in the manner exemplified in _fig. 3, Lign. 26_; _figs._ 2, 4, 6,
are illustrated by _fig. 4, Lign. 26_; for the chalk specimens,
_Lign. 26_, shew that all these flints have been moulded around
_Ventriculites_, and that their diversity of figure has arisen from
the quantity of silex that happened to permeate the substance of the
zoophyte; if but a small portion, flint like _figs._ 2 and 4, were
the result; if the quantity were considerable, the larger fungiform
examples were produced.
Note IX. Page 50. _Minute Corals from Chalk._
Some layers of chalk are composed of an aggregation of many kinds of
delicate corals, the interstices being filled up with _Rotaliæ_ and
other foraminiferous shells. In the cliffs near Dover there are several
beds of this nature, well known to collectors for the profusion of
exquisite specimens they yield to the experienced investigator. _Lign.
17_, p. 50, represents several varieties from different localities;
the small figures shew the natural size, and the enlarged ones their
appearance when magnified. Attached to the surface of shells, and
sometimes standing erect in crannies of flint nodules, beautiful corals
may often be detected by the aid of a lens of moderate power. By
brushing chalk in water, and examining the deposit, delicate fossils of
this kind may also be obtained.[AR]
[AR] Refer to '_Medals of Creation_,' p. 284, and to '_Wonders of
Geology_,' _Lecture VI._ p. 588, for a comprehensive view of Recent and
Fossil Corals.
[Sidenote: NATURE OF CORALS.]
From the close analogy of the fossil corals to existing forms, it would
not be difficult to give restored figures of the originals. Every
little branch might be represented fraught with living polypes: in some
cells the agile inmates might be shown with the mouth expanded, and
the tentacula in rapid motion; in others withdrawn into their stony
recesses, and devouring the infinitesimal atoms that constitute their
food: even their varied hues might be introduced, and thus a vivid
picture be presented of the microscopic beings which peopled the waters
of the ancient chalk ocean.
That the Corals, which from their elegance and beauty are preserved in
almost every cabinet, have been fabricated--or, in other words, built
up--by polypes, in the same manner as the honey-comb of the bee and
wasp, is so prevalent yet erroneous an opinion, that I am induced to
point out its fallacy, by giving a brief account of the formation of
these substances. The three recent specimens represented in _Lign. 27_
will serve to illustrate my remarks.
[Illustration: Lign. 27:--Recent Corals.
1. _Oculina ramea._
2. _Madrepora muricata._
3. _Isis hippuris._
]
The coral, _fig. 1_, was an internal axis or skeleton, deposited by the
soft fleshy integument with which, when living, it was wholly invested;
in the same manner as are the bones of animals, by the special membrane
(_periosteum_) that secretes them. This integument lined every cell,
and the polypes were permanently united to it. When the live coral is
taken out of the water, the animalcules shrink up and quickly perish;
their soft parts and the external investing substance putrefy, and the
stony axis beset with the radiated cells alone remains.
[Sidenote: RECENT CORALS.]
In the example of _Oculina ramea_, or May-blossom Coral, _fig. 1_, from
the Mediterranean, the cells are large and distinct; in the _Madrepore_
from the West Indies, _fig. 2_, they are small and very closely
aggregated.
The specimen of _Isis_ (_fig. 3_) belongs to a group of coral-zoophytes
in which the polype-cells consist of a substance that is durable, but
not so hard as coral, and invests an axis composed of a tough flexible
material, which is exposed at the base of _fig 3_, by the removal of
the external or cortical part in which the polypes were situated. The
_Gorgonia_, or Venus's fan, has a similar structure and composition.[AS]
[AS] See '_Wonders of Geology_,' vol. ii. p. 616.
