A fossilized shell.

Lituites

A fossilized shell.

An illustration of a lobster fossil.

Lobster Fossil

An illustration of a lobster fossil.

An illustration of a maclurites, an extinct genus of snails.

Maclurites

An illustration of a maclurites, an extinct genus of snails.

An illustration of the operculum of the maclurites, an extinct genus of snails.

Operculum of Maclurites

An illustration of the operculum of the maclurites, an extinct genus of snails.

The fossilized skeleton of a Megatherium.

Fossil Megatherium

The fossilized skeleton of a Megatherium.

"Skeleton of Mesohippus bairdi, the three-toed ancestor of our horse. This animal was about the size of a sheep." — Davison, 1906

Skeleton of a mesohippus bairdi

"Skeleton of Mesohippus bairdi, the three-toed ancestor of our horse. This animal was about the size…

An ancient mollusk from the Paleozoic time, Goniatites Marcellensis from the Hamilton group.

Goniatites Mollusk Fossil

An ancient mollusk from the Paleozoic time, Goniatites Marcellensis from the Hamilton group.

An ancient mollusk from the Carboniferous Age, the Archimedes reversa.

Archimedes Mollusk

An ancient mollusk from the Carboniferous Age, the Archimedes reversa.

An ancient mollusk from the Paleozoic time, Goniatites Marcellensis from the Hamilton group.

Goniatites Mollusk

An ancient mollusk from the Paleozoic time, Goniatites Marcellensis from the Hamilton group.

Shell of a Nummulite cut transversely and in part horizontally.

Shell of a Nummulite

Shell of a Nummulite cut transversely and in part horizontally.

A mollusk radiate from the Paleozoic time, Orthis occidentalis.

Orthis Mollusk

A mollusk radiate from the Paleozoic time, Orthis occidentalis.

A mollusk radiate from the Paleozoic time, Orthis varica of the Niagara group.

Orthis Mollusk

A mollusk radiate from the Paleozoic time, Orthis varica of the Niagara group.

A mollusk radiate from the Paleozoic time, Pterinea emacerata from the Niagara group.

Pterinea Mollusk

A mollusk radiate from the Paleozoic time, Pterinea emacerata from the Niagara group.

A remarkable genus of fossil lizards, peculiar to the Mesozoic strata. Its anomalous structure was long a puzzle to comparative anatomists.

Pterodactyl

A remarkable genus of fossil lizards, peculiar to the Mesozoic strata. Its anomalous structure was long…

A remarkable genus of fossil lizards, peculiar to the Mesozoic strata. Its anomalous structure was long a puzzle to comparative anatomists.

Pterodactyl

A remarkable genus of fossil lizards, peculiar to the Mesozoic strata. Its anomalous structure was long…

"So peculiar and strange is the structure of these animals, that the first specimen discovered was classed by one naturalist as a bird, by another as a species of bat, and by yet a third as a flying reptile." — Goodrich, 1844

Pterodactyle skeleton

"So peculiar and strange is the structure of these animals, that the first specimen discovered was classed…

An ancient radiate from the Carboniferous Age, the Actinocrinus proboscidialis.

Actinocrinus Radiate

An ancient radiate from the Carboniferous Age, the Actinocrinus proboscidialis.

A radiate from the Paleozoic time, Caryocrinus ornatus.

Caryocrinus Radiate

A radiate from the Paleozoic time, Caryocrinus ornatus.

A radiate from the Paleozoic time, Chaetetes lycoperdon.

Chaetetes Radiate

A radiate from the Paleozoic time, Chaetetes lycoperdon.

A radiate from the Paleozoic time, Lecanocrinus elegans.

Lecanocrinus Radiate

A radiate from the Paleozoic time, Lecanocrinus elegans.

An ancient radiate from the Carboniferous Age, the Lithostrotion Canadense.

Lithostrotion Radiate

An ancient radiate from the Carboniferous Age, the Lithostrotion Canadense.

A mollusk radiate from the Paleozoic time, Stictopora acuta.

Mollusk Radiate

A mollusk radiate from the Paleozoic time, Stictopora acuta.

A mollusk radiate from the Paleozoic time, Orthoceras junceum.

Mollusk Radiate

A mollusk radiate from the Paleozoic time, Orthoceras junceum.

An ancient radiate from the Carboniferous Age, the Pentremites pyriformis.

Pentremites Radiate

An ancient radiate from the Carboniferous Age, the Pentremites pyriformis.

A radiate from the Paleozoic time, Petraia corniculum.

Petraia Radiate

A radiate from the Paleozoic time, Petraia corniculum.

A radiate from the Paleozoic time, Zaphrentis bilateralis of the Clinton group

Zaphrentis Radiate

A radiate from the Paleozoic time, Zaphrentis bilateralis of the Clinton group

An ancient radiate from the Carboniferous Age, the Zeacrinus elegans.

Zeacrinus Radiate

An ancient radiate from the Carboniferous Age, the Zeacrinus elegans.

A mollusk radiate from the Paleozoic time, Raphistoma lenticularis.

Raphistoma Mollusk

A mollusk radiate from the Paleozoic time, Raphistoma lenticularis.

An illustration of a sea fern fossil from the carboniferous period. The Carboniferous is a geologic period and system that extends from the end of the Devonian period, about 359.2 ± 2.5 Ma (million years ago), to the beginning of the Permian period, about 299.0 ± 0.8 Ma.

Sea Fern Fossil

An illustration of a sea fern fossil from the carboniferous period. The Carboniferous is a geologic…

An illustration of a sea-lily fossil.

Sea-lily

An illustration of a sea-lily fossil.

An illustration of a Club-shell fossil from the Tertiary period. The Tertiary is a an out-of-date term for a geologic period 65 million to 1.8 million years ago. The Tertiary covered the time span between the superseded Secondary period and an out-of-date definition of the Quaternary period. The period began with the demise of the non-avian dinosaurs in the Cretaceous–Tertiary extinction event, at start of the Cenozoic era, spanning to beginning of the most recent Ice Age, at the end of the Pliocene epoch.

Shell Fossil

An illustration of a Club-shell fossil from the Tertiary period. The Tertiary is a an out-of-date term…

The cone shells are numerous and beautiful found in southern and tropical seas.

Cone Shell

The cone shells are numerous and beautiful found in southern and tropical seas.

An ancient mollusk from the Carboniferous Age, the Spirifer cameratus.

Spirifer Mollusk

An ancient mollusk from the Carboniferous Age, the Spirifer cameratus.

An illustration of a sponge fossil.

Sponge Fossil

An illustration of a sponge fossil.

A mollusk radiate from the Paleozoic time, Strophomena rhomboidalis

Strophomena Mollusk

A mollusk radiate from the Paleozoic time, Strophomena rhomboidalis

A fossilized shell.

Turrillites

A fossilized shell.