BEAUTIFUL SHELLS:
THEIR NATURE, STRUCTURE, AND USES
FAMILIARLY EXPLAINED;
WITH DIRECTIONS FOR
COLLECTING, CLEANING, AND ARRANGING THEM
IN THE CABINET;
DESCRIPTIONS OF
THE MOST REMARKABLE SPECIES,
AND OF THE CREATURES WHICH INHABIT THEM;
AND EXPLANATIONS OF
THE MEANINGS OF THEIR SCIENTIFIC NAMES,
AND OF
THE TERMS USED IN CONCHOLOGY.
BY H. G. ADAMS,
_Author of “Nests and Eggs of Familiar British Birds,” “Beautiful
Butterflies,” “Favourite Song Birds,” “A Story of the Seasons,”
&c. &c._
ILLUSTRATED WITH NUMEROUS ENGRAVINGS & COLOURED PLATES.
LONDON:
GROOMBRIDGE AND SONS, 5, PATERNOSTER ROW.
M DCCC LVI.
INTRODUCTION.
WHAT ARE SHELLS?
Dr. Johnson gives us no less than eight different meanings for the
word SHELL. First, he calls it ‘The hard covering of anything; the
external crust.’ Second, ‘The covering of a testaceous or crustaceous
animal.’ And here we may stop, for this is just the signification
which has to do with our subject; so let us turn the sentence inside
out, and see what we can make of it. We all know what a covering is—an
outer coat, a case, a protection from injury, a husk, a crust, a—in
short, a shell,—_scyll_ or _scell_, as our Saxon forefathers called it;
_schale_, as the Germans now term it. No Latin nor Greek here, but the
good old Saxon tongue, somewhat rough and rugged, perhaps, but stout
and sturdy, and honest and serviceable; a kind of language to stand
wear and tear, like a pair of hob-nailed shoes, with little polish, but
useful, yes, very useful! Well, we have got so far, now comes a hard
word—TES-TA-CE-OUS, what can it mean? It is pronounced _tes-ta-shus_,
comes from the Latin _testaceus_—having a Shell, and means consisting of,
or composed of shells; so we find that a _testacean_ is a shell-fish,
and _testaceology_ is the science of shells. Johnson’s second meaning of
the word _testaceous_ is ‘Having continuous, not jointed shells, opposed
to crustaceous.’ So we find that some naturalists call those testaceous
fish, “whose strong and thick shells are entire and of a piece, because
those which are joined, as the lobsters, are crustaceous.”
Now some of the true testacean have shells in more than one or two
pieces, and therefore this last explanation of the term is rather
calculated to mislead a learner; but we shall explain presently wherein
the difference consists between them, and the CRUS-TA-CE-OUS, or, as
we pronounce it, _krus-ta-shus_, fish consists. Here is another long
word, it comes from the Latin _crusta_, a word of many meanings, all
having reference to an outer coat or covering. My readers know all about
pie-crust, and have perhaps heard a surly, snappish, peevish person
called a crusty fellow; they will now understand what is meant by a
_crustacean_ and _crustaceology_, that part of Zoology which treats
of crustaceous animals. They constitute quite a large family, these
_ologies_, and have a strange way of twisting themselves about, and
exchanging limbs and features, so that one is puzzled at times to tell
which is which. But here we have fixed two of them, called TESTACEOLOGY
and CRUSTACEOLOGY, twin brothers, and very much alike in their
characteristics. Let us have a good look at them, so that we may know
them again if we should lose sight of them for awhile. Now we will spell
over the name of the first—
CONCHOLOGY.
Why, it is changed already? Has this science of shells then another name?
Yes, and this is it, pronounced _kong-kol-o-gy_, and derived from the
Latin _concha_, which means properly a shell-fish with two shells, joined
by a hinge, as the oyster, the cockle, etc. This present volume then is
a work on _Conchology_, the subject of it is _Conchiferous_, and whoever
studies it will be doing something towards becoming a _Conchologist_.
So much for names and titles; but still we have the question to answer,
What are shells? In a learned work called a Cyclopædia, we find it
stated that “shell is the hard calcareous (that is chalky) substance
which protects, either partially or entirely, the testaceous mollusks
externally, or supports certain of them internally.” All this you will
understand, except perhaps the word ‘mollusks;’ this is a term applied
to soft-bodied animals, such as shell-fish, snails, etc., about which we
shall have more to say as we proceed. By this we learn that _all_ shells
are not external or outer coverings, some are internal or inner supports
for the soft, jelly-like bodies to which they belong, thus performing
the duty of bones. An example of this is seen in the shell of the Cuttle
Fish, called by naturalists _Sepia_, a description of which will be found
further on in the book.
Shells are either _Crystalline_ or _Granular_. Now look at those two
words, they almost explain their own meaning. Crystalline shells are
those which have more or less of clearness, transparency as we say, so
that if held against the light it shews through them; they are sometimes
called _Porcellaneous_ shells, from their resemblance in this respect to
porcelain, or chinaware; the Common Cowry, (_Cypræa Tigris_,) is a shell
of this description.
