Читать книгу The Book of Shells - Society for Promoting Christian Knowledge . Committee of General Literature and Education - Страница 16

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.