The Nassas of France are very destructive to the oyster beds of that nation, an adult “borer” being able to perforate the shell of a large oyster in a single night. So numerous are these pests that a single acre has yielded over a thousand individuals. As a result of these depredations the French oystermen carry on a relentless war against the Nassa, destroying thousands of animals annually. With all this persecution the mollusk still exists and even increases in numbers. The dead shells of this genus are a favorite home for the hermit crabs of small size, and it is to be suspected sometimes that other than dead shells are appropriated. We fear that a sort of piracy is resorted to by the hermit crab, resulting in a kind of “walk-the-plank” end for the mollusk, before the new tenant takes possession of the “home.” Of the many varieties of tropical shells, few exceed the Volutes, or bat shells, in beauty or variety of coloration. They are found in most parts of the world, although strangely enough none are now living in the seas of Europe, but they are most abundant and more highly colored in the tropics and subtropics. The animal is carnivorous, and the long, fang-shaped teeth are certainly suggestive of predaceous habits. The shells are variously colored, some being mottled, some with zigzag or lightning-like markings, while others have spirally arranged dots and lines. One species (Voluta musica, figured on the plate), has received its name from a more or less fanciful resemblance of the surface of the shell to a musical staff, the spiral lines being grouped in sets of four or five and the dots being arranged as notes. In some specimens this resemblance is quite close. The smooth and polished shell of some volutes is due to the fact that the greater portion is covered by a reflected part of the large foot. On the sandy shores of subtropical beaches certain graceful and polished animals bury themselves from sight in the sand. These are the olive shells (Oliva) whose bright colors and highly polished surfaces rival even the gaudy Volute in beauty. The foot may be described as plough-shaped and is admirably adapted for digging rapidly in the sand, so that the shell may be hidden from sight on the approach of enemies. The long siphon is thrust up through the canal in the anterior part of the shell and its end protrudes above the sand. The high polish of the surface is due to the shell being enveloped in the voluminous foot; hence it has no epidermis. The aperture is so narrow that it is difficult to understand how the animal gets in and out. The olives are very numerous in individuals; when one is found hundreds are sure to reward a patient search.