history of the
subject in a paper to be read before the Royal Geological Society of
Treland. G. Henry Kinanan.

Ovoca, IRELAND, 5th November, 1878.

Mr. B. J. Glanville—Rev. J. F. Blake—Mr. G. W. Lamplugh. 573

THE FOSSIL ANOMODONTIA OF SOUTH AFRICA.

Srr,—In the GronoercaL MaGazine, p. 569, is a notice of a paper
by Prof. Seeley on Procolophon, in which he remarked on the
presence of two distinct nares in this fossil. At the time the fossils
were sent to Professor Owen from this museum, we had not received
any but specimens more or less defective, especially at the apex,
but I had already requested Mr. Donald White, on whose farm at
Donnybrook they have as yet only been found, to try to get some
examples which would show the nostrils. This he has done; and
I have now before me a specimen in which the two distinct nares
are excellently shown. With regard to Professor Seeley’s idea that
the Procolophon is a parent type from which the dental modifica-
tions of Anomodontia have been derived, I would point out that
Tafelberg, on which the farm Donnybrook is situated, occupies a
geological position much higher than that of the Karoo-beds in
which Dicynodon is found. Hitherto this Tafelberg, formed of
horizontal beds, is the only place where Procolophon has been found,
so that it is improbable that it can have been the parent type of the
Anomodontia, without we make the assumption that it appeared at a
much earlier time than that for which we have any evidence. Above
the beds of the Tafelberg rise the equally horizontal and conformable
beds of the Stormberg, and in neither of these, so far as I know,
have any Dinosaurs or Anomodontia been found.

AtBany Musrum, GRAHAMSTOWN, B. J. GLANVILLE,

CapE oF Goop Hops, 12th Sept., 1878. Curator.

PALAOZOIC CEPHALOPODA.

Str,—Will you allow me to ask my brother-geologists, through
the pages of your Macazrtng, for the loan of any examples of British
Paleozoic Cephalopods which they may think of sufficient interest
to be noticed in a general work on that group, or likely in any way to
throw light upon the subject. Having been favoured with a Govern-
ment grant in aid of the publication of a “Synopsis of British Fossil
Cephalopoda,” I hope very shortly to offer the first part for subscrip-
tion, which will include the Paleozoic portion and be amply illustrated.
I am desirous of making it as complete an account of our British
fauna as possible, and this can only be done by the kind co-operation
of those who have valuable specimens in their collections, which, if en-
trusted to me, I need hardly say, will be returned in good condition.

11, Gaupen Roan, CrapHam, S.W. J. F. Buaxn.

THE BOULDER CLAY OF YORKSHIRE.

Sir,—Until recentiy, I was not aware that the existence of shells
in the “ Purple” Boulder-clay north of Flambro (the “ Purple clay
without chalk” of Mr. 8. V. Wood), had already been pointed out
in a paper by Mr. Leckenby “On the Boulder-Clay of East York-
shire,” Brit. Assoc. 1864, and more recently by Dr. J. Gwyn
Jeffreys in a “Note on the so-called Crag of Bridlington” (Rep.
Brit. Assoc. 1874). By a clerical error, the wrong initials have been
affixed tomy name in the paper published in your last Number, p. 509.

Bripiineton Quay, Nov. 16th, 1878. G. W. Lampuuesa.

574 OBLTUARY.

—>——_

PROFESSOR ROBERT HARKNESS; F.R.S., F.G.S.

Born 28rH Juty, 1816. Diep 47TH Octoper, 1878.

(Wirn A Porrrarr.)!

Those who have taken an active part in geological science during
the last quarter of a century must have been profoundly impressed
by the large number of notable geologists who have passed away
within that period.

But the cause may readily be discerned when we remember that
our science has only occupied a recognized position for about fifty
years, and that the young men, who were then its most active pro-
moters, have to a large extent fulfilled their allotted three-score
years and ten within this period, affording ample testimony to the
healthful nature of geological pursuits.

Tn a few instances, we have lost from our front ranks men whom
we had hoped to see still in their accustomed places for years to
come; but such special losses may have arisen from overwork
hastened by organic disease; and it is to be feared that this was
most probably the case with our late lamented friend Professor
Harkness.

Born at Ormskirk, Lancashire, July 28th, 1816, Robert Harkness
was sent at an early age to the High School, Dumfries, where under
Dr. Duncan’s care he received his primary education. Subsequently
he entered the University of Edinburgh, and here he seems to have
acquired his first love for geological science while attending the
lectures of Professor Jamieson and Professor James D. Forbes.
After the completion of his academic studies, he devoted himself
entirely to his favourite pursuits of chemistry and geology.

Mr. Harkness’s earliest researches seem to have been directed
to the investigation of that most attractive field of study to
geologists, the Carboniferous formation, his first paper being on
“The Climate of the Coal Epoch,” read before the Manchester
Geological Society, in April, 18438.

It is interesting to read the views of Harkness in this paper,
and to find them reiterated most remarkably by Professor T. Sterry
Hunt, twenty-four years later.’