_Granular_, or, as they are sometimes called, _Concretionary_ shells,
are the most hard and compact; it is in these that the substance called
_nacre_, or _mother-of-pearl_, is mostly found. One of the commonest
examples is the oyster shell; if broken across it will be seen to consist
of very thin plates, or _laminæ_, as they are termed, closely packed
together. The thinner these laminæ may be the more lustrous and beautiful
appears the lining of the shell; that shifting play of colours which we
call _iridescent_, from iris—the rainbow, is then brightest and most
noticeable. A very remarkable substance is this mother-of-pearl; smooth,
and shining, and delicately-tinted. Who would expect to find such a
beautiful lining to the rugged, rough, dingy-looking oyster, or mussel
shell? Truly these mollusks, some of them, live in gorgeous palaces. And
the most curious part of the matter is that from the fluids or juices, of
their own bodies, and from the chalky matter collected from the water,
they are enabled to secrete or deposit such wonderfully-constructed
habitations, which after all are little more than chalk. Burn a heap
of oyster shells, or any other testaceous coverings, and you get
lime the same as that produced by burning the white lumps from the
chalk-pit, which lumps, by the way, are said to be composed wholly, or
for the most part, of marine shells. This we should call _cretaceous_
matter, from _creta_, which is the Latin for chalk, or _calcerous_,
from _calcis_—lime. Granular shells you have been told are sometimes
called _concretionary_, this is because they contain a large amount of
this chalky deposit. The rock called limestone, geologists tell us, is
composed entirely of fossil shells and mud, or what was once mud, dried
and hardened, most likely by extreme heat, to the consistence of rock.
Wonderful this to think of; huge mountains, and mighty masses, and
far-stretching strata, forming a large portion of the crust of the earth,
made up chiefly of the coverings of fishes, a great portion of them so
small as to be scarcely visible to the naked eye.—Truly wonderful! But
we shall have more to say upon this head when we come to speak of Fossil
Shells, as well as on the subject of Pearls, in our chapter on the fish
in whose shells they are chiefly found.
It has been a matter of dispute with naturalists whether the testaceous
mollusks have shells at all before they issue from the egg, and the main
evidence favours the opinion that, generally speaking, they do possess
what may be considered as a kind of pattern or model of the habitation
which they are to build. This appears to be of a pale horn-colour, and
destitute of any markings; but as soon as the animal enters upon an
independent state of existence, it begins to assume its distinctive shape
and colour, gradually increasing with the growth of its living tenant,
and becoming more and more decidedly marked, until it attains its full
perfection of testacean development. Thus the age of some shell-fish can
be at once determined by the peculiar conformation and markings of the
shell.
The relative portions of animal and earthy, or rather chalky matter,
which compose these shells, varies considerably in different kinds; in
those called Crystalline or Porcellaneous, the animal deposit is much
less than in the granular or concretionary shells, where it not only
constitutes a large part of the whole substance, but is more dense,
that is thick, and also has the appearance of being membraneous, or
organized matter. We can perhaps best explain this by saying that whereas
the different chalky layers of the crystalline shell seem merely glued
together by the intervening animal fluid; those of the granular shell, as
the oyster, appear to be connected by interlacing membranes. But all this
my readers will learn more about from more advanced and scientific works
if they proceed, as I trust they will do, in the study of CONCHOLOGY, a
science which has in a greater or less degree attracted the attention
of curious and contemplative minds in all ages, and the study of which
it has been well said is peculiarly adapted to recreate the senses,
and insensibly to lead us to the contemplation of the glory of God in
creation.
BEAUTY AND VALUE OF SHELLS.
In shells, as in all the works of the Almighty Creator, we may observe
an infinite variety of form, and if they do not all strike us as alike
graceful, yet in each, however plain and simple, there is some peculiar
beauty, whether it be the mere hollow cup, or the simple tube, the smooth
or twisted cone, the slender spire, the convoluted oval, or half circle,
ribbed or spiked, with a lip curving out like the leaf of a water lily,
or a narrow rim, like that of a golden chalice; they are indeed elegant,
each perfect of its kind, and bearing the impress of a constructive skill
far above that of man, who copies from them some of the most graceful and
elegant designs wherewith to ornament his buildings, and shapes in which
to fashion his articles of luxury or utility.
The most beautiful scroll-work of marble chimney-pieces, cornices of
rooms, and other enriched portions of both public and private structures,
are those in which the forms of shells have been taken for the patterns
of the artistic designs; and how tasteful and appropriate is the
employment of the shells themselves as ornaments for the mantle-piece,
side-board, and chiffonniere. Then too,
“The rainbow-tinted shell, which lies
Miles deep at bottom of the sea, hath all
Colours of skies, and flowers, and gems, and plants.”
Not only has it grace and elegance of form, but it has also richness,
and delicacy, and variety of colouring. In some species the tints are
intensely vivid as the shifting lights of the aurora borealis, or the
glowing hues of an autumnal sunset; in others pale and delicate as the
first indications of coming morn, or the scarcely-perceptible tinge of a
just expanding flower-bud; in some the colours are arranged in patterns,
regularly disposed; in others, in masses and blotches, of varying shapes
and degrees of intensity; in some again they seem to change and melt one
into the other, like the prismatic hues of the rainbow. In all, whether
distinct and unconnected, or intimately blended, whether regular or
irregular, they are beautiful exceedingly. Nor is their beauty of an
evanescent, that is fading, or vanishing character; unlike plants and
animals, which when once dead, are extremely difficult of preservation.
