The shell of the nautilus grows through extending the shell and increasing the number of chambers.


"The chambers [of the nautilus] are connected by the siphuncle, a strand of living tissue enclosed in a chitin tube that spirals from the posterior mantle through all preceding chambers of the shell, including the earliest one. As the animal grows, the shell aperture is extended and the body moves outward while the siphuncle is elongated before a new septum and thereby a new chamber is built. Each new chamber is filled at first with a watery fluid, called cameral liquid, which is gradually removed by the epithelium of the siphuncle." (Westermann 2004:930)

Journal article
Shell growth and chamber formation of aquarium-reared Nautilus pompilius (Mollusca, Cephalopoda) by X-ray analysisJournal of Experimental Zoology Part A: Comparative Experimental BiologyNovember 23, 2004
Bettina Westermann, Ingrid Beck-Schildwächter, Knut Beuerlein, Erhard F. Kaleta, Rudolf Schipp

Living System/s

Chambered NautilusNautilus pompiliusSpecies