Mr. Harkness writes :—

“From the foregoing observations it is evident that from the
first dawn of animal life, and probably also during the countless
ages which preceded the creation of organized beings, till the period
when terrestrial animals were first called into existence, the earth
possessed a warmer and a much more equable climate than at
the present time. This equable climate appears to have resulted

1 For permission to reproduce this likeness of the late Prof. Harkness, the Editor
is indebted to the kindness of the proprietors of The Illustrated London News.

2 See “The Chemistry of the Primeval Earth,’”’ a lecture by Professor T. Sterry
Hunt, F.R.S., F.G.S., Grou. Mac. 1867, Vol. IV. pp. 365-866.

IDs, Wi, Wilts Wa IAL OXIAY.

NEw SERIES.

GEOL. Mac. 1878.

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Obituary—Professor Harkness, F.R.S., F.G.S. 575

from the great density of the atmosphere which then surrounded
the globe; a density originating from the great quantity of carbonic
acid gas diffused through the atmosphere, and destined to support
that luxuriant vegetation which clothed the surface of the earth
during the coal era, and which is now deposited amongst the
strata which constitute the solid crust of the globe. This dense
atmosphere, from its capacity for absorbing heat, prevented, during
the period when the solar rays fall most obliquely on any part of
the earth’s surface, the dissipation of that heat acquired by the
earth during the time when the sun’s rays fall most directly, and
consequently prevented the occurrence of that degree of cold which
is so common to our present climate. By this means, most pro-
bably, have regions which are at present clothed with ice been
rendered fit for the abode of plants, which indicate a tropical
climate; and to this cause may be attributed that uniform tempera-
ture which existed during the earlier geological epochs, and which
we are justified in supposing to have prevailed from the extensive
geographical distribution of analogous forms of extinct vegetables.”

In the same year (1843) Mr. Harkness communicated to the
Geological Society of London a paper, “On Changes in the Tem-
perature of the Earth, as a Mode of accounting for the Subsidence of
the Ocean, and for the consequent Formation of Sea-beaches above
its present Level.” But it must not be supposed from this that
Harkness was merely a theoretical geologist; on the contrary, it
was, as his papers testify, in the field that he excelled. Hven
in these early years we find him in the Coal-measures exploring and
demonstrating with Mr. Binney the connexion between Sigillarian
stems and Stigmarian roots at St. Helen’s; tracing reptilian foot-
prints in the Bunter of Cheshire, and Dumfriesshire; working out
the Silurians of Dumfriesshire and Kirkeudbrightshire, and describ-
ing fourteen species of Graptolites discovered by himself in a
country hitherto very little explored, and where fossils were not
known to exist.

It is not.surprising to find him, when a candidate for the Chair
of Geology in Queen’s College, Cork, in 1858, supported by Prof.
Jamieson, Lieut.-Col. Portlock, Professor James Nicol, Hugh Hi.
Strickland, Sir H. T. de la Beche, Sir W. Jardine, Prof. Phillips,
Prof. Williamson, J. Beete Jukes, and many others. He was
appointed to succeed Professor Nicol in that year, but his duties
in Queen’s College did not deprive geology of his active labours in
the field; he simply added new explorations to his former areas,
and we find him at work, “On the Geology of the Dingle Pro-
montory, Ireland”; “The Lignites of the Giant’s Causeway” ; “The
Devonian Rocks around Cork”; “The Serpentines of Connemara” ;
“«The Annelide Tracks of County Clare”; and many other subjects
in connexion with Irish geology; ‘On the Siluriaitt Rocks of Cumber-
land and Westmoreland”; ‘“‘The Permians of the North-West of
England”; but it was especially the geology of the Lake District
latterly which engaged his attention.

About 1876 the syllabus for the Queen’s Colleges in Ireland was

576 Obituary—Professor Harkness, F.R.S., F.GLS.

altered, and Prof. Harkness found himself no longer merely Professor
of Geology, but required to lecture on Physical Geography, Geology,
Mineralogy, Paleontology, Zoology, and Botany! He complied with
the new regulations for 1877 and 1878, but he was overworking
himself, and being warned by premonitory symptoms of heart disease,
he resolved to resign his Chair at Cork, and rest quietly with his
sister in Penrith, where for some years he had made his home. This
he had done just previous to his last visit to Dublin in October which
proved fatal.

One! who was intimately acquainted with Professor Harkness
and his labours thus writes :—

“Tt is now some five-and-thirty years since the name of this able
geologist first appeared as a writer on his favourite science. During
this long period he had explored, on foot, the geology of large dis-
tricts in the north of England, in Scotland, and in various parts of
Jveland. The reports of the British Association and the Quarterly
Journal of the Geological Society bear witness to his industry and
to the painstaking minuteness of his method of investigation. To
him we owe our earliest exact information regarding the correlatives
of the reptiliferous sandstones of Dumfriesshire and Cumberland.
It was his patient labours continued year after year over ground
most difficult to unravel, that led the way to the working out of the
structure of the Silurian uplands of the south of Scotland. ‘To his
research, too, is due the identification of the metamorphic rocks of
the north-west of Ireland with those of the west of Scotland. To
the elucidation of every one of the Paleozoic system of deposits
he has contributed something of value. ;

« But important as was his scientific work, it had not a wider and
more hearty recognition among his brother geologists than his own
admirable qualities of head and heart. Who that has been privi-
leged with his friendship will not cherish the memory of his
earnestness over even the driest of details, his quiet enthusiasm, his
generous admiration for the work of others, his unfailing cheerful-
ness? Who will forget that beaming ruddy face, never absent from
the platform of Section C at the British Association meetings,
always ready to rise among the speakers there and to reappear at
the festive gatherings in the evening? There have been men who
have graven their names more deeply on the registers of scientific
thought and progress, but there have been few whose sunny nature
has more endeared them in the recollection of their friends than
Robert Harkness.”

