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and direction to the bands observable in the self; the colouring matter appearing to be sposed, ready for its deposition with the bstances of the shell. But in the olives and cellaneous shells the colours are disposed in ers, the outer of which is the production of an zation different from that of any of the other ants of shells, and from which proceeds an on also different from what occurs in any nstance. The highly ornamented surface of shells is formed at two different periods, and o different processes. The first appears to be eposition which takes place from the surface body of the animal, and in which but little place different from what occurs in shells in l. But as the age of the animal advances, urface is covered by another; the primitive rs disappear, others are disposed over them, he substance itself of the shell becomes conbly thickened. This process is performed by ple but most curious organization. Two soft oraneous flaps, or winged processes, pass out opening of the shell, turn back on the external ex surface, and cover it so completely as not ave the least portion to be seen at the line where meet each other, on the back of the shell. From superior surface of these membraneous bodies, surface which clings to the convex part of the exudes that secretion by which the shell is cased in bulk, and a new arrangement of the tiful colours of its drapery is effected. Brure ascertained this formation of a second surface ctual observation at Madagascar; and the fact ves additional proof from the pale line which ses frequently along the back of these shells, king the part where the edges of the membraneous gs met. Still more positive proof is rendered rubbing down the second coat, when the markings the first coat will make their appearance.

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Although the colours are thus disposed by th animal, the action of light appears to have a ma terial effect in augmenting their brilliancy; cli mate also occasions considerable differences in thi respect; hence the shells obtained from the torri zones are much more rich in their colouring tha those which are found in the more temperate zones But notwithstanding the circumstance just noticed there is great reason for attributing the high degree o colouring in shells more to the effects of light tha to the heat of the climate. It is not the colourin only of the second coat of the porcellaneous shell which is given by this second operation; the sever asperities observable in various shells, as in th cypræa tuberculosa, and in the c. pediculus, are s peradded at the same period.

On Taking and Preserving
Shells.

On taking a shell, the most expeditious method depriving the animal of life, is to immerse it in spi of wine: this being effected, the shell, with its co tents, may be placed in hot water for some tim by which the body of the animal will become fir and may easily be removed with any sharp instr ment. Care should be taken that the whole of t animal be extracted, as, if any parts be left within t shell, on their becoming putrid, they often give o a stain which is injurious to the markings of the shel If any difficulty be experienced in removing t whole of the body, burying the shell for some hou in an ant-hill will generally answer the purpose mo effectually, as these little animals will consume eve fleshy particle.

Of multivalve and bivalve shells, the differe parts of the shell should all be carefully preserve in these no difficulty will arise in removing the

- as almost instantly the animal is dead the -en, and their contents are easily extracted. atest attention should be observed not to ther the hinge or teeth, as, from the structure parts, the generic characters are principally ; care should likewise be taken to preserve rd or silky threads that may be attached, as H often assist in making out the species. - brief sketch we have given of the habits of aus, their haunts are mostly alluded to: some to be obtained accidentally, when detached cks situated beneath the depths of the ocean; re found in rocky currents, or in shallows of ive fathoms depth; many resort to the sands on the beach, beneath the surface of which ire as the water recedes; and numerous kinds found attached to sub-marine rocks. Most re but of little worth, after being exposed on ch to the sun and air; so that, to have them in ion, they should, if practicable, be obtained eir inhabitant alive. A trawling or dredge net, s in common use with fishermen, will be found seful, as by it many kinds can be obtained eep water, which would otherwise only come ntally to shore.

y valuable shells may be found on the beach iolent storms, being removed or separated eir native beds by the agitations of the water: kinds may be found affixed to the bottoms of hat have been long stationed in warm climates, o the stocks of anchors, cables, &c.

obtaining any species containing the living 1, the particular genus to which the animal gs should be noted, with its peculiarities of ure, as likewise whether frequenting deep washallows; if affixed to other substances, or ed; if it retires beneath the sand or slime e beach at low water, and such particulars; the animal advances in age, any and what

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changes take place in the appearance or structure o its dwelling; if it be used as food, or afford any dye and if the shell or shells be convertible to domesti or other purposes.

River shells, though not of such brilliant colours often possess much interest: their localities are of th same kind as the marine species, and the same mean are required to obtain them. Their substance usually thin, and they are very brittle.

Land shells are frequently of very beautiful c lours, and are held in great estimation; they freque moist mossy banks, shady lanes, and some of th kinds are only found on chalky situations. The te restrial shells, or rather their inhabitants, have th property of resisting the action of boiling water for considerable length of time, without receiving ar material injury; so that the quickest mode of destro ing the animals is by plunging them into spirit, eith of wine or turpentine: the substance of land shells thin, and they are mostly brittle..

When the shells are clean, dry, and their conten completely removed, they should be wrapped s parately in paper, and may then be packed in a bo with a quantity of sawdust, bran, or fine sand, that all the interstices between the shells be filled to prevent their rubbing one against the other; b sides this precaution, they require no other care'.

On Polishing Shells.

Amateurs are seldom contented with the simplici of nature. Vitiated in their taste by a fashion whi abides by no rules, they attempt to improve ev her most elegant productions, and delight to exhi in their cabinets some of the efforts of their art. such are in search of innocent amusement, we me not to dispute the propriety of their conduct, b

Graves's Naturalist's Pocket Book n 679

shortly to mention, for their edification, the generally in use to improve the beauty aceous objects Many shells, it is true, ly possess so fine a polish, that no preparaconsidered necessary before placing them in binet. Such are the cypreæ, olive, and the number of what are termed porcellaneous In general, however, it happens that, when become dry, they lose much of their natural This may be very easily restored, by washing with a little water in which a small portion of rabic has been dissolved, or with the white of

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This is the simplest of those processes are employed, and is used not only by the collector, but by the scientific Conchologist. are many shells of a very plain appearance, outside, by reason of a dull epidermis or skin which they are covered: this is removed by g the shell in warm water, and then rubbing it th a brush. When the epidermis is thick, it is sary to mix with the water a small portion of acid, which, by dissolving a part of the shell, ys the cohesion of the epidermis. This last must be employed with great caution, as it ves the lustre from all the parts exposed to its nce. The new surface must be polished with er, assisted by tripoli. But, in many cases, these methods are ineffectual, and the file and pumice-stone must be resorted to, in order to off the coarse external layers, that the concealed ties may be disclosed. Much address and exence are necessary in the successful employment is last process. But it must be confessed that eward is often great. When thus prepared, even common muscle is most beautiful.

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