Shell-ing a-Round #13 - Nautilus

Next shell in my series is Nautilus - lots of stories about it, and its chambers and all the math with Fibonacci series, as you probably know. I do like it very much, because of the beautiful stripes it has on the shell and its rather strange "look" when alive. I started with just the shells in the sea water, on the beach, again ACEOs. First one today, and the second tomorrow.