Professor Harkness was the author of sixty-three papers, six of
which were joint productions (1) with Mr. John Blyth, (1) with
Edward W. Binney, F.R.S., (1) with Dr. Henry Hicks, (1) with
Sir Roderick I. Murchison, (2) with Prof. H. Alleyne Nicholson.
Eight of his papers have appeared in the pages of the GrorocicaL
Magazine, but they are for the most part in the Quarterly Journal
of the Geological Society and the Reports of the British Association.

1 Professor A. Geikie, F.R.S., ‘“‘ Nature,’ Oct. 10, p. 628.

INDEX.

—<—@——_—

ABE

ih ere eee ere , Geology of Neigh-
bourhood of, 532.

Across Europe and Asia, 29, 62.

Africa (South), Fossil Anomodontia
of, 578.

African Ammonites, Kast, 311.

Geology, West, 312.

America, Erratics at High Levels in
North-western, 209.

American Lake Region, Geology of
North, 455.

Surface Geology, 13.
Ammonites, East African, 311.
————— Zones of, 354.

Angelin, A. N. P., Silurian Crinoidea,
408.

Anomodontia of South Africa, Fossil,
573.

Antwerp, Geology of, 405.

Arbusculites argentea, Murray, 378.

Arctic Silurian or Devonian Fossils,
385.

Areas, Method of Estimating Geological,
352.

Asia, Across Europe and, 29, 62,

Atlas of Colorado, 365.

Aus Irland, 119.

Axe, Implements from Valley of the, 37.

Axis, Possible Changes in the Karth’s,
262.

AIKAL, Lake, to Kiachta, 29.
Barnwell Gravel, Flint Implements

from, 400.

Barrande, J., Cephalopoda of Bohemia,
361.

—— Survey of the Cephalopoda, 38.

Barrow-on-Soar, Leicstershire, New
Crustacean from Lower Lias, 289.

Bedwell, F. A., Bridlington Crag and
Boulder-clay, 517.

Beechey Island, Fossils from, 385.

Belgium, Fossil Crab in Coal-measures
of Mons, 433.

Belt, T., Death of. 529

DECADE II.—VOL. V.—-NO. XII.

CEP

Benwyan on Devonian Geology, 96.

Bigsby, Dr. J. J., Thesaurus Devonico-
Carboniferus, 310.

Bird, J. A., Geology of Channel Islands,
79.

Bittadon, North Devon, Felsite of, 207.

Bivalve Entomostraca, Fossil, 100.

Blake, J. F., Coral Rag of Upware, 90;
Paleozoic Cephalopoda, 573.

Blowpipe Apparatus Prize, 191.

Bohemia, Cephalopoda of, 361.

Bonney, Prof. T. G., Felsite of Bittadon,
North Devon, 207; Quartzite of Bun-
ter Conglomerate. 428.

Boulder-clay, 287, 517.

———— Marine Shells in, 509.

Preservation of Deposits

under, 73.

Boulders of Clay, 571.

Boulonnais, Lower, Fossil Brachiopoda
of, 436.

Brachiopoda, Fossil, of Lower Boulon-
nais, 436.

Bridlington Crag, 517.

——_——— Marine Shells in Boulder-
clay of, 509, 573.

British Association, Dublin, 411, 473.

Budleigh Salterton Pebbles, 233.

Bunter Conglomerate, Quartzites of, 239,
428,

Pebbles, Orthis redux in, 333.

Cae Valley of, in Yorkshire, 500.
Callaway, C., Correlation of Lower
Helderberg Group of New York, 271;
Fauna and Age of Shineton Shales,
332; Volcanic Rocks of Shropshire, 96.

Cameron, A. G., Peat Deposits of Kildale
and West Hartlepool, 351.

Canidz, Pleistocene, 282.

Carlsbad, Bohemia, Thermal Sources of,
521.

Cephalopoda, Barrande’s Survey of, 38.

———— — of Bohemia. 361.

| ————— Recent and Fossil, 487.

37

578
CHA

Chalk, English, Two or more Species of
Micrasters in? 116.

Chalk of Lewes, Sussex, New Crustacean
from, 5956.

Champernowne, A., Devonian and Old
Red Sandstone of North and South
Deyon, 193.

Channel Islands, Geology of, 79, 111.

— Metamorphism of Rocks

of, 86. |

China, Kalgan, Pekin, and Shanghai,
Trayels through, 62.

Chloritic Marl and Upper Greensand,
547.

