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On our recent half day trip to the St. Clair fern pits (Aug 11), we focused mostly on finding fossil fern seeds. All of these seed fossils came from one half-day visit. The isolated fossils were found on pieces of shale we inspected from the many piles strewn around the excavated collecting pits. Those that show both halves came from fragmenting small to medium sized pieces from the cast-off pieces around the pits. This was a time-consuming exercise in patience and involved a certain amount of luck but as you can see, we accomplished our goal which was to collect some well-articulated seed fossils. Most of these are Alethopteris seeds including the best find (1a/1b) that shows both halves of the seed and the seed stem. We're wondering about the "split top" seeds - are these Alethopteris seeds starting to open up, or something else? At least two of these (Seeds 4 and 5) are shapes we can't find in the fossil reference literature. 1a and 1b. Alethopteris seed attached by stem. Our best find was this trigonocarpus (fern seed) showing the stem attached to an Alethopteris sprig. We haven't seen too many seed fossils this well defined including the seed stem and associated fern leaves all attached to the same stem. Update: "Trigonocarpus" is the general name given to fern seeds. Our seed is attached by a short stem to the mid-rib of an Alethopteris fern pinnule. We do not believe this is a coincidence (for example the seed lying on top of a leaf) because it is perpendicular to the frond stem and the attachment is pretty clear on both halves of the fossil. We were fortunate to collect both halves and this specimen is very well articulated. (Nancy actually discovered this by splitting open a fragment that was cast aside at one of the small pits dug by other fossil hunters - we have found a lot of our most exciting and rare fossils by segmenting pieces that are already lying on the ground around this site - of course, there are thousands of fragments so it takes a keen eye, it helps to know how the different structures relate to each other so if there is a cluster of a certain species you know what to look for and where, and always it helps to have some luck. We have emailed our photos to the paleontologists at UC-Berkeley who have an artist's rendition of this seed/attachment on their site (see my post below). They mention on their site that not many attached alethopteris seeds have been found. More photos of this are included in my post below. Unidentified Seed 1a and 1b. This is an isolated fern seed not associated with a specific type of fern leaf. Both halves are shown. It has a distinctive groove in the top. Seed 2. Another isolated fern seed. Seed 3. Another similar fern seed. Seed 4 is a different shape - a round seed with serrated edge. Seed 5 is another different shape that we see frequently although it's usually not very well articulated. Is this a seed or something else? It's always this shape. Seed 6a and 6b are both halves of the same seed and have the same shape (groove at the top) as Seed 1a/1b above. Seed 7 is another isolated seed. Thanks in advance for your opinions!

Trigonocarpus (Seed) from St. Clair PA This is a walnut shaped fossil discovered Aug. 30 at the St. Clair, PA Carboniferous fern site. This was found by Nan while she was looking for insects/traces - assume it is a fern seed (trigonocarpus is the morphologic genus given to fern seeds) but we haven't seen this one before. It is about 3 1/2 centimeters long: Here are some closeups:

These fossils are from our second visit to St. Clair (Aug 4) - several are fossils we haven't seen before so we appreciate help with IDs. Special thanks to Fossildude19 for the excellent starting points. Note: some of the images are out of order when you look at the photos below, because I am renaming and reposting them as they are being identified: 1 - Pecopteris Squamosa - This is small and the leaves are very close together and parallel - based on Lesquereux - amazing that some of the best fern identification sources are from 1879! 2 - Calamites Stem Fragment - A thin Calamites branch. 3 - Unidentified Plant - Nancy calls this a "flower" - of course it isn't, but it seems to be a different shape from others we collected at St. Clair. 4 - Alethopteris and Annularia - Included this because it makes for a nice artistic layout. 5a-5b - Asterophyllites equisetiformis - This interesting pattern appears over a large area several meters square in one part of the St. Clair site, and covers the surface of a very large flat boulder in one area of the site. (source: 6 - Siggilaria - This is our second Siggilaria trunk impression. Some of the trunk and branch fossils (Calamites, Siggilaria) are very exotic and interesting to collect. 7a-7c - Trigonocarpus (Seeds of the Alethopteris Fern) - The same shape appears in three different samples collected on our two trips and according to our friends on the site and reference materials, they appear to be Trigonocarpus seeds, which is very exciting because we keep reading about seed ferns but these are our first fossil seeds. One reference describes Trigonocarpus as the seeds of Alethopteris (which is the most common fern found at St. Clair) - other sources give these the nickname "fossil pecans" because of their physical resemblance. 8a-8b and 9a - Cyclopteris - Fan Shaped Leaves - Some of the reference books show round fan shaped versions of some common ferns but this looks like something separate so we're going with Cyclopteris. We'll try to find a separate, more articulated sample on a future trip. 10 - Unidentified Fern. 11 - Assume this is Sphenopteris. 12 - Assume this is Neuropteris - Where Neuropteris sometimes has rounded leaves (??) 13 - Sphenophyllum - Including just for fun. I'll update the names in this list as the IDs are confirmed. One of our goals continues to be, finding scarce specimens we haven't come across yet, as well as articulated fossils, designs and larger pieces for display. As you can see, we're already making great headway identifying these. Thanks to everyone who helped us ID our finds in the past 2 months, and especially for helping with these...we're really surprised how many different species there are at this single site, all very close together.