Search results
Results from the WOW.Com Content Network
Shell of Pleuroceras spinatum can reach a diameter of about 45–54 millimetres (1.8–2.1 in).These ammonites have a planulate shell with a quadrate whorl section, bearing strong radial ribs ending in ventro-lateral tubercles. The venter is tabulate with a strong serrated keel.
Ammolite comes from the fossil shells of the Upper Cretaceous disk-shaped ammonites Placenticeras meeki and Placenticeras intercalare, and (to a lesser degree) the cylindrical baculite, Baculites compressus. Ammonites were cephalopods, that thrived in tropical seas until becoming extinct along with the dinosaurs at the end of the Mesozoic era.
Ammonites. Smithsonian Institution Press. ISBN 978-1-58834-024-5. Walker, Cyril and Ward, David. Fossils. Dorling, Kindersley Limited, London, 2002. A Broad Brush History of the Cephalopoda by Dr. Neale Monks, from The Cephalopod Page. Ammonite maturity, pathology and old age By Dr. Neale Monks, from The Cephalopod Page. Essay about the life ...
Dactylioceras was a widespread genus of ammonites from the Lower Jurassic period, [1] approximately 180 million years ago . [2] and Like many other ammonites, the genus Dactylioceras is extremely important in biostratigraphy, being a key index fossil for identifying their region of the Jurassic. It had a nearly cosmopolitan distribution during ...
The line where each septum meets the outer shell is called the suture or suture line. Like other true ammonites, Baculites have intricate suture patterns on their shells that can be used to identify different species. A fossil cast of the shell of a Baculites grandis on display at the North American Museum of Ancient Life in Lehi, Utah.
Douvilleiceras is a genus of ammonites from the Middle to Late Cretaceous. Its fossils have been found worldwide, in Africa , Asia , Europe , and North and South America . Description
Perisphinctes is an extinct genus of ammonite cephalopod. They lived during the Middle to Late Jurassic epochs and serve as an index fossil for that time period. [5] The species P. boweni was named after the English chemist and geologist E. J. Bowen (1898–1980). [6]
A rare heteromorph ammonite fossil from the south of France. The species is Crioceratites nolani and the spines have been partially restored to show how it might have appeared in life. Crioceratites is an ammonite genus from the Early Cretaceous belonging to the Ancyloceratoidea.