Clarke, Rev. W. B., M.A., F.R.S., |

F.G.S., Obituary of, 379.

Clay Boulders, 571.

Claypole, Prof. E. W., Fossil Tree
(Glyptodendron) in Clinton Limestone
(base of Upper Silurian), of Ohio,
U.S., 558.

Climate, Theories of Geological, 390.

Clinton Limestone, of Ohio, U.S., Fossil
Tree from, 558.

Close, Rey. M. H., Extent of Geological
Time, 450; Errata in same Paper,
528. -

Coal-measures, Marine Beds in Lower,
144,

—+———— Mons, Belgium, Fossil
Crab in, 4383.

of Somersetshire, 345.

Supposed Radiolarians
and Diatomaceze of, 461.

“Coast Ice on Rising Area,” Reply to
Dr. Linnarsson, 426.

Cole, Rey. E. M., Age of Rocks of Monte
Generoso, 378.

Colorado, Atlas of, 365.

Concretionary Bands or Conglomerates
of Lambay Island, 48.

Conglomerate, Bunter, Quartzite of, 48.

_——— of Lambay Island, 48.

Coral Rag of Upware, 90.

Correlation of Lower Helderberg Group
ot New York, 271.

Correspondence, Benwyan, 96; Blake, J.
F., 90,573; Bonney, Prof. T. G., 428 ;
Callaway, C., 96, 332; Cole, E. M.,
879; Close, M. H., 528; Craig, R.,
480; Davis, W., 835; Feistmantel,
Dr. O., 92; Geikie, Prof. J., 287;
Glanville, B. J.,573; H. KE. H., 238;
Hill, E., 479; Hinde, G. J., 378;
Hudleston, W. H., 90; Jennings,
J. H., 289; Jones, Prof. T. R., 287;
Kinahan, G. H., 572; Lamplugh,
G. W., 573; Lapworth, C., 189;
Lebour, G. A., 422; Linnarsson, Dr.
G., 98, 188; Mackintosh, D., 190,
331; Milne, Prof. J., 425; Pengelly,
W., 2388; Penning, W. H., 480;

—_

——

Index.

DEV

Perceval, S. G., 883; Reade, T. M.,
148, 571; Theobald, W., 333; Ussher,
W. A. E., 237; Waters, A. W., 189 ;
Wood, 8. V.,jun., 187,335; Woodward,
H. B., 424; Wynne, A. B., 48, 185,334.

Crab in Coal-measures, Mons, Belgium,
Fossil, 433.

Crag of Bridlington, 517.

Craig, R., Geological Time, 479.

Crane, Agnes, Recent and Fossil Cepha-
lopoda, 487.

Cretaceous Deposits, Sawrocephalus lan-
ciformis from, 254.

Crickley Hill, Gloucestershire, Madre-
poraria of, 297.

Crinoidea, Silurian, 408.

Croll, Dr. J., Theories of Geological
Climate, 390.

Crustacean, New Undescribed Macrouran
Decapod, Peneus Sharpii, 164.

Crustacea, Fossil, described, 164, 289,433,
556.

Crystalline Rocks, Origin and Succession
of, 466.

——____ ——— of Donegal, 465.

Cycadaceous Plants of the Damudas, 92.

J \AINTREE, R., C.M.G., F.G.S.,
Obituary of, 429.

Damon, R., Great Northern Drift, 403.

Damudas, Cycadaceous Plants of, 92.

Davies, T., Jadeite and Jade, 192.

W., Nomenclature of Sawro-
cephalus lanciformis from British
Cretaceous Deposits, with Description
of New Species (S. Woodwardii) 254;
Pleistocene Mammals dredged off the
-Kastern Coast, 97, 483; Erratum in
lettering on Plate, 335.

Davis, J. W., Forces which have caused
Configuration of the Valley of the
Calder in Yorkshire, 500; Geology of
Yorkshire, 475.

Dawson, G. M., Erratics at High Levels
in North-west America, Barriers to a
Great Ice-Sheet, 209.

Decapod, Macrouran, Crustacean, New
Undescribed, 289.

Note on Peneus

Sharpit, 164.

Delesse and De Lapparent, Geological
Review, 282.

Denudation, Rain and River, 212.

Deposits under Till and Boulder-clay,
Preservation of, 78, 162, 287.

De Rance, C. E., Underground Waters,
462.

Devon, Devonian and Old Red Sandstone
of North and South, 193.

— North, Felsite of Bittadon, 207.

North, Section, Possible Expla-

nation of, 529.

Index.

DEY.

Devon, North, Rocks, The Late Prof.
Phillips on, 305.
Devonian Geology, 96.
of North and South Devon,
193.
Question, the late Prof. Phillips
on, 424.
or Silurian Fossils, from
Arctic Regions, 385,
Diyining Rod, 480.
Dixon, F., Geology of Sussex, 521.
Donegal, Crystalline Rocks of, 465.
Drift, Great Northern, 408.
Dublin, British Association, 411, 4738.
Geology of Environs, 457.
Dundee, Discovery of Ancient “ Kitchen
Midden”’ near, 310.
Dundas, Port, Lancaster Sound, Fossils
from, 385.
D’Urban, W. 8., Paleolithic Implements
from Valley of the Axe, 37.
Durham, J., Discovery of Ancient
‘¢ Kitchen Midden”’ near Dundee, 310.