In the _Red Coral_, so largely employed in the manufacture of beads,
brooches, and other ornaments, not only the animalcules, but also
their receptacles, are composed of a soft perishable substance. When
alive, the polypes, as well as the investing fleshy integument, are of
a delicate bluish tint; the internal calcareous axis alone possesses
the peculiar red colour. Upon being taken out of the sea, vitality
quickly ceases, the soft parts decompose, and the beautiful crimson
stone commonly known as the _true coral_, is obtained free from all
traces of the soft mass by which it was secreted. Although an actual
investigation of the facts described can only be instituted near the
seas of warm climates, yet our coasts abound in certain coral-zoophytes
in which similar phenomena may readily be observed. Most persons in
their rambles by the sea-side must have noticed on the fuci, algæ,
shells, pebbles, &c., patches of a white earthy substance, which
when closely examined resemble delicate lace-work. These apparently
calcareous incrustations are clusters of the zoophytes termed
the _Flustra_, or sea-mat.[AT] When removed from the water, this
aggregation of polypes seems coated over with a glossy film or varnish;
and with a lens of moderate power the surface is seen to be full of
pores, disposed with much regularity. If viewed under the microscope
while immersed in sea-water, a very different appearance is presented.
Every pore is found to be the opening of a cell whence issues a tube
fringed with several long feelers or arms; these expand, then suddenly
contract and withdraw into the cell, and again issue forth; the whole
surface of the Flustra being covered with these hydra-like animalcules.
The Flustra, therefore, like the corals, constitutes an assemblage of
polypes, each individual being permanently fixed in a durable cell,
and the whole attached to a common integument by which the calcareous
frame-work was secreted and maintained.[AU]
[AT] See '_Wonders of Geology_,' Plate 5.
[AU] See Dr. Johnson's beautiful work on '_British Zoophytes_,' in
which are numerous figures of various species of Flustra.
Note X. Page 53. _Infusorial earth from Richmond in Virginia._
[Sidenote: INFUSORIAL EARTHS.]
The greatest natural operations are produced by the most simple
and apparently inadequate agents: for as the illustrious Galileo
emphatically remarked, "_La nature fait beaucoup avec peu, et ses
opérations sont toutes également merveilleuses._" The profound thinker
Hobbes, in the same spirit observes, "The majesty of God appeareth no
less in small things than in great, and as it exceedeth human sense in
the immensity of the universe, so also doth it in the smallness of the
parts thereof." This sublime truth is strongly impressed on the mind
of the geological inquirer, who perceives that whole countries and
mountain ranges of great elevation and extent, are wholly composed of
the aggregated remains of beings of such infinite minuteness that but
for the powerful optical instruments of modern times, their presence
would never have been suspected.
A few years only have elapsed since the sagacious Ehrenberg first
drew attention to this subject, and pointed out the proper method of
investigation;[AV] and so rapid has been the progress of discovery in
this department of science, that _infusorial deposits_, as these beds
of fossil animalcules are designated, have been detected in every
quarter of the globe. A fact equally unexpected and remarkable has also
been established, namely, that at the present moment similar minute
living agents are largely contributing to the increase of the solid
materials of the crust of our planet.
[AV] See '_Medals of Creation_,' p. 244, for instructions for the
microscopical examination of earths, chalk, &c.
[Sidenote: RICHMOND EARTH.]
The infusorial earth of Virginia, alluded to in the text, is a
yellowish siliceous clay, forming a deposit from twelve to fifteen
feet in thickness, upon which the towns of Richmond and Petersburgh
are built. The surface of the country over which it extends is
characterized by a scanty vegetation, owing to the siliceous nature of
the soil dependent on the minute organisms of which it almost entirely
consists. When a few grains of this earth are properly prepared for
microscopic examination, immense numbers of the shields or cases of
animalcules are visible under a magnifying power of 300 diameters; in
fact, the merest stain left by the evaporation of water in which some
of the marl has been mixed, teems with these fossil remains.[AW]
[AW] Specimens of Infusorial earths, prepared for the microscope, may
be obtained of Mr. Topping, 4, New Winchester Street, Pentonville Hill,
New Road, London.
