Crinoid Four Species Slab. Ulrichicrinus coryphaeus, Actinocrinites gibsoni Dorycrinus gouldi, taxorzrinus collette. Crinoids are sea creatures that live in shallow waters, as well as, in the deepest waters. Their name means "A Lilly Form". Crinoids had a huge adaptive radiation during the Ordovician then again during the Triassic. But, they did nearly go extinct during the Permian extinction event. These Crinoids are from the Mississippian (Carboniferous) roughly 360 to 325 million years ago. Cast Length: 32 cm.