Pearl oyster

“ There are many theories as to the causation of pearls in the pearl shell; the most common is the particularly idiotic one of a grain of sand, or other foreign body, inserting itself within the shell and setting up an irritation which causes the oyster to build round the intruder a smooth coat of pearly matter. This theory is senseless on the face of it. From its natural habitat every pearl oyster must have thousands of grains of sand or other bodies lodged against its lips in each tide. ”

“ Although the quickest way of dealing with oysters in the mass is by rotting them, the search for pearls can be conducted on oysters fresh from the sea, and Floyd, as he sat on the raft, amused himself by opening some of the shells with his pocketknife, choosing the largest for this purpose. He found no pearls, but plenty of surprises. Nearly every large oyster in the southern seas gives shelter to a "messmate." A little crab, a small lobster, a worm, or a shrimp, lives in the shell along with the host. ”

“ Finally there is no reason for any despondency in regard to the future of the pearl oyster fisheries, if they are treated scientifically. The adult oysters are plentiful on some of the paars and seem for the most part healthy and vigorous; while young oysters in their first year, and masses of minute spat just deposited, are very abundant in many places. ”

“ They are found in various parts of the world; but the best pearls have always come from the East: they are valuable in proportion as they possess that peculiar lustre known as 'water,' which it is impossible to describe in words. There are several varieties of the pearl-oyster, but the best of them is of a nearly circular form, and from four to eight inches in diameter. Here is a picture of one of these shells, with a single pearl adhering to it. The outside of the shell is rough, and has a series of ridges that extend from the valve to the edge. The young oysters rarely contain pearls ”

“ The common idea that a pearl is due to the hardening of dew, to obtain which the oyster comes to the surface of the [45] sea at night, was suggested to me by an Arab dealer, but a purely native idea is that abundance of rain in the winter will result in the appearance of many young oysters next summer. Because to themselves every drop of the scanty rainfall is precious beyond everything, they sympathetically imagine it must be of value to the oysters. However, this point, like the former on the formation of pearls, needs no great study of oyster habits to refute. ”

“ They are afraid of polyps, which are greedy for oyster meat and are always grouped about the places where they are. They are likewise afraid of other sea-monsters, and most of all they fear to suffocate if they stay too long under water. The pearl oysters in the profoundest depths of the sea consequently have time to grow, and the larger and older the shell becomes, the larger the pearls they harbour, though in number they are few. Those born at the bottom of the sea are believed to become food for the fish ”

“ They are dragged over the beds, and when filled are lifted and their contents emptied into the boat, the fishermen culling out the desirable oysters from the mass and throwing the refuse material overboard.
The pearl-oyster (Margaritifera radiata) secured on the coast of Venezuela is closely related to the Ceylon species. It averages slightly larger in size, and there is a much greater range in coloration. The pearls are of good quality. In color they range from white to bronze, and occasionally a so-called black one is found. ”

“ The pearl fishers descend six to eight fathoms forty or fifty times a day, and can remain under water from a minute to a minute and a half. So much for practice. In the course of a million or hundred million years, more or less, each successive generation pursuing this calling, under the law of inherited tendencies, these people might well return to the amphibious state and give us an illustration of evolution, backward.
The pearl oyster is a large, round bivalve, sometimes twelve inches in diameter. ”

“ But they are not very industrious, and seldom descend more than twelve or fifteen times a day, preferring rather to go with their wants half satisfied than to satiate them by more active exertions.
Many descents may be necessary to locate and obtain a single oyster, but when this is secured the shell alone may ordinarily be traded for sufficient to supply the fisherman’s needs for several days, and there is always the chance of a pearl. After a short day of labor, the fishermen return, and the oysters which they have secured are opened and examined for pearls. ”

“ The beds of the marine shell-fish from which pearls are taken lie always under water. Unlike others which are sometimes left exposed by the tides, to be gathered by man without difficulty, the pearl oyster is never left uncovered by the sea. It is found usually on shoals some distance from shore, sometimes but five to seven feet from the surface ”

“ A large pearl naturally takes many years to form inside the oyster’s shell, whilst small ones take so many years less. Even in one or two years a foreign substance, say a small shot, will, if placed in a pearl oyster, become to all appearance a pearl of high price. ”

“ RISK OF WAR "You can't get pearls from oysters till the oysters are rotten," said Schumer next morning, as they sat after breakfast consulting on the day's work. "Of course, you could take every individual fresh oyster and hunt under its beard; but you know how an oyster sticks to its shell even after it is opened, and you can fancy the work it would be. Once they are decayed they are mushy, and the work is easy though it's not pleasant. ”

“ Well, pearl oysters are about the only kind that thrive around the islands, and the common oyster of America is unknown. Pearls are plentiful, but a good many of them are worthless. In years gone by the pearl industry was monopolized by the king. ”

“ Since it is constantly wasting away on the exterior surface as it grows on the interior, it follows that in time the shell passes the pearl quite through to the outside, where it rapidly decays. Thus the oyster virtually forces the annoying intruder directly through the wall of its house instead of by way of the open door, and magically closes the breach with its marvelous masonry. ”

“ An oyster may be induced to open its shell by being held near the galley fire on the lugger, and the insertion of a piece of cork holds it open while a pearl is shaken out or hooked out by means of a piece of wire. Then the cork is removed and the oyster closes again with no evidence of robbery. The proprietors of boats who themselves open the oysters almost invariably secure larger yields of fine pearls than those who depend on paid employees, who rarely have the luck to find choice pearls, judging from what they turn in. ”

