Search results
Results from the WOW.Com Content Network
The resulting spontaneous concentric precipitation of minerals around a fossil, a concretion, is responsible for the outstanding preservation of many ammonite fossils. When ammonites are found in clays , their original mother-of-pearl coating is often preserved.
This list of ammonites is a comprehensive listing of genera that are included in the subclass †Ammonoidea, excluding purely vernacular terms. The list includes genera that are commonly accepted as valid, as well as those that may be invalid or doubtful ( nomina dubia ), or were not formally published ( nomina nuda ), as well as junior ...
This ammonite has a ceratitic suture pattern on its shell (smooth lobes and frilly saddles). Evolution of the frilly saddles is thought to be due to increased pressure on the shell, at greater depth. The frilly pattern would increase the strength of the shell and allow Ceratites to dive deeper, possibly in search of food. [citation needed]
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
Ceratitidae is an extinct family of ammonite cephalopods. Fossils of Ceratitidae are found in the Triassic marine strata throughout the world, including Asia, Europe, the Middle East, North America, and Oceania.
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]
Download as PDF; Printable version; In other projects ... Manticoceras is a genus of ammonites included in the family ... Fossils of species within this genus have ...
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.