5 ARTH’S Axis, Possible Changes in,

262.

Surface, Change in Latitudes on
the, 291, 551.

Eminent Living Geologists (5), Prof.
John Morris, M.A., F.G.S., 481.

England, Occurrence of Terebratula
Moriert in, 552.

Entomostraca, Fossil Bivalved, 100.

of the Wealden, 277.

Erratics at High Levels in North-west
America, Barriers to Great Ice-Sheet,
209.

Erratic? What is an, 185, 333, 334.

Etheridge, R., Jun., Australian Cata-
logue, 567 ; Paleontological Notes,
117, 269.

Europe and Asia, Across, 29, 62.

Kurope, Lake Dwellings of Switzerland
and other parts of, 227.

Europe, Tertiaries of Central, 165.

Evans, Dr. J., Address to Section C. of
British Association, 411.

Evolution of Tertiary Mammalia, 221.

ALSE-BEDDING, T. Fuchs on
Origin of, 311.
Fauna and Age of Shineton Shales, 332.
Fayre, E., Zones of Ammonites, 354.
Feistmantel, O., Cycadaceous Plants of
the Damudas, 92.
Felsite of Bittadon, N. Devon, 207.
Fenland, Geology of, 231.
Fenland, Past and Present, 360.
Fish Localities of Lebanon, Fossil, 214.
Fisher, O., Possibility of Changes in the
Latitudes of Places on the Earth’s
Surface, 291, 551.

579
GEO

Flint Implements from Barnwell Gravel,
400.

Foraminifera in Philippines, Miocene,
312.

Forbes, H. O., Denudation by Rain and
River, 212.

Freshwater Sponges in Purbeck Lime-
stone, 220.

Fuchs, on Origin of False Bedding, 311.

AUDRY, Prof. A., Evolution of
Tertiary Mammalia, 221.

Geikie, Prot. A., Geological Map of
Scotland, 128; Old Man of Hoy, 49.

Geikie, Dr. James, Preservation of
Deposits of Incoherent Material under
Till and Boulder-Clay, 287; Preser-
vation of Deposits under Till and
Boulder-clay, 73; reply to 8. V.
Wood, jun., 187.

Geinitz, H. B., Neues Jahrbuch, 478.

Generoso, Monte, Beds, 378, 422.

Geography and Geology of Ireland,

Physical, 121.
Geological Areas, Method of Estimat-
ing, 352.

—— Atlas of the Colorado, 365.
Climate, Theories of, 390.
History of North American

Lake Region, 455.

Map of London, 322.

of Scotland, 128, 189.

Review for 1875 & 1876, 282.

— Sketch of a Visit to Ireland

in August, 1876, 54.

Society of London, 42, 87,

136, 175, 233, 284, 323, 366.

— Survey of England and Wales,

Memoirs of, 230.

of India, 312.

of Ireland, Progress

of, 464.

Time, 154, 199, 450, 479.

Geologists’ Association, 134.

Geologists, Eminent Living, No. 5, 481.

Geologist’s View of the Age of the
World, 145.

Geology of Aberystwyth, 532.

— of Africa, 312.

—— American Surface, 18.

— of Antwerp, 406.

of Channel Islands, 79, 111.

Devonian, 96.

of Emperor Francis Joseph’s
Aqueduct at Vienna, 477.

—— of Environs of Dublin, 457.

of Fenland, 231.

———and Geography of Ireland,
Physical, 121.

of Punjab, Physical, 335.

of Sussex, 521.

——— of W. Yorkshire, 475.

580
GLA

Glacial Phenomena of Scandinavia, Prof.
Milne and the, 93.

Glanville, B. J., Fossil Anomodontia of
South Africa, 573.

Gloucestershire, Madreporaria of Crick-
ley Hill, 297.

Gorran Beds and Budleigh Salterton
Pebbles, 238.

Graptolite Schists of Sweden, 278.

Gravel, Barnwell, Flint Implements from
the, 400.

Greensand, Upper, and Chloritic Marl,
547.

Griffith, A. F., Flint Implements from

' Barnwell Gravel, 400.

Griffith, Sir R. J., Bart., LL.D., F.R.S.E.,
M.INST.C.E., M.RI.A., O24.

Griffith, Sir R., and the Old Red Sand-
stone, 572.

Grover’s Conversations with Little
Geologists on the Six Days of Creation,
316.

ALL, T. M., The late Prof. Phillips
on N. Devon Rocks, 305; Method
of Kstimating Geological Areas, 352.

Hardman, E. T., ‘‘ Hullite,’ an un-
described Mineral, 464.

Harkness, Prof., Obituary of, 574.

Hartlepool, West, Peat Deposits of, and
Kildale, 351.

Hartt, Prof. C. F., Obituary of, 336.
Hayden, F. V., Geological and Geo-
graphical Atlas of the Colorado, 365.
Heatherington, A., F.G.S., Obituary

Notice of, 336.

Hébert on Tertiaries of Central Europe,
165.

