Metacrinus rotundus is a marine animal with a fan-like crown of arms supported by a tether-like stalk. It uses the arms, which are covered in rows of feather-like appendages (pinnules), to trap food such as plankton.
Nakano, H, Hibino, T, Hara, Y, Oji, T and Amemiya, S (2004) Regrowth of the stalk of the sea lily, Metacrinus rotundus (Echinodermata: Crinoidea). Journal of Experimental Zoology, 301A: 464-471.
Oji, T (1986) Skeletal variation related to arm regeneration in Metacrinus and Saracrinus, recent stalked crinoids. Lethaia, 19: 355-360.
Oji, T (1989) Growth rate of stalk of Metacrinus rotundus (Echinodermata: Crinoidea) and its functional significance. Journal of the Faculty of Science, University of Tokyo22: 39-51.
Oji, T and Amemiya, S (1998) Survival of crinoid stalk fragments and its taphonomic implications. Paleontological Research2(1): 67-70.
Oji, T and Okamoto, T (1994) Arm autonomy and arm branching pattern as anti-predatory adaptations in stalked and stalkless crinoids. Paleobiology20(1): 27-39.