Last week we took a ride to Lake Michigan to do a short search before the weather turned bad. The previous day had strong winds with large waves and I thought we might find some interesting things. We found plenty of Favosites, Halysites, and Rugose corrals as well as some of the other usual finds. The one unusual find was what I believe to be an internal mold of a Pentamerus oblongus brachiopod. I don't find many brachiopods and as such I'm not 100% sure on my ID. Please confirm or correct. Tha