"So called from their resemblance to a ram's horn."-Whitney, 1902

Ammonite

"So called from their resemblance to a ram's horn."-Whitney, 1902

"A genus of cephalapodous mollusca, pretty generally known by the name of Paper Nautilus, and in consequence of similarity in the form of the shell, often confounded with the genus Nautilus, but in fact much more nearly allied to the Poulpe (Octopus)." — Chambers' Encyclopedia, 1875

Argonaut

"A genus of cephalapodous mollusca, pretty generally known by the name of Paper Nautilus, and in consequence…

"Argonaut with the shell." — Goodrich, 1859

Argonaut (with shell)

"Argonaut with the shell." — Goodrich, 1859

"The argonaut retired within its shell." — Goodrich, 1859

Argonaut (within shell)

"The argonaut retired within its shell." — Goodrich, 1859

"Argonaut without the shell." — Goodrich, 1859

Argonaut (without shell)

"Argonaut without the shell." — Goodrich, 1859

The greater argonaut (Argonauta argo) is a cephalopod and a species of pelagic octopus also known as a paper nautilus.

Greater Argonaut

The greater argonaut (Argonauta argo) is a cephalopod and a species of pelagic octopus also known as…

The nautilus is a true mollusc. (a) mantle; (o) eye; (t) tentacles; (f) funnel.

Nautilus

The nautilus is a true mollusc. (a) mantle; (o) eye; (t) tentacles; (f) funnel.

"Section of a nautilus showing its interior." — Goodrich, 1859

Nautilus

"Section of a nautilus showing its interior." — Goodrich, 1859

The name applied formerly to a large genus of mollusks. At present it is confined to only three existing species. Fossil remains indicate that more than one hundred species lived in the different geological periods.

Nautilus

The name applied formerly to a large genus of mollusks. At present it is confined to only three existing…

A marine creature of the class Cephalopoda. They are found only in the western Pacific, inhabiting waters around coral reefs.

Nautilus

A marine creature of the class Cephalopoda. They are found only in the western Pacific, inhabiting waters…

An illustration of a female nautilus without the shell. "m, The dorsal "hood" formed by the enlargement of the outer or annular lobe of the forefoot, and corresponding to the sheaths of two tentacles; n. Tentacular sheaths of lateral portion of the annular lobe; u, The left eye; b, The nuchal plate, continuous at its right and left posterior angles with the root of the mid-foot, and corresponding to the nuchal cartilage of Sepia; c, Visceral hump; d, The free margin of the mantle-skirt,...; g.a, Points to the lateral continuation of the nuchal plate b to join the root of the mid foot of siphon." (Britannica, 1910).

Female Nautilus without Shell

An illustration of a female nautilus without the shell. "m, The dorsal "hood" formed by the enlargement…

An illustration of a female nautilus without the shell. "c, points to the concave margin of the mantle-skirt leading into the sub-pallial chamber; g, the mid-foot or siphon; k, the superficial origin of its retractor muscles closely applied to the shell and serving to hold the animal in tis place; l, the sipjuncular pedicle of the visceral hump broken off short; v,v, the superior and inferior ophthalmic tentacles." (Britannica, 1910)

Female Nautilus without Shell

An illustration of a female nautilus without the shell. "c, points to the concave margin of the mantle-skirt…

An illustration of the postero-ventral view female nautilus without the shell. "a, Muscular band passing from the mid-foot to the integument; b, The valve on the surface of the funnel, partially concealed by the inrolled lateral margin of the latter; c, The mantle-skirt retroverted; an, The median anus; x, Post-anal papilla of unknown significance; g.n., Nidamental gland ; r.ov, Aperture oft he right oviduct; l.ov, Aperture of the rudimentary left oviduct; neph.a, Aperture of the left anterior renal sac; neph.p, Aperture of the left posterior renal sac; viscper, Left aperture of the viscero-pericardial sac; olf, The left osphradium placed near the base of the anterior gill-plume." (Britnnica, 1910)

Female Nautilus without Shell

An illustration of the postero-ventral view female nautilus without the shell. "a, Muscular band passing…

An illustration of a female (bottom) and male (top) nautilus.

Female and Male Nautilus

An illustration of a female (bottom) and male (top) nautilus.

The paper nautilus is closely related to the octopus. It creates its own thin shell, or egg case, in which it hides when disturbed.

Paper Nautilus

The paper nautilus is closely related to the octopus. It creates its own thin shell, or egg case, in…

The paper nautilus is closely related to the octopus. It creates its own thin shell, or egg case, in which it hides when disturbed.

Paper Nautilus

The paper nautilus is closely related to the octopus. It creates its own thin shell, or egg case, in…

"Argonauta argo, the "Paper Nautilus," female. The animal is represented in its shell, but the webbed dorsal arms are separated from the shell, which they ordinarily embrace." — Encyclopedia Britannica, 1893

Paper Nautilus

"Argonauta argo, the "Paper Nautilus," female. The animal is represented in its shell, but the webbed…

"Pearly Nautilus. e, eye; h, hood, a muscular portion of the foot which protects the softer parts; s, siphon; se, septa, separating the successive chambers of the shell; sp, siphuncle; t, tentacles." — Galloway

Pearly Nautilus

"Pearly Nautilus. e, eye; h, hood, a muscular portion of the foot which protects the softer parts; s,…

"Pearly nautilus with half the shell removed." —Davison, 1906

Pearly Nautilus

"Pearly nautilus with half the shell removed." —Davison, 1906

The Pearly Nautilus (Nautilus Pompilius) is the only living representative of a unique form of cephalopod, recorded in fossils for over 500 million years. The shell, pearly and beautifully colored, is spirally formed and consists of a series of chambers separated by curved cross plates thus exemplifies the "chambered shell". The nautilus is a bottom feeder on Crustaceans, usually in deep water.

Pearly Nautilus

The Pearly Nautilus (Nautilus Pompilius) is the only living representative of a unique form of cephalopod,…

The Nautilus Shell is a marine creature, it is shown in its natural form. It was usually placed on feet and elegantly mounted in metal, and used as a drinking vessel.

Nautilus Shell

The Nautilus Shell is a marine creature, it is shown in its natural form. It was usually placed on feet…