Helderberg Group of New York, Corre-
lation of Lower, 271.

Hicks, Dr. H., New Pre-Cambrian
Areas in Wales, 460.

Hill, Rey. E., Possible Changes in
Latitudes on the Earth’s Surface, 479;
Possible Change in Karth’s Axis,
262.

Hill’s (Rev. E.) Letter on Changes in
Latitudes of Places, Mr. Fisher’s reply
to, 551.

Hinde, G. J., Arbusculites argentea,
Murray, 378.

Hunt, Prof. T. 8., Origin and Succession
of Crystalline Rocks, 466.

Hippisley, H. E., Somersetshire Coal-
measures, 346.

“ Hoy, Old Man of,” 49.

Hudlestone, W. H., Coral Rag of Upware,
90.

Hull, Prof. E., Geology of Environs of
Dublin, 457; Progress of Geological
Survey of Ireland, 464; Physical

Index.

LAM

Geology and Geography of Ireland,
121, 167; Possible Explanation of
North Devon Section, 529.
‘ Hullite,” an Undescribed Mineral, 464.
Hutton Collection of Fossil Plants, 410.

MPLEMENTS, Flint, from Barnwell
Gravel, 400.
— from Valley of the Axe,

37.
India, Geological Survey of, 312.
Treland, Geological Sketch of, 54.
Physical Geology and Geography
of, 121.
Progress of Geological Survey of,

464.
Trish Silurian, Land Plants in, 398.
Irland, Aus, 119.
Italian Tertiaries, Dr. C. Mayer on, 189.

ADE and Jadeite, T. Davies on, 192.
Jennings, J. H., Origin of Quartzite

Boulder from Bunter Conglomerate,
Nottingham, 239.

Jones, Prof. T. R., Fossil Bivalved En-

_ tomostraca, 100; Sandworn Pebbles
in Wealden of Sussex, 287; Wealden
Entomostraca, 277.

Jukes-Browne, A. J., Formation of Till,
266.

ALGAN, Pekin,
Through, 62.

Karrer, F., Geology of Emperor Francis
Joseph’s Aqueduct, Vienna, 477.

Keeping, W., Geology of Neighbourhood
of Aberystwyth, 632.

Keller, Dr. F., Lake-Dwellings in Swit-
zerland and other parts of Kurope, 227.

Kiachta, Lake Baikal to, 29.

Kildale and West Hartlepool, Peat
Deposits of, 351.

Kinahan, G. H., Land Plants in Irish
Silurian, 398: Sir R. Griffith and the
Old Red Sandstone, 572.

King, Prof. W., Age of Crystalline Rocks
of Donegal, 465.

Kingsthorpe, near Northampton, Peneus
Sharpwi from, 164.

Kitchen Midden near Dundee, Discovery
of 310.

and Shanghai,

AKE-DWELLINGS of Switzerland
and other parts of Europe, 227.
' District, Mines and Mining in,

817.

- Region, North American, Geology
of, 455.
Lambay Island, Conglomerates of, 48.

Index.

LAM

Lamplugh, (J.) G. W., Marine Shells in
Boulder-clay of Bridlington and else-
where on Yorkshire Coast, 509, 573 ;
correction of name, 573.

Lancaster Sound, Fossils from Port
Dundas and Beechey Island, 385.

Land Plants in Irish Silurian, 398.

—— — in U. Silurian of N. America, 558.

in Silurian rocks, 356.

Lapworth, C., Geological Map of Scot-
land, 189.

Lasaulx, Dr. A. von, Aus Irland, 119.

Latitudes of the Earth’s Surface, Changes
in, 291, 479, 551.

Lebanon, Fossil Fish Localities of, 214.

Lebour, G. A., Hutton Collection of
Fossil Plants, 410; Marine Beds in
Lower Coal-measures, 144; Monte
Generoso Beds, 422.

Lees, F. A., Physical Geography and
Botanical Topography of West York-
shire, 475.

Lenz, Dr. O., West African Geology,
312.

Leonhard, K. C. von, Neues Jahrbuch,
478.

Lewes, Chalk of, a New Crustacean from
the, 556.

Lewis, Rev. E. R., Fossil Fish Localities
of Lebanon, 214.

Lias, Lower, Barrow-on-Soar, Leicester-
shire, New Crustacean from, 289.

Lias, Upper, Peneus Sharpii from, 164.

Limestone, Freshwater Sponge in Pur-
beck, 220.

Linnarsson, Dr. G., Coast Ice on Rising
Area, Reply to, 425; Graptolite
Schists of Sweden, 278; Prof. Milne
and the Glacial Phenomena of Scandi-
navia, 93; ‘Trilobites of Shineton
Shales, 188.

Liveing, Prof., Metamorphism of Rocks
of Channel Islands, 86.

London, Geological Map of, 322.

ACKINTOSH, D., Reply to Ussher
and H. E. H., 331; Terminal
Curvature of Slaty Lamine, West
Somerset, 190.
M‘Coy, Prof. F., Victorian Organic
Remains, 283.
Macrouran Decapod Crustacean, New,
289.

— Peneus Sharpii, 164.

