Mud Bisters Caused by Polydora websteri (IMAGE) Royal Netherlands Institute for Sea Research Caption Mud blisters caused by Polydora websteri. Credit Dagmar Lackschewitz Usage Restrictions None 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.