Shells, being composed of particles already in natural combination, are
almost indestructible; unless exposed to the action of fire, or some
powerful acid, they will remain the same for ages, requiring no care or
attention, beyond occasionally removing the dust, which would collect
upon and defile their pearly whiteness, or obscure the brilliancy of
their colours.
So easily collected, arranged, and preserved, and withal so singular and
graceful in form, and rich and various of tint, one cannot wonder that
Shells have always had a conspicuous place in all museums, and other
collections of natural history objects; neither can we feel surprised
that a high value should have been set upon rare specimens; as much as
a thousand pounds it is said has been given for the first discovered
specimen of the _Venus Dione_; another shell called the _Conus cedo
nulli_, is valued at three hundred pounds; and the _Turbo scaloris_,
if large and perfect, is worth one hundred guineas; while the _Cypræa
aurantium_, or Orange Cowry, if it has not a hole beaten through it, will
fetch fifty guineas. It has been calculated that a complete collection of
British Conchology is worth its weight in silver.
The following quotation is from “The Young Conchologist,” by Miss
Roberts;—our readers will do well to peruse it attentively:—“We admit
that shells are beautiful, and that they are admirably adapted to the
exigencies of the wearers; but how shall we account for the endless
diversity of shades and colours, varying from the sober coating of the
garden snail, to the delicate and glowing tints which are diffused over
some of the finer species, in the infinite profusion of undulations,
clouds and spots, bands and reticulated figures, with which these
admirable architects enrich the walls of their beautiful receptacles. The
means of producing them must be sought for in the animals themselves.
Their necks are furnished with pores replete with colouring fluid, which
blends insensibly with the calcareous exudation already noticed, and
thus occasions that exquisite variety in their testaceous coverings,
which art attempts to emulate, but can never fully equal. Thus far is
the result of observation and experiment. It now remains to account for
the extraordinary fact that the stony exudations of testaceous animals
condense only on those parts where they are essential to their welfare.
But here investigation ends—the microscope has done its office. It
seems as if material nature delighted to baffle the wisdom of her sons,
and to say to the proud assertors of the sufficiency of human reason
for comprehending the mysteries of creation and of Providence, ‘Thus
far can you go, and no farther; even in the formation of a shell, or
its insignificant inhabitant, your arrogant pretensions are completely
humbled.’”
USES OF SHELLS.
In speaking of shells as ornaments, and objects worthy of our study and
admiration, we have already mentioned some of their uses, for surely that
which contributes to the intellectual improvement and innocent pleasure
of mankind, is in its degree useful. But on the more narrow ground of
utility, shells may also claim a high place in our estimation. To man in
a barbarous and uncivilized state, they furnish the means of performing
some of the most important operations of daily life, being extensively
used as a substitute for iron. The savage frequently forms his knife, his
hunting spear, and his fish-hook of hard shell. Lister relates that the
inhabitants of Nicaragua, in South America, fasten a shell, called the
_Ostrea virginica_, to a handle of wood, and use it as a spade. In North
America the natives use a blue and white belt composed of shells called
the _Venus mercenaria_, as a symbol of peace and unity, and there too
the gorget of the chieftain’s war-dress is composed of the pearl-bearing
mussel, called by naturalists _Mytilus margaritiferus_. Many African
tribes use the _Murex tritonis_ as a military horn, and a rare variety of
this shell, which has the volutions reversed, is held sacred, and used
only by the priests. Among the Friendly Islanders the Orange Cowry is a
symbol of the highest dignity. The Money Cowry, (_Cypræa moneta_,) forms
the current coin of many nations of Africa; and a certain number of these
shells strung together, are considered by the slave-hunting chiefs, as
an equivalent for so many black-skinned brothers, whom they sell into
hopeless bondage.
Among nations, too, in a high state of civilization, shells are often
used for economical as well as ornamental purposes. To say nothing of
mother-of-pearl, which is converted into so many articles useful as well
as pretty, scallop, or oyster shells, are frequently employed as scoops
by druggists, grocers, and the like; and in the country the dairy-maid,
with the larger kinds of the same shell, skims her milk, and slices her
butter; while sometimes by the poor people of both towns and villages,
the deeper specimens are converted into oil lamps. One very important
use, my young readers will understand, when I speak of a ragged urchin,
who shouts to every passer-by—‘Please remember the grotto!’
In ancient times, we are told, the people of Athens recorded their votes
on public occasions, by marks upon a shell, thus Pope says—
“He whom ungrateful Athens would expel,
At all times just, but when he signed the shell;”
in allusion to this custom, of which we are reminded by such English
words as _Attestation_, a certifying, a bearing witness; _Testify_, to
give evidence; _Testament_, a will, or written disposal of property,
etc.; all having their origin, it appears, in the Latin _testa_—a shell.
