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I know some of you find very complete nautiloids that are much larger but here in Texas they are often smaller and fragmentary, though the pieces can be well preserved and easy to extract from the loose shale of the Graham Formation at Jacksboro Texas. I had many fragments separated into boxes labeled "Pseudorthoceras" and "Mooreoceras" for smaller and larger segments respectively. Then I saw a paper that invalidated the latter genus, Revision of Some Common Carboniferous Genera of North American Orthocerid Nautiloids, Kröger & Mapes 2005, which made all of my specimens Pseudorthoceras knoxenses. This got me wondering what these creatures might have looked like whole so I started to gather a few fragments that might fit together in a continuous shell, including a piece with the protoconch and one with part of the body chamber. The result had one empty space which I filled with a clay reconstruction, then made a plaster mold from which I poured a plaster cast to fill the gap. I used super glue to hold everything together so I could take it apart with acetone if I wanted too. It may make a good display fossil for our table at local events though so I'll probably donate it to the Dallas Paleontological Society. The second section from the large end is the fake part. The rest are all genuine fossils from the same site but collected over several years, so not even considered to be associated. I'm pretty sure they are all the same species though. The whole thing is 38cm long and came out fairly straight considering what I had to work with..

Pseudorthoceras is a bit of a mystery locally for me still. They are probably the most common straight shelled cephalopod I find. I also found at least one Mooreoceras. From what I understand, Mooreoceras and Pseudorthoceras are both classified under the Pseudorthoceratidae Family