These organisms are of exquisite structure, and comprise many
species and genera. The most beautiful and abundant are the circular
shields, termed _Coscinodisci_ (sieve-like disks), which are elegant
saucer-shaped cases, elaborately ornamented with hexagonal apertures
disposed in curves, somewhat resembling the engine-turned sculpturing
of a watch; these shells are from 1/1000 to 1/100 of an inch in
diameter. A segment of one of these disks, highly magnified, is
represented in _Lign. 18, fig. 2_. The body of the living animalcule
was protected and enclosed by a pair of these concave shells, the
perforations admitting of the exsertion of filaments or tentacula.
This species of _Coscinodiscus_ abounds in the present seas, and
constitutes no inconsiderable proportion of the food of Pectens and
other testaceous mollusca.[AX]
[AX] See '_Thoughts on Animalcules_,' p. 103.
All the animalcules found in the Richmond earth are marine, and most
of them belong to genera, and many to existing species; although the
position of the American strata proves that they are referable to a
period of immense antiquity.
In Germany, beds of a white infusorial earth, resembling magnesia
in appearance, and termed _Bergh-mehl_, or fossil farina, occur at
Bilin, and several other places: at San Fiora in Tuscany, near Egra
in Bohemia, in the Bermudas, Barbadoes, &c., similar deposits have
been discovered; all being composed of the shields of various kinds of
animalcules. But I must not extend these remarks, and will only add a
few observations on the infusorial earth of Barbadoes, which has but
recently been brought under the notice of geologists by Sir Robert
Schomburgk, and is especially interesting for the exquisite beauty and
variety of its organisms, and the circumstances under which the deposit
occurs.
[Sidenote: FOSSIL INFUSORIA OF BARBADOES.]
Barbadoes, an island of the West Indies, is about twelve miles in
length from north to south, and consists of coral reefs, capped in one
district by tertiary sandstones and limestones, which attain a height
of 1200 feet above the sea. Over the rest of the island, coral reefs
form the entire surface, which is divided by vertical walls of coral,
some of them nearly 200 feet high, into six terraces, indicating as
many periods of upheaval. In the lowest reef, Indian hatchets have
been found twenty feet above high water mark; shewing that the last
movement, at least, took place within the human period. The tertiary
strata are more or less inclined, and in many places vertical, and
contorted. Strata of marl, several hundred feet thick, predominate; and
there are beds of bituminous coal, sandstone, clays, and ferruginous
sands. Arenaceous limestone containing teeth of sharks, spines of
echini, and shells, forms the summit of a hill nearly 1,000 feet high.
The white marls abound in 300 species of the most beautiful siliceous
infusoria; many are peculiar, others the same as occur in the Richmond
earth, and some belong to recent species.[AY]
[AY] Sir R. H. Schomburgk: Brit. Assoc. 1847.
THE END.
* * * * *
WORKS BY THE SAME AUTHOR.
_In 2 Vols, foolscap 8vo, cloth, lettered, with numerous Illustrations
and Coloured Plates, price 18s. the Sixth Edition of_
THE WONDERS OF GEOLOGY;
OR,
A FAMILIAR EXPOSITION OF GEOLOGICAL PHENOMENA.
By GIDEON ALGERNON MANTELL, Esq., LL.D., F.R.S,
Vice-President of the Geological Society of London.
"Dr. Mantell's _Wonders of Geology_ will continue to be a favourite
work equally in the Geological schools, in the private study, and in
the family circle. It may be read and understood by any intelligent
and educated individual; its exact science, sound logic, and dignity
of style ensure its acceptance with the learned; its elegance,
beauty, and perspicuity, with the polite and refined; and its
comprehensive brevity, with the student of the elements of Geology.