Madreporaria of Crickley Hill, Glouces-
tershire, 297.

Mammalia, Evolution of Tertiary, 221.

Mammals, Pleistocene, from astern
Coast, 97, 433.

Mammoth Epoch and Apparition of
Man upon the Earth, 356.

581
OBI

Man upon the Earth, Apparition of, in
Mammoth Epoch, 356.

Marine Beds in Lower Coal-measures,
144,

Marine Shells in Boulder-clay, 509.

Marl, Chloritic, and Upper Greensand,
547.

Mathematician’s View of Age of World,
146.

Maw, G., Geological History of North
American Lake Region, 409.

Mayer, Dr. C., on Italian Tertiaries, 189.

Metamorphism of Rocks of Channel
Islands, 86.

Meyer, C. J. A., Two or more Species of
Micrasters from English Chalk? 119 ;
Chloritic Marl and Upper Greensand,
547.

Meyeria Willettii, a new Crustacean from
the Chalk, Lewes, 556.

Micrasters in English Chalk, Two or more
species? 116.

Milne, Prof. J., Across Europe and
Asia, 29, 62; “Coast Ice on Rising
Area,’ Reply to Dr. G. Linnarsson,
425; Form of Volcanos, 337.

Milne, Prof., and the Glacial Phenomena

of Scandinavia, 93.

Mines and Mining in Lake District, 317.

Miocene Foraminifera in Philippines, 312.

Mongolia, Across, 29.

Mons, Belgium, Fossil Crab in Coal-

measures, 433.

Monte Generoso, Age of Rocks of, 378,
422.

Montreal, Natural History Society of,
330.

Morgan, C. L., Geological Time, 154,
199; Physiography, 241.

Morris, Prof. John, Life of, 481.

Munier-Chalmas on Tertiaries of Central
Kurope, 165.

Ne History Society of Mon-
treal, 330.

Neues Jahrbuch, 1876 and 1877, 478.

New York, Correlation of Lower Hel-
derberg Group of, 271.

Nicholson, H. A., Recent Progress of
Paleontology, 1.

Nolan, J., Volcanic District of Slieve
Gullion, 445.

Northampton, Peneus
Kingsthorpe, near 164.

Sharpit from

BITUARY Notices of, T. Belt, 528 ;

Rev. W. B. Clarke, M.A., 336, 379;

R. Daintree, C.M.G., F.G.8., 336, 429 ;

Prof. R. Harkness, 574; Prof. C. F.

Hartt, 336; A. Heatherington, F.G.S.,

336; Dr. T. Oldham, F.R.8., 382;
J..Rofe, C.H., F.G.8., 239.

d82
OHI

Ohio, U. S., Fossil Tree in Clinton
Limestone of, 558.

Oldham, Dr. T., M.A., F.R.S., F.G.S.,
Obituary Notice of, 382.

Orthis redua im Middle Bunter Pebbles,
383.

Paraien ones. Implements of the
Valley of the Axe, 37.
Pal eontolen tall Notes,’ Ly, 269.
Paleontology, Recent Progress of, 1.
of Victoria, - 283.
Peat Deposits at Kildale and West
Hartlepool, 351.
Pebbles, Budleigh Salterton, 238.
— with Orthis redux in Middle of
Bunter, 333.
— in Wealden of Sussex, Sand-
Worn, 287.
Pekin, Shanghai, and Kalgan, Through,
62.

Peneus Sharpii, Note on, 164.

Pengelly, W., Gorran Beds and Bud-
leigh Salterton Pebbles, 238.

Penning, W. #., Divining Rod, 480.

Perceval, S. G., ‘Orthis redux in Middle
of Bunter Pebbles, 333.

Philippines, Miocene Foraminifera in,
312.

Phillips, The late Prof., on the Devonian
Rocks, 305, 424.

Physical Geology and Geography of
Ireland, 121.

Physiography, 241.

Plants, Cycadaceous, of the Damudas, 92.

Hutton Collection of Fossil, 410.

Illustrations of Fossil, 319.

in Irish Silurian, Land, 398.

in Silurian Rocks, 356.

of N. America, 558.

Pleistocene Canide, 282.

—— Mammals from East Coast,
97, 433.

Postlethwaite, J., Mines and Mining in
Lake District, 317.

Progress of Paleontology, 1

Purbeck Limestone, Freshwater Sponge
in, 220.

of the Punjab, 335.

UARTZITES of Bunter Conglom- |

erate, 239, 428, 573.

AIN and Rivers, Denudation by, 212.
Reade, T. M., Age of World as
viewed by the Geologist and Mathe-
matician, 145; Induced Structure of
Stone, 148; Clay Boulders, 571.
Recent Progress of Paleontology, 1

Index.

SUS

Reptiles, S. African, 5738.

Rigaux, E., Fossil Brachiopoda of Maver
Boulonnais, 436.

Rivers and Rain, Denudation, 212.

Rocks of Channel Islands , Metamorphism
of, 86.

of North Devon, the Late Prof.

Phillips on, 305.

of Shropshire, Volcanic, 96.

Roemer, Dr. F., Geological Sketch of
Visit to Ireland in August, 1876, 54.

