What is Comulatida

Comulatida (feather stars; class Cri-noidea, subclass Articulata) An order of crinoids which lack a stem or column in the adult slate and which swim freely. The uppermost 'ossicle of the column ismod-ified into a conical or discoidal plate (a centrodorsal). This bears numerous cirri [seeCIRRUS), which are used to grasp sub¬strata. The order has existed since the 'Jurassic.