Читать книгу The Book of Shells. Containing the Classes Mollusca, Conchifera, Cirrhipeda, Annulata, and Crustacea онлайн

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The common Columbella is found in the Atlantic Ocean near the island of Gorée, and in the West India Islands; it is about three quarters of an inch in length. It is a sea-shell, and is found upon the coast; it possesses a very small oval operculum attached to its foot.

Family PURPURIFERA.

The notch at the base of the shells of this family is a kind of groove bent backwards and upwards, but not properly forming a canal, all the genera have an operculum. The name Purpurifera has been given to these Trachelipodes, because some of the genera contain in a peculiar reservoir the colouring-matter with which the Romans, and other ancient nations, dyed their beautiful and well-known purple, which was so much in use before the discovery of cochineal.

The Harp shells are found in the Indian seas, and in great abundance also in the Red Sea. A very curious fact appears in the history of the animal of the Harp which deserves notice. It was observed a long time back by a German naturalist named Bon, but had since then been either forgotten or disbelieved: a recent traveller has confirmed its truth, although he notices it as a new discovery; it is as follows:—