ANDSTONE, Old Red, of North and
South Devon, 193.
Sandstone, the Old Red, and Sir R.
Griffith, 572.
Sand-worn Pebbles in Wealden of Sussex,
287.
Saurocephalus lancifor mis
Cretaceous Deposits, 254.
S. Woodwardii, W. Davies on, 254.
Scandinavian Glacial Phenomena, 93.
Schists of Sweden, Graptolite, 278.
Scotland, Geological Map of, 128, 189.
Silurian Crinoidea, 408.
Silurian or Devonian Fossils, Arctic, 385.
Land Plants in Ireland, 398.
in N. America, 558.
Rocks, Land Plants of, 356.
Shales, Shineton, Fauna and Age of, 332.
Shineton, Trilobites of, 188.
ee Kalgan, and Pekin, Through,

of British

eee Shales, Fauna and Age of, 332.

— Trilobites from, 188.

Shropshire, Volcanic Rocks of, 96.

Skertchly, 8. B. J., Geology of Fenland
Past and Present, 231, 360.

Slaty Lamine, Terminal Curvature of,
9

Slieve Gullion, Volcanic District of, 445.

Somersetshire Coal-measures, 345.

, West, Terminal Curvature
of Slaty Lamine, 190, 238.

Southall, J. C., Mammoth Kpoch and
Apparition of Man upon the Earth,
356

Sponge, Freshwater, in Purbeck Lime-
stone, 220.

Stanford’s Geological Map of London,
322.

Stone, Induced Structure in, 143.

Structure in Stone, Induced, 143.

Subglacial Origin of Till, 336.

Surface Geology of America, 13.

Survey of England and Wales, Memoirs
of, 231.

— India, Geological, 312.

— Ireland, Progress of Geological,

464.

Sussex, Geology of, 521.

Index.

SUS

Sussex Sand-worn Pebbles in Wealden
of, 287.

Sweden, Graptolite Schists of, 278.

Switzerland and other parts of Europe,
Lake-Dwellings of, 227.

‘EREBRATULA Morieri in Eng-
land, 552.
Tertiaries of Central Europe, 165.
Tertiaries, Italian, Dr. C. Mayer on, 189.
Tertiary Mammalia, Evolution of, 221.
Theobald, W., What is an Erratic ? 333.
Thermal Sources of Carlsbad, Bohemia,
O21.
Thesaurus Devonico-Carboniferus, 320.
Till, Formation of, 266.
Till, Preservation of Deposits under, 73,
162, 287.
Till, Subglacial Origin of, 335.

Tomes, R. F., List of Madreporaria of
Crickley Hill, Gloucestershire, 297.
Trail, W., Rocks of Ulster as source of

Water Supply, 463.
Tree, Fossil (Glyptodendron) in the
Limestone, Ohio, U.S., 558.
Trilobites of Shineton Shales, 188.

LSTER, Rocks of, as Source of
Water Supply, 463.
Upware, Coral Rag of, 90.
Ussher, W. A. E., Terminal Curvature
of Slaty Lamine in §.W. Counties,
237.

Nee’ of the Calder in Yorkshire,
500.

_ Vanden Broeck, E., Geology of Antwerp,
405.

Victorian Organic Remains, 283.

Volcanic District of Slieve Gullion, 445.

Rocks of Shropshire, 96.

Volcanos, Forms of, 337.

583
YOR

ALES, New Pre-Cambrian Areas
in, 460.

Walker, J. F. Occurrence of Terebratula
Moriert in England, 552.

Waters, A. W., Dr. C. Mayer on Italian
Tertiaries, 189.

Waters, Underground, C. E. De Rance
on, 462.

Wealden Entomostraca, 277.

— of Sussex, Sandworn Pebbles
in, 287.

Williamson, Prof. W. C., Supposed
Radiolarians, ete., of the Coal-mea-
sures, 461.

Woldrich, Prof. J., Pleistocene Canide,
282.

Wood, S. V., jun., American Surface
Geology and its relation to British, 13;
Reply to Dr. J. Geikie, 187; Sub-
glacial Origin of Till, 335.

Woodward, Dr. H., Arctic Silurian or
Devonian (?) Fossils from Beechey
Island, 385; Undescribed Macrouran
Decapod Crustacean from Lower Lias,
Barrow-on-Soar, 289; Note on Peneus
Sharpvi,a Macrourous Decapod Crusta-
cean from Lower Lias, Kingsthorpe,
164; Remains of Fossil Crab (Deca-
poda-Brachyura) in Coal-measures,
Mons, Belgium, 433; on Meyeria
Willettii, a new Macrouran from the
Chalk of Lewes, 556.

Woodward, H. B., Prof. Phillips on
Devonian Question, 424.

World, Age of the, as Viewed by Geo-
logist and Mathematician, 145.

Wynne, A. B., Conglomerates of Lam-
bay Island, 48; What is an Erratic ?
185, 384; Physical Geology of Pun-
jab, 335.

ORKSHIRHE, Geology of West, 475.

Young, Prof. J., What must be
explained before the Preservation of
Deposits under Till is explained, 162.

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