Era
1831-1899
6
1840-1897
5
1799-1847
3
19th century
3
Cretaceous
3
Eocene
3
From 230 to 570 million years ago
3
Paleozoic
3
1835-1919
2
From 40 to 55 million years ago
2
From 425 to 500 million years ago
2
Ordovician
2
Precambrian
2
Proterozoic
2
1627-1705
1
1638?-1712
1
1666-1727
1
1667?-1719
1
1860-1890
1
1869-1945
1
18th century
1
1900-1999
1
1950-
1
20th century
1
Cambrian
1
Cenozoic
1
Devonian
1
From 140 to 190 million years ago
1
From 345 to 425 million years ago
1
From 65 million years ago
1
From 65 to 140 million years ago
1
From 65 to 230 million years ago
1
Jurassic
1
Mesozoic
1
Silurian
1
d. 1748
1