It realizes, indeed, our beau-ideal of a familiar yet dignified
philosophical style: being alike condensed and luminous, possessing
a graceful flowing eloquence, and rising as the subject may require,
into the sublime as well as the beautiful. We are not aware of the
existence of any work, on any department of science, which has higher
claims at once to a place in the library of the philosopher, and on
the table of a refined family."--_Review of the American Edition of
the Wonders of Geology._ _American Journal of Science._
"Dr. Mantell's eloquent and delightful work, the Wonders of
Geology."--_Sir E. B. Lytton._
_In 2 vols. foolscap 8vo, cloth, lettered, with Coloured Plates, and
several hundred Figures of Fossil Remains, price One Guinea._
THE MEDALS OF CREATION;
OR,
FIRST LESSONS IN GEOLOGY, AND IN THE STUDY OF ORGANIC REMAINS.
These volumes comprise a Popular Introduction to the study
of Organic remains, and a general view of Fossil Botany and
Zoology.
Geological Excursions to some of the most interesting places
in England are described, in illustration of the method of observing
and investigating Geological Phenomena, and of collecting Organic
Remains.
Ample instructions are given for the development and arrangement
of Fossil _Vegetables_, _Corals_, _Shells_, _Bones_, _Teeth_, &c.:
and practical directions for the microscopical examination of
rocks composed of Fossil Infusoria, and the intimate structure of
mineralized Plants, Teeth, &c. In fine, these volumes are offered
as a popular guide and hand-hook for the Student and Amateur
Collector of Fossil Remains, and the Reader who may desire a general
acquaintance with a science replete with objects of the highest
interest; and for the Tourist who may wish, in the course of his
travels, to employ profitably and agreeably a leisure hour, in the
various districts he may visit. Such a work has long been required;
and the present will be found to comprise all that can reasonably be
expected in two pocket volumes. The plates are alike beautiful and
faithful representations of the originals.
"Very rarely can we find a work which is so perfect an example of
the art of book, making, in the best understanding of that term; we
mean technically and _mechanically_ as well as _intellectually_.
Dr. Mantell's 'Medals of Creation' are, indeed, among the
_chef d'oeuvres_ of the art; and, being elegantly bound in embossed
covers, of the still portable size of the larger 12mo, will and
must take their place as the companions, not only of the geologist
in his study, but in the field; while they will also accompany
the intelligent travellers of both sexes as most instructive and
delightful Mentors in their journeyings among the grand and beautiful
scenes of our globe. This work is a _classic of high excellence_,
of great research, and formidable labour; and we cannot close our
remarks without again expressing our admiration of the perspicuity,
method, and condensation by which it is distinguished."--_American
Journal of Science for January_, 1845.
_In one volume square 8vo, with 12 coloured plates; price 10s._
THOUGHTS ON ANIMALCULES;
OR,
A GLIMPSE OF THE INVISIBLE WORLD REVEALED BY THE MICROSCOPE.
"In this beautiful work Dr. Mantell has presented a vast deal of
information on the most interesting genera and species of Infusoria,
and clothed it with that fascinating garb, that persuasive eloquence,
with which he has been ever wont to impart knowledge."--_Westminster
and Foreign Quarterly Review._
_In one volume 8vo, with numerous plates, sections, coloured geological
maps, &c.; price 12s._
GEOLOGICAL EXCURSIONS ROUND THE
ISLE OF WIGHT
AND
ALONG THE ADJACENT COASTS OF HAMPSHIRE AND DORSETSHIRE.
Illustrative of the most interesting geological
phenomena and organic remains.
This work is a popular guide to the geology of the "beautiful Island,"
pointing out and explaining the most remarkable localities and the
fossils with which they abound; not only of the Isle of Wight, but also
of the Isles of Purbeck and Portland.
_In one volume, with plates; price 5s._
A DAY'S RAMBLE IN AND ABOUT THE
ANCIENT TOWN OF LEWES;
ILLUSTRATIVE OF THE OBJECTS OF HISTORICAL, GEOLOGICAL, AND
ANTIQUARIAN INTEREST OF THE TOWN AND NEIGHBOURHOOD.
