Cephalopods? & Crinoid Pieces

[collector]

This is about a 6" x 6" rock with crinoid pieces that are mostly on one side and what are maybe some straight shelled cephalopods. There is this circular piece that I don't know what it is. It is somewhat translucent when wet. There are other circular pieces as well as misc. bits and pieces.

Can anyone confirm whether these are cephalopods and if the circular pieces are related?

Thank you for looking.

Patti

[Pumpkinhead]

Your Crinoid pices diagnosis is correct, and the picture in the top left appears to be a cephalopod. I don't know the specific species names, but I'm sure someone will. Nice finds!

[Herb]

Your guesses look correct to me.

[Pumpkinhead]

A rather interestingly shaped shell on the ceph though

[4circle]

They're orthocone nautiloids. The central item in the first photo is looking directly down the axis at a single septum with the siphuncle central (i.e. the nautiloid continues into the rock in line-of-sight), and the bottom-left is the same except the siphuncle is slightly off-centre (platyconic condition). Your third photo is a cross-section though a less well preserved orthocone nautiloid, showing all the chambers.

Nice piece

[Bev]

Beautiful piece for your collection! One rock and you have several positions including one showing the siphuncle!

[collector]

Thank you to all for your help. Your description 4circle was very helpful. There is a fairly narrow band in the rock where they all are. It is very busy there and not much outside of it except for the crinoid pieces on the one end. Do you think it is possible to tell what kind they are? I was wondering if gomphocerus lived too early in time to be found in a Middle Devonian period. I'm adding a couple more pictures of two stubbier specimens.

Patti