Color in Shells

Shells are the hard coverings of a species of mollusca, a division of the animal kingdom, whose name is derived from mollis, soft, meaning soft-bodied animals. Mollusca bear the general name of shell-fish, though they do not embrace all that is included in that title. The shell is formed by the animal himself, from carbonate of lime and gelatine; these substances are stored in glands in his body. The coloring matter exudes from the pores of the mantle or thick skin which encloses the mollusca; it penetrates the shell before it is hardened, and the colors arranged in order give the shell the peculiar markings which belong to different species. When an accident happens to a shell the animal is able to repair it, using the process by which he first made it. He can also enlarge his abode, when needed, in the same manner, the additions often being plainly indicated by longitudinal sutures, or seams. This is the case in Buccinum Harpa, the harp shell. Another species, the music shell, has lines corresponding to the staff in music, upon which are spots resembling the notes.

Among bivalve shells, the Giant Clam (Chama Gigas) is a specimen of unusual magnitude. One of these shells, described by Linnaeus, weighed four hundred and ninety-eight pounds, and he says that its inhabitant furnished one hundred and twenty men with a day's food. A specimen of this extraordinary species formed a very elegant baptismal font in the Church of St. Sulpice, in Paris; it was presented by the Venetians to Francis I. Pearls, the effect of disease in certain Mollusca, are among the most costly ornaments of the wealthy. The study of shells, called Conchology, was at one time a very fashionable pursuit, and during that period enormous prices were paid for some particular shell. A Carinaria shell which once sold for five hundred dollars is now worth twenty cents. In 1701 a wentle trap sold for two hundred dollars; it is now worth one dollar. The golden cypraea was formerly the badge of royalty in the Hawaiian Islands. Whoever picked up one of these insignia and did not carry it to the king, was held guilty of high treason. The prices of other shells have varied in like manner. The substitution of Zoology for Conchology, or the study of the animal producing and living in the shell instead of the mere shell-fancying of former days, together with the frequency of remote voyages, has made shells more common and has wrought the great change in the value of these articles. Many shells are intrinsically beautiful and will always be objects of interest and value to those curious in the pursuit of knowledge, and it is to be deeply regretted that Conchology is no longer made a separate and special study.

One of the most beautiful substances in nature is the shell-opal, formed by the ammonite. The forms and colors of shells answer some particular purpose, or obey some particular law, and are therefore worthy of our special attention.

The tints of many shells are not visible until brought to light by the processes of the shell fanciers, and the "pearly hall of the nautilus" is not seen until the life that gave it birth has passed away. "Out with your shells," meaning "out with your money," is an allusion to the Cypraea moneta (money cowry) used in Southern Asia, and on the coast of Guinea in Africa, for money. In the Philippine Islands, other shells are used for coins. Ostracism was introduced into Athens by Clisthenes. The system was, in brief, banishment, by popular vote, of any citizen who might be considered dangerous to the state. The method was that any citizen, without making a definite charge, might vote for the banishment of another by simply writing the name of the person to be banished on an ostracon, or oyster shell, and dropping it into an urn. If, when the shells were counted, it was found that six thousand votes had been cast against any one person, that person was banished from the state for ten years. He was allowed no trial and no opportunity for defence. The story of the Ostracism of Aristides, the Just, is too familiar to bear repetition here.