"A charming guide to a charming spot; rich in picturesque scenery,
and historical associations of the highest interest. A day's ramble
which every one who visits Brighton and has leisure will not fail to
undertake with so instructive and delightful a companion."--_Brighton
Gazette._
_Preparing for Publication._
THE PHENOMENA OF THE NERVOUS SYSTEM;
OR,
A FAMILIAR EXPOSITION OF THE NATURE AND FUNCTIONS OF THE NERVES:
Being the substance of a course of popular Lectures.
_In one volume, with numerous illustrations._
* * * * *
_August, 1850._
=LIST OF WORKS=
PRINCIPALLY ON
NATURAL AND PHYSICAL SCIENCE,
PUBLISHED BY
REEVE AND BENHAM,
5, HENRIETTA STREET, COVENT GARDEN.
1.
POPULAR FIELD BOTANY;
COMPRISING
A familiar and technical description of the Plants most common to the
British Isles, adapted to the study of either the Artificial or Natural
System.
By AGNES CATLOW.
=Second Edition.=
_Arranged in twelve chapters, each being the Botanical
lesson for the month._
"A useful aid to young persons at a loss how to take the first steps
in Botany. One of the impediments in their way is the uncertainty
that attends all attempts at making out the names of the objects they
have to examine, and this impediment can only be removed by drawings
and very familiar descriptions. Miss Catlow, in the work before us,
has furnished a clear and concise supply of both. We recommend her
'Popular Botany' to favourable notice."--_Gardeners' Chronicle._
"The design of this work is to furnish young persons with a
Self-instructor in Botany, enabling them with little difficulty to
discover the scientific names of the common plants they may find in
their country rambles, to which are appended a few facts respecting
their uses, habits, &c. The plants are classed in months, the
illustrations are nicely coloured, and the book is altogether an
elegant, as well as useful present."--_Illustrated London News._
[***] In one vol. royal 16mo, with twenty plates of figures.
Price 7_s._ plain; 10_s._ 6_d._ coloured.
2. INSTINCT AND REASON. By Alfred Smee, F.R.S., Author of
'Electro-Biology.' One vol. 8vo. With coloured Plates by Wing,
and Woodcuts. 16_s._
3. THE TOURIST'S FLORA. A Descriptive Catalogue of the Flowering
Plants and Ferns of the British Islands, France, Germany,
Switzerland, Italy, and the Italian Islands. By Joseph Woods,
F.A.S., F.L.S., and F.G.S. 8vo.
4. POPULAR HISTORY OF MAMMALIA. By Adam White, F.L.S., Assistant
in the Zoological Department of the British Museum. With
sixteen coloured Plates of Quadrupeds, &c., by B. Waterhouse
Hawkins, F.L.S. Royal 16mo. 10_s._ 6_d._
5. VOICES FROM THE WOODLANDS; or, History of Forest Trees,
Lichens, Mosses, and Ferns. By Mary Roberts. With twenty
coloured Plates by Fitch. Royal 16mo. 10_s._ 6_d._
6. THOUGHTS ON A PEBBLE; or, A First Lesson in Geology. By Dr.
Mantell, F.R.S. Eighth Edition, considerably enlarged. With
four coloured plates, twenty-seven woodcuts, and a Portrait of
the Author. Square 12mo. 5_s._
7. THE POETRY OF SCIENCE; or, Studies of the Physical Phenomena
of Nature. By Robert Hunt, Esq., Author of 'Panthea.' Second
Edition. Revised by the Author. With an Index.
