Denoting a non-mobile organism. Related Articles: Monster nautiluses of the PalaeozoicAmmonite warsI, a Geologist (Part 2): The geology of Charles DarwinFurther rummages through the cephalopods — ammonites (and others) from around the world (Part 2)Can the end-Permian mass extinction be attributed to a single, catastrophic event?« Back to Glossary Index