Nautilus

(naw'te-lus.) [From Gr. nautilos, a sailor.] (Zool.) A genus of mollusks, O. Tetra branch i at a, consisting in a single living representative species, N. poтpili us, which has a shell formed of one continuous piece, rolled into a spiral form, and having its cavity divided into a great number of chambers by transverse partitions, each of which has a perforation, the various perforations being connected with each other by means of a pipe carried the whole length of the shell. The fo il species of nautilus, which are very numerous, are found in all geological formations. The name Paper Nautilus is sometimes given to Argonaut a Argos. See ARGONAUT IDE. [s. 633]