Cylindracanthus rectus rostral bone from the Eocene Bracklesham Beds of Bracklesham Bay, Sussex. Cylindracanthus is an extinct genus of Ziphoid fish (swordfish). The rostrum is the long, sword-like projection characteristic of swordfish. Vary rarely are fossils of the rostrum complete, they are usually found as fragments. These fragments measure between 3 - 5 cm in length and are supplied in small plastic bags with an information label. The Bracklesham beds in which these bones were found are well known among paleontologists and fossil collectors in Britain; they have yielded over 160 different species of fish and the beds continue to be productive today despite having been pillaged by collectors for over 100 years.