In ancient poetry we find the word _Testudo_ used to signify a musical
instrument, also called a lyre or lute, which instrument, according to
tradition, was first made by passing strings, and straining them tightly,
over the shell of a tortoise. So the poet Dryden, describing those who
listened to the music drawn from this simple invention, says—
“Less than a God they thought there could not dwell,
Within the hollow of that shell
That spoke so sweetly.”
A Greek writer, called Apollodorus, gives this account of the invention
of music by the Egyptian god Hermes, more commonly known as Mercury. The
Nile having overflowed its banks, and laid under water the whole country
of Egypt, left, when it returned to its usual boundaries, various dead
animals on the land; among the rest was a tortoise, the flesh of which
being dried and wasted by the sun, nothing remained within the shell
except nerves and cartilages, or thin gristly bones; these being shrunk
and tightened by the heat, became sonorous, that is sounding. Against
this shell Mercury chanced to strike his foot, and pleased by the sound
caused thereby, examined the shell from which it came, and so got a
notion, as we say, how he might construct a musical instrument. The first
which he made was in the form of a tortoise, and strung with the dried
sinews of dead animals, even as are the lutes, harps, and fiddles of the
present day. This fanciful mode of accounting for the origin of music, is
thus alluded to by a writer named Brown:—
“The lute was first devised
In imitation of a tortoise’ back,
Whose sinews parched by Apollo’s beams,
Echoed about the concave of the shell;
And seeing the shortest and smallest gave shrillest sound;
They found out frets, whose sweet diversity
Well touched by the skilful learned fingers,
Roused so strange a multitude of chords.
And the opinion many do confirm,
Because _testudo_ signifies a lute.”
And now we are among the myths and fables of antiquity, we may just
mention another application of the shell to musical purposes. Neptune,
who, according to the Grecian mythology, was the god of the sea, is
frequently represented as going forth in his car in great state and pomp,
with a body-guard of Tritons; some of whom go before with twisted conch
shells as trumpets, with which we are to suppose they make delightful
harmony. Venus, too, the goddess of beauty, rode on the ocean foam in a
testaceous car. Thus Dryden says, that Albion—our native land, so called
on account of its chalky cliffs, from the Latin _alba_—white:—
“Was to Neptune recommended;
Peace and plenty spread the sails;
Venus in her shell before him,
From the sands in safety bore him.”
But without believing all these fables, more poetical than true, we may
soon convince ourselves that in the hollow chambers of a shell, there
does seem to dwell, like an imprisoned spirit, a low sad kind of music.
An English poet, named Walter Savage Lander, has well described this in
these lines—
“Of pearly hue
Within, and they that lustre have imbibed
In the sun’s palace porch, where, when unyoked,
His chariot wheel stands midway in the wave;
Shake one, and it awakens; then apply
Its polished lips to your attentive ear,
And it remembers its august abodes,
And murmurs as the ocean murmurs there.”
Wordsworth, too, gives a beautiful description of a child applying one of
these pearly musical-boxes to his ear.
Many other uses of shells might be mentioned, to show that they perform
an important part in the operations of nature, as the means and modes
by and in which God sees fit to order the affairs of this world are
frequently called; and also promote the ends of science, and the arts of
every-day life. By the decomposition of the shells, of which they are
partly composed, solid rocks frequently crumble to pieces, and spreading
over a considerable surface, form a fruitful soil for the nourishment
of vegetation. The character of the testaceous deposits, too, enable
geologists, as those who study the nature and structure of the earth
are termed, to come to important conclusions on many points connected
with the subject of this investigation. And if we include, as the
subject of our book allows, the inhabitants of shells, how wide a field
of usefulness opens before us. How many thousands of our industrious
population depend wholly, or in part, upon the capture and sale of
shell-fish for their support. In some parts, as the western and northern
Islands of Scotland, they have in times of scarcity afforded sustenance
to the dwellers on the bleak and barren shores, who but for them must
have perished. But of all this we shall have more to say when we come
to describe the different members of the testaceous family. We will now
offer a few remarks upon
THE INHABITANTS OF SHELLS;
Which belonging to that division of Natural History called the
_Mollusca_, from the Latin _Mollis_—soft; these _Molluscous_ animals,
then, are animals having a soft body, and no internal skeleton. You may
be quite sure that a _Mollusk_ will never break its bones, because it has
none to break; it has a shell, however, which may be broken, at least in
some cases, for all _Mollusks_ have not snug habitations of the kind; but
wander about the watery or earthy world in which they live, quite naked;
such as the sea and land slugs, and some worms, leeches, etc.: but with
these we have nothing to do, our present subject including only a part of
MALACOLOGY,
another member of that queer ology family, deriving its name from two
Greek words signifying soft, and a discourse; hence it means a discourse
upon soft, or soft-bodied, animals, that is _mollusca_. It is only a part
then of _Malacology_ that we have to do with; that part which relates
to the shell-inhabiting mollusks, and strange creatures enough some
of these are. We will have a look at them presently; just now it will
be sufficient to observe that the _mollusca testacea_, or soft-bodied
animals, furnished with shells, possess the power of exuding, that is,
discharging from various parts of their bodies a sticky kind of fluid,
which mixing with the chalky matter collected from the water, and
becoming hard, forms, in process of time, the shelly covering which is at
once a dwelling and a defence for the inhabitant.
