Appearance
The variable bushy feather star often keeps its body concealed in a crevice and the only visible part is its array of arms, especially when it is young. There are in fact five rays attached to the upper part of the body but these subdivide into a number of arms and when one of these is lost, two grow in its place. The arms are flexible, being formed from many jointed calcareous small plates known as ossicles, and can be coiled up. On either side of each arm are short side branches known as pinnules. On the underside of the body are about twenty clawlike appendages known as cirri which are used to cling on to the underlying surface, but they are lost in older specimens, which attach directly using the underarms.