The paper nautilus is excessively thin, white and imperfectly calcified and totally unconnected to the octopus inhabiting it. The female nautilus, also known as an argonaut is an octopus that constructs its own ornate shell or egg case from a substance it secretes from two of its 8 tentacles.White shell with dark ridges on the curl.argonauta argo, paper nautilus, octopuses