“ They rarely descend more than four fathoms, and most of the work in Tablegram Bay is in less than two fathoms. Each diver returns with from one to five or more oysters, depending on their abundance, and receives one half of the catch as his share of the proceeds. Unlike the method in the pearl-oyster fishery of Ceylon, the Placuna oysters are opened while fresh, this work being performed by coolies, who are compensated at the rate of about Rs.3 per 1000. ”

“ Sometimes one oyster will contain a dozen small pearls and even more. Such oysters are often diseased and their shells are rough, but on the other hand a perfectly healthy oyster may contain a fine round pearl of large size. Many people believe that some irritating substance is the cause of every pearl. ”

“ As a consequence, pearls are more numerous in oysters which have been long infected, where the worms are older and more liable to die. This parasitic worm has been traced from the pearl-oyster to the trigger-fishes, which eat the pearl-oysters, and thence into certain large fish-eating rays, where it becomes sexually mature and produces embryos which enter the pearl-oyster and begin a new cycle of life-phases. ”

“ Oyster-beds are generally much nearer the shore than most kinds of shells. It is said to be when an oyster gets restless or uneasy that a strange substance enters the edge of the shell, and after a time a pearl is formed. And while many pearls are found in oyster-shells, they also are often found fastened to the pink bosom of a conch-shell. ”

“ In the evenings the datu would talk over the tales they had heard from other fishermen, and the chief delighted to recount the story of the vast pearl which was seen by the men of old, and actually brought in its oyster into a canoe, but had slipped from the fingers of the incautious captor. The natives declare that the oysters containing the largest pearls are always open, until you approach them, and that by cautiously peering into the water, they may be seen. ”

“ Iron, however, exercises an electro-magnetic influence upon the composition forming the body of the bivalve, causing a sudden contraction—so that, on a knife being introduced into the shell, the latter closes in the most natural way. We manufacture pearls on the premises, and advertise that one oyster in every gross taken from our beds contains a pearl of more or less value; and there's a greater demand for our oysters than for any others in the world. Our oyster beds are way down along the coast, about ten miles off; and are inspected by thousands yearly. ”

“ The window-glass shell (Placuna placenta) , the vitre chinoise of some writers, yields a few small, irregularly shaped pearls of a dull leaden color. It occurs in the inshore waters of the Indian and the southwestern Pacific oceans; fisheries are prosecuted in Tablegram Lake, near Trincomali, on the northeast coast of Ceylon; on the coast of Borneo, especially at Pados Bay, and to a less extent in some other localities. This mollusk is quite distinct from the true pearl-oyster, and in adult life is devoid of the byssus, living on the muddy bottom of the shallow waters. ”

“ Oyster’s shell and pays no rent at all.”
“Tell me about it,” demanded the boy named Billy. “I always supposed that pearls grew at the bottom of the sea.”
“So they do,” said Somebody, “about fifteen fathoms deep is where the pearl bearing oyster lives. He is rather particular about his home and selects a place where there is a swift current of water. There he and his family lie on the hard bed of the ocean and wait for the current to bring their food. Sometimes they prefer to attach themselves to an overhanging ledge, where they live closely huddled together. ”

“ Creations similar in construction to pearls are found occasionally in the common oyster and clam. Though entirely devoid of the pearly texture and luster, some of them are very perfect in shape and smoothness of skin. Whether taken from the oyster or clam they are usually called "clam pearls." The color of the oyster pearl is generally a light drab. The clam pearls are mostly purplish red or blue, often dark enough to appear black. Those taken from the oyster are generally round; those from the clam are more frequently ovoid. ”

“ In Japan the production of these pearly formations in Margaritifera martensi, which is closely related to the Ceylon oyster, has developed into some prominence since 1890, and the results have been well advertised. The industry is located in Ago Bay, near the celebrated temple of Ise in the province of Shima, and gives employment to about one hundred persons. It is stated that the proprietor, Kokichi Mikimoto, has leased about one thousand acres of sea bottom, on which are a million oysters of this species, which yield from 30,000 to 50,000 culture pearls annually. ”

“ A larger form, attaining a foot in diameter and a weight 10 ℔ per pair of shells, is considered as a distinct species by Dr Jameson and named Margaritifera maxima. It is found along the north coast of Australia and New Guinea and the Malay Archipelago. The nacreous surface of this shell is white, without the black or dark margin of the common species; it is known in the trade as the silver-lip, gold-lip and by other names. It is the most valuable species of mother-of-pearl oyster. ”

“ According to modern scientific investigation, the formation of the pearl does not seem to be the result of healthy natural causes, but comes from the efforts of the oyster to rid itself of some foreign substance, like a grain of sand, a bit of shell or vegetation, or some unwelcome visitor in the shape of a small water insect. ”

“ Allied to the true oysters are the Pearl Oysters, especially abundant around Ceylon. These have the interior of the shell lined with mother-of-pearl, and when foreign particles get between body and shell they are covered with the same substance, thus forming the pearls used for adornment. These oysters are obtained by diving; the animal matter is allowed to rot, leaving the pearls behind. The shell is also of value, furnishing material for knife handles, buttons, etc., though most of our pearl buttons are now made from the shells of fresh-water mussels from the Mississippi valley. ”

“ Hindu workmen preparing to drill pearls, Marichchikadde, Ceylon
115Since 1904, a steamer has been employed each season by the government for dredging oysters in connection with experiments in oyster-culture. The officer in charge of this work concludes that “dredging is economically a more sound method of fishing than is diving.” [141] This view is disputed by the superintendent of the fishery, who points out that the average catch by the steamer when dredging mature oysters only slightly exceeds that of an ordinary diving boat, and the cost of maintenance and operation is vastly greater. ”