"An able and clever exposition of the great generalities of Science,
adapted to the comprehension of those who know little of her
mysteries."--_Athenæum._
"One of the most readable epitomes of the present state and progress
of science we have yet perused."--_Morning Herald._
"This book displays a fund of knowledge, and is the work of an
eloquent and earnest man."--_Examiner._
[***] One vol. demy 8vo. Price 12_s._
8. EPISODES OF INSECT LIFE. First Series.
"The letterpress is interspersed with vignettes clearly and cleverly
engraved on stone, and the whole pile of natural history--fable,
poetry, theory, and fact--is stuck over with quaint apophthegms and
shrewd maxims, deduced for the benefit of man from the contemplation
of such tiny monitors as gnats and moths.--Altogether the book
is a curious and interesting one--quaint and clever, genial and
well-informed."--_Morning Chronicle._
[***] One vol. crown 8vo, with 16 illustrations. Price 16_s._ elegantly
bound in fancy cloth. _Coloured and bound extra, gilt, 21s._
9. EPISODES OF INSECT LIFE. Second Series.
[***] One vol. crown 8vo, with 36 illustrations. Price 16_s._ elegantly
bound in fancy cloth. _Coloured and bound extra, gilt, 21s._
10.
POPULAR HISTORY
OF
BRITISH SEA-WEEDS;
Comprising a familiar and technical description
of the Sea-weeds of the British Isles.
By the Rev. DAVID LANDSBOROUGH, A.L.S.,
Member of the Wernerian Society of Edinburgh.
"This charming contribution to the study of a very interesting branch
of Natural History combines scientific correctness with artistical
beauty."--_Literary Gazette._
"The book is as well executed as it is well timed. The descriptions
are scientific as well as popular, and the plates are clear and
explicit. Not only the forms, but the uses of Algæ, are minutely
described. It is a worthy sea-side companion--a hand-book for every
occasional or permanent resident on the sea-shore."--_Economist._
"A work of much general interest, and one which every dweller by
the sea-side, who makes a right use of his eyes, would do well to
procure."--_Edinburgh Witness._
"Mr. Landsborough's very beautiful volume is meant for young students
of Sea-weeds. The volume is illustrated with many coloured plates,
executed in a superb style."--_Glasgow Daily Mail._
"Profusely illustrated with specimens of the various Sea-weeds,
beautifully drawn and exquisitely coloured."--_Sun._
"This elegant work, though intended for beginners, is well worthy the
perusal of those advanced in the science."--_Morning Herald._
"Those who desire to make themselves acquainted with British
Sea-weeds, cannot do better than begin with this elegantly
illustrated manual."--_Globe._
[***] In one vol. royal 16mo, with twenty-two plates of figures
by Fitch. Price 10_s._ 6_d._ coloured.
11. PANTHEA, THE SPIRIT OF NATURE. By Robert Hunt. Author
of 'The Poetry of Science.' One vol. 8vo. Price 10_s._ 6_d._
"A brave attempt to range from the elemental to the universal, from
the known to the unknown."--_Literary Gazette._
"There is, throughout, the closeness of matter and eloquence of style
that distinguish the 'Poetry of Science.'"--_Spectator._
12. A REVIEW OF THE FRENCH REVOLUTION OF 1848. By Captain Chamier,
R.N. Two vols. 8vo. Price 21_s._
13. THE NATURAL HISTORY OF IRELAND. By William Thompson, Esq.,
President of the Natural History and Philosophical Society of
Belfast. Birds. Vol. I. Price 16_s._ cloth. Vol. II. Price
12_s._
14. THE RHODODENDRONS OF SIKKIM-HIMALAYA. By Dr. J. D. Hooker.
Second Edition. In handsome imperial folio, with ten
beautifully coloured plates. Price 21_s._
15. TRAVELS IN THE INTERIOR OF BRAZIL, principally through the
Northern Provinces and the Gold and Diamond Districts, during
the years 1836-41. By George Gardner, M.D., F.L.S. Second and
Cheaper Edition. 8vo. Plate and Map. Price 12_s._
16. ILLUSTRATIONS OF BRITISH MYCOLOGY; or. Figures and Descriptions
of British Funguses. By Mrs. T. J. Hussey. Royal 4to. Ninety
plates, beautifully coloured. Price 7_l._ 12_s._ 6_d._, cloth.
17. THE ESCULENT FUNGUSES OF ENGLAND, By the Rev. Dr. Badham.
Super-royal 8vo. Price 21_s._, coloured plates.