.....I think it's an archaeological dig - a midden site - and you're looking at ~ 200 years of prehistoric mans littering/feeding. The arrows point to broken urns. Either that or it's a festering leg with tons of naggots
Long answer (my weak guesses ): Stomach contents...and it looks like there's a bunch of calcareous "stuff" in there (or at least it looks white and glisteny and jagged like calcareous fragments). I was under the (incorrect?) impression all ceph hard parts were chitinous except for cuttlebones and nautilus shells, so I'll say not ceph parts. But if it's not...then I'm not sure what it IS. I could swear that the items with the arrows look really familar, but...I just can't think what. And maybe these aren't actually hard parts at all.
Can I actually see a third "thing" that's similar to the other "arrowed things," directly above the top "thing?" If it is, well, those remind me most of some squid suckers...I think I've seen some with somewhat serrated edges near the inner rims as seen here.
But...I sure wouldn't bet money on any of that...so, mainly, I just haven't a clue! :?
Indeed, Rusty, there is a third Thing of the same origin - well spotted - and probably more. As to the chitinous nature of squid parts... this is true of *most* squid (hint, hint) (also currently unpublished information).
Good guesses so far, on the right track except for one (ahem, STEVE). Any other takers?
If those ARE shell fragments... Some few months ago before I went on my posting hiatus, Steve told me that Archis spend their time as adults in the deep water column, feeding on fish. If those ARE shell fragments, then that means: (A) They cruise around the bottom of the sea looking for food AND/OR (B).... There's a shelled, free-swimming creature in the deep water column...
.....ok, they're not shell fragments .... but I'll not be the one to give any more clues or secrets away.....
..... that image TTF put online is the first of its kind in the world - I can assure you that nothing like it has ever been seen before. In fact it is just so amazing that we even butted heads (as geeks do) when the first cut was made and unknown white objects (and additional scrambled mass) were revealed.