Nautipus or Octolus?

 

This is a replica of some type of prehistoric nautilus on display at the Houston Museum of Natural Science.  It looks a lot  like a modern nautilus, except the modern ones that I've seen have more tentacles and those tentacles are "stringy".  This one has eight tentacles (the 8th one is under the shell) and they're  octopus-like with suction cups.  I often get so focused on photographing something at the museum that I forget to look at the species name, and unfortunately my Google skills also failed to yield the proper name.

So I'll just call him "Nautipus".  Or "Octolus".  Which one do you like better?

From a photographic standpoint, I chose to process the photo for a low-key lighting look.  The image off the camera had a very normal exposure.  But I thought the low-key effect suggested more strongly what Nautipus/Octolus must have looked like in his natural environment, as opposed to the clinical look of the well-lit display case.