The singular figure of this shell renders it very remarkable;
externally its appearance is very rude and irregular, but, on the other
hand, the inner surface is equally beautiful, being covered with the
most brilliant mother-of-pearl. The different species of the Malleus
are all marine, and found in the seas of hot climates, and the rarity
of some causes them to be very valuable, and much sought after. Like
the neighbouring genera, the animal is furnished with a byssus, or
beard, by which it adheres to the rocks.