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I recently have been reanalyzing some fossils I found with @Tales From the Shale and another friend on October 8th, 2022 at a Pennsylvanian era roadcut in Oglesby Illinois! One of the specimens I had previously put under a dissecting scope, but was still unsure about its exact ID. I recently took a look at the specimen again a couple days ago and I believe its a partial tooth of a large ctenacanthiform shark. Here is the specimen under a dissecting scope! After a closer look, I noticed the parts of the tooth that could have connected to the medial cusp and lateral cusp on the left side of the tooth. For comparison, I compared the tooth to other Ctenacanthiform teeth, including cusplets section of the teeth (between the medial cusp and lateral cusp). The number of preserved cusplets on the tooth don't seem to match Gilkmanius (which usually doesn't appear to have cusplets between the medial and lateral cusps) or the other reported bond formation ctenacanthiform Heslerodus. The closet match was Saivodus striatus, but I'm not 100% positive on the ID. Below are some comparison images with a Saivodus striatus tooth. https://www.uky.edu/KGS/fossils/fossil-of-the-month_2022-07_Saivodus.php The first image here shows where I think the lateral cusps are (highlighted with green circles) on the specimen (not dissecting scope images). The second image shows where I believe the medial and lateral cusps would have been located (highlighted with green circles) with the right side being where the medial cusp was and the left side where the left lateral cusp was. Here are the same comparison images but with the dissecting scope. I'm sorry if some of the images are really blurry (still trying to fix my phone's camera). But what do you guys think? Do you guys know for the specimen what would be a good ID for it?

When I found this, my initial thoughts were crinoidal. But as can be seen from this gray green section of the Bond Formation, crinoids have the characteristic look that I am used to. Normal Crinoid: : My unknown is black and the "arms" are bumpy:

Here is a brachiopod that I am completely lacking a guess on its identity. The specimen is from the Bond Formation, LaSalle Limestone, Pennsylvanian, found in LaSalle County, Illinois. It is tiny for the formation's other brachiopods.