Crinoids, or sea lilies, are still around today. They resemble plants at a glance, but are relatives of star fish and sea urchins. These examples, Saccocoma pectinata, are free-floating crinoids, meaning they didn't attach themselves to the substrate with a long stem, like most of their kind, but drifted in the current, their hair blowing in the wind, free as a bird. It was found in the famous Solnhofen Limestone of Bavaria, home of the Archaeopteryx.
Slab varies in size, specimen ~3cm across.