Sea-Weeds, Shells and Fossils Part 2

HOW TO MAKE A CABINET.

It is a common mistake, both with old and young, to imagine that a handsome cabinet is, in the first instance, a necessity; but no greater blunder can be made: the cabinet should be considered merely an accessory, the collection itself being just as valuable, and generally more useful, when kept in a series of plain wooden or cardboard boxes. We intend, therefore, to describe the simplest possible means of keeping a collection of sh.e.l.ls, leaving elaborate and costly methods to those who value the case more than its contents.

The first thing required is some method of keeping the different species of sh.e.l.ls apart, so that they may not get mixed, or be difficult to find when wanted. The simplest plan of doing this is to collect all the empty chip match-boxes you can find, throw away the cases in which they slide, and keep the trays, trying to get as many of a size as possible. (The ordinary Bryant & May's, or Bell & Black's, are the most useful, and with them the trays of the small Swedish match-boxes, two of which, placed side by side, occupy nearly exactly the same s.p.a.ce as one and a half of the larger size, and so fit in with them nicely.) In these trays your sh.e.l.ls should be placed, one kind in each tray; but although very convenient for most specimens, they will of course be too small for very many, and so the larger trays must be made. This may easily be done as follows: cut a rectangular piece of cardboard two inches longer one way than the length of the match-tray, and two inches more the other way than twice the width of the match-tray; then with a pencil rule lines one inch from the edges and parallel with them (Fig. 1); next cut out the little squares (_a_ _a_, _a_ _a_) these lines form in the corners of the piece of cardboard, and then with a penknife cut _half_ through the card, exactly on the remaining pencil-lines, and bend up the pieces, which will then form sides for your tray; and by binding it round with a piece of blue paper, you will have one that will look neat, uniform with the others, and yet be just twice their size. If required, you can make in the same way any size, only take care that they are all multiples of one standard size, as loss of s.p.a.ce will thereby be avoided when you come to the next process in your cabinet. This is, to get a large box or tray in which to hold your smaller ones.

[Ill.u.s.tration: Fig. 1. How to cut a cardboard tray.]

+---+-----------+---+ _a_ _a_ +---+-----------+---+ +---+-----------+---+ _a_ _a_ +---+-----------+---+

The simplest plan is to get some half-dozen cardboard boxes (such as may be obtained for the asking or for a very trifling cost at any draper's), having a depth of from one to two inches (according to the size of your sh.e.l.ls); in these your trays may be arranged in columns, and the boxes can be kept one above the other in a cupboard or in a larger box. More boxes and trays can, from time to time, be added as occasion requires, and thus the whole collection may be kept in good working order at a trifling cost. A more durable form of cheap cabinet may be made by collecting the wooden boxes so common in grocers'

shops, cleaning them with sand-paper, staining and varnis.h.i.+ng them outside, and lining them inside with paper; or, if handy at carpentering, you may make all your boxes, or even a real cabinet, for yourself.

HOW TO COLLECT Sh.e.l.lS.

Provision being thus made for the comfortable accommodation of your treasures, the next consideration is, how to set about collecting them. Mollusca are to be found all over the globe, from the frozen north to the sun-baked tropics, on the land or in lakes, rivers, or seas--wherever, in fact, they can find the food and other conditions suitable for their growth and development; but the collector who is not also a great traveller, must of course rely for his foreign specimens upon the generosity of friends, or else procure them from dealers. In most districts of our own country, there are, however, to be found large numbers of sh.e.l.ls whose variety and beauty will astonish and reward the efforts of any patient seeker. Begin with your own garden,--search in the out-of-the-way, and especially damp, corners; turn over the flower-pots and stones which have lain longest in one place, search amongst the roots of the gra.s.s growing under walls, and in the moss round the roots of the trees, and you will be surprised at the number of different sh.e.l.ls you may find in a very short s.p.a.ce of time. When the resources of the garden have been exhausted, go into the nearest lanes and again search the gra.s.s and at the roots of plants, especially the nettles which grow beside ditches and in damp places; hunt amongst the dead leaves in plantations, and literally leave no stone unturned. All the apparatus it is necessary to take on these excursions consists of a few small match or pill-boxes in which to carry home the specimens; a pair of forceps to pick up the smaller ones, or to get them out of cracks; a hooked stick to beat down and pull away the nettles; and, above all, sharp eyes trained to powers of observation. The best time to go out, is just after a warm shower, when all the gra.s.s and leaves are still wet, for the land-snails are very fond of moisture, and the shower entices them out of their lurking-places. Where the ground is made of chalk or limestone, they will be found most abundant; for as the snail's sh.e.l.l is composed of layers of animal tissue, strengthened by depositions of calcareous earthy-matter which the creature gets from the plants on which it feeds, and these in their turn obtain from the soil--it naturally follows that the snail prefers to dwell where that article is most abundant, as an hour's hunt on any chalk-down will soon show.