Miss Pratt, in her delightful book on “Common Things of the Sea Coast,”
observes of these shells that, “We gather up those which we find, and
looking at their structure would fain know something of the inmate of
such a dwelling. All nature proclaims the goodness of God. We hear that
the bird which wings its way over our heads has a song of joy; the bee
hums delightedly by us; and the little shrimp which darts in the clear
pool, seems full of merriment. Was the inmate of the shell less cared
for by its Maker? No doubt the little builder had some sense of joy, as
he framed from his own substance the house which excites our admiration.
Doubtless his existence, short and sluggish as it was, had its own
consciousness of pleasure; and obscure as is his history, and little
calculated as such a creature might seem to perform an important part
in the economy of creation, yet we know that he had a work to do, not
only for the living creatures of the sea, but for the well-being of man
himself.”
CLASSIFICATION OF SHELLS.
The great naturalist Linnæus divided shells into thirty-six genera,
each of which comprised a number of species; of these species somewhere
about two thousand five hundred have been described and classified; the
varieties, more or less distinct, are almost countless. Of shells found
on and about the British Isles, there are about five hundred and fifty
species, or, we should rather say were, for diligent enquirers into this
branch of Natural History, are almost daily adding to the number.
We have already seen that shells are sometimes called _Crystalline_,
and sometimes _Granular_, in accordance with certain peculiarities of
construction before mentioned: this is one mode of division; there are
several others made use of in different systems of arrangement, which
only a deeper study of the subject than can be here entered upon, would
enable one to understand; the plainest and most common, however, is that
which has reference to the form of the shell, which is one of these—
[Illustration:
UNIVALVE. BIVALVE. MULTIVALVE.
Whelk. Mussel. Barnacle.]
These words are derived from the Latin, _unus_—one, _bi_—two,
_multus_—many, and therefore it may at once be seen that they apply to
shells having one, two, or several pieces or divisions. Valve comes from
the Latin _valva_, and means a folding door, a lid, a piece moving on a
hinge, as the divisions in several of these shells do.
This order of arrangement is generally followed by those who make a
collection of shells for a cabinet; and to this we shall adhere as at
once the most simple and convenient, when we come to describe the several
species of testaceous mollusks. We will now say a few words on
TAKING AND PRESERVING SHELLS.
A diligent searcher along any beach or coast line, will be sure sometimes
to light upon curious and valuable specimens, and especially after
violent storms may such be sought for, with the greatest chance of
success, for the agitation of the waters will then have loosened them
from their natural beds and dwelling-places, and cast them on the shore.
Very frequently, however, they will be so beaten about and defaced, that
they will be comparatively valueless; if enveloped in tangled masses of
sea-weed, they are likely to be preserved from injury; and such heaps
of uprooted marine vegetation will often afford a rich harvest to the
young conchologist, who should always carefully examine them. Many of the
shells are so minute as scarcely to be seen with the naked eye, therefore
this search can scarcely be properly effected without the assistance of a
pocket lens, the cost of which is but trifling. The undersides of pieces
of stranded timber, the bottoms of boats lately returned from a fishing
voyage, the fisherman’s dredge or net, the cable, and the deep-sea
line; all these may prove productive, and should be looked to whenever
opportunity offers; nor should the search for land and fresh-water shells
be neglected, for many of these are very curious, as well as beautiful,
and no conchological collection is complete without them. For these, the
best hunting grounds are the ditch side and the river bed, the mossy
bank and the hedge-row; amid the twining, serpent-like roots of the old
thorn and elder trees; the crevices of the garden wall, the undersides of
stones, and all sorts of out-of-the-way holes, nooks, and corners, where
may be found the Striped Zebra, and other prettily-marked snail shells,
and many other kinds worthy of a place in—
THE CABINET;
which may be either large or small, plain or handsome, in accordance
with the means of the collector. Perhaps for a beginner just a nest of
shallow drawers in a deal or other case, may be quite sufficient; these
drawers should be divided into compartments, on the front side of each
of which should be pasted a neatly written label, with the common and
scientific name of the species of shell contained in it, together with
brief mention of the date when, and the place where, it was taken; and
any observations relating to it which can be comprised in a few words,
and may seem to the collector of sufficient interest to warrant their
insertion. This would be a good beginning; by and by, when the collection
is large, the knowledge more ample, and the outlay can be spared, it will
be time to think of something ornamental—mahogany and glass, and carved
or inlaid work, such a Cabinet as would properly display and enhance the
beauties of your testaceous treasures, which are too often stowed away,
with other natural curiosities, in a very disorderly, higgledy-piggledy
sort of manner, like the collection described by Dryden.
“He furnishes his closet first, and fills
The crowded shelves with rarities of shells;
Adds orient pearls, which from the wave he drew,
And all the sparkling stones of various hue.”
