Ordovician algae

[Rockwood]

These were found in a boulder used as rip rap along a rail bed here in Maine. I've never seen rock like it exposed in cuts along the route, so it may have been transported some distance.

These are old photos, but I've donated the best examples to a local museum (Bates Museum, Hinkley, Maine) and the label on it was destroyed. Unfortunately I can't find the post, but I'm quite sure it was identified as a calcareous algae known from the Ordovician.

Can anyone help me identify it so that I can inform the folks at the museum. It's a small museum and they don't really have a paleontologist.

[TqB]

Same as this post? We came up with Prismostylus (formerly Tetradium).

http://www.thefossilforum.com/index.php?/topic/54804-one-more-try/

These transverse section bits are particularly recognizable (bottom right, first photo):

Edited December 3, 2022 by TqB