There are up to 200 slender, translucent, white or pale pink tentacles up to one and a half centimetres long arranged in five rings.

[1][2] This species is found in both shallow and deep water around the western coast of Scotland from the Firth of Clyde northward, particularly in sea lochs.

It is also found round the coasts of the Skagerrak and northern Kattegat and in one location in Connemara, Galway, Ireland.

It seems to prefer vertical rock faces in sheltered sites with little movement of water and has been found as deep as five hundred metres.

It shows an unusual behaviour when occasionally it loses muscle tone and hangs limply from its pedal disc attachment.