When garden and lanes are both exhausted, you may then turn to the ponds and streams in the neighbourhood, where you will find several new kinds. Some will be crawling up the rushes near the margin of the water, others will be found in the water near the bank, while others may be obtained by pulling on sh.o.r.e pieces of wood and branches that may be floating in the water; but the best are sure to be beyond the reach of arm or stick, and it will be necessary to employ a net, which may be easily made by bending a piece of wire into a circle of about four inches in diameter, and sewing to it a small gauze bag; it may be mounted either on a long bamboo, or, better still, on one of those ingenious j.a.panese walking-stick fis.h.i.+ng-rods. For heavier work, however, such as getting fresh-water mussels and other mollusca from the bottom, you will require a net something like the accompanying figure (Fig. 2), about one foot in diameter. This, when attached to a long rope, may be thrown out some distance and dragged through the water-weeds to the sh.o.r.e, or if made with a square instead of a circular mouth, it may be so weighted that it will sink to the bottom, and be used as a dredge for catching the mussels which live half-buried in the mud. To carry the water-snails home, you will find it necessary to have tin boxes (empty mustard-tins are the best), as match-boxes come to pieces when wetted.

[Ill.u.s.tration: Fig. 2. Net for taking water-snails.]

The finest collections of sh.e.l.ls, however, are to be made at the sea-side, for the marine mollusca are both more varied in kind and more abundant than the land and fresh-water ones, and quite an extensive collection may be made in the course of an afternoon's ramble along the sh.o.r.e; it is necessary, however, to carefully reject such specimens as are worn by having been rolled by the waves upon the beach, as they are not of any great value in a collection; it is better, in fact, if possible, to go down to the rocks at low water and collect the living specimens. Search well about and under the sea-weeds, and in the rock-pools, and, when boating, throw your dredge-net out and tow it behind, hauling it in occasionally to see what you have caught, and to empty the stones and rubbish out.

At low tide also, look out for rocks with a number of round holes in them, all close together, for in these holes the Pholas (Fig. 22) dwells, having bored a burrow in the solid rock, though _how_ he does it we do not yet quite know.

The Razor-sh.e.l.ls and c.o.c.kles live in the sand, their presence being indicated by a small round hole; but they bury themselves so fast that you will find it difficult to get at them. Some good specimens, too, of the deeper water forms are sure to be found near the spots where fishermen drag their boats ash.o.r.e, as they are often thrown away in clearing out the nets; moreover, if you can make friends with any of the said fishermen, they will be able to find and bring you many nice specimens from time to time.

The reason that so much has been said about collecting living specimens, is not only because in them the sh.e.l.l is more likely to be perfect, but also because in its living state the sh.e.l.l is coated with a layer of animal matter, sometimes thin and transparent, at others thick and opaque, called the _periostrac.u.m_ (or _epidermis_), which serves to protect the sh.e.l.l from the weather, but which perishes with the animal, so that dead sh.e.l.ls which have lain for some time tenantless on the ground, or at the bottom of the water, exposed to the destructive agencies that are constantly at work in nature, have almost invariably lost both their natural polish and their varied hues, and are besides only too often broken as well. Since, however, even a damaged specimen is better than none at all, such should always be kept until a more perfect example can be obtained.

HOW TO PREPARE THE Sh.e.l.lS FOR THE CABINET.

