Specimen U (IMAGE) Geological Society of America Caption "Specimen U" illustrates a fossil bed showing shonisaur vertebral disks arranged in curious linear patterns with almost geometric regularity. The arranged vertebrae resemble the pattern of sucker discs on a cephalopod tentacle, with each vertebra strongly resembling a coleoid sucker. Credit Used with permission of Mark McMenamin. Usage Restrictions Educational or non-commercial use only. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.