The nautilus breathes by means of two pairs of gills; it feeds on crabs and other animals, which it catches with its long, slender tentacles (numbering more than 90) that encircle the mouth. There is a thickened area over the head, called the hood, that acts as a protective lid when the animal withdraws into the shell. The nautilus lives in deep water in the S Pacific and Indian oceans. It is active at night; during the day it stays hidden in coral crevices. It is hunted for its shell, which is used in jewelry and ornaments.
The paper nautilus , which is not a true nautilus, is a close relative of the octopus, belonging to the order Octopoda. The true nautilus is classified in the phylum Mollusca , class Cephalopoda, order Nautilida, family Nautilidae.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.
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