The question with which we have next to deal is, after collecting a number of living mollusks, how, in the quickest and most painless manner possible, to kill the animals in order to obtain possession of their sh.e.l.ls. There is but one way we know of in which this may be accomplished, and that is by placing the creatures in an earthen jar and pouring _boiling_ water on them. With land, or fresh-water snails, the addition of a large spoonful of table-salt is advisable, as it acts upon them chemically, and not only puts them sooner out of pain, but also renders their subsequent extraction far easier. Death by this process is instantaneous, and consequently painless; but to leave snails in cold salt water is to inflict on them the tortures of a lingering death; while for the brutality of gardeners and other thoughtless persons who seek to destroy the poor snail they find eating their plants by crus.h.i.+ng it under foot on the gravel path, no words of condemnation are too strong, since it must always be borne in mind that snails have not, like us, _one_ nervous centre, but three, and are far more tenacious of life; hence, unless all the nerves are destroyed at once, a great deal of suffering is entailed on the poor creature; and if merely crushed under foot, the mangled portions _will live for hours_. Hot water has also the advantage of tending to remove the dirt which is almost sure to have gathered on the sh.e.l.ls, and so helping to prepare them better for the cabinet. As soon as the water is cool enough, fish out the sh.e.l.ls one by one and proceed to extract the dead animals. This, if the mollusk is _univalve_ (_i.e._, whose sh.e.l.l is composed of a single piece), such as an ordinary garden snail, can easily be done by picking them out with a pin; you will find, probably, that some of the smaller ones have shrunk back so far into their sh.e.l.ls as to be beyond the reach of a straight pin, so it will be necessary to bend the pin with a pair of pliers, or, if none are at hand, a key will answer the purpose if the pin be put into one of the notches and bent over the edge until sufficiently curved to reach up the sh.e.l.l. You will find it convenient to keep a set of pins bent to different curves, to which you may fit handles by cutting off the heads and sticking them into match stems. It is a good plan to soak some of the smaller snails in clean cold water before killing them, as they swell out with the water, and do not, when dead, retreat so far into their sh.e.l.ls. If you have a microscope, and wish to keep the animals till you have time to get the tongues out, drop the bodies into small bottles of methylated spirit and water, when they will keep till required, otherwise they should of course be thrown away at once.

The now empty sh.e.l.ls should be washed in clean warm water, and, if very dirty, gently scrubbed with a soft nail or tooth brush, and then carefully dried.

In such sh.e.l.ls as the Periwinkle, Whelk, etc., whose inhabitants close the entrance of their dwelling with a trap-door, or _operculum_ as it is called, you should be careful to preserve each with its proper sh.e.l.l.

If you are cleaning _bivalves_, or sh.e.l.ls composed of two pieces, like the common mussel, you will have to remove the animal with a penknife, and while leaving the inside quite clean, be very careful not to break the ligament which serves as a hinge; then wash as before, and tie them together to prevent their gaping open when dry.

Sometimes the fresh-water or marine sh.e.l.ls are so coated over with a vegetable growth that no scrubbing with water alone will remove it, and in these cases a weak solution of caustic soda may be used, but very carefully, since, if too strong a solution be employed, the surface of the sh.e.l.l will be removed with the dirt, and the specimen spoilt. In some sh.e.l.ls the periostrac.u.m is very thick and coa.r.s.e, and must be removed before the sh.e.l.l itself can be seen; but it is always well to keep at least one specimen in its rough state as an example.

In other sh.e.l.ls the periostrac.u.m is covered over with very fine, delicate hairs (_Helix sericea_ and _Helix hispida_, Fig. 3), and great care must then be taken not to brush these off.

[Ill.u.s.tration: Fig. 3. (_a_) _Helix sericea_ and (_b_) _Helix hispida_.]

HOW TO MOUNT THE Sh.e.l.lS FOR THE CABINET.

When the specimens are thoroughly cleaned, the next process is to sort out the different kinds, placing each description in a different tray, and then to get them ready for mounting, for no collection will look well unless each kind is so arranged that it may be seen to the best advantage, and is also carefully named. Where you have a good number, pick out first the largest specimens of their kind, then the smallest, then a series, as you have room for them, of the most perfect; and finally those which show any peculiarity of structure or marking. Try, too, to get young forms as well as adult, for the young are often very different in appearance from the full-grown sh.e.l.l. Mark on them, especially on such as you have found yourself, the locality they came from, as it is very important to the sh.e.l.l collector to know this, since specimens common enough in one district are often rare in another. Either write the name of the place in ink on a corner of the sh.e.l.l itself, or gum a small label just inside it, or simply number it, and write the name of the place with a corresponding number against it in a book kept for the purpose. Next select a tray large enough to hold all you have of this kind; place a piece of cotton wool at the bottom, and lay your sh.e.l.ls upon it. For small sh.e.l.ls, however, this method is not suitable, as the cotton wool acts on them like a spring mattress, and they are liable on the least shock to be jerked out of their trays and lost. This difficulty may be met by cutting a piece of cardboard so that it just fits into your tray, and then gumming the sh.e.l.ls on to it in rows; but remember that, in this plan of mounting, it is impossible to take the sh.e.l.ls up and examine them on all sides as you do the loose ones, and so you must mount a good many, and place them in many different positions, so that they may be seen from as many points of view as possible. The gum used should always have nearly one-sixth of its bulk of pure glycerine added to it; this prevents it from becoming brittle when dry, otherwise your specimens would be liable after a time to break away from the card and get lost. If the sh.e.l.ls will not stay in the position you require, wedge them up with little pieces of cork until the gum is dry.

