This is a cool plate of Mississipian aged echinoderm fossils
from Missouri. There is a detailed calyx of a Abatocrinus grandis crinoid and the rock is full of crinoid stem fragments.
Crinoids, sometimes commonly referred to as sea lilies, are animals, not plants. They are echinoderms related to starfish, sea urchins, and brittle stars. Many crinoid traits are like other members of their phylum; such traits include tube feet, radial symmetry, a water vascular system, and appendages in multiples of five (pentameral). They first appeared in the Ordovician (488 million years ago) and some species are still alive today.