When live shells, as they are called, that is having the living fish
in them, are obtained, the best plan is to place them in spirits of
wine, this at once deprives the inhabitant of life, without injuring
the shell, which should then be placed in hot water for a time, the
body of the mollusk is thus rendered firm, and may be removed by means
of some pointed instrument; care should be taken to leave no portion of
animal matter within, or after a while it will become putrid and give
out a stain, which will show through and injure the delicate markings
of the shell; the surest, most expeditious, and least troublesome mode
of cleansing a shell, is to place it in an ant heap for a day or two;
the busy little insects will penetrate into its inmost cavities, and
remove hence all offending matter. There will be no difficulty in this
respect with the multivalve and bivalve kinds, which are only kept closed
by means of a set of muscles, which can be tightened or relaxed at the
pleasure of the animal within, and become powerless to keep the shell
closed as soon as that is dead. Great care must be taken to preserve
unbroken the smaller parts of these shells, such as the hinges or teeth,
as on the structure of these the scientific arrangement into genera
chiefly depends; the beard also, as it is called, and silky threads, must
not be removed, as these have much to do in determining the particular
species.
River and land shells are generally very thin and brittle, and must be
carefully handled; their colours are not usually so brilliant as those
of the marine species, but they form links in the testaceous chain, which
are necessary to a proper study and elucidation of conchology.
The most glowing and gorgeous of all shells are those brought from the
Tropical seas, and, excepting in a few rare instances, specimens of most
of these can be obtained at little cost from any dealer, or from sailors
returning from a voyage. If it is necessary to send either those, or
British shells, any distance, or to pack them away in a small compass,
the best plan is to wrap them separately in soft paper, place them in a
box, and then pour in sawdust, bran, or fine sand, very dry, until all
the open spaces are completely filled up.
ON CLEANING AND POLISHING SHELLS.
All shells, whether inhabited or not, when taken should be soaked for
a while in hot water, to remove the dirt which may adhere to them, and
dissolve the saline, that is salt, particles contained in the sea water;
they should then be thoroughly dried, and if, as is the case with many,
they naturally possess a good polish, they are at once fit for the
cabinet. Generally, however, it happens that when shells are dry, they
lose much of the peculiar brilliancy of hue, which they possess when seen
through the medium of the glistening water; to restore this, wash them
over with a thin solution of gum arabic, or white of egg; some collectors
use a varnish made of gum mastic, dissolved in spirits of wine; this is
perhaps preferable, as it is not affected by moisture. Many shells have
a very plain, dull, appearance, in consequence of being covered over
with a kind of skin called an epidermis, a word derived from the Greek,
and signifying the outer skin, sometimes called the cuticle. To remove
this, soak the shell in warm water for some time, and then rub it over
with a stiff brush until the covering is removed; should this be very
thick, it will be necessary to mix a little nitric acid with the water,
but this must be done very cautiously, for if too strong it will remove
all the lustre from the surface of the shell subjected to its influence.
Sometimes the file, and a substance called pumice stone has to be used,
but these are dangerous agents in inexperienced hands. The best polish
for the shell after the skin is removed, is a red earth called tripoli,
applied on a piece of soft leather.
FOSSIL SHELLS.
An eminent Geologist, named Dr. Mantell, has very beautifully and
poetically termed rocks “The Medals of Creation.” As on coins and
medals we see stamped enduring records of great historical events, so
upon the rocks are written by the finger of God, a history of some of
the mighty changes which the earth has undergone, and fossil shells are
among the plainest and most easily read of the characters or letters, in
which these truths are written. As Dr. Harvey, in his “Sea-side Book,”
observes, “Shelly-coated mollusca have existed in the waters of the sea
and in rivers, from a very early period of the world’s history, and
have left in its most stratified rocks and gravels abundance of their
shells preserved in a more perfect manner than the remains of most other
animals. Now as the species in the early rocks differ from those found
in later formations, quite as much as the latter from the mollusca of
our modern seas, the gradual change in the character of the embedded
shells marks a certain interval of time in the world’s history.” So we
see that these rocks are the leaves of a great book, written all over
with wonderful truths, and those who study such sciences as Geology and
Conchology, are enabled to read much that is there written.
Every fossil shell that such a student picks out of the chalk, or
limestone, is like a letter in the Alphabet of Creation; it has a
significance, or meaning, and a number of such put together, form as
it were, words and sentences, that can be made up into chapters, full
of instruction, aye, and of amusement too. The study may seem a little
dry at first, but never mind, go on, and you will soon be rewarded for
your diligence, by the wonders that will unfold themselves to your
understanding—the fresh and delightful views which you will obtain into
the wide universe, the new and enlarged ideas of the wisdom and goodness
of the Creator, and of the formation, habits, and connexion each with
each of his various creatures.
Properly to treat of fossil shells, would require a book of itself, and a
large book too; we can here but allude to the subject, as a part, and a
very important and interesting part of the study of Conchology; more will
be said about it in a volume which we purpose writing for this series, on
Rocks, and the petrified organic remains found in and about them.
“Those relics of an older world, which tell
Of changes slow or sudden, that have past
Over the face of nature; fossil shell,
Shark’s tooth, and bone of megatheran vast,
Turned into stone, and so preserved to show
Man of those things whereof he ought to know.”
