Mosasaurs are an extinct group of large marine reptiles. Their first fossil remains were discovered in a limestone quarry at Maastricht on the Meus...

Mosasaurs are an extinct group of large marine reptiles. Their first fossil remains were discovered in a limestone quarry at Maastricht on the Meus...

Mosasaurs are an extinct group of large marine reptiles. Their first fossil remains were discovered in a limestone quarry at Maastricht on the Meus...

Mosasaurs are an extinct group of large marine reptiles. Their first fossil remains were discovered in a limestone quarry at Maastricht on the Meus...

Mosasaurs are an extinct group of large marine reptiles. Their first fossil remains were discovered in a limestone quarry at Maastricht on the Meus...

Mosasaurs are an extinct group of large marine reptiles. Their first fossil remains were discovered in a limestone quarry at Maastricht on the Meus...

Mosasaurs are an extinct group of large marine reptiles. Their first fossil remains were discovered in a limestone quarry at Maastricht on the Meus...

Mosasaurs are an extinct group of large marine reptiles. Their first fossil remains were discovered in a limestone quarry at Maastricht on the Meus...

Mosasaurs are an extinct group of large marine reptiles. Their first fossil remains were discovered in a limestone quarry at Maastricht on the Meus...

Mosasaurs are an extinct group of large marine reptiles. Their first fossil remains were discovered in a limestone quarry at Maastricht on the Meus...

Mosasaurs are an extinct group of large marine reptiles. Mosasaur teeth come in various sizes and from various species.  This specimen is a large, ...

This specimen is a piece of Mexican Amber, also know as Mexican Mayan Amber. It is harder than most other ambers, which makes it less fragile and i...

Brittle stars, or ophiuroids, are echinoderms in the class Ophiuroidea, closely related to starfish. They crawl across the sea floor using their fl...

Brittle stars, or ophiuroids, are echinoderms in the class Ophiuroidea, closely related to starfish. They crawl across the sea floor using their fl...

Brittle stars, or ophiuroids, are echinoderms in the class Ophiuroidea, closely related to starfish. They crawl across the sea floor using their fl...

Brittle stars, or ophiuroids, are echinoderms in the class Ophiuroidea, closely related to starfish. They crawl across the sea floor using their fl...

Brittle stars, or ophiuroids, are echinoderms in the class Ophiuroidea, closely related to starfish. They crawl across the sea floor using their fl...

Brittle stars, or ophiuroids, are echinoderms in the class Ophiuroidea, closely related to starfish. They crawl across the sea floor using their fl...

Brittle stars, or ophiuroids, are echinoderms in the class Ophiuroidea, closely related to starfish. They crawl across the sea floor using their fl...

Brittle stars, or ophiuroids, are echinoderms in the class Ophiuroidea, closely related to starfish. They crawl across the sea floor using their fl...

Brittle stars, or ophiuroids, are echinoderms in the class Ophiuroidea, closely related to starfish. They crawl across the sea floor using their fl...

Brittle stars, or ophiuroids, are echinoderms in the class Ophiuroidea, closely related to starfish. They crawl across the sea floor using their fl...

Genuine, museum-quality, Ophiuroidea Brittle Star Fossil. Ophiura ophiura or the serpent star is a species of brittle star in the order Ophiurida. ...

Two Orthoceras fossils found in a sea-bed matrix. Orthoceras ("straight horn") had a slender, elongated shell, with the middle of the body chamber...