These are crinoid fossils. Crinoids are echinoderms, related to sea stars and sea urchins. Looking at them, they look somewhat like plants, with a holdfast, which looks root-like, a long, thin body that looks like a stem, and a cup shaped head or calyx, with lots of petal-like tentacles. In the photo are the flat disks that make up the stem-like body.

These fossils came from the top of a cliff, near Lobelville, Tennessee. If you look in the background, you can see other crinoids, as well as coral fossils.