Cerata are barely as long as half the width of the body. They are attached along either side of the body, but look as if the whole back, apart from the hump over the pericardium, is occupied by them. They are so packed together that it is not possible to discern an arrangement of groups or lines (Sars, 1829).
Southern Norway, November 2003. © CC BY-NC-ND, A. Hansen www.flickr.com/photos/xoto/