When the sh.e.l.ls are mounted, you must try, if you have not already done so, to get the proper names for them; it is as important to be able to call sh.e.l.ls by their right names as it is to know people by theirs. The commoner sorts you will be able to name from the figures of them given in text-books, such as those quoted in the list at the end of this little work; but some you will find it very difficult to name, and it will then be necessary to ask friends who have collections to help you, or to take them to some museum and compare them with the named specimens there exhibited. When the right name is discovered, your label must then be written in a very small, neat hand, and gummed to the edge of the tray or on the card if your specimens are mounted. At the top you put the Latin name, ruling a line underneath it, and then, if you like, add the English name; next, put the name of the place and the date at which it was found, thus:--

===================================== Helix aspersa (Common snail), ----------------------------- Lane near Hampstead Heath, July 10th, 1882.

A double red ink line ruled at the top and bottom will add a finished appearance to it.

HOW TO CLa.s.sIFY THE Sh.e.l.lS FOR THE CABINET.

All the foregoing processes, except the naming of your specimens, are more or less mechanical, and are only the means to the end--a properly arranged collection. For, however well a collection may be mounted, it is practically useless if the different sh.e.l.ls composing it be not properly cla.s.sified. By cla.s.sification is meant the bringing together those kinds that most resemble each other, first of all into large groups having special characteristics in common, and then by subdividing these into other smaller groups, and so on. Thus the animal kingdom is divided, first of all, into _Sub-kingdoms_, then each _Sub-kingdom_ into so many _Cla.s.ses_ containing those which have further characteristics in common, the _Cla.s.ses_ into _Orders_, the _Orders_ into _Families_, the _Families_ into _Genera_, and these again into species or kinds.

The Mollusca, or soft-bodied animals, of whose protecting sh.e.l.ls your collection consists, form a sub-kingdom, and are subdivided into four cla.s.ses:--

1. Cephalopoda.

2. Gasteropoda.

3. Pteropoda.

4. Lamellibranchiata (or Conchifera).

And these again into Families, Genera, and Species.

The s.p.a.ce at our disposal being limited, it is impossible to do more than furnish some general outlines of the different forms. For further details it will be necessary to refer to one of the larger works, a list of which will be found on the last page.

[Ill.u.s.tration: Fig. 4. _Argonauta Argo._]

[Ill.u.s.tration: Fig. 5. "Bone" of _Sepia officinalis_.]

CLa.s.s I.--The CEPHALOPODA (Head-footed) contains those mollusca that, like the common Octopus, have a number of feet (or arms) set round the mouth, and is divided into those having two gills. (Order I.

Dibranchiata); and those with four (Order II. Tetrabranchiata). Order I. is again divided into: (_a._) Those with _eight_ feet like the Argonaut (or Paper-nautilus, Fig. 4), which fable has so long endowed with the power of sailing on the surface of the ocean, (it is even represented in one book as propelling itself through the air!) and the common Octopus. (_b._) Those with _ten_ feet, such as the Loligo (or Squid, Fig. 6), whose delicate internal sh.e.l.l so much resembles a pen in shape; the Cuttle-fish (Sepia, Figs. 5 & 7), whose so-called "bone" (once largely used as an ink eraser) is frequently found on our southern coasts; and the pretty little _Spirula_ (Fig. 8).

[Ill.u.s.tration: Fig. 6. _Loligo vulgaris_, and "Pen."]

[Ill.u.s.tration: Fig. 7. _Sepia officinalis._]

The only representative of the four-gilled order now living is the well-known Pearly Nautilus; but in former times the Tetrabranchiata were extremely numerous, especially the _Ammonites_.