Sorry @amy-sousley this looks like a rock.

@stacy-young Sorry, I think this is a rock.

@mike-reed I think you have part of a sea robin skull (fish). Family Triglidae.

Hi @bernard-weich can you provide us with a little more context please? (Near what city, state/province is it from?)

@joseph-johnson Yes, this is Lepidodendron.

@rhonda-ellis Sorry, this is a rock. If you see shell or a repeating pattern, then it’s probably a fossil.

@gail-chapman@corinne-daycross Chances are this came from a Pennsylvanian formation in the Douglas Group. This appears to be Alethopteris though Pecopteris can’t be ruled out entirely. I doubt there is any venation preserved but that would differentiate the two. It is not Sphenopteris because the pinnules are not lobed and it is not Neuropteris…[Read more]

@rhonda-ellis Sorry, it’s a rock.

@charles-du Yes. To my knowledge, both Lepidodendron and Sigillaria have Stigmaria type roots. Both are scale trees and lycopods with Lepidodendron having rhomboid leaf scars and Sigillaria having hexagonal leaf scars.

@charles-du It’s a stem of some sort. Sadly, I can’t tell of what.

@marion-marshall Very nice specimen!

@jami-kerr I believe there is a branching bryozoan stem in the upper right and a crustose bryozoan in the center.

@charles-du Yes! Stigmaria. Another one of those morphogenera where each organ gets ots own name. This name applies to the roots of scale trees (Lepidodendron).

@charles-du These are great by the way. Enjoying this!

@charles-du So the name given to this would be Artisia. It is the pith cast (inner part of the stem) of an early (but fully) seed plant called Cordaites. Plant fossil nomenclature is weird because we don’t always know what stem goes with what leaf or reproductive part and so although from the same plant, each organ gets its own genus (generic) name.

@charles-du Ah, sorry just saw the comment. Yes, that is correct!

@charles-du Calamites

@charles-du Yes! 😁

@charles-du What are the dimensions? I’m leaning towards some sort of stem but a Cordaites leaf is possible. This is too early for palm (palms evolved during the Cretaceous).