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I had the opportunity to visit another Silurian site in the northern Georgia/southern Tennessee area. This is now the third such site I've visited, but the first in the Rockwood Formation as opposed to the Red Mountain Formation. As far as I can tell there's very little different between the two lithologically and paleontologically, with the Rockwood and Red Mountain occupying pretty much the same stratigraphic position. The difference seems to be that the TGS prefers to use the term "Rockwood" to describe it's Niagaran Silurian system and the GGS and AGS prefer the term "Red Mountain", mostly because the unit is more differentiable in Tennessee whereas in southern NW Georgia and Alabama it is less differentiable. However, the GGS does use the term Rockwood in some of it's reports, and there are some lithological differences between the more southerly and easterly exposures and the more northerly and westerly ones (most notably in the thickness of the hematite beds), so I'm going with Rockwood Formation for these specimens. I had some difficulty in telling the age of the rocks at first. The geologic map I was using wasn't very accurate, and had both the Rockwood Formation and some upper Ordovician units within close proximity to each other. As you'll see with some of the fossils, there are some forms more associated with the Ordovician, such as Isotelus and Vinlandostrophia (Platystrophia), but at the same time I couldn't help but notice there were some similar characteristics between this fauna and the Rose Hill Formation, such as the calymenid molt fragments, and prevalence of Leptaena, which I did not find in the nearby upper Ordovician rocks (not to say it doesn't occur in the Ordovician, just that I didn't find it). Combined with the presence of Eospirifer and the thin beds of iron-rich sandstone and ferruginous limestone, this site is most likely in the Silurian Rockwood Formation. However, in my opinion, it appears to host an earlier, transitionary fauna than the Rose Hill. The collecting itself was pretty easy. The weather was nice, the site not too hard to explore, and the fossils easily extracted from the rock. Most of the exposure was unfossiliferous, however every now and then I'd come across a little part where there'd be a densely packed assemblage, with some loose specimens scattered about. The shale and thin limestone were the most fossiliferous. The first up are some of the brachiopods. A couple of different species it looks like, both tentatively of the genus Dalmanella sp. The report I'm basing this on is pretty old so that name probably no longer applies, however. These are pretty good examples of the more Ordovician forms present at this site. Although Vinlandostrophia (Platystrophia) sp. does occur in the Silurian as late as the Waldron Shale, it is definitely more common in the Ordovician, where V. ponderosa forms veritable coquinas in the upper Leipers Formation. It's a bit hard to see in the bottom one, but it does have a sulcus, unlike most of the Dalmanella sp. present. A few Leptaena sp. Although it is known from the upper Ordovician, I have not found it in the Ordovician rocks nearby and have found several in the Silurian Rose Hill Formation. It is interesting to note that there are such similarities between the two early Silurian fauna across such distances. One characteristic I quickly noticed was that a lot of the specimens in this area occur as loose shells, whereas in Maryland and Pennsylvania they're often internal molds wedged in rock. It makes for easier collecting, and more photogenic fossils! I'm going to go out on a limb and say this is Dalmanella elegantula(?) Pretty good preservation on this one, but I'm not quite sure about it's ID. Maybe some kind of Chonetes (?) sp. Eospirifer sp. with crystalline preservation.

I collected this a couple years back, from the Topeka Limestone in Elk Co. Kansas, and it was identified as Archimedes. Is that correct? it doesn't look quite right to me (in fact, I think it looks more like Penniretepora, but I could be wrong). The specimen is 18 mm long. I apologize for using the penny for scale, the picture was taken before I started using a ruler as the scale in my fossil pictures, and my camera is having problems right now.

My son brought me a rock from Pulaski, TN, and I am trying to study it and identify the various elements in it. From what I can tell (and from what I have learned here in the past) I believe it is mostly made up of encrusted bryozoans, although there is something different about them. There are tiny filament like "sticks" that I have not seen before. Is that perhaps just a type of bryozoan that I am unfamiliar with (quite possible!). There are also a number of embedded items in the rock. The third photo here shows two of them, side by side. I remember from previous answers that I have gotten here that sometimes you see items like this that have "silicalized" (did I get the right word) inside of a rock? Input appreciated! Ramona This is another item that is embedded in the rock and it is surrounded by softer dirt, so I have dug out around it some. I am afraid to dig much more, as I don't want to damage it. Third photo is yet another, similar, embedded item - they all seem to be the same type of thing. Thanks! Ramona

This is another fossil that has me stumped. I think that there is a possibility of bryozoan, because of the pits, but I remain unconvinced. It is from the Leighton Formation, which is Pridoli. The pictures below are of the fossil under raking lighting, to show the pits, then of it under lighting from directly above, and finally with scale (mm). Thanks everyone!

A few weeks back, I happened to accidentally find a fossil while out trail running - my first ever! I found this forum to get help identifying what it was, and figured that would be the end of it. But it turns out that the trail I have been running on for 20 years has lots of fossils, and now I can't stop seeing them! I have been reading this forum and following up with other resources to try to educate myself a little. My mother-in-law was super interested when I showed her a couple that I had picked up, so we decided to go back out there for our very first newbie fossil hunt. My MIL, in her late 70's, hiked up to the top of the mountain with me like it was nothing, and we had a great time poking around. The area we found these in is Devonian, Foreknobs formation. Here are a few of our finds - lots of brachiopods, more crinoids than you can shake a stick at, and some bryozoans! And it sounds like my MIL can't wait to go back - I think this will be a fun activity for the two of us.

Hello guys! These are the specimen from Ile Bizard. This seems to be some kind of Bryzoan, forming a shell structure. #1 1.1 1.2 1.3 1.4 1.5

Hello, friends! This bryozoan is tiny, about a mm wide. It seems to be made up of overlapping tubes arranges diagonally across the zooarium. It come from the Southgate Hill road cutting, St. Leon, Indiana and I think is from the Liberty Formation, Cincinnatian, Late Ordovician due to other species found in the same piece of rock. The other species include Xenocrinus baeri, Hebertella occidentalis, Zygospira modesta, Graptodictya perelegans, Bythopora deliculata, Batostoma sp. and Stictopora emacerata. I think. Thank you for looking.