murex a Latin name which is used in default of anything more convenient to denote the gastropods of the family Muricidae. These are best known as the source of purple dyes in antiquity. Purple was the imperial colour, used for Caesar’s robe and for the sails of Cleopatra’s warship; and its production was an important industry, carried out at Tyre and Sidon and other places in the Mediterranean.

However, the creatures inside murex shells are edible and are consumed in some parts of the world. The best Mediterranean species is Bolinus brandaris, whose shell may measure 9 cm (3.5"), but there are others. Phyllonotus trunculus (French rocher pourpre) and Ocenebra erinacea (French perceur) are, or used to be, popular foods in the Adriatic region (the genus name of these three was formerly Murex). Vernacular names for these shells echo those of antiquity. The Provençal burez is evidently derived from murex; and the name porpora, used on the Italian Adriatic coast, comes from the classical (and modern) Greek porphyra.