Silurian Orthoconic Nautiloid

[Peat Burns]

Hello,

 

This appears to be an internal mold/cast of an orthoconic nautiloid, and therefore I am not sure if there is sufficient detail to get an ID. This is from the Niagaran Series, Burnt Bluff Group, Hendricks Dolimite (Fiborn Member) Formation (middle Silurian) of Schoolcraft County, Michigan (Upper Peninsula).  Looking for more info on possible identity from those familiar with the Silurian orthocones from this area. @FossilDAWG?

Cross section

 

[piranha]

It matches well with this Burnt Bluff cephalopod: Stokesoceras romingeri

 

 

figure from:

 

Foerste, A.F. (1924) 

Silurian cephalopods of northern Michigan.

Contributions from the Museum of Geology, University of Michigan, 2(3):19-120   PDF LINK

[Peat Burns]

20 minutes ago, piranha said:

It matches well with this Burnt Bluff cephalopod: Stokesoceras romingeri

 

 

figure from:

 

Foerste, A.F. (1924) 

Silurian cephalopods of northern Michigan.

Contributions from the Museum of Geology, University of Michigan, 2(3):19-120   PDF LINK

Hey!  That looks like a likely match and a valuable paper!  Thanks @piranha!

[FossilDAWG]

These fossils are actually the siphuncle by the way.  I don't think the whole shell (with camerae, exterior, or living chamber) has ever been described (or found).

 

Don

[Peat Burns]

1 hour ago, FossilDAWG said:

These fossils are actually the siphuncle by the way.  I don't think the whole shell (with camerae, exterior, or living chamber) has ever been described (or found).

 

Don

Thank you.

[Monica]

That is one cool-looking fossil - I am 

[Peat Burns]

7 hours ago, Monica said:

That is one cool-looking fossil - I am 

It is pretty cool. Definitely glad to add it to the collection.