BEAUTIFUL SHELLS.
UNIVALVES.
Gasteropoda is a name given by some naturalists to a very extensive
group of molluscous animals; the term is derived from two Greek words,
signifying stomach and foot;—it has reference to the kind of fleshy
foot which generally occupies the whole under side of the body, and by
the contraction and extension of the muscles of which, the creature is
enabled to glide, with a slow but steady motion, from place to place.
The Slug and the Snail are the commonest examples which can be adduced
of _gasteropods_; and one may tell by their slimy tracks, shining like
silver in the morning sunshine, that during the night, which is their
principal feeding time, they manage to get over a considerable extent of
ground, although “a snail’s gallop” is a proverbial expression for slow
motion; but it is astonishing how much work of any kind may be done if
one “keeps at it;” by doing this the Tortoise beat the Hare, illustrating
the truth of the proverb, that “slow and sure wins the race.” If you
watch a Snail travelling with its house upon its back, it does not seem
to make much way, and you are inclined to think that it will be long ere
it reaches the new settlement to which it appears journeying with bag
and baggage; but leave the spot for a while, and the chances are that on
your return, the “slow coach” will have got somewhere out of sight. Here
is a lesson for boys and girls; whatever you take in hand, don’t be in a
hurry, and if people say you are “slow,” think of the snail, and keep on!
[Illustration]
This, then, is a shelled mollusk of the third class, called
_Gasteropoda_, according to the system of the French naturalist Cuvier.
It has a distinct head, which, like the hinder part of the body, which
we may call a tail if we like, projects, when the creature is in motion,
considerably from the shell; it is also furnished with what we commonly
call horns, naturalists say _tentacles_, from the Latin _tento_—trying,
or essaying; with these the creature, as it were, feels its way; being
extremely sensitive; they answer the purpose of organs both of sight and
touch; put your finger slowly towards one of them, and you will observe
that, even before contact, it begins to retract, or draw in, as though
sensible of the approach of some opposing body, as it no doubt is. These
horns of the snail, then, are its feelers—eyes to the blind, fingers
to the fingerless; so God provides for his creatures all that may be
necessary for their existence, and compensates for the deprivation of one
sense or organ, by some admirable contrivance which meets the necessities
of the case.[1]
[1] It appears likely that the little knobs at the end of the snail’s
feelers, are, as some naturalists assert, in reality eyes; if so, we
were wrong in calling the creature blind. Yet is their position and
construction so different from organs of sight generally, that they serve
rather to strengthen than invalidate the above observations. The number
of the horns varies in different kinds of snails from two to six, and
some have none at all. These tentacles, when present, are always situated
above the mouth; some of them have the knobs at the base, others at the
sides; and it has been conjectured that they may be organs of smell, as
well as of sight and touch.
THE COMMON SNAIL
Is called by naturalists _Helix aspersa_, the generic name being
derived from a Greek word signifying spiral, and having reference to
the shape of the shell; the plural is _Helices_, a term applied to all
convoluted or twisted shells, which terminate in a point like a church
spire: a spiral-shelled fossil is called a _helicate_. The specific
name comes from the Latin _asper_—rough, whence also our English word
_asperity_—roughness, and several others. The _Helicidæ_, or _Helix_
family, is that which includes the land shell Snails and the naked Slugs,
and in this family there are several genera; they are distinguished from
the shelled water Snails, both sea and river, by having a different
breathing apparatus, and some other points of internal construction which
it is not necessary to describe here.
The Common Snail has a mouth, of which it makes good use, as market
gardeners well know, and yet this mouth is not furnished with teeth;
instead of these, the upper lip, which is of a horny texture, is what
is called _dentated_, from the Latin _dentus_—a tooth, that is, divided
or separated, so as to present somewhat the appearance of a row of
teeth in the jaw; this lip is of an arched form, and appears to be a
very serviceable kind of instrument to Mr. _Helix aspersa_, who, if
his character be not _aspersed_, is very destructive to all sorts of
greenery. The lower lip is divided only in the middle, where there is an
opening of some width: it is not horny, like the upper one.
Snails lay eggs, which are about the size of very small peas; they are
soft, and of a whitish colour. Being semi, that is, half, transparent, or
clear, their contents can be partly seen; and in those of a water Snail,
deposited against the side of a glass bottle, the young were detected
with partially formed shells upon their backs.
To shew how tenacious they are of life, it has been mentioned that Mr.
S. Simon, a Dublin merchant, had a collection of fossils and other
curiosities left him by his father; among these were some shells
of Snails, and _fifteen years_ after the collection came into his
possession, his son had the shells to play with, and placed them in a
basin of water, when lo! out came the slimy bodies and knobbed horns of
several of the _Gasteropods_, no doubt hungry enough after their long
sleep.
We all know that our Common Snails hybernate, or sleep through the
winter. As soon as the chills of autumn are felt, they seek out some snug
crevice in an old wall, or burrow in the earth, or congregate beneath
garden pots, roots of trees, thatched roofs, or in any hole or corner
that may be convenient, and then throwing a kind of temporary skin, like
a drum head, which naturalists call _operculum_, over the opening of
their shells, and sticking themselves fast to the sides of their refuge,
or to each other, they sleep away, careless of frosts and tempests.
