Page:Natural History, Mollusca.djvu/79

 the shell of the slug, which is also enclosed within the mantle; and both are formed in the same manner, namely, by a deposition of horny or shelly matter in a fluid state from the sides of the containing cavity.

The animals of this Family have ten arms, two of which, greatly longer than the rest, are very slender except near their tips, which are dilated; these extremities alone are furnished with suckers. The other eight arms are short, thick, and furnished throughout their whole length with suckers, forming a double row along their under surface.

The body is generally lengthened, more or less flattened, with the skin dilated on each side so as to form a pair of wings or fins. It is probably by means of the impetus afforded to the body by these expansions, that some species of the Family are enabled to throw themselves out of the water, and to shoot along through the air to a considerable distance with a motion that resembles flight. These are commonly called Flying Squid.

Mr. F. D. Bennett describes a portion of the Northern Pacific as peculiarly animated by the presence of various oceanic creatures. The Albacore, the Sword-fish, the Barracuda, the Bonita, the Flying-fish, are mentioned, and among them the Squid, whose movements closely resembled those of the last-named volatile fish. "During a calm, in lat. 30° N., the Flying-squid appeared in larger flights than we had ever before witnessed; persecuted probably by the Albacore (which select this tranquil time to descend deep in the water, and to rove far from the ship in quest of food) they rose from the sea in large flocks, leaping over its smooth surface, much in the same manner, and to the same