The arms grow out of a cup-shaped structure in the center of the feather stars, called the calyx. They are serve not, in contrast to those of the sea and brittle stars, the movement of the feather stars but only for food and protection of the calyx (mouth / anus). hey consist of many small plates of bone (similar to the human auditory ossicles) from calcium carbonate and are mutually connected is comparable to a bicycle chain along the entire length of the arms ranges are from tiny finger like structures, called leaflets, which give the animal a feathery appearance. Each leaflet is divided and has a groove in the middle, passing to a groove in the middle of the arm. These grooves or channels are lined by mucus.
The cup contains the digestive organs and is supported by a soft membrane, known as tegmen, separately. It looks roughly like a cone, with a "drum skin" covers the cup. Unlike starfish and brittle stars, feather stars have addressed the opening of the mouth upward. The mouth may be in the middle of the cup but also placed more laterally. The anus is also on top, in some species at the top of a cone or Anal tube.
Feather stars feed on tiny drifting organisms, particles usually of planktonic origin. They collect these passively from the water by their arms per flat to flow like a propeller fan or a comparable satellite dish. The mucus-covered arms or legs collect the food and pass it along the groove to groove in the middle of the arm and then finally to the open mouth. Sitting on the bottom are little moving feets, called cirrus clouds. They are used to cling on sponges or corals.