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So I'm back again with more plant fossil questions, but this time I am hopefully a little less clueless. I got Jack Wittry's guide to Mazon Creek Flora and have been trying to learn as much as possible. I am interested in comparing what I have found so far to an earlier study by Roger Boneham (http://journals.iupui.edu/index.php/ias/article/download/8143/8102) on the Pennsylvanian fossil flora and fauna of the Chieftain Mine site (now Fowler Park, Vigo County, IN) but I am running in to some nomenclature issues that make it difficult to decipher which fossils were found in the study. I am also having trouble differentiating some fern species with very similar venation (at least to my untrained eye). Jack was kind enough to clear up some of my questions about general identification and taxonomy in a previous post and he stated that based on what venation he could see and the form of the pinnules, the fern in question appeared to be Acitheca (Polymorphopteris) polymorpha. I have spent a good few hours since then going over numerous ferns with a magnifying glass and a bright light and have been able to see the veins on many of the specimens relatively clearly. Since I think my photographs obscure the venation even further, I have posted photos and sketches based on what I can see below: - 4.5 X 2.25cm (the nodule) Sketch - - 6 X 4.5cm (nodule) - 5.5 X 3.25cm - Sketch showing more clearly the transition in shape of the pinnules closer to the base - 8 X 4cm I have also found a negative of what appears to be the same type of fern that is ~11cm long and similar in form to the first picture. So I guess my question is, are all of these Polymorphopteris, are they something different, or are they a mix of species? So far, all of the ferns I have found with visible venation (~20) appear to be the same thing to me (similar venation, size, and form) so I suspect this has to be one of, if not, the most common species at this site. Boneham notes Asterotheca miltoni as "one of the most common species" and I suspect this is what I am finding. The only problem, is that it seems this species has been sunk (or at least reassigned) and in his book, Jack notes that both Polymorphopteris and Lobatopteris have been previously called Asterotheca/Pecopteris miltoni. For those interested, so far Cyperites preservations are the second most abundant fossil I've found with Macroneuropteris and Annularia stellata following next in line respectively. I apologize if I have asked too many questions at once or if my ignorance is showing in any all too obvious ways haha...I am still learning and it is a steep learning curve! I really appreciate all of the help you all have given me so far and I look forward to hearing your comments. -Andrew