1. The largest collection of ammonite fossils in Japan
The Mikasa City Museum is famous as “The Museum of ammonites” throughout Japan for its outstanding ammonite collection, with displays of more than 600 ammonite specimens of 120+ species, found from Cretaceous marine deposits in Hokkaido. The highlight of the exhibits is the numerous gigantic ammonites. At the entrance to the exhibition room, you will be amazed at a huge 1.3m diameter ammonite, one of the largest ammonites occurred in Japan. In this room, you can touch the displayed ammonites and imagine the ancient ocean in Cretaceous!!
Main exhibition room of natural history “Fossils and Cretaceous world”.
Ammonites are now extinct, and there are no living animals in the world.
However, if you observe the fossilized ammonites carefully, you will understand that it is a relative of the modern squid, cuttlefish, octopus, and nautilus. Here you will learn about the life of ammonites, the history of their discovery, and how to distinguish ammonites.
Until now, many species of ammonites are found, and about 120 species are displayed in the Mikasa City Museum. Ammonite morphology varies such as large conchs, small conchs, conchs with spines or nodes, and conchs with smooth surfaces. Some ammonites have unusually coiled conchs, the so-called “heteromorph ammonites”. Numerous heteromorph ammonites are occurred from Hokkaido. The fossil in the below figure has a unique shape, and it is the most famous heteromorph ammonite in Japan, Nipponites mirabilis. This species was found from Hokkaido in 1904, and the scientific name, Nipponites mirabilis means “wonderful stone in Japan”. This ammonite is well known through all over the world. Many collectors want to get Nipponites mirabilis. The Mikasa City Museum has an outstanding collection of heteromorph ammonites including Nipponites mirabilis.
Most famous heteromorph ammonite, Nipponites mirabilis.
Most specimens displayed in the museum were found from strata of the Cretaceous period (about 100 million years ago) in various regions of Hokkaido, and a part of that was donated to the museum by ammonite collectors around Mikasa City.
2. Fossils of an extinct large marine reptile “Yezo-Mikasa-Ryu” and other creatures of the Cretaceous
The mosasaurid skull, discovered in Mikasa in 1976, is well known as “Yezo-Mikasa-ryu”, and designated as a natural monument of Japan. The discovery of “Yezo-Mikasa-ryu” motivates to establish of the museum, and here visitors can see real fossils of “Yezo-Mikasa-ryu”.Not only that, other related fossils, such as dinosauria, mosasaurids, elasmosaurids, bivalves, gastropods (snail), echinoids (sea wrchin), crinoids (sea lily), fish bones, and shark teeth are displayed in the museum.
Fossils of an extinct large marine reptile “Yezo-Mikasa-ryu”
