the beaded crinoid has a cup shaped body, usually hidden from sight, from which about twenty arms project. only a few of these are usually visible at one time and each can be curled up in a coil. short pinnules extend from either side of the arms like vanes on a feather. both the arms and the pinnules are formed from a large number of jointed plates which gives them great overall flexibility. there is an ambulacral groove along the oral surface of each pinnule which is continuous with grooves on the arms. these are linked to grooves leading to the mouth forming feeding channels. the grooves have flap-like lappets overhanging them. at each plate junction on the pinnules there are three tube feet of different length used in food capture and manipulation. the arms can be long and are the only part of the crinoid normally visible as its body is generally concealed in a crevice or inside a sponge. at the base of the crinoid are several cirri, unbranched appendages with which it grips the rock or other substrate. the arms are orange or red and the pinnules are grey or banded in black and white and have a beaded appearance.