The Univalves—A Higher Scale of Animal—The Gasteropoda—Limpets—Used for Basins in the Straits of Magellan—Spiral and Turret Shells—The Cowries—The Mitre Shells—The Purpuras—Tyrian Purple—The Whelk—The Marine Trumpet—The Winged-feet Molluscs—The Cephalopodous Molluscs—The Nautilus—Relic of a Noble Family—The Pearly Nautilus and its Uses—The Cuttle-fish—Michelet’s Comments—Hugo’s Actual Experiences—Gilliatt and his Combat—A Grand Description—The Devil-Fish—The Cuttle-Fish of Science—A Brute with Three Hearts—Actual Examples contrasted with the Kraken—A Monster nearly Captured—Indian Ink and Sepia—The Argonauta—The Paper Nautilus.
And now, the bivalves having had their turn, let us direct our attention to a higher class of animals, to which nature has been more generous. They, unlike the first-named molluscs, have heads. “This head,” says Figuier, “is still carried humbly; it is not yet os sublime dedit; it is drawn along an inch or so from the ground, and in no respect resembles the proud and magnificent organ which crowns and adorns the body of the greater and more powerfully organised animals.” The Acephalous, or “headless,” must now make way for the Cephalous, or headed mollusca. These again are divided by the scientists into three great classes, the Gasteropoda, Pteropoda, and Cephalopoda.
The title of the Gasteropoda is derived from two Greek words signifying belly and foot; the raison d’être of that title being that these animals progress by means of flattened discs placed under their bellies. The snail, slug, and cowrie, are leading types of this class.
In the Pteropoda (from Greek words signifying wing and foot) locomotion is effected by membranous fins or wings.
Lastly, the Cephalopoda are so called because they have prominently, as a class, [pg 140]heads and feet, locomotion being effected by a set of tentacles (arms or legs, as you will). The cuttle-fish and devil-fish (or octopus) are types of this important series of animals.
THE LIMPET (Patella).
The vastness of the subject precludes the possibility of details, and for evident reasons a few of those inhabiting the sea itself can only be considered here. Among the “Gasteropods,” as they are familiarly termed, the limpets constitute a numerous family. The scientific name Patella (a deep dish or knee-cap) was given to them by Linnæus, the form of their shells fully warranting the title. Some of them are oval, others circular; but all terminate in an elliptic cone. Otherwise they are varied enough, some being smooth, but others having ridges or scales on the outer surface, the edges being often dentated. Their colours are very varied. The head of the animal itself has two horns and two eyes; its foot is a thick fleshy disc, and when it means to hold on to a rock we all know how difficult it is to dislodge it, for the said foot becomes a kind of sucker. Some of those from the coast of Africa and the Antilles, &c., have elegant forms, as witness Patella umbella, P. granatina, P. longicosta, and others. Although often eaten, they are very tough and indigestible. In Southern seas they attain to a great size; for example, in the Straits of Magellan the natives use for culinary purposes species as large as a slop-basin.
TURBO.