The crinoids spread their arms out at right angles to the direction of the water current and trap tiny planktonic animals on small tube feet that cover their arms, then they transport the prey to their mouths with hair-like cilia. Large numbers of clam-like creatures called brachiopods litter the sea floor. Swimming sluggishly above the ocean bottom, ancient relatives of the octopus, nautiloids and ammonoids, feed on invertebrates. Fierce-looking armored predatory fish swim above the cephalopods, also looking for food. The limestone of the sea floor is made up of the remains of the ancient corals.
Coral is created by the action of sedentary species of cnidarians.
Horn corals, some of which are almost four feet long, as well as honeycomb coral and pipe organ coral, trap plankton from the passing currents of water. Before your journey to the Devonian fossil beds, make sure to visit the Falls of the Ohio State Park interpretive center. There is also a fascinating series of displays on the history of the fossil creatures here that will further spark your imagination and interest. Now extinct, trilobites once inhabited every sea on the planet.