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Synopsis of the contents of the British museum
Synopsis of the contents of the British museum Author:British Museum Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: are pale brown and transparent; those of the Oyster, are white and opaque; and those of the Muscles are either white or purple; while those of the shells which h... more »ave a pearly lustre, as the Aviculce, Uniones, and Anodons, partake of the same mild brilliancy. As the peculiar lustre of Pearls greatly depends on their more or less globular form, the Chinese have attempted, for no very honest purpose, to make the pearly inside coat of some of the pond-muscles assume that shape, by placing hemispherical pieces of mother of pearl, between the animal and the shell, which it eventually covers with a pearly coat (see Case 83). In other countries, spurious Pearls have been produced, for an equally laudable object, by placing pointed pieces of wire in a similar situation. Case 88 contains the shells of Branchiopodous Mollusca, which are inclosed by two regular shelly valves. They have no distinct head, but the mouth is placed on the hinder part of the cavity, and is furnished with two long spirally twisted arms, by which they reach their food; the organs of respiration are placed on the edge of the mantle. All these shells are attached to marine bodies: some of them are regular, and somewhat like a Grecian lamp in form, and have therefore been called Lamp-shells. They are attached by means of a tendinous band, which passes out of the hole in the apex of the upper valve, as in the Terebratulce and Spiriferi: others, as in the Lingula, are attached by a tendinous tube, resembling the stem of the Barnacles, which projects between the apex of the gaping valves. The Discince, on the other hand, have the tendon passing out of a linear slit near the middle of the under valve; and the Cranice are immediately attached by the outer surface of their shells. J. G. Children. LONG GALLERY. T...« less