Argonaut, << AHR guh nawt, >> is an eight-armed animal that lives near the surface of warm seas worldwide. It feeds on such animals as small fish. The argonaut swims slowly by forcing a jet of water through its siphon, a tube-shaped organ under its head. Female argonauts may reach more than 18 inches (45 centimeters) long. Males rarely grow more than 1 inch (2.5 centimeters) long. The female argonaut builds a fragile, paper-thin shell. Two of the female’s arms have broad flaps of skin that release liquid shell material. The shell quickly hardens and is covered by the flaps. Female argonauts live in the shell and store their eggs there. The name paper nautilus, often used for the argonaut, comes from this shell. Male argonauts make no shell.
People once believed that the argonaut sailed on water by using two enlarged arms as sails. It was named after the sailors on the Argo, a ship described in the Greek myth of the Golden Fleece.
