Belemnites

Hi, The top one is probably Passaloteuthis bisulcata, from the Grey Shale Member. The rocks at Runswick are too high up for P.turris.  Not sure about bottom left, Par. zieteni is certainly a possibility depending on where it came from.

17 hours ago, TqB said:

The top one is probably Passaloteuthis bisulcata

Thanks for the lead, I will read up on this! It was found between Runswick and Kettleness, past the tenuicostatum area, if that makes a difference on the possible strata.

I don't remember exactly where the smaller one was from, but all of our collecting happened between Port Mulgrave and Kettleness or Saltwick Bay.

3 hours ago, debivort said:

Thanks for the lead, I will read up on this! It was found between Runswick and Kettleness, past the tenuicostatum area, if that makes a difference on the possible strata.

I don't remember exactly where the smaller one was from, but all of our collecting happened between Port Mulgrave and Kettleness or Saltwick Bay.

That means there's a chance that the larger one is an Acrocoelites, especially A. trisulculosus from the Mulgrave Shale Member (Jet Rock) above the Grey Shales. It would ideally show three apical furrows while Passaloteuthis has only two. The third (ventral) one can be faint though. The Jet Rock is a lot harder and darker too.