With the appearance of yellow in the trees, reminders from the dean to submit the syllabi for the Fall semester, it all points to the end of summer. It also means getting in as much rock-breaking time before school duties resume. A trip to Arkona - my nth one this year - did not yield up many wow specimens. My goal of finding a full Greenops widderensis has not borne much fruit this year for some odd reason. But I did come close on a few occasions. This time, I crossed the river to the south bank for the first time (not to be confused with the south pit). While on the south side of the river, there were some mighty large corals. I left them there since I already have enough coral, and I didn't fancy hauling all that around with me for the rest of the day! This one is a real heartbreaker. Two nearly complete Greenops (one of which is just an impression), with a third one showing. As readers of my blog already know, the trilobites in the Widder Formation are quite delicate and flaky. Not only does the Widder shale not commonly follow regular bedding planes, breaking anyway they like, but any exposure to rain will cause them to fracture and crumble into little chips. Finding these bad boys intact, and not just endless moults, is rare. After about two hours on the south bank, there really wasn't much to find. The cliffs were too vertical to risk chopping out benches, and all the fallen slabs had been split and picked over. And so I defaulted to my usual location on the north side of the river, attempting to continue some benches and find some trilobites. While splitting for a few hours, this oddball showed itself. No, not a fossil snowflake, but a hederellid - a kind of branching colonial animal that usually affixes itself to brachiopods and corals (thanks to Don C. on The Fossil Forum for the ID). Some of the orthocone nautiloids that come out of the Widder can be very impressive as they are usually pyritized. However, they are also very delicate in that unforgiving shale. The pieces below all belong together, but it will be a matter of Humpty Dumpty to put them into their proper shape as some of the pieces crumbled into nothingness when I attempted to clean them. Derp. The grey shale pieces here all come from a very thin layer I was working where it seemed the Greenops were coming out relatively whole. Following it horizontally, and spot-checking vertically at various parts of the strata, ended up in the trail going cold - just butts, bits, and pieces. Notice the squished one at the top middle... ...So I gave it a quick and careful application of the engraver to pop off some of the matrix. I might risk doing a bit more to see if the cephalon is still there. One has to be very careful in using vibration tools as the trilobite itself is liable to flake off. I might apply some quick crazy glue before trying again. It was getting close to departure time, so I made my way out of the river and woods back to the north pit, and then scanned the Hungry Hollow Member for little bits. This fairly decently sized Platyceras was only showing a tiny bit of spine from the dirt. Digging it out, here it is in its large glory. Spines on this coprophagous species usually only appear on the juveniles, which can be very tiny (0.5 cm or less!), so it was surprising to see them on such a large one. Here are two other pictures of the same specimen from different angles: That's about it for this time. Next weekend I hope to be making a trip back in time to the Ordovician - stay tuned!
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Kane Faucher
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February 2024
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