Platystoma gastropod from Iowa

My friend Nathan gave me a bag full of fossils from the Lime Creek formation (Devonian, Fransian stage) that he collected at the Fossil and Prairie Park Preserve near Rockford, Iowa. Included in the sample were these two steinkerns (internal shell molds) of a Platystoma like gastropods.

Specimen #1

Specimen #2

Thanks Nathan for the fossils!