A moist and rather warm state of the atmosphere seems most congenial to
the land Snails, some species of which are found in all countries, except
those where the most intense cold prevails. Generally speaking, they
do not like dry heat, and to escape from it will get under stones, and
into other cool places, from whence a shower brings them forth in such
numbers, the smaller species especially, as to lead to the popular belief
that it sometimes rains Snails.
These _Gasteropods_, although extremely injurious to vegetation, must
not be regarded as worse than useless, as they commonly are; besides
furnishing food for several wild, as well as domesticated, birds, they
are no doubt a nourishing article of diet for man. The Romans had their
_cochlearia_, where Snails were regularly fed and fattened for the table;
and the French at the present day their _escargotoires_, or Snailery, for
the same purpose; some of the Snails so kept, attain an immense size, as
well they may if fed, as by the Romans, on new wine and meal. Many poor
persons, especially those who are consumptive, might no doubt derive much
cheap sustenance and benefit from using the larger species of _Helicidæ_,
which might be collected from hedges and gardens as food. Why should they
not eat those as well as the marine mollusks, such as Oysters, Cockles,
Whelks, etc.
Snails have an extraordinary power of re-producing any part which may be
injured or cut off, even to the extent of the whole head, as has been
observed to be the case; the reparation of injury done to the shell
they can effect easily, as can all testaceous mollusks. Respecting the
construction of the shell it may be observed that it is produced in the
thickness of the mantle, or cloak-like covering which envelopes the body
of the animal; the formation commences at the small end or spire, and
gradually goes on, whorl upon whorl, as the still widening circles which
give the ridgy appearance to most univalves, are called. _Columella_,
or _pillar_, is the name given to the spire on which the cones are
rolled; this is sometimes solid, and sometimes hollow; when the latter,
the open end is called the _Umbilicus_, meaning the navel or centre.
The opening at the bottom, from which the animal issues, is the last
portion finished, and this is called the _aperture_, a Latin word adopted
into the English dictionary. Some of these _Helices_ are wide and flat,
even hollow and cup-like, with the whorls rising above the pillar—these
are called _discoid_ shells; others which are long and narrow, with
projecting spires, are termed _turbinated_ shells; the former being
more or less flat or disk-like, the latter twisted, whirling, like a
spinning-top, from the Latin _turbo_—a whirling, a turning round.
[Illustration: DISCOID.]
[Illustration: TURBINATED.]
If we take a Common Snail, and plunge it into boiling water, which will
instantly kill it, so that it can be removed from the shell, we shall
find the whole of that part of the body which was lodged in the upper
whorls, or spiral part of the shell, is covered with a thin membrane
or skin; this is called the _mantle_, and that portion of it which
corresponds with what we may consider as the back of the mollusk, and
which is considerably thickened, is termed the _collar_; here are
situated the glands, which secrete the colouring and other matter of
which the shell is mainly composed; although the substance called nacre,
or mother-of-pearl, is secreted in the thinner part of the mantle; it
is however from the collar that the growth or increase of the shell
proceeds. It is in accordance with certain variations in the shape and
disposition of this mantle and collar, that shells assume such very
different shapes. Sometimes the whorls or spiral ridges, are projected or
thrown far out, and this produces the _turbinated_ shell. Sometimes they
scarcely rise above each other, but rather spread towards the sides, and
then we have the _discoid_ shape. Generally speaking, the whorls of a
shell take a direction from left to right, but occasionally an opposite
one; they are then called sinistral, or left-handed shells: such are
not common. If one of the twisted shells be divided length-ways, it will
be seen that the inside of the whorls wind in an ascending direction,
round the _Columella_, or central column, as the spiral staircases in the
Crystal Palace.
But let us return to our Garden Snail, who has many near relatives in
Britain, several of which have beautifully-marked and convoluted shells,
as will be seen by a reference to our coloured illustrations, Plate I.
We will introduce them in due order. Fig. 1, the Banded Snail, (_Helix
nemoralis_,) from the Latin _nemus_—a wood or grove; the prettily-striped
shells of this species may be found in great plenty among the roots and
in the crevices of the rugged boles of old forest trees, as well as in
hedge-rows and in mossy banks, and other situations near woods. Fig. 2,
the Heath Snail, (_H. ericetorum_,) from _erica_, the Latin for heath;
a small species with brown bands, remarkable for its large _umbilicus_,
perforating the centre of the shell nearly through. Fig. 3, the Silky
Snail, (_H. sericea_,) from the Latin _sericus_—silk-like; the shell
of this species is covered with short slimy hairs, which give it a
glistening appearance. Fig. 4, the Stone Snail, (_H. lapicida_,) from
the Latin _lapis_—a stone: Linnæus called the species the Stone Cutter,
probably on account of its habit of frequenting stony places, and the
peculiar construction of the shell, which has a sharp edge running round
each whorl; it is commonly found lodged in the cavities of loose-lying
stones, but which it can scarcely be suspected of having hollowed out for
its own accommodation.