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.
The Rough Pinna, ([Pinna rudis].)
The Pinna is a marine shell; most of the species are large, and the shells very thin in proportion to their size. That represented in the engraving is found in the American seas, and is sometimes as much as a foot and a half in length; it is by no means rare. There is a species found in the Mediterranean, in about five or six fathoms water, which is much sought after by the inhabitants of Sicily and Calabria, not only as an article of food, but also for the sake of its beard, or byssus, of which, in many places, a kind of cloth is made, very remarkable for its softness and warmth. The fishermen, to obtain the [Pinna], make use of a kind of iron rake, called a crampe, with teeth a foot in length; when the shells are drawn up, the beards are found to be torn in some part of their substance. If a sufficient length remains attached to the animal, to render the fibres available for the purpose of spinning, they are cut off close to the shell: they are then dried and spun, and afterwards woven into gloves, stockings, caps, and even garments of much larger size.
Pinna rudis.
The threads of which the byssus is formed are extremely fine, and of equal thickness throughout their whole length, very strong, and of a dark morone colour, which is exceedingly permanent.
This curious kind of cloth was long since known to the ancients; but at present its manufacture is very limited, from the great scarcity of the [Pinna], and the number of beards necessary to make even so small an article as a pair of gloves. But it is supposed, that if the shells were placed in more favourable circumstances, in preserves, &c., they would increase much more rapidly.
These shells are found in the seas of all hot climates, but the British shores possess but one species, the Pinna lævis of Donovan; this is of a horny colour, clouded with brown, and attains a considerable size.