Bordering on Perfect

What do Roman senators and snails have in common?

A natural purple dye used to color the border of Roman senators togas was derived from the secretions of the Murex sea snail. The ink is sprayed into the water to cover the retreat of the snail, when it is attacked. The Phoenicians of Tyre farmed the snails and dealt in the precious purple dye, often called Tyrian purple.