Clark 1947. A monograph of the existing crinoids. I. The Comatulids. Part 4b-Superfamily Mariametrida (concluded-the family Colobometridae) and Superfamily Tropiometrida (except the families Thalassometridae and Charitomotridae). Bulletin United States National Museum, 83(I 4b) 1947: pp. vii + 478