Catalog Number: CG-0013
Closely related to modern horsetails, Calamites is an extinct genus that existed from the Carboniferous until the early Permian. Horsetails are one of several genera considered to be living fossils. They reproduce using spores, which were similar to Lepidodendron. Both Lepidodendron and Calamites produced cone arrangements of spores. This genus is the only one in this time period to have a clonal habit, much like Bamboo or American Aspens.
I found this particular specimen in shale. It shows the intersection of nodes where the needle-shaped leaves were attached. There is likely more to see under the layers of this piece, however I would risk destroying the impression on the top portion. The shale is fragile and would disintegrate easily.
Another form of Calamites that can be found is the leaf whorls. I have not found any of these locally yet, but seeing that I am able to find the stalks, the whorls are around somewhere.
More Online About Calamites
Article – Wikipeda